Swift follow up observation of SRGt J071522.1-191609

ATel #13661; A. Bahramian (Curtin), J. A. Kennea (PSU), G. R. Sivakoff (Alberta), T. J. Maccarone (TexasTech)
on 24 Apr 2020; 10:37 UT
Credential Certification: Arash Bahramian (arash.bahramian@curtin.edu.au)

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Following the discovery of a new transient by SRG/eROSITA (SRGt J071522.1-191609, ATel #13657), we performed a follow up observation by Swift observatory on 2020-04-24 at 00:29:33 (UTC) with the XRT in PC mode and UVOT snapshots in 5 filters (obsid 00013481001). Using the Swift/XRT product builder (https://www.swift.ac.uk/user_objects/), we obtained an enhanced X-ray position of:

RA: 07:15:21.97
Dec: -19:16:05.4

with radial uncertainty of 2.0 arcsec (90% confidence). This is within the 5 arcsec uncertainty radius reported in ATel #13657.

We extracted an X-ray spectrum in the 0.3-10 keV range and fitted with an absorbed power-law (assuming Wilms et al. 2000 abundances and Verner et al. 1996 photoelectric cross-section). We found a best fit model with NH=1.9(-0.7/+1.0)e22 cm^-2, photon index of 2.6(-0.7/+0.8), and an unabsorbed flux of 3.3(-1.3/+4.7)e-11 erg/s/cm^-2 in the 0.5-10 keV band. Extrapolated absorbed flux in the 0.2-10 keV band is 1.1(-0.2/+0.3)e-11 erg/s/cm^-2 consistent with the reported flux by SRG/eROSITA.

We also searched for a UV/optical counterpart to this new transient. However, we found no counterpart in any bands within the 2 arcsec error circle, with 3-sigma upper limits of uw2 > 19.63, uw1 > 19.13, b > 19.81, u > 19.34 and v > 18.31 (Vega magnitudes).