Gamma-ray Burst 170710B

(All information courtesy of the instrument teams.)

Previous IAU Circulars

• none

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 10 Jul 17 08:10:32 UT
  NOTICE_TYPE:     Fermi-GBM Flight Position
  RECORD_NUM:      47
  TRIGGER_NUM:     521367012
  GRB_RA:           37.500d {+02h 30m 00s} (J2000),
                    37.777d {+02h 31m 06s} (current),
                    36.713d {+02h 26m 51s} (1950)
  GRB_DEC:         +41.133d {+41d 07' 60"} (J2000),
                   +41.211d {+41d 12' 38"} (current),
                   +40.911d {+40d 54' 41"} (1950)
  GRB_ERROR:       10.95 [deg radius, statistical plus systematic]
  GRB_INTEN:       135 [cnts/sec]
  DATA_SIGNIF:     8.00 [sigma]
  INTEG_TIME:      2.048 [sec]
  GRB_DATE:        17944 TJD;   191 DOY;   17/07/10
  GRB_TIME:        29408.00 SOD {08:10:08.00} UT
  GRB_PHI:         295.00 [deg]
  GRB_THETA:        50.00 [deg]
  DATA_TIME_SCALE: 2.0480 [sec]
  HARD_RATIO:      0.32
  LOC_ALGORITHM:   3 (version number of)
  MOST_LIKELY:      64%  GRB
  2nd_MOST_LIKELY:  28%  Distant Particles
  DETECTORS:       0,0,0, 1,1,0, 0,0,0, 0,0,0, 0,0,
  SUN_POSTN:       109.79d {+07h 19m 11s}  +22.19d {+22d 11' 22"}
  SUN_DIST:         62.36 [deg]   Sun_angle= 4.8 [hr] (West of Sun)
  MOON_POSTN:      303.18d {+20h 12m 43s}  -17.80d {-17d 48' 11"}
  MOON_DIST:       105.00 [deg]
  MOON_ILLUM:      99 [%]
  GAL_COORDS:      142.21,-18.02 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:       48.79, 24.91 [deg] ecliptic lon,lat of the burst (or transient)
  LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170710340/quicklook/glg_lc_medres34_bn170710340.gif
  COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
  COMMENTS:        This trigger occurred at longitude,latitude = 247.20,25.50 [deg].  
  COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.  
  

• GCN NOTICE
  

  TITLE:           GCN/FERMI NOTICE
  NOTICE_DATE:     Mon 10 Jul 17 08:10:45 UT
  NOTICE_TYPE:     Fermi-GBM Ground Position
  RECORD_NUM:      56
  TRIGGER_NUM:     521367012
  GRB_RA:           41.610d {+02h 46m 26s} (J2000),
                    41.906d {+02h 47m 38s} (current),
                    40.767d {+02h 43m 04s} (1950)
  GRB_DEC:         +47.890d {+47d 53' 24"} (J2000),
                   +47.963d {+47d 57' 46"} (current),
                   +47.680d {+47d 40' 50"} (1950)
  GRB_ERROR:       7.49 [deg radius, statistical only]
  DATA_SIGNIF:     12.00 [sigma]
  DATA_INTERVAL:   4.096 [sec]
  GRB_DATE:        17944 TJD;   191 DOY;   17/07/10
  GRB_TIME:        29408.00 SOD {08:10:08.00} UT
  GRB_PHI:         301.00 [deg]
  GRB_THETA:        44.00 [deg]
  E_RANGE:         44.032 - 279.965 [keV]
  LOC_ALGORITHM:   4153 (Gnd S/W Version number)
  SUN_POSTN:       109.79d {+07h 19m 11s}  +22.19d {+22d 11' 22"}
  SUN_DIST:         59.08 [deg]   Sun_angle= 4.5 [hr] (West of Sun)
  MOON_POSTN:      303.18d {+20h 12m 43s}  -17.80d {-17d 48' 10"}
  MOON_DIST:       108.89 [deg]
  MOON_ILLUM:      99 [%]
  GAL_COORDS:      142.09,-10.66 [deg] galactic lon,lat of the burst (or transient)
  ECL_COORDS:       54.53, 30.23 [deg] ecliptic lon,lat of the burst (or transient)
  LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2017/bn170710340/quicklook/glg_lc_medres34_bn170710340.gif
  POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_521367012.fits
  COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
  COMMENTS:        This Notice was ground-generated -- not flight-generated.  
  COMMENTS:        The LC_URL file will not be created/available until ~15 min after the trigger.  
  COMMENTS:        The POS_MAP_URL file will not be created/available until ~1.5 min after the notice.  
  

• GCN Circular #21316
  D. M. Palmer (LANL) and A. Y. Lien (GSFC/UMBC) report on behalf of the Swift Team:
  At 08:10:06.251 UT on 2017-07-10, the Swift Burst Alert Telescope (BAT) detected a GRB during a pre-planned slew to a scheduled target. Ground analysis using data from T-25 to T+79 s finds the source at a location of RA, Dec = 43.122, 42.679 deg which is

    RA(J2000)  =  02h 52m 29.3s
    Dec(J2000) = +42d 40' 43.6"
  

  with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
  The mask-weighted light curve shows a single FRED-like pulse that starts and peaks at ~T0, and ends at ~T+60 s. T90 (15-350 keV) is 54.4 +- 1.6 sec (estimated error including systematics).
  The time-averaged spectrum from T+0.0 to T+59.2 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.38 +- 0.08. The fluence in the 15-150 keV band is 2.4 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+5.10 sec in the 15-150 keV band is 1.2 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
  This GRB also triggered Fermi/GBM (GBM trigger# 521367012).
  A Swift Target of Opportunity observation has been requested.
  The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/00086619001/BA/.
• GCN Circular #21317
  P. A. Evans (U. Leicester) reports on behalf of the Swift team:
  Swift has initiated a ToO observation of the Fermi/GBM GRB 170710B. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/ToO_GRBs/00020777
  Any uncatalogued X-ray sources detected in this analysis will be reported on this website and via GCN COUNTERPART notices. These are not necessarily related to the Fermi/GBM event. 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 Circular #21318
  K.L. Page (U. Leicester), A. D'Ai (INAF-IASFPA), A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU), A. Cholden-Brown (PSU), B. Mingo (U. Leicester), A.P. Beardmore (U. Leicester), A.A. Breeveld (MSSL/UCL), S.B. Cenko (GSFC) and P.A. Evans (U. Leicester) report on behalf of the Swift team:
  Swift has performed follow-up observations of the BAT and Fermi/GBM-detected burst GRB 170710B (Palmer & Lien, GCN Circ. 21316), collecting 4.0 ks of Photon Counting (PC) mode data between T0+85.2 ks and T0+92.7 ks.
  One uncatalogued X-ray source has been detected consistent with being within 296 arcsec of the BAT position; it is below the RASS limit and shows no definitive signs of fading. It is 4.8" from SDSS J025227.08+423819.4, which is a possible quasar, therefore more data are needed to confirm whether the XRT source is the GRB afterglow. Further observations are planned. Details of this source are given below:
  Source 1:

    RA (J2000.0):  43.1110  =  02:52:26.65
    Dec (J2000.0): +42.6391  =  +42:38:20.7
    Error: 3.3 arcsec (radius, 90% conf. [Enhanced position])
    Count-rate: (6.4 [+1.6, -1.4])e-3 ct s^-1
    Distance: 146 arcsec from BAT position.  
    Flux: (2.51 [+0.61, -0.56])e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)
  

  The UVOT started observing this source 85.2 ks after the burst. The catalogued source just on the edge of the XRT region is detected, but no new source is found to an upper limit in the UVW2 filter of 21.3 mag in 3924s of exposure.
  Two uncatalogued X-ray sources were also detected too far from the GRB position to be likely afterglow candidates.
  The results of the XRT-team automatic analysis of the XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/ToO_GRBs/00020777.
  This circular is an official product of the Swift2 team.
• GCN Circular #21319
  R. Hamburg (UAH), C. Meegan (UAH), and E. Bissaldi (Politecnico & INFN Bari): report on behalf of the Fermi GBM Team:
  "At 08:10:08.00 UT on 10 July 2017, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 170710B (trigger 521367012 / 170710340) which was also detected by the Swift/BAT (D. Palmer et al. 2017, GCN 21316) The GBM on-ground location is consistent with the Swift position.
  The angle from the Fermi LAT boresight at the GBM trigger time is 49 degrees.
  The GBM light curve consists of one main peak with a duration (T90) of about 42 s (50-300 keV). The time-averaged spectrum from T0-4 s to T0+28 s is adequately fit by a power law function with an exponential high-energy cutoff. The power law index is -1.2 +/- 0.1 and the cutoff energy, parameterized as Epeak, is 293 +/- 61 keV. A Band function fits the spectrum equally well with Epeak= 149 +/- 49 keV, alpha = -0.9 +/- 0.2 and beta = -1.9 +/- 0.2.
  The event fluence (10-1000 keV) in this time interval is (6.0 +/- 0.4)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0+0.5 s in the 10-1000 keV band is 2.7 +/- 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 Circular #21354
  K.L. Page and P.A. Evans (U. Leicester) report on behalf of the Swift team:
  Swift performed a further observation of the field of the BAT and Fermi/GBM-detected burst GRB 170710B (Palmer & Lien, GCN Circ. 21316; Hamburg, Meegan & Bissaldi, GCN Circ. 21319) on 2017 July 15. The XRT-detected "Source 1", as given in Page et al. (GCN Circ. 21318), shows no sign of fading, with a count rate of (5.6 +1.9/-1.5)x10^-3 count s^-1 compared to (6.4 +/- 1.5)x10^-3 count s^-1 from the first observation on July 11. This is therefore not the GRB afterglow.
  This circular is an official product of the Swift-XRT team.
• GCN Circular #21461
  K. P. Mooley (Hintze Fellow, Oxford), T. D. Staley, R. P. Fender (Oxford), G. E. Anderson (Curtin), T. Cantwell (Manchester), D. Titterington, S. H. Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods, P. Scott (Cambridge), K. Grainge, A. Scaife (Manchester)
  The AMI Large Array triggered on the Swift alert for GRB 170710B (Palmer et al., GCN 21316) as part of the 4pisky program, and subsequent follow up observations were obtained up to 10 days post-burst. Our observations at 15 GHz on 2016 Jul 12.3, Jul 13.26, Jul 15.29 and Jul 19.23 (UT) do not reveal any radio source at the BAT location (Palmer et al., GCN 21316), with 3sigma upper limits of 153 uJy, 93 uJy, 93 uJy and 222 uJy respectively.
  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/.