Gamma-ray Burst 080623

(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:     Mon 23 Jun 08 10:32:19 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     315080,   Seg_Num: 0
GRB_RA:          237.660d {+15h 50m 38s} (J2000),
                 237.844d {+15h 51m 22s} (current),
                 236.580d {+15h 46m 19s} (1950)
GRB_DEC:         -62.038d {-62d 02' 16"} (J2000),
                 -62.063d {-62d 03' 46"} (current),
                 -61.887d {-61d 53' 12"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       2728 [cnts]    Image_Peak=116 [image_cnts]
TRIGGER_DUR:     0.512 [sec] 
TRIGGER_INDEX:   40     E_range: 25-100 keV
BKG_INTEN:       34573 [cnts]
BKG_TIME:        37517.11 SOD {10:25:17.11} UT
BKG_DUR:         8 [sec]
GRB_DATE:        14640 TJD;   175 DOY;   08/06/23
GRB_TIME:        37528.44 SOD {10:25:28.44} UT
GRB_PHI:         107.43 [deg]
GRB_THETA:        31.29 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     12.04 [sigma]
IMAGE_SIGNIF:    7.53 [sigma]
MERIT_PARAMS:     +1  +0  +0  +0  +2  +5  +0  +1 +70  +1 
SUN_POSTN:        92.53d {+06h 10m 08s}  +23.42d {+23d 25' 02"}
SUN_DIST:        134.80 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.28d {+21h 49m 07s}  -12.60d {-12d 36' 05"}
MOON_DIST:        78.62 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.34, -6.12 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      250.66,-40.75 [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 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 = 17.29,-18.22 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 23 Jun 08 10:32:58 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     315080,   Seg_Num: 0
GRB_RA:          237.660d {+15h 50m 38s} (J2000),
                 237.844d {+15h 51m 22s} (current),
                 236.580d {+15h 46m 19s} (1950)
GRB_DEC:         -62.038d {-62d 02' 16"} (J2000),
                 -62.063d {-62d 03' 46"} (current),
                 -61.887d {-61d 53' 12"} (1950)
GRB_DATE:        14640 TJD;   175 DOY;   08/06/23
GRB_TIME:        37528.44 SOD {10:25:28.44} UT
TRIGGER_INDEX:   40
GRB_PHI:         107.43 [deg]
GRB_THETA:        31.29 [deg]
DELTA_TIME:      -11.00 [sec]
TRIGGER_DUR:     0.512 [sec] 
SOLN_STATUS:     0x3
RATE_SIGNIF:     12.04 [sigma]
IMAGE_SIGNIF:    7.53 [sigma]
LC_URL:          sw00315080000msb.lc
SUN_POSTN:        92.53d {+06h 10m 08s}  +23.42d {+23d 25' 02"}
SUN_DIST:        134.80 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.28d {+21h 49m 08s}  -12.60d {-12d 35' 56"}
MOON_DIST:        78.63 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.34, -6.12 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      250.66,-40.75 [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 = 17.29,-18.22 [deg].

GCN Circular #7894
T. N. Ukwatta (GSFC/GWU), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester), P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC), O. Godet (U Leicester), S. T. Holland (CRESST/USRA/GSFC), S. D. Hunsberger (PSU), J. A. Kennea (PSU), A. Moretti (INAF-OAB), K. L. Page (U Leicester), D. M. Palmer (LANL), D. Perez (U Leicester), M. Perri (ASDC) and G. Stratta (ASDC) report on behalf of the Swift Team:
At 10:25:28 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080623 (trigger=315080). Swift did not immediately slew because of an Earth observing constraint. The BAT on-board calculated location is RA, Dec 237.660, -62.038, which is
```
   RA(J2000)  =  15h 50m 38s
   Dec(J2000) = -62d 02' 16"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showes several overlapping peaks with a duration of about 25 sec. The peak count rate was ~2500 counts/sec (15-350 keV), at ~7 sec after the trigger.
XRT and UVOT observations will begin when the source comes out of Earth constraint near T+21 minutes.
Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). 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:     Mon 23 Jun 08 10:50:16 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     315080,   Seg_Num: 0
POINT_RA:        237.633d {+15h 50m 32s} (J2000)
POINT_DEC:       -62.051d {-62d 03' 02"} (J2000)
POINT_ROLL:      227.658d
IMG_START_DATE:  14640 TJD;   175 DOY;   08/06/23
IMG_START_TIME:  38855.74 SOD {10:47:35.74} UT,   1327.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.498
N_STARS:         190
X_OFFSET:        350 [pixels]
Y_OFFSET:        626 [pixels]
X_MAX:           1309 [pixels]
Y_MAX:           1585 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00315080000msufc1327.fits
SUN_POSTN:        92.55d {+06h 10m 11s}  +23.42d {+23d 25' 02"}
SUN_DIST:        134.77 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.43d {+21h 49m 42s}  -12.54d {-12d 32' 07"}
MOON_DIST:        78.76 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.32, -6.12 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      250.65,-40.77 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 23 Jun 08 10:50:54 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     315080,   Seg_Num: 0
POINT_RA:        237.633d {+15h 50m 32s} (J2000)
POINT_DEC:       -62.051d {-62d 03' 02"} (J2000)
POINT_ROLL:      227.658d
IMG_START_DATE:  14640 TJD;   175 DOY;   08/06/23
IMG_START_TIME:  38855.74 SOD {10:47:35.74} UT,   1327.3 [sec] since BAT Trigger Time
FILTER:          10, White
BKG_MEAN:        2.498
N_STARS:         190
X_OFFSET:        350 [pixels]
Y_OFFSET:        626 [pixels]
X_MAX:           1309 [pixels]
Y_MAX:           1585 [pixels]
DET_THRESH:      13
PHOTO_THRESH:    7
SL_URL:          sw00315080000msufc1327.fits
SUN_POSTN:        92.55d {+06h 10m 11s}  +23.42d {+23d 25' 02"}
SUN_DIST:        134.77 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.43d {+21h 49m 43s}  -12.53d {-12d 31' 59"}
MOON_DIST:        78.77 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.32, -6.12 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      250.65,-40.77 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Source List.  
COMMENTS:        If you have elected to receive attachments:  
COMMENTS:        The uvot_catalog_srclist.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 23 Jun 08 10:51:44 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     315080,   Seg_Num: 0
POINT_RA:        237.633d {+15h 50m 32s} (J2000)
POINT_DEC:       -62.051d {-62d 03' 02"} (J2000)
ROLL:            227.658d
IMG_START_DATE:  14640 TJD;   175 DOY;   08/06/23
IMG_START_TIME:  38855.74 SOD {10:47:35.74} UT,   1327.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     235910858
X_OFFSET:        669 [pixels]
Y_OFFSET:        945 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       829
Y_GRB_POS:       1105
BINNING_INDEX:   1
IM_URL:          sw00315080000msuni1327.fits
SUN_POSTN:        92.55d {+06h 10m 12s}  +23.42d {+23d 25' 01"}
SUN_DIST:        134.77 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.44d {+21h 49m 45s}  -12.53d {-12d 31' 48"}
MOON_DIST:        78.77 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.32, -6.12 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      250.65,-40.77 [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:     Mon 23 Jun 08 10:52:11 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     315080,   Seg_Num: 0
POINT_RA:        237.633d {+15h 50m 32s} (J2000)
POINT_DEC:       -62.051d {-62d 03' 02"} (J2000)
ROLL:            227.658d
IMG_START_DATE:  14640 TJD;   175 DOY;   08/06/23
IMG_START_TIME:  38855.74 SOD {10:47:35.74} UT,   1327.3 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     235910858
X_OFFSET:        669 [pixels]
Y_OFFSET:        945 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       829
Y_GRB_POS:       1105
BINNING_INDEX:   1
IM_URL:          sw00315080000msuni1327.fits
SUN_POSTN:        92.55d {+06h 10m 12s}  +23.42d {+23d 25' 01"}
SUN_DIST:        134.77 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.44d {+21h 49m 46s}  -12.53d {-12d 31' 42"}
MOON_DIST:        78.77 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.32, -6.12 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      250.65,-40.77 [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 NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 23 Jun 08 10:47:39 UT
NOTICE_TYPE:     Swift-XRT Nack-Position
TRIGGER_NUM:     315080,   Seg_Num: 0
POINT_RA:        237.633d {+15h 50m 32s} (J2000)
POINT_DEC:       -62.051d {-62d 03' 02"} (J2000)
IMG_START_DATE:  14640 TJD;   175 DOY;   08/06/23
IMG_START_TIME:  38851.42 SOD {10:47:31.42} UT,   1323.0 [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.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Mon 23 Jun 08 11:02:46 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     315080,   Seg_Num: 0
GRB_RA:          237.6606d {+15h 50m 38.5s} (J2000),
                 237.8445d {+15h 51m 22.6s} (current),
                 236.5809d {+15h 46m 19.4s} (1950)
GRB_DEC:         -62.0489d {-62d 02' 56.0"} (J2000),
                 -62.0741d {-62d 04' 26.6"} (current),
                 -61.8978d {-61d 53' 51.9"} (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:  14640 TJD;   175 DOY;   08/06/23
IMG_START_TIME:  38874.00 SOD {10:47:54.00} UT,   1345.6 [sec] since BAT Trigger Time
TAM[0-3]:        100.00 100.00 100.00 100.00
AMPLIFIER:       1
WAVEFORM:        31
SUN_POSTN:        92.56d {+06h 10m 13s}  +23.42d {+23d 25' 01"}
SUN_DIST:        134.78 [deg]   Sun_angle= -9.7 [hr] (East of Sun)
MOON_POSTN:      327.53d {+21h 50m 06s}  -12.49d {-12d 29' 22"}
MOON_DIST:        78.84 [deg]
MOON_ILLUM:      80 [%]
GAL_COORDS:      322.33, -6.13 [deg] galactic lon,lat of the burst
ECL_COORDS:      250.67,-40.76 [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/docs.php for details.

GCN Circular #7895
D. Perez (U. Leicester-U. Jaen), K. Page, P. Evans, A. Beardmore (U. Leicester) report on behalf of the Swift XRT Team
The XRT began observing the field at 10:47:31.4 UT, 22.0 minutes after the BAT trigger. Using promptly downlinked data we find a fading, uncatalogued X-ray source located at RA, Dec 237.66083, -62.04897 which is equivalent to:
```
   RA(J2000)  = 15h 50m 38.60s
   Dec(J2000) = -62d 02' 56.3"
```
with an uncertainty of 3.0 arcseconds (radius, 90% containment). This location is 39 arcseconds from the BAT onboard position, within the BAT error circle.
A power-law fit to a spectrum formed from promptly downlinked event data gives a column density consistent with the Galactic value of 2.59e+21 cm^-2 (Kalberla et al. 2005).
GCN Circular #7896
S. T. Holland (CRESST/USRA/GSFC) reports on behalf of the Swift/UVOT Team:
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 1331 seconds after the BAT trigger. No afterglow candidate has been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of the XRT error circle (Perez, et al., 2008, GCN Circ. 7895). The 3-sigma upper limit is 21.1 mag. No correction has been made for the large expected extinction corresponding to E(B-V) of 0.35 mag. The USNO B1.0 star 279-072176 is located 2.07 arcsec from the centre of the XRT error circle.
GCN Circular #7897
Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 080623 detected by SWIFT (trigger 315080) with the TAROT robotic telescope (D=25cm) located at the European Southern Observatory, La Silla observatory, Chile.
The observations started 425.1s after the GRB trigger (14.8s after the notice). The elevation of the field decreased from 12 degrees above horizon and weather conditions were good but only four images of 90s were taken due to the end of the night.
The date of trigger : t0 = 2008-06-23T10:25:28.44
We do not detect any optical transient at the XRT position (Ukwatta et al. GCNC 7894) with the following limiting magnitudes:
The first image is 90.0s exposure: t0+425s to t0+515s : R > 16.2
We co-added the four exposures: t0+425s to t0+802.0s : R > 17.0
This last value is conservative because the star density is high and the spatial sampling of TAROT (i.e. 3.3 arcsec/pix) is not adapted to separate close sources fainter than mag 17.0 at the XRT position.
Magnitudes were estimated with the nearby USNO-B1 stars and are not corrected for galactic dust extinction.
N.B. Galactic coordinates are lon=322.3398 lat= -6.1221 and the galactic extinction in R band is 0.94 magnitudes estimated from D. Schlegel et al. 1998ApJ...500..525S.
This message may be cited.
GCN Circular #7898
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester) report on behalf of the Swift-XRT team.
Using 199 s of overlapping XRT Photon Counting mode and UVOT data for GRB 080623, 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 = 237.66166, -62.04919 which is equivalent to:
```
RA (J2000): 15h 50m 38.80s
Dec (J2000): -62d 02' 57.1"
```
with an uncertainty of 2.4 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 http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an extension of this method.
This circular was automatically generated, and is an official product of the Swift-XRT team.
GCN Circular #7899
W. Baumgartner (GSFC/UMBC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD), D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (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+1390 sec from recent telemetry downlinks, we report further analysis of BAT GRB 080623 (trigger #315080) (Ukwatta, et al., GCN Circ. 7894). The BAT ground-calculated position is RA, Dec = 237.667, -62.044 deg which is
```
   RA(J2000)  =  15h 50m 40.1s 
   Dec(J2000) = -62d 02' 36.7" 
```
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment). The partial coding was 33%.
The mask-weighted light curve shows four overlapping peaks starting at ~T-1 sec and ending at ~T+18 sec. T90 (15-350 keV) is 15.2 +- 5 sec (estimated error including systematics).
The time-averaged spectrum from T-0.7 to T+16.0 sec is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.35 +- 0.15. The fluence in the 15-150 keV band is 1.0 +- 0.1 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from T+7.23 sec in the 15-150 keV band is 2.0 +- 0.3 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/315080/BA/
GCN Circular #7900
D. Perez (U. Leicester-U. Jaen), K.L. Page (U. Leicester), T. N. Ukwatta (GSFC/GWU), report on behalf of the Swift-XRT team:
We have analysed the first three orbits of data obtained for GRB 080623 (Ukwatta et al., GCN Circ. 7894), covering 4.3ks of Photon Counting (PC) mode data. The UVOT-enhanced XRT position was given by Beardmore et al. in GCN Circ. 7898.
The light-curve can be fitted with a single powerlaw with a decay of alpha ~1.0 +/- 0.1.
The first three orbits of PC data can be modelled with an absorbed powerlaw, with Gamma = 2.03 +/- 0.14 and total NH = (0.37 +/- 0.05)x10^22 cm^-2, in excess of the Galactic value of 0.26x10^22 cm^-2.
The observed (unabsorbed) flux over this time interval is 8.05 x10^-12 (1.34x10^-11) erg cm^-2 s^-1. The counts to observed flux conversion is 5.3x10^-11 erg cm^-2 count^-1.
If the light-curve continues to decay at alpha ~ 1.0, the count rate at 24 hours is predicted to be 0.0086 count s^-1, corresponding to an observed flux of 4.5x10^-13 erg cm^-2 s^-1.
This is an official product of the Swift-XRT team.
GCN Circular #7901
A. A. Breeveld (MSSL/UCL) and T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift/UVOT team.
The Swift Ultra-Violet/Optical Telescope (UVOT) began settled observations of GRB 080623 (Ukwatta et al., GCN Circ. 7894) 22.15 minutes after the trigger, as reported in Holland, GCN Circ. 7896. We confirm that no afterglow is detected at the position of the enhanced XRT position (Beardmore et al., GCN Circ. 7898) in the initial finding chart or subsequent summed images.
The following table gives the 3 sigma upper limits in all filters.
```
Filter  T_start(s)  T_stop(s)  Exp(s)  Mag UL (3sig)

white   1329        1428       98.1    >20.4
white   1559        2713       76.9    >20.3
white   8133        8332      196.6    >20.8
v       1436        2598      155.6    >19.0
b       1535        2698      155.5    >19.9
u       1510        2673      155.4    >19.7
uvw1    1486        2648      155.5    >19.4
uvm2    1460        2623      155.6    >19.1
uvw2    1575        2573      136.1    >19.3
```
The values quoted above are in the UVOT photometric system (Poole et al. 2008, MNRAS, 383, 627). No correction has been made for the large expected extinction corresponding to E(B-V) of 0.35 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular #7902
A. Updike (Clemson Univ.), S. Loew, J. Greiner, T. Kruehler, A. Kuepcue Yoldas, A. Yoldas, (all MPE Garching), G. Szokoly (Eoetvoes Univ., Budapest and MPE Garching), report for the GROND team:
We observed the field of GRB 080623 detected by Swift/BAT (Ukwatta et al. 2008, GCN 7894) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP 120, 405), mounted at the 2.2m MPI/ESO telescope at La Silla (Chile). A first epoch started on Jun. 23 at 22:50 UT (12.3 hrs after the GRB) and continued for 2.5 hours; the second epoch was obtained on Jun. 24 at 23:50 UT (mid-time).
We do not detect any new source within the astrometrically corrected XRT position (Beardmore et al. 2008, GCN 7898).
We note that there is a bright star at the border of the XRT error circle and a fainter one just outside the XRT error circle. A finding chart can be found at http://www.mpe.mpg.de/~jcg/grb080623.html . Both objects are visible in DSS2-R and are constant between our two epochs. Image subtraction revealed no hidden sources.
Limiting magnitudes inside the XRT error circle are g'>24.3, r'>23.5, i'>21.8, z'>21.7, J>20.2, H>19.4, K>17.5, calibrated against USNO-B1 and 2MASS stars.

GROND r'-band image of Jun 23, 2008 (left) and DSS2-R (right).
GCN Circular #7909
Y. Terada, M. Tashiro, Y. Urata, K. Onda, A. Endo, N. Kodaka, K. Morigami, T. Sugasahara, W. Iwakiri (Saitama U.), M. Ohno, M. Kokubun, M. Suzuki, T. Takahashi (ISAS/JAXA), Y. Fukazawa, T. Takahashi, T. Uehara, C. Kira, Y. Hanabata (Hiroshima U.), K. Yamaoka, S. Sugita (Aoyama Gakuin U.), Y. E. Nakagawa, T. Tamagawa (RIKEN), T. Enoto, K. Nakazawa, K. Makishima (Univ. of Tokyo), E. Sonoda, M. Yamauchi, H. Tanaka, R. Hara (Univ. of Miyazaki), S. Hong (Nihon U.), on behalf of the Suzaku WAM team, report:
The long GRB 080623 (Swift/BAT trigger #315080 ; Ukwatta et al., GCN 7894) was detected by the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 10:25:28 UT on 23 July 2008 (=T0). The observed light curve shows a multi-peaked structure starting at T0, ending at T0+10 s with a duration (T90) of about 7 seconds. The fluence in 100 - 1000 keV was (1.6 +/- 0.4) E-6 erg/cm^2. The 1-s peak flux measured from T0+ 8 s was 0.5 +/- 0.4 photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0 to T0+10 s is well fitted by a single power-law with a photon index of 2.0 -0.9+1.0 (chi^2/d.o.f = 5.6 / 8) at the 150 - 600 keV bandpass.
All the quoted errors are at statistical 90% confidence level, in which the systematic uncertainties are not included.
The light curves with 1-sec time resolution for this burst will be appeared at the following URL. http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/untrig/grb_table.html
GCN Report 150.1
GCN_Report 150.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_150_1.pdf by T.N. Ukwatta at GSFC/GWU titled: "Final Swift Observations on GRB 080623"

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Jochen Greiner, last update: 18-Jul-2008 [Disclaimer]