The $UBV$ Color Evolution of Classical Novae. III. Time-Stretched Color-Magnitude Diagram of Novae in Outburst

Abstract

We propose a modified color-magnitude diagram for novae in outburst, i.e., $(B-V{)}_0$ versus $(M_V-2.5\log f_{\mathrm{s}})$, where $f_{\mathrm{s}}$ is the timescaling factor of a (target) nova against a comparison (template) nova, $(B-V{)}_0$ is the intrinsic $B-V$ color, and $M_V$ is the absolute $V$ magnitude. We dub it the time-stretched color-magnitude diagram. We carefully reanalyzed 20 novae based on the time-stretching method and revised their extinctions $E(B-V)$, distance moduli in the $V$ band $(m-M{)}_V$, distances $d$, and timescaling factors $f_{\mathrm{s}}$ against the template nova LV Vul. We have found that these 20 nova outburst tracks broadly follow one of the two template tracks, LV Vul/V1668 Cyg or V1500 Cyg/V1974 Cyg group, in the time-stretched color-magnitude diagram. In addition, we estimate the white dwarf masses and $(m-M{)}_V$ of the novae by directly fitting the absolute $V$ model light curves ($M_V$) with observational apparent $V$ magnitudes ($m_V$). A good agreement in the two estimates of $(m-M{)}_V$ confirms the consistency of the time-stretched color-magnitude diagram. Our distance estimates are in good agreement with the results of Gaia Data Release 2.

89 pages including 52 figures, in ApJS, 241, 4 (2019)

References in corpus (14)

• An eclipsing binary distance to the Large Magellanic Cloud accurate to 2 per cent
• A Universal Decline Law of Classical Novae
• A 3D extinction map of the Northern Galactic Plane based on IPHAS photometry
• Supersoft X-ray Light Curve of RS Ophiuchi (2006)
• Mapping the Milky Way bulge at high resolution: the 3D dust extinction, CO, and X factor maps
• Shortest Recurrence Periods of Novae
• Optical and Supersoft X-ray Light Curve Models of Classical Nova V2491 Cygni: A New Clue to the Secondary Maximum
• A Light Curve Analysis of Classical Novae: Free-free Emission vs. Photospheric Emission
• Early spectral evolution of Nova Sgr 2004 (V5114 Sgr)
• Near Infrared Observations of the novae V2491 Cygni and V597 Puppis
• The nature and evolution of Nova Cygni 2006
• The unusual Nova Cygni 2006 (V2362 Cyg)
• SALT observations of southern post-novae
• Optical evolution of Nova Ophiuchi 2007 = V2615 Oph

Cited by in corpus (10)

• A Light Curve Analysis of 32 Recent Galactic Novae --- Distances and White Dwarf Masses
• A strong shock during a nova outburst: an origin of multiple velocity systems in optical spectra and of high-energy emissions
• Physics of nova outbursts: A theoretical model of classical nova outbursts with self-consistent wind mass loss
• A Theory for the Maximum Magnitude versus Rate of Decline (MMRD) Relation of Classical Novae
• The $UBV$ Color Evolution of Classical Novae. IV. Time-Stretched $(U-B{)}_0$-$(M_B-2.5\log f_{\mathrm{s}})$ and $(V-I{)}_0$-$(M_I-2.5\log f_{\mathrm{s}})$ Color-Magnitude Diagrams of Novae in Outburst
• A multiwavelength light curve analysis of the classical nova YZ Ret: An extension of the universal decline law to the nebular phase
• Supersoft X-Ray Phases of Recurrent Novae as an Indicator of their White Dwarf Masses
• ASASSN-16oh: A nova outburst with no mass ejection -- A new type of supersoft X-ray source in old populations
• Morpho-kinematic modeling of the expanding ejecta of the extremely slow nova V1280 Scorpii
• A light curve model of V2491 Cyg: Classical nova outburst on a cool and massive white dwarf