New outburst of GX 339-4 confirmed by Swift/XRT
ATel #15578; Amar Deo Chandra (IISER Kolkata)
on 29 Aug 2022; 20:43 UT
Credential Certification: Amar Deo Chandra (amar.deo.chandra@gmail.com)
Subjects: X-ray, Request for Observations, Binary, Black Hole, Transient
Following the report of a new outburst of GX 339-4 detected by the MAXI/GSC on 2022 August 29 (ATel# 15577), we searched the Swift/XRT archival observations for recent X-ray activity of this source. A gradual increase in the 15-50 keV X-ray flux from Swift/BAT monitoring observations since around 2022 August 23 was reported (ATel# 15577). We detect a faint X-ray source at the known location of GX 339-4 using 1.2 ks Swift/XRT observations performed in Photon Counting (PC) mode on 2022 August 6 (MJD 59797). The estimated count rate during this observation is about 0.1 cts/s. The source is not detected during PC mode observations of the region on 2022 July 30 (MJD 59790). This suggests that the source became active around 2022 August 6.
The source is detected during PC mode observations on 2022 August 13 (MJD 59804, 1.1 ks exposure), 2022 August 20 (MJD 59811, 0.9 ks exposure) and 2022 August 27 (MJD 59818, 0.9 ks exposure) having estimated count rate of about 0.9 cts/s, 1.3 cts/s and 1.8 cts/s respectively. Swift/XRT observations of GX 339-4 indicate gradual brightening of the source during the ongoing outburst.
Follow-up multi-wavelength observations are encouraged.
