GRB170816A

This page lists all entries on GRB170816A in GRBweb

Summary Fermi GBM IPN GCN 21504 GCN 21517 GCN 21615 GCN 21630 GCN 21695

Summary table
Variable Value Source
GRB_name_Fermi GRB170816599
T0 14:23:03.891 UTC Fermi_GBM
ra 350.8417° IPN
decl 12.8500° IPN
pos_error 2.32e+00° IPN
T90 1.6 s Fermi_GBM
T90_error 0.143 s Fermi_GBM
T90_start 14:23:03.891 UTC Fermi_GBM
fluence 3.53e-06 erg/cm² Fermi_GBM
fluence_error 2.60e-08 erg/cm² Fermi_GBM
T100 1.6 s
GBM_located False
mjd 57981.59935059028 Fermi_GBM
Fermi GBM table
GRB_name_Fermi GRB170816599
trigger_name bn170816599
ra 350.8408°
decl 12.8531°
pos_error 4.03e+00°
datum 2017-08-16
t_trigger 14:23:03.955 UTC
T90 1.6 s
T90_error 0.143 s
T90_start 14:23:03.891 UTC
fluence 3.53e-06 erg/cm²
fluence_error 2.60e-08 erg/cm²
flux_1024 7.42e+00 erg/cm²/s
flux_1024_error 2.93e-01 erg/cm²/s
flux_1024_time -4.48e-01 erg/cm²/s
flux_64 2.66e+01 erg/cm²/s
flux_64_error 1.55e+00 erg/cm²/s
IPN table
GRB_name GRB170816A
ra 350.8417°
decl 12.8500°
pos_error 2.32e+00°
GCN 21504 table
GRB_name GRB170816A
GCN_number 21504
Detection_method Fermi GBM Det
t_trigger 14:23:03.960 UTC
ra 351.4000°
decl 19.1000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21504 SUBJECT: GRB 170816A: Fermi GBM detection DATE: 17/08/17 10:04:36 GMT FROM: Andreas von Kienlin at MPE O.J. Roberts (USRA), C. Meegan (UAH) and A. von Kienlin (MPE) report on behalf of the Fermi GBM Team: "At 14:23:03.96 UT on 16 August 2017, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 170816A (trigger 524586188 / 170816599). The on-ground calculated location, using the GBM trigger data, is RA = 351.4, DEC = +19.1, with an uncertainty of 2.2 degrees (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 initial angle from the Fermi LAT boresight to the GBM best location is 97 degrees. This burst was also independently detected by INTEGRAL SPI-ACS. The GBM triggered on an initial bright peak that was followed ~1 s later by a slightly dimmer peak. The total duration (T90) was about 2 s (50-300 keV). The time-averaged spectrum from T0-0.064 to T0+1.600 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.5 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 1250.00 +/- 150.00 keV The event fluence (10-1000 keV) in this time interval is (4.0+/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.45 s in the 10-1000 keV band is 7.3 +/- 0.3 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 21517 table
GRB_name GRB170816A
GCN_number 21517
Detection_method IPN Triangulation
t_trigger 14:23:04 UTC
ra 350.8410°
decl 12.8530°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21517 SUBJECT: IPN Triangulation of GRB 170816A (short/hard) DATE: 17/08/17 19:28:28 GMT FROM: Anna Kozlova at Ioffe Institute A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, K. Hurley, on behalf of the IPN, V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein, on behalf of the Fermi GBM team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and S. Barthelmy, J. Cummings, H. Krimm, and D. Palmer, on behalf of the Swift-BAT team, report: A short-duration, hard-spectrum GRB 170816A was detected by by Fermi (GBM; Roberts et al., GCN 21504), Konus-Wind, INTEGRAL (SPI-ACS), and Swift (BAT), so far, at about 51784 s UT (14:23:04). The burst was outside the coded field of view of the BAT. We have triangulated it to a preliminary, 3 sigma error box whose coordinates are: --------------------------------------------- RA(2000), deg Dec(2000), deg --------------------------------------------- Center: 350.841 (23h 23m 22s) +12.853 (+12d 51' 11") Corners: 349.856 (23h 19m 25s) +13.372 (+13d 22' 19") 352.036 (23h 28m 09s) +12.535 (+12d 32' 07") 351.782 (23h 27m 08s) +12.294 (+12d 17' 38") 349.591 (23h 18m 22s) +13.118 (+13d 07' 06") --------------------------------------------- The error box area is 2650 sq. arcmin, and its maximum dimension is 2.45 deg (the minimum one is 19 arcmin). The Sun distance was 144 deg. This box may be improved. A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB170816_T51789/IPN The Konus-Wind time history and spectrum will be given in a forthcoming GCN Circular.
GCN 21615 table
GRB_name GRB170816A
GCN_number 21615
Detection_method CALET
Circular_text TITLE: GCN CIRCULAR NUMBER: 21615 SUBJECT: GRB 170816A CALET Gamma-Ray Burst Monitor detection DATE: 17/08/20 11:38:56 GMT FROM: Takanori Sakamoto at AGU W. Ishizaki (ICRR), A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama, Y. Yamada, A. Tezuka, S. Matsukawa (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), M. L. Cherry (LSU), S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena) and the CALET collaboration: The long-duration GRB 170816A (Roberts et al., GCN Circ. 21504; Kozlova et al., GCN Circ. 21517) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 14:23:03.81 on 16 August 2017. The burst signal was clearly seen by the SGM instrument. The light curve of the SGM shows a bright single peak. The emission starts at T+0.1 sec, peaks at T+0.3 sec and ends at T+0.5 sec. The T90 duration measured by the SGM data is 0.25 +- 0.13 sec (40-1000 keV). The light curve is available at http://cgbm.calet.jp/cgbm_trigger/flight/1186927993/ The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
GCN 21630 table
GRB_name GRB170816A
GCN_number 21630
Detection_method Konus-Wind Det
t_trigger 14:23:09.108 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 21630 SUBJECT: Konus-Wind observation of GRB 170816A DATE: 17/08/21 10:56:48 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report: The short/hard GRB 170816A (Fermi GBM detection: Roberts et al., GCN 21504; IPN triangulation: Kozlova et al., GCN 21517; CALET Gamma-Ray Burst Monitor detection: Ishizaki et al., GCN 21615) triggered Konus-Wind at T0=51789.108 s UT (14:23:09.108). The burst light curve shows a bright, multi-peaked pulse which started at ~T0-0.064 s and had a total duration of ~0.3 s. A weaker count rate increase is also visible around ~T0+1.5 s The emission is seen up to ~10 MeV. As observed by Konus-Wind, the burst had a fluence of 6.6(-2.4, +4.2)x10^-6 erg/cm2 and a 16-ms peak energy flux, measured from T0+0.175s of (5.9 ± 0.7)x10^-5 erg/cm2 (both in the 20 keV - 10 MeV energy range). The time-integrated spectrum (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 15 MeV range by a cutoff power-law (CPL) function with the following model parameters: the photon index alpha = -0.87(-0.36,+0.60), and the peak energy Ep = 1156(-556,+1626) keV, chi2 = 86/98 dof. Fitting this spectrum with the GRB (Band) function yields the same alpha and Ep, and an upper limit on beta of -1.9, chi2 = 86/97 dof. The spectrum near the peak count rate (measured from T0+0.128 to T0+0.192 s) is best fit in the 20 keV - 15 MeV range by the CPL function with the following model parameters: the photon index alpha = +0.49(-0.50,+0.66), and the peak energy Ep = 1339(-285,+462) keV, chi2 = 17/19 dof. Fitting this spectrum with the GRB (Band) function yields the same alpha and Ep, and an upper limit on beta of -1.6, chi2 = 17/18 dof. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB170816_T51789/ All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary. [GCN OPS NOTE(21aug17): Per R.Hamberg's request, in the 2ndline the Hamburg citation was changed to Roberts.]
GCN 21695 table
GRB_name GRB170816A
GCN_number 21695
Detection_method INTEGRAL
ra 41.0700°
decl -45.4900°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21695 SUBJECT: LIGO/Virgo G297595: INTEGRAL pointed follow-up observations DATE: 17/08/25 14:33:57 GMT FROM: Volodymyr Savchenko at APC,Paris V. Savchenko (ISDC, University of Geneva, CH) on behalf of the INTEGRAL group: C. Ferrigno, E. Bozzo ((ISDC, University of Geneva, CH), E. Kuulkers (ESTEC/ESA, The Netherlands), S. Mereghetti (IASF-Milano, Italy), T. J.-L. Courvoisier (ISDC, University of Geneva, CH) J. Chenevez, S. Brandt (DTU - Denmark) R. Diehl (MPE-Garching, Germany) L. Hanlon (UCD, Ireland) P. Laurent (APC, Saclay/CEA, France), D. Gotz (DRF/Irfu/DAp Saclay/CEA) J.P. Roques, E. Jourdain (IRAP, France) P. Ubertini, A. Bazzano, J. Rodi (IAPS-Roma, Italy) A. Lutovinov, R. Sunyaev (IKI, Russia) INTEGRAL is an observatory with multiple instruments: a gamma-ray spectrometer (20 keV -4 MeV, SPI), an imager (15 keV - 2 MeV, IBIS), an X-ray monitor (3-25 keV, JEM-X), and an optical monitor (V band, OMC). Our group requested and obtained pointed follow-up observations of the LIGO/Virgo candidate BBH merger G297595 (GCN 21474). The INTEGRAL follow-up observation was centered on RA=41.07 Dec=-45.49, close to the peak of the LIGO/Virgo localization probability, taking into account observational constrains. This observation spanned from 2017-08-16 at 10:04 to 2017-08-17 at 18:19 (starting about 47 hours after the LIGO/Virgo event), with a maximum on-source time of 97.5 ks (depending on the instrument). IBIS and SPI observed more than 92% of the of LIGO/Virgo localization in the combined observation mosaic. JEM-X covered about 79%, owing to its smaller Field of View. INTEGRAL provides the most stringent constraint on any possible emission associated with G297595, above 80 keV. We searched IBIS/ISGRI and JEM-X data for new point sources in the whole 90% LIGO/Virgo localization region, and did not find any. We set the following 3-sigma upper limits for the average flux: JEM-X: 3-10 keV: 2.0 mCrab (3.2e-11 erg/cm2/s ) 10-25 keV: 1.0 mCrab (1.1e-11 erg/cm2/s ) ISGRI: 20-80 keV: 3.3 mCrab (4.9e-11 erg/cm2/s) 80-300 keV: 13.1 mCrab (1.5e-10 erg/cm2/s) In the case of ISGRI (JEM-X), 82% (59%) of the of LIGO/Virgo localization is covered with sensitivity no more than factor two worse than the best. During these observation online INTEGRAL/IBAS system identified several weak triggers. After offline inspection, we consider these triggers unrelated noise. INTEGRAL/IBAS online search in the SPI-ACS identified a bright GRB170816A on 2017-08-16 at 14:22:58. The location of this GRB is inconsistent with the LIGO/Virgo 90% localization (GCN 21504, 21517). Finally, the BNS merger G298048 (GCN 21509, 21513) candidate counterpart (GRB 170817A, GCN 21506, 21520) was detected in the INTEGRAL data during this observation, as reported in GCN 21507. We have also inspected PICsIT spectral-timing data (200 - 2600 keV) and did not find any evidence for significant variability. Further analysis is ongoing. We acknowledge the essential support by the teams at ESAC and ESOC for the scheduling of this follow-up observation.