Gamma-ray Burst 160709A

(All information courtesy of the instrument teams.)

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Results of Observations

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 Jul 16 19:49:27 UT
NOTICE_TYPE:     Fermi-GBM Flight Position
RECORD_NUM:      45
TRIGGER_NUM:     489786547
GRB_RA:          234.067d {+15h 36m 16s} (J2000),
                 234.315d {+15h 37m 16s} (current),
                 233.316d {+15h 33m 16s} (1950)
GRB_DEC:         -26.333d {-26d 19' 59"} (J2000),
                 -26.387d {-26d 23' 13"} (current),
                 -26.168d {-26d 10' 05"} (1950)
GRB_ERROR:       4.90 [deg radius, statistical plus systematic]
GRB_INTEN:       584 [cnts/sec]
DATA_SIGNIF:     28.40 [sigma]
INTEG_TIME:      1.024 [sec]
GRB_DATE:        17578 TJD;   191 DOY;   16/07/09
GRB_TIME:        71343.51 SOD {19:49:03.51} UT
GRB_PHI:         295.00 [deg]
GRB_THETA:        50.00 [deg]
DATA_TIME_SCALE: 1.0240 [sec]
HARD_RATIO:      0.45
LOC_ALGORITHM:   3 (version number of)
MOST_LIKELY:      95%  GRB
2nd_MOST_LIKELY:   4%  Generic Transient
DETECTORS:       0,0,0, 1,1,0, 0,0,0, 0,0,0, 0,0,
SUN_POSTN:       109.52d {+07h 18m 04s}  +22.22d {+22d 13' 28"}
SUN_DIST:        129.89 [deg]   Sun_angle= -8.3 [hr] (East of Sun)
MOON_POSTN:      174.53d {+11h 38m 07s}   +3.32d {+03d 18' 55"}
MOON_DIST:        64.89 [deg]
MOON_ILLUM:      29 [%]
GAL_COORDS:      342.99, 23.44 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      238.02, -6.80 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn160709826/quicklook/glg_lc_medres34_bn160709826.gif
COMMENTS:        Fermi-GBM Flight-calculated Coordinates.  
COMMENTS:        This trigger occurred at longitude,latitude = 79.97,19.38 [deg].  
COMMENTS:        The LC_URL file will not be created until ~15 min after the trigger.

GCN NOTICE

TITLE:           GCN/FERMI NOTICE
NOTICE_DATE:     Sat 09 Jul 16 19:49:41 UT
NOTICE_TYPE:     Fermi-GBM Ground Position
RECORD_NUM:      57
TRIGGER_NUM:     489786547
GRB_RA:          228.250d {+15h 13m 00s} (J2000),
                 228.501d {+15h 14m 00s} (current),
                 227.492d {+15h 09m 58s} (1950)
GRB_DEC:         -29.800d {-29d 48' 00"} (J2000),
                 -29.861d {-29d 51' 39"} (current),
                 -29.613d {-29d 36' 47"} (1950)
GRB_ERROR:       4.32 [deg radius, statistical only]
DATA_SIGNIF:     32.90 [sigma]
DATA_INTERVAL:   1.024 [sec]
GRB_DATE:        17578 TJD;   191 DOY;   16/07/09
GRB_TIME:        71343.51 SOD {19:49:03.51} UT
GRB_PHI:         301.00 [deg]
GRB_THETA:        54.00 [deg]
E_RANGE:         44.032 - 279.965 [keV]
LOC_ALGORITHM:   4153 (Gnd S/W Version number)
SUN_POSTN:       109.52d {+07h 18m 04s}  +22.22d {+22d 13' 28"}
SUN_DIST:        125.26 [deg]   Sun_angle= -7.9 [hr] (East of Sun)
MOON_POSTN:      174.53d {+11h 38m 08s}   +3.31d {+03d 18' 52"}
MOON_DIST:        61.28 [deg]
MOON_ILLUM:      29 [%]
GAL_COORDS:      336.24, 23.76 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      233.87,-11.45 [deg] ecliptic lon,lat of the burst (or transient)
LC_URL:          http://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2016/bn160709826/quicklook/glg_lc_medres34_bn160709826.gif
POS_MAP_URL:     http://gcn.gsfc.nasa.gov/notices_f/gbm_gnd_loc_map_489786547.fits
COMMENTS:        Fermi-GBM Ground-calculated Coordinates.  
COMMENTS:        In the LAT Field-of-view.  
COMMENTS:        Bright hard burst in the GBM.  
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 #19674
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 160709A. Automated analysis of the XRT data will be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00057
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 Circular #19675
S. Guiriec (NASA GSFC/UMD/CRESST), G. Vianello (Stanford) & J. Racusin (NASA GSFC) report on behalf of the Fermi-LAT team:
At 19:49:03.50 on July, 09, 2016 Fermi-LAT detected high-energy emission from GRB 160709A, which was also detected by Fermi-GBM (trigger 489786546 / 160709826). The best LAT on-ground location is found to be
RA, Dec = 236.110, -28.500 (J2000)
with an error radius of 0.18 deg (90 % containment, statistical error only). This was 48 deg from the LAT boresight at the time of the trigger. The data from the Fermi-LAT show a significant increase in the event rate that is spatially and temporally correlated with the trigger with high significance. More than 30 photons above 100 MeV are observed within 100 seconds, with the highest-energy photons being 1 GeV events observed 2 seconds after the GBM trigger and consistent with the GBM brightest emission episode.
A Swift ToO has been requested for this burst.
The Fermi-LAT point of contact for this burst is Sylvain Guiriec ( sylvain.guiriec@nasa.gov).
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 Circular #19676
P. Jenke (UAH) reports on behalf of the Fermi GBM Team:
"At 19:49:03.50 UT on 09 July 2016, the Fermi Gamma-Ray Burst Monitor triggered and located GRB 160709A (trigger 489786547 / 160709826), which was also detected by the LAT (Guiriec et al. 2016, GCN 19675). The GBM on-ground location is consistent with the LAT position.
The angle from the Fermi LAT boresight at the GBM trigger time is 48 degrees.
The GBM light curve consists of two peaks with a duration (T90) of about 5.6 s (50-300 keV) beginning 64 ms before the trigger time. The time-averaged spectrum from T0-0.26 s to T0+0.83 s is best fit by a power law function with an exponential high-energy cutoff. The power law index is -0.43 +/- 0.04 and the cutoff energy, parameterized as Epeak, is 2211 +/- 131 keV.
The event fluence (10-1000 keV) in this time interval is (3.33 +/- 0.09)E-06 erg/cm^2. The 1-sec peak photon flux measured starting from T0-0.06 s in the 10-1000 keV band is 6.5 +/- 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 #19677
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline, on behalf of the Konus-Wind team, report:
The short/hard GRB 160709A (Fermi-LAT detection: Guiriec, et al., GCN Circ. 19675; Fermi-GBM detection: Jenke, GCN Circ. 19676) triggered Konus-Wind at T0=3D71345.896 s UT (19:49:05.896).
The light curve shows a short, hard pulse with a total duration of ~0.4 s. The emission is seen up to ~8 MeV.
As observed by Konus-Wind, the burst had a fluence of (1.5 =B1 0.3)x10^-5 erg/cm2 and a 16-ms peak energy flux, measured from T0, of (6.3 =B1 0.9)x10^-5 erg/cm2 (both in the 20 keV - 10 MeV energy range).
The spectrum of the burst (measured from T0 to T0+0.256 s) is best fit in the 20 keV - 10 MeV range by a cutoff power-law (CPL) function with the following model parameters: the photon index alpha =3D -0.51(-0.17,+0.19), and the peak energy Ep =3D 2554(-509,+664) keV, chi2 =3D 40.1/50 dof. Fitting this spectrum with the GRB (Band) function yields the same alpha and Ep with only an upper limit on beta of -2.1, chi2 =3D 39.8/49 dof.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB160709_T71345/
All the quoted errors are estimated at the 90% confidence level. All the presented results are preliminary.
GCN Circular #19678
V. Lipunov, E. Gorbovskoy, N.Tyurina, P.Balanutsa, V.Kornilov, A.Kuznetsov, D.Kuvshinov, Lomonosov Moscow State University, Sternberg Astronomical Institute
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
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 II robotic telescope (MASTER-Net: http://observ.pereplet.ru) located in SAAO was pointed to the GRB160709.83 66 sec after notice time and 105 sec after trigger time at 2016-07-09 19:50:49 UT. On our first (20s exposure) set we no found OT within FERMI error-box (ra=15 12 59 dec=-29 48 00 r=4.32) brighter then 18.8.
But this field do not included FERMI LAT error box (Guiriec et al., GCN 19675).
MASTER-SAAO robotic telescope located in SAAO was continue inspection of the GRB160709A and 1727 sec after FERMI GBM notice time (Jenke, GCN 19676) and before 9709 sec FERMI LAT notice time and 1750 sec after trigger time at 2016-07-09 20:18:14 UT observed FERI LAT error box. On our 120s exposure set we not found OT within FERMI LAT error-box (Guiriec et al., GCN 19675) brighter then 19.6.
The message may be cited.
GCN Circular #19679
T.G.R. Roegiers (PSU), S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai (INAF-IASFPA), L.M. McCauley (PSU), J.A. Kennea (PSU), B. Mingo (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 160709A (Guiriec et al. GCN Circ. 19675) in a series of observations tiled on the sky. The total exposure time is 3.3 ks, distributed over 7 tiles; the maximum exposure at a single sky location was 1.4 ks. The data were collected between T0+20.7 ks and T0+39.1 ks, and are entirely in Photon Counting (PC) mode.
No uncatalogued X-ray sources have been detected. The 3-sigma upper limit in the field (not including the regions where the tiles overlap) ranges from ~0.01 to ~0.06 ct s^-1, corresponding to a 0.3-10 keV observed flux of 4.3e-13 to 2.2e-12 erg cm^-2 s^-1 (assuming a typical GRB spectrum).
Two previously-catalogued X-ray sources have been detected, however their status as catalogued objects makes them unlikely to be the afterglow.
The results of the XRT-team automatic analysis of the tiled XRT observations, including a position-specific upper limit calculator, are available at http://www.swift.ac.uk/xrt_products/TILED_GRB00057.
This circular is an official product of the Swift-XRT team.
GCN Circular #19681
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL), J. P. Norris (BSU), M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
At 19:49:03.464 UT on 2016-07-09, BAT detected a count rate increase and a sub-threshold signal in the image. Due to the sub-threshold nature, this event did not trigger a normal burst event-by-event response. Using the data set from T-2 to T+8 sec from the recent telemetry downlink, the ground analysis found an 8.8 sigma detection in a 10-s image in 15-350 keV. As discussed below, this is likely the same burst, GRB160709A, that was detected by Fermi/GBM (Jenke et al. GCN Circ. 19676), Fermi/LAT (Guiriec et al. GCN Circ. 19675), and Konus-Wind (Frederiks et al. GCN Circ. 19677).
The BAT ground-calculated position is RA, Dec = 235.996, -28.188 deg which is
```
  RA(J2000)  =  15h 43m 59.1s
  Dec(J2000) = -28d 11' 18.2"
```
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 19%.
The mask-weighted light curve shows a multi-peaked structure that starts at ~T0 and peaks at ~T+0.8 s. The main pulses end at ~T+1 s, but there are some weak emissions that continue beyond the event data range. T90 (15-350 keV) estimated from the raw light curve is 4.8 +- 1.6 sec (estimated error including systematics).
The time-averaged spectrum from T+0.0 to T+4.8 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.11 +- 0.28. The fluence in the 15-150 keV band is 4.5 +- 0.7 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+0.30 sec in the 15-150 keV band is 2.7 +- 0.4 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
Using a 16-ms binned light curve, the lag of the initial pulse (~T0 to ~T+1 s) for the 100-350 keV to 25-50 keV bands is 3 (+/-5) ms (with 1-sigma error). Using a 4-ms binned light curve, the lag of the initial pulse for the same energy bands is 6 (+/-5) ms. These values are consistent with those from a short GRB.
The detection time of this burst is only ~0.04 s from the Fermi/GBM trigger time of GRB160709A (Jenke et al., GCN Circ. 19676). Also, the burst structure is very similar to the one seen in the GBM. We thus believe the BAT detection is highly likely to be GRB160709A.
However, we note that the BAT location is ~0.33 degrees from the LAT location and outside of the reported LAT error circle of 0.18 deg (statistical error only; Guiriec et al. GCN Circ. 19675). The large dispersion in the position measurements may be explained by the unknown systematic uncertainty in the LAT position. Nonetheless, we cannot rule out the possibility that these are independent events.
The BAT location for this burst is covered by the XRT tiling search. No XRT or UVOT afterglows are found within the BAT error circle.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/703769/BA/
GCN Circular #19682
V. Lipunov, E. Gorbovskoy, N.Tyurina, P.Balanutsa, V.Kornilov, A.Kuznetsov, D.Kuvshinov, Lomonosov Moscow State University, Sternberg Astronomical Institute
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
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
R.Podesta, C.Lopez and F.Podest Observatorio Astronomico Felix Aguilar (OAFA)
H.Levato and C.Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
MASTER-SAAO robotic telescope (2x4 square degrees twin telescope, http://observ.pereplet.ru) was pointing to the Swift-BAT error box (Sakamoto et al., GCN 19681) during Fermi-GBM alert inspection 1727 sec after FERMI GBM notice time (Jenke, GCN 19676) and before 9709 sec FERMI LAT notice time and 1750 sec after trigger time at 2016-07-09 20:18:14 UT. On our 180s exposure set we not found OT within Swift-BAT (Sakamoto et al., GCN 19681) brighter then 19.6.
The inspection and references images are available at http://master.sai.msu.ru/static/GRB160709A_MASTER_SAAO.png .
The message may be cited.
GCN Circular #19701
Y. Asaoka (Waseda U), A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama, Y. Yamada (AGU), K. Yamaoka (Nagoya U), S. Nakahira (JAXA), I. Takahashi (IPMU), 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 short-duration GRB 160709A (Guiriec, et al., GCN circ. 19675; Jenke, et al., GCN circ. 19676; Frederiks, et al. GCN circ. 19677) triggered the CALET Gamma-ray Burst Monitor (CGBM) at 19:49:04.67 on 9 July 2016. No real time CGBM GCN notice was distributed about this trigger because the real time communication from the ISS was off (loss of signal) between 19:42 and 20:04. The burst signal was seen by all CGBM instruments.
The light curve of the SGM shows a single starting at T-0.2 sec, peaking at T0-0.1 sec and ending at T+0.2 sec. The T90 duration measured by the SGM data is 0.38 +- 0.04 sec (600-3000 keV).
The light curve is available at
http://cgbm.calet.jp/cgbm_trigger/flight/1152128868/
The CALET data used in this analysis are provided by the Waseda CALET Operation Center located at the Waseda University.
GCN Circular #19740
V. Bhalerao (IUCAA), V. Kumar (IUCAA), D. Bhattacharya (IUCAA), A. R. Rao (TIFR), S. Vadawale (PRL) report on behalf of the Astrosat CZTI collaboration:
Analysis of Astrosat data showed the CZTI detection of a short GRB 160709A (Fermi-LAT detection: Guiriec, et al., GCN Circ. 19675).
The GRB occured at an angle of 124 degrees away from the CZTI pointing direction. The source was clearly detected in the 40-200 keV energy range. The light curve shows a single peak at 19:49:04.00 UT, 0.5 seconds after Fermi Trigger at 19:49:03.50 and a peak count rate of 1035.0 counts/sec above the background (four quadrants summed together), with a total of 3878.0 counts. The local mean background count rate was 314.0 counts/sec. Using cumulative rates, we measure a T90 of 0.45 sec, consistent with the Konus-Wind measurement of 0.4s (Frederiks et al., GCN Circ. 19677) and CALET (Asaoka et al., GCN Circ. 19701) but inconsistent with Swift-BAT (Sakamoto et al., GCN Circ. 19681) and Fermi (Jenke et al., GCN Circ. 19676).
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.

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