TITLE: GCN CIRCULAR NUMBER: 36278 SUBJECT: LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts DATE: 24/04/24 08:42:33 GMT FROM: Phil Evans at U of Leicester pae9@star.le.ac.uk

P.A. Evans (U. Leicester), K.L. Page (U. Leicester), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), S.B. Cenko (NASA/GSFC), R.A.J. Eyles-Ferris (U. Leicester), A.P. Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), A.A. Breeveld (UCL-MSSL), S. Campana (INAF-OAB), M. De Pasquale (University of Messina), S. Dichiara (PSU), P. D’Avanzo (INAF-OAB), A. D’Aì (INAF-IASFPA) , V. D’Elia (ASI-SSDC & INAF-OAR), C. Gronwall (PSU), D. Hartmann (Clemson University), N. Klingler (NASA-GSFC / UMBC / CRESST II), N.P.M. Kuin (UCL-MSSL), S. Laha (NASA/GSFC), S.R. Oates (U. Birmingham), J.P. Osborne (U. Leicester), P. O’Brien (U. Leicester), M.J. Page (UCL-MSSL), G. Raman (PSU) S. Ronchini (PSU), T. Sbarrato (INAF-OAB), B. Sbarufatti (INAF-OAB), M.H. Siegel (PSU), G. Tagliaferri (INAF-OAB), E. Troja (U Tor Vergata, INAF) report on behalf of the Swift team:

Swift has carried out 92 observations of the LVC error region for the GW trigger S240422ed convolved with the 2MPZ catalogue (Bilicki et al. 2014, ApJS, 210, 9), using 76 fields from the 'BAYESTAR' GW localisation map and 16 fields from the 'ligo-skymap-from-samples' GW localisation map. As these are 3D skymaps, galaxy distances were taken into account in selecting which ones to observe. The observations currently span from 10 ks to 90 ks after the LVC trigger, and the XRT has covered 10.1 deg^2 on the sky (corrected for overlaps). This covers 4.5% of the probability in the 'ligo-skymap-from-samples' (version ligo-skymap-from-samples.fits.gz) skymap, and 19% after convolving with the 2MPZ galaxy catalogue, as described by Evans et al. (2016, MNRAS, 462, 1591). Using the earlier 'BAYESTAR' (version BAYESTAR.fits.gz) skymap our observations cover 5.3% of the probability (19% when convolved). These pointings and associated metadata have been reported to the Treasure Map (Wyatt et al., 2020, ApJ, 894, 127; http://treasuremap.space/alerts?graceids=S240422ed).

3 rank 2 sources have been found. These are candidates to be the counterpart to the GW trigger. Details of these sources are:

Source S240422ed_X61: ===================== RA: 120.3245 ( = 08h 01m 17.88s) J2000 Dec: -28.1765 ( = -28d 10' 35.4") J2000 Error: 5.1 (arcsec, radius, 90% confidence). Peak Rate: 8.3e-02 +/- 3.0e-02 ct s^-1 (0.3-10 keV) Peak Flux: 3.5e-12 +/- 1.3e-12 erg cm^-2 s^-1 (0.3-10 keV) Catalogued: No RASS UL: 3.3e-02 ct s^-1 (converted to XRT; 0.3-10 keV) so the source is not above the RASS 3-sigma upper limit.

The source IS FADING at the 3.0-sigma level.

NOTE: this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent (within 3-sigma) with the distance to the GW object.

Source S240422ed_X101: ====================== RA: 122.3954 ( = 08h 09m 34.90s) J2000 Dec: -24.3272 ( = -24d 19' 37.9") J2000 Error: 6.6 (arcsec, radius, 90% confidence). Peak Rate: 1.0e-01 +/- 3.1e-02 ct s^-1 (0.3-10 keV) Peak Flux: 4.4e-12 +/- 1.3e-12 erg cm^-2 s^-1 (0.3-10 keV) Catalogued: No RASS UL: 2.6e-02 ct s^-1 (converted to XRT; 0.3-10 keV) so the source is not above the RASS 3-sigma upper limit.

The source IS FADING at the 3.5-sigma level.

NOTE: this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent (within 3-sigma) with the distance to the GW object.

Source S240422ed_X190: ====================== RA: 121.2770 ( = 08h 05m 06.48s) J2000 Dec: -26.1203 ( = -26d 07' 13.1") J2000 Error: 5.3 (arcsec, radius, 90% confidence). Peak Rate: 2.0e+00 +/- 5.2e-01 ct s^-1 (0.3-10 keV) Peak Flux: 8.4e-11 +/- 2.2e-11 erg cm^-2 s^-1 (0.3-10 keV) Catalogued: No RASS UL: 2.2e-02 ct s^-1 (converted to XRT; 0.3-10 keV) so the source is not above the RASS 3-sigma upper limit.

There is no evidence for fading.

NOTE: this source is NOT within 200 kpc of a GWGC or 2MPZ galaxy which is consistent (within 3-sigma) with the distance to the GW object.

NOTE: This source is in a very noisy XRT field and it may not be real: we will request a follow-up observation.

In total, we have detected 232 X-ray sources. Each source is assigned a rank of 1-4 which describes how likely it is to be related to the GW trigger, with 1 being the most likely and 4 being the least likely. The ranks are described at https://www.swift.ac.uk/ranks.php.

We have found:

* 0 sources of rank 1 * 3 sources of rank 2 * 221 sources of rank 3 * 8 sources of rank 4

RANK 3 sources ==============

These are uncatalogued X-ray sources, however they are not brighter than previous upper limits, so do not stand out as likely counterparts to the GW trigger.

| Source ID | RA | Dec | Err90 | | S240422ed_X2 | 08h 04m 43.19s | -23d 37' 24.0" | 6.7" | | S240422ed_X4 | 08h 08m 39.34s | -18d 23' 50.4" | 6.4" | | S240422ed_X5 | 07h 58m 51.02s | -22d 17' 16.6" | 8.4" | | S240422ed_X6 | 07h 58m 47.06s | -22d 19' 26.6" | 7.5" | | S240422ed_X7 | 07h 58m 41.54s | -22d 13' 08.6" | 8.7" | | S240422ed_X8 | 07h 58m 19.82s | -22d 24' 05.6" | 9.0" | | S240422ed_X9 | 07h 58m 00.71s | -22d 21' 34.1" | 6.7" | | S240422ed_X10 | 08h 00m 49.40s | -22d 20' 59.6" | 6.1" | | S240422ed_X11 | 08h 00m 22.80s | -22d 33' 38.2" | 7.5" | | S240422ed_X12 | 08h 07m 15.82s | -15d 17' 34.9" | 6.6" | | S240422ed_X14 | 07h 58m 02.82s | -21d 57' 15.2" | 7.2" | | S240422ed_X16 | 07h 57m 56.03s | -22d 03' 12.6" | 6.2" | | S240422ed_X17 | 07h 58m 19.62s | -22d 11' 25.7" | 6.0" | | S240422ed_X18 | 07h 57m 56.36s | -22d 04' 01.4" | 8.0" | | S240422ed_X21 | 07h 57m 54.83s | -22d 10' 00.4" | 8.5" | | S240422ed_X22 | 08h 15m 58.64s | -17d 22' 35.3" | 5.9" | | S240422ed_X23 | 08h 09m 56.11s | -21d 32' 55.6" | 8.8" | | S240422ed_X24 | 08h 10m 23.64s | -18d 19' 04.7" | 7.6" | | S240422ed_X25 | 08h 10m 14.18s | -18d 21' 09.1" | 10.6" | | S240422ed_X26 | 08h 09m 51.65s | -18d 11' 17.5" | 9.1" | | S240422ed_X27 | 08h 09m 39.34s | -18d 17' 48.1" | 8.2" | | S240422ed_X28 | 08h 09m 41.22s | -18d 25' 48.1" | 7.0" | | S240422ed_X29 | 08h 09m 12.43s | -18d 23' 13.5" | 8.8" | | S240422ed_X30 | 08h 09m 47.31s | -18d 26' 04.3" | 6.9" | | S240422ed_X31 | 08h 09m 33.65s | -18d 24' 32.0" | 6.1" | | S240422ed_X32 | 07h 58m 47.43s | -22d 08' 43.6" | 15.9" | | S240422ed_X33 | 08h 05m 01.75s | -28d 25' 44.4" | 6.8" | | S240422ed_X34 | 08h 04m 34.26s | -28d 12' 37.1" | 9.2" | | S240422ed_X35 | 08h 05m 33.59s | -28d 13' 27.9" | 7.3" | | S240422ed_X36 | 08h 05m 42.68s | -28d 19' 58.0" | 7.6" | | S240422ed_X37 | 08h 05m 09.97s | -28d 16' 48.6" | 5.7" | | S240422ed_X38 | 08h 05m 45.16s | -28d 21' 01.4" | 6.6" | | S240422ed_X39 | 08h 05m 52.57s | -28d 18' 46.9" | 6.0" | | S240422ed_X40 | 08h 04m 41.41s | -28d 11' 57.8" | 5.5" | | S240422ed_X41 | 08h 05m 42.43s | -28d 24' 19.3" | 6.5" | | S240422ed_X42 | 08h 04m 52.35s | -28d 28' 09.7" | 5.7" | | S240422ed_X43 | 08h 04m 53.26s | -28d 10' 57.2" | 5.6" | | S240422ed_X44 | 08h 09m 09.81s | -18d 14' 19.8" | 7.3" | | S240422ed_X45 | 08h 09m 23.24s | -18d 20' 00.8" | 6.1" | | S240422ed_X46 | 07h 57m 28.64s | -22d 12' 32.3" | 6.0" | | S240422ed_X47 | 07h 58m 40.23s | -22d 22' 38.5" | 13.7" | | S240422ed_X48 | 07h 59m 34.40s | -22d 17' 46.2" | 11.7" | | S240422ed_X49 | 07h 58m 24.50s | -22d 23' 26.8" | 6.8" | | S240422ed_X50 | 08h 00m 13.07s | -22d 32' 47.5" | 6.5" | | S240422ed_X51 | 08h 05m 21.65s | -23d 53' 32.3" | 17.6" | | S240422ed_X52 | 08h 04m 21.05s | -27d 51' 35.2" | 7.2" | | S240422ed_X53 | 08h 03m 36.15s | -27d 42' 01.7" | 6.4" | | S240422ed_X54 | 08h 03m 47.04s | -27d 55' 19.2" | 9.0" | | S240422ed_X55 | 08h 02m 01.17s | -28d 22' 57.3" | 5.1" | | S240422ed_X56 | 08h 05m 41.74s | -28d 14' 26.6" | 6.3" | | S240422ed_X57 | 08h 01m 49.87s | -29d 25' 59.9" | 18.1" | | S240422ed_X58 | 08h 02m 57.63s | -29d 26' 03.6" | 8.8" | | S240422ed_X59 | 08h 01m 50.05s | -28d 18' 01.6" | 5.9" | | S240422ed_X60 | 08h 02m 04.53s | -29d 20' 01.5" | 8.0" | | S240422ed_X62 | 08h 01m 53.82s | -28d 22' 53.5" | 5.9" | | S240422ed_X63 | 08h 00m 50.67s | -30d 30' 24.5" | 7.6" | | S240422ed_X64 | 08h 05m 05.17s | -28d 28' 42.9" | 5.7" | | S240422ed_X65 | 08h 01m 23.18s | -28d 27' 21.4" | 13.0" | | S240422ed_X66 | 08h 02m 40.39s | -22d 35' 42.0" | 5.8" | | S240422ed_X67 | 08h 02m 29.38s | -25d 57' 49.1" | 10.4" | | S240422ed_X68 | 08h 08m 43.37s | -23d 37' 34.1" | 5.5" | | S240422ed_X69 | 08h 07m 30.28s | -23d 34' 03.4" | 6.6" | | S240422ed_X70 | 08h 07m 46.09s | -23d 33' 27.0" | 21.2" | | S240422ed_X71 | 08h 03m 12.73s | -27d 44' 20.2" | 5.6" | | S240422ed_X72 | 08h 03m 50.59s | -27d 40' 12.6" | 6.0" | | S240422ed_X73 | 08h 04m 15.34s | -27d 48' 20.9" | 6.5" | | S240422ed_X74 | 08h 03m 42.64s | -27d 47' 17.4" | 9.3" | | S240422ed_X75 | 08h 03m 39.57s | -27d 40' 24.7" | 5.5" | | S240422ed_X76 | 08h 03m 09.92s | -27d 51' 26.5" | 5.8" | | S240422ed_X78 | 08h 03m 44.46s | -27d 38' 25.0" | 6.0" | | S240422ed_X79 | 08h 04m 19.22s | -27d 45' 54.7" | 14.0" | | S240422ed_X81 | 08h 03m 55.28s | -27d 39' 33.2" | 5.5" | | S240422ed_X83 | 08h 03m 22.60s | -27d 40' 46.2" | 5.1" | | S240422ed_X84 | 08h 04m 20.06s | -25d 14' 47.2" | 6.6" | | S240422ed_X85 | 08h 04m 09.38s | -25d 09' 29.1" | 6.0" | | S240422ed_X86 | 08h 05m 05.57s | -25d 13' 20.9" | 6.2" | | S240422ed_X87 | 08h 05m 07.42s | -25d 10' 46.8" | 6.2" | | S240422ed_X88 | 08h 04m 49.42s | -25d 20' 49.6" | 5.6" | | S240422ed_X89 | 08h 06m 24.02s | -25d 57' 50.6" | 5.9" | | S240422ed_X90 | 08h 05m 30.96s | -25d 52' 08.9" | 6.9" | | S240422ed_X91 | 08h 05m 53.97s | -26d 07' 17.3" | 5.4" | | S240422ed_X92 | 08h 06m 26.93s | -26d 02' 22.8" | 6.6" | | S240422ed_X93 | 08h 05m 50.43s | -25d 50' 09.4" | 6.5" | | S240422ed_X94 | 08h 05m 17.51s | -26d 01' 16.5" | 5.6" | | S240422ed_X95 | 08h 05m 17.32s | -25d 57' 33.6" | 7.9" | | S240422ed_X96 | 08h 05m 46.88s | -25d 50' 22.5" | 7.9" | | S240422ed_X97 | 08h 05m 44.78s | -25d 49' 06.8" | 7.4" | | S240422ed_X98 | 08h 06m 22.66s | -26d 00' 00.5" | 9.0" | | S240422ed_X99 | 08h 06m 29.45s | -26d 00' 10.6" | 8.8" | | S240422ed_X100 | 08h 05m 02.54s | -25d 56' 13.9" | 8.1" | | S240422ed_X103 | 08h 02m 37.62s | -26d 04' 28.5" | 7.8" | | S240422ed_X104 | 08h 02m 52.95s | -25d 52' 07.3" | 5.9" | | S240422ed_X105 | 08h 07m 25.94s | -23d 38' 14.9" | 9.5" | | S240422ed_X106 | 08h 08m 06.73s | -23d 27' 56.3" | 6.7" | | S240422ed_X107 | 08h 05m 17.75s | -25d 56' 42.1" | 5.7" | | S240422ed_X113 | 08h 25m 27.91s | -20d 20' 51.8" | 5.4" | | S240422ed_X114 | 08h 24m 06.00s | -20d 17' 30.8" | 6.1" | | S240422ed_X115 | 08h 17m 16.80s | -18d 34' 49.1" | 6.5" | | S240422ed_X116 | 08h 16m 57.94s | -18d 36' 35.4" | 6.1" | | S240422ed_X117 | 08h 10m 17.16s | -18d 08' 25.3" | 6.5" | | S240422ed_X119 | 08h 11m 02.83s | -18d 06' 30.8" | 6.4" | | S240422ed_X120 | 08h 10m 40.03s | -17d 57' 24.6" | 7.9" | | S240422ed_X121 | 08h 10m 18.17s | -18d 16' 06.4" | 6.7" | | S240422ed_X122 | 08h 10m 03.03s | -18d 11' 37.4" | 15.7" | | S240422ed_X123 | 08h 10m 16.23s | -18d 19' 39.6" | 6.8" | | S240422ed_X124 | 08h 10m 24.70s | -18d 16' 17.7" | 6.1" | | S240422ed_X125 | 08h 11m 35.67s | -17d 56' 05.8" | 5.8" | | S240422ed_X126 | 08h 10m 38.19s | -18d 22' 21.0" | 5.8" | | S240422ed_X127 | 08h 09m 55.62s | -18d 18' 02.4" | 9.0" | | S240422ed_X128 | 08h 11m 19.81s | -18d 00' 36.6" | 6.0" | | S240422ed_X129 | 08h 09m 56.24s | -18d 15' 51.5" | 8.6" | | S240422ed_X130 | 08h 10m 14.29s | -18d 15' 08.6" | 7.2" | | S240422ed_X131 | 08h 10m 05.28s | -18d 16' 22.0" | 6.6" | | S240422ed_X132 | 08h 10m 54.98s | -17d 46' 59.2" | 6.0" | | S240422ed_X133 | 08h 10m 55.47s | -17d 55' 36.3" | 5.3" | | S240422ed_X134 | 08h 09m 48.80s | -18d 09' 58.4" | 6.8" | | S240422ed_X135 | 08h 10m 02.96s | -18d 16' 16.8" | 6.5" | | S240422ed_X136 | 08h 11m 40.95s | -18d 00' 38.9" | 5.0" | | S240422ed_X137 | 08h 10m 59.88s | -17d 47' 27.4" | 6.2" | | S240422ed_X138 | 08h 10m 21.49s | -18d 20' 23.1" | 5.7" | | S240422ed_X140 | 08h 10m 28.48s | -18d 01' 55.9" | 5.7" | | S240422ed_X141 | 08h 11m 20.29s | -18d 03' 59.4" | 5.7" | | S240422ed_X142 | 08h 10m 13.99s | -18d 09' 21.1" | 6.3" | | S240422ed_X143 | 08h 09m 55.96s | -18d 12' 27.7" | 6.3" | | S240422ed_X144 | 08h 10m 04.29s | -18d 18' 33.4" | 7.1" | | S240422ed_X145 | 08h 10m 12.97s | -18d 16' 47.6" | 6.7" | | S240422ed_X146 | 08h 10m 54.91s | -18d 22' 38.5" | 6.0" | | S240422ed_X147 | 08h 10m 04.19s | -18d 07' 18.2" | 11.3" | | S240422ed_X148 | 08h 10m 08.39s | -18d 18' 15.0" | 6.3" | | S240422ed_X149 | 08h 11m 20.72s | -18d 17' 09.0" | 9.5" | | S240422ed_X150 | 08h 09m 50.26s | -18d 15' 21.7" | 8.8" | | S240422ed_X151 | 08h 10m 01.15s | -18d 19' 55.1" | 6.6" | | S240422ed_X152 | 08h 11m 24.09s | -17d 49' 54.0" | 6.7" | | S240422ed_X153 | 08h 10m 09.02s | -18d 21' 06.4" | 6.1" | | S240422ed_X154 | 08h 12m 14.52s | -18d 48' 29.7" | 8.7" | | S240422ed_X155 | 08h 12m 40.59s | -18d 38' 36.0" | 12.8" | | S240422ed_X156 | 08h 13m 21.01s | -18d 56' 52.6" | 8.6" | | S240422ed_X157 | 08h 12m 48.62s | -18d 59' 37.5" | 7.3" | | S240422ed_X158 | 08h 12m 28.74s | -18d 48' 37.0" | 6.6" | | S240422ed_X161 | 08h 26m 34.51s | -21d 01' 50.6" | 5.9" | | S240422ed_X162 | 08h 25m 20.03s | -20d 21' 21.4" | 6.0" | | S240422ed_X163 | 08h 25m 18.09s | -20d 15' 06.5" | 5.8" | | S240422ed_X164 | 08h 24m 32.58s | -20d 14' 53.8" | 6.8" | | S240422ed_X165 | 08h 25m 50.04s | -20d 59' 25.8" | 5.1" | | S240422ed_X166 | 08h 26m 08.36s | -20d 58' 38.7" | 6.1" | | S240422ed_X167 | 08h 26m 17.04s | -20d 58' 15.6" | 6.3" | | S240422ed_X168 | 08h 25m 34.66s | -20d 18' 29.5" | 5.9" | | S240422ed_X169 | 08h 24m 57.04s | -20d 26' 50.5" | 8.4" | | S240422ed_X170 | 08h 26m 16.63s | -20d 39' 49.0" | 7.1" | | S240422ed_X171 | 08h 24m 52.75s | -20d 26' 15.5" | 5.3" | | S240422ed_X172 | 08h 08m 04.35s | -23d 24' 45.1" | 8.5" | | S240422ed_X173 | 08h 08m 11.03s | -23d 25' 15.4" | 8.8" | | S240422ed_X174 | 08h 03m 49.36s | -26d 13' 42.2" | 9.3" | | S240422ed_X175 | 08h 03m 28.16s | -26d 17' 32.7" | 5.7" | | S240422ed_X176 | 08h 03m 23.77s | -26d 19' 42.3" | 5.9" | | S240422ed_X177 | 08h 05m 10.86s | -25d 58' 40.0" | 12.0" | | S240422ed_X178 | 08h 05m 32.41s | -26d 03' 59.8" | 5.9" | | S240422ed_X179 | 08h 04m 43.40s | -26d 03' 22.6" | 5.6" | | S240422ed_X180 | 08h 02m 45.33s | -26d 25' 14.7" | 5.4" | | S240422ed_X181 | 08h 05m 16.90s | -26d 09' 00.2" | 7.3" | | S240422ed_X182 | 08h 02m 58.18s | -25d 50' 21.3" | 8.6" | | S240422ed_X183 | 08h 03m 40.30s | -26d 03' 00.2" | 6.9" | | S240422ed_X184 | 08h 02m 33.85s | -26d 05' 25.7" | 6.4" | | S240422ed_X185 | 08h 03m 38.73s | -26d 22' 16.1" | 6.2" | | S240422ed_X186 | 08h 03m 05.19s | -25d 50' 21.8" | 7.5" | | S240422ed_X187 | 08h 05m 26.00s | -25d 57' 35.1" | 7.8" | | S240422ed_X188 | 08h 03m 02.65s | -25d 48' 22.2" | 7.9" | | S240422ed_X189 | 08h 02m 43.04s | -25d 49' 50.3" | 6.4" | | S240422ed_X191 | 08h 04m 42.44s | -25d 47' 20.1" | 5.3" | | S240422ed_X192 | 08h 03m 04.32s | -26d 27' 12.7" | 6.8" | | S240422ed_X193 | 08h 02m 56.44s | -26d 07' 22.2" | 6.5" | | S240422ed_X194 | 08h 05m 21.31s | -25d 51' 58.6" | 7.5" | | S240422ed_X195 | 08h 04m 26.43s | -25d 18' 43.9" | 5.6" | | S240422ed_X196 | 08h 04m 39.38s | -25d 50' 26.3" | 6.1" | | S240422ed_X197 | 08h 03m 33.96s | -25d 50' 24.0" | 7.0" | | S240422ed_X198 | 08h 05m 39.81s | -26d 03' 05.6" | 6.0" | | S240422ed_X199 | 08h 05m 24.57s | -26d 04' 33.4" | 6.7" | | S240422ed_X200 | 08h 05m 25.64s | -26d 03' 20.3" | 6.0" | | S240422ed_X201 | 08h 05m 29.95s | -26d 02' 04.2" | 5.9" | | S240422ed_X202 | 08h 04m 46.81s | -25d 52' 01.2" | 7.1" | | S240422ed_X203 | 08h 06m 04.46s | -26d 02' 57.8" | 5.3" | | S240422ed_X204 | 08h 04m 59.49s | -26d 05' 48.9" | 7.4" | | S240422ed_X205 | 08h 03m 42.53s | -26d 13' 58.9" | 5.6" | | S240422ed_X206 | 08h 02m 34.55s | -25d 49' 17.4" | 6.3" | | S240422ed_X207 | 08h 05m 12.38s | -25d 48' 58.6" | 5.5" | | S240422ed_X208 | 08h 02m 22.50s | -26d 24' 00.6" | 6.6" | | S240422ed_X209 | 08h 02m 18.98s | -25d 57' 28.4" | 7.3" | | S240422ed_X210 | 08h 04m 46.12s | -26d 03' 37.3" | 9.4" | | S240422ed_X211 | 08h 03m 16.95s | -25d 53' 01.3" | 6.5" | | S240422ed_X212 | 08h 03m 20.75s | -26d 11' 31.0" | 6.6" | | S240422ed_X213 | 08h 04m 30.57s | -25d 51' 33.7" | 5.9" | | S240422ed_X214 | 08h 03m 15.45s | -26d 02' 27.9" | 6.0" | | S240422ed_X215 | 08h 05m 11.27s | -25d 53' 49.9" | 7.6" | | S240422ed_X216 | 08h 01m 49.79s | -29d 38' 11.0" | 7.3" | | S240422ed_X217 | 08h 03m 17.43s | -27d 52' 09.5" | 5.9" | | S240422ed_X218 | 08h 04m 14.00s | -27d 51' 44.9" | 7.6" | | S240422ed_X219 | 08h 03m 37.04s | -27d 55' 52.6" | 5.3" | | S240422ed_X220 | 08h 03m 23.37s | -27d 46' 53.2" | 6.4" | | S240422ed_X221 | 08h 03m 42.72s | -27d 38' 55.6" | 6.9" | | S240422ed_X222 | 08h 10m 21.80s | -18d 17' 01.0" | 7.0" | | S240422ed_X223 | 08h 08m 49.73s | -24d 31' 22.8" | 5.4" | | S240422ed_X224 | 08h 02m 12.90s | -26d 23' 02.9" | 5.7" | | S240422ed_X225 | 08h 11m 27.69s | -18d 04' 50.0" | 6.6" | | S240422ed_X226 | 08h 10m 08.95s | -18d 12' 17.6" | 7.3" | | S240422ed_X227 | 08h 08m 55.49s | -24d 30' 23.8" | 6.6" | | S240422ed_X229 | 08h 03m 28.50s | -26d 24' 13.0" | 5.5" | | S240422ed_X230 | 08h 10m 22.31s | -18d 19' 53.3" | 11.8" | | S240422ed_X231 | 08h 02m 48.21s | -25d 56' 51.6" | 6.0" | | S240422ed_X232 | 08h 10m 29.42s | -18d 12' 48.5" | 15.2" | | S240422ed_X234 | 08h 10m 04.02s | -18d 08' 27.8" | 9.0" | | S240422ed_X235 | 08h 26m 17.31s | -27d 22' 40.3" | 16.4" | | S240422ed_X236 | 08h 03m 03.62s | -26d 25' 04.6" | 7.4" | | S240422ed_X237 | 08h 04m 45.90s | -26d 09' 23.9" | 7.6" | | S240422ed_X238 | 08h 10m 30.49s | -18d 15' 43.4" | 6.0" | | S240422ed_X239 | 08h 05m 22.47s | -26d 01' 39.7" | 5.6" | | S240422ed_X240 | 08h 08m 53.52s | -24d 31' 51.8" | 5.8" | | S240422ed_X241 | 08h 04m 37.23s | -25d 54' 54.2" | 6.2" | | S240422ed_X242 | 08h 02m 58.11s | -26d 16' 58.3" | 5.9" | | S240422ed_X243 | 08h 05m 23.08s | -25d 59' 52.9" | 6.9" | | S240422ed_X244 | 08h 04m 38.78s | -26d 09' 49.1" | 6.7" | | S240422ed_X245 | 08h 02m 44.53s | -26d 04' 22.9" | 6.7" |

RANK 4 sources ==============

These are catalogued X-ray sources, showing no signs of outburst compared to previous observations, so they are not likely to be related to the GW trigger.

| Source ID | RA | Dec | Err90 | | S240422ed_X3 | 07h 57m 58.98s | -21d 57' 37.8" | 8.4" | | S240422ed_X15 | 07h 58m 49.93s | -22d 00' 19.8" | 4.9" | | S240422ed_X20 | 07h 58m 00.02s | -21d 57' 16.8" | 12.9" | | S240422ed_X102 | 08h 09m 55.15s | -24d 01' 38.6" | 4.8" | | S240422ed_X139 | 08h 10m 27.22s | -18d 11' 38.3" | 9.0" | | S240422ed_X233 | 08h 09m 03.03s | -24d 27' 11.1" | 7.2" | | S240422ed_X247 | 08h 09m 43.99s | -23d 58' 38.1" | 8.4" | | S240422ed_X248 | 08h 13m 04.13s | -29d 01' 53.2" | 6.8" |

For all flux conversions and comparisons with catalogues and upper limits from other missions, we assumed a power-law spectrum with NH=3x10^20 cm^-2, and photon index (Gamma)=1.7, unless otherwise stated.

The results of the XRT automated analysis, including details of the sources listed above, are online at https://www.swift.ac.uk/LVC/S240422ed

This circular is an official product of the Swift XRT team.

View this GCN Circular online at https://gcn.nasa.gov/circulars/36278. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...