TITLE: GCN CIRCULAR
NUMBER: 35386
SUBJECT: GRB 231215A: Swift-BAT refined analysis
DATE: 23/12/17 04:59:08 GMT
FROM: Takanori Sakamoto at AGU <tsakamoto(a)phys.aoyama.ac.jp>
S. D. Barthelmy (GSFC), P. D'Avanzo (INAF-OAB), H. A. Krimm (NSF),
S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa), C. B. Markwardt (GSFC),
M. Moss (GSFC), D. M. Palmer (LANL), T. Parsotan (GSFC/UMBC),
T. Sakamoto (AGU), M. Stamatikos (OSU)
(i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 231215A (trigger #1202522)
(D'Avanzo, et al., GCN Circ. 35343). The BAT ground-calculated position is
RA, Dec = 9.730, 57.634 deg which is
RA(J2000) = 00h 38m 55.1s
Dec(J2000) = +57d 38' 00.8"
with an uncertainty of 1.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 6%.
The mask-weighted light curve shows a structure of several overlapping pulses.
The emission starts from T-10 s, peaks at T0 and ends at T+20 s.
T90 (15-350 keV) is 20.75 +- 3.69 sec (estimated error including systematics).
The time-averaged spectrum from T-7.04 to T+19.79 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.01 +- 0.09. The fluence in the 15-150 keV band is 1.0 +- 0.1 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+0.18 sec in the 15-150 keV band
is 9.6 +- 1.4 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1202522/BA/
View this GCN Circular online at https://gcn.nasa.gov/circulars/35386.
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TITLE: GCN CIRCULAR
NUMBER: 35385
SUBJECT: GRB 231214A: Swift-BAT refined analysis
DATE: 23/12/17 04:55:15 GMT
FROM: Takanori Sakamoto at AGU <tsakamoto(a)phys.aoyama.ac.jp>
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), R. Brivio (INAF-OAB),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (U Tampa),
C. B. Markwardt (GSFC), M. Moss (GSFC), D. M. Palmer (LANL),
T. Parsotan (GSFC/UMBC), T. Sakamoto (AGU)
(i.e. the Swift-BAT team):
Using the data set from T-35 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 231214A (trigger #1202386)
(Brivio, et al., GCN Circ. 35335). The BAT ground-calculated position is
RA, Dec = 305.666, -72.432 deg which is
RA(J2000) = 20h 22m 39.7s
Dec(J2000) = -72d 25' 54.3"
with an uncertainty of 1.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 39%.
The mask-weighted light curve shows two bright overlapping peaks. The first
peak starts from T-5 s, peaks at T+1 s and ends at T+10 s. The second peak
starts from T+10 s, peaks at T+12 s and ends at T+25 s.
T90 (15-350 keV) is 27.8 +- 7.3 sec (estimated error including systematics).
The time-averaged spectrum from T-5.37 to T+49.42 sec is best fit by a power law
with an exponential cutoff. This fit gives a photon index 0.87 +- 0.23,
and Epeak of 167 +- 94 keV (chi squared 60.53 for 56 d.o.f.). For this
model the total fluence in the 15-150 keV band is 9.6 +- 0.3 x 10^-6 erg/cm2
and the 1-sec peak flux measured from T+12.57 sec in the 15-150 keV band is
11.3 +- 0.6 ph/cm2/sec. A fit to a simple power law gives a photon index
of 1.25 +- 0.05 (chi squared 69.34 for 57 d.o.f.). All the quoted errors
are at the 90% confidence level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/1202386/BA/
View this GCN Circular online at https://gcn.nasa.gov/circulars/35385.
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TITLE: GCN CIRCULAR
NUMBER: 35384
SUBJECT: GRB 231216A: R-band observations from T120 at Observatoire de Haute-Provence
DATE: 23/12/16 23:40:34 GMT
FROM: Christophe Adami at LAM <christophe.adami(a)lam.fr>
S. Basa (OHP/Pythéas/LAM), C. Adami (Pythéas/LAM), Y. Degot-Longhi (OHP/Pythéas), A. Saccardi (GEPI, Obs. de Paris), D. Adrien, E. Le Floc'h, F. Schüssler,
D. Turpin (CEA Paris-Saclay), report on behalf of a larger collaboration:
We observed the field of GRB231216A (GCN 35378; Sbarrato et al.) using the T120cm camera at Observatoire de Haute-Provence (France).
We began our observations on 2023 16 December 21:37:24 UT (~3h after the trigger time) with a series of R-band (10x300s) images.
Last image was taken at 22:37:51 UT.
Consistently with Lipunov et al. (GCN 35379), Hu et al. (GCN 35381), Malesani et al. (GCN 35382), and Sharma et al. (GCN 35383), we did not
detect any credible optical counterpart to GRB231216A within the GCN 35378 Swift XRT error box.
Using the r-band PanStarr public image, the faintest detected object in our R-band image with a measured PanStarr magnitude is at rMeanPSFMag=22.2.
We acknowledge the excellent support from Observatoire de Haute-Provence, in particular Jean Balcaen.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35384.
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TITLE: GCN CIRCULAR
NUMBER: 35383
SUBJECT: GRB 231216A: GIT optical upper limit
DATE: 23/12/16 22:30:41 GMT
FROM: Vishwajeet Swain at IIT Bombay <vishwajeet.s(a)iitb.ac.in>
R. Sharma, V. Swain, V. Bhalerao (IIT Bombay), S. Barway, G. C. Anupama (IIA), K. Angail (IAO)
We observed the field of GRB 231216A detected by Swift (Sbarrato et al., GCN Circ. 35378) with 0.7m GROWTH-India Telescope (GIT). The observations started at 18:59:01.9 UT on 2023-12-16, i.e., 23 minutes after the BAT trigger. We obtained the multiple exposures of 100 and 300 sec in the g' and r' filters. In our stacked images, we did not detect the afterglow within the Swift-XRT position. The obtained upper limits follow as:
JD (mid) | t_mid-t0 (hours)| Filter | Exposure (s) | Limiting Magnitude (5 sigma) |
2460295.3278711 | 1.27 | r' | 5100 (stacked) | 22.0 |
2460295.3648310 | 2.16 | g' | 1500 (stacked) | 21.0 |
Our results are consistent with the upper limits reported by Global MASTER-Net (Lipunov et al., GCN Circ. 35379), BOOTES-2/TELMA (Hu et al., GCN Circ. 35381) and NOT (Malesani et al., GCN Circ. 35382). The magnitudes are calibrated against PanSTARRS DR1 (Chambers et al., 2016) and not corrected for Galactic extinction.
The GROWTH India Telescope (GIT; Kumar et al. 2022) is a 70-cm telescope with a 0.7-degree field of view, set up by the Indian Institute of Astrophysics (IIA) and the Indian Institute of Technology Bombay (IITB) with funding from DST-SERB and IUSSTF. It is located at the Indian Astronomical Observatory (Hanle), operated by IIA. We acknowledge funding by the IITB alumni batch of 1994, which partially supports the operations of the telescope. Telescope technical details are available at https://sites.google.com/view/growthindia/.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35383.
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TITLE: GCN CIRCULAR
NUMBER: 35382
SUBJECT: GRB 231216A: NOT optical upper limits
DATE: 23/12/16 22:12:21 GMT
FROM: Daniele B. Malesani at IMAPP / Radboud University <d.malesani(a)astro.ru.nl>
Daniele B. Malesani (DAWN/NBI and Radboud Univ.), Jacco H. Terwel (TCD and NOT), Benjamin N. Hauptmann (DTU Space and NOT) report on behalf of a larger collaboration:
We observed the position of GRB 231216A (Sbarrato et al., GCN 35378) using the Nordic Optical Telescope equipped with the ALFOSC images. Observations were carried out in the SDSS r and z filters, with an exposure time of 4x200 s in each filter. The delivered seeing in the combined images was around 1.5", and some calima affected the sky transparency.
Within (or near) the current XRT error circle, we detect no new objects down to magnitudes r > 23.5 and z > 21.5 (both AB), with mean times 2.25 and 2.44 hr after the trigger, respectively.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35382.
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TITLE: GCN CIRCULAR
NUMBER: 35381
SUBJECT: GRB 231216A: BOOTES-2/TELMA optical upper limit
DATE: 23/12/16 20:47:29 GMT
FROM: Youdong HU at IAA-CSIC <huyoudong072(a)hotmail.com>
Y.-D. Hu, 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 231216A by Swift (Sbarrato et al., GCNC 35378), the 0.6m BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain) automatically pointed to the burst position on Dec. 16 at 18:41:57 UT (i.e. ~51 s after notice, 5.3 min after trigger). In the co-added image (28 x 10 s, clear filter), no optical afterglow is detected within the XRT position down to 20.0 mag, which is consistent with both reports from UVOT (Sbarrato et al., GCNC 35378) and MASTER (Lipunov et al. GCNC 35379).
We thank the staff at IHSM/UMA-CSIC La Mayora for their excellent support.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35381.
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TITLE: GCN CIRCULAR
NUMBER: 35380
SUBJECT: GRB 231215A: GRBAlpha detection
DATE: 23/12/16 19:56:14 GMT
FROM: Marianna Dafčíková at Masaryk University <500025(a)mail.muni.cz>
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, 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 231215A (Swift/BAT detection: GCN 35343; Fermi/GBM detection: GCN 35344; AstroSat detection: GCN 35352; AGILE detection: GCN 35361; CALET/CGBM detection: GCN 35368; Konus/Wind detection: GCN 35377; INTEGRAL/SPI-ACS peak detection at 2023-12-15 ~09:47:26 UT) was observed by the GRBAlpha 1U CubeSat (Pal et al. 2023, A&A, 677, 40; arXiv:2302.10048).
The detection was confirmed at the peak time 2023-12-15 09:47:27 UTC. The T90 duration measured by GRBAlpha is 16 s and the overall significance during T90 reaches 42 sigma.
The light curve obtained by GRBAlpha is available here: https://grbalpha.konkoly.hu/static/share/GRB231215A_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.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35380.
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TITLE: GCN CIRCULAR
NUMBER: 35378
SUBJECT: GRB 231216A: Swift detection of a burst
DATE: 23/12/16 18:56:07 GMT
FROM: Tullia Sbarrato at INAF-OAB <tullia.sbarrato(a)inaf.it>
T. Sbarrato (INAF-OAB), P. D'Avanzo (INAF-OAB), S. Dichiara (PSU),
M. Ferro (INAF-OAB), J.D. Gropp (PSU), S. Laha (GSFC/UMBC),
M. J. Moss (GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL),
B. Sbarufatti (INAF-OAB) and M. H. Siegel (PSU) report on behalf of
the Neil Gehrels Swift Observatory Team:
At 18:35:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 231216A (trigger=1202749). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 39.759, +33.596 which is
RA(J2000) = 02h 39m 02s
Dec(J2000) = +33d 35' 45"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a complex
structure with a duration of about 70 sec. The peak count rate
was ~2000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 18:37:53.1 UT, 131.1 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source located at RA, Dec 39.77287, 33.57671 which
is equivalent to:
RA(J2000) = 02h 39m 05.49s
Dec(J2000) = +33d 34' 36.2"
with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 80 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 8.36
x 10^20 cm^-2 (Willingale et al. 2013).
UVOT took a finding chart exposure of 250 seconds with the U filter starting
191 seconds after the BAT trigger. No credible afterglow candidate has been
found in the initial data products. The 2.7'x2.7' sub-image covers 33% of the
XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag.
Results from the list of sources generated on-board are not available at this
time. No correction has been made for the expected extinction corresponding to
E(B-V) of 0.081.
Burst Advocate for this burst is T. Sbarrato (tullia.sbarrato AT inaf.it).
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)
View this GCN Circular online at https://gcn.nasa.gov/circulars/35378.
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TITLE: GCN CIRCULAR
NUMBER: 35377
SUBJECT: Konus-Wind detection of GRB 231215A
DATE: 23/12/16 18:27:11 GMT
FROM: Dmitry Frederiks at Ioffe Institute <fred(a)mail.ioffe.ru>
D. Frederiks, A.Lysenko, A. Ridnaia, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The long, bright GRB 231215A (Swift detection: D'Avanzo et al., GCN 35343;
AstroSat CZTI detection: Navaneeth et al., GCN 35352;
CALET Gamma-Ray Burst Monitor detection: Cannady et al., GCN 35368;
AGILE detection: Verrecchia et al., GCN 35361;
Fermi GBM detection: Lesage et al., GCN 35369)
triggered Konus-Wind (KW) at T0=35239.795 s UT (09:47:19.795).
The burst light curve shows a single multi-peaked pulse,
which starts at ~T0-1 s, peaks at ~T0+9.5 s,
and has a total duration of ~25 s.
The emission is seen up to ~10 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB231215_T35239/
As observed by Konus-Wind, the burst had
a fluence of (1.02 ± 0.09)x10^-4 erg/cm^2 and
a 64-ms peak energy flux, measured from T0 + 28.352 s,
of (1.14 ± 0.12)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum (measured from T0 to T0+24.320 s)
is best fit in the 20 keV - 15 MeV range
by a GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.67 (-0.07,+0.08),
the high energy photon index beta = -2.49 (-0.43,+0.22),
the peak energy Ep = 612 (-63,+74) keV,
chi2 = 80/97 dof.
The spectrum near the peak count rate (measured from T0+6.400s to T0+9.984s)
is best fit in the 20 keV - 15 MeV range
by a GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -0.49 (-0.09,+0.09),
the high energy photon index beta = -3.07 (-2.04,+0.44),
the peak energy Ep = 582 (-54,+58) keV,
chi2 = 69/80 dof.
Assuming the redshift z=2.305 (Thoene et al., GCN 35373)
and a standard cosmology with H_0 = 67.3 km/s/Mpc, Omega_M = 0.315,
and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the burst isotropic energy release E_iso to (1.35 ± 0.12)x10^54 erg,
the isotropic peak luminosity L_iso to (4.93 ± 0.49)x10^53 erg/s,
the rest-frame peak energy of the time-integrated spectrum Ep,i,z to ~2023 keV,
and the rest-frame peak energy at the peak of the emission Ep,p,z to ~1924 keV.
With the obtained estimates, GRB 230818A is inside 68% prediction band for
both 'Amati' and 'Yonetoku' relations derived for the sample of >300 long
KW GRBs with known redshifts (Tsvetkova et al., 2017; Tsvetkova et al., 2021),
see http://www.ioffe.ru/LEA/GRBs/GRB231215_T35239/GRB231215A_rest_frame.pdf
All the quoted errors are estimated at the 68% confidence level.
All the presented results are preliminary.
View this GCN Circular online at https://gcn.nasa.gov/circulars/35377.
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