Gamma-ray Burst 060929

(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 29 Sep 06 19:56:39 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.166d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.816d {+29d 48' 59"} (J2000)
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  71793.55 SOD {19:56:33.55} UT,   71793.6 [sec] since BAT Trigger Time
COUNTS:          1    Min_needed= 20
STD_DEV:         0.00   Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER:        0    Max_iter_allowed= 4
ERROR_CODE:      1
COMMENTS:        SWIFT-XRT Nack Position.  
COMMENTS:        No source found in the image.

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 29 Sep 06 19:58:52 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.166d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.816d {+29d 48' 59"} (J2000)
POINT_ROLL:      261.263d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  71796.00 SOD {19:56:36.00} UT,   71796.0 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.573
N_STARS:         118
X_OFFSET:        482 [pixels]
Y_OFFSET:        557 [pixels]
X_MAX:           1441 [pixels]
Y_MAX:           1516 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00231702000msufc181252596.fits
SUN_POSTN:       186.00d {+12h 23m 59s}   -2.59d {-02d 35' 35"}
SUN_DIST:         80.27 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.78d {+17h 55m 08s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.79 [deg]
MOON_ILLUM:      43 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 29 Sep 06 20:00:22 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.166d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.816d {+29d 48' 59"} (J2000)
ROLL:            261.263d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  71796.00 SOD {19:56:36.00} UT,   71796.0 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     181252597
X_OFFSET:        801 [pixels]
Y_OFFSET:        876 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       961
Y_GRB_POS:       1036
BINNING_INDEX:   1
IM_URL:          sw00231702000msuni181252596.fits
SUN_POSTN:       186.00d {+12h 23m 60s}   -2.59d {-02d 35' 36"}
SUN_DIST:         80.27 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.80d {+17h 55m 12s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.79 [deg]
MOON_ILLUM:      43 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [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 29 Sep 06 20:06:14 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.165d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.814d {+29d 48' 51"} (J2000)
POINT_ROLL:      261.261d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  71901.65 SOD {19:58:21.65} UT,   71901.6 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.587
N_STARS:         188
X_OFFSET:        482 [pixels]
Y_OFFSET:        557 [pixels]
X_MAX:           1441 [pixels]
Y_MAX:           1516 [pixels]
DET_THRESH:      11
PHOTO_THRESH:    5
SL_URL:          sw00231702000msufc181252701.fits
SUN_POSTN:       186.00d {+12h 24m 01s}   -2.60d {-02d 35' 42"}
SUN_DIST:         80.26 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.86d {+17h 55m 26s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.79 [deg]
MOON_ILLUM:      43 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 29 Sep 06 20:07:37 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.165d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.814d {+29d 48' 51"} (J2000)
ROLL:            261.261d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  71901.65 SOD {19:58:21.65} UT,   71901.6 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     181252703
X_OFFSET:        801 [pixels]
Y_OFFSET:        876 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       961
Y_GRB_POS:       1036
BINNING_INDEX:   1
IM_URL:          sw00231702000msuni181252701.fits
SUN_POSTN:       186.00d {+12h 24m 01s}   -2.60d {-02d 35' 43"}
SUN_DIST:         80.26 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.87d {+17h 55m 30s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.79 [deg]
MOON_ILLUM:      43 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [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 29 Sep 06 20:07:43 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     231702,   Seg_Num: 0
GRB_RA:          263.1206d {+17h 32m 28.9s} (J2000),
                 263.1856d {+17h 32m 44.5s} (current),
                 262.6386d {+17h 30m 33.2s} (1950)
GRB_DEC:         +29.8356d {+29d 50' 08.1"} (J2000),
                 +29.8311d {+29d 49' 52.0"} (current),
                 +29.8701d {+29d 52' 12.3"} (1950)
GRB_ERROR:       7.2 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       9.99e-12 [erg/cm2/sec]
GRB_SIGNIF:      5.00 [sigma]
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  71793.55 SOD {19:56:33.55} UT,   71793.6 [sec] since BAT Trigger Time
TAM[0-3]:        327.61 237.19 261.35 242.66
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       186.00d {+12h 24m 01s}   -2.60d {-02d 35' 43"}
SUN_DIST:         80.23 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.87d {+17h 55m 30s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.82 [deg]
MOON_ILLUM:      43 [%]
GAL_COORDS:       53.67, 29.18 [deg] galactic lon,lat of the burst
ECL_COORDS:      260.05, 53.04 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values are not valid.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 29 Sep 06 20:16:15 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.165d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.814d {+29d 48' 51"} (J2000)
POINT_ROLL:      261.261d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  72556.26 SOD {20:09:16.26} UT,   72556.3 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        1.286
N_STARS:         190
X_OFFSET:        482 [pixels]
Y_OFFSET:        557 [pixels]
X_MAX:           1441 [pixels]
Y_MAX:           1516 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    5
SL_URL:          sw00231702000msufc181253356.fits
SUN_POSTN:       186.01d {+12h 24m 02s}   -2.60d {-02d 35' 52"}
SUN_DIST:         80.26 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.96d {+17h 55m 51s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.80 [deg]
MOON_ILLUM:      44 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 29 Sep 06 20:17:25 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.165d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.814d {+29d 48' 51"} (J2000)
ROLL:            261.261d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  72556.26 SOD {20:09:16.26} UT,   72556.3 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     181253357
X_OFFSET:        801 [pixels]
Y_OFFSET:        876 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       961
Y_GRB_POS:       1036
BINNING_INDEX:   1
IM_URL:          sw00231702000msuni181253356.fits
SUN_POSTN:       186.01d {+12h 24m 02s}   -2.60d {-02d 35' 53"}
SUN_DIST:         80.26 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.97d {+17h 55m 54s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.80 [deg]
MOON_ILLUM:      44 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [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 29 Sep 06 20:18:04 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.165d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.814d {+29d 48' 51"} (J2000)
POINT_ROLL:      261.261d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  72963.80 SOD {20:16:03.80} UT,   72963.8 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        1.270
N_STARS:         190
X_OFFSET:        482 [pixels]
Y_OFFSET:        557 [pixels]
X_MAX:           1441 [pixels]
Y_MAX:           1516 [pixels]
DET_THRESH:      10
PHOTO_THRESH:    4
SL_URL:          sw00231702000msufc181253763.fits
SUN_POSTN:       186.01d {+12h 24m 02s}   -2.60d {-02d 35' 53"}
SUN_DIST:         80.26 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.98d {+17h 55m 55s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.80 [deg]
MOON_ILLUM:      44 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 29 Sep 06 20:19:14 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     231702,   Seg_Num: 0
POINT_RA:        263.165d {+17h 32m 40s} (J2000)
POINT_DEC:       +29.814d {+29d 48' 51"} (J2000)
ROLL:            261.261d
IMG_START_DATE:  14007 TJD;   272 DOY;   06/09/29
IMG_START_TIME:  72963.80 SOD {20:16:03.80} UT,   72963.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     181253765
X_OFFSET:        801 [pixels]
Y_OFFSET:        876 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       961
Y_GRB_POS:       1036
BINNING_INDEX:   1
IM_URL:          sw00231702000msuni181253763.fits
SUN_POSTN:       186.01d {+12h 24m 03s}   -2.60d {-02d 35' 55"}
SUN_DIST:         80.26 [deg]   Sun_angle= -5.1 [hr] (East of Sun)
MOON_POSTN:      268.99d {+17h 55m 58s}  -28.74d {-28d 44' 08"}
MOON_DIST:        58.80 [deg]
MOON_ILLUM:      44 [%]
GAL_COORDS:       53.66, 29.14 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      260.12, 53.02 [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 Circular #5654
C. B. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), D. N. Burrows (PSU), J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC), S. D. Hunsberger (PSU), J. A. Kennea (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL), P. Romano (INAF-OAB), T. Sakamoto (NASA/ORAU), G. Sato (GSFC/ISAS), P. Schady (MSSL-UCL) and M. Stamatikos (NASA/ORAU) report on behalf of the Swift Team:
At 19:55:01UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 060929 (trigger=231702). Swift slewed immediately to the burst. The on-board location (obtained from a Lightcurve SERS message) is RA,Dec (J2000) 263.164,+29.815 {17h32m39s, 29d48m54s}. Because of a telemetry gap covering the first ~50 sec of the TDRSS messages, we can say nothing about the lightcurve until the full data set is downlinked.
The XRT began taking data at 19:56:33 UT, 92 seconds after the BAT trigger. The XRT on-board centroid algorithm did not find a source in the image, however analysis of prompt downlinked data reveals a faint, uncatalogued point source at the following location:
```
  RA(J2000) =  17h 32m 29.0s
 Dec(J2000) = +29d 50m 08.5s
```
with an estimated uncertainty of 7.3 arcseconds radius (90% containment). This source lies 154 arcseconds from the BAT position.
At this time due to the telemetry gap, only a raw UVOT finding chart image (no sky coordinates) obtained with the white light filter is available. We have attempted to perform pattern matching with the DSS and no obvious afterglow candidate is seen.
GCN Circular #5655
D. Bersier, A. Gomboc, A. Melandri, C. Mundell (Liverpool JMU), E. Rol (Leicester) report on behalf of a larger collaboration
We imaged the field of GRB 060929 (Swift trigger 231702) with the 2m robotic Liverpool Telescope (La Palma), starting at 20:17 UT. Inside the XRT error circle we do not detect any new source down to a magnitude R~20. Further analysis is in progress.
GCN Circular #5656
A. de Ugarte Postigo (IAA-CSIC Granada), P. Kubanek (ASU AV CR ndrejov & ISDC Versoix) & A. Castro-Tirado (IAA-CSIC Granada) on behalf of a larger collaboration report:
"The 0.6m BOOTES-IR and 1.5m telescopes, located at IAA-CSIC Observatorio de Sierra Nevada in Granada (Spain), observed the SWIFT error box for GRB 060929 (Markwardt et al. GCN 5654) starting at 20:17 UT (21 minutes after the burst) in R and I-bands. We do not detect any optical counterpart down to the DSS2 limit. Further analysis is ongoing.
This message is quotable."
GCN Circular #5657
V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, E.Gorbovskoy,D.Kuvshinov, N.Tyurina, P.Gritsyk Sternberg Astronomical Institute, Moscow Union 'Optic'
I.Golubov Kislovodsk Solar Station of the Pulkovo observatory
"MASTER Very Wide Filed Camera located at Kislovodsk Solar Station (http://observ.pereplet.ru, D=70 mm, 400 square degrees) has moved to the Swift-BAT trigger 231702 and it has taken a series of 5s exposures starting 39 s after the Notice Time at 19:57:18 UT (42s after the GRB). The weather is not very good. No new object has been found within the Swift-BAT error box. The limiting magnitude is 12.0m (unfiltered) for single exposures and 12.8m for the sum of 20 images. The message may be cited.
mailto: lipunov@sai.msu.ru
GCN Circular #5658
M. Nekola, F. Munz, J. Strobl (ASu AV CR Ondrejov), A. de Ugarte Postigo (IAA-CSIC Granada) & P.Kubanek (ASu AV CR Ondrejov & ISDC Versoix) on behalf of a larger collaboration reports:
BART 25 cm telescope, located at Ondrejov, Czech Republic, observed position of the SWIFT error box for GRB 060929 (Markwardt et al. GCN 5654) starting at 19:59:12 UT (T + 2 min 39 sec). We did not detect any new source down to R ~ 16.5 mag on first 20 sec image, as well as on combination of first three 20 sec images with mean time 2 min 49 sec down to R ~ 17 mag. Observation was stopped after 20 minutes due to approaching rain.
This message is quotable
GCN Circular #5659
F. Terra, Second University of Roma "Tor Vergata", G. Greco, C. Bartolini, A. Guarnieri, A. Piccioni (Bologna University), D. Nanni (INAF/OAR and Second University of Roma "Tor Vergata"), S. Galleti, S. Bernabei (INAF Bologna) and G. Pizzichini (INAF/IASF Bologna) report:
Using the 152 cm Loiano telescope equipped with the BFOSC camera system, we obtained two 10 min. Rc-band images of the field of GRB060929 (Markwardt et al., GCN 5654) starting at Sept. 29.869 and 29. 878 respectively, seeing 2.6 arcsec. In our co-added images we do not detect any new source inside the XRT error circle. Star 1198-0273615 in the NOMAD catalog, whose magnitude is 20.5, is detected at the 3 sigma level.
GCN Circular #5660
E. Fenimore (LANL), L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), N. Gehrels (GSFC), D. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC) on behalf of the Swift-BAT team:
Using the data set from T-240 to T+321 sec from recent telemetry downlinks, we report further analysis of BAT GRB 060929 (trigger #231702) (Markwardt, et al., GCN Circ. 5654). The BAT ground-calculated position is RA,Dec = 263.158, 29.846 deg {17h 32m 37.9s, 29d 50' 44.3"} (J2000) +- 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 84%.
The mask-weighted lightcurve shows a roughly triangular shaped peak starting at T-5 sec, peaking at T+3 sec, and ending at T+9 sec. T90 (15-350 keV) is 12.4 +- 0.2 sec (estimated error including systematics).
The time-averaged spectrum from T-5.5 to T+9.0 is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.50 +- 0.25. The fluence in the 15-150 keV band is 2.8 +- 0.4 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+2.69 sec in the 15-150 keV band is 0.4 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
GCN Circular #5661
S. Covino (INAF/OAB), A. de Ugarte Postigo (IAA-CSIC), N. Pinilla (TNG), J. Licandro (ING-IAC), on behalf of the CIBO collaboration, report:
We have observed the field of GRB 060929 (Markwardt et al., GCN 5624) with TNG+NICS in the K band from Sep 29, 2006 22:18 UT to 22:33 UT.
No sources down to approximately K=19 (3-sigma u.l.) are present in the XRT error circle.
We acknowledge the excellent support by the TNG staff.
This message is citable.
GCN Circular #5662
D. Palmer (LANL), G. Sato (GSFC/ISAS), S. D. Barthelmy (GSFC), T. Sakamoto (GSFC/ORAU), C. Markwardt (USFC/UMd), N. Gehrels (GSFC) on behalf of the Swift-BAT team:
We have received additional data beyond that used for GCN Circ 5660 (Fenimore, et al) now out to T+1000 sec. We note that there is highly significant emmission in the mask-weighted light curve starting at T+400 sec and ending at T+600 sec. This emission is much softer than the initial emission at T_zero.
Given the spectral signiture of the initial T_zero emission and that there are no known sources at this location (Galactic or extra-Galactic), we still strongly believe that this event is a GRB and not some other non-GRB astrophysical source. We therefore conclude that this late-time emission is a flare.
GCN Circular #5663
A. P. Beardmore (U. Leicester), D. N. Burrows (PSU), K. L. Page (U. Leicester) and C. B. Markwardt (GSFC/UMD) report on behalf of the Swift-XRT team:
We have analysed the first orbit of Swift-XRT data of GRB 060929 (Markwardt et al., GCN 5654).
From 1.9ks of Photon Counting mode data, we derive a refined XRT position of:
```
RA(J2000)  =  17h 32m 29.0s
Dec(J2000) = +29d 50' 08.9"
```
with an error radius of 5.5 arcsec (90% confidence, including boresight uncertainties). This is within 0.4 arcsec of the initial XRT position, and 2.0 arcmin of the refined BAT position (Fenimore et al., GCN 5660).
The XRT light curve from the first orbit shows a giant flare from T+410s to T+1180s, which peaks at a count rate of ~70 count s^-1 at T+535s (where T is the trigger time). This flare is also seen in BAT data (Palmer et al., GCN 5662).
The average Windowed Timing mode spectrum during the flare (from T+476s to T+691s; count rate equal to 36.7 count s^-1) can be described by a absorbed power-law, with a column density of 1.85+/-0.15 e21 cm^-2 and a photon index of 1.86+/-0.05. The 0.3-10.0 keV observed (unabsorbed) flux during this interval is 1.61E-09 (2.15E-09) ergs cm^-2 s^-1.
The underlying non-flare emission is weak (0.07 count s^-1), and can be fit with a power-law of photon index 2.3+1.4-0.8 and an unconstrained column density less than 3.6e21 cm^-2. The 0.3-10.0 keV observed (unabsorbed) flux is 3.3E-12 (5.3E-12) ergs cm^-2 s^-1 The Galactic column in the direction of the source is 3.6e20 cm^-2.
We have insufficient data at this time to predict a later time X-ray decay slope and flux.
This circular is an official product of the Swift-XRT Team.
GCN Circular #5667
S. B. Pandey (UCL-MSSL) and C. B. Markwardt (GSFC/UMD) report on behalf of the Swift-UVOT team:
The Swift UVOT began observing the GRB 060929 field (trigger 231702), 78 seconds after the BAT trigger (GCN 5654, 5660). No new source was detected in the co-added UVOT observations down to the following 3-sigma magnitude upper limits within the refined XRT error circle (GCN 5663):
```
Filter        T_range (s)    Exposure (s)    3sigma UL

V             78  - 2356     950             20.71
B             678 - 2295     136             20.55
U             654 - 2271     156             20.25
W1            630 - 2247     156             19.60
M2            606 - 2223     156             19.83
W2            707 - 2333     156             19.98
White         95  - 2309     273             20.96
```
T_range is calculated from the time of the burst. The upper limits are not corrected for Galactic extinction E(B-V) = 0.048 along the line of sight to the burst.
GCN Circular #5668
K.L. Page, A.P. Beardmore (U. Leicester) & C.B. Markwardt (GSFC/UMD) report on behalf of the Swift-XRT team:
We have now analysed the first 9 orbits of XRT data obtained for GRB 060929 (GCN Circ. 5654; Markwardt et al.). Following the large flare between T+410s and T+1180s reported in GCN Circulars 5662 and 5663 (Palmer et al.; Beardmore et al.), the X-ray afterglow fades with a decay slope of 0.79 +/- 0.08.
Assuming this rate of decay continues, we predict a count rate of 0.0019 count s^-1 at T+24 hours. Using the spectral fit for the data after the flare (photon index = 2.5 +/- 0.9) together with a total column density of 1.8e21 cm^-2 (see GCN Circ. 5663), this corresponds to an observed (unabsorbed) flux of 7.49e-14 (1.41e-13) erg cm^-2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Report 3.1
GCN_Report 3.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_3_1.pdf by C.Markwardt titled: "Swift Observations of GRB 060929"

Back to JG's homepage

Jochen Greiner, last update: 10-Oct-2006 [Disclaimer]