GCN Circular 38381
Subject
Swift-XRT observations of IceCube -241127A
Date
2024-11-29T14:11:26Z (2 months ago)
From
P.A. Evans at U. Leicester <pae9@leicester.ac.uk>
Via
Web form
P.A. Evans (U. Leicester) and J.A. Kennea (PSU) report on behalf of the Swift-XRT team,
Swift-XRT observed the field of IceCube-241127A (IceCube Collaboration, GCN 38349) between 18:51 and 22:12 UT on 2024 November 27 (16.8 to 29.4 ks after the trigger), gathering 4.7 ks over 10 pointings centred on the neutrino position.
One X-ray source is detected at a RA, Dec = 164.0502° 5.2615, which is equivalent to:
RA (J2000) = 10h 56m 12.04s
Dec (J2000) = +05d 15’ 41.3S"
with an uncertainty of 8.4 arcseconds (radius, 90 confidence). This is consistent with the a known X-ray source from the Swift [LSXPS](https://www.swift.ac.uk/LSXPS/) catalogue: [LSXPS J105612.0+051546](https://www.swift.ac.uk/LSXPS/LSXPS%20J105612.0%2B051546); and the optical galaxy SDSS J105612.22+051544.6. The count-rate in the historical Swift data is 0.023 (+0.007, -0.006) ct/sec; in the new observations the count-rate is 0.015 (+0.006, -0.005); i.e. the source shows no signs of outburst.
Three other objects were found, all of which are rated “poor” by the detection algorithm which corresponds to a ~1 sigma detection, their details are below (all positions in J2000, errors are arcseconds, 90% confidence).
SWIFT J105542.0+051112 (source 2):
RA: 10h 55m 42.04s (= 163.9252)
Dec: +05d 11’ 12.1" (= +5.1867)
Error: 7.0
This source is 2.1 arcseconds from the radio source NVSS J105542+051112.
SWIFT J105615.1+051437 (source 3):
RA: 10h 56m 15.13s (= 164.0630)
Dec: +05d 14’ 37.7" (= +5.2438)
Error: 8.2
SWIFT J105711.6+054504 (source 4):
RA (J2000): 10h 57m 11.64s (= 164.2985)
Dec (J2000): +05d 45’ 04.8" (= +5.7513)
Error: 7.6
This source is 10.6 arseconds from the high proper-motion star PM J10571+0544A, and 13arcseconds
from the Rosat source: 1RXS J105710.9+054458.
The Rosat brightness is equivalent to 0.048 +/- 0.011 ct/sec in XRT (assuming a power-law spectrum, photon index 1.7, nH = 3e20 cm^-2); the XRT count-rate is 0.013 (+0.008, -0.006); this this possible source also shows no evidence for an outburst.
The full XRT analysis can be viewed online at https://www.swift.ac.uk/neutrino/NEUTRINO_FIELD00042/.