Download or read book White Dwarf Luminosity Functions from Sloan Digital Sky Survey Spectra written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Lettre l diteur de l Almanach des Muses written by and published by . This book was released on 1770 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book A Hot White Dwarf Luminosity Function from the Sloan Digital Sky Survey written by Jurek Krzesiński and published by . This book was released on 2009 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: Aims. We present a hot white dwarf (WD) luminosity function (LF) using data taken from the Sloan Digital Sky Survey (SDSS) Data Release 4. We present and discuss a combined LF, along with separate DA and non-DA as LFs. We explore the completeness of our LFs and interpret a sudden drop in the non-DA LF near 2 M-bol as a transition of the non-DA WD atmosphere into the DA one during WD evolution. Our LF extends roughly between -0.5 M-bol 7 or equivalently, [around] 120 000 K T-eff '25 000 K. Our LF should now be useful for estimates of recent star formation and for studies of neutrino and other potential particle emission losses in hot WDs. Methods: To create a sample whose completeness can be characterized fully, we used stars whose spectra were obtained via the SDSS's 'hot standard' target selection criteria. The hot standard stars were purposefully targeted to a high level of completeness by the SDSS for calibration purposes. We are fortunate that many of them are hot white dwarfs stars. We further limited the sample to stars with fitted temperatures exceeding 23 500 K and log(g)> 7.0. We determined stellar distances for our sample based on their absolute SDSS g filter magnitudes, derived from WD stellar atmosphere model fits to the SDSS stellar spectra. Results: We compared our LF with those of other researchers where overlap occurs; however, our LFs are unique in their extension to the most luminous/hottest WDs. The cool end of our LF connects with the hot end of previously determined SDSS WD LFs and agreement here is quite good. It is also good with previous non-SDSS WD LFs. We note distinct differences between the DA and non-DA LFs and discuss the reliability of the DA LF at its hot end. We have extended the range of luminosities covered in the most recent WD LFs. The SDSS sample is understood quite well and its exploration should contribute to a number of new insights into early white dwarf evolution.
Download or read book White Dwarfs written by Domitilla de Martino and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 443 pages. Available in PDF, EPUB and Kindle. Book excerpt: Proceedings of the NATO Advanced Research Workshop, held in Naples, Italy, 24-28 June 2002
Download or read book White Dwarfs written by Evry L. Schatzman and published by Springer Science & Business Media. This book was released on 1991 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt: 1-Pre-White Dwarf Evolution and White Dwarf Cooling.- New pre-white dwarf evolutionary tracks.- Influence of the phase diagram in the cooling of white dwarfs.- PG1159 stars and the PNN-white dwarf connection.- Analysis of the soft X-ray data from the central star of NGC 7293.- Planetary Nebulae Nuclei with white dwarf spectra.- Atmospheric parameters of subluminous B stars.- White dwarf space densities and birth rates reconsidered.- A spectroscopic determination of the mass distribution of DA white dwarfs.- The age and formation of the Galaxy: clues from the white dwarf luminosity function.- Early results from the ROSAT Wide Field Camera.- The stellar component of the Hamburg Schmidt Survey.- White dwarfs in the Hamburg Schmidt Survey.- 2-Asteroseismology of White Dwarfs.- Asteroseismology of white dwarf stars with the Whole Earth Telescope.- A measurement of the evolutionary timescale of the cool white dwarf G117-B15A with WET.- On the interpretation of the dP/dt measurement in G117-B15A.- The boundaries of the ZZ Ceti instability strip.- Long term variations in ZZ Cetis: G191-16 and HL Tau 76.- Predicting the white dwarf light curves.- A wavelet analysis of the ZZ Ceti star G191 16.- An adiabatic survey for ZZ Ceti stars based on a finite element code.- A study of period change rates in post-AGB stars I. PG 1159-035.- Nonadiabatic nonradial pulsations for DAV white dwarf stars.- 3-Atmospheres and Envelopes.- NLTE Analysis of four PG1159 stars.- A search for trace amounts of hydrogen in DB stars.- Abundances of trace heavy elements in hot DA white dwarfs.- New results on radiative forces on iron in hot white dwarfs.- The effective temperature of the DBV's, and the sensitivity of DB model atmospheres to input physics.- The modified hydrostatic equilibrium equations for stratified high gravity stellar atmospheres.- The DBAQ G35-26.- LP 790-29: preliminary model atmospheres for this strongly polarized carbon white dwarf.- Some effect of the UV radiation from white dwarfs on the accretion of interstellar hydrogen.- Convection in white dwarfs: application of CM theory to helium envelope WDs.- Abundances in cool DZA and DAZ white dwarfs: new results using laboratory damping constants.- Evidence for fractionated accretion of metals on cool white dwarfs.- A new look at old friends: 40 Eri B and GD 323.- The Lyman Alpha line wing in hydrogen-rich white dwarf atmospheres.- Atmospheric parameters for DA white dwarfs in the vicinity of the ZZ Ceti instability strip.- Space Telescope observations of white dwarf stars.- 4-White Dwarfs in Binaries.- A deep spectroscopic survey of white dwarfs in common proper motion binaries.- Double degenerate common proper motion binaries.- Close binary white dwarfs.- New results on cataclysmic variable white dwarfs.- Whole Earth Telescope observations of the interacting white dwarf binary system AM CVn: first results.- IUE observations of V803 Cen in high and low states.- Whole Earth Telescope observations of PG1346+082.- On the origin of LMXRBS: the ONEMG case.
Download or read book White Dwarfs From the SDSS 90 Prime Goin Deep in the White Dwarf Luminosity Function written by and published by . This book was released on 2006 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: A large sample of cool white dwarfs from the Sloan Digital Sky Survey has been used to construct a luminosity function (LF), with the selection based on the method of reduced proper motion. While the sample is 60 times larger than that from our Luyten Half Second proper motion survey, its sensitivity to the region past the peak of the LF is severely limited by the necessity to match positions with detections from Palomar plates. A new survey to realize the full limiting magnitudes of the SDSS is described.
Download or read book 15th European Workshop on White Dwarfs written by Ralf Napiwotzki and published by . This book was released on 2007 with total page 718 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book White Dwarfs Advances in Observation and Theory written by M.A. Barstow and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 555 pages. Available in PDF, EPUB and Kindle. Book excerpt: The European Workshop on White Dwarfs was initiated by Prof. V. Weidemann, with the first meeting held in Kiel (FRG) in 1974. Since then a similar workshop has been held almost every two years: Frascati (1976), Tel Aviv (1978), Paris (1981), Kiel (1984), Frascati (1986) and Toulouse (1990). Two major IAU colloquia have also been devoted to the study of white dwarfs (No. 53, Rochester NY, 1979; No. 114, Hanover, NH, 1988). Our most recent meeting, the 8th Workshop, marks a number of important advances in both observational and theoretical studies of white dwarfs. This coincides with a significant expansion in the size of the community active in the field, as was clear from an increase in the number of participants between this workshop (77) and that in Toulouse (46), just two years ago. Key parts of any workshop are the discussion sessions following the pa pers. However, these are difficult to record and, very often, the 'live' flavour of the debates is lost. During this workshop we carried out an experiment, recording the discussion sessions on video tape and then transcribing these later for the proceedings. Although the recordings were made in non-studio conditions with regard to lighting and noise, only a very small part was unin telligible. All participants were given an opportunity to check their questions and answers for scientific accuracy and to correct any errors arising in the transcription process.
Download or read book White Dwarfs Cosmological and Galactic Probes written by E. Sion and published by Springer Science & Business Media. This book was released on 2005-08-25 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt: The emphasis on white dwarf stars and cosmology arises from the most recent advances in cosmological and galactic structure research in which white dwarf stars are playing a very prominent role. Examples are Type Ia supernovae (i.e. white dwarf supernovae), the origin and evolution of the universe, the age of the galactic disk, cosmochronology using white dwarfs in globular clusters and galactic clusters, and the physics of accretion onto compact (very dense) stars. As an assisting guide to the reader, we have included, by invitation, comprehensive review articles in each of the four major areas of the book, white dwarf supernovae, cosmology, accretion physics and galactic structure. The reviews include introductory material that they build upon. The book is suitable and most useful to advanced undergraduates, graduate students and scientific professionals (e.g. astronomers, astrophysicists, cosmologists, physicists).
Download or read book The Luminosity Function for White Dwarfs in the SuperCOSMOS Sky Survey written by Nicholas Rowell and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book White Dwarf Atmospheres and Circumstellar Environments written by Donald W. Hoard and published by John Wiley & Sons. This book was released on 2012-09-19 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by selected astronomers at the forefront of their fields, this timely and novel book compiles the latest results from research on white dwarf stars, complementing existing literature by focusing on fascinating new developments in our understanding of the atmospheric and circumstellar environments of these stellar remnants. Complete with a thorough refresher on the observational characteristics and physical basis for white dwarf classification, this is a must-have resource for researchers interested in the late stages of stellar evolution, circumstellar dust and nebulae, and the future of our own Solar System.
Download or read book Luminosity Functions and Galaxy Bias in the Sloan Digital Sky Survey written by James G. Cresswell and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 14th European Workshop on White Dwarfs written by Detlev Koester and published by . This book was released on 2005 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Luminosity Function for White Dwarfs in the SuperCOSMOS Sky Survey written by Nicholas Robertson Rowell and published by . This book was released on 2010 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Recueil factice d articles de presse concernant Heinrich Sch tz et Kurt Spanich written by and published by . This book was released on with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectrophotometric Investigations of White Dwarf Stars written by James W. Liebert and published by . This book was released on 1977 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Astrophysics in a Nutshell written by Dan Maoz and published by Princeton University Press. This book was released on 2016-02-23 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt: The ideal one-semester astrophysics introduction for science undergraduates—now expanded and fully updated Winner of the American Astronomical Society's Chambliss Award, Astrophysics in a Nutshell has become the text of choice in astrophysics courses for science majors at top universities in North America and beyond. In this expanded and fully updated second edition, the book gets even better, with a new chapter on extrasolar planets; a greatly expanded chapter on the interstellar medium; fully updated facts and figures on all subjects, from the observed properties of white dwarfs to the latest results from precision cosmology; and additional instructive problem sets. Throughout, the text features the same focused, concise style and emphasis on physics intuition that have made the book a favorite of students and teachers. Written by Dan Maoz, a leading active researcher, and designed for advanced undergraduate science majors, Astrophysics in a Nutshell is a brief but thorough introduction to the observational data and theoretical concepts underlying modern astronomy. Generously illustrated, it covers the essentials of modern astrophysics, emphasizing the common physical principles that govern astronomical phenomena, and the interplay between theory and observation, while also introducing subjects at the forefront of modern research, including black holes, dark matter, dark energy, and gravitational lensing. In addition to serving as a course textbook, Astrophysics in a Nutshell is an ideal review for a qualifying exam and a handy reference for teachers and researchers. The most concise and current astrophysics textbook for science majors—now expanded and fully updated with the latest research results Contains a broad and well-balanced selection of traditional and current topics Uses simple, short, and clear derivations of physical results Trains students in the essential skills of order-of-magnitude analysis Features a new chapter on extrasolar planets, including discovery techniques Includes new and expanded sections and problems on the physics of shocks, supernova remnants, cosmic-ray acceleration, white dwarf properties, baryon acoustic oscillations, and more Contains instructive problem sets at the end of each chapter Solutions manual (available only to professors)
