S-CUBED detection of new outburst of SMC X-2
ATel #15434; J. A. Kennea (PSU), M. J. Coe (Soton) and P. A. Evans (Leicester)
on 15 Jun 2022; 01:07 UT
Distributed as an Instant Email Notice Transients
Credential Certification: Jamie A. Kennea (kennea@astro.psu.edu)
Subjects: X-ray, Neutron Star, Transient
Referred to by ATel #: 15500
We report on the detection of an X-ray outburst of SMC X-2 by S-CUBED. S-CUBED is a weekly survey of the optical extent of the SMC with the Swift X-ray and UV/Optical Telescopes (Kennea et al., 2018). In the S-CUBED observation of June 14, 2022, we detect an X-ray point source at the a location of RA/Dec(J2000) = 13.63906, -73.68402, which is equivalent to:
RA(J2000) =00h 54m 33.37s,
Dec(J2000) = 73d 41m 02.5s,
with an error radius 4.6 arc-seconds (90% confidence). This position lies 1.2 arc-seconds from the optical counterpart of SMC X-2, confirming the this is the same source.
In the 60s S-CUBED exposure, SMC X-2 is at a brightness of 0.8 +/- 0.3 XRT count/s. The best fit spectrum is a power-law with photon index 1.5 +/- 0.8, with a flux of ~4 x 10^-11 erg/s/cm^2, or a luminosity of 3 x 10^35 erg/s at a standard SMC distance of 62 kpc.
TOO follow-up of SMC X-2 has been requested with Swift to confirm the outburst evolution.
