255 citations · 329 across the 5 of their papers we have counts for
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A Nearby Old Halo White Dwarf Candidate from the Sloan Digital Sky Survey
Patrick B. Hall, Piotr M. Kowalski, Hugh C. Harris +5
We report the discovery of a nearby, old, halo white dwarf candidate from the Sloan Digital Sky Survey. SDSS J110217.48+411315.4 has a proper motion of 1.75 arcsec/year and redder…
The First Mid-Infrared Spectra of Cool White Dwarfs
Mukremin Kilic, Piotr M. Kowalski, Fergal Mullally +2
We present the first mid-infrared spectra of two cool white dwarfs obtained with the Spitzer Space Telescope. We also present 3.5-8 micron photometry for 19 cool white dwarfs with…
White dwarf atmosphere models with Ly- opacity in the analysis of the white dwarf cooling sequence of NGC 6397
Piotr M. Kowalski
We discuss the importance of pure hydrogen white dwarf atmosphere models with Ly- far red wing opacity in the analysis of the white dwarf cooling sequence of the globular cl…
The Pseudo-continuum Bound-free Opacity of Hydrogen and its Importance in Cool White Dwarf Atmospheres
Piotr M. Kowalski
We investigate the importance of the pseudo-continuum bound-free opacity from hydrogen atoms in the atmospheres of cool white dwarfs. This source of absorption, when calculated by…
On the Dissociation Equilibrium of H2 in Very Cool, Helium-Rich White Dwarf Atmospheres
Piotr M. Kowalski
We investigate the dissociation equilibrium of in very cool, helium-rich white dwarf atmospheres. We present the solution of the non-ideal chemical equilibrium for the di…
Radiative transfer in the refractive atmospheres of very cool white dwarfs
P. M. Kowalski, D. Saumon
We consider the problem of radiative transfer in stellar atmospheres where the index of refraction departs from unity and is a function of density and temperature. We present modif…