GRB 240226A
GCN Circular 35804
Subject
GRB 240226A: Fermi GBM Final Real-time Localization
Date
2024-02-26T19:43:46Z (a year 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 LONG GRB
At 19:33:07 UT on 26 Feb 2024, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 240226A (trigger 730668792.323378 / 240226815).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 289.1, Dec = -43.1 (J2000 degrees, equivalent to J2000 19h 16m, -43d 06'), with a statistical uncertainty of 9.0 degrees.
The angle from the Fermi LAT boresight is 30.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240226815/quicklook/glg_skymap_all_bn240226815.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/bn240226815/quicklook/glg_healpix_all_bn240226815.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2024/bn240226815/quicklook/glg_lc_medres34_bn240226815.gif
GCN Circular 35817
Subject
Fermi GRB 240226A: Global MASTER-Net observations report
Date
2024-02-27T11:30:55Z (a year ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
legacy email
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-SAAO robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in South Africa (South African Astronomical Observatory) started inspect of the Fermi GRB 240226A ( Fermi GBM team, GCN 35804) errorbox 16246 sec after notice time and 16283 sec after trigger time at 2024-02-27 00:04:30 UT, with upper limit up to 16.8 mag. The observations began at zenith distance = 79 deg. The sun altitude is -45.7 deg.
The galactic latitude b = -23 deg., longitude l = 355 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=2386845
We obtain a following upper limits.
Tmid-T0 | Date Time | Site | Coord (J2000) |Filt.| Expt. | Limit| Comment
_________|_____________________|_____________________|____________________________________|_____|_______|_______|________
16314 | 2024-02-27 00:04:30 | MASTER-SAAO | (19h 06m 29.14s , -46d 29m 24.3s) | C | 60 | 16.3 |
16314 | 2024-02-27 00:04:30 | MASTER-SAAO | (18h 59m 24.88s , -46d 17m 34.7s) | C | 60 | 16.5 |
16393 | 2024-02-27 00:05:50 | MASTER-SAAO | (18h 56m 09.53s , -42d 41m 16.4s) | C | 60 | 16.0 |
16393 | 2024-02-27 00:05:50 | MASTER-SAAO | (18h 49m 32.02s , -42d 29m 23.5s) | C | 60 | 16.4 |
16473 | 2024-02-27 00:07:10 | MASTER-SAAO | (18h 49m 52.02s , -44d 33m 18.5s) | C | 60 | 16.5 |
16473 | 2024-02-27 00:07:10 | MASTER-SAAO | (18h 43m 01.98s , -44d 21m 24.2s) | C | 60 | 16.8 |
16633 | 2024-02-27 00:09:50 | MASTER-SAAO | (19h 04m 23.32s , -44d 22m 12.6s) | C | 60 | 16.7 |
16713 | 2024-02-27 00:11:09 | MASTER-SAAO | (19h 02m 49.54s , -48d 22m 23.9s) | C | 60 | 16.4 |
16713 | 2024-02-27 00:11:09 | MASTER-SAAO | (18h 55m 29.79s , -48d 10m 32.0s) | C | 60 | 16.8 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 35827
Subject
GRB 240226A: GRBAlpha detection
Date
2024-02-28T13:31:18Z (a year ago)
From
Martin Kolář at Masaryk University <mkolar@physics.muni.cz>
Via
Web form
M. Kolar, 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, L. Szakszonova, J.-P. Breuer, F. Hroch (Masaryk U.), T. Urbanec, M. Kasal, A. Povalac (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. Lipovsky (Technical U. of Kosice), G. Galgoczi (Wigner Research Center/Eotvos U.), Y. Uchida, H. Poon, H. Matake (Hiroshima U.), N. Uchida (ISAS/JAXA), T. Bozoki (Eotvos U.), G. Dalya (Eotvos U.), T. Enoto (Kyoto U.), Zs. Frei (Eotvos 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 (Hiroshima U.), N. Kogiso, M. Yoneyama (Osaka Metropolitan U.), M. Moritaki (U. Tokyo), T. Kano (U. Michigan) -- the GRBAlpha collaboration.
The long-duration GRB 240226A (Fermi/GBM detection: GCN 35804) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; https://ui.adsabs.harvard.edu/abs/2023A%26A...677A..40P/abstract).
The sub-threshold detection was confirmed at the peak time 2024-02-26 19:33:09.5 UTC. The T90 duration measured by GRBAlpha is 9.5 s and the overall significance during T90 reaches 4.7 sigma.
The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB240226A_GCN.pdf
All GRBAlpha detections are listed at: https://monoceros.physics.muni.cz/hea/GRBAlpha/
GRBAlpha, launched on 2021 March 22, is a demonstration mission for a future CubeSat constellation (Werner et al. Proc. SPIE 2018). The detector of GRBAlpha consists of a 75 x 75 x 5 mm3 CsI scintillator read out by a SiPM array, covering the energy range from ~50 keV to ~1000 keV. To increase the duty cycle and the downlink rate, the upgrade of the on-board data acquisition software stack is in progress. The ground segment is also supported by the radio amateur community and it takes advantage of the SatNOGS network for increased data downlink volume.