GRB170705A

This page lists all entries on GRB170705A in GRBweb

Summary Fermi GBM IPN Swift GCN 21289 GCN 21290 GCN 21291 GCN 21292 GCN 21293 GCN 21294 GCN 21295 GCN 21296 GCN 21297 GCN 21298 GCN 21299 GCN 21300 GCN 21301 GCN 21302 GCN 21303 GCN 21320 GCN 21327

Summary table
Variable Value Source
GRB_name_Fermi GRB170705115
T0 2:45:47 UTC GCN_circulars,Swift Det
ra 191.7040° Swift
decl 18.3073° Swift
pos_error 5.82e-05° Swift
T90 22.781 s Fermi_GBM
T90_error 1.377 s Fermi_GBM
T90_start 2:45:51.036 UTC Fermi_GBM
fluence 1.34e-05 erg/cm² Fermi_GBM
fluence_error 6.31e-08 erg/cm² Fermi_GBM
redshift 2.0100
T100 217.3 s
GBM_located False
mjd 57939.11512731481 GCN_circulars,Swift Det
Fermi GBM table
GRB_name_Fermi GRB170705115
trigger_name bn170705115
ra 191.7042°
decl 18.3075°
pos_error 2.70e+00°
datum 2017-07-05
t_trigger 2:45:51.032 UTC
T90 22.781 s
T90_error 1.377 s
T90_start 2:45:51.036 UTC
fluence 1.34e-05 erg/cm²
fluence_error 6.31e-08 erg/cm²
flux_1024 2.25e+01 erg/cm²/s
flux_1024_error 5.46e-01 erg/cm²/s
flux_1024_time 9.41e+00 erg/cm²/s
flux_64 2.67e+01 erg/cm²/s
flux_64_error 2.44e+00 erg/cm²/s
IPN table
GRB_name GRB170705A
ra 191.7042°
decl 18.3000°
pos_error 5.00e-02°
redshift 2.0100
Swift table
GRB_name GRB170705A
t_trigger 2:45:47 UTC
ra 191.7040°
decl 18.3073°
pos_error 5.82e-05°
T90 217.3 s
fluence 9.50e-06 erg/cm²
redshift 2.0100
GCN 21289 table
GRB_name GRB170705A
GCN_number 21289
Detection_method Swift Det
t_trigger 2:45:47 UTC
ra 191.7050°
decl 18.2930°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21289 SUBJECT: GRB 170705A: Swift detection of a burst with an optical counterpart DATE: 17/07/05 03:08:15 GMT FROM: David Palmer at LANL R. L. C. Starling (U Leicester), A. Cholden-Brown (PSU), J. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. Stamatikos (OSU/NASA/GSFC) report on behalf of the Swift Team: At 02:45:47 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 170705A (trigger=760064). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 191.705, +18.293 which is RA(J2000) = 12h 46m 49s Dec(J2000) = +18d 17' 35" with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a multi-peaked structure with a duration of about 40 sec. The peak count rate was ~17000 counts/sec (15-350 keV), at ~13 sec after the trigger. The XRT began observing the field at 02:46:59.3 UT, 72.3 seconds after the BAT trigger. Using promptly downlinked data we find a bright, uncatalogued X-ray source located at RA, Dec 191.70472, 18.30811 which is equivalent to: RA(J2000) = 12h 46m 49.13s Dec(J2000) = +18d 18' 29.2" with an uncertainty of 3.8 arcseconds (radius, 90% containment). This location is 54 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 http://www.swift.ac.uk/sper. A power-law fit to a spectrum formed from promptly downlinked event data gives a column density in excess of the Galactic value (1.46 x 10^20 cm^-2, Willingale et al. 2013), with an excess column of 4.6 (+3.03/-2.52) x 10^21 cm^-2 (90% confidence). The initial flux in the 2.5 s image was 1.57e-09 erg cm^-2 s^-1 (0.2-10 keV). UVOT took a finding chart exposure of 150 seconds with the White filter starting 81 seconds after the BAT trigger. There is a candidate afterglow in the rapidly available 2.7'x2.7' sub-image at RA(J2000) = 12:46:48.97 = 191.70406 DEC(J2000) = +18:18:26.2 = 18.30727 with a 90%-confidence error radius of about 0.76 arc sec. This position is 3.7 arc sec. from the center of the XRT error circle. The estimated magnitude is 18.65 with a 1-sigma error of about 0.15. No correction has been made for the expected extinction corresponding to E(B-V) of 0.02. Burst Advocate for this burst is R. L. C. Starling (rlcs1 AT star.le.ac.uk). 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/too.html.)
GCN 21290 table
GRB_name GRB170705A
GCN_number 21290
Detection_method Swift-XRT Det
ra 191.7043°
decl 18.3074°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21290 SUBJECT: GRB 170705A: Enhanced Swift-XRT position DATE: 17/07/05 05:26:47 GMT FROM: Phil Evans at U of Leicester M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team. Using 569 s of XRT Photon Counting mode data and 1 UVOT images for GRB 170705A, we find an astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 191.70427, +18.30741 which is equivalent to: RA (J2000): 12h 46m 49.02s Dec (J2000): +18d 18' 26.7" with an uncertainty of 1.8 arcsec (radius, 90% confidence). This position may be improved as more data are received. The latest position can be viewed at http://www.swift.ac.uk/xrt_positions. Position enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans et al. (2009, MNRAS, 397, 1177). This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN 21291 table
GRB_name GRB170705A
GCN_number 21291
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 21291 SUBJECT: GRB 170705A: MASTER-OAFA early OT observations DATE: 17/07/05 09:26:46 GMT FROM: Vladimir Lipunov at Moscow State U/Krylov Obs V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, D.Kuvshinov, A.V.Krylov, I.Gorbunov, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D. Vlasenko Lomonosov Moscow State University, Sternberg Astronomical Institut of MSU R.Podesta, C.Lopez, F. Podesta Observatorio Astronomico Felix Aguilar (OAFA), National University of San Juan, Argentina H. Levato, C. Saffe Instituto de Ciencias Astronomicas,de la Tierra y del Espacio (ICATE), San Juan, Argentina K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk, O. Ershova Irkutsk State University V.Yurkov, Yu.Sergienko Blagoveschensk Educational State University, Blagoveschensk A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov Kislovodsk Solar Station of the Pulkovo Observatory D.Buckley, S. Potter, A.Kniazev, M.Kotze South African Astronomical Observatory R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres The Instituto de Astrofisica de Canarias MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in OAFA was pointed to the GRB170705A (Starling et al.,GCN #21289) 24 sec after notice time and 38 sec after trigger time at 2017-07-05 02:46:27 UT at high zenit distance. On our first (10s exposure) unfiltered exposition we haven't found optical transient within SWIFT error-box (ra=191.704 dec=18.2928 r=0.05) brighter than 15.0. We marginally found OT at Swift UVOT position (Starling et al.,GCN #21289) on coaded image ID=79921 with m ~ 17.0. ID DATE UT Exp Type Limit Note 79817 2017-07-05 02:46:27 10 Alert (SWIFT) 15.0 no 79921 2017-07-05 02:46:27 190 SumAlert (SWIFT) 16.9 79817+79825+79820+79818 79818 2017-07-05 02:47:20 20 Alert (SWIFT) 15.8 yes 79819 2017-07-05 02:48:24 30 Alert (SWIFT) 15.9 no 79820 2017-07-05 02:49:38 50 Alert (SWIFT) 16.2 yes 79822 2017-07-05 02:51:13 60 Alert (SWIFT) 16.3 no 79824 2017-07-05 02:52:57 90 Alert (SWIFT) 16.5 no 79825 2017-07-05 02:55:11 110 Alert (SWIFT) 16.4 yes 79826 2017-07-05 02:57:46 140 Alert (SWIFT) 16.4 no 79827 2017-07-05 03:00:48 180 Alert (SWIFT) 16.7 no 79829 2017-07-05 03:04:32 180 Alert (SWIFT) 16.3 no 79830 2017-07-05 03:08:12 180 Alert (SWIFT) 16.0 no The unfiltered magnitude is about ~17 m . The big differences with UVOT magnitude may be connected with high GRB redshift because our CCD is more red. The observations made on zenit distance = 79 degrees, galaxy latitude b = 81 degree. The moon (86 % bright part) is 66 degrees above the horizon. The distance between moon and object is 56 The sun altitude is -63.1 degree. The object can be observed till 2017-07-05 03:46:20 . The message may be cited.
GCN 21292 table
GRB_name GRB170705A
GCN_number 21292
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 21292 SUBJECT: GRB 170705A: Swift-XRT refined Analysis DATE: 17/07/05 10:34:21 GMT FROM: Phil Evans at U of Leicester S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU) and R.L.C. Starling report on behalf of the Swift-XRT team: We have analysed 8.4 ks of XRT data for GRB 170705A (Starling et al. GCN Circ. 21289), from 62 s to 22.1 ks after the BAT trigger. The data comprise 424 s in Windowed Timing (WT) mode (the first 8 s were taken while Swift was slewing) with the remainder in Photon Counting (PC) mode. The enhanced XRT position for this burst was given by Goad et al. (GCN Circ. 21290). The late-time light curve (from T0+4.6 ks) can be modelled with a power-law decay with a decay index of alpha=0.83 (+/-0.09). A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.53 (+/-0.03). The best-fitting absorption column is 8.4 (+1.1, -1.0) x 10^20 cm^-2, in excess of the Galactic value of 1.5 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.87 (+0.09, -0.08) and a best-fitting absorption column of 1.29 (+0.26, -0.24) x 10^21 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.6 x 10^-11 (4.5 x 10^-11) erg cm^-2 count^-1. A summary of the PC-mode spectrum is thus: Total column: 1.29 (+0.26, -0.24) x 10^21 cm^-2 Galactic foreground: 1.5 x 10^20 cm^-2 Excess significance: 7.7 sigma Photon index: 1.87 (+0.09, -0.08) If the light curve continues to decay with a power-law decay index of 0.83, the count rate at T+24 hours will be 0.11 count s^-1, corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.0 x 10^-12 (5.0 x 10^-12) erg cm^-2 s^-1. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00760064. This circular is an official product of the Swift-XRT team.
GCN 21293 table
GRB_name GRB170705A
GCN_number 21293
Detection_method Swift-UVOT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 21293 SUBJECT: GRB 170705A: RATIR Optical and NIR Observations DATE: 17/07/05 14:58:02 GMT FROM: Nat Butler at Az State U 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 (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report: We observed the field of GRB 170705A (Starling, et al., GCN 21289) 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 2017/07 5.17 to 2017/07 5.26 UTC (1.34 to 3.41 hours after the BAT trigger), obtaining a total of 1.42 hours exposure in the r and i bands and 0.59 hours exposure in the Z, Y, J, and H bands. We detect the optical transient found by Swift and observed MASTER-OAFA (Lipunov, et al., GCN 21291). In comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following detections: r = 18.60 +/- 0.01 i = 18.30 +/- 0.01 Z = 18.03 +/- 0.01 Y = 17.79 +/- 0.01 J = 17.79 +/- 0.01 H = 17.56 +/- 0.01 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. The source fades as in time as t^(-0.4) during our observation. We note that the Swift-UVOT detection makes this GRB unlikely to be at very high redshift. Our photo-z calculations, using RATIR data alone, suggest z<4. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
GCN 21294 table
GRB_name GRB170705A
GCN_number 21294
Detection_method Swift-UVOT Det
ra 191.7040°
decl 18.3073°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21294 SUBJECT: GRB 170705A: Swift/UVOT Detection DATE: 17/07/05 15:08:53 GMT FROM: Sam Emery at MSSL-UCL S.W.K. Emery (UCL-MSSL) and R. L. C. Starling (U. Leicester) report on behalf of the Swift/UVOT team: The Swift/UVOT began settled observations of the field of GRB 170705A 82 s after the BAT trigger (Starling et al., GCN Circ. 21289). We detect a fading source consistent with the XRT position (Goad et al., GCN Circ. 21290) and the MASTER (Lipunov et al., GCN Circ. 21291) and RATIR (Butler et al., GCN Circ. 21293) detections in the initial UVOT exposures. The preliminary UVOT position is: RA (J2000) = 12:46:48.97 = 191.70404 (deg.) Dec (J2000) = +18:18:26.4 = 18.30733 (deg.) with an estimated uncertainty of 0.45 arc sec. (radius, 90% confidence). Preliminary 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC) exposure and subsequent exposures are: Filter T_start(s) T_stop(s) Exp(s) Mag white_FC 82 231 147 18.55 +/- 0.06 white 573 1020 186 19.23 +/- 0.11 u 294 543 246 19.43 +/- 0.19 v 623 1070 58 >18.3 b 549 741 39 18.92 +/- 0.26 uvw1 672 692 19 >18.1 uvm2 4617 12950 996 >20.7 uvw2 5644 11420 1137 >21.0 The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.02 in the direction of the burst (Schlegel et al. 1998).
GCN 21295 table
GRB_name GRB170705A
GCN_number 21295
Detection_method MITSuME
Circular_text TITLE: GCN CIRCULAR NUMBER: 21295 SUBJECT: GRB 170705A: MITSuME Akeno Optical Observation DATE: 17/07/05 15:27:51 GMT FROM: Taketoshi Yoshii at Tokyo Tech S. Harita, Y. Saito, R. Itoh, Y. Tachibana, T. Yoshii, K. Morita, T. Ozawa, H. Mamiya, K. Shiraishi, Y. Yatsu, and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration: We searched for the optical counterpart of GRB 170705A (R. L. C. Starling et al., GCN Circular #21289) with the optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50cm telescope of Akeno Observatory, Yamanashi, Japan. The observation started on 2017-07-05 11:21:20.84 UT. We did not find any new point source within XRT circle in all three bands. We obtained following limits for the magnitudes. T0+[hour] MID-UT T-EXP[sec] g' Rc Ic ------------------------------------------------------------------------------------------------------- ~8.59 12:29:51 1320 >18.5 >17.9 >17.8 ------------------------------------------------------------------------------------------------------- T0+ : Elapsed time after the burst T-EXP: Total Exposure time We used GSC2.3 catalog for flux calibration.
GCN 21296 table
GRB_name GRB170705A
GCN_number 21296
Detection_method Swift-BAT Det
ra 191.7080°
decl 18.2980°
Circular_text TITLE: GCN CIRCULAR NUMBER: 21296 SUBJECT: GRB 170705A: Swift-BAT refined analysis DATE: 17/07/05 16:14:33 GMT FROM: Amy Lien at GSFC H. A. Krimm (NSF/USRA), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU), R. L. C. Starling (U Leicester), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team): Using the data set from T-239 to T+963 sec from the recent telemetry downlink, we report further analysis of BAT GRB 170705A (trigger #760064) (Starling et al., GCN Circ. 21289). The BAT ground-calculated position is RA, Dec = 191.708, 18.298 deg which is RA(J2000) = 12h 46m 50.0s Dec(J2000) = +18d 17' 51.3" with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment). The partial coding was 83%. The mask-weighted light curve shows a multi-peaked structure that starts at ~ T0 and ends at ~ T+300 s. The main emission occurs at ~ T0 to ~ T+40 s, with the major peak at ~ T+14 s. T90 (15-350 keV) is 217.3 +- 18.0 sec (estimated error including systematics). The time-averaged spectrum from T+0.44 to T+304.86 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.65 +- 0.05. The fluence in the 15-150 keV band is 9.5 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+13.41 sec in the 15-150 keV band is 13.9 +- 0.4 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/760064/BA/ [GCN OPS NOTE(06jul17): Per author's request, the last paragaph was added.]
GCN 21297 table
GRB_name GRB170705A
GCN_number 21297
Detection_method Fermi GBM Det
t_trigger 2:45:51.030 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 21297 SUBJECT: GRB 170705A: Fermi GBM observation DATE: 17/07/05 18:03:09 GMT FROM: Elisabetta Bissaldi at U.Innsbruk/IAPP E. Bissaldi (Politecnico & INFN Bari) and C. Meegan (UAH) report on behalf of the Fermi GBM Team: "At 02:45:51.03 UT on 5 July 2017, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 170705A (trigger 520915556 / 170705115), which was also detected by the Swift/BAT (Starling et al. 2017, GCN 21289). The GBM on-ground location is consistent with the Swift position. The angle from the Fermi LAT boresight at the GBM trigger time is 118 degrees. The GBM light curve shows two peaks with a duration (T90) of about 22 s (50-300 keV). The time-averaged spectrum from T0-2 s to T0+20 s is adequately fit by a Band function with Epeak = 100 +/- 10 keV, alpha = -0.88 +/- 0.07, and beta = -2.38 +/- 0.09. The event fluence (10-1000 keV) in this time interval is (1.37 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from T0+9.4 s in the 10-1000 keV band is 22.5 +/- 0.5 ph/s/cm^2. The spectral analysis results presented above are preliminary; final results will be published in the GBM GRB Catalog."
GCN 21298 table
GRB_name GRB170705A
GCN_number 21298
Detection_method Other
redshift 2.0100
Circular_text TITLE: GCN CIRCULAR NUMBER: 21298 SUBJECT: GRB 170705A: Redshift from 10.4m GTC/OSIRIS DATE: 17/07/05 23:48:25 GMT FROM: Antonio de Ugarte Postigo at IAA-CSIC A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D.A. Kann (IAA-CSIC), L. Izzo (IAA-CSIC), C.C. Thoene (IAA-CSIC) report on behalf of the HETH group: We observed the afterglow of GRB 170705A (Starling et al. GCN 21289, Lipunov et al. GCN 21291, Butler et al. GCN 21293, Emery et al. GCN 21294) with OSIRIS at the 10.4m GTC telescope. The observation consisted of 3x900s using grism R1000B, covering the range between 3700 and 7880 AA at a mean epoch of July 5.9350 2017 UT (19.68 hr after the burst). The acquisition shows the afterglow at a magnitude of r(AB) = 20.20 +/- 0.10 mag, as compared to SDSS field stars. The spectrum shows continuum across all the spectral range, although the signal to noise ratio of the bluest part is low because of the bright sky due of the nearby almost full Moon. We detect weak spectral absorption features due to CIV, AlII, AlIII, FeII and FeII* at a common redshift of 2.010, which we identify as the redshift of the GRB.
GCN 21299 table
GRB_name GRB170705A
GCN_number 21299
Detection_method Konus-Wind Det
t_trigger 2:45:56.188 UTC
redshift 2.0100
Circular_text TITLE: GCN CIRCULAR NUMBER: 21299 SUBJECT: Konus-Wind observation of GRB 170705A DATE: 17/07/06 11:16:24 GMT FROM: Dmitry Svinkin 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 GRB 170705A (Swift-BAT observation: Starling et al., GCN Circ. 21289; Fermi-GBM observation: Bissaldi and Meegan, GCN Circ. 21297) triggered Konus-Wind at T0=9956.188 s UT (02:45:56.188). The burst light curve shows a bright, multipeaked pulse, which starts at ~T0-6 s and has a total duration of ~25 s, followed by a weaker emission seen up to ~T0+300 s. The emission in the main episode is seen up to ~1 MeV. The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB170705_T09956/ As observed by Konus-Wind, the burst had a fluence of 1.76(-0.19,+0.20)x10^-5 erg/cm2, and a 64-ms peak flux, measured from T0+2.384 s, of 4.21(-0.94,+0.96)x10^-6 erg/cm2/s (both in the 20 keV - 10 MeV energy range). The time-averaged spectrum of the main episode (measured from T0 to T0+24.832 s) is best fit in the 20 keV - 2 MeV range by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) with alpha = -1.31(-0.17,+0.20) and Ep = 155(-22,+31) keV (chi2 = 53/62 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -2.7 (chi2 = 59/61 dof). The spectrum near the maximum count rate (measured from T0+0.256 to T0+8.448 s) is best fit in the 20 keV - 2 MeV range by a power law with exponential cutoff model: with alpha = -1.16(-0.15,+0.16) and Ep = 166(-18,+23) keV (chi2 = 69/61 dof). Fitting by a GRB (Band) model yields the same alpha and Ep, and an upper limit on the high energy photon index: beta < -3 (chi2 = 69/60 dof). Assuming the redshift z=2.010 (de Ugarte Postigo et al., GCN Circ. 21298) 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 ~1.8x10^53 erg, the peak luminosity L_iso is ~1.3x10^53 erg/s, and the rest-frame peak energy of the time-integrated spectrum, Ep,i, is ~466 keV. All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN 21300 table
GRB_name GRB170705A
GCN_number 21300
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 21300 SUBJECT: GRB 170705A: ISON/Terskol optical observations DATE: 17/07/06 13:28:01 GMT FROM: Alexei Pozanenko at IKI, Moscow E. Mazaeva (IKI), A. Pozanenko (IKI), V. Agletdinov (KIAM), A. Volnova (IKI), A. Mokhnatkin (KIAM), I. Molotov (KIAM) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 170705A (Starling et al. GCN 21289) which is also detected by GBM/Fermi and Konus-Wind (Bissaldi et al., GCN 21297; Svinkini et al., GCN 21299) with K-800 (0.8m) telescope of ISON/Terskol observatory starting on July, 05 (UT) 18:30:54. We obtained several unfiltered images of 20 s exposure. The optical afterglow of GRB 170705A (Starling et al. GCN 21289, Lipunov et al. GCN 21291, Butler et al. GCN 21293, Emery et al. GCN 21294; Ugarte Postigo et al. GCN 21298) is clearly visible in a combined image. Preliminary photometry of the afterglow is following Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) 2017-07-05 18:30:54 0.70649 CR 358*20 19.84 0.08 22.2 Photometry is based on nearby SDSS DR9 stars SDSS id R_Lupton J124702.82+181926.7 17.63 J124700.96+181851.9 19.15 J124653.35+182058.9 17.08 J124641.28+182043.7 16.61 J124646.57+181522.1 17.45 J124645.71+181510.4 17.18 J124650.58+182306.3 18.18 J124624.60+181820.0 16.34 J124647.75+181330.6 16.05 J124644.99+181414.3 18.79
GCN 21301 table
GRB_name GRB170705A
GCN_number 21301
Detection_method Insight-HXMT Det
Circular_text TITLE: GCN CIRCULAR NUMBER: 21301 SUBJECT: GRB 170705A: Insight-HXMT observation DATE: 17/07/06 18:10:53 GMT FROM: Shaolin Xiong at IHEP F. J. Lu, C. K. Li, S. L. Xiong, C. Z. Liu, X. F. Li, Z. W. Li, X. B. Li, J. Y. Liao, Y. Huang, Y. H. Wang, Z. Chang, X. F. Lu, J. L. Zhao, A. M. Zhang, Y. F. Zhang, C. L. Zou (IHEP), Y. J. Jin, Z. Zhang (THU), Y. P. Chen, M. Gao (IHEP), T. P. Li (IHEP/THU), G. Li, M. S. Li, H. W. Liu, L. M. Song, W. H. Tao, H. Y. Wang, X. Y. Wen, M. Wu, H. Xu, Y. P. Xu, C. M. Zhang, F. Zhang, J. Zhang, T. Zhang, S. N. Zhang (IHEP), report on behalf of the Insight-HXMT team: During the commissioning phase, at 2017-07-05T02:45:59.00 (T0), Insight-HXMT detected GRB 170705A (trigger ID: HEB170705115) in a routine search of the data, which was also observed by the Swift/BAT (Starling et al. 2017, GCN 21289), Fermi/GBM (Bissaldi et al. 2017, GCN 20297) and Konus-Wind (Svinkin et al. 2017, GCN 21299). The Insight-HXMT light curve consists of single pulse with a duration (T90) of 7.0 s measured from T0-1.30 s. The 1-second peak rate, measured from T0+1 s, is 928.3 cnts/sec. The total counts from this burst is 3458 counts. All measurements above are made with the CsI detectors in the energy range of about 80-840 keV (record energy) in the regular mode. Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed on the inside of the telescope. URL_LC: http://www.hxmt.org/images/GRB/HEB170705115_lc.jpg The time-averaged spectrum from T0-2 s to T0+8 s is adequately fit by a Power Law model with spectral index = -2.16 +/- 0.10. The energy fluence is (1.42 +/- 0.30)E-05 erg/cm^2 in 200 - 5000 keV in this time interval. The analysis results presented above are preliminary; final results will be published elsewhere. Insight-HXMT is the first Chinese space X-ray telescope, which was funded jointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information about it could be found at: http://www.hxmt.org/index.php/enhome .
GCN 21302 table
GRB_name GRB170705A
GCN_number 21302
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 21302 SUBJECT: GRB 170705A: KAIT Optical Observations DATE: 17/07/06 18:23:52 GMT FROM: Max Genecov at UC Berkeley Max Genecov, WeiKang Zheng, and Alex Filippenko (UC Berkeley) report on behalf of the KAIT GRB team: The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at Lick Observatory, responded to Swift GRB 170705A (Starling, et al.,GCN 21289), starting 1.66 hours after the burst and again 1.08 days after the burst. Observations were performed in the clear (roughly R) filter, and the exposure time was 60 s per image. The optical afterglow of GRB 170705A (Starling, et al.,GCN 21289; Lipunov et al., GCN 21291; Butler et al. GCN 21293, Emery et al. GCN 21294, Ugarte Postigo et al. GCN 21298, Pozenenko et al. GCN 21300) was clearly detected in every single image from the first night and in an image co-added from thirteen frames in the second night. Preliminary photometry of the afterglow calibrated to several nearby SDSS stars gives 18.1 +/- 0.2 mag at mean time 1.66 hours and 20.3 +/- 0.3 mag at mean time 1.08 days.
GCN 21303 table
GRB_name GRB170705A
GCN_number 21303
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 21303 SUBJECT: GRB 170705A: Further RATIR Optical and NIR Observations and Steepening of Fading DATE: 17/07/06 18:37:15 GMT FROM: Alan M. Watson at Instituto de Astronomia UNAM Alan M. Watson (UNAM), 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 (UVI), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jesús González (UNAM), Carlos Román-Zúñiga (UNAM), Harvey Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report: We observed the field of GRB 170705A (Starling et al., GCN Circ. 21289) 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 2017/07 6.17 to 2017/07 6.26 UTC (25.33 to 27.52 hours after the BAT trigger), obtaining a total of 1.02 hours exposure in the r and i bands and 0.37 hours exposure in the Z, Y, J, and H bands. For a source within the Swift-XRT error circle, in comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following detections: r = 20.62 +/- 0.05 i = 20.35 +/- 0.05 Z = 19.68 +/- 0.07 Y = 19.72 +/- 0.09 J = 19.46 +/- 0.10 H = 19.61 +/- 0.16 These magnitudes are in the AB system and are not corrected for Galactic extinction in the direction of the GRB. The source has faded on average by 1.90 +/- 0.17 magnitudes compared to our previous observations (Butler et al., GCN Circ. 21293). This corresponds to a temporal index of -0.72 +/- 0.03, which is steeper than the index of -0.4 we saw during our previous observations. We thank the staff of the Observatorio Astronómico Nacional in San Pedro Mártir.
GCN 21320 table
GRB_name GRB170705A
GCN_number 21320
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 21320 SUBJECT: GRB 170705A: TShAO optical observations DATE: 17/07/11 17:39:03 GMT FROM: Alexei Pozanenko at IKI, Moscow A. Volnova (IKI), E. Mazaeva (IKI), A. Pozanenko (IKI), A. Kusakin (Fesenkov Astrophysical Institute), I. Reva (Fesenkov Astrophysical Institute) report on behalf of larger GRB follow-up collaboration: We observed the field of the Swift GRB 170705A (Starling et al. GCN 21289) which is also detected by GBM/Fermi and Konus-Wind (Bissaldi et al., GCN 21297; Svinkin et al., GCN 21299) with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory on July 6-8. We took several images in R-filter. The optical afterglow of GRB 170705A (Starling et al. GCN 21289, Lipunov et al. GCN 21291, Butler et al. GCN 21293, Emery et al. GCN 21294; Ugarte Postigo et al. GCN 21298) is visible in a combined image on July 6, and upper limit only for July 7-8. Preliminary photometry of the afterglow is following. Date UT start t-T0 Filter Exp. OT Err. UL (mid, days) (s) (3 sigma) 2017-07-06 16:28:29 1.61411 R 38*180 20.67 0.24 21.1 2017-07-07 17:30:55 2.63106 R 13*180 n/d n/d 20.6 2017-07-07 17:30:55 3.10501 R 34*180 n/d n/d 21.1 Photometry is based on nearby SDSS DR9 stars listed in GCN 21300.
GCN 21327 table
GRB_name GRB170705A
GCN_number 21327
Detection_method AstroSat CZTI
t_trigger 2:46:00 UTC
T90 14.9 s
Circular_text TITLE: GCN CIRCULAR NUMBER: 21327 SUBJECT: GRB 170705A: AstroSat CZTI detection DATE: 17/07/12 13:18:15 GMT FROM: Vidushi Sharma at IUCAA V. Sharma (IUCAA), V. Bhalerao (IIT-B), D. Bhattacharya (IUCAA), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the Astrosat CZTI collaboration: Analysis of Astrosat CZTI data showed the detection of a long-duration GRB 170705A, which was also detected by Swift/BAT (Starling et al., GCN 21289), Fermi/GBM (Bissaldi et al., GCN 21297), Konus-Wind (Svinkin et al., GCN 21299) and Insight-HXMT (Lu et al., GCN 21301). The source was clearly detected in the 40-200 keV energy range. The light curve shows multiple peaks of emission with the strongest peak at 02:46:00 UT, ~13 s after the Swift Trigger. The measured peak count rate is 635.9 cts/s above the background in combined data of four quadrants, with a total of 3123 cts. The local mean background count rate was 374.1 cts/s. Using cumulative rates, we measure a T90 of 14.9 s. It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range. CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.