Light-curve analysis of neon novae

Journal Article · Fri Jan 01 04:00:00 EST 2016 · Astrophysical Journal

DOI:https://doi.org/10.3847/0004-637X/816/1/26· OSTI ID:22882322

Hachisu, Izumi ^[1]; Kato, Mariko ^[2]

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1. Department of Earth Science and Astronomy, College of Arts and Sciences, The University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153-8902 (Japan)
2. Department of Astronomy, Keio University, Hiyoshi, Kouhoku-ku, Yokohama 223-8521 (Japan)

We analyzed light curves of five neon novae, QU Vul, V351 Pup, V382 Vel, V693 CrA, and V1974 Cyg, and determined their white dwarf (WD) masses and distance moduli on the basis of theoretical light curves composed of free–free and photospheric emission. For QU Vul, we obtained a distance of d ∼ 2.4 kpc, reddening of E(B − V) ∼ 0.55, and WD mass of M{sub WD} = 0.82–0.96 M{sub ⊙}. This suggests that an oxygen–neon WD lost a mass of more than ∼0.1 M{sub ⊙} since its birth. For V351 Pup, we obtained d∼5.5 kpc, E(B−V)∼0.45, and M{sub WD}=0.98–1.1 M{sub ⊙}. For V382 Vel, we obtained d∼1.6 kpc, E(B−V)∼0.15, and M{sub WD}=1.13–1.28 M{sub ⊙}. For V693 CrA, we obtained d∼7.1 kpc, E(B−V)∼0.05, and M{sub WD}=1.15–1.25 M{sub ⊙}. For V1974 Cyg, we obtained d∼1.8 kpc, E(B−V)∼0.30, and M{sub WD}=0.95–1.1 M{sub ⊙}. For comparison, we added the carbon–oxygen nova V1668 Cyg to our analysis and obtained d∼5.4 kpc, E(B−V)∼0.30, and M{sub WD}=0.98–1.1 M{sub ⊙}. In QU Vul, photospheric emission contributes 0.4–0.8 mag at most to the optical light curve compared with free–free emission only. In V351 Pup and V1974 Cyg, photospheric emission contributes very little (0.2–0.4 mag at most) to the optical light curve. In V382 Vel and V693 CrA, free–free emission dominates the continuum spectra, and photospheric emission does not contribute to the optical magnitudes. We also discuss the maximum magnitude versus rate of decline relation for these novae based on the universal decline law.

• OSTI ID: 22882322
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 1 Vol. 816; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United Kingdom
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
CARBON
COMPARATIVE EVALUATIONS
EMISSION
MASS
NEON
NOVAE
OXYGEN
SPECTRA
WHITE DWARF STARS