TITLE: GCN CIRCULAR
NUMBER: 35615
SUBJECT: GRB 240124A?: BALROG localization (Fermi Trigger 727752941 / GRB 240124066)
DATE: 24/01/24 02:13:00 GMT
FROM: Jochen Greiner at MPE <jcgrog(a)mpe.mpg.de>
B. Biltzinger, T. Preis, J. Burgess & J. Greiner (all MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
727752941 at 01:35:36 on 24 Jan. 2024 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) = 316.73+/-0.58 deg
Decl.(2000.0) = -22.75+/-0.39 deg
We estimate an additional systematic error of 1 deg.
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB240124066/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB240124066/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB240124066/json
View this GCN Circular online at https://gcn.nasa.gov/circulars/35615.
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TITLE: GCN CIRCULAR
NUMBER: 35614
SUBJECT: Fermi GRB 240123B: Global MASTER-Net observations report
DATE: 24/01/23 23:15:32 GMT
FROM: Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov(a)xray.sai.msu.ru>
V. Lipunov, V.Kornilov, E. Gorbovskoy, K. Zhirkov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.Senik, D. Vlasenko,
G.Antipov, D.Zimnukhov, E.Minkina, A.Chasovnikov, V.Topolev, D.Kuvshinov, D. Cheryasov, Ya.Kechin, Yu.Tselik, A. Sosnovskij
(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. Gress, N.M. Budnev, O.Ershova
(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),
V. Yurkov, A. Gabovich
(Blagoveschensk Educational State University)
MASTER-Tunka robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Applied Physics Institute, Irkutsk State University) started inspect of the Fermi GRB 240123B ( Fermi GBM team, GCN 35608) errorbox 17492 sec after notice time and 17523 sec after trigger time at 2024-01-23 22:40:06 UT, with upper limit up to 17.1 mag. The observations began at zenith distance = 79 deg. The sun altitude is -21.0 deg.
The galactic latitude b = -17 deg., longitude l = 64 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=2363736
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
17534 | 2024-01-23 22:40:06 | MASTER-Tunka | (20h 45m 43.98s , +25d 49m 07.9s) | C | 20 | 16.9 |
17626 | 2024-01-23 22:41:41 | MASTER-Tunka | (20h 25m 46.01s , +22d 02m 50.8s) | C | 15 | 16.9 |
17669 | 2024-01-23 22:42:23 | MASTER-Tunka | (20h 26m 42.78s , +23d 55m 03.1s) | C | 15 | 17.1 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35614.
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TITLE: GCN CIRCULAR
NUMBER: 35613
SUBJECT: GRB 240122A: Swift/UVOT Upper Limits
DATE: 24/01/23 22:57:57 GMT
FROM: Mike Siegel at PSU/Swift MOC <mhs18(a)psu.edu>
M. H. Siegel (PSU) and and V. D’Elia (SSDC & INAF-OAR) report on behalf of the
Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 240122A
from 29.5 ks to 35.6 ks after the MAXI trigger (Negoro et al., GCN Circ. 35593).
No optical afterglow consistent with either the optical (Kumar et al., GCN
Circ. 35596) or X-ray (Ambrosi et al., GCN Circ. 3600) position is detected in the initial
UVOT exposures. The lack of detection in the u-band would be consistent with the
redshift of 3.162 given by Saccardi et al. (GCN Circ. 35599).
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures of
the candidate afterglow field are:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 35166 35655 481 >20.4
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.064 in the direction of the burst
(Schlegel et al. 1998).
View this GCN Circular online at https://gcn.nasa.gov/circulars/35613.
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TITLE: GCN CIRCULAR
NUMBER: 35612
SUBJECT: GRB 240123A: Swift-XRT refined Analysis
DATE: 24/01/23 22:11:25 GMT
FROM: Phil Evans at U of Leicester <pae9(a)star.le.ac.uk>
M. Capalbi (INAF-IASFPA), M. Perri (SSDC & INAF-OAR), J. D. Gropp
(PSU), S. Dichiara (PSU), J.A. Kennea (PSU), J.P. Osborne (U.
Leicester), K.L. Page (U. Leicester), A.P. Beardmore (U. Leicester), V.
D'Elia (SSDC & INAF-OAR) and P.A. Evans report on behalf of the
Swift-XRT team:
We have analysed 6.5 ks of XRT data for GRB 240123A, from 131 s to 23.7
ks after the BAT trigger. The data comprise 164 s in Windowed Timing
(WT) mode (the first 8 s were taken while Swift was slewing) with the
remainder in Photon Counting (PC) mode. The refined XRT position is RA,
Dec = 199.3473, +60.6184 which is equivalent to:
RA (J2000): 13 17 23.34
Dec(J2000): +60 37 06.1
with an uncertainty of 3.5 arcsec (radius, 90% confidence).
The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=7.2 (+0.8, -2.8). At T+145 s the decay
flattens to an alpha of 0.3 (+1.0, -1.8). The light curve breaks again
at T+183 s to a decay with alpha=2.91 (+0.20, -0.19), before a final
break at T+635 s s after which the decay index is 0.58 (+/-0.08).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.35 (+0.09, -0.07). The
best-fitting absorption column is consistent with the Galactic value
of 1.4 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has
a photon index of 2.01 (+0.17, -0.13) and a best-fitting absorption
column of 2.3 (+3.3, -0.9) x 10^20 cm^-2. The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum is 3.2 x 10^-11 (3.4 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 2.3 (+3.3, -0.9) x 10^20 cm^-2
Galactic foreground: 1.4 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index: 2.01 (+0.17, -0.13)
If the light curve continues to decay with a power-law decay index of
0.58, the count rate at T+24 hours will be 0.028 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.0 x
10^-13 (9.6 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/01210276.
This circular is an official product of the Swift-XRT team.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35612.
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TITLE: GCN CIRCULAR
NUMBER: 35611
SUBJECT: GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
DATE: 24/01/23 19:50:44 GMT
FROM: Youdong HU at IAA-CSIC <huyoudong072(a)hotmail.com>
Y.-D. Hu, F. Aceituno, E. Fernandez-Garcia, A. J. Castro-Tirado, M.D. Caballero-Garcia, R. Sanchez-Ramirez, I. Perez-Garcia, S.-Y. Wu, S. Guziy (IAA-CSIC), C. Perez del Pulgar, A. Castellon, I. Carrasco, A. Reina (Univ. de Malaga), R. Fernandez-Munoz (IHSM/UMA-CSIC) and M. Jelinek (ASU-CAS), on behalf of a larger collaboration, report:
Following the detection of GRB 240122A by MAXI/GSC (Negoro et al., GCNC 35593), we triggered the 0.6m BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain), and pointing to the burst position on Jan. 22 at 19:45 UT (i.e. ~9.3 hrs after trigger). In the co-added image (14 x 60 s, clear filter, affected by the bright moonlight), the optical afterglow reported by GOTO (Kumar et al. GCNC 35596), GTC (Thoene et al. GCNC 35598) and VLT (Saccardi et al. GCNC 35599) is not detected down to 17.6 mag, which is consistent with the limit reported by LT (GCNC 35597).
Later on, we triggered the 1.5m telescope at Observatorio de Sierra Nevada (OSN) near Granada, Spain, starting on Jan. 22 at 23:46 UT (i.e. 13.3 hrs after trigger) in BVRI bands. The afterglow is clearly detected with I~20.1+-0.1 mag in the co-added image (7 x 90 s), and consistent with the enhanced XRT/Swift position (Ambrosi et al. GCNC 35600). Further imaging is ongoing.
We thank the staff at both IHSM/UMA-CSIC La Mayora and OSN for their excellent support.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35611.
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TITLE: GCN CIRCULAR
NUMBER: 35610
SUBJECT: Fermi GBM Sub-Threshold Detection of GRB 240123A
DATE: 24/01/23 19:36:21 GMT
FROM: Lorenzo Scotton at UAH <lscottongcn(a)outlook.com>
L. Scotton (UAH) reports on behalf of the Fermi-GBM Team:
Swift-BAT detected GRB 240123A at 11:05:46 UT (D'Ai et al. 2024, GCN 35602). There was no
Fermi-GBM onboard trigger around the event.
An automated, blind search for short gamma-ray bursts below the onboard
triggering threshold in Fermi-GBM identified no counterparts.
The GBM targeted search [1], the most sensitive, coherent search for
GRB-like signals identified a transient most significantly on the 8.192 s
timescale, with a false alarm rate of 3.9e-05 Hz and a location consistent with
the Swift-BAT event, using the standard search protocol with a S/N of 13.
The GBM targeted search event was found with the highest
significance with a "normal" spectrum (Band function with Epeak = 230 keV, alpha = -1.0, beta = -2.3) for a GRB.
[1] Goldstein et al. 2019 arXiv:1903.12597
View this GCN Circular online at https://gcn.nasa.gov/circulars/35610.
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TITLE: GCN CIRCULAR
NUMBER: 35609
SUBJECT: GRB 240123A: Mondy continued optical observations + correction of the GRB name in GCN 35605
DATE: 24/01/23 18:06:11 GMT
FROM: Alexei Pozanenko at IKI, Moscow <apozanen(a)iki.rssi.ru>
N. Pankov (HSE, IKI), A. Pozanenko (IKI), E. Klunko (ISTP), S. Belkin (IKI) report on behalf of GRB IKI FuN:
We continued to observe the afterglow of GRB 240123A (D'Ai et al., GCN 35602) with AZT-33IK telescope of Mondy observatory in R-filter originally started on 2024-01-23 (UT) 14:00:48 (Pankov et al., GCN 35605). We confirm the afterglow decay, which detected previously (D'Ai et al., GCN 35602; Pankov et al., GCN 35605).
Preliminary photometry of the afterglow is following
Date UT start t-T0 Exp. Filter OT Err. UL(3sigma)
(mid, days) (s)
2024-01-23 16:03:39 0.227009 29x120 R 19.87 0.10 21.9
The photometry is based on nearby USNO-B1.0 R2 stars.
We are also reporting the incorrect name of the GRB in GCN Circular No. 35605. The correct name of the GRB in GCN Circular #3560 should be GRB 240123A.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35609.
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TITLE: GCN CIRCULAR
NUMBER: 35607
SUBJECT: GRB 240118: Swift/UVOT Upper Limits
DATE: 24/01/23 17:35:39 GMT
FROM: Mike Siegel at PSU/Swift MOC <mhs18(a)psu.edu>
M. H. Siegel (PSU) reports on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 240118
96191 s after the LAT trigger (Bissaldi et al., GCN Circ. 35560). No optical afterglow consistent with the
LAT position or the XRT position (Beardmore et al., GCN Circ. 35587) is detected in the initial UVOT exposures.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 96191 103639 3161 >20.8
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.056 in the direction of the burst
(Schlegel et al. 1998).
View this GCN Circular online at https://gcn.nasa.gov/circulars/35607.
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TITLE: GCN CIRCULAR
NUMBER: 35606
SUBJECT: GRB 240122B: Glowbug gamma-ray detection
DATE: 24/01/23 17:26:28 GMT
FROM: C.C. Cheung at Naval Research Lab <Teddy.Cheung(a)nrl.navy.mil>
C.C. Cheung, M. Kerr, J.E. Grove, R. Woolf (NRL), A. Goldstein (USRA), C.A. Wilson-Hodge, D. Kocevski (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 240122B, which was also detected by CALET/CGBM (Trigger 1389985993).
Using an adaptive window with a resolution of 32-ms, the burst onset is determined to be 2024-01-22 19:16:24.160 with a duration of 21.5 s and a total significance of about 28.9 sigma. The light curve comprises a single peak.
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/dE~E^x of x=2.2 and a cutoff energy ("Epeak") of 211 keV. The modeled 10-10000 keV fluence is 2.0e-06 erg/cm^2.
The best-fit localization is RA, Decl. (J2000, deg) = 22.8, 59.3 with a radius of 12.4 deg (95% confidence), with a highly uncertain systematic uncertainty.
The analysis results presented here are preliminary and use a response function that lacks a detailed characterization of the surrounding passive structure of the ISS.
Glowbug is a NASA-funded technology demonstrator for sensitive, low-cost gamma-ray transient telescopes developed, built, and operated by the U.S. Naval 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’s 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 unlimited.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35606.
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