Shock-driven synchrotron radio emission from the 2021 outburst of RS Ophiuchi

Nayana, AJ and Anupama, GC and Roy, N and Banerjee, DPK and Singh, KP and Sonith, LS and Kamath, US (2024) Shock-driven synchrotron radio emission from the 2021 outburst of RS Ophiuchi. In: Monthly Notices of the Royal Astronomical Society, 528 (4). pp. 5528-5536.

PDF mon_not_roy_ast_soc_528_4_2024 (2).pdf - Published Version Restricted to Registered users only Download (1MB)

Abstract

We present low-frequency radio observations of the Galactic symbiotic recurrent nova RS Ophiuchi during its 2021 outburst. The observations were carried out with the upgraded Giant Metrewave Radio Telescope spanning a frequency range of 0.15�1.4 GHz during 23�287 d post the outburst. The average value of the optically thin spectral index is α � �0.4 (Fν � να), indicating a non-thermal origin of the radio emission at the observed frequencies. The radio light curves are best represented by shock-driven synchrotron emission, initially absorbed by a clumpy ionized circumbinary medium. We estimate the mass-loss rate of the red giant companion star to be M � 7.5 � 10�8 M yr�1 for an assumed stellar wind velocity of 20 km s�1. The 0.15�1.4 GHz radio light curves of the 2021 outburst are systematically brighter than those of the 2006 outburst. Considering similar shock properties between the two outbursts, this is indicative of a relatively higher particle number density in the synchrotron emitting plasma in the current outburst. © The Author(s) 2024.

Item Type:	Journal Article
Publication:	Monthly Notices of the Royal Astronomical Society
Publisher:	Oxford University Press
Additional Information:	The copyright for this article belongs to the Oxford University Press.
Keywords:	Giant stars; Synchrotrons, Frequency ranges; Giant metrewave radio telescopes; Light curves; Lower frequencies; Radiation mechanisms: nonthermal; Radio continuum: general; Radio emission; Radio observation; Symbiotics; Transient: nova, Synchrotron radiation
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	22 Apr 2024 10:18
Last Modified:	22 Apr 2024 10:18
URI:	https://eprints.iisc.ac.in/id/eprint/84662

Actions (login required)

View Item