Near-IR studies of recurrent nova V745 Scorpii during its 2014 outburst

Abstract

The recurrent nova (RN) V745 Scorpii underwent its third known outburst on 2014 February 6. Infrared monitoring of the eruption on an almost daily basis, starting from 1.3d after discovery, shows the emergence of a powerful blast wave generated by the high velocity nova ejecta exceeding 4000 kms${}^{-1}$ plowing into its surrounding environment. The temperature of the shocked gas is raised to a high value exceeding 10${}^8$K immediately after outburst commencement. The energetics of the outburst clearly surpass those of similar symbiotic systems like RS Oph and V407 Cyg which have giant secondaries. The shock does not show a free-expansion stage but rather shows a decelerative Sedov-Taylor phase from the beginning. Such strong shockfronts are known to be sites for $\gamma$ ray generation. V745 Sco is the latest nova, apart from five other known novae, to show $\gamma$ ray emission. It may be an important testbed to resolve the crucial question whether all novae are generically $\gamma$ ray emitters by virtue of having a circumbinary reservoir of material that is shocked by the ejecta rather than $\gamma$ ray generation being restricted to only symbiotic systems with a shocked red giant (RG) wind. The lack of a free-expansion stage favors V745 Sco to have a density enhancement around the white dwarf (WD), above that contributed by a RG wind. Our analysis also suggests that the WD in V745 Sco is very massive and a potential progenitor for a future SN Ia explosion.

To appear in ApJ (Letters)

References in corpus (6)

• Gamma-Ray Emission Concurrent with the Nova in the Symbiotic Binary V407 Cygni
• X-Ray Emitting Blast Wave from the Recurrent Nova RS Ophiuchi
• Supersoft X-ray Light Curve of RS Ophiuchi (2006)
• A near-infrared shock wave in the 2006 outburst of recurrent nova RS Ophiuchi
• The Radio Light Curve of the Gamma-Ray Nova in V407 Cyg: Thermal Emission from the Ionized Symbiotic Envelope, Devoured from Within by the Nova Blast
• Discovery of the first symbiotic star in NGC6822

Cited by in corpus (13)

• M31N 2008-12a - the remarkable recurrent nova in M31: Pan-chromatic observations of the 2015 eruption
• A NuSTAR observation of the fast symbiotic nova V745 Sco in outburst
• Recurrent and symbiotic novae in the OGLE data
• Origin of asymmetries in X-ray emission lines from the blast wave of the 2014 outburst of nova V745 Sco
• Chandra High Energy Transmission Gratings Spectra of V3890 Sgr
• Gas phase SiO in the circumstellar environment of the recurrent nova T Coronae Borealis
• Infrared spectroscopy of the remnant of Nova Sco 2014: a symbiotic star with too little circumstellar matter to decelerate the ejecta
• Early multiwavelength analysis of the recurrent nova V745 Sco
• IR study of nova V2468 Cyg from early decline to the coronal phase
• Infrared spectroscopy of the 2019 eruption of the recurrent nova V3890 Sgr: separation into equatorial and polar winds revealed
• Nova Ophiuchus 2017 as a probe of ${}^{13}$C nucleosynthesis and carbon monoxide formation and destruction in classical novae
• Synchrotron emission from double-peaked radio light curves of the symbiotic recurrent nova V3890 Sagitarii
• Stringent limits on ${}^{28}$SiO maser emission from the recurrent nova T Coronae Borealis