Shortest recurrence periods of forced Novae

Journal Article · Fri Jun 10 04:00:00 EDT 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/824/1/22· OSTI ID:22869018

Hachisu, Izumi ^[1]; Saio, Hideyuki ^[2]; Kato, Mariko ^[3]

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1. Department of Earth Science and Astronomy, College of Arts and Sciences, University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan)
2. Astronomical Institute, Graduate School of Science, Tohoku University, Sendai 980-8578 (Japan)
3. Department of Astronomy, Keio University, Hiyoshi, Yokohama 223-8521 (Japan)

We revisit hydrogen shell burning on white dwarfs (WDs) with higher mass accretion rates than the stability limit, M-dot {sub stable}, above which hydrogen burning is stable. Novae occur with mass accretion rates below the limit. For an accretion rate > M-dot {sub stable}, a first hydrogen shell flash occurs followed by steady nuclear burning, so the shell burning will not be quenched as long as the WD continuously accretes matter. On the basis of this picture, some persistent supersoft X-ray sources can be explained by binary models with high accretion rates. In some recent studies, however, the claim has been made that no steady hydrogen shell burning exists even for accretion rates > M-dot {sub stable}. We demonstrate that, in such cases, repetitive flashes occurred because mass accretion was artificially controlled. If we stop mass accretion during the outburst, no new nuclear fuel is supplied, so the shell burning will eventually stop. If we resume mass accretion after some time, the next outburst eventually occurs. In this way, we can design the duration of outburst and interpulse time with manipulated mass accretion. We call such a controlled nova a “forced nova.” These forced novae, if they exist, could have much shorter recurrence periods than “natural novae.” We have obtained the shortest recurrence periods for forced novae for various WD masses. Based on the results, we revisit WD masses of some recurrent novae, including T Pyx.

• OSTI ID: 22869018
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 824; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
HYDROGEN
HYDROGEN BURNING
MASS
NOVAE
STABILITY
WHITE DWARF STARS
X RADIATION
X-RAY SOURCES