GRB 201104A
GCN Circular 28873
Subject
GRB 201104A: AstroSat CZTI detection
Date
2020-11-09T20:42:02Z (6 years ago)
From
Soumya Gupta at IUCAA/ASTROSAT <soumya@iucaa>
S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (IUCAA/TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
The AstroSat CZT Imager recorded a transient event in all four of its CsI anticoincidence (Veto) detectors in the 100-500 keV energy range, coincident with the long GRB 201104A reported by Fermi GBM (GCN #28823), Global MASTER-Net (Lipunov V. et al., GCN #28824), Fermi LAT (Ohno M. et al., GCN #28828), AGILE/MCAL (Ursi A. et al., GCN #28829), Fermi GBM (Bissaldi E. et al., GCN #28830), Tiled Swift (Evans P. et al., GCN #28832), BALROG (Kunzweiler F. et al., GCN #28834) and Swift-XRT (D'Elia V. et al., GCN #28859). There was a weak detection in the main CZT detectors in the 40-200 keV energy range.
The light curve showed multiple peaks of emission with the strongest peak at 2020-11-04 00:00:55.000 UT. The measured peak count rate is 1757 +/- 68 cts/s above the background in the combined Veto data of four quadrants, with a total of 6949 +/- 80 cts. The local mean background count rate was 2774 +/- 5 cts/s. We measure a T90 of 8.18 +/- 0.13 s from the cumulative Veto light curve.
In the main CZT detectors, the light curve showed multiple peaks of emission with the strongest peak at 2020-11-04 00:00:56.000 UT. The measured peak count rate associated with the burst is 330 +/- 33 cts/s above the background in the combined data of four quadrants, with a total of 1170 +/- 23 cts. The local mean background count rate was 792 +/- 2 cts/s. Using cumulative rates, we measure a T90 of 7.36 +/- 0.11 s.
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, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
GCN Circular 28859
Subject
GRB 201104A: Swift-XRT observations
Date
2020-11-06T17:46:49Z (6 years ago)
From
Boris Sbarufatti at PSU <bxs60@psu.edu>
V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), D.N. Burrows (PSU), J. D.
Gropp (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), J.P.
Osborne (U. Leicester), A. Melandri (INAF-OAB) and P.A. Evans (U.
Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 201104A (Ohno et al. GCN Circ. 28828) in a
series of observations tiled on the sky. The total exposure time is 4.7
ks, distributed over 3 tiles; the maximum exposure at a single sky
location was 2.4 ks. The data were collected between T0+67.6 ks and
T0+80.9 ks, and are entirely in Photon Counting (PC) mode.
One uncatalogued X-ray source has been detected, it is not above the
RASS limit or shows definitive signs of fading. Furthermore, it is
coincident with a known optical source and the XRT data are possibly
affected by stray light. Therefore we believe that XRT has not detected
any viable candidate afterglow.
Details of the sources are given below:
Source 3:
RA (J2000.0): 80.9041 = 05:23:36.99
Dec (J2000.0): -71.0096 = -71:00:34.6
Error: 4.1 arcsec (radius, 90% conf. [Enhanced position])
Count-rate: (5.3 [+2.7, -2.0])e-3 ct s^-1
Distance: 664 arcsec from Fermi/LAT position.
Flux: (1.53 [+0.77, -0.59])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)
A catalogued source was also detected inside the LAT error circle, and
two more sources were detected outside of it.
The 3 sigma upper limit at the LAT GRB position is 7.6��10-3 ct s-1.
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_GRB00094.
This circular is an official product of the Swift-XRT team.
GCN Circular 28834
Subject
GRB 201104A: BALROG localization (Fermi Trigger 626140861 / GRB 201104001)
Date
2020-11-04T22:35:07Z (6 years ago)
From
Jochen Greiner at MPE,Garching <jcg@mpe.mpg.de>
F. Kunzweiler, B. Biltzinger, F. Berlato, J. Burgess & J. Greiner (all MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
626140861 at 00:00:56 on 04 Nov. 2020 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) = 67.9+/-10.4 deg
Decl.(2000.0) = -73.2+/-1.6 deg
We estimate an additional systematic error of 2 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB201104001/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB201104001/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB201104001/json
GCN Circular 28832
Subject
GRB 201104A: Tiled Swift observations
Date
2020-11-04T21:22:19Z (6 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
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/LAT GRB 201104A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00094
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/LAT 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 OPS NOTE(06Nov20): Due to the uncertainty of the arrival time with respect
to the downtime window (15 hours) of the GCN Circulars processing system,
the error in the date-time in the header of this Circular can be off anywhere from 0-15 hours.]
GCN Circular 28830
Subject
GRB 201104A: Fermi GBM observation
Date
2020-11-04T20:51:58Z (6 years ago)
From
Christian Malacaria at NASA-MSFC/USRA <cmalacaria@usra.edu>
E. Bissaldi (Politecnico and INFN Bari) and C. Malacaria (NASA-MSFC/USRA)
report on behalf of the Fermi GBM Team:
"At 00:00:56.75 UT on 4 November 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 201104A (trigger 626140861 / 201104001,
which was also detected by the Fermi-LAT (Ohno et al. 2020, GCN 28828)
and AGILE (Ursi et al. 2020, GCN 28829).
The GBM on-ground location is consistent with the LAT position.
The angle from the Fermi LAT boresight at the GBM trigger time is 57 degrees.
The GBM light curve shows a bright emission episode
with a duration (T90) of about 8.4 s (50-300 keV).
The time-averaged spectrum from T0 to T0+9 s is
best fit by a Band function with Epeak = 1140 +/- 130 keV,
alpha = -0.76 +/- 0.04, and beta = -2.24 +/- 0.17.
The event fluence (10-1000 keV) in this time interval is
(1.55 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0 in the 10-1000 keV band
is 12.1 +/- 0.3 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 28829
Subject
GRB 201104A: AGILE/MCAL detection
Date
2020-11-04T20:46:45Z (6 years ago)
From
Alessandro Ursi at INAF/IAPS <alessandro.ursi@gmail.com>
A. Ursi (INAF/IAPS), F. Verrecchia, C. Pittori (SSDC, and INAF/OAR), M.
Tavani (INAF/IAPS, and Univ. Roma Tor Vergata), A. Argan, M. Cardillo, C.
Casentini, Y. Evangelista, G. Piano (INAF/IAPS), F. Lucarelli (SSDC, and
INAF/OAR), A. Bulgarelli, V. Fioretti, F. Fuschino, N. Parmiggiani
(INAF/OAS-Bologna), M. Marisaldi (INAF/OAS-Bologna, and Bergen University),
M. Pilia, A. Trois (INAF/OA-Cagliari), I. Donnarumma (ASI), F. Longo (Univ.
Trieste and INFN Trieste), A. Giuliani (INAF/IASF-Mi), report on behalf of
the AGILE Team:
The AGILE Mini-CALorimeter (MCAL) detected GRB 201104A at T0 = 2020-11-04
00:00:56.77 +/- 0.01 s (UTC), reported by Fermi/GBM (GCN #28823) and
INTEGRAL/SPI-ACS (trigger ID 8789,0).
The event lasted about 8 s and released a total number of ~7200 counts in
the detector (in the 0.4-100 MeV energy range), above an average background
rate of 640 Hz.
The light curve shows sveral episodes and can be found at
http://www.agilescienceapp.it/notices/GRB_070287_531532856.770000.png .
The time-integrated spectrum of the burst can be fitted in the energy range
0.4-20 MeV with a single power-law with ph.ind. = -2.26 -0.15/+0.18,
resulting in a reduced chi-squared of 1.06 (75 d.o.f.) and a fluence of
3.57e-06 ergs/cm^2 (90% confidence level), in the same energy range.
The burst is clearly visible in the AGILE scientific ratemeters of the MCAL
detector. The event released a total number of 25100 counts, above a
background rate of 1255 Hz. The AGILE ratemeter light curves can be found
at http://www.agilescienceapp.it/notices/GRB_201104A_AGILE_RM.png .
The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the
energy range 0.4-100 MeV. 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 OPS NOTE(06Nov20): Due to the uncertainty of the arrival time with respect
to the downtime window (15 hours) of the GCN Circulars processing system,
the error in the date-time in the header of this Circular can be off anywhere from 0-15 hours.]
GCN Circular 28828
Subject
GRB 201104A: Fermi-LAT detection
Date
2020-11-04T20:30:07Z (6 years ago)
From
Masanori Ohno at Hiroshima University <ohno@astro.hiroshima-u.ac.jp>
M. Ohno (Hiroshima U./Eotvos U.), N. Omodei (Stanford University), F. Longo
(University & INFN Trieste) and M. Axelsson (KTH & Stockholm Univ.)
report on behalf of the Fermi-LAT Collaboration:
On November 4, 2020, Fermi-LAT detected high-energy emission from
GRB 201104A, which was also detected by Fermi-GBM (trigger
626140861/201104001) (Fermi-GBM team; GCN Circ. 28823).
The best LAT on-ground location is found to be
RA, Dec = 81.4, -71.1 (degrees, J2000)
with an error radius of 0.24 deg (90% containment, statistical error only).
This was 6.7 deg from the LAT boresight at the time of the GBM trigger:
T0 = 00:00:56 UT.
The source quickly went out from the LAT FoV but the data from the
Fermi-LAT show a significant increase
in the event rate after the GBM trigger that is spatially and temporally
correlated with the
GBM emission with high significance.
The photon flux above 100 MeV in the time interval 0-100 s after the
GBM trigger is (2.6+/-0.4)e-4 ph/cm2/s.
The estimated photon index above 100 MeV is -2.5 +/- 0.2.
The highest-energy photon is a 3.7 GeV event which is observed 16 seconds
after the GBM trigger.
A Swift ToO has been requested for this burst
The Fermi-LAT point of contact for this burst is
Masanori Ohno (ohno@astro.hiroshima-u.ac.jp).
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 OPS NOTE(06Nov20): Due to the uncertainty of the arrival time with respect
to the downtime window (15 hours) of the GCN Circulars processing system,
the error in the date-time in the header of this Circular can be off anywhere from 0-15 hours.]
GCN Circular 28824
Subject
Fermi GRB 201104A: Global MASTER-Net observations report
Date
2020-11-04T00:15:27Z (6 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin,
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov, D. Cheryasov
(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, O.Ershova
(Irkutsk State University, API),
A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko
(Blagoveschensk Educational State University)
MASTER-OAFA robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Argentina (OAFA observatory of San Juan National University) started inspect of the Fermi GRB 201104A ( Fermi GBM team, GCN 28823) errorbox 80 sec after trigger time at 2020-11-04 00:02:17 UT, with upper limit up to 17.8 mag. Observations started at twilight. The observations began at zenith distance = 59 deg. The sun altitude is -13.0 deg.
The galactic latitude b = -38 deg., longitude l = 287 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1475503
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
90 | 2020-11-04 00:02:17 | MASTER-OAFA | (03h 58m 14.15s , -74d 30m 15.1s) | C | 20 | 17.4 |
130 | 2020-11-04 00:02:56 | MASTER-OAFA | (03h 58m 07.55s , -74d 31m 15.8s) | C | 20 | 17.3 |
174 | 2020-11-04 00:03:35 | MASTER-OAFA | (03h 58m 15.37s , -74d 30m 56.0s) | C | 30 | 17.4 |
228 | 2020-11-04 00:04:25 | MASTER-OAFA | (03h 58m 11.98s , -74d 29m 19.8s) | C | 40 | 17.6 |
293 | 2020-11-04 00:05:24 | MASTER-OAFA | (03h 58m 12.40s , -74d 30m 55.2s) | C | 50 | 17.8 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 28823
Subject
GRB 201104A: Fermi GBM Final Real-time Localization
Date
2020-11-04T00:11:18Z (6 years ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
The Fermi GBM team reports the detection of a likely LONG GRB
At 00:00:56 UT on 4 Nov 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 201104A (trigger 626140861.749996 / 201104001).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 60.4, Dec = -72.7 (J2000 degrees, equivalent to J2000 04h 01m, -72d 42'), with a statistical uncertainty of 1.0 degrees.
The angle from the Fermi LAT boresight is 65.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn201104001/quicklook/glg_skymap_all_bn201104001.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn201104001/quicklook/glg_healpix_all_bn201104001.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn201104001/quicklook/glg_lc_medres34_bn201104001.gif