Muñoz-Darias, T., Casares, J., Mata Sánchez, D. et al. (22 more authors) (2017) Flares, wind and nebulae: the 2015 December mini-outburst of V404 Cygni. Monthly Notices of the Royal Astronomical Society: Letters, 465 (1). L124-L128. ISSN 1745-3925
Abstract
After more than 26 years in quiescence, the black hole transient V404 Cyg went into a luminous outburst in 2015 June, and additional activity was detected in late December of the same year. Here, we present an optical spectroscopic follow-up of the December mini-outburst, together with X-ray, optical and radio monitoring that spanned more than a month. Strong flares with gradually increasing intensity are detected in the three spectral ranges during the ∼10 d following the Swift trigger. Our optical spectra reveal the presence of a fast outflowing wind, as implied by the detection of a P-Cyg profile (He I–5876 Å) with a terminal velocity of ∼2500 km s−1 . Nebular-like spectra – with an Hα equivalent width of ∼500 Å – are also observed. All these features are similar to those seen during the main 2015 June outburst. Thus, the fast optical wind simultaneous with the radio jet is most likely present in every V404 Cyg outburst. Finally, we report on the detection of a strong radio flare in late 2016 January, when X-ray and optical monitoring had stopped due to Sun constraints.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society: Letters ©: 2016 Author(s). Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved. |
Keywords: | accretion; accretion discs – stars: individual: V404 Cygni – X-rays: binaries |
Dates: |
|
Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > Department of Physics and Astronomy (Sheffield) |
Funding Information: | Funder Grant number SCIENCE AND TECHNOLOGY FACILITIES COUNCIL ST/M001350/1 SCIENCE AND TECHNOLOGY FACILITIES COUNCIL ST/P001076/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 02 Feb 2017 16:35 |
Last Modified: | 12 Apr 2017 11:43 |
Published Version: | http://doi.org/10.1093/mnrasl/slw222 |
Status: | Published |
Publisher: | Oxford University Press |
Refereed: | Yes |
Identification Number: | 10.1093/mnrasl/slw222 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:107613 |