MAXI J1216-655: Swift/XRT non-detection
ATel #13951; J. A. Kennea (PSU), P. A. Evans, A. P. Beardmore (U Leicester), A. Bahramian (ICRAR), H. A. Krimm (NSF/USRA), P. Romano (INAF-OAB), K. Yamaoka (Nagoya U.), M. Serino (RIKEN) and H. Negoro (Nihon U.)
on 17 Aug 2020; 20:14 UT
Credential Certification: Jamie A. Kennea (kennea@astro.psu.edu)
Subjects: X-ray, Transient
Starting 14:47UT on August 15th, 2020, Swift performed a 7-point tiling with 250s per tile of the new X-ray transient MAXI J1216-655 (ATEL #13946). The MAXI reported error region (without systematic error) was completely covered by the Swift pointings. We did not find any new point sources inside the MAXI error region.
We note that in the XRT data we detect the Supernova Remnant G299.2-02.9 (e.g. Park et al 2007, ApJ, 665, 1173) inside the MAXI error region, however we do not believe that this is related to the MAXI detected outburst.
Given the apparent short outburst time noted in ATEL #13946, and the fact that the MAXI source was first detected 5.5 days before the Swift observations began, this suggests that the proposed VFXT had faded below the level of detectability by Swift in a 250s exposure. We estimate an upper limit on the X-ray flux of 1.5 x 10^-12 erg/s/cm^2 (0.3-10 keV).
