- GCN NOTICE
TITLE: GCN/FERMI NOTICE
NOTICE_DATE: Wed 29 Nov 23 19:10:47 UT
NOTICE_TYPE: Fermi-GBM Flight Position
RECORD_NUM: 46
TRIGGER_NUM: 722977823
GRB_RA: 350.683d {+23h 22m 44s} (J2000),
351.325d {+23h 25m 18s} (current),
349.215d {+23h 16m 52s} (1950)
GRB_DEC: -86.517d {-86d 31' 00"} (J2000),
-86.385d {-86d 23' 06"} (current),
-86.791d {-86d 47' 26"} (1950)
GRB_ERROR: 3.38 [deg radius, statistical plus systematic]
GRB_INTEN: 6629 [cnts/sec]
DATA_SIGNIF: 322.70 [sigma]
INTEG_TIME: 1.024 [sec]
GRB_DATE: 20277 TJD; 333 DOY; 23/11/29
GRB_TIME: 69018.11 SOD {19:10:18.11} UT
GRB_PHI: 281.00 [deg]
GRB_THETA: 45.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO: 0.31
LOC_ALGORITHM: 3 (version number of)
MOST_LIKELY: 96% GRB
2nd_MOST_LIKELY: 3% Generic Transient
DETECTORS: 0,0,0, 1,0,0, 0,1,1, 0,0,0, 0,0,
SUN_POSTN: 245.49d {+16h 21m 58s} -21.52d {-21d 31' 29"}
SUN_DIST: 69.50 [deg] Sun_angle= -7.1 [hr] (East of Sun)
MOON_POSTN: 97.45d {+06h 29m 47s} +28.18d {+28d 10' 51"}
MOON_DIST: 119.13 [deg]
MOON_ILLUM: 94 [%]
GAL_COORDS: 304.45,-30.35 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 278.40,-65.77 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_lc_medres34_bn231129799.gif
COMMENTS: Fermi-GBM Flight-calculated Coordinates.
COMMENTS: This trigger occurred at longitude,latitude = 134.23,-6.13 [deg].
COMMENTS: The LC_URL file will not be created until ~15 min after the trigger.
- GCN NOTICE
TITLE: GCN/FERMI NOTICE
NOTICE_DATE: Wed 29 Nov 23 19:10:57 UT
NOTICE_TYPE: Fermi-GBM Flight Position
RECORD_NUM: 59
TRIGGER_NUM: 722977823
GRB_RA: 345.833d {+23h 03m 20s} (J2000),
346.363d {+23h 05m 27s} (current),
344.685d {+22h 58m 44s} (1950)
GRB_DEC: -81.933d {-81d 55' 59"} (J2000),
-81.804d {-81d 48' 14"} (current),
-82.203d {-82d 12' 08"} (1950)
GRB_ERROR: 3.42 [deg radius, statistical plus systematic]
GRB_INTEN: 5677 [cnts/sec]
DATA_SIGNIF: 563.20 [sigma]
INTEG_TIME: 4.096 [sec]
GRB_DATE: 20277 TJD; 333 DOY; 23/11/29
GRB_TIME: 69018.11 SOD {19:10:18.11} UT
GRB_PHI: 281.00 [deg]
GRB_THETA: 50.00 [deg]
DATA_TIME_SCALE: 4.0960 [sec]
HARD_RATIO: 0.49
LOC_ALGORITHM: 3 (version number of)
MOST_LIKELY: 95% GRB
2nd_MOST_LIKELY: 4% Generic Transient
DETECTORS: 0,0,0, 1,0,0, 0,1,1, 0,0,0, 0,0,
SUN_POSTN: 245.49d {+16h 21m 58s} -21.52d {-21d 31' 29"}
SUN_DIST: 70.24 [deg] Sun_angle= -6.7 [hr] (East of Sun)
MOON_POSTN: 97.45d {+06h 29m 48s} +28.18d {+28d 10' 50"}
MOON_DIST: 120.84 [deg]
MOON_ILLUM: 94 [%]
GAL_COORDS: 307.36,-34.24 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 287.74,-63.48 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_lc_medres34_bn231129799.gif
COMMENTS: Fermi-GBM Flight-calculated Coordinates.
COMMENTS: This trigger occurred at longitude,latitude = 134.23,-6.13 [deg].
COMMENTS: The LC_URL file will not be created until ~15 min after the trigger.
- GCN NOTICE
TITLE: GCN/FERMI NOTICE
NOTICE_DATE: Wed 29 Nov 23 19:11:06 UT
NOTICE_TYPE: Fermi-GBM Ground Position
RECORD_NUM: 58
TRIGGER_NUM: 722977823
GRB_RA: 2.460d {+00h 09m 50s} (J2000),
2.723d {+00h 10m 53s} (current),
1.898d {+00h 07m 36s} (1950)
GRB_DEC: -82.190d {-82d 11' 23"} (J2000),
-82.057d {-82d 03' 24"} (current),
-82.468d {-82d 28' 05"} (1950)
GRB_ERROR: 1.00 [deg radius, statistical only]
DATA_SIGNIF: 610.20 [sigma]
DATA_INTERVAL: 2.048 [sec]
GRB_DATE: 20277 TJD; 333 DOY; 23/11/29
GRB_TIME: 69018.11 SOD {19:10:18.11} UT
GRB_PHI: 278.00 [deg]
GRB_THETA: 49.00 [deg]
E_RANGE: 44.032 - 279.965 [keV]
LOC_ALGORITHM: 4173 (Gnd S/W Version number)
SUN_POSTN: 245.49d {+16h 21m 58s} -21.52d {-21d 31' 29"}
SUN_DIST: 72.27 [deg] Sun_angle= -7.8 [hr] (East of Sun)
MOON_POSTN: 97.45d {+06h 29m 48s} +28.18d {+28d 10' 50"}
MOON_DIST: 118.54 [deg]
MOON_ILLUM: 94 [%]
GAL_COORDS: 304.64,-34.80 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 289.25,-65.68 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_lc_medres34_bn231129799.gif
POS_MAP_URL: http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_722977823.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: Wed 29 Nov 23 19:19:37 UT
NOTICE_TYPE: Fermi-GBM Final Position
RECORD_NUM: 0
TRIGGER_NUM: 722977823
GRB_RA: 2.040d {+00h 08m 10s} (J2000),
2.313d {+00h 09m 15s} (current),
1.458d {+00h 05m 50s} (1950)
GRB_DEC: -81.530d {-81d 31' 47"} (J2000),
-81.397d {-81d 23' 48"} (current),
-81.808d {-81d 48' 29"} (1950)
GRB_ERROR: 1.00 [deg radius, statistical only]
GRB_DATE: 20277 TJD; 333 DOY; 23/11/29
GRB_TIME: 69018.11 SOD {19:10:18.11} UT
GRB_PHI: 278.00 [deg]
GRB_THETA: 50.00 [deg]
E_RANGE: 44.032 - 279.965 [keV]
LOC_ALGORITHM: 41731 (Gnd S/W Version number)
SUN_POSTN: 245.50d {+16h 21m 59s} -21.53d {-21d 31' 32"}
SUN_DIST: 72.54 [deg] Sun_angle= -7.8 [hr] (East of Sun)
MOON_POSTN: 97.54d {+06h 30m 08s} +28.18d {+28d 10' 43"}
MOON_DIST: 118.61 [deg]
MOON_ILLUM: 94 [%]
GAL_COORDS: 304.88,-35.43 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 290.74,-65.44 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_lc_medres34_bn231129799.gif
LOC_URL: http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_locplot_all_bn231129799.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 was generated completely by automated pipeline processing.
COMMENTS: In the LAT Field-of-view.
COMMENTS: Bright hard burst in the GBM.
COMMENTS: This is likely a Long GRB.
COMMENTS:
COMMENTS: NOTE: This GBM event is temporally(3.0<100sec) coincident with the CALET_GBM event (trignum=1385320118).
- GCN Circular #35217
The Fermi GBM team reports the detection of a likely LONG GRB
At 19:10:18 UT on 29 Nov 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231129C (trigger 722977823.114938 / 231129799).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 2.0, Dec = -81.5 (J2000 degrees, equivalent to J2000 00h 08m, -81d 30'), with a statistical uncertainty of 1.0 degrees.
The angle from the Fermi LAT boresight is 50.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_skymap_all_bn231129799.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_healpix_all_bn231129799.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_lc_medres34_bn231129799.gif
- GCN Circular #35221
V. Sharma (NASA-GSFC/UMBC) and O. Roberts (NASA-MSFC/USRA) reports on behalf of the Fermi GBM Team:
"At 19:10:18.11 UT on 29 November 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231129C (trigger 722977823/231129799).
The GBM light curve consists of a very bright pulse, with a duration of about 15 seconds. This event, a likely, long GRB, is very bright and follow-up across all wavelengths is encouraged.
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 2.04, Dec = -81.53 (J2000 degrees, equivalent to J2000 00h 08m, -81d 32'), with a statistical uncertainty of 1.00 degree (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 50 degrees.
A full science circular is forthcoming.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_skymap_all_bn231129799.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_healpix_all_bn231129799.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231129799/quicklook/glg_lc_medres34_bn231129799.gif."
- GCN Circular #35222
T. Preis, B. Biltzinger, J. Burgess & J. Greiner (all MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
at 19:10:18 on 29 Nov. 2023 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).
The best-fit position (1 sigma statistical errors) is:
RA(2000.0) = 7.8+/-1.7 deg
Decl.(2000.0) = -81.3+/-0.3 deg
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB231129799/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB231129799/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB231129799/json
- GCN Circular #35223
Y. Kawakubo (LSU),
H. Negoro, M. Nakajima, K. Kobayashi, M. Tanaka, Y. Soejima, Y. Kudo (Nihon U.),
T. Mihara, T. Kawamuro, S. Yamada, T. Tamagawa, N. Kawai, M. Matsuoka (RIKEN),
T. Sakamoto, M. Serino, S. Sugita, H. Hiramatsu, H. Nishikawa, A. Yoshida (AGU),
Y. Tsuboi, S. Urabe, S. Nawa, N. Nemoto, E.Goto (Chuo U.),
M. Shidatsu (Ehime U.),
I. Takahashi, M. Niwano, S. Sato, N. Higuchi, Y. Yatsu (Tokyo Tech),
S. Nakahira, S. Ueno, H. Tomida, M. Ishikawa, S. Ogawa, T. Kurihara (JAXA),
Y. Ueda, K. Setoguchi, T. Yoshitake, Y. Nakatani, Y. Okada (Kyoto U.),
M. Yamauchi, Y. Hagiwara, Y. Umeki, Y. Otsuki (Miyazaki U.),
K. Yamaoka (Nagoya U.),
M. Sugizaki (NAOC),
W. Iwakiri (Chiba U.)
report on behalf of the MAXI team:
The MAXI/GSC nova alert system triggered a bright uncatalogued X-ray transient
source at 2023/11/29 19:10:18 UT.
Assuming that the source flux was constant over the transit,
we obtain the source position at
(R.A., Dec) = (11.910 deg, -81.636 deg) = (00 47 38, -81 38 09) (J2000)
with a statistical 90% C.L. elliptical error region
with long and short radii of 0.09 deg and 0.07 deg, respectively.
The roll angle of long axis from the north direction is 90.0 deg counterclockwise.
There is an additional systematic uncertainty of 0.1 deg (90% containment radius).
The X-ray flux averaged over the scan was 1355 +- 82 mCrab
(4.0-10.0keV, 1 sigma error).
Without assumptions on the source constancy, we obtain a rectangular error
box for the transient source with the following corners:
(R.A., Dec) = (12.351, -81.744) deg = (00 49 24, -81 44 38) (J2000)
(R.A., Dec) = (11.353, -81.663) deg = (00 45 24, -81 39 46) (J2000)
(R.A., Dec) = (12.374, -81.394) deg = (00 49 29, -81 23 38) (J2000)
(R.A., Dec) = (13.350, -81.472) deg = (00 53 23, -81 28 19) (J2000)
There was no significant excess flux in the previous transit at 17:37 UT
with an upper limit of 20 mCrab for each.
- GCN Circular #35225
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a series of observations, tiled on the sky, of the
Fermi/GBM GRB 231129C. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00117
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the Fermi/GBM event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
- GCN Circular #35226
I observed the field of GRB 231129C (Fermi GBM Team, GCN Circ. 35217)
near the MAXI (GCN Circ. 35223) sky region using remote telescope T72
(0.51-m f/6.8 Corrected Dall-Kirkham + CCD) of iTelescope.Net in Deep
Sky Chile at Rio Hurtado Valley, Chile. 9 images (with exposures 300
seconds, BINx1) were obtained with Ic filter with midtime 02:27 UT. I
detected an uncataloged source with position 00 49 17.780 -81 29 45.83
and measured its brightness near +18 mag. Magnitude was not corrected
for Galactic extinction. I am guessing this is an optical afterglow of
GRB 231129C. Now it is AT 2023yph
https://www.wis-tns.org/object/2023yph
F. D. Romanov (AAVSO).
- GCN Circular #35227
V. Sharma (NASA-GSFC/UMBC), C. Fletcher (USRA) and C. Meegan (UAH) report on behalf of the Fermi Gamma-ray Burst Monitor Team:
"At 19:10:18.11 UT on 29 November 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231129C (trigger 722977823/231129799), which was also detected by MAXI/GSC (Y. Kawakubo et al. 2023, GCN 35223). The Fermi GBM Final Real-time Localization is reported (GCN 35221, GCN 35217).
The angle from the Fermi LAT boresight at the GBM trigger time is 50 degrees.
The GBM light curve shows a very bright, single pulse starting from about T0+0 s to T0+15 s. The calculated duration (T90) is about 6 s (50-300 keV). The time-averaged spectrum from T0+0 s to T0+7 s can be fit by a Band function with Epeak = 215 +/- 2 keV, alpha = -0.11 +/- 0.01, and beta = -2.79 +/- 0.03.
The event fluence (10-1000 keV) in this time interval is (8.41 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+1.8 s in the 10-1000 keV band is 102 +/- 1 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 #35228
Y. Shimizu (Kanagawa U), A. Yoshida, T. Sakamoto, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA),
Y. Asaoka (ICRR), S. Torii, Y. Akaike, K. Kobayashi (Waseda U),
T. Tamura (Kanagawa U), N. Cannady (GSFC/UMBC),
M. L. Cherry (LSU), S. Ricciarini (U of Florence),
P. S. Marrocchesi (U of Siena),
and the CALET collaboration:
The long GRB 231129C (Fermi GBM Final Real-time Localization: Fermi GBM team,
GCN Circ. 35217; Fermi GBM detection: Sharma at al., GCN Circ. 35221; BALROG
localization: Preis et al., GCN Circ 35222; MAXI/GSC detection: Kawakubo et al.,
GCN Circ. 35223) triggered the CALET Gamma-ray Burst Monitor (CGBM) at
19:10:15.03 UTC on 29 November 2023
(http://cgbm.calet.jp/cgbm_trigger/flight/1385320118/index.html).
The burst signal was seen by all CGBM detectors.
The burst light curve shows a single pulse that starts
at T+3.1 sec, peaks at T+4.7 sec, and ends at T+8.9 sec.
The T90 and T50 durations measured by the SGM data are 4.7 +/- 0.4 sec
and 2.2 +/- 0.2 sec (40-1000 keV), respectively.
The ground-processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1385320118/index.html
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at Waseda University.
- GCN Circular #35229
TITLE: GCN CIRCULAR
NUMBER: 35229
SUBJECT: GRB 231129C: iTelescope OT retraction
DATE: 23/11/30 07:25:40 GMT
FROM: Filipp Dmitrievich Romanov at Amateur astronomer
Retraction of GCN #35226. I did not have access to a computer to check
in time that this object was a star with a high proper motion. I
initially compared my images with archival images from the DSS Plate
Finder, but now I have determined that AT 2023yph is a star
#4631003097698452224 from the Gaia DR3.
- GCN Circular #35230
G. Waratkar (IITB), P. K. Navaneeth (IUCAA), 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 an extremely bright long-duration GRB 231129C which was also detected by Fermi-GBM (Fermi GBM team, GCN Circ. 35217), MAXI/GSC (Kawakubo et al., GCN Circ. 35223), and CALET (Shimizu et al., GCN Circ. 35228).
The source was clearly detected in the CZT detectors in the 20-200 keV energy range. Based on the orientation of the CZTI, the burst saturated two quadrants (A, B out of four). We report two versions of our analysis of CZT data: one from two unsaturated quadrants (C, D), and the other for all four quadrants by including unsaturated data segments from A, B.
For the two unsaturated quadrants C and D, the light curve peaks at 2023-11-29 19:10:18 UTC. The measured peak count rate associated with the burst is 1189 (+237, -8) counts/s above the background in the combined CD data, with a total of 3838 (+150, -144) counts. The local mean background count rate was 155.1 (+3.7, -5.9) counts/s. Using cumulative rates, we measure a T90 of 5.1 (+0.2, -0.2) s in these two quadrants.
Using unsaturated data segments from all four quadrants, we report that burst duration was 6.7 (+0.2, -0.2) s. We also report a minimum peak count rate of 4164.2 (+328.9, -329.3) counts/s at a local mean background count rate of 334.8 (+6.7, -7.4) count/s, with a total of at least 8061 (+195, -236) counts. In the preliminary analysis, we find 1362 Compton events associated with this event in all four quadrants.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-11-29 19:10:18.69 UTC. The measured peak count rate is 4408 (+125, -126) counts/s above the background in the combined Veto data of all quadrants, with a total of 18860 (+406, - 410) counts. The local mean background count rate was 1511.3 (+6.5, -7.7) counts/s. We measure a T90 of 5.5 (+0.2, -0.2) s from the cumulative Veto light curve.
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.
CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb
- GCN Circular #35231
GRB 231129C: GECAM-B detection of a bright burst
Chao Zheng, Shaolin Xiong, report on behalf of the GECAM team:
GECAM-B was triggered in-flight by a likely long burst, GRB 231129C,
at 2023-11-29T19:10:18.200 UTC, which was also observed by
Fermi/GBM (Fermi/GBM team, GCN 35217 & 35227) and MAXI/GSC
(Y. Kawakubo et al., GCN 35223) and CALET (Y. Shimizu et al., GCN 35228)
and AstroSat (G. Waratkar et al., GCN 35230).
According to the realtime alert data of GECAM-B, this burst mainly consists
of a bright pulse with a total duration (T90) of about ~15 sec (20-1000 keV).
The GECAM light curve could be found here:
http://twiki.ihep.ac.cn/pub/HXMT/GRBList/GRB231129C_LC.png
GECAM location is consistent with that of MAXI/GSC within the error.
We note that these results are based on realtime alert data and thus very preliminary.
Refined analysis will be reported later.
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor
(GECAM) mission originally consists of two microsatellites (GECAM-A and GECAM-B)
launched in Dec. 2020. As the third member of GECAM constellation,
GECAM-C was launched onboard SATech-01 experimental satellite in July 2022.
GECAM mission is funded by the Chinese Academy of Sciences (CAS).
- GCN Circular #35234
J. D. Gropp (PSU), S. Dichiara (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J.A. Kennea (PSU) and P.A.
Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the
Fermi/GBM-detected burst GRB 231129C in a series of observations tiled
on the sky. The total exposure time is 1.5 ks, distributed over 4
tiles; the maximum exposure at a single sky location was 633 s. The
data were collected between T0+19.3 ks and T0+35.4 ks, and are entirely
in Photon Counting (PC) mode.
One uncatalogued X-ray source has been detected, it is below the RASS
limit and shows no definitive signs of fading. Therefore, at the
present time we cannot confirm this as the afterglow. Details of this
source are given below:
Source 2:
RA (J2000.0): 11.1769 = 00:44:42.45
Dec (J2000.0): -81.9936 = -81:59:37.0
Error: 9.5 arcsec (radius, 90% conf.)
Count-rate: 0.0208 [+0.0113, -0.0084] ct s^-1
Distance: 1341 arcsec from Fermi/GBM position.
Flux: (8.6 [+4.7, -3.5])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)
A catalogued source was also detected.
The results of the XRT-team automatic analysis of the tiled XRT
observations, including a position-specific upper limit calculator, are
available at https://www.swift.ac.uk/xrt_products/TILED_GRB00117.
This circular is an official product of the Swift-XRT team.
- GCN Circular #35235
C.C. Cheung, M. Kerr, J. E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A.
Wilson-Hodge (MSFC), and M.S. Briggs (UAH) report:
The Glowbug gamma-ray telescope [1,2], operating on the International Space
Station, reports the detection of GRB 231129C, which was also detected by
Fermi/GBM, MAXI/GSC, CALET, AstroSat/CZTI, and GECAM-B (GCN 35217, 35221, 35222, 35223, 35227, 35228, 35230, 35231).
Using an adaptive window with a resolution of 32-ms, the burst onset is det=
ermined to be 2023-11-29 19:10:16.184 with a duration of 8.19 s and a total
significance of about 116 sigma. The light curve comprises an initial tri=
ple-peaked structure from T0 to ~T0+4s, followed by fading emission.
Using a standard power-law function with an exponential high-energy cutoff =
[3] to model the emission over this duration results in a photon index dN/d=
E~E^x of x=3D1.4 and a cutoff energy ("Epeak") of 349 keV. The modeled 10-=
10000 keV fluence is 1.5e-05 erg/cm^2.
The analysis results presented here are preliminary and use a response func=
tion that lacks a detailed characterization of the surrounding passive stru=
cture of the ISS.
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost ga=
mma-ray transient telescopes developed, built, and operated by the U.S. Nav=
al Research Laboratory (NRL) with support from the University of Alabama in=
Huntsville, USRA, and NASA MSFC. It was launched on 2023 March 15 aboard =
the Department of Defense Space Test Program=E2=80=99s STP-H9 to the ISS. =
The detector comprises 12 large-area (15 cm x 15 cm) CsI:Tl panels covering=
the surface of a half cube, and two hexagonal (5-cm diameter, 10-cm length=
) CLLB scintillators, giving it a large field of view (instantaneous FoV ~2=
/3 sky) over a wide energy band of 50 keV to >2 MeV.
[1] Grove, J.E. et al. 2020, Proc. Yamada Conf. LXXI, arXiv:2009.11959
[2] Woolf, R.S. et al. 2022, Proc. SPIE, 12181, id. 121811O
[3] Goldstein, A. et al. 2020, ApJ 895, 40, arXiv :1909.03006
Distribution Statement A: Approved for public release. Distribution is unl=
imited.
- GCN Circular #35236
M. Dafcikova, J. Ripa (Masaryk U.), A. Pal (Konkoly Observatory), N. Werner=
(Masaryk U.), M. Ohno, H. Takahashi (Hiroshima U.), L. Meszaros, B. Csak (=
Konkoly Observatory), N. Husarikova, F. Munz , M. Topinka, M. Kolar, L. Sza=
kszonova, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Po=
valac (Brno U. of Technology), J. Hudec, J. Kapus, M. Frajt (Spacemanic s.r=
.o), R. Laszlo, M. Koleda (Needronix s.r.o), M. Smelko, P. Hanak, P. Lipovs=
ky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.)=
, Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. B=
ozoki (Eotvos U.), G. Dalya (Eotvos U.), yyT. Enoto (Kyoto U.), Zs. Frei (E=
otvos U.), G. Friss (Eotvos U.), Y. Fukazawa, K. Hirose (Hiroshima U.), S. =
Hisadomi (Nagoya U.), Y. Ichinohe (Rikkyo U.), K. Kapas (Eotvos U.), L. L. =
Kiss (Konkoly Observatory), T. Mizuno (Hiroshima U.), K. Nakazawa (Nagoya =
U.), H. Odaka (Univ of Tokyo), J. Takatsy (Eotvos U.), K. Torigoe (Hiroshim=
a U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Toky=
o), T. Kano (U. Michigan) -- the GRBAlpha collaboration.
The bright long-duration GRB 231129C (Fermi/GBM detection: GCN 35217; MAXI/=
GSC detection: GCN 35223; CALET/CGBM detection: GCN 35228; AstroSat detecti=
on: GCN 35230; GECAM-B detection: GCN 35231; INTEGRAL/SPI-ACS peak detectio=
n at 2023-11-29 ~19:10:19 UT) was observed by the GRBAlpha 1U CubeSat (Pal =
et al. 2023, A&A, 677, 40; arXiv:2302.10048).
The detection was confirmed at the peak time 2023-11-29 19:10:19 UTC. The T=
90 duration measured by GRBAlpha is 6 s and the overall significance during=
T90 reaches 93 sigma.
The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB231129C_GCN.pdf
All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/he=
a/GRBAlpha/=20
GRBAlpha, launched on 2021 March 22, is a demonstration mission for a futur=
e CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GR=
BAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM ar=
ray, covering the energy range from ~50 keV to ~1000 keV. To increase the d=
uty cycle and the downlink rate, the upgrade of the on-board data acquisiti=
on software stack is in progress. The ground segment is also supported by t=
he radio amateur community and it takes advantage of the SatNOGS network fo=
r increased data downlink volume.
- GCN Circular #35238
M. Arimoto (Kanazawa University), N. Omodei (Stanford University), D. Kocevski (NASA/MSFC) report on behalf of the Fermi-LAT Collaboration:
On November 29, 2023 Fermi-LAT detected high-energy emission from GRB 231129C, which was also detected by Fermi-GBM (trigger 722977823 / 231129799, GCN 35221), MAXI-GSC (GCN 35223), CALET (GCN 35228), AstroSat (GCN 35230), GECAM-B (GCN 3523), Glowbug (GCN 35235), and GRBAlpha (GCN 35236).
The best LAT on-ground location is found to be R.A., Dec. = 9.1, -81.9 (degrees, J2000) with an error radius of 0.7 deg (90% containment, statistical error only).
This was 49 deg from the LAT boresight at the time of the GBM trigger:
T0 = 19:10:18.11 UT.
The data from the Fermi-LAT show a significant increase in the event rate after the GBM trigger that is spatially correlated with the GBM emission with high significance. The photon flux above 100 MeV in the time interval 0-200 s after the GBM trigger is (3.2 +/- 0.9)E-4 ph/cm2/s.
The estimated photon index above 100 MeV is -2.4 +/- 0.4. The highest-energy photon is a 0.7 GeV event which is observed 4 seconds after the GBM trigger.
The Fermi-LAT point of contact for this burst is Feraol Fana Dirirsa (ffdirirsa@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 #35240
G.Antipov, V.Lipunov, E.Gorbovskoy (Lomonosov MSU), D.Buckley (SAAO),
D.Svinkin (Ioffe Institute, Konus-Wind),
Ya.Kechin, K.Zhirkov, A.Kuznetsov, D.Vlasenko, P.Balanutsa, Yu.Tselik, N.Tiurina, I.Gorbunov, V.Vladimirov,
D.Zimnukhov, V.Senik, A.Yudin,A.Chasovnikov, D.Cheryasov, A.Sosnovskij (Lomonosov MSU,SAI,PhysicsDepartment),
O.A. Gres, N.M. Budnev (Irkutsk State University, API),
C.Francile. F. Podesta, R.Podesta (Observatorio Astronomico Felix Aguilar OAFA),
R. Rebolo, M. Serra(The Instituto de Astrofisica de Canarias),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity)
MASTER Global robotic net (http://observ.pereplet.ru Lipunov et al.,2010,Advances in Astronomy,2010,30L)
started GECAM-B (Ttrigger=2023-11-29 19:10:18.2, Tnotice_socket=2023-11-29 19:11:45.56 Zheng et al. GCN 35231) and
Fermi very bright GRB 231129C (Ttrigger=2023-11-29 19:10:18.11, Tnotice_socket=2023-11-29 19:19:40.72 Sharma et al. GCN 35227,
GCN 35238, also MAXI-GSC (GCN 35223), CALET (GCN 35228), AstroSat (GCN 35230))
55 sec after notice time and 90 sec after trigger time at 2023-11-29 19:11:48 UT (Lipunov et al. GCN 35216)
by MASTER-SAAO.
There is OT source at R.A.,Dec(2000)=00:44:37.97 -81:59:48.75 +-4" with m_OT~17.6 at maximum (unfiltered) at first images with decay inside Swift XRT error-box (Evans et al. GCN 35225, Gropp et al. GCN 35234)
Reduction will be continued.
- GCN Circular #35242
James DeLaunay (PSU), Aaron Tohuvavohu (U Toronto), Samuele Ronchini (PSU), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:
Swift/BAT did not localize GRB 231129C onboard (T0: 2023-11-29T19:10:15.02 UTC, CALET trig 1385320118 / GCN 35223 Fermi GBM trig 722460326 / GCN 35221, GECAM trig 238 / GCN 35231, MAXI-GSC GCN 35223, AstroSat GCN 35230, Glowbug GCN 35235, GRBAlpha GCN 35236, Fermi LAT GCN 35238)
The Fermi notice, distributed in near real-time, triggered the Swift Mission Operations Center operated Gamma-ray Urgent Archiver for Novel Opportunities (GUANO; Tohuvavohu et al. 2020, ApJ, 900, 1).
Upon trigger by this notice, GUANO sent a command to the Swift Burst Alert Telescope (BAT) to save 90 seconds of BAT event-mode data from [-50,+150] seconds around the time of the burst. All the requested event mode data was delivered to the ground.
The BAT likelihood search, NITRATES (DeLaunay + Tohuvavohu 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 92.6 in a 4.096 s analysis time bin, starting at T0 + 3.072 s.
NITRATES results are consistent with a burst coming from outside the FOV, with DeltaLLHOut of -477.
See Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretation of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.
A preliminary localization of this GRB was performed, finding a best fit position of
RA, Dec = 301.3, -80.4 deg
With a roughly circular 90% error radius of 11.1 deg
Calibration of systematics for localizations outside the coded field of view is not yet complete.
GUANO is a fully autonomous, extremely low latency, spacecraft commanding pipeline designed for targeted recovery of BAT event mode data around the times of compelling astrophysical events to enable more sensitive GRB searches.
A live reporting of Swift/BAT event data recovered by GUANO can be found at: https://www.swift.psu.edu/guano/
- GCN Circular #35244
G. Panebianco (Univ. Bologna - INAF/OAS Bologna), A. Bulgarelli (INAF/OAS Bologna),
C. Pittori, F. Verrecchia (SSDC, and INAF/OAR),
M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata),
A. Argan, M. Cardillo, C. Casentini, Y. Evangelista, L. Foffano, G. Piano (INAF/IAPS),
L. Baroncelli, A. Ciabattoni, A. Di Piano, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna),
F. Lucarelli (SSDC, and INAF/OAR), M. Marisaldi (INAF/OAS-Bologna, and Bergen University),
M. Pilia, A. Trois (INAF/OA-Cagliari),
F. Longo (Univ. Trieste, and INFN Trieste), A. Ursi (ASI and INAF/IAPS),
I. Donnarumma, E. Menegoni (ASI), A. Giuliani (INAF/IASF-Mi),
P.W. Cattaneo (INFN Pavia), F. Cutrona (Univ. Milano Bicocca) and P. Tempesta (TeleSpazio)
report on behalf of the AGILE Team:
The AGILE satellite detected the bright and long GRB 231129C at T0 = 2023-11-29 19:10:18 s (UTC),
reported by Fermi (GCNs #35217, #35221, #35227, #35238), BALROG (GCN #35222),
MAXI/GSC (GCN #35223), Swift (GCNs #35225, #35234, #35242), CALET (GCN #35228),
AstroSAT CZTI (GCN #35230), GECAM-B (GCN #35231), Glowbug (GCN #35235),
GRBAlpha (GCN #35236), MASTER OT (#35240).
The burst is clearly visible in the AGILE scientific ratemeters of the
MiniCALorimeter (MCAL; 0.4-100 MeV), and AntiCoincidence (AC; 50-200 keV)
detectors. The pulse lasted about 10 s and it released a total number
of 7648 counts in the MCAL detector (above a background rate of 525 Hz)
and 49403 counts in the AC-Top detector (above a background rate of 2900 Hz).
The AGILE ratemeters light curves can be found at
http://www.agilescienceapp.it/notices/GRB231129C_AGILE_RM_ND.png .
At the detection time the GRB location was occulted by the Earth for the AGILE GRID instrument.
Additional analysis of AGILE data is in progress. Automatic MCAL GRB alert Notices
can be found at: https://gcn.gsfc.nasa.gov/agile_mcal.html
- GCN Circular #35249
Hank Corbett (University of North Carolina), Kendall Ackley (University of Warwick), Daniel E. Reichart (UNC), Joshua B. Haislip (UNC), Vladimir V. Kouprianov (UNC), Megan Dubay (UNC)
We obtained 2x300s unfiltered exposures of the 90% error region of the MAXI/GSC X-ray transient (Kawakubo et al. GCN 35223) with the 0.8-m PROMPT-7 telescope. Exposures began at 2023-11-30 00:53 UT. Relative to images of the field 24-hours later, we do not detect any new sources within the MAXI/GSC error region with an upper limit of 21.9 calibrated to g-band reference stars from the ATLAS reference catalog (Tonry 2018).
We also observed the position of the MASTER OT detection (Antipov et al, GCN 35240) in a series of unfiltered 6x200s exposures beginning at 2023-12-01 01:56 UT, and do not detect the transient in the stacked image to an upper limit of 22.5. The field also includes the 90% error circle for the Swift XRT candidate at RA 00:44:42.45 Dec -81:59:37.0, and we detect no transient sources to an upper limit of 22.5. We note that the error circle closely aligns with a faint (m_G=19.96) red star (Gaia 4630203649665987840).
Date | Filter | Mag | Exp time (s)
---------------------------------------------------------------
2023-11-30 00:53 UT | Open | > 21.9 @ 5-sigma | 2x300 s
2023-11-30 00:53 UT | Open | > 22.5 @ 5-sigma | 6x200 s
- GCN Circular #35251
J. D. Gropp (PSU), S. Dichiara (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi
(INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J.A. Kennea (PSU) and P.A.
Evans (U. Leicester) reports on behalf of the Swift-XRT team:
Swift-XRT has conducted further observations of the field of the
Fermi/GBM-detected burst GRB 231129C. The observations now extend from
T0+34.8 ks to T0+172.6 ks. The source previously reported, "Source 2",
is believed to be the afterglow. The position of this source is RA,
Dec=11.1769, -81.9936 which is equivalent to:
RA (J2000): 00:44:42.45
Dec(J2000): -81:59:37.0
with an uncertainty of 9.5 arcsec (radius, 90% confidence). This
position is 22.4 arcmin from the Fermi/GBM position. We cannot
determine at the present time whether the source is fading.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00021633.
The results of the full analysis of the tiled XRT observations are
available at https://www.swift.ac.uk/xrt_products/TILED_GRB00117.
This circular is an official product of the Swift-XRT team.
- GCN Circular #35256
A. Lysenko, D. Frederiks, A. Ridnaia, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline
on behalf of the Konus-Wind team, report:
The bright long-duration GRB 231129C
(Fermi-GBM detection: Sharma et al., GCN Circ. 35227;
MAXI/GSC detection: Kawakubo et al., GCN Circ. 35223;
CALET detection: Kawakubo et al., GCN Circ. 35228;
AstroSat CZTI detection: Waratkar et al., GCN Circ. 35230;
GECAM-B detection: Zheng et al., GCN Circ. 35231;
Swift-XRT detection: Gropp et al., GCN Circ. 35234;
Glowbug detection: Cheung et al., GCN Circ. 35235;
GRBAlpha detection: Dafcikova et al., GCN Circ. 35236;
Fermi-LAT detection: Arimoto et al., GCN Circ. 35238;
AGILE detection: Panebianco et al., GCN Circ. 35244)
triggered Konus-Wind at T0=69016.319 s UT (19:10:16.319).
The burst light curve shows a bright, multi-peaked pulse
featuring a very strong hard-to-soft spectral evolution.
The pulse starts at ~T0-0.2 and has a total duration of ~9.6 s.
The emission is seen up to ~15 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB231129_T69016/
As observed by Konus-Wind, the burst
had a fluence of 8.60(-0.23,+0.24)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+0.106s,
of 4.16(-0.52,+0.54)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+12.800 s)
is best fit in the 20 keV - 20 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.17(-0.06,+0.06),
the high energy photon index beta = -2.95(-0.12,+0.10),
the peak energy Ep = 202(-6,+6) keV
(chi2 = 151/97 dof).
The spectrum near the maximum count rate
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 20 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.20(-0.14,+0.15)
and Ep = 782(-52,+55) keV (chi2 = 69/51 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -3.3
(chi2 = 69/50 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
- GCN Circular #35288
M. Marisaldi (University of Bergen), A. Mezentsev (University of Bergen), P.Connell, Javier Navarro-Gonzalez (University of Valencia),
N. =C3=98stgaard (University of Bergen), V. Reglero (University of Valencia)
and T. Neubert (DTU Space) report on behalf of the ASIM Team:
At 19:10:18 UT on 29 November 2023, the Atmosphere-Space Interactions Monitor (ASIM)
mission triggered on the long bright GRB 231129C.
The burst was also detected by Fermi-GBM (Sharma et al., GCN Circ. 35221, and Sharma et al., GCN Circ. 227),
MAXI/GSC (Kawakubo et al., GCN Circ. 35223), CALET (Shimizu et al., GCN Circ. 35228),
AstroSat CZTI (Waratkar et al., GCN Circ. 35230), GECAM-B (Zheng et al., GCN Circ. 35231),
Swift-XRT (Gropp et al., GCN Circ. 35234), Glowbug (Cheung et al., GCN Circ. 35235),
GRBAlpha (Dafcikova et al., GCN Circ. 35236), Fermi-LAT (Arimoto et al., GCN Circ. 35238,
AGILE (Panebianco et al., GCN Circ. 35244), and Konus-Wind (Lysenko et al.,
GCN Circ. 35256).
Photon by photon data with <1 microsecond time resolution have been
collected for a time interval of 19 seconds.
The emission is detected in the MXGS High Energy Detector (HED), sensitive =
in the range 0.3 to >30 MeV, =20
and in the MXGS Low Energy Detector (LED), sensitive in the range 0.05 to 0=
.4 MeV.
In January 2022 ASIM was relocated so that the MXGS coded mask imaging syst=
em is pointing towards the Earth=E2=80=99s limb, observing a large fraction=
of unocculted sky, therefore enabling localization of the GRB prompt emiss=
ion.
This GRB was observed within the MXGS Field of View resulting in a very hig=
h significant localization (>100 sigma) at
R.A.,Dec(2000) =3D 00:51:12.56 -81:45:35.5
consistent within a 25 arcmin error (radius, 99% confidence level) with the=
Swift-XRT X-ray afterglow (Gropp et al., GCN Circ. 35251) and the MASTER O=
T detection (Antipov et al., GCN Circ.35240).
ASIM is an ESA mission onboard the International Space Station dedicated to=
the=20
observation of Terrestrial Gamma-ray Flashes (TGFs) and Transient Luminous =
Events (TLEs)=20
operative since June 2018 (Neubert et al., Space Sci Rev (2019) 215:26=20
https://doi.org/10.1007/s11214-019-0592-z ).=20
The payload includes the Modular X- and Gamma-Ray Sensor (MXGS)=20
(=C3=98stgaard et al., Space Sci Rev (2019) 215:23 https://doi.org/10.1007/=
s11214-018-0573-7 ),=20
and the the Modular Multispectral Imaging Array (MMIA)
(Chanrion et al., Space Sci Rev (2019) 215:28
https://doi.org/10.1007/s11214-019-0593-y).
The ASIM Science Data Centre (ASDC) website is https://asdc.space.dtu.dk/
- GCN Circular #35311
A.S. Kozyrev, D.V. Golovin, M.L. Litvak, I.G. Mitrofanov, and A.B. Sanin
on behalf of the MGNS/BepiColombo and HEND/Mars Odyssey teams,
J. Benkhoff on behalf of the BepiColombo team,
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,
S. Barthelmy, J. Cummings, H. Krimm, D. Palmer, and A. Tohuvavohu
on behalf of the Swift-BAT team,
and
W. Boynton, C. Fellows, K. Harshman, H. Enos, R. Starr,
and A.S. Gardner on on behalf of the GRS-Odyssey GRB team,
report:
The very bright, long-duration GRB 231129C
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 35217;
Sharma et al., GCN Circ. 35221, 35227;
BALROG localization: Preis et al., GCN Circ. 35222;
MAXI-GSC detection: Kawakubo et al., GCN Circ. 35223;
CALET-CGBM detection: Shimizu et al., GCN Circ. 35228;
AstroSat-CZTI detection: Waratkar et al., GCN Circ. 35230;
GECAM-B detection: Zheng and Xiong, GCN Circ. 35231;
Glowbug detection: Cheung et al., GCN Circ. 35235;
GRBAlpha detection: Dafcikova et al., GCN Circ. 35236;
Fermi-LAT detection: Arimoto et al., GCN Circ. 35238;
Swift-BAT/GUANO detection: DeLaunay et al., GCN Circ. 35242;
AGILE detection: Panebianco et al., GCN Circ. 35244;
Konus-Wind detection: Lysenko et al., GCN Circ. 35256;
ASIM-MXGS detection: Marisaldi et al., GCN Circ. 35288)
was detected by Fermi (GBM, LAT), ISS (Glowbug, CALET-CGBM),
AstroSat (CZTI), GECAM-B (GRD), GRBAlpha, AGILE (MCAL, AC),
Swift (BAT), Konus-Wind, INTEGRAL (SPI-ACS),
GRBAlpha, Mars-Odyssey (HEND), and BebiColombo (MGNS)
at about 69018 s UT (19:10:18).
The burst was outside the coded field of view of the BAT.
We have triangulated it to a preliminary, 3 sigma error box
whose coordinates are:
---------------------------------------------
RA(2000), deg Dec(2000), deg
---------------------------------------------
Center:
9.975 (00h 39m 54s) -81.812 (-81d 48' 43")
Corners:
4.821 (00h 19m 17s) -80.799 (-80d 47' 56")
16.263 (01h 05m 03s) -82.675 (-82d 40' 29")
16.443 (01h 05m 46s) -82.746 (-82d 44' 45")
4.881 (00h 19m 31s) -80.873 (-80d 52' 23")
---------------------------------------------
The error box area is 322 sq. arcmin, and its maximum
dimension is 2.5 deg (the minimum one is 2.2 arcmin).
The Sun distance was 73 deg.
This localization may be improved.
The IPN localization is consistent with, but reduces the area of,
the Fermi-GBM/LAT and ASIM localizations.
The Swift-XRT reported Source 2 (GCN 35234, 35251) is inside the IPN box, supporting that the source is the afterglow of GRB 231129C.
A triangulation map and HEALPix FITS file are posted at
http://www.ioffe.ru/LEA/GRBs/GRB231129_T69016/IPN/
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