MAXI J0655-013: Swift localization
ATel #15561; J. A. Kennea (PSU), P. A. Evans (Leicester) and H. Negoro (Nihon U)
on 20 Aug 2022; 19:25 UT
Credential Certification: Jamie A. Kennea (kennea@astro.psu.edu)
Subjects: X-ray, Neutron Star
On August 20th, 2022, Swift took a 1.5ks observation of MAXI J0655-013, a transient discovered by MAXI on June 18th, 2022 (ATEL #15442) and which triggered Swift/BAT also on that day (ATEL #15443). Unfortunately at the time of the BAT trigger, MAXI J0655-013 was too close to the Sun to observe, until the observation reported on here. We find a X-ray point source inside the BAT error circle at the following location: RA/Dec(J2000) = 103.80155, -1.48130 which is equivalent to:
Dec(J2000) =06h 55m 12.37s,
RA(J2000) = 01d 28m 52.7s,
with an error radius 2.5 arc-seconds (90% confidence). This position is 1.3 arc-seconds from the star V520 Mon, which is suggested as the optical counterpart of this source based on a NuSTAR localization (ATEL #15495). There are no other X-ray point sources in the field, and this position is consistent with being 3 arc-minutes from the BAT position, very slightly outside the standard 3 arc-minute. This object has been previously detected by Swift (2SXPS J065512.4-012855) on May 23rd, 2018 at a count rate of 0.04 +/- 0.01 c/s. In the recent observation, the source was 0.10 +/- 0.01 c/s, 2.7 times brighter.
We therefore suggest that this observation confirms that MAXI J0655-013 is V520 Mon.
