Gamma-ray Burst 130627B

(All information courtesy of the instrument teams.)

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 27 Jun 13 12:01:25 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     559139,   Seg_Num: 0
GRB_RA:          181.932d {+12h 07m 44s} (J2000),
                 182.109d {+12h 08m 26s} (current),
                 181.280d {+12h 05m 07s} (1950)
GRB_DEC:         -55.730d {-55d 43' 47"} (J2000),
                 -55.805d {-55d 48' 17"} (current),
                 -55.452d {-55d 27' 05"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       6067 [cnts]    Image_Peak=282 [image_cnts]
TRIGGER_DUR:     2.048 [sec] 
TRIGGER_INDEX:   262     E_range: 25-100 keV
BKG_INTEN:       58150 [cnts]
BKG_TIME:        43213.27 SOD {12:00:13.27} UT
BKG_DUR:         24 [sec]
GRB_DATE:        16470 TJD;   178 DOY;   13/06/27
GRB_TIME:        43250.65 SOD {12:00:50.65} UT
GRB_PHI:         164.49 [deg]
GRB_THETA:        18.73 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     9.84 [sigma]
IMAGE_SIGNIF:    9.71 [sigma]
MERIT_PARAMS:     +1  +0  +0  +1  +2  +0  +0  +1 +28  +0 
SUN_POSTN:        96.54d {+06h 26m 09s}  +23.30d {+23d 18' 03"}
SUN_DIST:        106.70 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:      332.29d {+22h 09m 09s}   -6.12d {-06d 07' 04"}
MOON_DIST:       113.37 [deg]
MOON_ILLUM:      78 [%]
GAL_COORDS:      296.76,  6.62 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      211.59,-48.65 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
COMMENTS:        This is a rate 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 = 152.13,20.47 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 27 Jun 13 12:04:41 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     559139,   Seg_Num: 0
GRB_RA:          181.932d {+12h 07m 44s} (J2000),
                 182.109d {+12h 08m 26s} (current),
                 181.280d {+12h 05m 07s} (1950)
GRB_DEC:         -55.730d {-55d 43' 47"} (J2000),
                 -55.805d {-55d 48' 17"} (current),
                 -55.452d {-55d 27' 05"} (1950)
GRB_DATE:        16470 TJD;   178 DOY;   13/06/27
GRB_TIME:        43250.65 SOD {12:00:50.65} UT
TRIGGER_INDEX:   262
GRB_PHI:         164.49 [deg]
GRB_THETA:        18.73 [deg]
DELTA_TIME:      -57.00 [sec]
TRIGGER_DUR:     2.048 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     9.84 [sigma]
IMAGE_SIGNIF:    9.71 [sigma]
LC_URL:          sw00559139000msb.lc
SUN_POSTN:        96.54d {+06h 26m 09s}  +23.30d {+23d 18' 03"}
SUN_DIST:        106.70 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:      332.32d {+22h 09m 16s}   -6.11d {-06d 06' 25"}
MOON_DIST:       113.39 [deg]
MOON_ILLUM:      78 [%]
GAL_COORDS:      296.76,  6.62 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      211.59,-48.65 [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 a rate 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 = 152.13,20.47 [deg].

GCN Circular #14936
S. R. Oates (UCL-MSSL), S. D. Barthelmy (GSFC), D. N. Burrows (PSU), V. D'Elia (ASDC), P. A. Evans (U Leicester), S. T. Holland (STScI), A. Y. Lien (NASA/GSFC/ORAU), D. Malesani (DARK/NBI), K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU) report on behalf of the Swift Team:
At 12:00:50 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 130627B (trigger=559139). Due to an Earth limb constraint Swift could not immediately slew to the burst. The BAT on-board calculated location is RA, Dec 181.932, -55.730 which is
```
   RA(J2000) = 12h 07m 44s
   Dec(J2000) = -55d 43' 47"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single-peaked structure with a duration of about 40 sec. The peak count rate was ~1300 counts/sec (15-350 keV), at ~0 sec after the trigger.
Due to an observing constraint, Swift will not slew until T0+48.4 minutes. There will be no XRT or UVOT data until this time.
Burst Advocate for this burst is S. R. Oates (samantha.oates AT ucl.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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 27 Jun 13 12:53:27 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     559139,   Seg_Num: 0
POINT_RA:        181.896d {+12h 07m 35s} (J2000)
POINT_DEC:       -55.719d {-55d 43' 09"} (J2000)
IMG_START_DATE:  16470 TJD;   178 DOY;   13/06/27
IMG_START_TIME:  46247.27 SOD {12:50:47.27} UT,   2996.6 [sec] since BAT Trigger Time
COUNTS:          208    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        4    Max_iter_allowed= 4
ERROR_CODE:      2
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        Algorithm did not converge; too many iterations.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 27 Jun 13 13:21:35 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     559139,   Seg_Num: 0
POINT_RA:        181.892d {+12h 07m 34s} (J2000)
POINT_DEC:       -55.721d {-55d 43' 16"} (J2000)
POINT_ROLL:      287.297d
IMG_START_DATE:  16470 TJD;   178 DOY;   13/06/27
IMG_START_TIME:  47005.55 SOD {13:03:25.55} UT,   3754.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.259
N_STARS:         190
X_OFFSET:        319 [pixels]
Y_OFFSET:        630 [pixels]
X_MAX:           1278 [pixels]
Y_MAX:           1589 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00559139000msufc3754.fits
SUN_POSTN:        96.59d {+06h 26m 22s}  +23.30d {+23d 17' 55"}
SUN_DIST:        106.64 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:      333.03d {+22h 12m 08s}   -5.86d {-05d 51' 19"}
MOON_DIST:       113.86 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:      296.74,  6.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      211.56,-48.65 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Thu 27 Jun 13 13:22:03 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     559139,   Seg_Num: 0
POINT_RA:        181.892d {+12h 07m 34s} (J2000)
POINT_DEC:       -55.721d {-55d 43' 16"} (J2000)
POINT_ROLL:      287.297d
IMG_START_DATE:  16470 TJD;   178 DOY;   13/06/27
IMG_START_TIME:  47005.55 SOD {13:03:25.55} UT,   3754.9 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        5.259
N_STARS:         190
X_OFFSET:        319 [pixels]
Y_OFFSET:        630 [pixels]
X_MAX:           1278 [pixels]
Y_MAX:           1589 [pixels]
DET_THRESH:      19
PHOTO_THRESH:    11
SL_URL:          sw00559139000msufc3754.fits
SUN_POSTN:        96.59d {+06h 26m 22s}  +23.30d {+23d 17' 55"}
SUN_DIST:        106.64 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:      333.04d {+22h 12m 09s}   -5.85d {-05d 51' 14"}
MOON_DIST:       113.87 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:      296.74,  6.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      211.56,-48.65 [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:     Thu 27 Jun 13 13:23:14 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     559139,   Seg_Num: 0
POINT_RA:        181.892d {+12h 07m 34s} (J2000)
POINT_DEC:       -55.721d {-55d 43' 16"} (J2000)
ROLL:            287.297d
IMG_START_DATE:  16470 TJD;   178 DOY;   13/06/27
IMG_START_TIME:  47005.55 SOD {13:03:25.55} UT,   3754.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     394031016
X_OFFSET:        638 [pixels]
Y_OFFSET:        949 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       798
Y_GRB_POS:       1109
BINNING_INDEX:   1
IM_URL:          sw00559139000msuni3765.fits
SUN_POSTN:        96.59d {+06h 26m 23s}  +23.30d {+23d 17' 55"}
SUN_DIST:        106.64 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:      333.05d {+22h 12m 12s}   -5.85d {-05d 51' 00"}
MOON_DIST:       113.87 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:      296.74,  6.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      211.56,-48.65 [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:     Thu 27 Jun 13 13:23:34 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     559139,   Seg_Num: 0
POINT_RA:        181.892d {+12h 07m 34s} (J2000)
POINT_DEC:       -55.721d {-55d 43' 16"} (J2000)
ROLL:            287.297d
IMG_START_DATE:  16470 TJD;   178 DOY;   13/06/27
IMG_START_TIME:  47005.55 SOD {13:03:25.55} UT,   3754.9 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     394031016
X_OFFSET:        638 [pixels]
Y_OFFSET:        949 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       798
Y_GRB_POS:       1109
BINNING_INDEX:   1
IM_URL:          sw00559139000msuni3765.fits
SUN_POSTN:        96.59d {+06h 26m 23s}  +23.30d {+23d 17' 55"}
SUN_DIST:        106.64 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:      333.05d {+22h 12m 12s}   -5.85d {-05d 50' 56"}
MOON_DIST:       113.87 [deg]
MOON_ILLUM:      77 [%]
GAL_COORDS:      296.74,  6.62 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      211.56,-48.65 [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 #14938
S. Campana (INAF-OAB), G. Cusumano (INAF-IASF PA), P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester), D.N. Burrows (PSU) and J.A. Kennea (PSU) report on behalf of the Swift-XRT team:
The XRT began observing the field of GRB 130627B at 12:50:47.2 UT, 2996.6 seconds after the BAT trigger. No source was detected in 1.8 ks of promptly downlinked data, which covered 96% of the BAT error circle. We are waiting for the full dataset to detect and localise the XRT counterpart.
GCN Circular #14939
S. R. Oates & M. De Pasquale (UCL-MSSL) report on behalf of the Swift/UVOT Team:
UVOT took a finding chart exposure of 150 seconds with the White filter starting 3754 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 25% of the BAT error circle. The typical 3-sigma upper limit has been about 19.6 mag. The 8'x8' region for the list of sources generated on-board covers 100% of the BAT error circle. The list of sources is typically complete down to about 18 mag. No correction has been made for the expected extinction corresponding to E(B-V) of 0.40.
GCN Circular #14947
P.A. Evans (U. Leicester) & S.R. Oates (MSSL-UCL) report on behalf of the Swift-XRT team:
In 3.3 ks of XRT data for GRB 130627B (Oates et al. GCN Circ. 14936), from 3.7 ks to 11.2 ks after the BAT trigger we find an uncatalogued X-ray sources at RA, Dec = 181.91308, -55.7008 which is equivalent to:
```
RA (J2000): 12 07 39.14
Dec(J2000): -55 42 02.9
```
with an uncertainty of 4.2 arcsec (radius, 90% confidence). The mean count rate in this interval is 8.8(+/-2.0) x 10^-3 ct/sec, and we cannot determine at the present time whether the source is fading.
This circular is an official product of the Swift-XRT team.
GCN Circular #14950
N. P. M. Kuin and S. R. Oates (UCL-MSSL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 130627B 3755 s after the BAT trigger (Oates et al., GCN Circ. No. 14936 and 14939).
No optical afterglow consistent with the XRT position Evans et al. GCN Circ. No. 14947 is detected in the initial UVOT exposures.
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          3755         3905          147         >20.3
white             3755         5137          344         >20.9
v                 3911         5474          320         >19.5
b                 4733         4932          197         >20.1
u                 4526         4726          197         >19.7
w1                4321        11240          757         >20.3
m2                4116        10664         1082         >20.4
w2                5143         5343          197         >19.7
```
The magnitudes in the table are not corrected for the Galactic extinction due to the reddening of E(B-V) = 0.40 in the direction of the burst (Schlegel et al. 1998).
GCN Circular #14952
M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), S. R. Oates (UCL-MSSL), D. M. Palmer (LANL), T. Sakamoto (AGU), G. Sato (ISAS), J. Tueller (GSFC), T. N. Ukwatta (MSU) (i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from the recent telemetry downlink, we report further analysis of BAT GRB 130627B (trigger #559139) (Oates, et al., GCN Circ. 14936). The BAT ground-calculated position is RA, Dec = 181.914, -55.706 deg which is
```
  RA(J2000)  =  12h 07m 39.3s
  Dec(J2000) = -55d 42' 20.3"
```
with an uncertainty of 1.8 arcmin, (radius, sys+stat, 90% containment). The partial coding was 95%.
The mask-weighted light curve shows a single peak starting at ~T-6 sec, peaking at ~T+2 sec, and ending at ~T+22 sec. T90 (15-350 keV) is 28.6 +- 5.8 sec (estimated error including systematics).
The time-averaged spectrum from T-10.5 to T+26.0 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.13 +- 1.03, and Epeak of 47.6 +- 8.7 keV (chi squared 56.72 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 6.1 +- 0.8 x 10^-07 erg/cm2 and the 1-sec peak flux measured from T+1.82 sec in the 15-150 keV band is 0.8 +- 0.2 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.79 +- 0.16 (chi squared 68.34 for 57 d.o.f.). 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/559139/BA/
GCN Circular #14966
P.A. Evans (U. Leicester) and S. R. Oates (UCL-MSSL) report on behalf of the Swift-XRT team:
Swift performed a second epoch observation of GRB 130627B (Oates et al., GCN Circ. 14936) on 2013 July 2nd, collecting 7.3 ks of Photon Counting mode data from T0+390 ks to T0+415 ks. The X-ray object reported by Evans et al. (GCN Circ. 14947) is no longer detected. The 3-sigma upper limit is 1.7 x 10^-3 ct/sec, which is well below the level of 8.8(+/-2.0) x 10^-3 ct/sec at which the source was previously detected.
We therefore confirm that this object was the afterglow of GRB 130627B.
This circular is an official product of the Swift-XRT team.
GCN Report 476.1
GCN_Report 476.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_476_1.pdf by S.Oates at UCL-MSSL titled: "Swift Observations of GRB 130627B"

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Jochen Greiner, last update: 26-Dec-2014 [Disclaimer]