Direct evidence for shock-powered optical emission in a nova

Article

Direct evidence for shock-powered optical emission in a nova

Aydi, E.; Sokolovsky, K. V.; Chomiuk, L.; Steinberg, E.; Li, K.-L.; Vurm, I.; Metzger, B. D.; Strader, J.; Mukai, K.; Pejcha, O.; Shen, K. J.; Wade, G. A.; Kuschnig, R.; Moffat, A. F. J.; Pablo, H.; Pigulski, A.; Popowicz, A.; Weiss, W.; Zwintz, K.; Izzo, L. P.; Karen R.; Handler, G.; Ryder, S. D.; Filipovic, M. D.; Alsaberi, R. Z. E.; Manojlovic, P.; Lopes de Oliveira, R.; Walter, F. M.; Vallely, P. J.; Buckley, D. A. H.; Brown, M. J. I.; Harvey, E. J.; Kawash, A.; Kniazev, A.; Kochanek, C. S.; Linford, J.; Mikolajewska, .; Molaro, P.; Orio, M.; Page, K. L.; Shappee, B. J.; Sokoloski, J. L.

Nat. Astron. 4, 776-780 (2020)

doi ↗ arXiv:2004.05562 ↗

Abstract

Classical novae are thermonuclear explosions that occur on the surfaces of white dwarf stars in interacting binary systems1. It has long been thought that the luminosity of classical novae is powered by continued nuclear burning on the surface of the white dwarf after the initial runaway2. However, recent observations of gigaelectronvolt ?-rays from classical novae have hinted that shocks internal to the nova ejecta may dominate the nova emission. Shocks have also been suggested to power the luminosity of events as diverse as stellar mergers3, supernovae4 and tidal disruption events5, but observational confirmation has been lacking. Here we report simultaneous space-based optical and ?-ray observations of the 2018 nova V906 Carinae (ASASSN-18fv), revealing a remarkable series of distinct correlated flares in both bands. The optical and ?-ray flares occur simultaneously, implying a common origin in shocks. During the flares, the nova luminosity doubles, implying that the bulk of the luminosity is shock powered. Furthermore, we detect concurrent but weak X-ray emission from deeply embedded shocks, confirming that the shock power does not appear in the X-ray band and supporting its emergence at longer wavelengths. Our data, spanning the spectrum from radio to ?-ray, provide direct evidence that shocks can power substantial luminosity in classical novae and other optical transients.

Institute authors

Pejcha, Ondřej

Supported by

ERC 803158 — Cat-In-hAT: Catastrophic Interactions of Binary Stars and the Associated Transients, Horizon 2020 ERC Starting Grant 803158
MSMT LTAUSA18093 — Časová proměnnost v astronomii: účast v projektu All-Sky Automated Survey for Supernovae

BibTeX

@article{UTF816,
  author        = {Aydi, E. and Sokolovsky, K. V. and Chomiuk, L. and Steinberg, E. and Li, K.-L. and Vurm, I. and Metzger, B. D. and Strader, J. and Mukai, K. and Pejcha, O. and Shen, K. J. and Wade, G. A. and Kuschnig, R. and Moffat, A. F. J. and Pablo, H. and Pigulski, A. and Popowicz, A. and Weiss, W. and Zwintz, K. and Izzo, L. P. and Karen R. and Handler, G. and Ryder, S. D. and Filipovic, M. D. and Alsaberi, R. Z. E. and Manojlovic, P. and Lopes de Oliveira, R. and Walter, F. M. and Vallely, P. J. and Buckley, D. A. H. and Brown, M. J. I. and Harvey, E. J. and Kawash, A. and Kniazev, A. and Kochanek, C. S. and Linford, J. and Mikolajewska, . and Molaro, P. and Orio, M. and Page, K. L. and Shappee, B. J. and Sokoloski, J. L.},
  title         = {{Direct evidence for shock-powered optical emission in a nova}},
  journal       = {Nat. Astron.},
  volume        = {4},
  pages         = {776-780},
  year          = {2020},
  doi           = {10.1038/s41550-020-1070-y},
  eprint        = {2004.05562},
  archivePrefix = {arXiv},
}