Anthony E Wolf Ph D Popular Books
Anthony E Wolf Ph D Biography & Facts
Wolf–Rayet stars, often abbreviated as WR stars, are a rare heterogeneous set of stars with unusual spectra showing prominent broad emission lines of ionised helium and highly ionised nitrogen or carbon. The spectra indicate very high surface enhancement of heavy elements, depletion of hydrogen, and strong stellar winds. The surface temperatures of known Wolf–Rayet stars range from 20,000 K to around 210,000 K, hotter than almost all other kinds of stars. They were previously called W-type stars referring to their spectral classification. Classic (or population I) Wolf–Rayet stars are evolved, massive stars that have completely lost their outer hydrogen and are fusing helium or heavier elements in the core. A subset of the population I WR stars show hydrogen lines in their spectra and are known as WNh stars; they are young extremely massive stars still fusing hydrogen at the core, with helium and nitrogen exposed at the surface by strong mixing and radiation-driven mass loss. A separate group of stars with WR spectra are the central stars of planetary nebulae (CSPNe), post-asymptotic giant branch stars that were similar to the Sun while on the main sequence, but have now ceased fusion and shed their atmospheres to reveal a bare carbon-oxygen core. All Wolf–Rayet stars are highly luminous objects due to their high temperatures—thousands of times the bolometric luminosity of the Sun (L☉) for the CSPNe, hundreds of thousands L☉ for the population I WR stars, to over a million L☉ for the WNh stars—although not exceptionally bright visually since most of their radiation output is in the ultraviolet. The naked-eye star systems γ Velorum and θ Muscae both contain Wolf-Rayet stars, and one of the most massive known stars, R136a1 in 30 Doradus, is also a Wolf–Rayet star. Observation history In 1867, using the 40 cm Foucault telescope at the Paris Observatory, astronomers Charles Wolf and Georges Rayet discovered three stars in the constellation Cygnus (HD 191765, HD 192103 and HD 192641, now designated as WR 134, WR 135, and WR 137 respectively) that displayed broad emission bands on an otherwise continuous spectrum. Most stars only display absorption lines or bands in their spectra, as a result of overlying elements absorbing light energy at specific frequencies, so these were clearly unusual objects. The nature of the emission bands in the spectra of a Wolf–Rayet star remained a mystery for several decades. E.C. Pickering theorized that the lines were caused by an unusual state of hydrogen, and it was found that this "Pickering series" of lines followed a pattern similar to the Balmer series when half-integer quantum numbers were substituted. It was later shown that these lines resulted from the presence of helium, the chemical element having just been discovered in 1868. Pickering noted similarities between Wolf–Rayet spectra and nebular spectra, and this similarity led to the conclusion that some or all Wolf–Rayet stars were the central stars of planetary nebulae.By 1929, the width of the emission bands was being attributed to Doppler broadening, and hence the gas surrounding these stars must be moving with velocities of 300–2400 km/s along the line of sight. The conclusion was that a Wolf–Rayet star is continually ejecting gas into space, producing an expanding envelope of nebulous gas. The force ejecting the gas at the high velocities observed is radiation pressure. It was well known that many stars with Wolf–Rayet type spectra were the central stars of planetary nebulae, but also that many were not associated with an obvious planetary nebula or any visible nebulosity at all.In addition to helium, Carlyle Smith Beals identified emission lines of carbon, oxygen and nitrogen in the spectra of Wolf–Rayet stars. In 1938, the International Astronomical Union classified the spectra of Wolf–Rayet stars into types WN and WC, depending on whether the spectrum was dominated by lines of nitrogen or carbon-oxygen respectively.In 1969, several CSPNe with strong O VI emissions lines were grouped under a new "O VI sequence", or just OVI type. Similar stars not associated with planetary nebulae were described shortly after and the WO classification was adopted for them. The OVI stars were subsequently classified as [WO] stars, consistent with the population I WR stars.The understanding that certain late, and sometimes not-so-late, WN stars with hydrogen lines in their spectra are at a different stage of evolution from hydrogen-free WR stars has led to the introduction of the term WNh to distinguish these stars generally from other WN stars. They were previously referred to as WNL stars, although there are late-type WN stars without hydrogen as well as WR stars with hydrogen as early as WN5. Classification Wolf–Rayet stars were named on the basis of the strong broad emission lines in their spectra, identified with helium, nitrogen, carbon, silicon, and oxygen, but with hydrogen lines usually weak or absent. Initially simply referred to as class W or W-type stars, the classification was then split into stars with dominant lines of ionised nitrogen (N III, N IV, and N V) and those with dominant lines of ionised carbon (C III and C IV) and sometimes oxygen (O III – O VI), referred to as WN and WC respectively. The two classes WN and WC were further split into temperature sequences WN5–WN8 and WC6–WC8 based on the relative strengths of the 541.1 nm He II and 587.5 nm He I lines. Wolf–Rayet emission lines frequently have a broadened absorption wing (P Cygni profile) suggesting circumstellar material. A WO sequence has also been separated from the WC sequence for even hotter stars where emission of ionised oxygen dominates that of ionised carbon, although the actual proportions of those elements in the stars are likely to be comparable. WC and WO spectra are formally distinguished based on the presence or absence of C III emission. WC spectra also generally lack the O VI lines that are strong in WO spectra.The WN spectral sequence was expanded to include WN2–WN9, and the definitions refined based on the relative strengths of the N III lines at 463.4–464.1 nm and 531.4 nm, the N IV lines at 347.9–348.4 nm and 405.8 nm, and the N V lines at 460.3 nm, 461.9 nm, and 493.3–494.4 nm. These lines are well separated from areas of strong and variable He emission and the line strengths are well correlated with temperature. Stars with spectra intermediate between WN and Ofpe have been classified as WN10 and WN11 although this nomenclature is not universally accepted.The type WN1 was proposed for stars with neither N IV nor N V lines, to accommodate Brey 1 and Brey 66 which appeared to be intermediate between WN2 and WN2.5. The relative line strengths and widths for each WN sub-class were later quantified, and the ratio between the 541.1 nm He II and 587.5 nm, He I lines was introduced as the primary indicator of the ionisation level and hence of the spectral sub-class. The need for WN1 disappeared an.... Discover the Anthony E Wolf Ph D popular books. Find the top 100 most popular Anthony E Wolf Ph D books.
Best Seller Anthony E Wolf Ph D Books of 2024
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The Holy Bible - King James Version
King JamesHoly Bible King James Version Few Sample Paragraphs from The Holy Bible eBook, Genesis (OT) 1 Gen. 1 IN the beginning God created the heaven and the earth. 2 And the earth was with...
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Inception of Gold
Lexy TimmsThings are not as bad as they seem. They are worse. Being the personal assistant to a narcissistic actress who just happens to own the key to my family's undoing isn't ex...
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Peace on Earth
Maia RossCrime never takes a holiday. Why should Irma? Irma Abercrombie is an energetic retiree with a shadowy past, a mean right hook, and a profound love of Christmas. Surrounded by seaso...
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Nothing to Hide
Scarlett FinnPrize of a lifetime: travel the world with a celebrity billionaire. Come to LA with us, Roxie… It will be so much fun! We have tickets for a latenight talk show! What could possibl...
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The Scarlet Letter
Nathaniel HawthorneAn Apple Books Classic edition. Hester Prynne lives in infamy. After committing adultery and bearing a child with a man whose name she refuses to divulge, the heroine of Nathaniel ...
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Coffee Girl
Sophie SinclairMackenzie "Kiki" Forbes finds herself in a pickle. Either become her snarky sister's nanny, or move halfway across the country to work as assistanttothestylist of a ...
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Good Guy
Kate MeaderHe's a Special Forces veteran making his pro hockey debut. She's a dogged sports reporter determined to get a scoop. She's also his best friend's widow . . . Fa...
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Saltwater Cove
Amelia AddlerSecond chances...and the secrets that sabotage them. At 48 years old, Margie Clifton never expected to be starting her life all over again. But when her brother gifts her a propert...
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Become A Better Version of Yourself
Ben LeightonThis ebook contains golden nuggets on how to motivate, inspire and improve your current situation. It encompasses the holistic view of self improvement from mental& emotion...
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Holy Bible
The Church of Jesus Christ of Latter-day SaintsThe 2013 edition of the Holy Bible contains all of the study aids contained in the 1979 edition and includes revisions to the study aids, several new photos, updated maps, and adju...
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His Girl Next Door
Khardine GrayFrom USA Today Bestselling author Khardine Gray comes a sizzling hot single dad romance you won't want to miss. No strings attached fun with the ubergorgeous single d...
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Becoming Lady Dalton
Carrie LomaxA dance of desire and deceit... In the glittering world of London's ton, Mrs. Viola Cartwright revels in her newfound freedom as a lady of leisureuntil a series of jewel theft...
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Dream Psychology
Sigmund FreudAn Apple Books Classic edition. Written by the founding father of psychoanalysis, Sigmund Freud’s 1899 book is the definitive text on learning to interpret dreams. Freud’s groundbr...
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Law of Attraction
Jordan HollisHow to Finally Overcome the Hurdles of Manifesting Proven, effective and enjoyable ways to help you manifest faster… Right now, think of something that makes you successful. If you...
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Meditations
Emperor of Rome Marcus AureliusMeditations is a series of personal writings by Marcus Aurelius, Roman Emperor 161–180 CE, setting forth his ideas on Stoic philosophy.
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A Christmas Carol
Charles DickensAn Apple Books Classic edition. It’s Christmas Eve in Victorian England. While some families don’t know where their next meal will come from, Ebenezer Scrooge sits in his large hom...
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Bewitching a Highlander
Roma CordonDefying all for the love of a bewitching lass. Breena MacRae, a healer from Skye with a touch of witchery in her blood, embarks on a dangerous search for her missing father. She ar...
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Finding Cinderella
Colleen Hoover#1 New York Times bestselling author of It Starts with Us and It Ends With Us writes a free novella about the search for happily ever after. A chance encounter in the dark leads ei...
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My Paper Heart
Magan VernonOne piece of paper can change everything After my parents received the letter I failed out of college, they didn't ask questions. They just sent me to work for my great aunt i...
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The Four Loves
C. S. LewisThe Four Loves summarizes four kinds of human loveaffection, friendship, erotic love, and the love of God. Masterful without being magisterial, this book's wise, gentle, candi...
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Salvation
Meghan O'FlynnIf you like mouthy detectives, serial killers, and suspenseful mysteries that don't quit, this chilling and actionpacked hardboiled detective series has you covered! Try this ...
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Just Me
Lexy TimmsWe all need somewhere where we feel safe… After leaving her abusive husband, Katherine Marshall is out on her own for the first time. She's hopped from city to city to avoid t...
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A Bookshop to Die For
M.P. BlackDitching her fiancé at the altar, Alice Hartford bolts to her childhood hometown to reconnect with the last, happy remnant of her past: her mom's old bookstore. But the bookst...
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You Are Kind
Michael GordonA little kindness goes a long way. How can you help encourage your kids to be kind from a young age? Teach kindness to preschoolers Acts of kindness can be fun, easy, and make a ...
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The Wonderful Wizard of Oz
L. Frank BaumAn Apple Books Classic edition. You’ve seen the iconic 1939 movie, but do you know about the talking field mice, the Winkies, and the Witch of the North that appear in the original...
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A Green Kind of Witch
Sierra CrossCinderella crossed with Mean Girls.   That's what Hazel's daily existence feels like. Born to a family of elegant yet shallow Beige Witches, seventeen y...
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Man In The Water
Jon HillAn attempted murder. A missing spouse. And an international conspiracy that could change the world. Jack Green has always been skeptical of socalled facts. Though he's forced ...
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Wuthering Heights
Emily BrontëAn Apple Books Classic edition. If you’ve only ever seen Wuthering Heights on screen, you may have an image of Catherine and Heathcliff as the ultimate starcrossed lovers. But that...
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Pride and Prejudice
Jane AustenAn Apple Books Classic edition. Jane Austen’s beloved classic opens with this witty and very memorable line: “It is a truth universally acknowledged, that a single man in possessio...
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All Fired Up
Kathryn ShayCaptain Jarek Zenko, a war veteran and firefighter, meets Lacey Roth at a bar one night. They don’t share their real identities, even when they retreat to a hotel. When they meet t...
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The Cupcake Cottage
Jean OramNHL player Maverick Blades could fall in love with anyone... But he had to fall for a woman who falls under the Bro Code as untouchablehis best friend’s beautiful ex, DaisyMae Ray....
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Teased by Fire
Molly O'HareFrom USA Today bestselling author Molly O’Hare comes an enemiestolovers, older brother’s best friend, romantic comedy with a curvy, antisocial, supernaturalobsessed, allyearround h...
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The Odyssey
HomerAn Apple Books Classic edition. Homer’s eighthcentury epic poem is a companion to The Iliad . It tells the story of Odysseus, who journeys by ship for 10 years after the Trojan War...
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Tempting the King
Jessa YorkAn escaped Mafia Queen, hiding from her past. A Mafia King who wants to claim her… Giselle They think I'm lostbut I know better. I can never be found. The path I've creat...
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The Three Little Pigs
Mark LeskyClassic fairy tales, legends and folk stories in short version without violence retold with lovely illustrations in simple language. Perfect for reading aloud to small chi...
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Silenced Girls
Roger Stelljes“ Wow wow wow!  Grips you in a choke hold and  does not let go … Oozes suspense and  bonechilling twists and turns .  Astonishing … One of those...
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Think and Grow Rich
Greg Habstritt & Napoleon HillThink and Grow Rich is one of the most popular success book of alltime, having sold more than 60 million copies since it was first published more than 70...
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Never Enough
Lexy TimmsBe good enough never is... Anthony Accardi is a man on a mission: make his father's watch company a success while bringing in millions of dollars. To do that, he needs an assi...
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Assisting the Bosshole
Kristin MacQueenNo hot water? Check Missed the train? Check Broke my heel? Check Dropped my coffee? Check My first day of my new job can’t possibly go worse, right? Wrong. When I meet Parker Scott...
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Noxious
Lexy TimmsStop setting yourself on fire to keep someone else warm. Brady and Levi have been together since high school, since before he became famous and started thinking only about himself....
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The Art of War
Sun TzuAn Apple Books Classic edition. It’s believed that Sun Tzu wrote this Chinese military primer during the 5th century BChundreds of years before the Bible. The book’s 13 chapters ex...
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Teach Me
Cassandra DeanFrom awardwinning author Cassandra Dean comes a tale where lessons of pleasure between a curious, sunshine widow and a dissolute, grumpy earl leads to passion and allconsuming love...
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His Own Heaven
Jennie KewWinner of the 2021 Passionate Plume Award for BDSM Romance Finalist in the 2021 Stiletto Contest for Contemporary Romance He taught her to trust, she taught him to love. Lucy Bar...
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The Icing on the Cake
Linda SeedShe’s a baker without a kitchen. He’s got a double oven to spare. It’s a recipe for success, until his mother starts stirring up trouble … Cassie Jordan has a sweet dream to open a...
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Awaken Me
Jenna JacobHe was more than a ghost haunting my dreams…he was real. By day, I’m Julianna Garrett …a prim, proper accountant. By night, I’m tormented by dreams of an alpha, ambereyed Adonis wh...
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Silver Santa
Lacey SilksTrapped together on Christmas, their unintended onenight stand becomes a lifechanging encounter amidst the snow. Laura Young's professional role as a security guard at the Sil...
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Hard Love
Peyton BanksHe was football royalty. Legendary quarterback. A champion.  Reiner Strickland had led his team to three national championships and playing a knight in shining armor was a...
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The Great Gatsby
F. Scott FitzgeraldAn Apple Books Classics edition. The Roaring Twenties are in full effect in F. Scott Fitzgerald’s riveting classic. Manabouttown Jay Gatsby seems to have it all, including loads of...
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Dracula
Bram StokerAn Apple Books Classic edition. Few characters have seized readers’ imaginations quite like Count Dracula of Transylvania, the hero of Bram Stoker’s classic. The 1897 novel put vam...
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The Next Girl
Carla KovachIF YOU ONLY READ ONE BOOK THIS YEAR, MAKE IT THE NEXT GIRL... You thought he’d come to save you. You were wrong. ‘ Absolutely the best thriller I’ve read this year! ’ Goodreads Rev...