Confirmation of a highly variable Super Soft Source phase in the recurrent Nova V3890 Sgr by the Swift-XRT
ATel #13104; A. P. Beardmore, J. P. Osborne, K. L. Page (U. Leicester), J. U. Ness (ESAC/ESA), M. Orio (INAF Padova and U. Wisconsin) and J. J. Drake (CfA)
on 13 Sep 2019; 15:24 UT
Credential Certification: Andy Beardmore (apb@star.le.ac.uk)
Following the end of a Moon observing constraint, monitoring of the
recurrent nova V3890 Sgr resumed with the X-ray Telescope (XRT)
onboard the Neil Gehrels Swift observatory at 00:37UT on 2019-Sep-10,
in order to study the evolution of the Super Soft Source flux which
first appeared on 2019-Sep-05 (i.e., 8.39 days after the optical
discoveryl; see ATel#13084).
The six most recent observations taken from 2019-Sep-11 23:04 UT
to 2019-Sep-13 00:14 UT (i.e., day 15.09 to 16.14) reveal a highly
variable soft X-ray source, with a 0.3-10.0 keV XRT count rate
varying between 3.7 c/s to 26.7 c/s. The changes in count rate are
confined to the SSS component below 1 keV. The flux variations are
larger than those initially identified by NICER and the AstroSat Soft
X-ray Telescope on day 9 (ATels #13086 and #13102). The variable soft
X-ray component is similar to those seen in other novae during the
early SSS phase, such as RS Oph (ATel#770) and KT Eri (ATel#2392).
We note that observations of this interesting nova are scheduled to take
place with XMM-Newton from 2019-Sep-14 23:30 UT to 2019-Sep-15 06:27 UT.
Simultaneous observations with other observatories are encouraged.
We thank the Swift PI, Brad Cenko, for approving the monitoring
campaign, as well as the Swift planning and operations teams for their
continuing support.
