The evolution of luminous red nova at 2017jfs in NGC4470?

A. Pastorello*, T. W. Chen, Y. Z. Cai, A. Morales-Garoffolo, Z. Cano, E. Mason, E. A. Barsukova, S. Benetti, M. Berton, S. Bose, F. Bufano, E. Callis, G. Cannizzaro, R. Cartier, Ping Chen, Subo Dong, S. Dyrbye, N. Elias-Rosa, A. Flörs, M. FraserS. Geier, V. P. Goranskij, D. A. Kann, H. Kuncarayakti, F. Onori, A. Reguitti, T. Reynolds, I. R. Losada, A. Sagués Carracedo, T. Schweyer, S. J. Smartt, A. M. Tatarnikov, A. F. Valeev, C. Vogl, T. Wevers, A. De Ugarte Postigo, L. Izzo, C. Inserra, E. Kankare, K. Maguire, K. W. Smith, B. Stalder, L. Tartaglia, C. C. Thöne, G. Valerin, D. R. Young

*Corresponding author for this work

Research output: Contribution to journalLetterScientificpeer-review

1 Citation (Scopus)
80 Downloads (Pure)

Abstract

We present the results of our photometric and spectroscopic follow-up of the intermediate-luminosity optical transient AT 2017jfs. At peak, the object reaches an absolute magnitude of Mg = -15:46 ± 0:15 mag and a bolometric luminosity of 5:5 × 1041 erg s-1. Its light curve has the doublepeak shape typical of luminous red novae (LRNe), with a narrow first peak bright in the blue bands, while the second peak is longer-lasting and more luminous in the red and near-infrared (NIR) bands. During the first peak, the spectrum shows a blue continuum with narrow emission lines of H and Fe II. During the second peak, the spectrum becomes cooler, resembling that of a K-type star, and the emission lines are replaced by a forest of narrow lines in absorption. About 5 months later, while the optical light curves are characterized by a fast linear decline, the NIR ones show a moderate rebrightening, observed until the transient disappears in solar conjunction. At these late epochs, the spectrum becomes reminiscent of that of M-type stars, with prominent molecular absorption bands. The late-time properties suggest the formation of some dust in the expanding common envelope or an IR echo from foreground pre-existing dust. We propose that the object is a common-envelope transient, possibly the outcome of a merging event in a massive binary, similar to NGC4490-2011OT1.

Original languageEnglish
Article number201935511
JournalAstronomy and Astrophysics
Volume625
DOIs
Publication statusPublished - 1 Jan 2019
MoE publication typeA1 Journal article-refereed

Keywords

  • Binaries: Close
  • Stars: Massive
  • Stars: winds, outflows
  • Supernovae: Individual: AT 2017jfs
  • Supernovae: Individual: NGC440-2011OT1

Fingerprint Dive into the research topics of 'The evolution of luminous red nova at 2017jfs in NGC4470?'. Together they form a unique fingerprint.

Cite this