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Related papers: Comparison of White Dwarf Mass Determinations

200 papers

The mass of the dark matter halo of the Milky Way can be estimated by fitting analytical models to the phase-space distribution of dynamical tracers. We test this approach using realistic mock stellar halos constructed from the Aquarius…

Astrophysics of Galaxies · Physics 2015-10-28 Wenting Wang , Jiaxin Han , Andrew P. Cooper , Shaun Cole , Carlos Frenk , Ben Lowing

Astrometric observations of resolved binaries provide estimates of orbital periods and will eventually lead to measurement of dynamical masses. Only a few very low mass star and brown dwarf masses have been measured to date, and the…

The mass radius relationship of white dwarfs, near the Chandrasekhar Limit, is derived for a toy model of uniform density, using the variational principle. A power law scaling, reminiscent of those found in 2nd order phase transitions, is…

Astrophysics · Physics 2007-05-23 Sayan Chakraborti

We present mid-infrared photometry of 124 white dwarf stars with Spitzer Space Telescope. Objects were observed simultaneously at 4.5 and 8.0um with sensitivities better than 1 mJy. This data can be used to test models of white dwarf…

Recent work has found evidence for a difference in the bias and dark matter halo masses of WISE-selected obscured and unobscured quasars, implying a distinction between these populations beyond random line-of-sight effects. However, the…

Astrophysics of Galaxies · Physics 2017-06-28 Michael A. DiPompeo , Ryan C. Hickox , Sarah Eftekharzadeh , Adam D. Myers

The white dwarf luminosity function is well understood in terms of standard model physics and leaves little room for exotic cooling mechanisms related to the possible existence of new weakly interacting light particles. This puts…

High Energy Physics - Phenomenology · Physics 2015-06-17 Lorenzo Ubaldi

White dwarfs are the dense, burnt-out remnants of the vast majority of stars, condemned to cool over billions of years as they steadily radiate away their residual thermal energy. To first order, their atmosphere is expected to be made…

Solar and Stellar Astrophysics · Physics 2024-05-03 Antoine Bédard

We present a detailed analysis of 108 helium-line (DB) white dwarfs based on model atmosphere fits to high signal-to-noise optical spectroscopy. We derive a mean mass of 0.67 Mo for our sample, with a dispersion of only 0.09 Mo. White…

We estimate black hole masses (M$_{\rm BH}$) for 14 gravitationally lensed quasars using the Balmer lines along with estimates based on MgII and CIV emission lines for four and two of them, respectively. We compare with results obtained for…

Astrophysics of Galaxies · Physics 2023-12-13 A. Melo , V. Motta , J. Mejía-Restrepo , R. J. Assef , N. Godoy , E. Mediavilla , E. Falco , C. S. Kochanek , F. Ávila-Vera , R. Jerez

Leveraging the large sample size of low-resolution spectroscopic surveys to constrain white dwarf stellar structure requires an accurate understanding of the shapes of hydrogen absorption lines, which are pressure broadened by the Stark…

Recent surveys have allowed to derive the white dwarf mass distribution with reasonable accuracy. This distribution shows a noticeable degree of structure that it is often attributed to the evolution of close binaries in general, and to…

Solar and Stellar Astrophysics · Physics 2012-11-12 J. Isern , S. Catalan , E. Garcia-Berro , M. Hernanz

The merger of two carbon-oxygen white dwarfs can lead either to a spectacular transient, stable nuclear burning or a massive, rapidly rotating white dwarf. Simulations of mergers have shown that the outcome strongly depends on whether the…

Solar and Stellar Astrophysics · Physics 2015-06-11 Chenchong Zhu , Philip Chang , Marten van Kerkwijk , James Wadsley

We present new optical spectroscopic observations of U Geminorum obtained during a quiescent stage. We performed a radial velocity analysis of three Balmer emission lines yielding inconsistent results. Assuming that the radial velocity semi…

Solar and Stellar Astrophysics · Physics 2023-03-13 J. Echevarría , S. H. Ramírez , M. Fuentes , L. J. Sánchez , V. Patiño , V. Chavushyan

Pulsation modes have recently been observed in a handful of white dwarf (WD) primaries of cataclysmic variables, allowing an interesting new probe into the structure of accreting WD's. We briefly discuss the seismology of these objects, how…

Astrophysics · Physics 2007-05-23 Phil Arras , Dean Townsley , Lars Bildsten

We use the ESPRESSO spectrograph at the Very Large Telescope to measure velocity shifts and gravitational redshifts of eight bona fide Hyades white dwarfs, with an accuracy better than 1.5 percent. By comparing the gravitational redshift…

Solar and Stellar Astrophysics · Physics 2023-05-03 L. Pasquini , A. F. Pala , M. Salaris , H. G. Ludwig , I. Leao , A. Weiss , J. R. de Medeiros

Using stellar population synthesis techniques, we explore the photometric signatures of white dwarf progenitor dominated galactic halos, in order to constrain the fraction of halo mass that may be locked-up in white dwarf stellar remnants.…

Astrophysics · Physics 2009-11-10 H. -c. Lee , B. K. Gibson , Y. Fenner , C. B. Brook , D. Kawata , A. Renda , J. Holopainen , C. Flynn

The virial masses of ultra-diffuse galaxies (UDGs) have been estimated using the kinematics and abundance of their globular cluster populations, leading to disparate results. Some studies conclude that UDGs reside in massive dark matter…

Astrophysics of Galaxies · Physics 2018-12-05 Chervin F. P. Laporte , Adriano Agnello , Julio F. Navarro

With tens to hundreds of spectra of white dwarfs being taken each night from multi-object spectroscopic surveys, automated spectral classification is essential as part of efficient data processing. In this study, we design a neural network…

Analysis of initial observations from near-infrared sky surveys has shown that the resulting photometric catalogues, combined with far-red optical data, provide an extremely effective method of finding isolated, very low-temperature objects…

White dwarfs that accrete the debris of tidally disrupted asteroids provide the opportunity to measure the bulk composition of the building blocks, or fragments, of exoplanets. This technique has established a diversity in compositions…

Earth and Planetary Astrophysics · Physics 2021-02-15 Mark A. Hollands , Pier-Emmanuel Tremblay , Boris T. Gänsicke , Detlev Koester , Nicola P. Gentile-Fusillo