Gas phase SiO in the circumstellar environment of the recurrent nova T Coronae Borealis

A. Evans, Ya V. Pavlenko, D. P.K. Banerjee, U. Munari, R. D. Gehrz, C. E. Woodward, S. Starrfield, L. A. Helton, M. Shahbandeh, S. Davis, S. Dallaporta, G. Cherini

Research output: Contribution to journalArticle

Abstract

We report the discovery of the diatomic molecule SiO in the gas phase in the environment of the recurrent nova T Coronae Borealis. While some of the SiO is photospheric, a substantial portion must arise in the wind from the red giant component of T CrB. A simple fit to the SiO feature, assuming local thermodynamic equilibrium, suggests a SiO column density of 2.8 × 1017 cm-2 and temperature ∼1000 K; the SiO column density is similar to that present in the winds of field red giants. A search for SiO maser emission is encouraged both before and after the next anticipated eruption. We find that the 12C/13C ratio in the red giant is <9, with a best-fitting value of ∼5, a factor ∼18 times lower than the solar value of 89. We find no convincing evidence for the presence of dust in the environment of T CrB, which we attribute to the destructive effects on nucleation sites of hard X-ray emission. When the next eruption of T CrB occurs, the ejected material will shock the wind, producing X-ray and coronal line emission, as is the case for the recurrent nova RS Oph. T CrB is also a good candidate for very high energy γ-ray emission, as first observed during the 2010 outburst of V407 Cyg. We include in the paper a wide variety of infrared spectroscopic and photometric data.

Original languageEnglish (US)
Pages (from-to)3498-3505
Number of pages8
JournalMonthly Notices of the Royal Astronomical Society
Volume486
Issue number3
DOIs
StatePublished - Jan 1 2019

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Keywords

  • circumstellar matter
  • infrared: stars
  • novae, cataclysmic variables
  • stars: AGB and post-AGB
  • stars: individual: T CrB

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science

Cite this

Evans, A., Pavlenko, Y. V., Banerjee, D. P. K., Munari, U., Gehrz, R. D., Woodward, C. E., Starrfield, S., Helton, L. A., Shahbandeh, M., Davis, S., Dallaporta, S., & Cherini, G. (2019). Gas phase SiO in the circumstellar environment of the recurrent nova T Coronae Borealis. Monthly Notices of the Royal Astronomical Society, 486(3), 3498-3505. https://doi.org/10.1093/mnras/stz1071