中文
相关论文

相关论文: The White Dwarf Luminosity Function from SDSS Imag…

200 篇论文

We present 594 radial velocity measurements for 71 white dwarfs obtained during our search for binary white dwarfs and not reported elsewhere. We identify three excellent candidate binaries, which require further observations to confirm our…

天体物理学 · 物理学 2009-10-31 P. F. L. Maxted , T. R. Marsh , C. K. J. Moran

We present improved atmospheric parameters of nearby white dwarfs lying within 20 pc of the Sun. The aim of the current study is to obtain the best statistical model of the least-biased sample of the white dwarf population. A homogeneous…

太阳与恒星天体物理 · 物理学 2015-06-04 Noemi Giammichele , Pierre Bergeron , Patrick Dufour

Aims: In this work the luminosity function of QSOs is measured in the redshift range 3.5<z<5.2 for the absolute magnitude interval -21<M_{145}<-28. The determination of the faint end of the luminosity function at these redshifts provides…

天体物理学 · 物理学 2009-11-11 F. Fontanot , S. Cristiani , P. Monaco , M. Nonino , E. Vanzella , W. N. Brandt , A. Grazian , J. Mao

Given the importance of white dwarfs (WDs) in many fields of modern astrophysics, the precise knowledge of the actual degree of accuracy of the associated theoretical predictions is a primary task. In the first paper of a series dedicated…

天体物理学 · 物理学 2009-11-13 P. G. Prada Moroni , O. Straniero

Aims: We study single and binary white dwarfs in the inner halo of the Milky Way in order to learn more about the conditions under which the population of halo stars was born, such as the initial mass function (IMF), the star formation…

We have identified 109 White Dwarf (WD) - M dwarf pairs in the Sloan Digital Sky Survey (SDSS) with g < 20th magnitude. For each system we determined the temperature of the WD primary and the spectral type of the M dwarf secondary. Using…

Observed galaxy luminosities (derived from redshifts) hold information on the large-scale peculiar velocity field in the form of spatially correlated scatter, which allows for bounds on bulk flows and the growth rate of matter density…

宇宙学与河外天体物理 · 物理学 2017-04-04 Martin Feix , Enzo Branchini , Adi Nusser

We present the first detailed 3D kinematic analysis of a sample of 3133 white dwarfs that use Gaia astrometry plus radial velocities, which were measured either by Gaia or by ground based spectroscopic observations. The sample includes…

The recent discovery of microlensing of stars in the Large Magellanic Cloud has excited much interest in the nature of the lensing population. Detailed analyses indicate that the mass of these objects ranges from 0.3-0.8 solar masses,…

天体物理学 · 物理学 2007-05-23 Brad M. S. Hansen

We measure luminosity functions in the cores of four spiral-rich, poor clusters of galaxies at median redshift $z = 0.016$. In the red magnitude range -14 < M_R < -10, our data imply that the luminosity functions phi(L) \propto L^{alpha}…

天体物理学 · 物理学 2015-06-24 Neil Trentham

White dwarfs are the remnants of low and intermediate mass stars. Because of electron degeneracy, their evolution is just a simple gravothermal process of cooling. Recently, thanks to Gaia data, it has been possible to construct the…

星系天体物理 · 物理学 2019-06-12 Jordi Isern

A detailed analysis of halo white dwarf candidates is presented, which is based on model atmosphere fits to observed energy distributions built from photoelectric or photographic magnitudes. Most of the candidates identified in reduced…

天体物理学 · 物理学 2009-11-07 P. Bergeron

(Abridged) The Sloan Digital Sky Survey now extends over a large enough region that galaxies in low density environments can be detected. Rojas et al. have developed a technique to extract more than 1000 void galaxies with delta rho/rho <…

天体物理学 · 物理学 2009-11-10 Fiona Hoyle , Randall R. Rojas , Michael S. Vogeley , John Brinkmann

White dwarfs are one of the few types of stellar objects for which we know almost nothing about the possible existence of companion planets. Recent evidence for metal contaminated atmospheres, circumstellar debris disks and transiting…

地球与行星天体物理 · 物理学 2019-05-15 Jorge Cortes , David M. Kipping

The white dwarf luminosity function, which provides information about their cooling, has been measured with high precision in the past few years. Simulations that include well known Standard Model physics give a good fit to the data. This…

高能物理 - 唯象学 · 物理学 2015-06-15 Herbert K. Dreiner , Jean-François Fortin , Jordi Isern , Lorenzo Ubaldi

White dwarf (WD) stars evolve simply and predictably, making them reliable age indicators. However, self-consistent validation of the methods for determining WD total ages has yet to be widely performed. This work uses 1565 wide ( > 100 au)…

太阳与恒星天体物理 · 物理学 2022-08-17 Tyler M. Heintz , J. J. Hermes , Kareem El-Badry , Charlie Walsh , Jennifer L. van Saders , C. E. Fields , Detlev Koester

We present a follow-up analysis of the unique magnetic luminosity-variable carbon-atmosphere white dwarf SDSS J142625.71+575218.3. This includes the results of some 106.4 h of integrated light photometry which have revealed, among other…

太阳与恒星天体物理 · 物理学 2009-09-28 E. M. Green , P. Dufour , G. Fontaine , P. Brassard

We present the bivariate brightness distribution (BBD) for the 2dF Galaxy Redshift Survey (2dFGRS) based on a preliminary subsample of 45,000 galaxies. The BBD is an extension of the galaxy luminosity function incorporating surface…

Recent results of microlensing surveys, show that 10-20% of the dark halo mass of the Milky Way consists of compact objects. The masses of these compact objects range from 0.1 to 1 solar mass. New theoretical cooling models for white…

天体物理学 · 物理学 2007-05-23 Jelte de Jong , Konrad Kuijken , Mark Neeser

We perform photometric analyses for a bright early-type galaxy (ETG) sample with 2949 galaxies ($M_{\rm r}<-22.5$ mag) in the redshift range of 0.05 to 0.15, drawn from the SDSS DR7 with morphological classification from Galaxy Zoo 1. We…

宇宙学与河外天体物理 · 物理学 2015-06-15 Y. Q. He , X. Y. Xia , C. N. Hao , Y. P. Jing , S. Mao , Cheng Li
‹ 上一页 1 8 9 10 下一页 ›