Gamma-ray Burst 221215A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Thu 15 Dec 22 04:14:57 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      47
TRIGGER_NUM:     692770472
GRB_RA:          135.050d {+09h 00m 12s} (J2000),
                 135.436d {+09h 01m 45s} (current),
                 134.207d {+08h 56m 50s} (1950)
GRB_DEC:         +45.550d {+45d 32' 60"} (J2000),
                 +45.459d {+45d 27' 33"} (current),
                 +45.746d {+45d 44' 44"} (1950)
GRB_ERROR:       33.77 [deg radius, statistical plus systematic]
GRB_INTEN:       77 [cnts/sec]
DATA_SIGNIF:     5.20 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        19928 TJD;   349 DOY;   22/12/15
GRB_TIME:        15267.97 SOD {04:14:27.97} UT
GRB_PHI:         145.00 [deg]
GRB_THETA:        60.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      0.71
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      96%  GRB
2nd_MOST_LIKELY:   2%  Generic Transient
DETECTORS:       0,0,0, 0,0,0, 0,0,0, 1,0,1, 0,0,
SUN_POSTN:       262.55d {+17h 30m 12s}  -23.26d {-23d 15' 31"}
SUN_DIST:        132.09 [deg]   Sun_angle= 8.5 [hr] (West of Sun)
MOON_POSTN:      163.07d {+10h 52m 17s}  +12.16d {+12d 09' 52"}
MOON_DIST:        40.74 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      174.80, 41.11 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      123.89, 27.27 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_lc_medres34_bn221215177.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 32.15,6.93 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Thu 15 Dec 22 04:15:16 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      58
TRIGGER_NUM:     692770472
GRB_RA:          115.680d {+07h 42m 43s} (J2000),
                 116.087d {+07h 44m 21s} (current),
                 114.791d {+07h 39m 10s} (1950)
GRB_DEC:         +44.520d {+44d 31' 12"} (J2000),
                 +44.464d {+44d 27' 51"} (current),
                 +44.639d {+44d 38' 19"} (1950)
GRB_ERROR:       13.55 [deg radius, statistical only]
DATA_SIGNIF:     5.80 [sigma]
DATA_INTERVAL:   1.024 [sec]
GRB_DATE:        19928 TJD;   349 DOY;   22/12/15
GRB_TIME:        15267.97 SOD {04:14:27.97} UT
GRB_PHI:         154.00 [deg]
GRB_THETA:        71.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4173 (Gnd S/W Version number)
SUN_POSTN:       262.55d {+17h 30m 12s}  -23.26d {-23d 15' 31"}
SUN_DIST:        145.40 [deg]   Sun_angle= 9.8 [hr] (West of Sun)
MOON_POSTN:      163.07d {+10h 52m 17s}  +12.16d {+12d 09' 48"}
MOON_DIST:        51.43 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      174.49, 27.42 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      109.58, 22.81 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_lc_medres34_bn221215177.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_692770472.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
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:     Thu 15 Dec 22 04:23:54 UT
NOTICE_TYPE:     Fermi-GBM Final Position
RECORD_NUM:      0
TRIGGER_NUM:     692770472
GRB_RA:          156.060d {+10h 24m 14s} (J2000),
                 156.395d {+10h 25m 35s} (current),
                 155.327d {+10h 21m 19s} (1950)
GRB_DEC:         +38.640d {+38d 38' 24"} (J2000),
                 +38.523d {+38d 31' 23"} (current),
                 +38.894d {+38d 53' 37"} (1950)
GRB_ERROR:       13.60 [deg radius, statistical only]
GRB_DATE:        19928 TJD;   349 DOY;   22/12/15
GRB_TIME:        15267.97 SOD {04:14:27.97} UT
GRB_PHI:         135.00 [deg]
GRB_THETA:        45.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   41731 (Gnd S/W Version number)
SUN_POSTN:       262.56d {+17h 30m 14s}  -23.26d {-23d 15' 32"}
SUN_DIST:        116.49 [deg]   Sun_angle= 7.1 [hr] (West of Sun)
MOON_POSTN:      163.14d {+10h 52m 34s}  +12.13d {+12d 07' 59"}
MOON_DIST:        27.06 [deg]
MOON_ILLUM:      62 [%]
GAL_COORDS:      182.89, 57.28 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      142.94, 26.54 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_lc_medres34_bn221215177.gif
LOC_URL:         http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_locplot_all_bn221215177.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:        This is likely a Long GRB.

GCN Circular #33054
The Fermi GBM team reports the detection of a likely LONG GRB
At 04:14:27 UT on 15 Dec 2022, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 221215A (trigger 692770472.974848 / 221215177).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 156.1, Dec = 38.6 (J2000 degrees, equivalent to J2000 10h 24m, 38d 36'), with a statistical uncertainty of 13.6 degrees.
The angle from the Fermi LAT boresight is 45.0 degrees.
The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_skymap_all_bn221215177.png
The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_healpix_all_bn221215177.fit
The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2022/bn221215177/quicklook/glg_lc_medres34_bn221215177.gif
GCN Circular #33062
James DeLaunay (UAlabama), Aaron Tohuvavohu (U Toronto), Gayathri Raman (PSU), Jamie A. Kennea (PSU) report:
Swift/BAT did not localize GRB 221215A onboard (T0: 2022-12-15T04:14:27 UTC, Fermi/GBM GCN 33054).
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 200 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, arXiv:2111.01769), detects the burst in a 4.096 s analysis time bin with a sqrt(TS) of 11.8.
An arcminute localization is found with DeltaLLHOut of 19.7 and a DeltaLLHPeak of 7.3. Cross-correlation imaging also finds this source with SNR 5.5.
See Section 9.1 and Figures 10 and 17 in the NITRATES paper for brief descriptions and interpretations of sqrt(TS), DeltaLLHPeak, and DeltaLLHOut.
The BAT position is RA, Dec = 155.056, +46.873 deg which is
```
   RA(J2000)  = 10h 20m 13.34s
   Dec(J2000) = +46d 52′ 21.7″
```
with an estimated uncertainty of 3 arcmin radius.
XRT and UVOT follow-up has been requested. Results of follow-up observations will be reported in future circulars.
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 #33063
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Swift/BAT-GUANO GRB 221215A. Automated analysis of the XRT data will be presented online at https://www.swift.ac.uk/ToO_GRBs/00021533
Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the Swift/BAT-GUANO event. 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 #33072
K.L. Page (U. Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M. Capalbi (INAF-IASFPA), J. D. Gropp (PSU), S. Dichiara (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the Swift/BAT-GUANO-detected burst GRB 221215A, collecting 2.8 ks of Photon Counting (PC) mode data between T0+97.3 ks and T0+113.8 ks.
No X-ray sources have been detected consistent with being within 296 arcsec of the Swift/BAT-GUANO position. The 3-sigma upper limit in the field is 0.005 ct s^-1, corresponding to a 0.3-10 keV observed flux of 1.9e-13 erg cm^-2 s^-1 (assuming a typical GRB spectrum).
An uncatalogued was detected, however this was too far from the GRB position to be the afterglow.
The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at https://www.swift.ac.uk/ToO_GRBs/00021533.
This circular is an official product of the Swift-XRT team.
GCN Circular #33083
O.J. Roberts (USRA/NASA), J. Wood (NASA) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 04:14:27.97 UT on 15 December 2022, the Fermi Gamma-Ray Burst Monitor (GBM) triggered and located GRB 221215A (trigger 692770472 / 221215177) which was also detected by the Swift/BAT GUANO (DeLaunay et al. 2022, GCN 33062) The Fermi GBM Final Real-time Localization (GCN 33054) is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 53 degrees.
The GBM light curve shows a FRED-like pulse with a duration (T90) of about 14 s (50-300 keV). The time-averaged spectrum from T0-2 s to T0+12 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is 1.6 +/- 1.3 and the cutoff energy, parameterized as Epeak, is 165 +/- 26 keV
The event fluence (10-1000 keV) in this time interval is (6.8 +/- 1.2)E-07 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.7 s in the 10-1000 keV band is 29.8 +/- 9.4 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/"

Back to JG's homepage

Jochen Greiner, last update: 19-Dec-2022 [Disclaimer]