[vsnet-grb-info 23885] LIGO/Virgo S190930t: Continued Swift observations of AT2019sbk

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25984
SUBJECT: LIGO/Virgo S190930t: Continued Swift observations of AT2019sbk
DATE:    19/10/08 16:54:30 GMT
FROM:    Samantha Oates at MSSL  <sro at mssl.ucl.ac.uk>

S. R. Oates (Uni. of Warwick), N. P. M. Kuin (UCL-MSSL), A. A. Breeveld (MSSL-UCL),
A. Tohuvavohu (U. Toronto), J. A. Kennea (PSU), F. E. Marshall (NASA/GSFC),
P. Brown (TAMU), C. Gronwall (PSU), M. J. Page (UCL-MSSL),
M. De Pasquale (Istanbul U.), M. H. Siegel (PSU), A. D'Ai (INAF-IASFPA),
P. D'Avanzo (INAF-OAB), S. D. Barthelmy (NASA/GSFC), A. P. Beardmore (U. Leicester),
D. N. Burrows (PSU), S. Campana (INAF-OAB), S. B. Cenko (NASA/GSFC),
G. Cusumano (INAF-IASF PA), V. D'Elia(ASDC), P. A. Evans (U. Leicester),
P. Giommi (ASI), D. Hartmann (Clemson U.),  N. J. Klingler (PSU),
H. A. Krimm (NSF), A. Y. Lien (GSFC/UMBC), D. B. Malesani (DTU Space),
A. Melandri (INAF-OAB),  J. A. Nousek (PSU), P. T. O'Brien (U. Leicester),
J. P. Osborne (U. Leicester), C. Pagani (U. Leicester), K. L. Page (U.Leicester),
D.M. Palmer (LANL),  M. Perri (ASDC), J. L. Racusin (NASA/GSFC),
T. Sakamoto (AGU),  B. Sbarufatti (INAF-OAB/PSU), G. Tagliaferri (INAF-OAB),
and E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift team:

Starting 2019-10-07 at 15:58:58 UT (GW T0+169 hours) Swift/UVOT reobserved
the field of AT2019sbk (Tohuvavohu et al., GCN Circ. 25964), a candidate
transient found in the UVOT search results of the LVC event S190930t
(LIGO/VIRGO Collaboration GCN Circ. 25876).

In total 2.7 ks were observed with the u band (observation ID 07021863003). The
transient reported in Tohuvavohu et al. (GCN Circ. 25964) can no longer be discerned
from the underlying host galaxy. 

We also have an improvement on the position of the XRT source reported
in Tohuvavohu et al. (GCN Circ. 25964). The new UVOT enhanced XRT position is:

RA(J2000) =   22:47:18.46 = 341.82692 deg
Dec(J2000) =  -58:14:41.9 = -58.24498 deg

with an error radius 2.0" (90% confidence). This refined position is ~9 arcsecond
away from the UVOT position of AT2019sbk and is instead consistent with
the centre of the galaxy 2MASX J22471856-5814422. We therefore retract its association
with AT2019sbk.

This circular is an official product of the Swift team.