GRB 241207B
GCN Circular 38461
Subject
GRB 241207B: Fermi GBM Final Real-time Localization
Date
2024-12-07T21:01:43Z (6 months ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
Via
email
The Fermi GBM team reports the detection of a likely SHORT GRB
At 20:51:01 UT on 7 Dec 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 241207B (trigger 755297466.745718 / 241207869).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 234.8, Dec = -14.3 (J2000 degrees, equivalent to J2000 15h 39m, -14d 18'), with a statistical uncertainty of 8.0 degrees.
The angle from the Fermi LAT boresight is 64.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn241207869/quicklook/glg_skymap_all_bn241207869.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn241207869/quicklook/glg_healpix_all_bn241207869.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn241207869/quicklook/glg_lc_medres34_bn241207869.gif
GCN Circular 38472
Subject
GRB 241207B: Swift/BAT-GUANO localization skymap of a short burst
Date
2024-12-09T03:53:49Z (6 months ago)
From
Jimmy DeLaunay at Penn State <delauj2@gmail.com>
Via
Web form
James DeLaunay (PSU), Samuele Ronchini (PSU), Aaron Tohuvavohu (Caltech), Gayathri Raman (PSU), Jamie A. Kennea (PSU), Tyler Parsotan (NASA GSFC) report:
Swift/BAT did not localize GRB 241207B onboard (T0: 2024-12-07T20:51:01.75 UTC, Fermi trig 755297466)
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 2022, ApJ, 941, 169), performed on the temporal window [T0-20 s, T0+20 s], detects the burst with a sqrt(TS) of 10.3 in a 0.256 s analysis time bin, starting at T0 - 0.128 s.
Using the NITRATES analysis, parameter estimation was performed to obtain the localization of this burst in the form of a HEALPIX Multi-Order Coverage (MOC) skymap. This localization accounts for both statistical and systematic errors. More details in the creation and calibration of these maps will soon be published (DeLaunay et al. 2024. in prep)
The 90% credible area is 6,453 deg2 and the 50% credible area is 336 deg2.
The integrated probability inside the coded field of view is <1%.
The NITRATES skymap is consistent with the Fermi localization reported in the final position notice (GCN 38461). The combined Fermi/GBM+NITRATES 90% credible area is 358 deg2 and the 50% credible area is 108 deg2.
A plot of the probability skymap can be viewed here:
[skymap_plot](https://guano.swift.psu.edu/trigger_report?id=755297496/#:~:text=Probability%20Skymap)
The probability skymap file can be downloaded from the link here
[skymap_fits_file](https://guano.swift.psu.edu/files/755297496/0_n_PROBMAP)
Instructions on how to read and manipulate this map can be found here:
https://guano.swift.psu.edu/documentation
More details about this burst can be found on the trigger report page here:
https://guano.swift.psu.edu/trigger_report?id=755297496
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 38473
Subject
Fermi GRB 241207B: Global MASTER-Net observations report
Date
2024-12-09T04:30:45Z (6 months ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
legacy email
V.Lipunov, E.Gorbovskoy, N.Tiurina, P.Balanutsa, , D.Vlasenko, I.Panchenko,
A.Kuznetsov, G.Antipov, A.Sankovich, A.Sosnovskij, Yu.Tselik, M.Gulyaev, 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. 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-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) started inspect of the Fermi GRB 241207B ( Fermi GBM team, GCN 38461) errorbox 1 days 24239 sec after notice time and 1 days 24273 sec after trigger time at 2024-12-09 03:35:34 UT, with upper limit up to 17.2 mag. Observations started at twilight. The observations began at zenith distance = 78 deg. The sun altitude is -15.5 deg.
The galactic latitude b = 31 deg., longitude l = 353 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=2699915
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
110763 | 2024-12-09 03:35:34 | MASTER-Tavrida | (15h 02m 40.58s , -11d 54m 25.0s) | C | 180 | 16.6 |
110959 | 2024-12-09 03:38:50 | MASTER-Tavrida | (15h 10m 53.06s , -11d 52m 58.7s) | C | 180 | 17.2 |
111160 | 2024-12-09 03:42:12 | MASTER-Tavrida | (15h 02m 36.75s , -11d 53m 42.6s) | C | 180 | 15.2 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 38510
Subject
GRB 241207B: Fermi GBM Observation
Date
2024-12-10T01:28:08Z (6 months ago)
From
Lorenzo Scotton at UAH <lscottongcn@outlook.com>
Via
Web form
L. Scotton (UAH) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:
"At 20:51:01.75 UT on 07 December 2024, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 241207B (trigger 755297466/241207869)
which was also detected by Swift/BAT-NITRATES (DeLaunay et al. 2024, GCN 38472).
The Fermi GBM on-ground location is consistent with the Swift/BAT-NITRATES position.
The angle from the Fermi LAT boresight is 64 degrees.
The GBM light curve consists of a single emission episode with a duration (T90)
of about 0.3 s (50-300 keV). The time-averaged spectrum
from T0-0.2 to T0+0.4 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.7 +/- 0.2 and the cutoff energy,
parameterized as Epeak, is 344 +/- 110 keV.
The event fluence (10-1000 keV) in this time interval is
(3.8 +/- 0.6)E-07 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.0 s in the 10-1000 keV band is 7 +/- 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/"