Gamma-ray Burst 080129

(All information courtesy of the instrument teams.)

Previous IAU Circulars

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Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 29 Jan 08 06:08:07 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     301981,   Seg_Num: 0
GRB_RA:          105.280d {+07h 01m 07s} (J2000),
                 105.378d {+07h 01m 31s} (current),
                 104.676d {+06h 58m 42s} (1950)
GRB_DEC:          -7.827d {-07d 49' 35"} (J2000),
                  -7.839d {-07d 50' 18"} (current),
                  -7.755d {-07d 45' 16"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1323 [image_cnts]
TRIGGER_DUR:     64.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 50-350 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        14494 TJD;    29 DOY;   08/01/29
GRB_TIME:        22005.46 SOD {06:06:45.46} UT
GRB_PHI:         176.81 [deg]
GRB_THETA:        41.50 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.51 [sigma]
MERIT_PARAMS:     +1  +0  +0  +4  +3  -2  +0  +1 +80  +1 
SUN_POSTN:       311.13d {+20h 44m 30s}  -18.09d {-18d 05' 05"}
SUN_DIST:        143.69 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      204.55d {+13h 38m 11s}  -15.14d {-15d 08' 11"}
MOON_DIST:        96.71 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      221.00, -1.42 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      107.61,-30.34 [deg] ecliptic lon,lat of the burst (or transient)
COMMENTS:        SWIFT-BAT GRB Coordinates.  
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 = 330.05,17.84 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 29 Jan 08 06:10:49 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     301981,   Seg_Num: 0
GRB_RA:          105.280d {+07h 01m 07s} (J2000),
                 105.378d {+07h 01m 31s} (current),
                 104.676d {+06h 58m 42s} (1950)
GRB_DEC:          -7.827d {-07d 49' 35"} (J2000),
                  -7.839d {-07d 50' 18"} (current),
                  -7.755d {-07d 45' 16"} (1950)
GRB_DATE:        14494 TJD;    29 DOY;   08/01/29
GRB_TIME:        22005.46 SOD {06:06:45.46} UT
TRIGGER_INDEX:   20000
GRB_PHI:         176.81 [deg]
GRB_THETA:        41.50 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     64.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.51 [sigma]
LC_URL:          sw00301981000msb.lc
SUN_POSTN:       311.13d {+20h 44m 31s}  -18.08d {-18d 05' 03"}
SUN_DIST:        143.69 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      204.57d {+13h 38m 16s}  -15.15d {-15d 08' 43"}
MOON_DIST:        96.73 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      221.00, -1.42 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      107.61,-30.34 [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 = 330.05,17.84 [deg].

GCN Circular #7226
S. Immler (CRESST/GSFC/UMD), D. N. Burrows (PSU), M. M. Chester (PSU), N. Gehrels (NASA/GSFC), S. T. Holland (CRESST/USRA/GSFC), E. A. Hoversten (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL), D. Perez (U Leicester), M. Perri (ASDC), M. Stamatikos (NASA/ORAU) and G. Stratta (ASDC) report on behalf of the Swift Team:
At 06:06:45 UT, the Swift Burst Alert Telescope (BAT) triggered and located a possible GRB 080129 (trigger=301981). The BAT on-board calculated location is RA, Dec 105.280, -7.827 which is
```
   RA(J2000) = 07h 01m 07s
   Dec(J2000) = -07d 49' 35"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve for this event appears to show a duration of about 80 sec with a peak of ~600 counts/sec (15-350 keV), at ~30 sec after the trigger although, as is usual for image triggers, the TDRSS light curve is noisy. The location of the source, 1.4 degrees from the Galactic plane raises the possibility that this is a Galactic transient. Further analysis will require the downlinked data from Malindi.
Because of an Earth limb constraint, the spacecraft did not slew promptly to the BAT position, and so there are no immediate XRT or UVOT data products to analyze. Swift will slew to this position at about T+3006 s, or about 06:56 UT.
Burst Advocate for this burst is S. Immler (immler AT milkyway.gsfc.nasa.gov). 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:     Tue 29 Jan 08 07:00:40 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     301981,   Seg_Num: 0
POINT_RA:        105.247d {+07h 00m 59s} (J2000)
POINT_DEC:        -7.837d {-07d 50' 11"} (J2000)
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25207.77 SOD {07:00:07.77} UT,   3202.3 [sec] since BAT Trigger Time
COUNTS:          27    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 interations.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 29 Jan 08 07:03:06 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     301981,   Seg_Num: 0
POINT_RA:        105.247d {+07h 00m 59s} (J2000)
POINT_DEC:        -7.836d {-07d 50' 10"} (J2000)
POINT_ROLL:      224.384d
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25212.52 SOD {07:00:12.52} UT,   3207.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.525
N_STARS:         176
X_OFFSET:        225 [pixels]
Y_OFFSET:        537 [pixels]
X_MAX:           1184 [pixels]
Y_MAX:           1496 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00301981000msufc3207.fits
SUN_POSTN:       311.17d {+20h 44m 40s}  -18.07d {-18d 04' 28"}
SUN_DIST:        143.64 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      204.98d {+13h 39m 55s}  -15.32d {-15d 19' 13"}
MOON_DIST:        97.11 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      220.99, -1.46 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      107.57,-30.35 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 29 Jan 08 07:03:43 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     301981,   Seg_Num: 0
POINT_RA:        105.247d {+07h 00m 59s} (J2000)
POINT_DEC:        -7.836d {-07d 50' 10"} (J2000)
POINT_ROLL:      224.384d
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25212.52 SOD {07:00:12.52} UT,   3207.1 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        3.525
N_STARS:         176
X_OFFSET:        225 [pixels]
Y_OFFSET:        537 [pixels]
X_MAX:           1184 [pixels]
Y_MAX:           1496 [pixels]
DET_THRESH:      16
PHOTO_THRESH:    9
SL_URL:          sw00301981000msufc3207.fits
SUN_POSTN:       311.17d {+20h 44m 40s}  -18.07d {-18d 04' 28"}
SUN_DIST:        143.64 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      204.98d {+13h 39m 56s}  -15.32d {-15d 19' 20"}
MOON_DIST:        97.12 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      220.99, -1.46 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      107.57,-30.35 [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:     Tue 29 Jan 08 07:04:53 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     301981,   Seg_Num: 0
POINT_RA:        105.247d {+07h 00m 59s} (J2000)
POINT_DEC:        -7.836d {-07d 50' 10"} (J2000)
ROLL:            224.384d
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25212.52 SOD {07:00:12.52} UT,   3207.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     223282815
X_OFFSET:        544 [pixels]
Y_OFFSET:        856 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       704
Y_GRB_POS:       1016
BINNING_INDEX:   1
IM_URL:          sw00301981000msuni3207.fits
SUN_POSTN:       311.17d {+20h 44m 40s}  -18.07d {-18d 04' 27"}
SUN_DIST:        143.64 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      204.99d {+13h 39m 58s}  -15.33d {-15d 19' 34"}
MOON_DIST:        97.13 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      220.99, -1.46 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      107.57,-30.35 [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:     Tue 29 Jan 08 07:05:20 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     301981,   Seg_Num: 0
POINT_RA:        105.247d {+07h 00m 59s} (J2000)
POINT_DEC:        -7.836d {-07d 50' 10"} (J2000)
ROLL:            224.384d
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25212.52 SOD {07:00:12.52} UT,   3207.1 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     223282815
X_OFFSET:        544 [pixels]
Y_OFFSET:        856 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       704
Y_GRB_POS:       1016
BINNING_INDEX:   1
IM_URL:          sw00301981000msuni3207.fits
SUN_POSTN:       311.17d {+20h 44m 40s}  -18.07d {-18d 04' 27"}
SUN_DIST:        143.64 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      205.00d {+13h 39m 59s}  -15.33d {-15d 19' 40"}
MOON_DIST:        97.13 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      220.99, -1.46 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      107.57,-30.35 [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:        If you have elected to receive attachments:  
COMMENTS:        The uvot_sources_image.fits.gz file does not exist; skipping the attachment.

GCN Circular #7227
S. T. Holland (CRESST/USRA/GSFC) reports on behalf of the Swift Team:
UVOT took a 100 s finding chart exposure of the field of the possible GRB 080129 (Immler et al., GCN Circ. 7226) with the white (160-650 nm) filter starting 3207 seconds after the BAT trigger. No 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 3-sigma upper limit at the centre of the BAT position is white ~= 18.5 on the UVOT photometric system (Poole et al. 2008). The 8'x8' region for the list of sources generated on-board covers 100% of the BAT error circle and contains no uncatalogued sources. This list of sources is typically complete to about 18 mag. This field is 1.42 degrees from the Galactic place, and no correction has been made for the expected Galactic extinction corresponding to a reddening of E(B-V) = 1.02.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 29 Jan 08 07:16:02 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     301981,   Seg_Num: 0
GRB_RA:          105.2849d {+07h 01m 08.3s} (J2000),
                 105.3824d {+07h 01m 31.7s} (current),
                 104.6813d {+06h 58m 43.5s} (1950)
GRB_DEC:          -7.8463d {-07d 50' 46.6"} (J2000),
                  -7.8582d {-07d 51' 29.4"} (current),
                  -7.7743d {-07d 46' 27.5"} (1950)
GRB_ERROR:       2.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25224.00 SOD {07:00:24.00} UT,   3218.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       311.18d {+20h 44m 42s}  -18.07d {-18d 04' 20"}
SUN_DIST:        143.66 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      205.08d {+13h 40m 20s}  -15.36d {-15d 21' 48"}
MOON_DIST:        97.16 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      221.02, -1.43 [deg] galactic lon,lat of the burst
ECL_COORDS:      107.62,-30.36 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values, flux and significance fields are not valid  
COMMENTS:        This position was automatically generated on the ground using  
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper.php for details.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 29 Jan 08 07:16:06 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     301981,   Seg_Num: 0
GRB_RA:          105.2849d {+07h 01m 08.3s} (J2000),
                 105.3824d {+07h 01m 31.7s} (current),
                 104.6813d {+06h 58m 43.5s} (1950)
GRB_DEC:          -7.8463d {-07d 50' 46.6"} (J2000),
                  -7.8582d {-07d 51' 29.4"} (current),
                  -7.7743d {-07d 46' 27.5"} (1950)
GRB_ERROR:       2.9 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       1.00e-10 [erg/cm2/sec]
GRB_SIGNIF:      10.00 [sigma]
IMG_START_DATE:  14494 TJD;    29 DOY;   08/01/29
IMG_START_TIME:  25224.00 SOD {07:00:24.00} UT,   3218.5 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:       311.18d {+20h 44m 42s}  -18.07d {-18d 04' 20"}
SUN_DIST:        143.66 [deg]   Sun_angle= -10.3 [hr] (East of Sun)
MOON_POSTN:      205.08d {+13h 40m 20s}  -15.36d {-15d 21' 49"}
MOON_DIST:        97.16 [deg]
MOON_ILLUM:      59 [%]
GAL_COORDS:      221.02, -1.43 [deg] galactic lon,lat of the burst
ECL_COORDS:      107.62,-30.36 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.  
COMMENTS:        This Notice was ground-generated -- not flight-generated.  
COMMENTS:        TAM values, flux and significance fields are not valid  
COMMENTS:        This position was automatically generated on the ground using 
COMMENTS:        Photon Counting data telemetered via TDRSS (SPER data).  
COMMENTS:        See http://www.swift.ac.uk/sper.php for details.

GCN Circular #7228
M. Perri (ASDC), G. Stratta (ASDC) and D.N. Burrows (PSU) report on behalf of the Swift XRT team:
The Swift XRT began observing the possible GRB 080129 (trigger #301981, Immler et al., GCN Circ. 7226) at 07:00:08 UT, about 53 min after the BAT trigger.
Analysis of prompt downlinked data finds an uncataloged X-ray source located at RA, Dec 105.2848, -7.8463 which is
```
   RA(J2000) = 07 01 8.35
   Dec(J2000) = -07 50 46.8
```
with an uncertainty of 3.3 arcsec (radius, 90% containment). This location is 71 arcseconds from the BAT on-board position, within the BAT error circle (Immler et al., GCN Circ 7226). Further analysis will be reported in a subsequent circular.
This circular is an official product of the Swift XRT Team.
GCN Circular #7229
J. S. Bloom (UC Berkeley) reports on behalf of the larger GRAASP collaboration:
"Automatically triggering off of the original GCN/SWIFT_BAT_POSITION notice for GRB 080129 (GCN 7226), we observed the field with Gemini South + GMOS in the r-band starting at 06:50:21.4 2008-01-29 in a series of 5 dithered exposures of 5 minutes apiece. Consistent with the position of the X-ray source (GCN 7228) we find a point-like object at:
07:01:08.20 -07:50:46.3 (J2000)
(preliminary uncertainty of 300 mas rms relative to 2MASS). We suggest that this is the optical afterglow of GRB 080129 but cannot confirm variability at this time. More observations are encouraged."
We thank the Gemini Staff for conducting these observations.
This message may be cited.
GCN Circular #7230
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team.
Using 399 s of overlapping XRT Photon Counting mode and UVOT V-band data for GRB 080129, 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 = 105.28406, -7.84705 which is equivalent to:
```
RA (J2000): 07h 01m 8.17s
Dec (J2000): -07d 50' 49.4"
```
with an uncertainty of 2.7 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, astro-ph/0708.0986 http://www.swift.ac.uk/xrt_positions/Goad.pdf).
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #7231
T. Kruehler, S. Loew, J.Greiner, C.Clemens, A. Kuepcue Yoldas, A. Yoldas (all MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 080129 observed by Swift (Immler et al. 2008, GCN#7226) simultaneously in grizJHK with GROND mounted at the 2.2m MPI/ESO telescope at La Silla (Chile).
Observations started at 06:11 UT, about 4 min after the GRB.
We find a point source not present in the Digital Sky Survey images inside the Swift/XRT error circle of the X-ray afterglow (Perri et al. 2008, GCN#7228; Goad et al. 2008, GCN#7230).
The coordinates are (+- 0.5 arcsec error):
```
RA (2000.0) = 07h 01m 08.2s    
Decl. (2000.0) = -07d 50' 47'
```
consistent with the optical source reported by J. S. Bloom (GCN#7229).
We estimate magnitudes of 22.8 (r), 21.5 (i), 20.6 (z), 18.9 (J), 18.1 (H) and 17.0 (K) calibrated against USNO and 2MASS field stars. These magnitudes are not corrected for galactic extinction.
The source is fading by about 0.5 mag during the first 90 min, suggesting it to be the optical/NIR afterglow of GRB 080129.
GCN Circular #7232
T. Kruehler, S. Loew, J.Greiner, C.Clemens, A. Kuepcue Yoldas, A. Yoldas (all MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 080129 observed by Swift (Immler et al. 2008, GCN#7226) simultaneously in grizJHK with GROND mounted at the 2.2m MPI/ESO telescope at La Silla (Chile).
Observations started at 06:11 UT, about 4 min after the GRB.
We find a point source not present in the Digital Sky Survey images inside the Swift/XRT error circle of the X-ray afterglow (Perri et al. 2008, GCN#7228; Goad et al. 2008, GCN#7230).
The coordinates are (+- 0.5 arcsec error): RA (2000.0) = 07h 01m 08.2s Decl. (2000.0) = -07d 50' 47' consistent with the optical source reported by J. S. Bloom (GCN#7229).
We estimate magnitudes of 22.8 (r), 21.5 (i), 20.6 (z), 18.9 (J), 18.1 (H) and 17.0 (K) calibrated against USNO and 2MASS field stars. These magnitudes are not corrected for galactic extinction.
The source is fading by about 0.5 mag during the first 90 min, suggesting it to be the optical/NIR afterglow of GRB 080129.
GCN Circular #7233
D. A. Perley and J. S. Bloom (UC Berkeley) report on behalf of the GRAASP collaboration:
Preliminary photometry of our first series of r-band observations of the candidate afterglow of GRB 080129 (Immler et al., GCN 7226; Bloom, 7229) yields the following magnitudes, calibrated using three DSS stars*:
```
t=44 min: R = 22.93 +/- 0.06
t=50 min: R = 22.86 +/- 0.05
t=56 min: R = 22.78 +/- 0.04
t=62 min: R = 22.56 +/- 0.04
t=68 min: R = 22.87 +/- 0.05
```
As these magnitudes are approximately consistent with the value reported by Greiner et al. (GCN 7231/7232) we do not confirm general fading behavior of this source over the interval of our observations. However, we note that the fourth exposure shows statistically significant evidence of a short-lived rebrightening. While an instrumental cause has not been ruled out, given the location in the Galactic plane of the source and the very slow fading reported by Greiner et al. (0.5 mag from 4 to ~94 minutes, atypical of extragalactic GRBs), it is possible that the GRB may be an analog of GRB 070610 / SWIFT J195509.6+261406 (Pagani et al., GCN 6489; Kasliwal et al. 2007, arXiv:0708.0226), which showed extensive short-time scale early-time variability above a nearly-constant baseline. Further observations (including rapid-time-series optical observations), and further analysis of the X-ray afterglow, are encouraged to further investigate the nature of this source.
---
*Calibration stars are:
```
ra            dec            R2
07:01:10.5033 -07:50:24.020  17.130
07:01:07.7333 -07:51:24.620  17.040
07:01:04.7193 -07:50:46.690  17.310
```
GCN Circular #7234
Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 080129 detected by SWIFT (trigger 301981) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile.
The observations started 352.7s after the GRB trigger (270.9s after the notice). The elevation of the field decreased from from 42 degrees above horizon and weather conditions were good.
The date of trigger : t0 = 2008-01-29T06:06:45.216
The fiirst image is 90.0s exposure in tracking mode. We do not detect any OT with a limiting magnitude of: t0+352.7s to t0+442.7s : R > 16.4
We co-added a series of exposures: t0+448.5s to t0+1039.0s : R > 18.3
Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
N.B. Galactic coordinates are lon=220.9983 lat= -1.4244 and the galactic extinction in R band is about 9 magnitudes estimated from D. Schlegel et al. 1998ApJ...500..525S.
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GCN Circular #7235
S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), S. Immler (CRESST/GSFC/UMD), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU) (i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from recent telemetry downlinks, we report further analysis of BAT GRB 080129 (trigger #301981) (Immler, et al., GCN Circ. 7226). The BAT ground-calculated position is RA, Dec = 105.297, -7.840 deg which is
```
   RA(J2000)  = 07h 01m 11.2s 
   Dec(J2000) = -7d 50' 24" 
```
with an uncertainty of 2.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 46%.
The mask-weighted light curve shows a single borad peak stsrting at ~T-20 sec, peaking at ~T+20, and ending at ~T+50. T90 (15-350 keV) is 48 +- 10 sec (estimated error including systematics).
The time-averaged spectrum from T-15.0 to T+49.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.34 +- 0.26. The fluence in the 15-150 keV band is 8.9 +- 1.4 x 10^-07 erg/cm2. The 1-sec peak photon flux measured from T+24.50 sec in the 15-150 keV band is 0.2 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90% confidence level.
The majority of the indicators say this is a GRB, but at this time we can not rule out a galactic source explanation for this trigger.
The results of the batgrbproduct analysis are available at http://gcn.gsfc.nasa.gov/notices_s/301981/BA/
GCN Circular #7236
M.Cwiok, W.Dominik, G.Kasprowicz, A.Majcher, A.Majczyna, K.Malek, L.Mankiewicz, M.Molak, K.Nawrocki, L.W.Piotrowski, D.Rybka, M.Sokolowski, J.Uzycki, G.Wrochna, A.F.Zarnecki on behalf of "Pi of the Sky" collaboration http://grb.fuw.edu.pl
"Pi of the Sky" apparatus located at Las Campanas Observatory imaged the region of GRB 080129 from 6:09:21 UT, i.e. 155s after the GRB (74s after the trigger), with 10s exposures (IR-cut filter only). No new object has been detected within the XRT error box.
Limiting magnitude for 10s exposures is >11.8 mag. The limit for 20 coadded images is >12.5 mag.
GCN Circular #7238
W. Li and A. V. Filippenko, University of California, Berkeley, on behalf of the KAIT GRB team, report:
We imaged the field of GRB 080129 detected by Swift (trigger 301981; Immler et al. GCN 7226) with the robotic 0.76-m Katzman Automatic Imaging Telescope (KAIT) at Lick Observatory. The automatic sequence was not executed due to poor weather, but a manual sequence was observed remotely. In total, 14 x 20 s unfiltered observations were observed. Our first 20 s image started at 6:11:31 UT, 286 s after the GRB trigger. We did not detect the optical/NIR afterglow candidate reported by Bloom (GCN 7229) and Kruehler et al. (GCN 7231) to a limiting magnitude of 17.9 (calibrated to USNO B1). A 200 s co-added image with the middle exposure time at 643 s after the GRB trigger did not detect the afterglow candidate to a limiting magnitude of 20.0.
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GCN Circular #7240
G. Stratta (ASDC), M. Perri (ASDC) and D. N. Burrows (PSU) report on behalf of the Swift-XRT team:
The Swift-XRT began observing GRB 080129 (trigger=301981) on 2008-01-29 at 07:00:17 UT, 53 minutes after the BAT trigger (Immler et al., GCN Circ. 7226).
Using 2045 s of overlapping XRT Photon Counting mode and UVOT v-band data for GRB 080129, we find a refined astrometrically corrected X-ray position (using the XRT-UVOT alignment and matching UVOT field sources to the USNO-B1 catalogue): RA, Dec = 105.284125, -7.846722 which is equivalent to:
```
RA (J2000): 07h 01m 8.19s
Dec (J2000): -07d 50' 48.2"
```
with an uncertainty of 2.0 arcsec (radius, 90% confidence). This is 1.2 arcsec away from the previous position derived from the XRT and UVOT data reported in Goad et al. (GCN Circ. 7230), 51 arcsec from the refined BAT position of Barthelmy et al. (GCN Circ. 7235) and 1.9 arcsec from the Gemini South position (GCN Circ. 7229).
The X-ray light curve from T + 3.2 ks to T + 85.8 ks can be fitted by a broken power law model (chi2 of 39 for 28 degrees of freedom) with a temporal break at about T + 15.5 ks and decay indices alpha1 = 0.6 +/- 0.1 and alpha2 = 1.5 +/- 0.1 before and after the break, respectively.
The 0.3-10 keV spectrum from T + 3.2 ks to T + 32.2 ks is well fit by an absorbed power law (reduced chi2 of 1.02, with 20 degrees of freedom). The best fit photon index is 2.0 +/- 0.1, with an hydrogen column density of (2 +/- 1)e21 cm^-2, in addition to the Galactic column along the line of sight of 6.3e21 cm^-2 (Kalberla et al. 2005). The observed (unabsorbed) flux in the 0.3-10 keV band is 4.2e-12 (8.5e-12) erg cm^-2 s^-1.
The timing and spectral behaviors are completely consistent with those of a typical GRB X-ray afterglow, removing any uncertainty about the nature of this burst.
The predicted XRT count rate 48 hours after the trigger is 1.6e-3 count s^-1, which corresponds to an observed 0.3-10.0 keV flux of 1.3e-12 ergs cm^-2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Circular #7241
A. de Ugarte Postigo (ESO, Santiago), D. Diaz Fraile, F. Aceituno, E.=20 Rodr=EDguez, A.J. Castro-Tirado, J. Gorosabel (IAA-CSIC, Granada) and A. Pozanenko=20 (IKI, Moscow) report on behalf of a larger collaboration:
We have observed GRB 080129 (Immler et al. GCN 7226) with the 1.5m OSN=20 telescope at Sierra Nevada Observatory (Granda, Spain). The observations consist=20 of a series of 625x19s exposures in I-band, and range from 29.8614 Jan 2008 to 30.0166=20 Jan 2008 UT (0.607-0.762 days after the burst). We do not detect any source in the=20 individual frames down to an average limiting magnitude I < 20.3. However, the combined frame=20 does show the source identified by Bloom et al. (GCN 7229) at I ~ 22.1. A finding chart can be seen at: http://www.iaa.es/~deugarte/GRBs/080129/080129_OSN_fc.jpg
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GCN Circular #7246
S. T. Holland (CRESST/GSFC/USRA) and S. Immler (CRESST/UMCP/GSFC) report on the behalf of the Swift UVOT team:
The Swift/UVOT observed the field of GRB 080129 starting 3188 s after the BAT trigger (Immler et al. 2007, GCN Circ. 7226). We do not find any source, in any of the UVOT observations, at the location of the Gemini-South source (Bloom, 2007 GCN Circ. 7229).
The 3-sigma upper limits for detecting a source at this location in the co-added images are:
```
Filter    T_start   T_stop    Exp(s)    Mag (3-sigma upper limit)
-----------------------------------------------------------------
    v         3188   21,457      2023    21.3
    b         4134   28,152      2164    22.2
    u         3929   27,239      1278    21.5
  uvw1        3724   32,166      1182    21.3
  uvm2        3519   22,362      1279    21.2
  uvw2        4545   17,372      1920    21.7
 white        3207   28,940      2856    23.1
-----------------------------------------------------------------
```
This burst occurred 1.43 degrees from the Galactic plane, so the Galactic reddening along the line of sight is highly uncertain. The values quoted above are not corrected for Galactic extinction. All photometry is on the UVOT flight system described in Poole et al. (2008).
0811.4291from 26 Nov 2008
Greiner: A strong optical flare before the rising afterglow of GRB 080129
Abstract: We report on GROND observations of a 40 sec duration (rest-frame) optical flare from GRB 080129 at redshift 4.349. The rise- and decay time follow a power law with indices +12 and -8, respectively, inconsistent with a reverse shock and a factor 10^5 faster than variability caused by ISM interaction. While optical flares have been seen in the past (e.g. GRB 990123, 041219B, 060111B and 080319B), for the first time, our observations not only resolve the optical flare into sub-components, but also provide a spectral energy distribution from the optical to the near-infrared once every minute. The delay of the flare relative to the GRB, its spectral energy distribution as well as the ratio of pulse widths suggest it to arise from residual collisions in GRB outflows \cite{liw08}.If this interpretation is correct and can be supported by more detailed modelling or observation in further GRBs, the delay measurement provides an independent, determination of the Lorentz factor of the outflow.

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Jochen Greiner, last update: 01-Dec-2008 [Disclaimer]