Constraints on the Progenitor System of the Type Ia Supernova SN 2011fe/PTF11kly by Li, W, Bloom, J, Podsiadlowski, P, Miller, A, Cenko, S, Jha, S, Sullivan, M, Howell, D, Nugent, P, Butler, N, Ofek, E, Kasliwal, M, Richards, J, Stockton, A, Shih, H, Bildsten, L, Shara, M, Bibby, J, Filippenko, A, Ganeshalingam, M, Silverman, J, Kulkarni, SR, Law, N, Poznanski, D, Quimby, R

“…General consensus holds that Type Ia SNe result from thermonuclear explosions of a white dwarf (WD) in a binary system; however, little is known of the precise nature of the companion star and the physical properties of the progenitor system. …”

G 68-34: A Double-lined M-dwarf Eclipsing Binary in a Hierarchical Triple System by Emily K. Pass, David Charbonneau

“…The pair also has a white-dwarf primary at 9″ separation, with the system known to be older than 5 Gyr from the white-dwarf cooling age. …”
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MHD Modeling of Mass Transfer Processes in Close Binary Stars by Andrey Zhilkin, Andrey Sobolev, Dmitry Bisikalo

“…In such systems, instead of an accretion disk, a collimated stream of matter is formed, moving along the magnetic field lines to the magnetic poles of the white dwarf. It is shown that in synchronous polars, variations of the mass transfer rate lead to a change in the spatial configuration of the flow. …”
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THE PAST AND FUTURE HISTORY OF REGULUS by Podsiadlowski, Ph., Horev, I., Rappaport, Saul A

“…We show how the recent discovery of a likely close white dwarf companion to the well-known star Regulus, one of the brightest stars in the sky, leads to considerable insight into the prior evolutionary history of this star, including the cause of its current rapid rotation. …”
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DISCOVERY OF A CANDIDATE FOR THE COOLEST KNOWN BROWN DWARF by Luhman, K. L., Bochanski, John J., Burgasser, Adam J.

“…Through this work, we have discovered a faint companion to the white dwarf WD 0806-661. The comoving source has a projected separation of 130'', corresponding to 2500 AU at the distance of the primary (19.2 pc). …”
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The Vertical Structure of Accretion Disks for Dwarf Novae by Kyu Hong Choi, Kyung Mee Kim

“…The mass and the radius of white dwarf were taken as 1 Msolar and 10^9 cm, respectively. …”
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Orbital Decay in an Accreting and Eclipsing 13.7 Minute Orbital Period Binary with a Luminous Donor by Kevin B. Burdge, Kareem El-Badry, Saul Rappaport, Tin Long Sunny Wong, Evan B. Bauer, Lars Bildsten, Ilaria Caiazzo, Deepto Chakrabarty, Emma Chickles, Matthew J. Graham, Erin Kara, S. R. Kulkarni, Thomas R. Marsh, Melania Nynka, Thomas A. Prince, Robert A. Simcoe, Jan van Roestel, Zach Vanderbosch, Eric C. Bellm, Richard G. Dekany, Andrew J. Drake, George Helou, Frank J. Masci, Jennifer Milburn, Reed Riddle, Ben Rusholme, Roger Smith

“…The system contains a white dwarf accretor, which likely originated as a post–common envelope carbon–oxygen (CO) white dwarf, and a warm donor ( T _eff,donor = 16,400 ± 1000 K). …”
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Equation of state for entanglement in a Fermi gas by Lunkes, C, Brukner, C, Vedral, V

“…We relate entanglement distance to degeneracy pressure both for extreme relativistic and nonrelativistic systems, and estimate the entanglement distance in a white dwarf. Treating entanglement as a thermodynamical quantity, we relate the entropy of formation and concurrence to relative electron distance, pressure, and temperature, to form an equation of state for entanglement. © 2005 The American Physical Society.…”

A Multiwavelength Light-curve Model of the Classical Nova V339 Del: A Mechanism for the Coexistence of Dust Dip and Supersoft X-Rays by Izumi Hachisu, Mariko Kato, Katsura Matsumoto

“…However, the optical depth of the dust shell is too small to absorb the photospheric (X-ray) emission of the white dwarf. This is the reason that a dust shell and soft X-ray radiation coexist. …”
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Multiwavelength Transit Observations of the Candidate Disintegrating Planetesimals Orbiting WD 1145+017 by Croll, Bryce, Dalba, Paul A., Vanderburg, Andrew, Eastman, Jason, DeVore, John, Bieryla, Allyson, Muirhead, Philip S., Han, Eunkyu, Latham, David W., Beatty, Thomas G., Wittenmyer, Robert A., Wright, Jason T., Johnson, John Asher, McCrady, Nate, Rappaport, Saul A

“…We present multiwavelength, ground-based follow-up photometry of the white dwarf WD 1145+017, which has recently been suggested to be orbited by up to six or more short-period, low-mass, disintegrating planetesimals. …”
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Continuing activity in the old novae HR Del and RR Pic by Friedjung, M, Selvelli, P

“…The question arises whether these novae have maintained a form of activity possibly involving a low level of nuclear burning on a low mass white dwarf for many decades after the outburst.…”

Nova outbursts and the CV mass transfer rate spectrum by Kolb, U

“…I present an analytical model and show that the effect is negligible below the period gap and for CVs with high-mass white dwarfs. If the orbital period is longer than 3 hr, the mass transfer rate spectrum has an effective width in excess of an order of magnitude provided the mass accreted on the white dwarf prior to the runaway is in excess of a few 10(-4) M..…”

Progenitor's signatures in type Ia supernova remnants by Chiotellis, A, Kosenko, D, Schure, K, Vink, J

“…We find that Kepler's SNR is consistent with a symbiotic binary progenitor consisting of a white dwarf and an AGB star. Our hydrosimulations can reproduce the observed kinematic and morphological properties. …”

The Carbon Star DY Persei May Be a Cool R Coronae Borealis Variable by D. A. García-Hernández, N. Kameswara Rao, David L. Lambert, K. Eriksson, A. B. S. Reddy, Thomas Masseron

“…Current opinion considers RCB variables to result from the merger of a He onto a CO white dwarf; observed abundances of these H-deficient stars including the exceptionally low ^16 O/ ^18 O ratios are in fair accord with predicted compositions for white dwarf merger products. …”
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UOCS. XIII. Study of the Far-ultraviolet Bright Stars in the Open Cluster NGC 2420 Using AstroSat by R. K. S. Yadav, Arvind K. Dattatrey, Geeta Rangwal, Annapurni Subramaniam, D. Bisht, Ram Sagar

“…Star 527 is a binary system of a BSS and an extremely low-mass (ELM) white dwarf, while star 646 is a binary system of a horizontal branch star and an ELM white dwarf. …”
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The convective Urca process by Lesaffre, P, Podsiadlowski, P, Tout, C

“…We apply this formalism to convective Urca cores in massive white dwarfs. We stress that in degenerate matter, nuclear reactions that change the number of electrons strongly influence the convective velocities. …”

High-speed Keck spectroscopy of flares and oscillations in AE Aquarii by Skidmore, W, O'Brien, K, Horne, K, Gomer, R, Oke, J, Pearson, K

“…The characteristics of the 33-s oscillations are investigated: we derive the oscillation amplitude spectrum, and from that determine the spectrum of the heated regions on the rotating white dwarf. Blackbody fits to the major and minor pulse spectra and an analysis of the emission-line oscillation properties highlight the shortfalls in the simple hotspot model for the oscillations.…”

Hγ Line Spectrum of Intermediate Polars by Yonggi Kim

“…Kim & Beuermann (1995, 1996) have developed a model for the propagation of X-rays from the accreting white dwarf through the infalling material and the re-emission of the energy deposited by photo-absorption in the optical (and UV) spectral range. …”
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Testing common-envelope binary evolution with measurements of the C-12/C-13 isotopic ratios by Catalan, MS, Smalley, B, Exter, K, Wood, J, Sarna, M

“…We carried out medium resolution spectroscopy of close, detached white dwarf - red dwarf binaries without planetary nebulae and cataclysmic variables in the infra-red K-band (2.3 - 2.4 mum). …”

PTF 11kx: a type Ia supernova with a symbiotic nova progenitor. by Dilday, B, Howell, D, Cenko, S, Silverman, J, Nugent, P, Sullivan, M, Ben-Ami, S, Bildsten, L, Bolte, M, Endl, M, Filippenko, A, Gnat, O, Horesh, A, Hsiao, E, Kasliwal, M, Kirkman, D, Maguire, K, Marcy, G, Moore, K, Pan, Y, Parrent, J, Podsiadlowski, P, Quimby, R, Sternberg, A, Suzuki, N

“…There is a consensus that type Ia supernovae (SNe Ia) arise from the thermonuclear explosion of white dwarf stars that accrete matter from a binary companion. …”