Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 18466

LIGO/Virgo G194575: Swift observations
2015-10-24T14:07:34Z (9 years ago)
Phil Evans at U of Leicester <>
P.A. Evans (U. Leicester), J.A. Kennea (PSU), Scott Barthelmy
(NASA/GSFC), Dave Burrows (PSU), Sergio Campana (INAF-OAB), Brad Cenko
(NASA/GSFC), Neil Gehrels (NASA/GSFC), Paolo Giommi (ASI), Frank
Marshall (NASA/GSFC), John Nousek (PSU), Paul O'Brien (U. Leicester),
Julian Osborne (U. Leicester), David Palmer (LANL), Matteo Perri
(ASDC), Judy Racusin (NASA/GSFC), Mike Siegel (PSU), Gianpiero
Tagliaferri (INAF-OAB) report on behalf of the Swift team:

Swift has performed follow up of LVC trigger G194575 (Singer et al., GCN
Circ. 18442). Unfortunately, most of the error region is in Sun
constraint and cannot be observed. We have observed the locations
(observation centres) listed below. No X-ray sources have been found,
nor have any new sources been seen in UVOT. The typical limiting
magnitude is about 18.9 in the u band. In the XRT the 3-sigma upper
limit is in the range 0.007 to 0.015 ct/s, corresponding to a 0.3-10 keV
flux of 3e-13 to 6e-13 erg/cm^2/s.

RA=188.117, Dec=-70.759, exposure=925 s
RA=187.167, Dec=-70.759, exposure=349 s
RA=81.8355, Dec=-4.69639, exposure=880 s
RA=9.77883, Dec=26.2998, exposure=988 s
RA=0.64059, Dec=-60.74, exposure= 993 s

This circular is an official product of the Swift team.
Looking for U.S. government information and services? Visit