Rapid multiwavelength variability reveals jet emission in the black hole binary V404 Cygni in quiescence

Borowski, Eric; Hynes, Robert; Tetarenko, Alexandra; Plotkin, Richard; Shahbaz, Tariq; Charles, Philip; Gandhi, Poshak; Heinke, Craig; Maccarone, Thomas; Miller-Jones, James; Russell, Thomas; Shaw, Aarran; Sivakoff, Gregory
Bibliographical reference

AAS/High Energy Astrophysics Division

Advertised on:
5
2024
Number of authors
13
IAC number of authors
1
Citations
0
Refereed citations
0
Description
Spitzer Space Telescope observations of several quiescent black hole low mass X-ray binaries (LMXBs) have shown mid-infrared excesses above the emission of a companion star. The excess has been proposed to originate from either a relativistic jet or circumbinary disk. If the mid-IR originates in a jet, then it probes the region closest to the black hole. Alternatively, the existence of a circumbinary disk would have profound implications for binary angular momentum evolution. We present the results of multiwavelength time series observations of one such LMXB in quiescence, V404 Cyg, from JWST, ALMA, VLA, GTC/HiPERCAM, Chandra X-ray Observatory, XMM-Newton, and Skinakas Observatory. These observations were undertaken in order to discriminate between the two interpretations of the mid-IR excess and probe the properties of the putative jet. We show that the large variability on short timescales observed in the IR by JWST and simultaneously by other facilities confirms that the excess observed by Spitzer in V404 Cyg is dominated by synchrotron radiation from the inner jet and not thermal reprocessing in a circumbinary disk. The variability timescales indicate that the mid-IR emission region must be at least an order of magnitude smaller than the accretion disk. We acknowledge support from a Graduate Student Research Assistance award from the Louisiana Space Consortium. Support for JWST program #3384 was provided by NASA through a grant from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-03127.