Gamma-ray Burst 251024A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN/BACODINE POSITION NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:47:58 UT
  NOTICE_TYPE:     Swift-BAT GRB Position
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  GRB_RA:          306.622d {+20h 26m 29s} (J2000),
                   307.245d {+20h 28m 59s} (current),
                   305.405d {+20h 21m 37s} (1950)
  GRB_DEC:         -68.574d {-68d 34' 25"} (J2000),
                   -68.488d {-68d 29' 15"} (current),
                   -68.738d {-68d 44' 15"} (1950)
  GRB_ERROR:       3.00 [arcmin radius, statistical only]
  GRB_INTEN:       17029 [cnts]    Image_Peak=368 [image_cnts]
  TRIGGER_DUR:     8.192 [sec] 
  TRIGGER_INDEX:   477     E_range: 25-100 keV
  BKG_INTEN:       118754 [cnts]
  BKG_TIME:        63931.43 SOD {17:45:31.43} UT
  BKG_DUR:         64 [sec]
  GRB_DATE:        20972 TJD;   297 DOY;   25/10/24
  GRB_TIME:        64022.25 SOD {17:47:02.25} UT
  GRB_PHI:         -41.14 [deg]
  GRB_THETA:        22.24 [deg]
  SOLN_STATUS:     0x3
  RATE_SIGNIF:     10.19 [sigma]
  IMAGE_SIGNIF:    7.19 [sigma]
  MERIT_PARAMS:     +1  +0  +0  +3  +2  -3  +0  +0 -14  +0 
  SUN_POSTN:       209.41d {+13h 57m 39s}  -12.02d {-12d 01' 03"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.01d {+16h 16m 02s}  -26.41d {-26d 24' 19"}
  MOON_DIST:        55.83 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.74 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:      288.82,-47.51 [deg] ecliptic lon,lat of the burst (or transient)
  COMMENTS:        SWIFT-BAT GRB Coordinates.  
  COMMENTS:        This is a rate trigger.  
  COMMENTS:        A point_source was found.  
  COMMENTS:        This does not match any source in the on-board catalog.  
  COMMENTS:        This does not match any source in the ground catalog.  
  COMMENTS:        This is a GRB.  
  COMMENTS:        This trigger occurred at longitude,latitude = 88.26,-13.02 [deg].  
  

• red DSS finding chart ps-file
  
  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:49:16 UT
  NOTICE_TYPE:     Swift-XRT Nack-Position
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.628d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.570d {-68d 34' 10"} (J2000)
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64151.35 SOD {17:49:11.35} UT,   129.1 [sec] since BAT Trigger Time
  COUNTS:          9    Min_needed= 20
  STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
  PH2_ITER:        1    Max_iter_allowed= 4
  ERROR_CODE:      1
  COMMENTS:        SWIFT-XRT Nack Position.  
  COMMENTS:        No source found in the image.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:52:17 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.628d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.570d {-68d 34' 11"} (J2000)
  POINT_ROLL:      258.911d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64154.70 SOD {17:49:14.70} UT,   132.4 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        1.834
  N_STARS:         83
  X_OFFSET:        492 [pixels]
  Y_OFFSET:        525 [pixels]
  X_MAX:           1451 [pixels]
  Y_MAX:           1484 [pixels]
  DET_THRESH:      11
  PHOTO_THRESH:    6
  SL_URL:          sw01406589000msufc0132.fits
  SUN_POSTN:       209.42d {+13h 57m 40s}  -12.02d {-12d 01' 07"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.05d {+16h 16m 11s}  -26.41d {-26d 24' 44"}
  MOON_DIST:        55.81 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:52:32 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.628d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.570d {-68d 34' 11"} (J2000)
  POINT_ROLL:      258.911d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64154.70 SOD {17:49:14.70} UT,   132.4 [sec] since BAT Trigger Time
  FILTER:          10, White
  BKG_MEAN:        1.834
  N_STARS:         83
  X_OFFSET:        492 [pixels]
  Y_OFFSET:        525 [pixels]
  X_MAX:           1451 [pixels]
  Y_MAX:           1484 [pixels]
  DET_THRESH:      11
  PHOTO_THRESH:    6
  SL_URL:          sw01406589000msufc0132.fits
  SUN_POSTN:       209.42d {+13h 57m 40s}  -12.02d {-12d 01' 07"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.05d {+16h 16m 12s}  -26.41d {-26d 24' 45"}
  MOON_DIST:        55.81 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Source List.  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:53:40 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.628d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.570d {-68d 34' 11"} (J2000)
  ROLL:            258.911d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64154.70 SOD {17:49:14.70} UT,   132.4 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     783020991
  X_OFFSET:        811 [pixels]
  Y_OFFSET:        844 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       971
  Y_GRB_POS:       1004
  BINNING_INDEX:   1
  IM_URL:          sw01406589000msuni0169.fits
  SUN_POSTN:       209.42d {+13h 57m 40s}  -12.02d {-12d 01' 08"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.06d {+16h 16m 14s}  -26.41d {-26d 24' 52"}
  MOON_DIST:        55.81 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:53:49 UT
  NOTICE_TYPE:     Swift-UVOT Processed Image
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.628d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.570d {-68d 34' 11"} (J2000)
  ROLL:            258.911d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64154.70 SOD {17:49:14.70} UT,   132.4 [sec] since BAT Trigger Time
  FILTER:          10, White
  EXPOSURE_ID:     783020991
  X_OFFSET:        811 [pixels]
  Y_OFFSET:        844 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       971
  Y_GRB_POS:       1004
  BINNING_INDEX:   1
  IM_URL:          sw01406589000msuni0169.fits
  SUN_POSTN:       209.42d {+13h 57m 40s}  -12.02d {-12d 01' 08"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.06d {+16h 16m 14s}  -26.41d {-26d 24' 53"}
  MOON_DIST:        55.80 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 17:53:26 UT
  NOTICE_TYPE:     Swift-XRT Position
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  GRB_RA:          306.5999d {+20h 26m 23.97s} (J2000),
                   307.2228d {+20h 28m 53.46s} (current),
                   305.3830d {+20h 21m 31.92s} (1950)
  GRB_DEC:         -68.5713d {-68d 34' 16.6"} (J2000),
                   -68.4850d {-68d 29' 05.9"} (current),
                   -68.7349d {-68d 44' 05.7"} (1950)
  GRB_ERROR:       3.5 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       1.00e-10 [erg/cm2/sec]
  GRB_SIGNIF:      10.00 [sigma]
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64187.00 SOD {17:49:47.00} UT,   164.8 [sec] since BAT Trigger Time
  TAM[0-3]:        100.00 100.00 100.00 100.00
  AMPLIFIER:       1
  WAVEFORM:        31
  SUN_POSTN:       209.42d {+13h 57m 40s}  -12.02d {-12d 01' 08"}
  SUN_DIST:         81.66 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.06d {+16h 16m 14s}  -26.41d {-26d 24' 50"}
  MOON_DIST:        55.80 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.74 [deg] galactic lon,lat of the burst
  ECL_COORDS:      288.81,-47.51 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  COMMENTS:        TAM values, flux and significance fields are not valid.  
  COMMENTS:        This position was automatically generated on the ground using  
  COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
  COMMENTS:        See https://www.swift.ac.uk/sper/docs.php for details.  
  COMMENTS:        The probability that this is a serendipitous source in the  
  COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 18:00:20 UT
  NOTICE_TYPE:     Swift-UVOT Source List
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.631d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.571d {-68d 34' 13"} (J2000)
  POINT_ROLL:      258.910d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64312.79 SOD {17:51:52.79} UT,   290.5 [sec] since BAT Trigger Time
  FILTER:          7, U
  BKG_MEAN:        0.522
  N_STARS:         157
  X_OFFSET:        252 [pixels]
  Y_OFFSET:        285 [pixels]
  X_MAX:           1691 [pixels]
  Y_MAX:           1724 [pixels]
  DET_THRESH:      7
  PHOTO_THRESH:    3
  SL_URL:          sw01406589000msufc0290.fits
  SUN_POSTN:       209.42d {+13h 57m 41s}  -12.02d {-12d 01' 14"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.12d {+16h 16m 29s}  -26.43d {-26d 25' 29"}
  MOON_DIST:        55.78 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Source List.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 18:00:36 UT
  NOTICE_TYPE:     Swift-UVOT Processed Source List
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.631d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.571d {-68d 34' 13"} (J2000)
  POINT_ROLL:      258.910d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64312.79 SOD {17:51:52.79} UT,   290.5 [sec] since BAT Trigger Time
  FILTER:          7, U
  BKG_MEAN:        0.522
  N_STARS:         157
  X_OFFSET:        252 [pixels]
  Y_OFFSET:        285 [pixels]
  X_MAX:           1691 [pixels]
  Y_MAX:           1724 [pixels]
  DET_THRESH:      7
  PHOTO_THRESH:    3
  SL_URL:          sw01406589000msufc0290.fits
  SUN_POSTN:       209.42d {+13h 57m 41s}  -12.02d {-12d 01' 14"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.12d {+16h 16m 29s}  -26.43d {-26d 25' 31"}
  MOON_DIST:        55.77 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Source List.  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 18:01:32 UT
  NOTICE_TYPE:     Swift-UVOT Processed Image
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.631d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.571d {-68d 34' 13"} (J2000)
  ROLL:            258.910d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64312.79 SOD {17:51:52.79} UT,   290.5 [sec] since BAT Trigger Time
  FILTER:          7, U
  EXPOSURE_ID:     783021149
  X_OFFSET:        811 [pixels]
  Y_OFFSET:        844 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       971
  Y_GRB_POS:       1004
  BINNING_INDEX:   1
  IM_URL:          sw01406589000msuni0327.fits
  SUN_POSTN:       209.42d {+13h 57m 41s}  -12.02d {-12d 01' 15"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.13d {+16h 16m 31s}  -26.43d {-26d 25' 36"}
  MOON_DIST:        55.77 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Processed Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  COMMENTS:        All 4 attachments are included.  
  

  
• GCN Circular #42425
  V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko, G.Antipov, A.Sankovich, Yu.Tselik, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU), O.Gress, N.Budnev (ISU), C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA), A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory), A.Sosnovskij (CrAO), A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity), D.Buckley (SAAO), R.Rebolo (The Instituto de Astrofisica de Canarias), L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
  MASTER-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) was pointed to the Swift GRB251024.74 (trigger No 1406589,20h 26m 29.26s , -68d 34m 26.4s, R=0.05) errorbox 10 sec after notice time and 73 sec after trigger time at 2025-10-24 17:48:15 UT, with upper limit up to 16.5 mag. Observations started at twilight. The observations began at zenith distance = 38 deg. The sun altitude is -11.1 deg.
  The galactic latitude b = -34 deg., longitude l = 327 deg.
  Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=3022698
  We obtain a following upper limits.

  Tmid-T0  |          Site       |Filt.| Expt. | Limit| Comment
  _________|_____________________|_____|_______|______|________
  
        78 |         MASTER-SAAO |  P\ |    10 | 16.2 |        
        78 |         MASTER-SAAO |   C |    10 | 16.1 |        
       112 |         MASTER-SAAO |  P\ |    20 | 16.5 |        
       112 |         MASTER-SAAO |   C |    20 | 16.3 |        
  

  Filter C is a clear (unfiltred) band.
  The observation and reduction will continue. The message may be cited.
• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 18:00:46 UT
  NOTICE_TYPE:     Swift-XRT Position UPDATE
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  GRB_RA:          306.5974d {+20h 26m 23.37s} (J2000),
                   307.2203d {+20h 28m 52.87s} (current),
                   305.3805d {+20h 21m 31.31s} (1950)
  GRB_DEC:         -68.5723d {-68d 34' 20.2"} (J2000),
                   -68.4860d {-68d 29' 09.5"} (current),
                   -68.7359d {-68d 44' 09.2"} (1950)
  GRB_ERROR:       1.9 [arcsec radius, statistical plus systematic, 90% containment]
  GRB_INTEN:       1.00e-10 [erg/cm2/sec]
  GRB_SIGNIF:      10.00 [sigma]
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64187.00 SOD {17:49:47.00} UT,   164.8 [sec] since BAT Trigger Time
  TAM[0-3]:        100.00 100.00 100.00 100.00
  AMPLIFIER:       1
  WAVEFORM:        31
  SUN_POSTN:       209.42d {+13h 57m 41s}  -12.02d {-12d 01' 14"}
  SUN_DIST:         81.66 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.12d {+16h 16m 29s}  -26.43d {-26d 25' 32"}
  MOON_DIST:        55.76 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.73 [deg] galactic lon,lat of the burst
  ECL_COORDS:      288.81,-47.51 [deg] ecliptic lon,lat of the burst
  COMMENTS:        SWIFT-XRT Coordinates.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  COMMENTS:        This is an Update Notice -- the RA,Dec values herein supersede the previous XRT_POS Notice.  
  COMMENTS:        TAM values, flux and significance fields are not valid.  
  COMMENTS:        This position was automatically generated on the ground using  
  COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
  COMMENTS:        See https://www.swift.ac.uk/sper/docs.php for details.  
  COMMENTS:        This position was enhanced using UVOT field astrometry.  
  COMMENTS:        The probability that this is a serendipitous source in the  
  COMMENTS:        SPER window is 0.58% < P(seren) < 1.1%.  
  

• GCN NOTICE
  

  TITLE:           GCN/SWIFT NOTICE
  NOTICE_DATE:     Fri 24 Oct 25 18:01:19 UT
  NOTICE_TYPE:     Swift-UVOT Image
  TRIGGER_NUM:     1406589,   Seg_Num: 0
  POINT_RA:        306.631d {+20h 26m 31s} (J2000)
  POINT_DEC:       -68.571d {-68d 34' 13"} (J2000)
  ROLL:            258.910d
  IMG_START_DATE:  20972 TJD;   297 DOY;   25/10/24
  IMG_START_TIME:  64312.79 SOD {17:51:52.79} UT,   290.5 [sec] since BAT Trigger Time
  FILTER:          7, U
  EXPOSURE_ID:     783021149
  X_OFFSET:        811 [pixels]
  Y_OFFSET:        844 [pixels]
  WIDTH:           160 [pixels]
  HEIGHT:          160 [pixels]
  X_GRB_POS:       971
  Y_GRB_POS:       1004
  BINNING_INDEX:   1
  IM_URL:          sw01406589000msuni0327.fits
  SUN_POSTN:       209.42d {+13h 57m 41s}  -12.02d {-12d 01' 15"}
  SUN_DIST:         81.67 [deg]   Sun_angle= -6.5 [hr] (East of Sun)
  MOON_POSTN:      244.13d {+16h 16m 31s}  -26.43d {-26d 25' 35"}
  MOON_DIST:        55.77 [deg]
  MOON_ILLUM:      9 [%]
  GAL_COORDS:      326.64,-33.75 [deg] galactic lon,lat of the pointing direction
  ECL_COORDS:      288.83,-47.51 [deg] ecliptic lon,lat of the pointing direction
  COMMENTS:        SWIFT-UVOT Image.  
  COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
  COMMENTS:        The image has 2x2 binning (compression).  
  

  
• GCN Circular #42426
  M. J. Moss (GSFC), S. Dichiara (PSU), R. A. J. Eyles-Ferris (U Leicester), R. Gupta (NASA GSFC), J. A. Kennea (PSU), A. Y. Lien (U Tampa), K. L. Page (U Leicester) and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift Observatory Team:
  At 17:47:02.25 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 251024A (trigger= 1406589). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 306.622, -68.574 which is

     RA(J2000) = 20h 26m 29s
     Dec(J2000) = -68d 34' 25"
  

  with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a complex structure with a duration of about 30 sec. The peak count rate was ~1000 counts/sec (15-350 keV), at ~0 sec after the trigger.
  The XRT began observing the field at 17:49:11.3 UT, 129.1 seconds after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source with an enhanced position: RA, Dec 306.59743, -68.57225 which is equivalent to:

     RA(J2000)  = 20h 26m 23.38s
     Dec(J2000) = -68d 34' 20.1"
  

  with an uncertainty of 1.9 arcseconds (radius, 90% containment). This location is 32 arcseconds from the BAT onboard position, within the BAT error circle. This position may be improved as more data are received; the latest position is available at https://www.swift.ac.uk/sper.
  A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (3.73 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 3 (+2.09/-1.77) x 10^21 cm^-2 (90% confidence).
  UVOT took a finding chart exposure of 150 seconds with the White filter starting 132 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.044.
  Burst Advocate for this burst is M. J. Moss (mikejmoss3 AT gmail.com). Please contact the BA by email if you require additional information regarding Swift followup of this burst. In extremely urgent cases, after trying the Burst Advocate, you can contact the Swift PI by phone (see Swift TOO web site for information: http://www.swift.psu.edu/)
• GCN Circular #42428
  R. Strausbaugh (Eastern Illinois University), A. Cucchiara (NASA) report on behalf of a larger collaboration:
  We observed the Swift GRB 251024A field (Moss et al., GCN 42426) with the LCOGT 1-meter Sinistro instrument at the South African Astronomical Observatory site, on October 24, from 18:18 to 18:50 UT (corresponding to 0.51 to 1.05 hours after the GRB trigger time) with the Bessel I and R filters.
  We performed a series of 3x300s exposures in I-band and R-band. We detect an uncatalogued source in the XRT error region in both bands, which we propose to be the afterglow.
  The following magnitudes are calculated using the USNO-B1.0 catalog as reference:

  R = 21.2 +/- 0.1
  I = 21.2 +/- 0.2
  

  These magnitudes are not corrected for galactic extinction.
• GCN Circular #42430
  A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
  Using 1910 s of XRT Photon Counting mode data and 3 UVOT images for GRB 251024A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 306.59782, -68.57239 which is equivalent to:

  RA (J2000): 20h 26m 23.48s
  Dec (J2000): -68d 34' 20.6"
  

  with an uncertainty of 2.2 arcsec (radius, 90% confidence).
  This position may be improved as more data are received. The latest position can be viewed at https://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177).
  This circular was automatically generated, and is an official product of the Swift-XRT team.
• GCN Circular #42442
  S. Dichiara (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), V. D'Elia (SSDC & INAF-OAR), B. Sbarufatti (INAF-OAB), C. Salvaggio (INAF-OAB), J.A. Kennea (PSU), D.N. Burrows (PSU) and P.A. Evans report on behalf of the Swift-XRT team:
  We have analysed 4.4 ks of XRT data for GRB 251024A, from 113 s to 56.4 ks after the trigger. The data comprise 30 s in Windowed Timing (WT) mode (the first 10 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The late-time light curve (from T0+4.5 ks) is consistent with a constant source of mean count rate 4.5e-01 ct/sec. A power-law fit gives an index of -0.14 (+0.15, -0.14).
  A spectrum formed from the PC mode data can be fitted with an absorbed power-law with a photon spectral index of 2.06 (+0.16, -0.11). The best-fitting absorption column is consistent with the Galactic value of 3.7 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.2 x 10^-11 (3.6 x 10^-11) erg cm^-2 count^-1.
  A summary of the PC-mode spectrum is thus:

  Total column:	     3.7 (+/-2.8) x 10^20 cm^-2
  Galactic foreground: 3.7 x 10^20 cm^-2
  Excess significance: <1.6 sigma
  Photon index:	     2.06 (+0.16, -0.11)
  

  The results of the XRT-team automatic analysis are available at https://www.swift.ac.uk/xrt_products/01406589.
  This circular is an official product of the Swift-XRT team.
• GCN Circular #42444
  T. Sakamoto (AGU), S. D. Barthelmy (GSFC), R. Gupta (GSFC), H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC), M. J. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC), D. Sadaula (GSFC/UMBC) (i.e. the Swift-BAT team):
  Using the data set from T-240 to T+613 sec from the recent telemetry downlink, we report further analysis of BAT GRB 251024A (trigger #1406589) (Moss et al., GCN Circ. 42426). The BAT ground-calculated position is RA, Dec = 306.666, -68.576 deg which is

     RA(J2000)  =  20h 26m 39.7s
     Dec(J2000) = -68d 34' 34.3"
  

  with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 84%.
  The mask-weighted light curve shows a weak pulse structure that starts at ~T+1 s and peaks at ~T+3 s. The main pulse structure ends at ~T+25 s, and there are some tail emissions that last till ~T+100 s. T90 (15-350 keV) is 82.66 +- 23.27 sec (estimated error including systematics).
  The time-averaged spectrum from T+1.16 to T+97.28 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.68 +- 0.30. The fluence in the 15-150 keV band is 6.5 +- 1.2 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+2.16 sec in the 15-150 keV band is 0.5 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
  The results of the batgrbproduct analysis are available at https://swift.gsfc.nasa.gov/results/batgrbcat/BAT_refined_circular/1406589
• GCN Circular #42446
  M. H. Siegel and M. J. Moss (GSFC) report on behalf of the Swift/UVOT team:
  The Swift/UVOT began settled observations of the field of GRB 251024A 132 s after the BAT trigger (Moss et al., GCN Circ. 42426). No optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ. 42430) is detected in the initial UVOT exposures.
  Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are:

  Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
  
  white_FC           132          282          147         >21.0
  u_FC               290          540          246         >19.9
  white              132          591          167         >21.0
  v                  622          641           19         >18.0
  b                  547          567           20         >19.8
  u                  290          540          246         >19.9
  w2                 597          617           20         >19.2
  

  The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.044 in the direction of the burst (Schlegel et al. 1998).