[vsnet-grb-info 23121] LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25220
SUBJECT: LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates in the Swift-XRT Observations
DATE:    19/07/30 00:44:43 GMT
FROM:    Azadeh Keivani at Columbia U  <azadeh.keivani at columbia.edu>

LIGO/Virgo S190728q/IceCube neutrino candidate: No counterpart candidates
in the Swift-XRT Observations

A. Tohuvavohu (PSU), A. Keivani (Columbia U.),  J. A. Kennea (PSU), P. A.
Evans (U. Leicester), S. Countryman (Columbia U.), Z. Marka (Columbia U.),
S. Marka (Columbia U.), I. Bartos (U. Florida), D. B. Fox (PSU)

The Neil Gehrels Swift Observatory observed the field of the IceCube
track-like muon neutrino candidate (RA, Dec = 312.87d, 5.85d; GCN #25210)
consistent with the sky localization of gravitational-wave candidate
S190728q (GCN #25187) covering ~14.5 sq degrees in 145 tiles (tiling map at
this url: https://tinyurl.com/y52pug65), to cover the most probable regions
of the joint GW and neutrino localization (90%-containment radius: 4.8d).
The observations start from 19:27 UT on July 28th and ended at 11:41 UT on
July 29, 2019, and achieved an average depth of ~5 x 10^-12 erg s^-1 cm^-2
in soft X-rays (0.3-10 keV).

Three X-ray sources were detected in these observations which all match
known X-ray sources. None of these are above their cataloged flux values.

Source, RA, Dec, XRT count rate (ct s^-1)

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1RXS J205242.6+081039, 313.1760,  8.1785, 0.11 (±0.04)

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1RXS J205421.7+090229, 313.58716, 9.0381, 0.06 (±0.03)

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XMMSL2 J204928.9+060159, 312.37177, 6.0305, 0.11 (±0.04)