Gamma-ray Burst 221025A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 25 Oct 22 00:58:51 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     688352303
GRB_RA:          118.350d {+07h 53m 24s} (J2000),
                 118.641d {+07h 54m 34s} (current),
                 117.712d {+07h 50m 51s} (1950)
GRB_DEC:          -0.633d {-00d 37' 59"} (J2000),
                  -0.694d {-00d 41' 37"} (current),
                  -0.502d {-00d 30' 08"} (1950)
GRB_ERROR:       10.45 [deg radius, statistical plus systematic]
GRB_INTEN:       452 [cnts/sec]
DATA_SIGNIF:     15.90 [sigma]
INTEG_TIME:      0.512 [sec]
GRB_DATE:        19877 TJD;   298 DOY;   22/10/25
GRB_TIME:        3498.42 SOD {00:58:18.42} UT
GRB_PHI:          70.00 [deg]
GRB_THETA:        30.00 [deg]
DATA_TIME_SCALE: 0.5120 [sec]
HARD_RATIO:      0.17
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      98%  GRB
2nd_MOST_LIKELY:   1%  Generic SGR
DETECTORS:       0,1,1, 1,1,1, 0,0,0, 1,0,0, 0,0,
SUN_POSTN:       209.44d {+13h 57m 45s}  -12.03d {-12d 01' 37"}
SUN_DIST:         90.64 [deg]   Sun_angle= 6.1 [hr] (West of Sun)
MOON_POSTN:      205.01d {+13h 40m 01s}   -8.63d {-08d 38' 03"}
MOON_DIST:        86.30 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      220.71, 13.45 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      120.60,-21.11 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221025040/quicklook/glg_lc_medres34_bn221025040.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 55.03,25.25 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 25 Oct 22 00:59:08 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      58
TRIGGER_NUM:     688352303
GRB_RA:          132.430d {+08h 49m 43s} (J2000),
                 132.739d {+08h 50m 57s} (current),
                 131.753d {+08h 47m 01s} (1950)
GRB_DEC:          +9.890d {+09d 53' 24"} (J2000),
                  +9.804d {+09d 48' 15"} (current),
                 +10.077d {+10d 04' 36"} (1950)
GRB_ERROR:       4.86 [deg radius, statistical only]
DATA_SIGNIF:     18.40 [sigma]
DATA_INTERVAL:   0.512 [sec]
GRB_DATE:        19877 TJD;   298 DOY;   22/10/25
GRB_TIME:        3498.42 SOD {00:58:18.42} UT
GRB_PHI:          63.00 [deg]
GRB_THETA:        47.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4173 (Gnd S/W Version number)
SUN_POSTN:       209.44d {+13h 57m 45s}  -12.03d {-12d 01' 37"}
SUN_DIST:         79.27 [deg]   Sun_angle= 5.1 [hr] (West of Sun)
MOON_POSTN:      205.01d {+13h 40m 02s}   -8.64d {-08d 38' 07"}
MOON_DIST:        74.27 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      217.52, 30.73 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      132.11, -7.57 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221025040/quicklook/glg_lc_medres34_bn221025040.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_688352303.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        Bright hard burst in the GBM.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 25 Oct 22 04:31:57 UT
NOTICE_TYPE:     Fermi-GBM Final Position
RECORD_NUM:      0
TRIGGER_NUM:     688352303
GRB_RA:          128.890d {+08h 35m 34s} (J2000),
                 129.186d {+08h 36m 45s} (current),
                 128.241d {+08h 32m 58s} (1950)
GRB_DEC:          +2.210d {+02d 12' 36"} (J2000),
                  +2.130d {+02d 07' 48"} (current),
                  +2.384d {+02d 23' 01"} (1950)
GRB_ERROR:       6.79 [deg radius, statistical only]
GRB_DATE:        19877 TJD;   298 DOY;   22/10/25
GRB_TIME:        3498.42 SOD {00:58:18.42} UT
GRB_PHI:          59.00 [deg]
GRB_THETA:        39.00 [deg]
E_RANGE:         50.000 - 300.000 [keV]
LOC_ALGORITHM:   415 (Gnd S/W Version number)
SUN_POSTN:       209.58d {+13h 58m 19s}  -12.08d {-12d 04' 40"}
SUN_DIST:         81.07 [deg]   Sun_angle= 5.4 [hr] (West of Sun)
MOON_POSTN:      206.85d {+13h 47m 24s}   -9.52d {-09d 31' 14"}
MOON_DIST:        78.21 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      223.38, 24.07 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      130.72,-15.90 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221025040/quicklook/glg_lc_medres34_bn221025040.gif
LOC_URL:         http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221025040/quicklook/glg_locplot_all_bn221025040.png
COMMENTS:        Fermi-GBM Final Position.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        The LC_URL file should be available by the time this FINAL notice is produced.  
COMMENTS:        This notice has human-in-the-loop processing.

GCN Notice

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Tue 25 Oct 22 08:36:09 UT
NOTICE_TYPE:     Fermi-LAT Offline Position
TRIGGER_NUM:     688352303
GRB_RA:          133.380d {+08h 53m 31s} (J2000),
                 133.690d {+08h 54m 46s} (current),
                 132.700d {+08h 50m 48s} (1950)
GRB_DEC:         +10.990d {+10d 59' 24"} (J2000),
                 +10.903d {+10d 54' 09"} (current),
                 +11.180d {+11d 10' 48"} (1950)
GRB_ERROR:       75.60 [arcmin radius, 90% containment, statistical only]
GRB_DATE:        19877 TJD;   298 DOY;   22/10/25
GRB_TIME:        3498.42 SOD {00:58:18.42} UT
TRIGGER_ID:      0x0
MISC:            0x40000000
SUN_POSTN:       209.74d {+13h 58m 58s}  -12.14d {-12d 08' 11"}
SUN_DIST:         78.95 [deg]   Sun_angle= 5.1 [hr] (West of Sun)
MOON_POSTN:      208.98d {+13h 55m 56s}  -10.53d {-10d 31' 40"}
MOON_DIST:        77.85 [deg]
MOON_ILLUM:      0 [%]
GAL_COORDS:      216.83, 32.05 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      132.71, -6.25 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        Fermi LAT Offline position.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        It is the result of human-in-the-loop processing.  
COMMENTS:        This is a human generated position of a LAT ground detection.
COMMENTS:        This source corresponds to GBM trigger.

GCN Circular #32840
V. Lipunov, V.Kornilov, E.Gorbovskoy, K.Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, D. Vlasenko,
G.Antipov, D.Zimnukhov, V.Senik, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D.Cheryasov, Ya.Kechin (Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra (The Instituto de Astrofisica de Canarias),
D. Buckley (South African Astronomical Observatory),
O.A. Gres, N.M. Budnev (Irkutsk State University, API),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez, A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational State University)
MASTER-Kislovodsk robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) started inspect of the LAT GRB221025.04 (trigger No 688352303,08h 53m 31.20s , +10d 59m 24.0s, R=1.26) errorbox 73 sec after trigger time at 2022-10-25 00:59:31 UT, with upper limit up to 18.8 mag. The observations began at zenith distance = 49 deg. The sun altitude is -29.1 deg.
The galactic latitude b = 33 deg., longitude l = 217 deg.
Real time updated cover map and OT discovered available here: https://master.sai.msu.ru/site/master2/observ.php?id=2133296
We obtain a following upper limits.

Tmid-T0  |      Date Time      |          Site       |             Coord (J2000)          |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________

      78 | 2022-10-25 00:59:31 |   MASTER-Kislovodsk | (08h 48m 26.64s , +10d 04m 09.5s) |   C |    10 | 16.8 |        
     113 | 2022-10-25 00:59:31 |   MASTER-Kislovodsk | (08h 48m 26.64s , +10d 04m 09.2s) |   C |    80 | 17.7 |  Coadd 
      78 | 2022-10-25 00:59:31 |   MASTER-Kislovodsk | (08h 52m 50.67s , +09d 40m 31.3s) |   C |    10 | 16.6 |        
     113 | 2022-10-25 01:00:01 |   MASTER-Kislovodsk | (08h 48m 32.72s , +10d 03m 07.0s) |   C |    20 | 16.5 |        
     114 | 2022-10-25 01:00:01 |   MASTER-Kislovodsk | (08h 52m 56.62s , +09d 39m 27.4s) |   C |    20 | 16.6 |        
     159 | 2022-10-25 01:00:41 |   MASTER-Kislovodsk | (08h 48m 26.80s , +10d 02m 05.3s) |   C |    30 | 17.0 |        
     159 | 2022-10-25 01:00:41 |   MASTER-Kislovodsk | (08h 52m 50.65s , +09d 38m 25.1s) |   C |    30 | 17.4 |        
     214 | 2022-10-25 01:01:31 |   MASTER-Kislovodsk | (08h 48m 32.76s , +10d 02m 05.4s) |   C |    40 | 17.3 |        
     214 | 2022-10-25 01:01:32 |   MASTER-Kislovodsk | (08h 52m 56.63s , +09d 38m 24.8s) |   C |    40 | 17.8 |        
     278 | 2022-10-25 01:02:31 |   MASTER-Kislovodsk | (08h 48m 30.73s , +10d 03m 46.4s) |   C |    50 | 17.5 |        
     278 | 2022-10-25 01:02:31 |   MASTER-Kislovodsk | (08h 52m 54.63s , +09d 40m 05.3s) |   C |    50 | 18.0 |        
     354 | 2022-10-25 01:03:42 |   MASTER-Kislovodsk | (08h 48m 30.83s , +10d 02m 32.6s) |   C |    60 | 17.4 |        
     354 | 2022-10-25 01:03:42 |   MASTER-Kislovodsk | (08h 52m 54.73s , +09d 38m 51.0s) |   C |    60 | 17.7 |        
    1265 | 2022-10-25 01:17:53 |   MASTER-Kislovodsk | (08h 42m 33.57s , +12d 20m 52.2s) |   C |   180 | 18.0 |        
    1265 | 2022-10-25 01:17:53 |   MASTER-Kislovodsk | (08h 47m 01.30s , +11d 57m 15.5s) |   C |   180 | 17.9 |        
    1466 | 2022-10-25 01:21:14 |   MASTER-Kislovodsk | (08h 46m 55.31s , +11d 56m 45.6s) |   C |   180 | 18.1 |        
    1466 | 2022-10-25 01:21:14 |   MASTER-Kislovodsk | (08h 42m 27.46s , +12d 20m 21.1s) |   C |   180 | 18.1 |        
    1667 | 2022-10-25 01:24:34 |   MASTER-Kislovodsk | (08h 42m 27.47s , +12d 21m 25.0s) |   C |   180 | 18.0 |        
    1667 | 2022-10-25 01:24:34 |   MASTER-Kislovodsk | (08h 46m 55.52s , +11d 57m 50.4s) |   C |   180 | 17.8 |        
    1867 | 2022-10-25 01:27:55 |   MASTER-Kislovodsk | (08h 42m 33.31s , +12d 20m 29.2s) |   C |   180 | 17.8 |        
    1867 | 2022-10-25 01:27:55 |   MASTER-Kislovodsk | (08h 47m 01.68s , +11d 56m 55.0s) |   C |   180 | 17.6 |        
    3748 | 2022-10-25 01:59:16 |   MASTER-Kislovodsk | (08h 42m 43.32s , +12d 21m 59.0s) |   C |   180 | 18.5 |        
    3748 | 2022-10-25 01:59:16 |   MASTER-Kislovodsk | (08h 47m 04.36s , +11d 58m 23.2s) |   C |   180 | 18.3 |        
    4194 | 2022-10-25 02:06:42 |   MASTER-Kislovodsk | (08h 42m 34.56s , +12d 22m 29.3s) |   C |   180 | 18.1 |        
    4194 | 2022-10-25 02:06:42 |   MASTER-Kislovodsk | (08h 46m 57.79s , +11d 58m 06.3s) |   C |   180 | 18.8 |        
    5067 | 2022-10-25 02:21:15 |   MASTER-Kislovodsk | (08h 42m 37.61s , +12d 22m 18.4s) |   C |   180 | 18.3 |        
    5067 | 2022-10-25 02:21:15 |   MASTER-Kislovodsk | (08h 47m 02.20s , +11d 57m 59.1s) |   C |   180 | 18.8 |

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

GCN Circular #32843
Arimoto M. (Kanazawa University) Pillera R. (Politecnico and INFN Bari), and Maheso D. (Johannesburg Univ.) report on behalf of the Fermi-LAT team:
At 00:58:18.42 on October, 25, 2022 Fermi-LAT detected high-energy emission from GRB 221025A, GBM trigger 221025041 / 688352303 at 00:58:18.42 UT.
The best LAT on-ground location is found to be
RA, Dec = 133.4, 11.0 (J2000)
with an error radius of 1.3 deg (90 % containment, statistical error only). This was 45 deg from the LAT boresight at the time of the trigger.
The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally correlated with the trigger with high significance.
The 100 MeV - 1 GeV photon flux in the time interval 0-200 s after the GBM trigger is (2.1 +/- 0.6)E-05 ph/cm2/s. The estimated integrated photon index above 100 MeV is -2.3 +/- 0.3. The highest-energy photon is a 1.3 GeV event with 93% probability which is observed 3 seconds after the GBM trigger.
A Swift ToO has been requested for this burst.
The Fermi-LAT point of contact for this burst is Dimakatso Jeannett Maheso (d.j.maheso@gmail.com).
The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.
GCN Circular #32851
J. Wood (NASA/MSFC) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team:
"At 00:58:18 UT on 25 October 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 221025A (trigger 688352303 / 221025040). which was also detected by Fermi-LAT (Arimoto M. et al. 2022, GCN 32843). The Fermi GBM on-ground location is consistent with the Fermi-LAT position.
The on-ground calculated location, using the GBM trigger data, is RA = 128.9, DEC = +2.2 (J2000 degrees, equivalent to 08h 36m, +02d 12'), with an uncertainty of 6.8 degrees (radius, 1-sigma containment, statistical only; there is additionally a systematic error which we have characterized as a core-plus-tail model, with 90% of GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg systematic error. [Connaughton et al. 2015, ApJS, 216, 32]).
The angle from the Fermi LAT boresight is 48.5 degrees.
The GBM light curve consists of a single pulse with a duration (T90) of about 0.4 s (50-300 keV). The time-averaged spectrum from T0+0.0 to T0+0.8 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.4 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 1680 +/- 345 keV.
The event fluence (10-1000 keV) in this time interval is (1.7 +/- 0.1)E-06 erg/cm^2. The 64-ms peak photon flux measured starting from T0+0.3 s in the 10-1000 keV band is 13.3 +/- 0.9 ph/s/cm^2.
The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog: https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support Page: https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular #32853
R. Gopalakrishnan (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a short GRB 221025A which was also detected by Fermi-GBM (Wood et al,. GCN 32851) and Fermi-LAT (Arimoto et al,. GCN 32843).
The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2022-10-25 00:58:18.6 UTC. The measured peak count rate associated with the burst is 904 (+212, -102) counts/s above the background in the combined data of all quadrants, with a total of 313 (+62, -63) counts. The local mean background count rate was 435 (+8, -12) counts/s. Using cumulative rates, we measure a T90 of 0.45 (+0.6, -0.2) s.
It was also detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. Due to the intrinsic 1 s binning of veto data, we cannot reliably estimate a T90 from it.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.
GCN Circular #32865
D. Svinkin, D. Frederiks, A. Ridnaia, A. Lysenko, and T. Cline on behalf of the Konus-Wind team,
A. Goldstein, M. S. Briggs, C. Wilson-Hodge, and E. Burns on behalf of the Fermi GBM team,
E. Bozzo and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, report:
The short-duration GRB 221025A (Fermi-LAT detection: Arimoto et al., GCN Circ. 32843; Fermi-GBM detection: Wood and Meegan, GCN Circ. 32851; AstroSat-CZTI detection: Gopalakrishnan et al., GCN Circ. 32853) was detected by Fermi (GBM trigger 688352303), INTEGRAL (SPI-ACS), Konus-Wind, AstroSat (CZTI), and GECAM-B (trigger tn221025_005818_fb) at about 3498 s UT (00:58:18).
We have triangulated it to a preliminary, 3 sigma error box whose coordinates are:
```
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   134.373 (08h 57m 29s) +13.068 (+13d 04' 07")
  Corners:
   133.601 (08h 54m 24s) +10.772 (+10d 46' 20")
   133.259 (08h 53m 02s) +10.806 (+10d 48' 20")
   135.172 (09h 00m 41s) +15.363 (+15d 21' 46")
   135.522 (09h 02m 05s) +15.330 (+15d 19' 48")
  ---------------------------------------------
```
The error box area is 1.6 sq. deg, and its maximum dimension is 5.03 deg (the minimum one is 19.44 arcmin). The Sun distance was 78 deg.
This localization may be improved.
The IPN localization is consistent with, but reduces the area of, the Fermi-GBM final localization (glg_healpix_all_bn221025040_v00).
A triangulation map and HEALPix FITS file are posted at http://www.ioffe.ru/LEA/GRBs/GRB221025_T03498/IPN/
The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.

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Jochen Greiner, last update: 27-Oct-2022 [Disclaimer]