Detection of Very Low-frequency, Quasi-periodic Oscillations in the 2015 Outburst of V404 Cygni
Journal
Date Issued
2017
Author(s)
Huppenkothen, D.
•
Younes, G.
•
Ingram, A.
•
Kouveliotou, C.
•
Göğüș, E.
•
BACHETTI, Matteo
•
Sánchez-Fernández, C.
•
Chenevez, J.
•
Motta, S.
•
van der Klis, M.
•
Granot, J.
•
Gehrels, N.
•
Kuulkers, E.
•
Tomsick, J. A.
•
Walton, D. J.
Abstract
In 2015 June, the black hole X-ray binary (BHXRB) V404 Cygni went into outburst for the first time since 1989. Here, we present a comprehensive search for quasi-periodic oscillations (QPOs) of V404 Cygni during its recent outburst, utilizing data from six instruments on board five different X-ray missions: Swift/XRT, Fermi/GBM, Chandra/ACIS, INTEGRAL’s IBIS/ISGRI and JEM-X, and NuSTAR. We report the detection of a QPO at 18 mHz simultaneously with both Fermi/GBM and Swift/XRT, another example of a rare but slowly growing new class of mHz-QPOs in BHXRBs linked to sources with a high orbital inclination. Additionally, we find a duo of QPOs in a Chandra/ACIS observation at 73 mHz and 1.03 Hz, as well as a QPO at 136 mHz in a single Swift/XRT observation that can be interpreted as standard Type-C QPOs. Aside from the detected QPOs, there is significant structure in the broadband power, with a strong feature observable in the Chandra observations between 0.1 and 1 Hz. We discuss our results in the context of current models for QPO formation.
Volume
834
Issue
1
Start page
90
Issn Identifier
0004-637X
Ads BibCode
2017ApJ...834...90H
Rights
open.access