Gamma-ray Burst 170714A

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:40:49 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     762535,   Seg_Num: 0
GRB_RA:           34.321d {+02h 17m 17s} (J2000),
                  34.547d {+02h 18m 11s} (current),
                  33.675d {+02h 14m 42s} (1950)
GRB_DEC:          +1.987d {+01d 59' 14"} (J2000),
                  +2.068d {+02d 04' 03"} (current),
                  +1.756d {+01d 45' 23"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=4304 [image_cnts]
TRIGGER_DUR:     320.000 [sec]   (=5.3 [min])
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        17948 TJD;   195 DOY;   17/07/14
GRB_TIME:        44732.63 SOD {12:25:32.63} UT
GRB_PHI:         112.46 [deg]
GRB_THETA:        24.09 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    8.63 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  -1  +0  +0 -17  +0 
SUN_POSTN:       114.05d {+07h 36m 12s}  +21.60d {+21d 35' 47"}
SUN_DIST:         79.48 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.39d {+23h 41m 33s}   -4.85d {-04d 50' 58"}
MOON_DIST:        39.73 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.72,-54.29 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       32.74,-11.09 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This Notice was delayed by more than 60 sec past the end of the trigger integration interval;  
COMMENTS:        probably due to it occurring during a Malindi downlink session.  
COMMENTS:        This is an image trigger.  (The RATE_SIGNIF & BKG_{INTEN, TIME, DUR} are undefined.)  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 258.28,19.75 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:41:20 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     762535,   Seg_Num: 0
GRB_RA:           34.3498d {+02h 17m 23.95s} (J2000),
                  34.5764d {+02h 18m 18.33s} (current),
                  33.7042d {+02h 14m 49.00s} (1950)
GRB_DEC:          +1.9901d {+01d 59' 24.3"} (J2000),
                  +2.0706d {+02d 04' 14.0"} (current),
                  +1.7594d {+01d 45' 33.7"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       2.46e-09 [erg/cm2/sec]
GRB_SIGNIF:      9.11 [sigma]
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45125.31 SOD {12:32:05.31} UT,   392.7 [sec] since BAT Trigger Time
TAM[0-3]:        327.68 237.20 261.74 243.55
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       114.05d {+07h 36m 12s}  +21.60d {+21d 35' 47"}
SUN_DIST:         79.45 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.39d {+23h 41m 34s}   -4.85d {-04d 50' 53"}
MOON_DIST:        39.76 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.76,-54.27 [deg] galactic lon,lat of the burst
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        The XRT position is 1.76 arcmin from the BAT position.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:41:30 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     762535,   Seg_Num: 0
GRB_RA:           34.3498d {+02h 17m 23.9s} (J2000),
                  34.5764d {+02h 18m 18.3s} (current),
                  33.7042d {+02h 14m 49.0s} (1950)
GRB_DEC:          +1.9901d {+01d 59' 24.3"} (J2000),
                  +2.0706d {+02d 04' 14.0"} (current),
                  +1.7594d {+01d 45' 33.7"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       83 [cnts]
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45125.31 SOD {12:32:05.31} UT,   392.7 [sec] since BAT Trigger Time
CENTROID_X:      296.03,  raw= 296  [pixels]
CENTROID_Y:      295.73,  raw= 296  [pixels]
ROLL:            68.38 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -6.27
GRB_POS_XRT_Z:   -24.42
IMAGE_URL:       sw00762535000msxps_rw.img
SUN_POSTN:       114.05d {+07h 36m 12s}  +21.60d {+21d 35' 47"}
SUN_DIST:         79.45 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.39d {+23h 41m 34s}   -4.85d {-04d 50' 51"}
MOON_DIST:        39.75 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.76,-54.27 [deg] galactic lon,lat of the burst
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:41:33 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     762535,   Seg_Num: 0
GRB_RA:           34.3498d {+02h 17m 23.9s} (J2000),
                  34.5764d {+02h 18m 18.3s} (current),
                  33.7042d {+02h 14m 49.0s} (1950)
GRB_DEC:          +1.9901d {+01d 59' 24.3"} (J2000),
                  +2.0706d {+02d 04' 14.0"} (current),
                  +1.7594d {+01d 45' 33.7"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       83 [cnts]
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45125.31 SOD {12:32:05.31} UT,   392.7 [sec] since BAT Trigger Time
CENTROID_X:      296.03,  raw= 296  [pixels]
CENTROID_Y:      295.73,  raw= 296  [pixels]
ROLL:            68.38 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   -6.27
GRB_POS_XRT_Z:   -24.42
IMAGE_URL:       sw00762535000msxps_rw.img
SUN_POSTN:       114.05d {+07h 36m 12s}  +21.60d {+21d 35' 47"}
SUN_DIST:         79.45 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.39d {+23h 41m 34s}   -4.85d {-04d 50' 51"}
MOON_DIST:        39.75 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.76,-54.27 [deg] galactic lon,lat of the burst
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:41:56 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     762535,   Seg_Num: 0
GRB_RA:           34.321d {+02h 17m 17s} (J2000),
                  34.547d {+02h 18m 11s} (current),
                  33.675d {+02h 14m 42s} (1950)
GRB_DEC:          +1.987d {+01d 59' 14"} (J2000),
                  +2.068d {+02d 04' 03"} (current),
                  +1.756d {+01d 45' 23"} (1950)
GRB_DATE:        17948 TJD;   195 DOY;   17/07/14
GRB_TIME:        44732.63 SOD {12:25:32.63} UT
TRIGGER_INDEX:   20000
GRB_PHI:         112.46 [deg]
GRB_THETA:        24.09 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     320.000 [sec]   (=5.3 [min])
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    8.63 [sigma]
LC_URL:          sw00762535000msb.lc
SUN_POSTN:       114.05d {+07h 36m 12s}  +21.60d {+21d 35' 47"}
SUN_DIST:         79.48 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.40d {+23h 41m 35s}   -4.85d {-04d 50' 47"}
MOON_DIST:        39.72 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.72,-54.29 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:       32.74,-11.09 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Lightcurve.  
COMMENTS:           
COMMENTS:        The next comments were copied from the BAT_POS Notice:  
COMMENTS:        This is an image trigger.  
COMMENTS:        A point_source was found.  
COMMENTS:        This does not match any source in the on-board catalog.  
COMMENTS:        This does not match any source in the ground catalog.  
COMMENTS:        This is a GRB.  
COMMENTS:        This trigger occurred at longitude,latitude = 258.28,19.75 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:43:12 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     762535,   Seg_Num: 0
POINT_RA:         34.345d {+02h 17m 23s} (J2000)
POINT_DEC:        +1.989d {+01d 59' 20"} (J2000)
POINT_ROLL:      68.381d
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45602.44 SOD {12:40:02.44} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.946
N_STARS:         27
X_OFFSET:        271 [pixels]
Y_OFFSET:        302 [pixels]
X_MAX:           1710 [pixels]
Y_MAX:           1741 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw00762535000msufc0869.fits
SUN_POSTN:       114.05d {+07h 36m 13s}  +21.60d {+21d 35' 46"}
SUN_DIST:         79.46 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.41d {+23h 41m 38s}   -4.84d {-04d 50' 34"}
MOON_DIST:        39.73 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.75,-54.27 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:43:29 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     762535,   Seg_Num: 0
POINT_RA:         34.345d {+02h 17m 23s} (J2000)
POINT_DEC:        +1.989d {+01d 59' 20"} (J2000)
POINT_ROLL:      68.381d
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45602.44 SOD {12:40:02.44} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          7, U
BKG_MEAN:        0.946
N_STARS:         27
X_OFFSET:        271 [pixels]
Y_OFFSET:        302 [pixels]
X_MAX:           1710 [pixels]
Y_MAX:           1741 [pixels]
DET_THRESH:      8
PHOTO_THRESH:    4
SL_URL:          sw00762535000msufc0869.fits
SUN_POSTN:       114.05d {+07h 36m 13s}  +21.60d {+21d 35' 46"}
SUN_DIST:         79.46 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.41d {+23h 41m 38s}   -4.84d {-04d 50' 31"}
MOON_DIST:        39.73 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.75,-54.27 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        All 4 attachments are included.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:44:20 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     762535,   Seg_Num: 0
POINT_RA:         34.345d {+02h 17m 23s} (J2000)
POINT_DEC:        +1.989d {+01d 59' 20"} (J2000)
ROLL:            68.381d
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45602.44 SOD {12:40:02.44} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     521728821
X_OFFSET:        830 [pixels]
Y_OFFSET:        861 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       990
Y_GRB_POS:       1021
BINNING_INDEX:   1
IM_URL:          sw00762535000msuni0889.fits
SUN_POSTN:       114.05d {+07h 36m 13s}  +21.60d {+21d 35' 46"}
SUN_DIST:         79.46 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.42d {+23h 41m 40s}   -4.84d {-04d 50' 22"}
MOON_DIST:        39.72 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.75,-54.27 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 14 Jul 17 12:44:35 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     762535,   Seg_Num: 0
POINT_RA:         34.345d {+02h 17m 23s} (J2000)
POINT_DEC:        +1.989d {+01d 59' 20"} (J2000)
ROLL:            68.381d
IMG_START_DATE:  17948 TJD;   195 DOY;   17/07/14
IMG_START_TIME:  45602.44 SOD {12:40:02.44} UT,   869.8 [sec] since BAT Trigger Time
FILTER:          7, U
EXPOSURE_ID:     521728821
X_OFFSET:        830 [pixels]
Y_OFFSET:        861 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       990
Y_GRB_POS:       1021
BINNING_INDEX:   1
IM_URL:          sw00762535000msuni0889.fits
SUN_POSTN:       114.05d {+07h 36m 13s}  +21.60d {+21d 35' 46"}
SUN_DIST:         79.46 [deg]   Sun_angle= 5.3 [hr] (West of Sun)
MOON_POSTN:      355.42d {+23h 41m 41s}   -4.84d {-04d 50' 19"}
MOON_DIST:        39.72 [deg]
MOON_ILLUM:      74 [%]
GAL_COORDS:      161.75,-54.27 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:       32.77,-11.10 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the Window Position in the Mode Command.  
COMMENTS:        The image has 2x2 binning (compression).  
COMMENTS:        All 4 attachments are included.

GCN Circular #21340
A. D'Ai (INAF-IASFPA), D. N. Burrows (PSU), A. Cholden-Brown (PSU), V. D'Elia (ASDC), J. A. Kennea (PSU), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), F. E. Marshall (NASA/GSFC), K. L. Page (U Leicester), D. M. Palmer (LANL) and B. Sbarufatti (INAF-OAB/PSU) report on behalf of the Swift Team:
At 12:25:32 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 170714A (trigger=762535). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 34.321, +1.987 which is
```
   RA(J2000) = 02h 17m 17s
   Dec(J2000) = +01d 59' 14"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). As is usual with an image trigger, the available BAT light curve shows no significant structure.
The XRT began observing the field at 12:32:05.3 UT, 392.7 seconds after the BAT trigger. XRT found a bright, uncatalogued X-ray source located at RA, Dec 34.3498, 1.9901 which is equivalent to:
```
   RA(J2000)  = +02h 17m 23.95s
   Dec(J2000) = +01d 59' 24.4"
```
with an uncertainty of 5.0 arcseconds (radius, 90% containment). This location is 104 arcseconds from the BAT onboard position, within the BAT error circle. No event data are yet available to determine the column density using X-ray spectroscopy.
UVOT took a finding chart exposure of 150 seconds with the U filter starting 869 seconds after the BAT trigger. No credible afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The typical 3-sigma upper limit has been about 19.2 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. The list of sources is typically complete to about 18.0 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.03.
Burst Advocate for this burst is A. D'Ai (antonino.dai AT ifc.inaf.it). 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 Circular #21341
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) report on behalf of the Swift-XRT team.
Using 641 s of XRT Photon Counting mode data and 1 UVOT images for GRB 170714A, 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 = 34.34983, +1.99204 which is equivalent to:
```
RA (J2000): 02h 17m 23.96s
Dec (J2000): +01d 59' 31.3"
```
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 Circular #21343
P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. Cholden-Brown (PSU), S. J. LaPorte (PSU), J.A. Kennea (PSU), A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), S.L. Gibson (U. Leicester) and A. D'Ai report on behalf of the Swift-XRT team:
We have analysed 8.8 ks of XRT data for GRB 170714A (D'Ai et al. GCN Circ. 21340), from 383 s to 22.6 ks after the BAT trigger. The data comprise 1.3 ks 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 Evans et al. (GCN Circ. 21341). The late-time light curve (from T0+5.0 ks) is consistent with a constant source of mean count rate 1.4e+01 ct/sec. A power-law fit gives an index of 1.7 (+1.8, -2.8).
A spectrum formed from the WT mode data can be fitted with an absorbed power-law with a photon spectral index of 1.588 (+/-0.018). The best-fitting absorption column is 9.3 (+/-0.6) x 10^20 cm^-2, in excess of the Galactic value of 3.6 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has a photon index of 1.73 (+/-0.05) and a best-fitting absorption column of 9.0 (+/-1.5) x 10^20 cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from this spectrum is 3.9 x 10^-11 (4.4 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
```
Total column:	     9.0 (+/-1.5) x 10^20 cm^-2
Galactic foreground: 3.6 x 10^20 cm^-2
Excess significance: 6.1 sigma
Photon index:	     1.73 (+/-0.05)
```
The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00762535.
This circular is an official product of the Swift-XRT team.
GCN Circular #21345
D. A. Kann, A. de Ugarte Postigo, L. Izzo, and C. C. Thoene (HETH/IAA-CSIC) report:
GRB 170714A (D'Ai et al. GCN #21340) exhibits very variable behavior in its X-ray light curve beyond what is reported by D'Avanzo et al. (GCN #21343). We especially point out a very rapid decay at ~ 18ks, from ~5 ct/s to 0.01 ct/s in about 1.3 ks. Even after this steep decay, which is a typical sign of central-engine turn-off, the XRT light curve shows flaring activity of a factor of ~5. All this activity is usually the sign of an active central engine.
This highly variable behavior is reminiscent of two types of sources: Ultra-long GRBs like GRBs 101225A, 111209A and 130925A (e.g., Thoene et al., Nature, 480, 72; Gendre et al., ApJ, 766, 30; Levan et al., ApJ, 781, 13; Greiner et al., A&A, 568, A75; Kann et al., A&A, submitted, arXiv:1706.00601) or relativistic tidal disruption events such as Sw J1644 (e.g., Levan et al., Science, 333, 199).
So far no optical source has been reported, and the X-ray afterglow shows signs of additional absorption (D'Avanzo et al., GCN #21343), which may be indicative of a reddened source in the center of its host and therefore a RTDE. On the other hand, the source is significantly brighter than Sw J1644, and no obvious host galaxy is seen in SDSS or PanSTARRS pre-imaging. The hosts of GRBs 101225A and 111209A were also very faint, and GRB 130925A showed very strong absorption.
If this event is an ULGRB, the flaring activity persists for nearly 40ks until now, making it significantly longer than even GRB 111209A.
Despite the inclement visibility, observations of this source are strongly encouraged.
GCN Circular #21346
A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D. A. Kann L. Izzo, C. C. Thoene (HETH/IAA-CSIC), N. Castro-Rodriguez (GTC, IAC, ULL), A. Marante, J. A. Melian (GTC) report:
We observed the field of GRB 170714A (D'Ai et al. GCN 21340), an ULGRB or RTDE candidate (Kann et al., GCN 21345) with OSIRIS at the 10.4m GTC telescope in La Palma (Spain). Observations consisted in several short exposures in i and z filters. The observations were not easy, as the field was located 30 deg away from the 68% illuminated Moon, implying a very high background.
In the combined z-band frame, with mean epoch at 05:10:24 UT (16.75 hr after the burst) we detect a single object within the refined XRT error box (Evans et al. GCN 21341) which is not present in PanSTARRS imaging, with coordinates (J2000):
```
R.A.: 02:17:23.99
Dec.: +01:59:29.51
```
and a magnitude of z(AB)=22.3+/-0.2, which we identify as the possible GRB afterglow, although we cannot make any statement about variability at this time. In our preliminary analysis we do not detect the object in any other band, implying a possible strong reddening.
Further follow up, especially in NIR bands is encouraged.
GCN Circular #21347
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), J. R. Cummings (CPI), A. D'Ai (INAF-IASFPA), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), T. Sakamoto (AGU), M. Stamatikos (OSU), 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 170714A (trigger #762535) (D'Ai et al., GCN Circ. 21340). The BAT ground-calculated position is RA, Dec = 34.322, 1.962 deg which is
```
  RA(J2000)  =  02h 17m 17.3s
  Dec(J2000) = +01d 57' 43.3"
```
with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment). The partial coding was 61%.
The mask-weighted light curve shows continuous weak emission that starts at ~ T-70 s and lasts beyond the end of the event data (T+963 s).
The time-averaged spectrum from T-72.9 to T+464.4 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.76 +- 0.17. The fluence in the 15-150 keV band is 2.8 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+262.88 sec in the 15-150 keV band is 0.4 +- 0.2 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/762535/BA/
GCN Circular #21350
P. D'Avanzo, A. Melandri (INAF-OAB), V. D'Elia (INAF/OAR & ASI/ASDC), G. Mainella, W. Boschin (INAF-TNG) report on behalf of the CIBO collaboration:
We observed the field of GRB 170714A (D'Ai et al. GCN 21340) with the 3.6m Telescopio Nazionale Galileo (TNG) equipped with NICS. Observations were carried out in the near-infrared with the J filter under poor weather conditions (clouds and calima). Observations started on Jul 16 at 04:05:03 UT (~1.65 days after the burst) and consisted in a series of images for a total exposure time of 17 minutes.
No source is detected in the refined XRT error circle (Evans et al. GCN 21341). In particular we could not detect the candidate afterglow reported by de Ugarte Postigo et al. (GCN. 21346).
For the coadded image we estimate a preliminary 3sigma upper limit of J > 19.6 mag (AB, calibrated against the 2MASS catalogue).
GCN Circular #21351
F. E. Marshall (NASA/GSFC) and A. D'Ai (INAF-IASFPA) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 170714A 384 s after the BAT trigger (D'Ai et al., GCN Circ. 21340). There is weak evidence for a fading source consistent with the position of the z-band afterglow candidate reported by de Ugarte Postigo et al. (GCN Circ. 21346). Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
v                  384         1695          175         >18.6
b                  496         1644          155         20.0 +/- 0.33
b                 5390        24672         1011         >20.3
u                  471         1619          284         20.1 +/- 0.35
u                 5185        30412         2351         20.4 +/- 0.18
u                81432        92912         1509         >20.7
w1                 446         1594          136         >21.0
m2                6006        29000         2637         >20.9
w2                5596        34449         3032         >22.0
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.03 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #21352
A. Horesh (HUJI), S. B. Cenko (NASA/GSFC), A. Levan (U. Warwick), and N. Tanvir (U. Leicester) report:
We observed the ultra-long gamma-ray burst (T90 > 1000s; D=E2=80=99Ai et al. GCN 21340; Evans et al. GCN 21341; Kann et al. GCN 21345; Palmer et al. GCN 21347) with the Jansky Very Large Array (VLA). Our observation was undertaken on 2017 July 16 in the C configuration.
We do not detect radio emission at the enhanced XRT position of the source, with a 3 sigma detection limit of 75 micro-Jy at a central frequency of 7.5 GHz.
Future VLA observations are planned under our program to search for late- time emission.
We thank the VLA staff for scheduling this target of opportunity.
GCN Circular #21353
F. E. Marshall (NASA/GSFC) reports on behalf of the Swift/UVOT team:
Some of the Swift UVOT exposures of GRB 170714A previously reported by Marshall and D'Ai (GCN Circular 21351) contain readout streaks due to nearby bright sources. These streaks make the determination of magnitudes very difficult, and this effect was not accounted for in the previous analysis. The affected exposures have been removed from the corrected table given below. As a result, the most significant detection of a source with UVOT has been removed, and there is now only weak evidence for a UVOT source at the position of the z-band afterglow candidate reported by de Ugarte Postigo et al. (GCN Circ. 21346).
Preliminary detections and 3-sigma upper limits using the UVOT photometric system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:
```
Filter         T_start(s)   T_stop(s)      Exp(s)         Mag
v                  397         1695          175         >18.6
b                  496         1644          155         20.0 +/- 0.33
b                92917        93309          382         >20.3
u                  471         1619          284         20.1 +/- 0.35
u                81432        92912         1509         >20.7
w1                 446         1594          136         >21.0
m2               76276        98985         2438         >21.3
w2               74458        86274         1771         >21.5
```
I apologize for any confusion caused by the earlier report.
GCN Circular #21356
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D.A. Kann=20 (HETH/IAA-CSIC), S. Schulze (Weizmann Institute), L. Izzo,=20 C.C. Thoene (HETH/IAA-CSIC) and M. Krips (IRAM) report:
We observed the field of GRB 170714A (D'Ai et al. GCN 21340)=20 using the NOrthern Extended Millimeter Array (NOEMA, Plateau=20 de Bure, France) tuned at 92.5 GHz. Observations were=20 performed between 3:10 and 5:15 UT on 17 July 2017 (2.66 days=20 after the burst) and consisted of 1.33 hr on target with a bandwidth=20 of 3.6 GHz and using 8 antennas.
We do not detect any source consistent with the afterglow position=20 (de Ugarte Postigo et al. GCN 21346) down to a 3-sigma limit of=20 150 uJy. We do note the presence of an unrelated source 12=E2=80=9D=20 Northwest of the afterglow position with a flux density of ~0.19 mJy,=20 which is coincident with an extended source in our GTC images.
This burst has been proposed to be either an ultra-long GRB or a relativistic tidal-disruption event (Kann et al., GCN 21345). We=20 note that this deep non-detection, together with the non-detection=20 from the VLA (Horesh et al. GCN 21352) are consistent with a=20 scenario of an ULGRB like GRBs 101225A, 111209A and 130925A,=20 which have been faint at radio wavelengths (Frail, GCN 11550,=20 Zauderer et al., GCN 11770; Hancock et al., GCNs 12664, 12804;=20 Horesh et al. 2015, ApJ, 812, 86). Relativistic tidal-disruption events=20 such as Sw J1644 and SwJ2058 have been found to be much=20 brighter in radio wavelengths (e.g., Zauderer et al. 2011, Nature,=20 476, 425, Berger et al. 2012, ApJ, 748, 36, Zauderer et al., 2013,=20 ApJ, 767, 152; Cenko et al. 2012, ApJ, 753, 77).
GCN Circular #21359
A. de Ugarte Postigo (HETH/IAA-CSIC, DARK/NBI), D.A. Kann, L. Izzo, C.C. Thoene (HETH/IAA-CSIC), G. Lombardi S. Geier (GTC, IAC-ULL), A. Garcia, A. Perez (GTC) report:
Following the detection of the afterglow (de Ugarte Postigo et al. GCN 21346) of the ultra-long GRB 170714A (D'Ai et al. GCN 21340, Kann et al. GCN 21345) we obtained further NIR and optical observations on 19 and 20 of July, with detections in r, i, z, and H-bands. An object is still observed at the position earlier reported, indicating an important host galaxy contribution.
On 21 July, at 4:53 UT (5.69 days after the burst) we obtained spectroscopy of the afterglow/host galaxy with OSIRIS at the 10.4m GTC telescope (La Palma, Spain). Observations consisted of 4x900 s with grism R1000R, covering the range between 5100 and 10000 AA.
The combined spectrum shows a weak trace with several superimposed emission lines, which we interpret as due to [OII], [OIII] and H-beta, through which we derive a redshift for the host galaxy, and hence for GRB 170714A, of 0.793.
GCN Circular #21360
R. Ricci (INAF/IRA-Bologna), M. Wieringa (ATNF,CSIRO), L. Piro(INAF/IAPS), E. Troja(NASA/GSFC), K. Bannister (ATNF,CSIRO) and B. Gendre (Virgin Islands University) report:
We observed the ultra-long gamma-ray burst GRB170714A (D'Ai' et al. GCN 21340; Evans et al. GCN 21341; Kann et al. GCN 21345; Palmer et al. GCN 21347) with ATCA on 2017 July 20 at 17 and 21 GHz.
We detect a source ~7" northward of the position of the GRB optical counterpart (de Ugarte Postigo et al. GCN 21346). Given the ATCA configuration, this position is consistent at about 2.5 sigma with the GRB optical counterpart. However, we cannot exclude contamination from the source detected at higher frequency by NOEMA (de Ugarte Postigo et al., GCN 21356), thus we conservatively estimate an upper limit of ~ 50uJy at 19GHz to the radio emission from the GRB.
Future ATCA observations are planned under our program on ultralong GRBs (PI:L. Piro).
We thank the ATCA staff for scheduling this target of opportunity.
GCN Circular #21379
B. Gendre (UVI, USA), L. Piro (IAPS/INAF, Italy), E. Troja (GSFC, USA), R. Ricci (INAF/IRA-Bologna), M. Wieringa (ATNF,CSIRO), K. Bannister (ATNF,CSIRO) report:
We observed the field of GRB 170714A (D'Ai et al., GCN 21340) with XMM-Newton between 370,993 and 506,293 seconds post-trigger under our XMM program on ultralong GRBs (PI: Piro).
The X-ray afterglow is clearly visible during the whole observation, at the position:
```
RA: 2h17m24.02s
DEC: +1d59'28.51"
```
with an error of 1.3" (statistic + systematic, 90% confidence), consistent with the position of the optical counterpart (de Ugarte Postigo et al. GCN 21346) and of XRT (Evans et al. GCN 21341).
The observed mean X-ray flux(0.3-10 keV) is 3.7e-14 erg/s/cm2
We thank the ESA and XMM SOC staff for performing this TOO trigger.
GCN Circular #21396
E. Troja (NASA/UMCP), L. Piro (INAF/IASF), B. Gendre (UVI) report on behalf of a larger collaboration:
We observed the field of the ultralong GRB 170714A (D'Ai et al., GCN 21340) with the Chandra X-ray Observatory beginning on 2017 Jul 28.67 UT (14 days post-burst) for a total exposure of 14.9 ks. We clearly detect the GRB counterpart with coordinates:
```
RA(J2000) = 02:17:23.97
Dec(J2000) = +01:59:29.72
```
with a 68% uncertainty of 0.5 arcsec. This position is consistent with the XRT position (http://www.swift.ac.uk/xrt_positions/00762535/), and the optical source reported by de Ugarte Postigo et al. (GCN 21346). By adopting the spectral parameters of the Swift/XRT analysis (D'Avanzo et al., GCN 21343), we estimate an average X-ray flux of ~1.1E-14 erg/cm2/s during our observation. This is consistent with a late-time power-law decay of slope ~-1.
We thank Andrea Prestwich, Belinda Wilkes and the CXC staff for rapidly scheduling this observation.
GCN Circular #21424
L. Piro(INAF/IAPS), R. Ricci (INAF/IRA-Bologna), M. Wieringa (ATNF,CSIRO), E. Troja(NASA/GSFC), K. Bannister (ATNF,CSIRO) and B. Gendre (UVI, USA) report:
We carried out a second observation of our monitoring campaign of the field of the ultralong GRB 170714A (D'Ai' et al. GCN 21340; Evans et al. GCN 21341; Kann et al. GCN 21345; Palmer et al. GCN 21347) with ATCA on 2017 Aug 4 for 9 hours at 17 and 21 GHz.
We detect a source at:
```
RA: 02h17m23.96s
Dec: +01:59'32.9"
```
with a 90% error of ~2.5" in DEC and ~0.1" in RA, consistent with the position of the GRB X-ray counterpart by Chandra (Troja et al. GCN 21396) and the optical source reported by de Ugarte Postigo et al. (GCN 21346).
We associate this source to the radio afterglow of the burst. The flux measured at 19 GHz is 71 +/- 19 uJy.
In comparison to the first ATCA observation (Ricci et al. GCN 21360), the present configuration improves significantly the resolution and allows us to distinguish the radio afterglow from the unrelated source associated to the NOEMA observation (de Ugarte Postigo et al., GCN 21356).
We thank the ATCA staff for scheduling this target of opportunity observation.
GCN Circular #21464
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 robotically triggered on the Swift alert for GRB 170714A (D'Ai et al., GCN 21340) 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 2017 Jul 15.11, Jul 18.27, Jul 20.23 and Jul 22.25 (UT) do not reveal any radio source at the XRT location (Evans et al., GCN 21341), with 3sigma upper limits of 279 uJy, 172 uJy, 288 uJy and 210 uJy respectively. These upper limits are consistent with the results from previously-reported radio observations (Horesh et al., GCN 21352; Ricci et al., GCN 21360; Piro et al., GCN 21424).
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/.

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Jochen Greiner, last update: 11-Aug-2017 [Disclaimer]