How to manage the updated feed option in the Google app
by Jack Wallen in Mobility on August 3, 2017, 10:31 AM PST
Google recently updated an Android feature called the feed. Here's how to enable and configure it in the Google app.
Image: Jack Wallen
If you've been paying attention, you might have noticed that Google added what they call the feed to your search tool last December, and recently updated it. This feed includes news stories, sports scores, and videos, all of which are based on your previous Google searches. This new feature does an outstanding job of presenting to you information of interest (so long as you are actually using Google search).
But how do you manage this new feed? Thankfully, the developers saw to it to give users everything they need to manage their feed. Let's me show you how.
SEE: Google's updated feed taps machine learning to show new topics before you search for them (TechRepublic)
Turning on the feed
Before you start working with the feed, you should make sure it is enabled. By default, the underlying system should be on. On the off-chance yours isn't, here's how to enable it:
Open up the Google app
Swipe right from the left edge
Tap Settings
Tap Accounts & privacy | Google activity controls | Web & App Activity
If disabled, tap the slider to enable (Figure A)
Enabling the Web & App Activity feature.
Now you're ready to work with the feed.
How to get to the feed
This will depend upon the device and the home screen launcher you use. On the OnePlus 3 using the Google Now Launcher, you simply swipe right from the left edge of the screen, to reveal the Google Search app. If that doesn't work for you, you can always open up the App Drawer, locate the Google app, and tap to launch.
How to configure the feed
Once you have the Google app open, swipe right from the left edge of the screen and then tap Settings (Figure B).
Getting to the Google app Settings window.
In the resulting window, locate and tap Your feed. This new screen is where you take care of all of the options provided for the feed (Figure C).
Figure C
The Feed options window.
The first thing you should do is make sure the feed is enabled. If not, tap the slider to enable the feature. Once feed is enabled, scroll down and enable all of the notification options of interest to you (such as Weather, commute time, sports, topics of interest, etc. - Figure D).
Figure D
Enabling notifications for the Feed.
By default, all options are enabled. Chances are there will be an option or two that won't interest you. I recommend disabling those, so that your feed is streamlined. Chances are, if there's a topic that doesn't interest you, you won't be searching for it anyway--so it probably won't appear anyway. Even so, it's best to minimize what feed is looking for in your searches.
You can also enable/disable notifications; however, I've yet to actually see an alert (in my Notification Shade) or hear a notification from the feed, nor does the Ringtone ever seem to chime.
Give it time to grow
The feed is relatively new, so there are bound to be growing pains as Google continues to tweak the feature. Of course, this is Google, so there's no guarantee that the feed will last. For the meantime, however, it's a pretty cool feature that learns what to feed you as you search.
Happy feeding!
5G and Mobile Enterprise Newsletter
5G networks and devices, mobile security, remote support, and the latest about phones, tablets, and apps are some of the topics we'll cover. Delivered Tuesdays and Fridays
New Android spyware can record your voice, take photos with your camera, and steal app data (TechRepublic)
Final Android O developer preview arrives, here's how to prepare your apps (TechRepublic)
How to add more news sources to Google Assistant (TechRepublic)
How to migrate your Android contacts to Google (TechRepublic Video)
What you can expect from Android O (ZDNet)
Comment and share: How to manage the updated feed option in the Google app
By Jack Wallen
Jack Wallen is an award-winning writer for TechRepublic, The New Stack, and Linux New Media. He's covered a variety of topics for over twenty years and is an avid promoter of open source. For more news about Jack Wallen, visit his website jackwallen....
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UPDATE: One dead, two injured in morning crash in Manor, police say
Kelsey Bradshaw @kbrad5
Feb 18, 2019 at 6:22 AM Feb 18, 2019 at 1:31 PM
12:50 p.m. update: One person died and two others were hospitalized on Monday morning after a crash in Manor.
The crash happened around 5:20 a.m. on U.S. 290 at Cedar Street.
Manor police said a sport utility vehicle heading east slammed into the side of an 18-wheeler as it was turning to head west on the Cedar Street turnaround.
The driver of the SUV and two passengers were taken to the Dell Seton Medical Center after the crash.
The front passenger, who was flown to the hospital, later died from their injuries, police said. The driver was still receiving emergency medical care at the facility on Monday afternoon, and the other passenger was being treated for injuries that were not considered life-threatening, police said.
Police did not name anyone involved in the crash on Monday.
6:35 a.m. update: All eastbound lanes of U.S. 290 near FM 973 in Manor have reopened after a truck crash shut down the highway this morning, Texas Department of Transportation officials said.
Earlier: All eastbound lanes of U.S. 290 near FM 973 in Manor are shut down because of a truck crash in the area, Texas Department of Transportation officials said.


Rated: PG-13
Himesh Patel, Lily James, Kate McKinnon and Ed Sheeran.
Director: Danny Boyle. Producers: Danny Boyle, Bernard Bellew, Tim Bevan, Richard Curtis, Alexander Dostal, Eric Fellner and Matthew James Wilkinson. Executive Producers: Nick Angel and Lee Brazier. Screenwriters: Jack Barth and Richard Curtis. Music: Daniel Pemberton. Cinematographer: Christopher Ross.
Hamish Patel may not be a household name yet, but his impressive, big screen debut in the romantic, music comedy, "Yesterday" might make him one.
Prior to "Yesterday" Patel starred on the BBC soap opera "EastEnders."
In "Yesterday," from Academy Award winning director Danny Boyle ("Slumdog Millionaire") and screenwriter Richard Curtis ("Four Weddings & A Funeral"), Patel plays Jack Milak, an aspiring singer/songwriter from England.
Jack often gets frustrated because no one outside of his family and a small circle of friends go to his shows. Still, he hustles and hopes for that big break.
Thankfully his best friend and love interest/manager Ellie Appleton (the delightful Lily James, "Mama Mia! Here We Go Again") thinks the world of Jack and his music. She's the best thing in his life although it takes him a minute to realize it.
The saying that inspiration can strike at any time proves true, but in a crazy way for Jack. One night after a disastrous performance in Sussex, Jack is riding his bike home when there's a 12 second worldwide blackout. He's hit and nearly killed by a bus.
When Jack awakes from his hospital bed, get this, he's the only person who knows about the Beatles and all their music. It's as if the group never existed. Yet Jack knows every single song. Well, here comes the sun.
Jack seizes this miraculous opportunity and claims the Beatles songs as his own compositions. During a get together with Ellie and his friends, Jack, still looking kind of silly with his two front teeth missing, tells them about some songs he wrote.
He launches into "Yesterday" and everyone is floored. Almost everyone. One of his friends tells him it's a very good song, but "it's not Coldplay." What the hell.
Jack's songwriting and singing catch the attention of singer Ed Sheeran. Sheeran is naturally funny. Who knew?
He drops by Jack's house surprising him and his oddball parents, Sheila and Jed (Meera Syal, "The Nutcracker and the Four Realms") and Sanjeev Bhaskar (TV's "The Porters").
Sheeran tells Jack that he's a big fan of his work and even suggests he change the title of "Hey Jude" to "Hey Dude." There's also a funny scene when Sheeran challenges Jack to write a catchy song in 10 minutes. Sheeran comes back with a decent ballad. Jack launches into "The Long and Winding Road." Game over. Sheeran says it's the best song he's ever heard and wonder's how Jack cranks this great music out so easily. Of course, we know, he's getting by with a little help from his friends.
Jack's superstar status comes with a price. His success has pushed Ellie to the side. He's also allowed Sheeran's overzealous manager/agent Debra Hammer (Kate McKinnon, TV's "Saturday Night Live") to take control of his career. For the record, this is McKinnon's best performance yet.
Despite his stardom, Jack is consumed with guilt and wonders just how long he'll be able to keep up the charade. It all comes to a head when he takes the stage to perform.
"Yesterday" is a charming love story that doesn't get too sappy. And I also enjoyed Joel Fry (TV's "Requiem") who is hilarious as Patel's friend Rocky. Most of all, "Yesterday" is a glowing tribute to The Beatles and their enormous body of music.
As for Hamish Patel, he's flat out sensational. He truly carries "Yesterday." It's a delightful and charming summer treat.
Check Out This Trailer For "YESTERDAY"


Home > HISTORY > Stocktake Pack - 10 great books
Stocktake Pack - 10 great books
ISBN:285
Connor Court Stocktake Sale
10 great books for $100, including postage.
A MUST READ COLLECTION OF BOOKS FOR ANYONE ON THE RIGHT SIDE OF POLITICS
Normal Retail Price $220.
THE GREENS: Policies, Reality and Consequences -- Edited by Andrew McIntyre (Paperback, 150 pages)
The idea for this book came from an awareness of the alarming void in media analysis of the Greens' policies at a time when they have been gaining in political strength.
This book brings together leading Australian experts who look at a wide range of their policies in detail – from Agriculture to Z00phytes – to reveal the practical consequences of these policies.
AUSTRALIAN INTELLECTUALS Their strange history & pathological tendencies -- Greg Melleuish (Paperback, 90 pages)
Why are Australian Intellectuals and academics so hostile to contemporary Australian life? Why do they so often hold disparaging views of their fellow Australians? This was not always the case. In the nineteenth century, Australians of an intellectual disposition sought to work with their fellow Australians to build a better and freer country.
Fit for Service: Meeting the demand of the Asian middle class -- Andrew Bragg (Paperback, 88 pages)
Australia's prosperity is built upon free, open markets and creative trade policy. At a time of increasing protectionism, our North Asian trade agreements open the door to increased service exports to the region's rapidly growing middle class. But does Australia have what it takes to capitalise on these deals? Fit For Service examines what Australia must do to succeed in exporting the know-how that is disrupting the 21st century.
Quiet achievers: The New Zealand path to reform -- Oliver Hartwich (Paperback, 90 pages)
In Quiet Achievers, Oliver Hartwich looks at New Zealand's record on spending, tax and welfare. He discovers that while Australia has been avoiding difficult decisions, the New Zealanders have been silently forging ahead.
What Women Want: Fun, Freedom and an End to Feminism -- Ella Whelan (Paperback, 90 pages)
And now, in this brilliant book, she puts the case for female autonomy against feminist victimhood. Some feminists will no doubt cry 'anti-feminist!', but this would be inaccurate; in fact, this book is in the tradition of the Suffragettes, the female explorers, the female workforce and other female pioneers of the 20th and 21st centuries who demanded that society should mine rather than suppress women's potential. All women and men who value women's liberation should read this. -- Brendan O'Neill (from the Foreword).
Why Europe Failed -- Oliver Hartwich (Paperback, 82 pages)
"A compelling essay" -- Hon John Howard OM AC
In this essay, Dr Oliver Hartwich presents a sketch of Europe's decline. The continent that invented and dominated the modern world has gambled away its future. Run by distant and unaccountable political elites, the EU embarked on a project of political integration for which there was never any popular appetite. At the same time, government spending across the continent increased to levels never before seen in history. To make matters worse, Europe's population is ageing and shrinking.
Audit Commissions - reviewing the reviewers -- Kate Jones and Scott Prasser (Paperback, 80 pages)
Audit Commissions: Reviewing the Reviewers is the first comprehensive assessment of all fourteen state, territory and federal audit commissions established since 1988. That audit commissions are a particular Australian institution makes this study of value to both Australian and international audiences. The volume outlines the history, reasons for appointment, roles, processes, members, impact and suggests where audit commissions fit in the overall architecture of Australian government.
Australian Essays by Roger Scruton, With a foreword by Chris Berg (Paperback, 98 pages)
Roger Scruton explores the fallacies of our technocratic age. Roger Scruton is interested in what makes us human: our individual self-conscious, our search for the divine, our yearning for community, and our sense of place. Tackling subjects from religion, to communism, to meat-eating, Roger Scruton rejects the attempts of ideologues to reduce humanity into abstraction.
Lessons from the Global Financial Crisis: The Relevance of Adam Smith on Morality and Free Markets -- Richard M. Morgan (Paperback, 105 pages)
Adam Smith was an advocate of the free market, however his first work, The Theory of Moral Sentiments, was on ethics and was widely acclaimed at the time. Commentators have tended to review this work as separate to his work on political economy. However the global financial crisis has shown the relevance of morality and the free market. Whilst The Wealth of Nations is concerned with political economy, Smith's pointed attacks on exploitation and greed reflect the ethics outlined in his first work.
Lessons from the Global Laboratory of Economic Experimentation -- Dan Mitchell (Paperback, 84 pages)
When seeking to educate and convince a non-ideological audience that they should favor economic freedom, I've learned that there's no substitute for this kind of real-world evidence. Most people think of themselves as being practical. My daily columns are designed to reach these people. If I can reach their minds, maybe their hearts will follow. -- From the Introduction
Captain James Cook: Claiming the Great South Land
Aramaic Catholicism: Maronite History and Identity
Gambling for Love: Australia's First Decimal Currency Bank Robber -- John Killick
THE RED RUGS OF TARSUS -- Helen Davenport Gibbons
A Cohort of Pioneers: Australian postgraduate students and American postgraduates degrees 1949 – 1964
Radicals in Australian Social Work: Stories of Lifelong Activism (COPY)
DON LUIGI STURZO: THE FATHER OF SOCIAL DEMOCRACY -- John Molony
The Billings Enigma -- Tess Livingstone
THE MANNIX ERA: Melbourne Catholic Leadership 1920-1970 -- Patrick Morgan
More Cloak Than Dagger: One Woman's Career in Secret Intelligence -- Molly Sasson
THE LONELY LIBERTARIAN Turning Ideas into Gold – then Gold into Ideas -- RON MANNERS
Lebanese in Australia: A Changing Mosaic -- Trevor Batrouney and Andrew Batrouney
Ocean of Light: 30 Years in Tonga and the Pacific -- Peter Warner
THE IRVINEBANK MASSACRE -- PAUL DILLON
CARDINAL PELL, THE MEDIA PILE-ON & COLLECTIVE GUILT -- Gerard Henderson


Things to Do in Branson Missouri
Branson Guide
Yosemite California Travel Guide
Things To Do and Explore Keystone Colorado
Lake Gaston Travel Guide
National Shrimp Festival In Gulf Shores..
Soar to New Heights and Visit the Blue Ridge Mountains
by Robyn Adams
Branson Missouri
The town of Branson boasts a selection of fun attractions, vibrant entertainment hubs, and picturesque outdoor spots. For sure, you wouldn't miss the experience of spending a vacation in this amazing town. It's an excellent place to create special moments with your friends and loved ones.
Branson comes complete with the glitz and the glamor of the big city but still holds tight to its small town charm. Take a dinner cruises on one of Branson's many showboats or visit the Branson Strip for a little bit of Las Vegas in Missouri. The shores of Lake Taneycomo are home to Branson Landing, a popular spot to watch fountain shows all while enjoying the best shopping and hearty meals the south has to offer. And let's not forget that Branson, Missouri is an entertainment mecca with concerts, shows and theaters almost everywhere!
If you want a fun and exciting getaway that you'll remember in your lifetime, I couldn't recommend more the beautiful town of Branson, Missouri. Here's a list of popular tourist attractions that you should visit in this town.
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Talking Rocks Cavern
This cavern system is a cool getaway during summertime in Branson. Experience an exhilarating underground tour as you walk through walkways and climb the stairs inside the cave formations.
Outside the cave system, there's a hiking trail that leads to a watchtower. You can also hang out with your companions in its picnic area or tee up on its mini-golf course.
Aquarium at the Boardwalk
The Aquarium at the Boardwalk is one of the must-visit places in Branson because of its stunning features that you'll surely love. It houses over 7,200 individual sea creatures, such as golden puffers, stingrays, lionfish, Giant Pacific octopus, sea sharks, and many more.
There are also dozens of coral reefs that serve as home to the schools of fish here. Stroll along the tunnels and be amazed at the fantastic structures like the Jelly Infinity Room, Kelp Forest, Mermaid Palace, and Ocean Kaleidoscope.
Titanic Museum Attraction
Have you ever wondered what it feels like to be inside the famous Titanic? While the original ship is now a wreckage 13,000 feet at the bottom of the Atlantic Ocean, there's a half-size model of it that you can visit in Branson.
The Titanic Museum Attraction features scaled-down replicas of the hallways, parlors, cabins, and first-class suits of the original Titanic. There are also interactive exhibits and over 300 artifacts inside the museum, which is open all year round. You can tour the entire place at your own pace and experience the so-called Titanic mania.
The Butterfly Palace and Rainforest
Witness the colorful butterflies as they flit around the Butterfly Palace and Rainforest in Branson. This tropical-themed attraction houses over 50 species of butterflies from Costa Rica, Ecuador, Malaysia, and other parts of the world.
Watch a 3D film to learn more about the butterflies in the area or feed the lovely critters with a nectar flower. You can also journey through a rainforest where you can find plants, tropical birds, reptiles, and amphibians.
Among the top 30 tourist attractions in this town, you'll surely find something that moves your heart and mind here. It's like a place straight out of a fairytale, so if you have kids, see to it that you bring your little ones to the Butterfly Palace and Rainforest.
Designed as an 1880s theme park, the Silver Dollar City offers a fun and thrilling experience to its visitors. The theme park features over 60 restaurants and shops, 40 daily live shows, and 40 amusement rides. You can also learn crafts, such as woodworking, glassblowing, ceramics, and candy making here.
The most well-known rides in Silver Dollar City are Thunderation, Powder Keg, Time Traveler, Wildfire, Fire in the Hole, and Frisco Silver Dollar Line Steam Train.
World's Largest Toy Museum Complex
Children and kids-at-heart will call this place heaven because over a million toys are displayed here. You can find toys from the early 1800s up to the present in this museum. From Barbies and G.I. Joe toys to Matchbox cars and Disney toys, you have it all in the Toy Museum Complex.
The entire complex is composed of eight museums. You have the World's Largest Toy Museum, Wild West Museum, Paul Harvey Jr. 50's Era Museum, Stearnsy Bear Museum, Dolly Mama's Museum, National BB Gun Museum, H.B. Wright Shepherd of the Hills Museum, and World of Checkers.
Branson is a perfect vacation destination because it has a bonanza of tourist attractions that you'll cherish in your lifetime. All the fun, thrill, excitement, awesomeness, and entertainment are to be found in this beautiful town. So, pack your things and book a trip to Branson if you're looking for an extraordinary and unforgettable vacation.
Map of Branson Missouri
Deadwood South Dakota Travel Guide
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Opera Season In Verona


Bradford Bradsea Bda Trademark Details
Bradford Bradsea Bda was registered on Tuesday, December 26, 1950 and is currently owned by Bradford Syeing Association (U. S. A.) under the registration number 535471 . This mark is dead with a status of Expired. The last case file activity for this mark occured 26 years ago on Tuesday, November 3, 1992, according to the United State Patent & Trademark Office
Bradford Bradsea Bda
Dead Registered 900 — Expired
Bradford Syeing Association (U. S. A.) of Westerly, RI
View all trademarks for Bradford Syeing Association (U. S. A.)
No Claim Being Made to the Exclusive Useof the Word "Bradford" Apart from the Mark as Shown.
Rendering Elastic Yarn Goods Satisfactory for Swim Suits by Special Process Which Preserves the Elasticity of the Rubber and Precludes Excessive Stretching and Shrinking
040 — Class 40 includes mainly services not included in other classes, rendered by the mechanical or chemical processing or transformation of objects or inorganic or organic substances. For the purposes of classification, the mark is considered a service mark only in cases where processing or transformation is effected for the account of another person. A mark is considered a trade mark in all cases where the substance or object is marketed by the person who processed or transformed it.
9 — Expired
First Use Anywhere
First Use In Commerce
First use anywhere for the mark
First use in commerce for the mark
Trademark officially registered with the USPTO
Registered and Renewed (first Renewal - 20 Yrs)
Expired Sec. 9


Ben Stein's Diary
Staying Out of the Cold
by Ben Stein
Here I am on The Eastern Sho' again. It's fantastically cold. Just cruel. My driver and dear pal, Bob Noah, and I, drove over to Oxford after I flew into DCA last night from LAX on a superfast four-hour flight. We went to the First Episcopal Church in Oxford, rested in the Parish House, and then I tried to make my usual walk to the Robert Morris Inn, about a mile away down the cutest, most cheerful streets on earth. Small frame homes with Christmas lights and candles and happy people waving to me as I passed by.
But it was far too cold and I gave up quickly and had Bob drive us to the Inn and to Salter's, the fabulously great restaurant in it. There was a roaring fire next to our seat in the centuries-old dining room. The crab courses were all marvelous and the service as cheerful as ever. There's no better, more comforting place to eat than Salter's. I especially recommend the liver.
Then, back to the car. I fell asleep immediately, as I usually do. When I awakened, we were at McDonald's in Kent Narrows. For some reason I felt the need for a cheeseburger. I ordered one freshly made and it was heavenly. McDonald's is a sort of miracle for travelers. Consistently good, cheap, friendly, with tasty food. You can't beat a freshly made cheeseburger for taste. A retired Air Force Colonel drinking a milkshake lavished praise on me, so I love that restaurant even more than before.
Then, back to DC. I felt like having soup, so we went to a new place with branches all over DC Metro. It's called Founding Farmers. It was mobbed with diners of all races and ages. This is something I marvel at and love. There is real racial integration in DC in restaurants. It's like a dream come true. I never see any integrated clientele in LA or the desert or almost never.
I had dee-lish tomato soup and then went out into the frigid night. A poor crippled homeless black man was standing at the door begging. A well-dressed woman gave him her left over sandwich. "I need fifteen dollars for a room," the man said with startlingly good articulation. I gave him the fifteen dollars. That seemed like little enough to do but he continued to stand at the door begging. Hmmm.
Back home to my glorious apartment at The Watergate to watch "The Great Gatsby" for the billionth time. Too much Gatsby. I turned to the AHC channel for ever more on Hitler. What a fascinating, crazy, evil man. But mesmerizing. Pure evil. But, again, mesmerizing.
I watch the commercials with special interest. There is a black person or a Hispanic or an Asian in almost every one. TV offers to the world an alternative reality of an integrated America. Three-fourths of white Americans do not have a single black friend. But on TV, the world is fully integrated. And the blacks on TV are well off, middle class, jocular. Black "Ozzie and Harriet." Black "Father Knows Best." Black "Perry Mason." They're in big suburban homes (at least in the commercials). They're drinking expensive alcohol. They're investing to live it up after retirement. They're driving Benzes.
Madison Avenue and Hollywood are working feverishly to create a new alternative reality for non-white Americans. I think it's a great idea. It gives non-whites an idea of what their lives can be like if they… if they… well, if they get educated and start businesses and move up to the East Side, to a DEE-LUXE apartment in the sky, like George Jefferson. Unlike the Obama world, where blacks were in a condition of permanent grievance, the blacks on TV have made it and are living happily.
These shows, these commercials, offer motivation to work hard, to study, to learn useful skills, to stay married. I don't think TV can do a more important service than what it's doing now: showing non-whites a better way if they care to take it.
It's motivation to get ahead. Plus, the alternate reality of integrated America on TV shows whites that blacks are not to be frightened about. They have the same dreams as whites do. (By the way, I wonder who writes these commercials…) Anyway, it's a way for TV to make itself useful.
Friday.
Dinner with a very close personage whom I had traveled across the country to see. She basically had only one thing to say: how fat yours truly is and how pitiful I looked. I told her, truthfully, that this pitiful look was largely because of exhaustion dealing with the new Trump tax laws. That didn't get me off the hook. My interlocutor fixed me with a steely grip and told me I was about to die if I didn't go to Overeaters Anonymous. I was so hurt and angry I was shaking all night.
My critic is right. I am an insane overeater. But people do not like to be told they're overweight. That's a good lesson to be learned. They don't like to be told they're deplorable and they don't like to be told they're fascists and they don't like to be told they're fat.
There's a lesson here. You do not get a pass for honesty for telling people what they don't want to hear and no one wants to travel 2600 miles to see someone and have that someone tell him he's fat. But critics are often our best teachers and I will try not to gorge myself as much as I usually do. A hard habit to break though. Very close to impossible. Food is the ultimate drug.
A viciously long return flight to LAX. Immense, cruel headwinds. The trip went on forever. I used the time though to read about Trump in the Journal and in the NY Times. They might as well be reporting from different galaxies. Trump is a sinister buffoon and blood sucker of the poor in the Times. He's doing a lot right in the Journal. The Times just wears a permanent sneer about Trump. One big long sneer of the Beautiful People for a rich man who relishes harming people but has no class at all. Not like the blue bloods in the Times newsroom. The hatred of Trump is so intense that it verges on mania. "All history is the history of class struggle," said Mr. Marx. I think it's really more like crazy people getting control of countries and movements and putting their craziness into action — Marxism, Nazism, anti-Semitism. Angry people setting nations onto courses of anger. And yet even the Germans were somber when they learned Germany had invaded Russia in June of 1941. There is some wisdom left, some residuum of common sense, even in a Nazi Germany. Do we have enough left here in America to get us through our difficulties ? The problem now is that the nut cases are in the media and the academy pretending to moral superiority. Wait a minute. That's always the problem. The killers pretending to moral superiority and the "useful idiots" (like me when I was at Yale) applauding the killers as morally better than the USA.
Stalinism. Premature anti-fascism. Alger Hiss's many friends.
"Your basic human is not such a hot item," says my very smart sister. She's right on, as usual. A powerful critic of the human species.
By the way, on the plane, I watched a genuinely insane movie: The Accountant, about a mentally ill accountant, killer, saver of lost lives, Airstream owner. It is a crazy movie but fun to watch. Too much violence, though.
I'm back in LA. It's freezing everywhere else. But here in LA, I swam for half an hour in my pool this morning before my 12 step meeting for overdoing it. God bless LA and God bless Trump. But what's keeping him from busting the sequester and re-arming America? This is Job One, Mr. Trump. We love you, but you promised to rearm and it's high time.
I'm going to sleep now so I can swim in the morning. And then eat only an Ensure. Just one little Ensure.
Butter Pecan.
Follow Their Stories:
Ben Stein is a writer, actor, economist, and lawyer living in Beverly Hills and Malibu. He writes "Ben Stein's Diary" for every issue of The American Spectator.


What Is Singapore Maths?
Maths At Singapore
Singapore has become a "laboratory of maths teaching" by incorporating established international research into a highly effective teaching approach. With its emphasis on teaching pupils how to think critically to solve problems and consistently topping math results worldwide, Singapore MOE Math teaching is the envy of the world.
Plus, with more workers engaging in remote work and students learning remotely, online Singapore MOE (Ministry of Education) math classes are in high demand. So, just what exactly is Singapore MOE Math?
The Basis of Sinagpore MOE Math
The Singapore MOE Math refers to the primary school math program that is developed by the Singapore Ministry of Education (MOE) and taught in all Singaporean public schools. An important pedagogical approach in this program is the Concrete, Pictorial, and Abstract (CPA) method.
As its name suggests, the CPA learning model incorporates three steps that build on one another, reinforcing what your child will learn in our online Singapore MOE Math classes:
The concrete involves an actual object like coins.
The pictorial refers to a visual representation, such as a picture of these coins on paper.
The abstract culminates in your child solving math problems without aids.
This is what and how we teach at Maths@Singapore, as it provides your child with a deeper understanding of the math problem.
Singapore's MOE Math Method and Results At A Glance
Singapore consistently tops the international benchmarking studies for math teaching
It is a highly effective approach to teaching math based on research and evidence
Singapore MOE Math enhances students' mathematical fluency without the need for rote learning
The math method slowly introduces new concepts using the CPA approach
Pupils learn to think mathematically, as opposed to reciting formulas they do not understand
The Singapore MOE Math method teaches mental strategies to solve math problems such as drawing a bar model
Singapore developed a new way of teaching math following their poor performance in the international league tables in the early 1980s. What this led to, is the Singapore Ministry of Education decided to take the best practice research findings from the West and apply them to the classroom with transformational results.
But what about concrete results? Well, where we can see this is in the outcomes of Singapore MOE Math students. The effectiveness of this approach is demonstrated by their position at the top of international benchmarks such as TIMSS (Trends in International Mathematics and Science Study) and PISA (OECD Programme for International Student Assessment). It is no wonder why the Singapore MOE Math program is now used in over 40 countries, including the United Kingdom and the United States.
Program Based on Established Theories
Besides helping to strengthen children's understanding of math concepts, Singapore MOE Math incorporates teaching children how to develop a growth mindset and apply it to their math studies. According to psychologist, Carol Dweck, a growth mindset is the belief that one can change their behavior or solve a problem if they apply themselves. This is the opposite of a fixed mindset, where an individual believes that their abilities, personality, and circumstances cannot be changed and that there is nothing they can do about it.
Having a growth mindset is crucial to children, even more so to students who have poor math results and tell themselves that they can't improve. What is even more impressive, is that your child can apply a growth mindset to anything else they wish to accomplish.
About Maths At Singapore – Our Story
What Maths@Singapore aims to achieve is nurturing every one of our students in effectively mastering the math fundamentals for their age, enabling them to grow into confident math learners who love the subject. With our online math classes, Maths@Singapore also endeavors to have our pupils recognize the value of math in their everyday lives.
It is for this reason that Maths@Singapore was first conceived by a Stanford alumni who is also a parent of two young children.
His child started her primary school education in a US elementary school during his time at Stanford, before returning to attend a Singapore (MOE) Ministry of Education primary school. What he observed firsthand—the rigor and effectiveness of the Singapore MOE math program in growing his child to be a better and more confident math learner, as compared to her progress in her previous school—is what convinced him to start Maths@Singapore.
He believes that math is fundamental to the many technologies solving the world's greatest challenges, and making people's lives better. After all, math is one of the core subjects of medicine, biology, physics, and engineering. And these all contribute to the benefit of society and human flourishing as a whole.
He, therefore, believes Singapore MOE Math is important to help our children understand and gain the confidence to use math. Apart from helping learners accomplish good grades in school, Maths@Singapore's online math classes help them better understand (and appreciate) the world around them. Plus, it inspires them to be the next generation of scientists, construction managers, and engineers the world needs. They say "the children are the future," and investing in their education, particularly math, is important.
Together with his friend, they founded Maths@Singapore to help American children become better math learners through the combination of what the effective Singapore MOE math program teaches, expert Singaporean teachers, and an effective online classroom learning environment.
Looking at signing your child up for online math tuition but do not know where to start? Not to worry. You are more than welcome to email us to speak to one of our professionals and learn more about Maths@Singapore. While you are at it, why not sign up for 2 free classes and see for yourself the difference between Singapore MOE Math and Common Core?


Box Era Releases "Brunches," New Single From Upcoming EP
Posted by Elise | Jan 26, 2017 | Jam Band News, Music Corner | 0 |
Written by Elise Olmstead
It's an exciting time for College Park based band, Box Era, as they are working on their debut EP and hitting the ground running with a tour to support. They'll be playing with popular local jam bands such as Fractal Cat, Gang of Thieves, and ELM, their show with ELM coming up this Saturday January 28th.
Founded in early 2015, Box Era is still a fairly new band, but their sophisticated sound sings of years of experience. Appalachian Jamwich was excited to listen to their first track, "Brunches," released off their upcoming EP. The EP is not yet titled, and was recorded in multiple locations in the DMV.
"Brunches" is a sensual, jazzy tune, with notes of R&B. "Brunches was one of the first songs we wrote, and it's our go-to sensual slow jam." The track includes sultry vocals and sexy saxophone, tempting the listener to close their eyes and be carried away to bliss. "The lyrics basically just talk about appreciating the value within a fleeting relationship, regardless of the relationship's intensity. We cross paths with a lot of people in our lives, most for just brief moments. It's interesting to think how the person you just held the door for will probably never see you again."
The EP will not be all slow jams, though, and the band insists it will be a dance party. The songs being recorded have all been tested on the road and will be reminiscent of a live show. "Because it's our debut, we wanted to give people a refined version of what they've seen us do live."
Listen to their single, "Brunches," and catch them at a show coming near you. You'll want to keep your eye on Box Era, as they are headed for big things!
Listen to "Brunches": https://soundcloud.com/boxeramusic/brunches
RSVP to the show on Saturday with ELM at Jammin Java in Vienna, VA: https://www.facebook.com/events/1864607793777055/
More upcoming shows:
1/28: Jammin' Java, Vienna, VA w/ ELM (Electric Love Machine)
2/3: BeClaws, Wheaton MD
2/22: Gypsy Sally's, Washington, D.C. w/ Gang of Thieves
3/4: Dante's, Frostburg, MD w/ Fractal Cat
PreviousInterview: AJ talks to Pink Talking Fish about Feb 3 show at The Capitol Theatre, Port Chester, NY
Next"The Contribution" To Release New Music Throughout The Year
Creative Director of The Jamwich.
2nd Annual Halloween Bash Featuring LITZ, Plaeground and The Jambulance
Catskill Chill Announces New Dates for 2015 and "A Farewell To Minglewood"
Relentless Beats Announces the Return of Goldrush Music Festival, with New Dates – this September 29 & 30
Festival Spotlight: Spun Out Fire Presents Nights of Fire Aug 17-21, 2017


Chorus Aviation Announces Leasing Transaction for Five Q400s to Flybe and Reaches 50 Aircraft Portfolio Milestone
Delivering regional aviation to the world
HALIFAX, May 21, 2019 /CNW/ – Chorus Aviation Inc. ('Chorus') (TSX: CHR) announced today that Chorus Aviation Capital ('CAC') has entered into a purchase agreement to acquire five, mid-life Bombardier Q400 aircraft currently on lease with Europe's largest independent regional airline, Flybe. This transaction is expected to close by this summer and is subject to customary conditions precedent to closing, such as the novation of the existing leases, as well as the receipt of all regulatory approvals or consents required in connection with the acquisition of Flybe by Connect Airways Limited. With these acquisitions, Chorus Aviation Capital has announced 50 commitments to date for its regional aircraft leasing business.
"We are very pleased to expand our relationship with our existing customer, Flybe," said Steve Ridolfi, President, Chorus Aviation Capital. "In less than two years we've grown our leasing portfolio to 50 aircraft acquired at approximately US $995.0 million with US $765.0 million in future contract lease revenue."
"In addition to growing CAC's lease portfolio, these mid-life aircraft play to the Chorus group's strengths as a diversified provider of regional aviation services," commented Joe Randell, President and Chief Executive Officer, Chorus. "At the end of the lease term, Chorus will have multiple potential uses for these aircraft, including lease extensions, re-leases or sale to new operators, conversions to non-passenger use, or disassembly for parts sales. I applaud the Chorus team for reaching this important milestone and for embracing our vision to become a worldwide provider of integrated regional aviation services."
Upon the completion of this transaction, and seven other aircraft pending delivery to other customers, CAC's portfolio will include 38 turboprops and 12 regional jets placed with 13 airlines on six continents. When combined with the 47 aircraft leased under the Capacity Purchase Agreement with Air Canada, Chorus' fleet of leased aircraft has reached 97 aircraft valued at approximately US $1.6 billion.
About Chorus Aviation Capital
Established in 2017, Chorus Aviation Capital currently has relationships with 13 regional airlines based in 13 countries. CAC is focused on building a portfolio of new and mid-life regional aircraft, while leveraging the synergies inherent among its affiliated companies to provide a full suite of regional aviation services.
Headquartered in Halifax, Nova Scotia, Chorus was incorporated on September 27, 2010. Chorus' vision is to deliver regional aviation to the world. Chorus has been leasing its owned regional aircraft into Jazz's Air Canada Express operation since 2011, and established Chorus Aviation Capital to become a leading, global provider of regional aircraft leases. Chorus also owns Jazz Aviation LP and Voyageur Aviation Corp. – companies that have long histories of safe and solid operations that deliver excellent customer service in the areas of contract flying operations, engineering, fleet management, and maintenance, repair and overhaul. Together, the Chorus group of companies can provide a full suite of regional aviation support services. Chorus Class A Variable Voting Shares and Class B Voting Shares trade on the Toronto Stock Exchange under the trading symbol 'CHR'. www.chorusaviation.com
About Flybe
Flybe is the largest independent airline in Europe and carries approximately eight million passengers per year between 81 airports across the UK and Europe, with over 210 routes across 15 countries.
This news release may contain 'forward-looking information'. Forward-looking information is identified by the use of terms and phrases such as "anticipate", "believe", "could", "estimate", "expect", "intend", "may", "plan", "predict", "potential", "pending", "project", "will", "would", and similar terms and phrases. Forward-looking information involves known and unknown risks, uncertainties and other factors that may cause actual results, performance or achievements to differ materially from those indicated in the forward-looking information. Actual results may differ materially from results indicated in forward-looking information for a number of reasons, including the failure to close the transactions referenced in this news release on the terms and conditions currently contemplated by Chorus, or at all, as well the risk factors identified in Chorus' Annual Information Form dated February 21, 2019 and in Chorus' public disclosure record available at www.sedar.com. Statements containing forward-looking information in this news release represent Chorus' expectations as of the date of this news release (or as of the date they are otherwise stated to be made) and are subject to change after such date. Chorus disclaims any intention or obligation to update or revise such statements to reflect new information, subsequent events or otherwise, unless required by applicable securities laws.
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Chorus Aviation Inc. Announces May 2019 Dividend →


Greenville Road Warriors shut out by Florida
Myron Hosea
One night after scoring four goals in a loss, the Greenville Road Warriors drew a blank in a 4-0 defeat to Florida on Saturday night.
The Everblades came into town and won back-to-back games at the Sandlapper Securities Rink in the Bon Secours Wellness Arena. A crowd of 3,938 came out to see the contest.
Despite the zero on their side of the scoreboard, the Road Warriors produced opportunities.
"We had some Grade A chances in the first period," said Greenville coach Dean Stork. "Second period, I thought we outplayed them and had three or four chances right in tight around the net.
"I thought we just lost a couple too many battles around the net, net fronts, being strong on the sticks."
Greenville outshot Florida 32-29. Stopping those 32 Road Warriors shots was newly signed Florida goaltender Anthony Peters. His first professional start turned out to be a shutout.
Greenville (31-24-1-2) missed an opportunity to climb in the ECHL Eastern Conference standings with these two losses. They didn't drop back, though, as Elmira and Orlando were off Saturday.
The Road Warriors are sixth in the conference standings, three points ahead of Elmira and five up on Orlando. The top eight teams at the end of the regular season will make the playoffs. Greenville hosts South Carolina at 3 p.m. today.
Florida moved into a tie for second in the conference with Reading.
"We defended better," Stork said. "Didn't turn over the puck as much. Outshot them. Why weren't we rewarded? I don't know. Some games you're rewarded, and some games you're not getting the bounces.
"We'll just have to continue to put our noses deep and keep digging and fight and battle through it."
The teams played about 30 minutes of scoreless hockey before Florida (36-13-2-4) produced a goal. Mike Little put the Everblades up 1-0 with a goal at 10:55 of the second period.
Florida began putting distance between itself and the Road Warriors early in the final period. Just 10 seconds into a power play opportunity, Brant Harris scored at 1:56.
Then, Alex Lavoie rifled a shot from the faceoff circle left of Greenville goaltender Jason Missiaen. That gave the Everblades a 3-0 advantage at 2:38 of the third.
Florida's last goal came at 18:41 on an empty net goal by Jason Wilson.
Greenville welcomes South Carolina to the Well for the final Sunday afternoon game of the season and the last game between the teams in the regular season.


/ team_photos/callum5cc7171a479b6.jpg Callum Buckland
Customer Enquiries Callum Buckland
Customer Enquiries Assistant
Callum has had an interest in architecture since he was young and visited National Trust properties with family. He studied Architecture at Plymouth University before moving back to his hometown of Portsmouth where he worked in a luxury independent hotel as both an Events Assistant and Duty Manager. With a recent move to London Callum decided to mix his passion for architecture with the customer service skills he learnt in hospitality and joined the practice in early spring.
/ team_photos/dand5497d395c48ad.jpg Dan Davidson
Chief Executive Dan built his first Side Return in 1999 and has lived in a London Victorian house for over 15 years. Dan also enjoys the practical side of construction, having taught himself plumbing shortly after graduating. The son of two environmentalists, Dan is a keen advocate for improving the energy performance of Side Returns and is an avid follower of new technologies within the built environment. Dan also serves as a Trustee to the Board of Groundwork London; a charity established in 1982 to bring together business, communities and government to improve people's prospects, promote greener living and create better places to live.
/ team_photos/david56b082bca3172.jpg David Abimbola
Design Manager David graduated in Architecture from Kingston University in London. He oversees the Architectural Design Team and ensures the smooth running of the Design Process. He loves travelling the world to see how different cultures interpret design. His favourite city (so far) is Chandigarh in India, and he is a keen admirer of Le Corbusier, a French-Swiss Architect.
/ team_photos/stephen581b317582398.jpg Stephen Hill
/ team_photos/marcus58790a98086d7.jpg Marcus Hirst
/ team_photos/steven5696245ba3b46.jpg Steven Davidson
Architectural Designer Steven graduated in 2013 with a Master's degree in Architecture from the University of Edinburgh. During his year out while at university he worked as an architectural assistant at TBB Architecture.
Steven joined Build Team as an Architectural Assistant in 2015. His role includes conducting measured surveys and engaging with design clients, from the initial client visit through to the survey, and producing designs schemes and technical CAD drawings.
/ team_photos/liam25b6407a1b91f7.jpg Liam Davies
/ team_photos/35b8ea39ca7ca1.jpg Arya Sunny
Architectural Designer Arya is originally from India where she studied at Calicut University. She moved to London several years ago and has experience in working in a small residential architectural practice before joining Build Team. She admires simplicity and using true materials in architecture.


Indiana man accused of holding 4 people hostage for 5 days
This undated photo provided by the Elkhart County Sheriff's Department shows Derrick Glass, who is accused of holding four people hostage for five days in Elkhart, Ind. Glass was arrested Tuesday, May 2, 2017, after he allowed one of his alleged hostages to go shopping. (Elkhart County Sheriff's Department via AP) (The Associated Press)
ELKHART, Ind. – A man is accused of holding four people hostage for five days in a northern Indiana city.
Elkhart Police Sgt. Chris Snyder says Derrick Glass confined a 68-year-old man and women aged 64, 26 and 21 against their will in an Elkhart apartment from Friday until Tuesday, but that they were not "tied up or restricted."
Snyder says Glass threatened them all with a handgun and assaulted two of the women with it. No shots were fired.
The 31-one-year-old man was arrested Tuesday after he allowed one of his alleged hostages to go shopping. She reported the situation to police.
The Elkhart Truth reports (http://bit.ly/2pKA8fY ) Glass faces four counts of criminal confinement while armed with a deadly weapon and two counts of aggravated battery. He remains jailed without bond Thursday.
Information from: The Elkhart Truth, http://www.elkharttruth.com


Math expert forecasts divorces
Call it a practical application of social engineering technology…
Professor James Murray of Oxford University has devised a mathematical formula which he says is 94 per cent successful in predicting which newly-wed couples will eventually divorce.
Murray and his research team filmed more than 700 newlywed couples discussing issues deemed likely to cause stress, such as sex and money, for periods of 15 minutes at a time. The researchers then graded the subjects' statements and responses as either positive or negative. The resulting scores were then tallied to determine the likelihood that the relationship would last.
The same couples were contacted again, at one or two year intervals over the next 12 years to see how they were doing. Which is how Murray determined that his predictions, based on the math, had been so amazingly accurate.
"Some couples might as well get divorced right away," Murray told reporters.
There's no word as to whether Murray's formula will be made available, on a commercial basis or otherwise, to marriage counsellors, clergy or others who counsel those preparing to marry. We wonder if there's a mass market for a consumer test in which couples — upon payment of an appropriate fee, of course — could film themselves discussing specified topics, post the results to an official analysis Web site and, then, get back a report on their long-term prospects. We want stock in that company…


Operations Suspended: Muskogee Plant Closed To Workers After Explosion
Tuesday, May 14th 2019, 6:47 am
Muskogee Firefighters are still on scene at Georgia Pacific Tuesday afternoon after a propane forklift caught fire and exploded.
Related Story: UPDATE: Explosion At Georgia-Pacific In Muskogee
No one is injured but employees say the explosion has them wondering what the future will hold for them at the company.
It's a huge plant so there are employees in different buildings that are at work, but the parking lots are also full of employees who used to work in the building that caught fire.
They are on standby right now, waiting to hear when they can go back to work. One man was in the building when the explosion happened, and he said that all the dust came off the walls. He said he has no idea how everyone got out safely.
Firefighters are still on scene, putting out hot spots. Every fire station in Muskogee responded.
A spokesperson for Georgia Pacific said a propane forklift inside caught fire and then exploded. The fire is contained to buildings 27 and 10 but a lot of people who work in those buildings are wondering what this is all going to mean for them.
The Georgia-Pacific spokesperson said they did evacuate the plant despite having a fire brigade that's trained to handle situations like this.
"It's heartbreaking. It's sickening. I just never thought ... my mama always told me tomorrow ain't promised to nobody so don't take nothing for granted. That's what she said. She's right," said former employee Kathy Terrell.
News On 6 Officials say the Georgia-Pacific plant has suspended all operations and no on can go to work as of Tuesday morning.


Home All issues Volume 557 (September 2013) A&A, 557 (2013) A122 Full HTML
Volume 557, September 2013
Stellar structure and evolution
2. Observations and ...
3. Atmospheric parameter ...
4. Atmospheric parameters
5. Helium abundances
6. The 3He isotopic anomaly
Online material
Hot subdwarf stars in close-up view
IV. Helium abundances and the 3He isotopic anomaly of subdwarf B stars⋆
S. Geier1,2, U. Heber1, H. Edelmann1, L. Morales-Rueda3, D. Kilkenny4, D. O'Donoghue5,6, T. R. Marsh7 and C. Copperwheat8,7
1 Dr. Karl Remeis-Observatory & ECAP, Astronomical Institute, Friedrich-Alexander University Erlangen-Nuremberg, Sternwartstr. 7, 96049 Bamberg, Germany
e-mail: sgeier@eso.org
2 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching, Germany
3 Department of Astrophysics, Faculty of Science, Radboud University Nijmegen, PO Box 9010, 6500 GL Nijmegen, The Netherlands
4 Department of Physics, University of Western Cape, Private Bag X17, 7535 Bellville, South Africa
5 South African Astronomical Observatory, PO Box 9, 7935 Observatory Cape Town, South Africa
6 Southern African Large Telescope Foundation, PO Box 9, 7935 Observatory Cape Town, South Africa
7 Department of Physics, University of Warwick, Conventry CV4 7AL, UK
8 Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH 41 1 LD, UK
Atmospheric parameters and helium abundances of 44 bright subdwarf B stars have been determined. More than half of our sample consists of newly discovered stars from the Edinburgh Cape survey. We showed that effective temperatures and surface gravities can be derived from high resolution echelle spectra with sufficient accuracy. Systematic uncertainties have been determined by comparing the parameters derived from the high resolution data with the ones derived from medium resolution spectra. Helium abundances have been measured with high accuracy. Besides the known correlation of helium abundance with temperature, two distinct sequences in helium abundance have been confirmed. Significant isotopic shifts of helium lines due to an enrichment in 3He have been found in the spectra of 8 subluminous B stars (sdBs). Most of these stars cluster in a small temperature range between 27 000 K and 31 000 K very similar to the known 3He-rich main sequence B stars, which also cluster in such a small strip, but at different temperatures. Both the helium sequences and the isotopic anomaly are discussed.
Key words: subdwarfs / stars: atmospheres / stars: abundances / stars: fundamental parameters
Tables 1 and 2 and Appendix A are available in electronic form at http://www.aanda.org
Subluminous B stars (sdBs) have similar colours and spectral characteristics to main sequence stars of spectral type B, but are much less luminous. Strong line broadening and the early confluence of the Balmer series is caused by the high surface gravities (log g ≃ 5.0−6.0) of these compact stars (RsdB ≃ 0.1−0.3 R⊙). SdBs are considered to be core helium-burning stars with very thin hydrogen envelopes and masses of about half a solar mass (Heber 1986) located at the extreme end of the horizontal branch (EHB).
The origin of these stars is unclear. A mass loss mechanism must manage to remove all but a tiny fraction of the hydrogen envelope at about the same time as the helium core has attained the mass (≃0.5 M⊙) required for the helium flash. The reason for this mass loss is still unknown. Several single star scenarios invoke enhanced stellar winds or interaction with the stellar environment (see Heber 2009 for a review).
However, Mengel et al. (1976) showed that the required strong mass loss can occur in a close-binary system. The progenitor of the sdB star has to fill its Roche lobe near the tip of the red-giant branch (RGB) to lose most of its hydrogen-rich envelope. The merger of binary white dwarfs (WDs) was investigated by Webbink (1984) who showed that an EHB star can form when two helium core white dwarfs merge and the product is sufficiently massive to ignite helium.
Maxted et al. (2001) determined a very high fraction of radial velocity variable sdB stars (see also Morales-Rueda et al. 2003; Napiwotzki et al. 2004a; Copperwheat et al. 2011). Han et al. (2002; 2003) used binary population synthesis models and studied the stable Roche lobe overflow (RLOF) channel, the common envelope ejection (CE) channel, where the mass transfer to the companion is dynamically unstable, and the He-WD merger channel.
The formation of sdBs has also been related to the origin of the even more enigmatic He-sdO/Bs (Ahmad & Jeffery 2003; Naslim et al. 2010; Ströer et al. 2007; Hirsch & Heber 2009). The so-called late hot flasher scenario was proposed to form these objects (Lanz et al. 2004; Miller-Bertolami et al. 2008).
At first glance, determining the helium abundance in sdB atmospheres seems to be the best diagnostic tool to distinguish between the different formation channels. While the merger of two He-WDs would form a pure He-star, a wide range of helium abundances is predicted by the late hot flasher scenario. Different mass-loss on the RGB, either triggered via single-star or binary evolution, may also leave an imprint on the helium abundance of the formed sdB.
Unfortunately, the primordial helium abundance of sdB stars is significantly affected by processes in the hot and very dense atmospheres of these stars. Sargent & Searle (1966) found sdB stars to be helium deficient for the first time. Greenstein et al. (1967) suggested that diffusion might cause the observed helium deficiency. However, theoretical diffusion models yielded only little success (e.g. Michaud et al. 1983), since the timescales for the gravitational settling were predicted to be too short. The atmospheres of sdBs should not only be depleted in helium, but essentially helium-free. Several attempts have been made to model the atmospheres of sdBs by invoking radiative levitation and mass loss caused by stellar winds to counteract the gravitational settling (Bergeron et al. 1988; Michaud et al. 1989; Fontaine & Chayer 1997; Ohl et al. 2000; Unglaub & Bues 2001).
Diffusion not only affects the elemental abundances, but can also lead to a separation of different isotopes. When a heavier isotope is significantly affected by gravitational settling, the lighter one appears to be enriched in the atmosphere. An enrichment of 3He has initially been found in main sequence B stars with subsolar helium abundance (Sargent & Jugaku 1961; Hartoog & Cowley 1979) and explained by diffusion processes (Vauclair et al. 1974). Feige 86 was the first horizontal branch star showing this anomaly (Hartoog 1979). Eventually Heber (1987) detected strong line shifts in the sdB star SB 290 and the blue horizontal branch star PHL 25 indicating that basically the whole helium content of the atmosphere consists of 3He. Later, Edelmann et al. (2001) and Heber & Edelmann (2004) found another three sdBs (Feige 36, BD +48 2721, PG 0133+114) where 3He is enriched in the atmosphere.
Finally, diffusion may change the atmospheres of hot subdwarfs in an even more substantial way. Miller-Bertolami et al. (2008) argued that due to diffusion processes He-sdOs will turn into hydrogen rich subdwarfs before they evolve towards the white dwarf graveyard. The discovery of sdBs with He abundances between the normal sdBs and the He-rich ones seems to be consistent with this scenario (Ahmad et al. 2007; Vennes et al. 2007; Naslim et al. 2011; 2012).
In this paper, we determine the helium abundances and isotopic shifts caused by enrichment of 3He of 44 sdBs from high-resolution spectroscopy. Previous papers of this series dealt with the rotational properties of sdB binaries (Geier et al. 2010, Paper I), the rotational properties of single sdBs (Geier & Heber 2012, Paper II) and the metal abundances of sdBs in the context of diffusion (Geier 2013, Paper III).
In Sect. 2 we give an overview of the observations taken with different instruments. The determination of the atmospheric parameters and helium abundances as well as an evaluation of the uncertainties are described in Sect. 3. In Sects. 4–6 we present our results regarding the atmospheric parameters, helium abundances and isotopic shifts, which are discussed further in Sect. 7. Finally, a summary is given in Sect. 8.
2. Observations and data reduction
39 bright subdwarf B stars were observed with the FEROS spectrograph (R = 48 000, 3750−9200 Å) mounted at the ESO/MPG 2.2 m telescope in La Silla. The spectra were downloaded from the ESO science archive and reduced with the FEROS-DRS pipeline under the ESO MIDAS context in optimum extraction mode. The single spectra of all programme stars were RV-corrected and co-added in order to achieve higher signal-to-noise.
Five stars were observed with the FOCES spectrograph (R = 30 000, 3800−7000 Å) mounted at the CAHA 2.2 m telescope and the spectra were also reduced with the MIDAS package.
Medium resolution spectra of 12 stars were obtained with the ISIS spectrograph (R ≃ 4000,λ = 3440−5270 Å) mounted at the WHT. Nine sdBs discovered in the course of the Edinburgh-Cape blue object survey (Stobie et al. 1997; Kilkenny et al. 1997; O'Donoghue et al. 2013) have been observed with the grating spectrograph and intensified Reticon Photon Counting System on the 1.9 m telescope of the SAAO (R ≃ 1300,λ = 3300−5600 Å). Spectra of five sdBs have been taken with the CAFOS spectrograph mounted at the CAHA 2.2 m telescope (R ≃ 1000,λ = 3500−5800 Å). Table 1 provides a detailed overview of the observed sample and the data.
3. Atmospheric parameter determination and systematic effects
3.1. High-resolution echelle spectra – known issues
Most spectroscopic studies of sdB stars have relied on low and medium-resolution data (R ≃ 500−4000). Fitting model atmospheres to high signal-to-noise ratio (S/N) data allows us to determine Teff and log g with formal uncertainties lower than the systematic effects between different model grids (Green et al. 2008; Heber et al. 2000). This standard technique yielded key results on which our current understanding of sdB formation and evolution is founded (e.g. Heber 1986; Heber & Langhans 1986; Saffer et al. 1994; Maxted et al. 2001; Edelmann et al. 2003; Green et al. 2008; Østensen et al. 2010; Copperwheat et al. 2011; Vennes et al. 2011; Geier et al. 2011b; Németh et al. 2012).
On the other hand, high resolution echelle spectrographs (R > 10 000) are widely used in astronomy today. However, data reduction and analysis of echelle spectra is difficult. Even if sophisticated data reduction pipelines are available, issues such as fringing, extraction errors, insufficient order merging and normalisation remain. Due to the low luminosity of sdBs, echelle spectroscopy of these objects is rather challenging, as only a few of them have magnitudes brighter than 10th. Furthermore, sdBs are hot stars and the most important lines for their analysis are found in the bluest parts of optical spectra; unfortunately, echelle spectrographs are often not very sensitive in the blue, particularly where fibre-feeds are used.
The spectra of sdBs are dominated by strong and broad hydrogen Balmer lines, which are the key to deriving their atmospheric parameters. Since these lines are usually broader than the single echelle orders, merging errors can severely affect the parameter determination and suspicious features can be hard to spot, particularly in low S/N data. However, Lisker et al. (2005) successfully analysed high resolution spectra of sdBs observed in the course of the ESO-SPY project (Napiwotzki et al. 2003). In this case, the UVES spectrograph at the ESO-VLT was used, which is very sensitive in the blue wavelength range. Furthermore, rectification of the data was done by dividing by the featureless spectra of DC-type white dwarfs. However, most of the known DC white dwarfs are too faint to be observed with 2 m-class telescopes and it is therefore not clear, in general, whether reliable atmospheric parameters of sdBs can be derived from medium S/N (30–50), high resolution echelle spectra.
3.2. Determination of atmospheric parameters
Example fit of LTE models to the Balmer and selected He i lines in the FEROS spectrum of EC 03591−3232.
Atmospheric parameters and helium abundances of our sample have been determined by fitting model spectra to the hydrogen Balmer and helium lines of the high-resolution spectra using the SPAS routine developed by H. Hirsch (see Fig. 1). The method is described in Copperwheat et al. (2011). To derive the atmospheric parameters we used local thermodynamic equilibrum (LTE) model with solar metallicity for stars with effective temperatures between 24 000 K and 30 000 K. The hottest stars with Teff > 30 000 K have been fitted with LTE models with supersolar metallicity (see Copperwheat et al. 2011).
Due to the high resolution of the spectra the formal errors derived with a bootstrapping algorithm are much smaller than the typical systematic offsets between different model grids (ΔTeff ≃ 500 K, Δlog g ≃ 0.05). However, these formal uncertainities must not be adopted as error estimates, because systematic shifts are the dominant error source in this case.
3.3. Comparison with medium resolution data
Due to the caveats discussed in Sect. 3.1, the parameter determination from the high-resolution spectra needs to be checked and systematic effects have to be quantified properly. We used medium-resolution spectra obtained with the ISIS, the SAAO-Reticon and the CAFOS spectrograph and analysed them in the same way as the high-resolution data.
The ISIS and CAFOS spectra have a very high S/N (>100) and cover the blue spectral range down to the Balmer jump. These spectra are perfectly suited for the determination of atmospheric parameters. Again, formal errors are much smaller than the typical systematic offsets between different model grids, which are adopted as error estimates in this case. The SAAO-Reticon spectra also cover the higher Balmer lines, but their quality is inhomogeneous. Although the formal fitting errors can be large – ranging from 700 K to 2000 K in Teff and from 0.12 to 0.28 in log g – they provide a valuable consistency check for the results derived from the high-resolution data.
Figures 2 and 3 show the comparison between the high-resolution and the medium-resolution parameters. In general, the consistency between the parameters derived from high- and medium-resolution data is reasonable.
Effective temperature derived from high-resolution spectra plotted against effective temperature derived from medium resolution spectra (ISIS, SAAO-Reticon, CAFOS). The dotted lines mark the average deviation between the two datasets. The size of the points scales with the data quality of the high-resolution spectra.
Surface gravity derived from high-resolution spectra plotted against surface gravity derived from medium-resolution spectra (see Fig. 2).
Teff − log g-diagram for the entire sample under study. The helium main sequence (HeMS) and the EHB band (limited by the zero-age EHB, ZAEHB, and the terminal-age EHB, TAEHB) are superimposed with EHB evolutionary tracks for solar metallicity taken from Dorman et al. (1993) labelled with their masses. Open symbols mark objects where isotopic shifts due to an enrichment of 3He were detected, filled symbols objects with atmospheres dominated by 4He. The diamonds mark stars belonging to the upper helium sequence, the circles stars belonging to the lower sequence (see Fig. 5). The triangles mark the three sdBs with enriched 3He from literature (Heber et al. 1984; Edelmann et al. 1999; Morales-Rueda et al. 2003).
In order to quantify the uncertainties in the parameter determination, the averages of the shifts with respect to the parameters derived from medium-resolution spectra have been calculated; these are ΔTeff ≃ 1100 K and Δlog g ≃ 0.12. The high resolution spectra of PG 1616+144, PG 1710+490 and PG 2205+023 have S/N values below 30 and hence show large deviations especially in Teff (up to 3500 K). These stars have been excluded before calculating the average. Although not perfect, the above uncertainties are consistent with values found in the literature (see Appendix A).
The atmospheric parameters of all 44 programme stars are shown in Table 2. The final parameters are derived either from high S/N ISIS and CAFOS spectra, if available, or from high-resolution spectra obtained with FEROS and FOCES. The Teff − log g-diagram of the whole sample under study is shown in Fig. 4. All stars are concentrated on or above the EHB, fully consistent with theory, and we therefore conclude that the atmospheric parameter determination is of sufficient quality (see also the comparison with independent determinations from the literature given in Table A.1).
High resolution spectra are very well suited for measuring accurate elemental abundances of sdBs, because the rather weak lines of helium and metals are fully resolved. We therefore used the FEROS and FOCES spectra to determine the helium abundances of our programme stars. The formal uncertainties are very small (Δlog y = 0.01 − 0.07) and comparable to the deviations measured when analysing several single spectra of one object. Taking systematic effects into account the helium abundances should therefore be accurate to ≃0.1 dex. The results are given in Table 2.
Figure 5 shows the helium abundances of our sample plotted against effective temperature. All but two of our programme stars have the subsolar helium abundances typical of sdB stars. Edelmann et al. (2003) reported a correlation of helium abundance with temperature, which was subsequently confirmed by Lisker et al. (2005) and Németh et al. (2012). This correlation can be clearly seen in our sample as well.
Edelmann et al. (2003) also reported the discovery of two distinct sequences showing a similar correlation with temperature. The "low sequence" is offset by about 2 dex from the "high sequence". Lisker et al. (2005) and Geier et al. (2011b) could not confirm this finding, but the sample size of these studies was smaller than that of Edelmann et al. (2003). Németh et al. (2012) studied a sample of bright hot subdwarfs spanning the whole temperature and helium abundance range from sdBs to He-sdOs and found indications for the two distinct sequences although, in their sample, the lower sequence appears to be less steep than reported by Edelmann et al. (2003).
The two distinct sequences are also visible in our data and combining these with the results of other studies (Saffer et al. 1994; Maxted et al. 2001; Edelmann et al. 2003; Morales-Rueda et al. 2003; Lisker et al. 2005; Østensen et al. 2010; Geier et al. 2011b; Németh et al. 2012) the underlying pattern becomes more apparent. In Fig. 5, all of these results are overplotted with the two regression lines calculated by Edelmann et al. (2003) as well as the regression line for the lower sequence calculated by Németh et al. (2012) based on their results spanning a larger range in effective temperatures and helium abundances. The two lines by Edelmann et al. (2003) match very well with the sequences seen in our sample, while the line by Németh et al. (2012) is slightly different. However, as has been correctly pointed out by Németh et al. (2012), those lines are only very crude tentative models, which certainly do not reflect the real complexity of the underlying data.
Defining a dividing line between the two helium sequences by eye, which follows the relation log y = 0.127 Teff/1000 K − 6.718, the numbers of stars belonging to the different sequences can be counted. From our sample of 44 stars, 31 of them (70%) are associated with the upper sequence while 13 (30%) belong to the lower one. The respective fractions of the full sample of 383 sdBs are 82% and 18%, but the full sample is likely to be biased against low helium abundances because most analyses are based on low- and medium-resolution spectra where weak He lines are often not detectable. We therefore regard the respective fractions derived from our sample to be more reliable.
The high-resolution spectra are also perfectly suited to search for small shifts in the rest wavelengths of the helium lines due to the enrichment of 3He. Wavelength shifts can be caused by different effects (for example, the presence of magnetic fields or pressure shifts in high density environments), but the helium line shifts caused by the enrichment of 3He can be modelled quite accurately and show a typical pattern. While some lines like He i 5876 are only shifted by 0.04 Å towards redder wavelengths, the shifts of He i 4922 and He i 6678 are significant (0.33 and 0.50 Å respectively; Fred et al. 1951; given in Hartoog & Cowley 1979). Displacements of this order can be easily detected in high resolution spectra.
All of the stars in our sample have been examined and in 8 cases, isotopic shifts due to the presence of 3He are clearly visible (Figs. 6, 7). One of these (BD+48 2721) has already been discovered by Edelmann et al. (2001).
Helium abundance log y plotted against effective temperature. The filled symbols mark the results from our study. Filled diamonds mark objects where isotopic shifts due to an enrichment of 3He were detected, filled circles objects with atmospheres dominated by 4He. Upper limits are marked with triangles. The solid horizontal line is drawn at solar helium abundance. The two dashed lines are regression lines for the two distinct helium sequences taken from Edelmann et al. (2003). The dotted regression line for the lower sequence is taken from Németh et al. (2012). Measurements taken from literature are plotted as grey symbols.
7.1. Helium sequences
The reasons for the correlation of the helium abundance with temperature and the bimodal structure in the Teff − log y diagram are unknown, although several suggestions have been made and are discussed briefly below.
Photospheric convection has been proposed as the cause of the relative enrichment of helium in sdB atmospheres towards higher temperature. Greenstein & Sargent (1974) suggested that a He+/He2+ convection zone could transport helium from deeper layers into the photosphere of subdwarfs hotter than 30 000 K (but see also Groth et al. 1985). However, Michaud et al. (2011) calculated complete stellar evolution models, including the effects of atomic diffusion and radiative acceleration, to study the abundance anomalies observed on the hot end of the HB. Their models, which assume extra mixing but no stellar-wind mass loss, are in general agreement with the observed metal abundances of sdB stars (Geier 2013) as well as the helium abundances for Teff > 25 000 K. Furthermore, they show that diffusion effects reach far deeper than the stellar atmospheres themselves and should also be dominant in the He+/He2+ convection zone (Moehler, Michaud, priv. comm.).
According to the Michaud et al. (2011) models, the observed scatter in helium abundance is caused by different HB ages and differences in the initial metallicity of the progenitor populations, but these models predict neither the observed correlation with temperature nor the two helium sequences. If the helium abundance does depend on the age of the sdB, one would expect to see a continuous distribution and not a concentration in distinct sequences.
Aznar Cuadrado & Jeffery (2002) argued that, due to tidal effects, sdBs residing in short-period binaries might have higher photospheric helium content than long-period systems or single stars. Edelmann et al. (2003) suggested that this effect could be responsible for the two helium sequences – and this can be directly tested with the available data. Our current sample of bright sdBs consists mostly of stars in which no radial velocity shifts have been detected and so these sdBs are not in close binaries with stellar mass companions. On the other hand, the target sample for the MUCHFUSS project (Geier et al. 2011b), which aims at finding sdBs with massive compact companions in close orbits, consists only of RV variable stars. From the 51 sdBs drawn from the MUCHFUSS sample, 15 belong to the lower helium sequence, so the fraction of these stars is almost exactly the same as in the sample presented here. The close binary hypothesis can therefore be excluded as an explanation of the helium sequences.
Helium lines of sdB stars. The rest wavelengths of the 4He (solid) and 3He lines (dotted) are plotted as vertical lines. The rest wavelengths of the 3He lines have been taken from Hartoog & Cowley (1979). The stars are highly enriched in 3He, but also show a component of 4He. For comparison, the He lines of SB 815 are plotted in the lowest panel. This star does not show line shifts due to enrichment of 3He.
O'Toole (2008) proposed another possibility: whilst the stars belonging to the upper sequence might be core helium-burning (post-)EHB stars evolving in the way modelled by, for example, Dorman et al. (1993), the sdBs forming the lower sequence could be post-RGB objects without helium burning in their cores. The latter objects are direct progenitors of He-WDs with masses ranging from ~0.2 M⊙ to 0.33 M⊙ and are crossing the EHB on cooling tracks (e.g. Driebe et al. 1998). The only sdB for which the post-RGB nature could be proven unambiguously (using a trigonometric parallax) is HD 188112 (Heber et al. 2003) which also has the lowest helium abundance (log y = −5) ever measured for an sdB. Two candidates of similar low mass have been discovered by Vennes at al. (2011) and Silvotti et al. (2012) but, even though these sdBs also show no detectable helium lines, their post-RGB nature is less well established than in the case of HD 188112. Observational evidence for particularly low helium abundance in post-RGB objects therefore remains weak.
Another way to probe the post-RGB scenario is the comparison of both helium populations in the Teff − log g diagram (O'Toole 2008). In Fig. 8, the stars associated with the upper sequence are plotted. Most sdBs are situated within or close to the EHB band but about 10% are above the EHB – consistent with the standard scenario in which most stars are core helium-burning and therefore residing on the EHB and only a minority are more evolved shell helium-burning objects (Dorman et al. 1993).
The distribution of the helium-poor sdBs is different (see Fig. 9) in that the number density of stars on and above the EHB is similar. In the classical picture, sdBs evolve from the EHB but such an even distribution is not expected because the evolutionary time on the EHB is significantly longer than that for post-EHB evolution (~10 times as long).
Comparing the distribution of the helium-poor sdBs with post-RGB tracks calculated by Driebe et al. (1998), one would expect these objects to be the progenitors of He-WDs with masses between 0.25 M⊙ and 0.3 M⊙. The evolutionary timescales on these tracks scale strongly with mass; while the evolution of an 0.25 M⊙ object takes of the order of 100 Myr, it shortens to only a few million years if the object is more massive (0.3 M⊙). Accordingly, one would expect a higher density of objects with low masses in the Teff-log g diagram (if the formation rate of post-RGB objects does not depend on the mass) but this is not the case – most objects are evenly distributed between the ~0.25 M⊙ and 0.3 M⊙ evolutionary tracks (see Fig. 9).
Comments are as for Fig. 6 except that in these stars, the helium lines are entirely shifted to the 3He rest wavelength and no traces of 4He are visible. For comparison, the He lines of SB 290 are plotted in the lowest panel. This star is the prototype of sdBs enriched in 3He (Heber 1987) but note that the lines show significant rotational broadening (Geier et al. 2013).
Teff − log g-diagram for the sdBs associated with the upper helium sequence (see Fig. 4).
Being aware of this problem, O'Toole (2008) argued that many more He-WDs with masses close to 0.3 M⊙ are formed than objects with even lower masses (e.g. Liebert et al. 2005; De Gennaro et al. 2008) which could compensate for the difference in evolutionary timescales. Given that the 18–29% of the sdB population belonging to the helium poor sequence are all direct He-WD progenitors with an evolution about 100 times shorter than the lifetime on the EHB (≃100 Myr), the formation rate of these objects (neglecting selection effects) would be more than ~20 times higher than the formation rate of core helium-burning sdBs. Even so, the distribution of objects seen in Fig. 9 is still hard to explain with the post-RGB scenario. The crowding near the EHB remains especially suspicious, because evolution should be more or less uniform along the tracks given by Driebe et al. (1998). The lack of objects below the EHB poses a particular problem in this respect. In contrast, a significant number of He-WD progenitors with masses between 0.16 M⊙ and 0.4 M⊙ have been discovered at temperatures below ≃25 000 K and well below the HB (see Kilic et al. 2012 and references therein). We therefore conclude that post-RGB evolution, despite being a very interesting option, is not able to explain all of the observations in a conclusive way.
7.2. Isotopic anomaly
The enrichment of 3He in around 18% of our programme stars also remains unexplained. Figure 4 shows the distribution of these stars in the Teff–log g-diagram, including the three sdBs with isotopic shifts taken from the literature. It can be clearly seen that they cluster in a narrow temperature range between 27 000 K and 31 000 K, with BD+48 2721 (Teff = 24 800 K) being the only exception and – given the uncertainties – this 3He-strip could be pure. The fact that all 3He enriched sdBs belong to the upper helium sequence (Fig. 5) might be a selection effect, because the diagnostic helium lines are too weak to measure the isotopic shifts in the helium-poor stars.
Most 3He sdB stars show clear shifts of the He i line at 6678 Å, indicating that almost all the helium in the atmosphere is 3He. BD+48 2721, EC 12234−2607 and PG 1519+640 show strong lines of 3He blended with weak components of 4He (see Fig. 6) and these three stars cover the whole 3He temperature strip. The isotope ratio is therefore not correlated with effective temperature.
Michaud et al. (2011) predict a mild enrichment of 3He but, due to gravitational settling of the heavier isotope, this should be the case in all sdBs. Hartoog & Cowley (1979) studied the enrichment of 3He in main sequence B stars and discovered a pattern strikingly similar to our results: stars enriched in 3He were found at effective temperatures between 18 000 K and 21 000 K; stars with lower temperatures down to ~13 000 K show slight underabundances in helium with respect to the Sun, while the hotter stars up to ~32 000 K are slighty overabundant in helium. The two known BHB stars with detected 3He isotopic shifts (Feige 86, Teff = 16 400 K; Bonifacio et al. 1995; PHL 25, Teff = 19 500 K; Heber & Langhans 1986) have temperatures close to the strip detected by Hartoog & Cowley (1979).
Teff − log g-diagram for the sdBs associated with the lower helium sequence. The figure is similar to Fig. 4 with additional evolutionary tracks for post-RGB objects plotted as dotted lines (Driebe et al. 1998).
In Figs. 4 and 5 a similar pattern can be seen. The sdBs enriched in 3He occupy a small strip in Teff, within which the helium abundance decreases towards lower temperatures and increases towards higher temperatures.
Hartoog & Cowley (1979) argued that diffusion is responsible for this effect. At low temperatures, the radiation pressure is not strong enough to support helium in the atmosphere. As soon as the temperature reaches a certain threshold value, the less massive 3He can be supported, but not the more abundant 4He, which leads to an enrichment of 3He in the atmosphere. At even higher temperatures, both isotopes are enriched and the isotopic anomaly vanishes as the helium abundance rises (see also Vauclair et al. 1974).
A similar scenario might explain the more compact sdB stars. Focusing on the upper helium sequence in Fig. 5 one can see that the helium abundance is scattering around log y ≃ −2.5 for temperatures below 31 000 K. 3He is enriched at the border region. For temperatures higher than ≃31 000 K the helium abundance is rising.
Finally, radiatively driven stellar wind mass loss might play a role (see, for example, Babel 1996 and references therein), but Hu et al. (2011) derived upper limits for this mass loss to be of the order of 10-15 M⊙ yr-1 to allow sdBs to pulsate. However, even weak and fractionated winds might already affect the abundances in the atmospheres of sdB stars (Unglaub 2008).
Atmospheric parameters and helium abundances of 44 bright sdBs have been determined. We have shown that effective temperatures and surface gravities can be derived from high resolution echelle spectra with sufficient accuracy. Systematic uncertainties have been determined by comparing the parameters derived from the high resolution data with the ones derived from medium resolution spectra. Most stars are core helium-burning, but some sdBs are already in the shell helium-burning phase.
Helium abundances have been measured with high accuracy. Besides the known correlation of helium abundance with temperature, two distinct sequences in helium abundance have been confirmed. The reasons for both the increasing helium abundance with temperature and the bimodal distribution have been discussed, but we are left without a strong conclusion.
Significant isotopic shifts of helium lines due to an enrichment in 3He have been found in the spectra of 8 sdBs. Most of these stars cluster in a small temperature range between 27 000 K and 31 000 K very similar to the known 3He-rich main sequence B stars, which cluster at somewhat lower temperatures. This phenomenon is most probably related to diffusion processes in the atmosphere.
S.G. was supported by the Deutsche Forschungsgemeinschaft under grant He 1356/49-1. D.K. thanks the University of the Western Cape and the South African National Research Foundation for financial support. We thank R. A. Saffer for sharing his data with us as well as N. Hambly and H. McGillivray for their contributions to the EC survey. We also thank S. J. O'Toole, S. Moehler and N. Reindl for fruitful discussions. Finally, we want to thank the referee S. Vennes for helpful comments and suggestions. Based on observations at the La Silla Observatory of the European Southern Observatory for programmes number 073.D-0495(A), 074.B-0455(A), 076.D-0355(A), 077.D-0515(A) and 078.D-0098(A). Based on observations with the William Herschel Telescope and the Isaac Newton Telescope operated both by the Isaac Newton Group at the Observatorio del Roque de los Muchachos of the Instituto de Astrofisica de Canarias on the island of La Palma, Spain. This paper uses observations made at the South African Astronomical Observatory (SAAO). Based on observations collected at the Centro Astronómico Hispano Alemán (CAHA) at Calar Alto, operated jointly by the Max-Planck Institut für Astronomie and the Instituto de Astrofísica de Andalucía (CSIC).
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Target sample and data.
Atmospheric parameters.
Appendix A: Comparison of atmospheric parameters with the literature
Atmospheric parameters of 20 of the sdBs analysed here have also been found in the literature. All parameters derived from model fits to the spectral lines are listed in Table A.1. Given the fact that different methods, models and data were used to determine these parameters, our new results are in general agreement with the literature values. The lower temperature (− 2600 K) Saffer et al. (1994) derived for [CW83] 1758+36 may be more accurate, because our analysis is based on only one FOCES spectrum of mediocre quality, while the spectra used by Saffer et al. (1994) cover the Balmer jump. We reanalysed the spectrum used by Saffer et al. (1994) with our method and confirmed the parameters given in this study (Saffer refit).
The atmospheric parameters of the bright sdB, PG 0342+026, have been determined from its spectral energy distribution by Lamontagne et al. (1987), Theissen et al. (1995) and Aznar Cuadrado & Jeffery (2001). Given the higher uncertainties of this method the derived parameters are consistent with our results within the error limits.
Table A.1
Atmospheric parameters from the literature.
Hot subdwarf stars in close-up view — II. Rotational properties of single and wide binary subdwarf B stars
NLTE spectroscopic analysis of the 3He anomaly in subluminous B-type stars
The subdwarf B star SB 290 – A fast rotator on the extreme horizontal branch
A&A 551, L4 (2013)
Hot subdwarf stars in close-up view — I. Rotational properties of subdwarf B stars in close binary systems and nature of their unseen companions
Hot subdwarf binaries from the MUCHFUSS project — Analysis of 12 new systems and a study of the short-period binary population