GRB160625B

This page lists all entries on GRB160625B in GRBweb

Summary Fermi GBM IPN Fermi LAT GCN 19580 GCN 19581 GCN 19582 GCN 19585 GCN 19586 GCN 19587 GCN 19588 GCN 19589 GCN 19599 GCN 19600 GCN 19601 GCN 19602 GCN 19603 GCN 19604 GCN 19605 GCN 19606 GCN 19610 GCN 19611 GCN 19612 GCN 19615 GCN 19616 GCN 19617 GCN 19619 GCN 19620 GCN 19640 GCN 19642 GCN 19651 GCN 19680 GCN 19683

Summary table
Variable Value Source
GRB_name_Fermi GRB160625945
T0 22:40:15.280 UTC Fermi_LAT
ra 308.5979° Fermi_LAT
decl 6.9189° Fermi_LAT
pos_error 1.39e-04° Fermi_LAT
T90 453.385 s Fermi_GBM
T90_error 0.572 s Fermi_GBM
T90_start 22:43:24.726 UTC Fermi_GBM
fluence 6.43e-04 erg/cm² Fermi_GBM
fluence_error 1.85e-07 erg/cm² Fermi_GBM
redshift 1.4060
T100 642.831 s
GBM_located False
mjd 57564.944621296294 Fermi_LAT
Fermi GBM table
GRB_name_Fermi GRB160625945
trigger_name bn160625945
ra 308.5971°
decl 6.9197°
pos_error 3.98e+00°
datum 2016-06-25
t_trigger 22:40:16.275 UTC
T90 453.385 s
T90_error 0.572 s
T90_start 22:43:24.726 UTC
fluence 6.43e-04 erg/cm²
fluence_error 1.85e-07 erg/cm²
flux_1024 2.17e+02 erg/cm²/s
flux_1024_error 9.87e-01 erg/cm²/s
flux_1024_time 1.89e+02 erg/cm²/s
flux_64 2.28e+02 erg/cm²/s
flux_64_error 4.09e+00 erg/cm²/s
IPN table
GRB_name GRB160625B
ra 308.2667°
decl 6.9000°
pos_error 5.00e-02°
redshift 1.4060
Fermi LAT table
GRB_name_Fermi GRB160625945
GRB_name GRB160625B
MET 488587219.28
datum 2016-06-25
t_trigger 22:40:15.280 UTC
ra 308.5979°
decl 6.9189°
pos_error 1.39e-04°
GCN 19580 table
GRB_name GRB160625B
GCN_number 19580
Detection_method Fermi LAT Det
t_trigger 22:43:24 UTC
ra 308.3000°
decl 6.9000°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19580 SUBJECT: GRB 160625B: Fermi-LAT detection of a bright burst DATE: 16/06/26 00:23:32 GMT FROM: Judith Racusin at GSFC F. Dirirsa (U. Johannesburg), J. Racusin (NASA/GSFC), J. McEnery (NASA/GSFC), and R. Desiante (INFN Torino) report on behalf of the Fermi-LAT team: At 22:43:24 on June 25, 2016, Fermi/LAT detected a sharp increase in the rate of high-energy photons, resulting in an onboard trigger on GRB 160625B. Fermi/GBM triggered on this object two separate times (160625945/488587220, 160625952/488587880), with emission evident between triggers, including the time at which LAT triggered. Note that all of these triggers are distinct from the Swift/BAT trigger on GRB160625A (Maselli et al., GCN 19577) that occurred 15 seconds after the first GBM trigger, and was occulted by the Earth to Fermi at the time, and >100 degrees away on the sky. The onboard location is: RA, Dec = 308.3, +6.9 (J2000) with an error radius of 0.5 deg (90% containment, systematic error only). This was 12.3 deg from the LAT boresight at the time of the LAT trigger. We anticipate providing a refined location within the next 8 hours when the LAT science data for this burst is downlinked and processed. A Swift TOO request has been approved, and given the unusual nature of this trigger, a Fermi TOO will extended the pointed-mode observations to T0+24 hours beyond the initial autonomous repoint. The Fermi-LAT point of contact for this burst is Feraol Dirirsa (fdirirsa@uj.ac.za). The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.
GCN 19581 table
GRB_name GRB160625B
GCN_number 19581
Detection_method Fermi GBM Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 19581 SUBJECT: GRB 160625B: Fermi GBM initial observations DATE: 16/06/26 00:53:38 GMT FROM: Eric Burns at U of Alabama E. Burns (UAH) reports on behalf of the Fermi GBM Team: "At 22:40:16.28 UT on 25 June 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160625B for the first time (trigger 488587220 / 160625945). The trigger resulted in an Autonomous Repoint Request (ARR) by the GBM Flight Software owing to the high peak flux of the GRB. This ARR was accepted and the spacecraft slewed to the GBM in-flight location. The initial angle from the Fermi LAT boresight to the GBM ground location is 40 degrees. At 22:43:24.82 the Fermi LAT triggered on a bright pulse from the same GRB (Dirirsa et al. 2016, GCN 19580). Owing to the ARR the initial angle from the Fermi LAT boresight to the LAT position at LAT trigger time was 12 degrees. At 22:51:16.03 GBM triggered again on GRB 160625B (trigger 488587880 / 160625952). GRB 160625B is distinct from the Swift BAT GRB 160625A (Maselli et al. 2016, GCN 19577). The GBM light curve consists of multiple peaks over approximately 700 seconds. The first peak is soft with a duration of about 1 second. The main peak, corresponding to the LAT trigger, is about 25 seconds long and is very hard. The peak that triggered GBM for the second time is about 30 seconds long and soft. Standard GBM temporal and spectral analysis is awaiting downlink of the full dataset and will be reported when available."
GCN 19582 table
GRB_name GRB160625B
GCN_number 19582
Detection_method Swift Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 19582 SUBJECT: GRB 160625B: Tiled Swift observations DATE: 16/06/26 01:18:16 GMT FROM: Phil Evans at U of Leicester P. A. Evans (U. Leicester) reports on behalf of the Swift team: Swift has initiated a series of observations, tiled on the sky, of the Fermi/LAT GRB 160625B. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00056 Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. The probability of finding serendipitous sources, unrelated to the Fermi/LAT event is high: any X-ray source considered to be a probable afterglow candidate will be reported via a GCN Circular after manual consideration. Details of the XRT automated analysis methods are detailed in Evans et al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8). This circular is an official product of the Swift-XRT team.
GCN 19585 table
GRB_name GRB160625B
GCN_number 19585
Detection_method Swift-XRT Other
ra 308.5969°
decl 6.9196°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19585 SUBJECT: GRB 160625B: Swift-XRT afterglow detection DATE: 16/06/26 06:54:13 GMT FROM: Antonino D'Ai at IASF-PA A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), D.N. Burrows (PSU), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team: Swift-XRT has performed follow-up observations of the Fermi/LAT-detected burst GRB 160625B (Dirirsa et al. GCN Circ. 19580) in a series of observations tiled on the sky. The total exposure time is 2.7 ks, distributed over 8 tiles; the maximum exposure at a single sky location was 1.1 ks. The data were collected between T0+9.6 ks and T0+10.0 ks, and are entirely in Photon Counting (PC) mode. An uncatalogued X-ray source is detected and is above the RASS limit, and is therefore likely the GRB afterglow. The position of this source is RA, Dec=308.5969, +6.9196 which is equivalent to: RA (J2000): 20:34:23.25 Dec(J2000): +06:55:10.5 with an uncertainty of 3.8 arcsec (radius, 90% confidence). This position is 19.7 arcmin from the Fermi/LAT position. The light curve can be modelled with a power-law decay with a decay index of alpha=3.156 (+0.011, -2.764). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 2.09 (+0.20, -0.19). The best-fitting absorption column is 1.6 (+/-0.6) x 10^21 cm^-2, in excess of the Galactic value of 9.8 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.1 x 10^-11 (4.3 x 10^-11) erg cm^-2 count^-1. A summary of the WT-mode spectrum is thus: Total column: 1.6 (+/-0.6) x 10^21 cm^-2 Galactic foreground: 9.8 x 10^20 cm^-2 Excess significance: 1.8 sigma Photon index: 2.09 (+0.20, -0.19) If the light curve continues to decay with a power-law decay index of 3.156, the count rate at T+24 hours will be 6.1 x 10^-3 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.9 x 10^-13 (2.6 x 10^-13) erg cm^-2 s^-1. The results of the XRT-team automatic analysis of the likely afterglow are at http://www.swift.ac.uk/xrt_products/TILED_GRB00056/index_1.php. The results of the full analysis of the tiled XRT observations are available at http://www.swift.ac.uk/xrt_products/TILED_GRB00056. This circular is an official product of the Swift-XRT team.
GCN 19586 table
GRB_name GRB160625B
GCN_number 19586
Detection_method Fermi LAT Other
ra 308.5600°
decl 6.9300°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19586 SUBJECT: GRB 160625B: Fermi-LAT refined analysis DATE: 16/06/26 07:55:38 GMT FROM: Judith Racusin at GSFC F. Dirirsa (U. Johannesburg), G. Vianello (Stanford), J. Racusin (NASA/GSFC), and M. Axelsson (KTH Stockholm) report on behalf of the Fermi-LAT team: We report the on-ground localization and analysis of GRB 160625B, which triggered the LAT onboard (Dirisa et al., GCN 19580). All times are relative to the initial GBM trigger (Burns et al, GCN 19581). The best LAT on-ground location is found to be: RA, Dec = 308.56, 6.93 deg (J2000) with an error radius of 0.06 deg (90 % containment, statistical error only). This is fully compatible with the position of the afterglow detected by Swift/XRT (Melandri et al., GCN 19585). This was 42 deg from the LAT boresight at the time of the GBM trigger and triggered an autonomous repoint of the spacecraft. More than 300 photons were detected above 100 MeV. The LAT emission became detectable during the second bright pulse observed by GBM at ~T0+181 s. The highest-energy photon is a 15 GeV event which is observed ~345 seconds after the GBM trigger. The GRB was detectable by the LAT up to ~1 ks after the trigger. Data are still being collected, and pointed mode observations are continuing to maximize exposure to the GRB location. The Fermi-LAT point of contact for this burst is Feraol Dirirsa (fdirirsa@uj.ac.za ). The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.
GCN 19587 table
GRB_name GRB160625B
GCN_number 19587
Detection_method Fermi GBM Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 19587 SUBJECT: GRB 160625B: Fermi GBM refined analysis DATE: 16/06/26 08:01:15 GMT FROM: Eric Burns at U of Alabama E. Burns (UAH) reports on behalf of the Fermi GBM Team: "We report temporal and spectral analysis on GRB 160625B, covering all three Fermi trigger times (LAT trigger 488587408 / 160625947 GBM triggers 488587220 / 160625945 and 488587880 / 160625952). All times are relative to the first GBM trigger time. The GBM light curve consists of multiple peaks with a total duration (T90) of about 460 s (50-300 keV). The 1.024-sec peak photon flux of the main peak measured starting from T0+188.707 s in the 10-1000 keV band is 167 +/- 1 ph/s/cm^2. The soft peak that initially triggered GBM is about 1 second long. The time-averaged spectrum from T0+0.002 s to T0+1.056 s is well fit by a power law function with an exponential high-energy cutoff. The power law index is -0.2 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 68 +/- 1 keV. The event fluence (10-1000 keV) in this time interval is (1.65 +/- 0.03)E-06 erg/cm^2. The main peak that triggered the LAT is about 25 seconds long. The time-averaged spectrum from T0+187.427 s to T0+212.003 s is well fit by a Band function with Epeak = 657 +/- 5 keV, alpha = -0.74 +/- 0.00, and beta = 2.36 +/- 0.01. The event fluence (10-1000 keV) in this time interval is (5.00 +/- 0.01)E-04 erg/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 19588 table
GRB_name GRB160625B
GCN_number 19588
Detection_method Swift-XRT Other
ra 308.5979°
decl 6.9189°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19588 SUBJECT: GRB 160625B: RATIR Optical and NIR Afterglow Detection DATE: 16/06/26 08:18:57 GMT FROM: Eleonora Troja at GSFC Eleonora Troja (GSFC), Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (GSFC/STScI), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report: We observed the field of the Fermi LAT GRB 160625B (Dirirsa, et al., GCN 19580) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2016/06 26.30 to 2016/06 26.32 UTC (8.53 to 9.02 hours after the LAT trigger), obtaining a total of 0.36 hours exposure in the r and i bands and 0.15 hours exposure in the Z, Y, J and H bands. We detect a bright, fading and uncatalogued source at the edge of the Swift-XRT error circle (Melandri, et al., GCN 19585), at a position RA, Dec = 20:34:23.50, +6:55:8.1 (J2000, +/-0.5"). In comparison with the USNO-B1 and 2MASS catalogs, we obtain the following values: r = 18.28 +/- 0.01 i = 18.08 +/- 0.01 Z = 17.95 +/- 0.01 Y = 17.78 +/- 0.01 J = 17.77 +/- 0.02 H = 17.65 +/- 0.02 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. Further observations are on-going. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
GCN 19589 table
GRB_name GRB160625B
GCN_number 19589
Detection_method Swift-UVOT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 19589 SUBJECT: GRB 160625B: Swift/UVOT Detection DATE: 16/06/26 11:15:45 GMT FROM: Samantha Oates at MSSL GRB 160625B: Swift/UVOT Detection S. R. Oates (U. Warwick) and A. D'A (INAF-IASFPA) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 160625B 9616 s after the LAT trigger (Dirirsa et al., GCN Circ. 19580). A source consistent with the RATIR position (Troja et al. GCN Circ. 19588) and the edge of the XRT position (Melandri et al. GCN Circ. 19585) is detected in the initial UVOT exposures. Preliminary detections using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag u 9616 9978 353 16.41 +/- 0.04 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.12 in the direction of the burst (Schlegel et al. 1998).
GCN 19599 table
GRB_name GRB160625B
GCN_number 19599
Detection_method MITSuME
Circular_text TITLE: GCN CIRCULAR NUMBER: 19599 SUBJECT: GRB 160625B: MITSuME Ishigakijima Optical Observation DATE: 16/06/27 02:51:23 GMT FROM: Daisuke Kuroda at OAO/NAOJ D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ), K. Yanagisawa (OAO, NAOJ), S.Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto) and N. Kawai(Tokyo Tech) report on behalf of the MITSuME and OISTER collaboration: We observed the field of GRB 160625B (Dirirsa et al., GCNC 19580; Melandri et al., GCNC 19585) with the optical three color (g', Rc and Ic) CCD camera attached to the Murikabushi 1m telescope of Ishigakijima Astronomical Observatory. The observation started on 2016-06-26 14:03:44 UT (~15.3 h after the burst). We detected the previously reported afterglow (Troja et al., GCNC 19588) in in all the three bands. The photometric results of the OT are listed below. We used GSC2.3 catalog for flux calibration. #T0+[day] MID-UT T-EXP[sec] g' g'_e Rc Rc_e Ic Ic_e ------------------------------------------------------------------- 0.64273 14:08:57 540.0 19.16 0.10 18.59 0.05 18.08 0.10 0.73075 16:15:41 540.0 19.27 0.08 18.78 0.06 18.28 0.08 ------------------------------------------------------------------- T0+ : Elapsed time after the burst [day] T-EXP: Total Exposure time [sec]
GCN 19600 table
GRB_name GRB160625B
GCN_number 19600
Detection_method Optical
redshift 1.4060
Circular_text TITLE: GCN CIRCULAR NUMBER: 19600 SUBJECT: GRB 160625B: VLT/X-shooter redshift DATE: 16/06/27 09:50:38 GMT FROM: Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst D. Xu (NAOC/CAS), D. Malesani (DARK/NBI), J. P. U. Fynbo (DARK/NBI), N. R. Tanvir (Univ. Leicester), A. J. Levan (Univ. Warwick), D. A. Perley (DARK/NBI), report on behalf of a larger collaboration: We observed the optical afterglow of the Fermi GRB 160625B (Dirirsa et al., GCN 19580; Burns, GCN 19581; Troja et al., GCN 19588) with the ESO VLT UT2 (Kueyen) equipped with the X-shooter spectrograph. Observations started on 2016 June 27.19 UT (1.25 days after the Fermi trigger) and consisted of 4 spectra by 600 s each, covering the wavelength range 3500-20000 AA. The afterglow is well detected in the acquisition image with R ~ 19.1 +- 0.3, where the large error is due to scatter in the USNO magnitudes used as reference, and the r versus R filter transformation. The continuum trace is well detected in our exposures, down to ~3100 AA. The lack of any drop sets an upper limit to the redshift z < 1.55. A number of superimposed absorption features are visible; among others, we detect Mg I, Mg II, Fe II, C IV, Si IV, O I, Si II, Zn II, Al II, and Al III, all at a common redshift z = 1.406, which we conclude to be the redshift of GRB 160625B. We also detect an intervening Mg II absorption system at z = 1.319. At z = 1.406, the fluence in the 10-1000 keV Fermi band (Burns, GCN 19587) corresponds to an isotropic-equivalent energy of ~2.5*10^54 erg. We acknowledge excellent support from the ESO observing staff in Paranal, in particular Juan Carlos Munoz, Elizabeth (Liz) Bartlett, Dimitri Gadotti and Francisco Caceres.
GCN 19601 table
GRB_name GRB160625B
GCN_number 19601
Detection_method Optical
redshift 1.4100
Circular_text TITLE: GCN CIRCULAR NUMBER: 19601 SUBJECT: GRB 160625B: TNG redshift confirmation DATE: 16/06/27 09:51:06 GMT FROM: Valerio D'Elia at ASDC V. DElia (INAF-OAR/ASI-ASDC), A. Melandri (INAF-OAB) and D. Malesani (DARK/NBI) report on behalf of the CIBO collaboration: We observed the afterglow of GRB 160625B (Dirirsa et al., GCN 19580) with the TNG equipped with DOLORES and the LR-B grism. The spectrum was acquired on 2016-06-26 and covers the range between 3000 and 7800 AA. The observation consisted of 2400 s exposure, starting at 23:04:20.836 (24 hr after the trigger). The optical counterpart is clearly detected in the acquisition images with a magnitude r = 19.0 +/- 0.3 at the position reported by Troja et al. (GCN 19588) and Oates and D'A (GCN 19589). The spectrum shows a clear continuum. We detect absorption features consistent with Mg I, Mg II, Mn II and Fe II lines a redshift of z = 1.41 +/- 0.01, thus confirming the redshift reported by Xu et al. (GCN 19600). We thanks the TNG staff for excellent support, in particular Luca di Fabrizio and Albar Garcia.
GCN 19602 table
GRB_name GRB160625B
GCN_number 19602
Detection_method Swift-BAT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 19602 SUBJECT: GRB 160625B: RATIR Optical and NIR Observations DATE: 16/06/27 14:12:33 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Alan M. Watson (UNAM), Eleonora Troja (GSFC), Nat Butler (ASU), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (GSFC/STScI), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), José A. de Diego (UNAM), Leonid Georgiev (UNAM), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report: We observed the field of the Fermi LAT GRB 160625B (Dirirsa, et al., GCN 19580) with the Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the Observatorio Astronómico Nacional on Sierra San Pedro Mártir from 2016/06 27.36 to 2016/06 27.47 UTC (33.89 to 36.56 hours after the BAT trigger), obtaining a total of 1.73 hours exposure in the r and i bands and 0.73 hours exposure in the Z, Y, J, and H bands. We detect the afterglow reported by Troja et al. (GCN Circ. 19588) and, in comparison with the USNO-B1 and 2MASS catalogs, obtain the following magnitudes: r = 19.63 +/- 0.01 i = 19.52 +/- 0.01 Z = 19.34 +/- 0.02 Y = 19.17 +/- 0.02 J = 19.11 +/- 0.02 H = 18.98 +/- 0.03 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. The afterglow has faded by about 1.20 magnitude in all bands compared to our earlier epoch, confirming the fading seen during the first epoch. The fading is consistent with a temporal index of -0.90. More observations are planned. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir. [GCN OPS NOTE(27jun16): Per author's request, the GRB name in the Title was changed from "A" to "B". The name in the text was/is correct.]
GCN 19603 table
GRB_name GRB160625B
GCN_number 19603
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19603 SUBJECT: GRB 160625B: Mini-MegaTORTORA detection of bright optical flash simultaneous with LAT event DATE: 16/06/27 15:37:31 GMT FROM: Sergey Karpov at SAO RAS S.Karpov, G.Beskin (SAO RAS and Kazan Federal University, Russia), S.Bondar, E.Ivanov, E.Katkova, N.Orekhova, A.Perkov (OJS RPC PSI, Russia), A.Biryukov (SAI MSU and Kazan Federal University, Russia), V.Sasyuk (Kazan Federal University, Russia) The on-sky position of GRB 160625B (Dirirsa et al., GCN Circ. 19580) has been observed by Mini-MegaTORTORA nine-channel wide-field monitoring system with high temporal resolution (http://mmt.favor2.info) before, during and just after the LAT trigger time (T0 = 2016-06-25 22:43:24). Mini-MegaTORTORA reacted to Fermi GBM trigger 488587220 and started observing its error box at 2016-06-25 22:41:07, 52 seconds after GBM trigger and 136 seconds before LAT trigger. Due to large size of error box, the observations have been performed in "widefield+deep" regime, with channels simultaneously covering ~30x30 deg field of view with 30 s exposures in white light to achieve deepest detection limit. The system acquired 20 frames in such regime, covering time interval from T0-136 to T0+466 s. The system detected a bright optical flash on a frame coincident with LAT trigger time (T0-15.9 - T0+14.1 s) at position reported by Troja et al. (GCN Circ. 19588), with a magnitude of about V=8.8 mag. Next frame displayed a slight rebrightening of about 0.1 mag, and then the light curve followed nearly smooth power-law decay with slope of about -1.6, down to V=12.2 at last acquired frame. The images acquired prior to LAT trigger do not display any object at that position down to about V=13.5 mag. The system also reacted to second GBM trigger 488587880 with slightly different coordinates, and due to large field of view again covered the position of a transient, acquiring 20 more frames from T0+1691 to T0+2264 s. No object is seen in these frames down to about V=13.5 mag. Snapshots of a frames from first follow-up (20 arcmin fields around the transient) is available at http://vo.astronet.ru/~karpov/grb160625b_mosaic.png Further analysis and calibration of the data is ongoing. Mini-MegaTORTORA belongs to Kazan Federal University and is located at Special Astrophysical Observatory near Russian 6-m telescope.
GCN 19604 table
GRB_name GRB160625B
GCN_number 19604
Detection_method Konus-Wind Det
t_trigger 22:40:19.875 UTC
redshift 1.4060
Circular_text TITLE: GCN CIRCULAR NUMBER: 19604 SUBJECT: Konus-Wind observation of GRB 160625B DATE: 16/06/27 16:30:09 GMT FROM: Dmitry Frederiks at Ioffe Institute D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, P. Oleynik, M. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, and T. Cline on behalf of the Konus-Wind team, report: The long-duration, extremely bright GRB 160625B (Fermi-LAT detection: Dirirsa et al., GCN Circ. 19580; Fermi-GBM detection: Burns, GCN Circ. 19581) triggered Konus-Wind at T0=81619.875 s UT (22:40:19.875). The burst light curve starts, at ~T0-0.3 s, with a short soft initial pulse (precursor) which had a duration of about 1 s. The precursor is followed, starting at ~T0+180 s, by the main, extremely bright and spectrally-hard episode with a duration of about 40 s. This episode evolves into a weak emission traceable up to ~T0+680 s. The emission in the main episode is seen up to ~20 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB160625_T81619/ As observed by Konus-Wind, the burst had a fluence of 9.44(-0.16,+0.16)x10^-4 erg/cm2, and a 256-ms peak flux, measured from T0+188.928 s, of 1.26(-0.10,+0.10)x10^-4 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the initial pulse (measured from T0 to T0+8.448 s) is best fit in the 20 keV - 1 MeV range by a simple power law model with the photon index alpha = -2.34(-0.22,+0.25) (chi2 = 38/61 dof) The time-averaged spectrum of the main episode (measured from T0+180.480 to T0+229.632 s) is best fit in the 20 keV - 20 MeV range by the GRB (Band) model with the following parameters: the low-energy photon index alpha = -0.79(-0.02,+0.02), the high energy photon index beta = -2.25(-0.04,+0.04), the peak energy Ep = 554(-19,+20) keV (chi2 = 353/97 dof) The spectrum near the maximum count rate (measured from T0+188.928 to T0+189.184 s) is best fit in the 20 keV - 20 MeV range by the Band model with the following parameters: the low-energy photon index alpha = -0.77(-0.08,+0.10), the high energy photon index beta = -2.22(-0.25,+0.17), the peak energy Ep = 937(-179,+195) keV (chi2 = 62/67 dof) Assuming the redshift z=1.406 (Xu, et al., GCN Circ. 19600) and a standard cosmology model with H_0 = 70 km/s/Mpc, Omega_M = 0.27, and Omega_Lambda = 0.73, we estimate the following rest-frame parameters: the isotropic energy release E_iso is ~5.0x10^54 erg, the peak luminosity L_iso is ~1.6x10^54 erg/s, and the rest-frame peak energy of the time-integrated spectrum, Ep,i, is ~1.3 MeV. This Eiso is the highest one measured by Konus-Wind for more than 21 years of its GRB observations and, probably, the highest Eiso recorded for a GRB ever. All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN 19605 table
GRB_name GRB160625B
GCN_number 19605
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19605 SUBJECT: GRB 160625B: TSHAO optical observations DATE: 16/06/27 19:59:50 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Kusakin (Fesenkov Astrophysical Institute), P. Minaev (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 160625B (Dirirsa et al., GCN 19580; Burns et al. GCN 19581) with Zeiss-1000 (East) 1-m telescopes of Tien Shan Astronomical Observatory. We obtained several images in R filter starting on June 26 (UT) 19:39:18. We detect optical afterglow of GRB 160625B (Troja et al., GCN 19588; Oates et al., GCN 19589). Preliminary photometry of a combined image is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2016-06-26 19:39:18 0.91784 R 50*120 19.07 0.05 22.0 Photometry is based on nearby USNO-B1.0 stars USNO-B.1_id R2 0969-0608423 16.38 0969-0608416 16.28 0969-0608335 15.00 0969-0608366 16.05 0969-0608449 17.38 0969-0608443 16.78 0969-0608456 16.79 The GRB 160625B triggered Fermi LAT and GBM (Dirirsa et al., GCN 19580; Burns et al. GCN 19581), Konus-Wind (Svinkin et al. GCN 19604) and D. Kann (GCN 19579) reported about CALET and SPI-ACS/INTEGRAL trigger. A light curve of SPI-ACS/INTEGRAL can be found in http://grb.rssi.ru/GRB160625B/GRB160625B_API-ACS.png The SPI-ACS time profile of GRB 160625B consists of 3 episodes of total duration about 750 seconds and compatible with time profiles reported by GBM (Burns, GCN 19581) and Konus-Wind (Svinkin et al. GCN 19604).
GCN 19606 table
GRB_name GRB160625B
GCN_number 19606
Detection_method VLA Det
ra 308.5979°
decl 6.9189°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19606 SUBJECT: GRB 160625B: VLA Detection DATE: 16/06/27 20:43:24 GMT FROM: Kate Alexander at Harvard K. D. Alexander (Harvard), T. Laskar (NRAO / UC Berkeley), W. Fong (University of Arizona) and E. Berger (Harvard) report on behalf of a larger collaboration: We observed the Fermi/LAT GRB 160625B (Diririsa et al., GCN 19580) at multiple frequencies with the Karl G. Jansky Very Large Array (VLA) beginning 2016 June 27.28 UT (1.34 days after the burst). At a mean frequency of 9.8 GHz, we detect a radio source with a preliminary flux density of ~400 uJy at RA (J2000) = 20:34:23.507 +/- 0.003 Dec (J2000) = +06:55:07.89 +/- 0.03 consistent with the position of the optical afterglow (Troja et al., GCN 19588; Oates et al., GCN 19589) and the Swift/XRT position (Melandri et al., GCN 19585). Follow-up observations are planned. We thank the VLA staff for rapidly executing these observations.
GCN 19610 table
GRB_name GRB160625B
GCN_number 19610
Detection_method Fermi LAT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 19610 SUBJECT: GRB 160625B: 15 GHz detection from AMI DATE: 16/06/28 13:15:59 GMT FROM: Kunal Mooley at Oxford U K. P. Mooley, T. D. Staley, R. P. Fender (Oxford), G. E. Anderson (Curtin), T. Cantwell (Manchester), C. Rumsey, D. Titterington, S. H. Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods, P. Scott (Cambridge), K. Grainge, A. Scaife (Manchester) We observed the Fermi/LAT GRB 160625B (Dirirsa et al., GCN 19580) with the AMI Large Array at 15 GHz on 2016 Jun 28.06 (UT), 2.1 days post-burst, as part of the 4pisky program. We detect a radio source consistent with the VLA location (Alexander et al., GCN 19606) at 640+/-40 uJy. Monitoring of this source is underway. We thank the AMI staff for scheduling these observations. The AMI-GRB database is a log of all GRB follow up observations with the AMI, and is available at http://4pisky.org/ami-grb/.
GCN 19611 table
GRB_name GRB160625B
GCN_number 19611
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19611 SUBJECT: GRB 160625B: SAO RAS optical observations DATE: 16/06/28 14:00:13 GMT FROM: Moskvitin Alexander at SAO RAS A. Moskvitin (SAO RAS, Russia) report on behalf of the larger team. After fruitful multiband observations of the GRB 160625B optical counterpart by several telescopes including Mini-MegaTORTORA system located at SAO RAS (Karpov et al. GCNC #19603) we observed the GRB160625B field (Dirirsa et al. GCNC #19580) with the 1-meter telescope Zeiss-1000 of SAO RAS on June, 27.923 (1.976 days after the trigger). 7 x 300 sec. images in Rc band were obtained under good weather conditions. The OT is clearly visible in separate frames and in the stacked frame. It's position is perfectly consistent with the coordinates reported by Troja et al. (GCNC #19588) and Alexander et al. (GCNC #19606). During our observations the OT magnitude was R = 19.87 +/- 0.07. This estimation is based on the R2 magnitudes of nearby USNO-B1 stars, without any correction for the Galactic extinction in the GRB direction. The finding chart can be found at ftp://ftp.sao.ru/pub/grb/GRB160625B/GRB160625B_z1000.jpg
GCN 19612 table
GRB_name GRB160625B
GCN_number 19612
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19612 SUBJECT: GRB 160625B: Global MASTER-Net prompt optical emission detection DATE: 16/06/28 14:05:38 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs E. Gorbovskoy, V. Lipunov, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov, D.Kuvshinov, Lomonosov Moscow State University, Sternberg Astronomical Institute R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory O.Gres, K.Ivanov, S.Yazev, N.M.Budnev, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Senik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, A.Gabovich, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk Ricardo Podesta, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) MASTER-IAC robotic telescope (MASTER-Net: http://observ.pereplet.ru) was pointed to the GRB 160625B (Burns et al., GCN19581) 31 sec after GBM notice time and 57 sec after GBM trigger (131 sec before LAT Trigger, Dirirsa et al., GCN 19580) at 2016-06-25 22:41:13UT . Starting from this time we continiously observed Swift X-ray error box (Melandri et al., GCN 19585) by MASTER-IAC wide field camera with 5 sec unfiltered exposition. We have several thousands frames. The OT appears at 22 43 30 (+- 2.5 sec) UT and rised to maximum ~8 mag after ~5 sec at RATIR position (Troja et al., GCN 19588). The prompt optical emission strongly correlated with Konus Wind gamma ray light curve ( Svinkin et al., GCN 19604 ). MASTER-IAC robotic telescope started OT error box observation 43 sec after LAT notice time and 95 sec after trigger time at 2016-06-25 22:44:59 in two polarisations. The OT was about ~ 9.7 mag at this moment ( 0.2B + 0.8R with respect to USNOB1.0 stars) The delay with publication connected with installation new MASTER telescope at Argentina (http://master.sai.msu.ru/masternet/). The message may be cited.
GCN 19615 table
GRB_name GRB160625B
GCN_number 19615
Detection_method Optical
ra 308.5979°
decl 6.9189°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19615 SUBJECT: Pi of the Sky detection of an optical flash accompanying GRB 160625B DATE: 16/06/28 19:34:52 GMT FROM: Lech Wiktor Piotrowski at U Warsaw T. Batsch, A.J. Castro-Tirado, R. Cunniffe, H. Czyrkowski, A. Ćwiek, M. Ćwiok, R. Dąbrowski, M. Jelínek, G. Kasprowicz, A.Majcher, K. Małek, L. Mankiewicz, K. Nawrocki, Ł. Obara, R. Opiela, M. Siudek, M. Sokołowski, L. W. Piotrowski, R. Wawrzaszek, G. Wrochna, A Zadrożny, M. Zaremba, A.F. Żarnecki (Pi of the Sky Collaboration) Following GCN 19603 we present the reconstructed light curve of GRB 160625B. One of four Pi of the Sky North detectors located at INTA - El Arenosillo observatory in Mazagón near Huelva, Spain imaged the region of GRB 160625B (Swift-XRT error circle (Melandri, et al., GCN 19585), at a position RA, Dec = 20:34:23.50, +6:55:8.1) before, during and after the GRB with 10s exposures (the exposures were taken in white light, IR-cut and UV-cut filters only, to achieve deepest detection limit). Cameras of the Pi of the Sky North observatory were observing the position of the GRB160625B 48s after Fermi GBM trigger 488587220 time (Jun 25 22:40:16.28 UT) 140 seconds before the LAT 488587408 trigger (Jun 25 22:43:24.82 UT). We observed optical emission at the position given by Swift XRT recording a bright light curve starting -5.9 s before the LAT trigger. The first 10 s exposure shows initial magnitude of ~9.18 (unfiltered) brightening to ~8.04 on the second exposure, than becoming gradually dimmer. It is important to note that both cameras, 35 and 39, identified a new object on exposures starting just before the time of the trigger. Below we give the light curve of GRB 160625B separately for two cameras: For camera id = 35 t - t0 MagV ErrV -5.90351900 9.17858000 0.01979590 7.30034010 8.04185240 0.00692530 20.50411000 8.85256720 0.01464740 33.70891000 9.16411390 0.01958250 46.91391000 9.35221170 0.02310580 60.12562000 9.48356820 0.02605830 73.33060000 9.76273220 0.03348310 86.53484000 9.88869010 0.03764580 110.75906000 10.36167800 0.05831040 123.96549000 10.36315500 0.05835510 137.17366000 10.65792100 0.07717340 150.37855000 10.78365300 0.08672800 163.58296000 10.90103300 0.09643880 176.79191000 11.10503700 0.11532510 190.00141000 11.27645400 0.13539200 203.20498000 11.43088800 0.15646540 216.40969000 11.52125300 0.16944510 229.59719000 11.66219300 0.19535900 242.80196000 11.97388500 0.26215110 255.98556000 11.44272600 0.15893520 269.18835000 12.22780400 0.33061590 282.39288000 11.70644300 0.20138410 295.59737000 12.10355100 0.29637090 308.80171000 12.01954200 0.27279960 348.41412000 12.14943500 0.30407830 388.02095000 12.20940300 0.32526530 For camera id = 39 t-t0 MagV ErrV -0.21738000 8.08332450 0.00848860 15.13208000 8.39624730 0.01125160 30.48032000 9.30388780 0.02600590 45.83497000 9.38090950 0.02766380 61.69324000 9.60060770 0.03356240 77.04026000 9.76118030 0.03894990 92.38808000 10.00068600 0.04923380 107.71683000 10.23761200 0.05958340 123.06963000 10.43917000 0.07335490 138.42439000 10.63567700 0.08856020 153.77331000 10.78614800 0.10097800 169.12145000 10.99128200 0.12175100 184.46995000 11.23445500 0.15126550 199.82483000 11.04686000 0.12786780 215.17292000 11.27135000 0.15866670 232.56505000 11.47398300 0.19109480 247.89472000 11.99905600 0.31466480 263.75136000 11.78799000 0.25153010 279.09823000 12.08530200 0.33607390 294.44611000 11.95412600 0.30025650 325.14680000 12.14188100 0.35312590 432.59537000 12.18551500 0.36922680 Indicated errors are statistical only. Estimated systematic uncertainty of the image calibration is around 0.06-0.08 mag. T0 is the Fermi GBM trigger 488587408 time (Jun 25 22:43:24.82 UT) and t is the time of shutter oppening. Each image taken covers approximately 400 square degrees. The magnitudo limit was about 12.5 mag. Pi of the Sky observations are performed in wide visible band, with IR-cut and UV-cut filters only. We calibrate our observations to the reference stars from Tycho 2 using the transformation from Tycho to Pi of the Sky system given by: VPi = VT + 0.235313 - 0.292266*(BT - VT) Due to the proximity of the burst to the edge of our FoV, the transient was not detected automatically. However, this allowed us to record it with two cameras, with exposures slightly shifted in time. The light curve is available at: http://grb.fuw.edu.pl/results/gamma-ray-bursts/grb160625b/. More information will be published at http://grb.fuw.edu.pl and http://grb.fuw.edu.pl/results/gamma-ray-bursts/grb160625b/ [GCN OPS NOTE(04jul16): Per author's request, the GRB name in the 2nd paragraph was corrected, and RC was added to the author list.]
GCN 19616 table
GRB_name GRB160625B
GCN_number 19616
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19616 SUBJECT: GRB 160625B: SMARTS optical/IR afterglow observations DATE: 16/06/28 20:56:18 GMT FROM: Bethany Cobb at GWU B. E. Cobb (GWU) reports: Using the ANDICAM instrument on the 1.3m telescope at CTIO, we obtained optical/IR imaging of the error region of GRB 160625B (GCN 19580, Dirirsa et al.) with a mid-exposure time of about 32 hours post-burst (2016-06-27 06:51 UT). Total summed exposure times amounted to 36 minutes in I and 30 minutes in J. The afterglow of GRB 160625B (e.g. GCN 19585, Melandri et al.; GCN 19588, Troja et al.; GCN 19589, Oates et al.) is detected in our images. Preliminary comparison to USNO-B1.0 stars in I and 2MASS stars in J indicates the following afterglow magnitudes: mid-exposure time post-burst I mag J mag 1.338 days 18.9+/-0.2 18.6+/-0.1
GCN 19617 table
GRB_name GRB160625B
GCN_number 19617
Detection_method CALET
Circular_text TITLE: GCN CIRCULAR NUMBER: 19617 SUBJECT: GRB 160625B CALET Gamma-Ray Burst Monitor detection DATE: 16/06/29 08:09:50 GMT FROM: Takanori Sakamoto at AGU S. Nakahira (JAXA), A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU), S. Ricciarini (U of Florence) P. S. Marrocchesi (U of Siena) and the CALET collaboration: The long-duration GRB 160625B (Burns et al., GCN Circ. 19581; Dirirsa et al. GCN Circ. 19586; INTEGRAL-ACS #7495) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 22:40:15.49 on 25 June 2016. The burst signal was seen by all CGBM instruments. The light curve of the SGM shows a precursor emission starting at T+0.5 sec, peaking at T+1 sec and ending at T+2 sec. Then, the bright main burst episode follows starting from T+183 sec and ending at T+233 sec with overlapping multiple pulses. The T90 duration measured by the SGM data for the main bright episode is 20.0 +- 0.4 sec (40-1000 keV). The T90 duration of the precursor emission measured by the SGM data is 0.8 +- 0.1 sec (40-1000 keV). The light curve is available at http://cgbm.calet.jp/cgbm_trigger/flight/1150929566/ Furthermore, the main pulse was also detected by Imaging Calorimeter (IMC; plastic scintillating fibers) and Charge Detector (CHD; plastic scintillators), which are subsystems of the CALET main instrument Calorimeter (CAL). The incident angles for this burst was 61 degrees and 67 degrees from the boresight of CAL at the trigger time and at the main peak, respectively. The CAL gamma-ray analysis (>1 GeV) is in progress. The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
GCN 19619 table
GRB_name GRB160625B
GCN_number 19619
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19619 SUBJECT: GRB 160625B: TSHAO optical observations DATE: 16/06/29 15:18:38 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Kusakin (Fesenkov Astrophysical Institute), P. Minaev (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 160625B (Dirirsa et al., GCN 19580; Burns et al. GCN 19581) with Zeiss-1000 (East) 1-m telescopes of Tien Shan Astronomical Observatory. We obtained several images in R filter starting on June 27 (UT) 20:15:57. We detect optical afterglow of GRB 160625B (Troja et al., GCN 19588; Oates et al., GCN 19589). Preliminary photometry of a combined image is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2016-06-27 20:15:57 1.92994 R 54*60 19.56 0.06 22.0 Photometry is based on nearby USNO-B1.0 stars reported in GCN 19605 (Mazaeva et. al).
GCN 19620 table
GRB_name GRB160625B
GCN_number 19620
Detection_method correction
Circular_text TITLE: GCN CIRCULAR NUMBER: 19620 SUBJECT: GRB 160625B: TSHAO optical observations, correction GCN 19619 DATE: 16/06/29 15:45:03 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: Corrected text of the GCN 19619 (Mazaeva et al.) should be as follows. E. Mazaeva (IKI), A. Kusakin (Fesenkov Astrophysical Institute), P. Minaev (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 160625B (Dirirsa et al., GCN 19580; Burns et al. GCN 19581) with Zeiss-1000 (East) 1-m telescopes of Tien Shan Astronomical Observatory. We obtained several images in R filter starting on June 28 (UT) 18:12:30. We detect optical afterglow of GRB 160625B (Troja et al., GCN 19588; Oates et al., GCN 19589). Preliminary photometry of a combined image is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2016-06-28 18:12:30 2.86135 R 63*120 20.32 0.06 22.7 Photometry is based on nearby USNO-B1.0 stars reported in GCN 19605 (Mazaeva et. al). I thank D. A. Kann who noticed the apparent error.
GCN 19640 table
GRB_name GRB160625B
GCN_number 19640
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19640 SUBJECT: GRB 160625B: LCOGT FTN observations DATE: 16/07/01 16:43:58 GMT FROM: Cristiano Guidorzi at Ferrara U,Italy C. Guidorzi (U. Ferrara), S. Kobayashi (LJMU), C.G. Mundell (U. Bath), A. Gomboc (U. Nova Gorica), on behalf of a large collaboration report: We observed Fermi GRB 160625B (Dirirsa et al. GCN 19580) with the 2-m LCOGT Faulkes Telescope North in Hawaii on July 01 from 11:12 UT to 12:46 UT with the SDSS-r filter for a total exposure of 1500 s. We clearly detect the optical afterglow (Troja et al. GCN 19588; Oates et al. GCN 19589; Kuroda et al. GCN 19599; Xu et al. GCN 19600; D'Elia et al. GCN 19601; Karpov et al. GCN 19603; Mazaeva et al. GCN 19605; Moskvitin et al. GCN 19611; Gorbovskoy et al. GCN 19612; Batsch et al. GCN 19615; Cobb et al. GCN 19616) with a magnitude of r=21.15 +- 0.15 mag at a mid epoch of 5.5 days post burst, as calibrated against nearby USNOB1 stars.
GCN 19642 table
GRB_name GRB160625B
GCN_number 19642
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19642 SUBJECT: GRB 160625B: SAO RAS monitoring DATE: 16/07/02 13:55:29 GMT FROM: Vladimir Sokolov at SAO RAS A. F. Valeev, A. S. Moskvitin, G. M. Beskin, V. V. Vlasyuk, V. V. Sokolov (SAO RAS, Russia) report on behalf of the larger GRB follow-up team. We observed the GRB160625B field (Dirirsa et al. GCNC #19580) with two optical telescopes of SAO RAS: the 6-m BTA + Scorpio (B, V, Rc, Ic bands), and the 1-meter telescope Zeiss-1000 + CCD photometer (Rc band) at the June 29/30 night. We clearly detected an OT (Troja et al. ,GCNC #19588; Karpov et al GCNC #19603; Alexander et al. GCNC #19606) in our stacked frames. Preliminary Rc band results are shown in the following table. These estimations are based on the R2 magnitudes of the same nearby USNO-B1 stars as in our previous GCNC #19611. Mid_date, UT T-T0,d exp,s R_mag err Telescope ================================================================= June, 29.827 3.880 3 x 200 20.53 +/- 0.07 BTA June, 29.983 4.036 8 x 300 20.56 +/- 0.20 Zeiss-1000
GCN 19651 table
GRB_name GRB160625B
GCN_number 19651
Detection_method Optical
ra 308.5809°
decl 6.9099°
Circular_text TITLE: GCN CIRCULAR NUMBER: 19651 SUBJECT: GRB 160625B: RTT150 optical observations DATE: 16/07/04 13:42:20 GMT FROM: Rodion Burenin at IKI, Moscow I. Bikmaev, E. Irtuganov, N. Sakhibullin (KFU/AST), R. Burenin, M. Pavlinsky, R. Sunyaev (IKI), I. Khamitov, H. Kirbiyik (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.) report: We observed field of Fermi GRB 160625B (Dirirsa et al. GCN 19580) at the position of optical afterglow (Troja et al. ,GCN 19588) with Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National Observatory, Turkey) using the TFOSC instrument. We obtained series of Rc exposures in June 30 / July 01(6 frames x 600 sec, UT = 00:21 - 01:30 ), in July 01 / 02 (4 frames x 900 sec, UT = 00:36 - 01:42), in July 02 / 03 (6 frames x 900 sec, UT = 23:49 - 01:29), and in July 03 / 04, 2016, (14 frames x 600 sec, UT = 22:50 - 01:39). The optical transient (Troja et al. GCN 19588; Oates et al. GCN 19589; Kuroda et al. GCN 19599; Xu et al. GCN 19600; D'Elia et al. GCN 19601; Watson at al. GCN 19602; Karpov et al. GCN 19603; Mazaeva et al. GCN 19605, 19620; Moskvitin et al. GCN 19611; Gorbovskoy et al. GCN 19612; Batsch et al. GCN 19615; Cobb et al. GCN 19616; Guidorzi et al. GCN 19640; Valeev et al. GCN 19642) is clearly detected in each images. Using USNO-B1 0969-0608410 star at RA,DEC = 308.580912 +06.909881 (J2000) with R = 16.73 mag as a reference we estimated the Rc-magnitudes of the afterglow in stacked images: T-T0, Mag., Mag.err days 5.09 20.69 +- 0.03 6.10 20.96 +- 0.04 7.08 21.04 +- 0.03 8.06 21.24 +- 0.04 RTT-150 data show that OT is fading at approximately the same power law rate as it was observed earlier.
GCN 19680 table
GRB_name GRB160625B
GCN_number 19680
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19680 SUBJECT: GRB 160625B: TSHAO optical observations DATE: 16/07/11 12:56:47 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Kusakin (Fesenkov Astrophysical Institute), P. Minaev (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Volnova (IKI), A. Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration: We observed the field of GRB 160625B (Dirirsa et al., GCN 19580; Burns et al. GCN 19581) with Zeiss-1000 (East) 1-m telescopes of Tien Shan Astronomical Observatory. We obtained several images in R filter on July 8 and 10. We detect optical afterglow of GRB 160625B (Troja et al., GCN 19588; Oates et al., GCN 19589). Preliminary photometry of a combined image is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2016-07-08 19:01:43 12.9172 R 30*300 21.60 0.15 22.7 2016-07-10 18:19:18 14.8713 R 29*300 21.64 0.08 23.3 Photometry is based on nearby USNO-B1.0 stars reported in GCN 19605 (Mazaeva et. al).
GCN 19683 table
GRB_name GRB160625B
GCN_number 19683
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 19683 SUBJECT: GRB 160625B: Global MASTER-Crimea prompt optical emission detection (fwd) DATE: 16/07/12 19:03:59 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov, P.Balanutsa, A.Kuznetsov, D.Kuvshinov, Lomonosov Moscow State University, Sternberg Astronomical Institute R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory O.Gres, K.Ivanov, S.Yazev, N.M.Budnev, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Senik Kislovodsk Solar Station of the Pulkovo Observatory V.Yurkov, Yu.Sergienko, A.Gabovich, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk Ricardo Podesta, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA) Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE) MASTER-Crimea robotic telescope (testing camera 20 cm) pointing to LAT error box (Dirirsa et al., GCN 19580) 12 sec after LAT notice time and 66 sec after trigger time at 2016-06-25 22:44:30 UT in unfiltered mode. The OT was about 9.55 +-0.01 mag at this moment ( 0.2B + 0.8R with respect to USNOB1.0 stars) The automatic photometry and astrometry are: +id- time coord2000 mag 179841451 22:44:30.055 20h 34m 23.49s , +06d 55m 07s.6 9.55 179890027 22:44:30.055 20h 34m 23.52s , +06d 55m 07s.9 10.11 179845079 22:45:00.899 20h 34m 23.50s , +06d 55m 07s.8 10.03 179878574 22:45:37.806 20h 34m 23.52s , +06d 55m 08s.0 10.54 179909653 22:46:25.105 20h 34m 23.53s , +06d 55m 07s.8 11.46 179883969 22:46:25.105 20h 34m 23.52s , +06d 55m 07s.8 11.04 179895778 22:47:20.57 20h 34m 23.52s , +06d 55m 07s.9 11.52 179901960 22:48:26.68 20h 34m 23.52s , +06d 55m 08s.0 11.91 The delay with internet problems last time . The message may be cited.