ATCA observations of radio flaring emission from GX 339-4 during the current hard-to-soft state transition
ATel #14507; S. Corbel (Universite de Paris), T. Tzioumis (ATNF), T. D. Russell (INAF-Palermo), J. C.A. Miller-Jones (ICRAR - Curtin), E. Tremou (Observatoire de Paris)
on 3 Apr 2021; 08:08 UT
Credential Certification: S. CORBEL (stephane.corbel@cea.fr)
Subjects: Radio, Request for Observations, Black Hole, Transient
Following the reactivation of GX 339-4 early 2021 after a period of quiescence (see e.g. ATel #14336, #14351, #14352), we have been monitoring regularly GX 339-4 in radio with the Australia Telescope Compact Array, located in Narrabri, Australia. Observations are usually conducted at 5.5 GHz and 9.0 GHz with a 2 GHz bandwidth.
GX 339-4 recently left the hard state (ATel #14419, #14490) and the ATCA observed the associated quenching of the compact jets from ~28 mJy down to less than 1 mJy. The transition to the soft state started around 2021, March 28 (ATel #14490) and we report the detection of stronger flaring radio emission starting on March 31 and currently continuing as of April 2 with flux density of up to ~50 mJy.
Given the continuing flaring radio activities, we encourage further multi-wavelength observations to accompany the forthcoming new radio observations.
We thank Jamie Stevens and the staff of the ATCA for prompt scheduling of these observations.
