GRB 230614C

S. Lesage (UAH), R. Hamburg (CNRS/ICJLab) and C. Meegan (UAH) report on behalf of
the Fermi Gamma-ray Burst Monitor Team:

"At 10:10:31 UT on 14 June 2023, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 230614C (trigger 708430236/230614424) which 
was also detected by INTEGRAL SPI-ACS (trigger 10284).

The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 229.21, Dec = 10.30 (J2000 degrees, equivalent to
J2000 15h 16m, +10d 18'), with a statistical uncertainty of 1.00 degree
(radius, 1-sigma containment, statistical only; there is additionally a systematic error
which we have characterized as a core-plus-tail model, with 90% of GRBs having a
3.7 deg error and a small tail suffering a larger than 10 deg systematic error
[Connaughton et al. 2015, ApJS, 216, 32]).

The angle from the Fermi LAT boresight is 108 degrees.

The GBM light curve consists of a single emission episode with a duration (T90)
of about 6.1 s (50-300 keV). The time-averaged spectrum
from T0+0.003 to T0+7.488 s is best fit by
a Band function with Epeak = 196 +/- 7 keV,
alpha = -0.50 +/- 0.04, and beta = -2.44 +/- 0.08.

The event fluence (10-1000 keV) in this time interval is
(4.04 +/- 0.06)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.8 s in the 10-1000 keV band is 32.6 +/- 0.5 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/"

P K. Navaneeth (IUCAA), G. Waratkar (IITB), A. Vibhute (IUCAA), V. Bhalerao (IITB), D. Bhattacharya (Ashoka University/IUCAA), A. R. Rao (IUCAA/TIFR), and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:

Analysis of AstroSat CZTI data with the CIFT framework (Sharma et al., 2021, JApA, 42, 73) showed the detection of a long GRB 230614C which was also detected by Fermi GBM (Lesage et al., GCN Circ. 33966
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 ), and INTEGRAL SPI-ACS (Trigger 10284).

The source was clearly detected in the 20-200 keV energy range. The light curve peaks at 2023-06-14 10:10:33.25 UTC. The measured peak count rate associated with the burst is 2133 (+308, -123) counts/s above the background in the combined data of all quadrants, with a total of 5394 (+562, -588) counts. The local mean background count rate was 456 (+9, -12) counts/s. Using cumulative rates, we measure a T90 of 5.1 (+1.3, -1.2) s. In the preliminary analysis, we find 423 Compton events associated with this event.

The source was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. The light curve peaks at 2023-06-14 10:10:33.25 UTC. The measured peak count rate associated with the burst is 2148 (+98, -105) counts/s above the background in the combined data of all quadrants, with a total of 5536 (+476, -514) counts. The local mean background count rate was 1459 (+7, -8) counts/s. We measure a T90 of 5.2 (+4.1, -1.5) s from the cumulative Veto light curve.

CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, URSC, IUCAA, SAC, and PRL. The Indian Space Research Organisation funded, managed, and facilitated the project.

CZTI GRB detections are reported regularly on the payload site at:
http://astrosat.iucaa.in/czti/?q=grb

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, M. Kolar, 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 230614C (Fermi/GBM detection: GCN 33966
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 ; AstroSat detection: GCN 33969
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 ; INTEGRAL/SPI-ACS detection: trigger no. 10284) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023; arXiv:2302.10048
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 ).

The detection was confirmed at the peak time 2023-06-14 10:10:32 UTC. The T90 duration measured by GRBAlpha is 6 s and the overall significance during T90 reaches 43 sigma.

The light curve obtained by GRBAlpha is available here:
https://grbalpha.konkoly.hu/static/share/GRB230614C_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.