Gamma-ray Burst 080212

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN/BACODINE POSITION NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:35:13 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     303105,   Seg_Num: 0
GRB_RA:          231.107d {+15h 24m 26s} (J2000),
                 231.225d {+15h 24m 54s} (current),
                 230.376d {+15h 21m 30s} (1950)
GRB_DEC:         -22.752d {-22d 45' 06"} (J2000),
                 -22.780d {-22d 46' 48"} (current),
                 -22.576d {-22d 34' 32"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       16148 [cnts]    Image_Peak=301 [image_cnts]
TRIGGER_DUR:     4.096 [sec] 
TRIGGER_INDEX:   298     E_range: 25-100 keV
BKG_INTEN:       144339 [cnts]
BKG_TIME:        63213.43 SOD {17:33:33.43} UT
BKG_DUR:         40 [sec]
GRB_DATE:        14508 TJD;    43 DOY;   08/02/12
GRB_TIME:        63273.46 SOD {17:34:33.46} UT
GRB_PHI:          15.34 [deg]
GRB_THETA:        41.56 [deg]
SOLN_STATUS:     0x3
RATE_SIGNIF:     10.53 [sigma]
IMAGE_SIGNIF:    7.18 [sigma]
MERIT_PARAMS:     +1  +0  +0  +2  +2  -3  +0  +0  -1  +1 
SUN_POSTN:       325.71d {+21h 42m 50s}  -13.73d {-13d 43' 35"}
SUN_DIST:         88.75 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.71d {+02h 02m 50s}  +17.67d {+17d 39' 55"}
MOON_DIST:       160.10 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.18, 27.92 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      234.52, -3.98 [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 = 241.68,-14.05 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:36:51 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     303105,   Seg_Num: 0
GRB_RA:          231.1466d {+15h 24m 35.1s} (J2000),
                 231.2654d {+15h 25m 03.6s} (current),
                 230.4161d {+15h 21m 39.8s} (1950)
GRB_DEC:         -22.7410d {-22d 44' 27.5"} (J2000),
                 -22.7693d {-22d 46' 09.5"} (current),
                 -22.5650d {-22d 33' 53.8"} (1950)
GRB_ERROR:       4.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       6.93e-09 [erg/cm2/sec]
GRB_SIGNIF:      14.42 [sigma]
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63379.93 SOD {17:36:19.93} UT,   106.5 [sec] since BAT Trigger Time
TAM[0-3]:        327.63 237.24 261.32 243.36
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       325.71d {+21h 42m 50s}  -13.73d {-13d 43' 33"}
SUN_DIST:         88.71 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.72d {+02h 02m 54s}  +17.67d {+17d 40' 17"}
MOON_DIST:       160.08 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.22, 27.90 [deg] galactic lon,lat of the burst
ECL_COORDS:      234.55, -3.96 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.
COMMENTS:        The object found at this position is either a very bright burst or a cosmic ray hit.
COMMENTS:        Examine the XRT Image to differentiate (CRs are much more compact); see examples at:
COMMENTS:        http://www.swift.psu.edu/xrt/XRT_Postage_Stamp_Image_Photo_Gallery.htm .

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:37:01 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     303105,   Seg_Num: 0
GRB_RA:          231.1466d {+15h 24m 35.1s} (J2000),
                 231.2654d {+15h 25m 03.6s} (current),
                 230.4161d {+15h 21m 39.8s} (1950)
GRB_DEC:         -22.7410d {-22d 44' 27.5"} (J2000),
                 -22.7693d {-22d 46' 09.5"} (current),
                 -22.5650d {-22d 33' 53.8"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       208 [cnts]
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63379.93 SOD {17:36:19.93} UT,   106.5 [sec] since BAT Trigger Time
CENTROID_X:      269.10,  raw= 269  [pixels]
CENTROID_Y:      338.61,  raw= 339  [pixels]
ROLL:            104.43 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   95.73
GRB_POS_XRT_Z:   -78.24
IMAGE_URL:       sw00303105000msxps_rw.img
SUN_POSTN:       325.71d {+21h 42m 50s}  -13.73d {-13d 43' 33"}
SUN_DIST:         88.71 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.73d {+02h 02m 54s}  +17.67d {+17d 40' 19"}
MOON_DIST:       160.08 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.22, 27.90 [deg] galactic lon,lat of the burst
ECL_COORDS:      234.55, -3.96 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:37:06 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     303105,   Seg_Num: 0
GRB_RA:          231.1466d {+15h 24m 35.1s} (J2000),
                 231.2654d {+15h 25m 03.6s} (current),
                 230.4161d {+15h 21m 39.8s} (1950)
GRB_DEC:         -22.7410d {-22d 44' 27.5"} (J2000),
                 -22.7693d {-22d 46' 09.5"} (current),
                 -22.5650d {-22d 33' 53.8"} (1950)
GRB_ERROR:       4.7 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       208 [cnts]
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63379.93 SOD {17:36:19.93} UT,   106.5 [sec] since BAT Trigger Time
CENTROID_X:      269.10,  raw= 269  [pixels]
CENTROID_Y:      338.61,  raw= 339  [pixels]
ROLL:            104.43 [deg]
GAIN:            2
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   95.73
GRB_POS_XRT_Z:   -78.24
IMAGE_URL:       sw00303105000msxps_rw.img
SUN_POSTN:       325.71d {+21h 42m 50s}  -13.73d {-13d 43' 33"}
SUN_DIST:         88.71 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.73d {+02h 02m 54s}  +17.67d {+17d 40' 20"}
MOON_DIST:       160.08 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.22, 27.90 [deg] galactic lon,lat of the burst
ECL_COORDS:      234.55, -3.96 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN Circular #7294
E. Berger (Princeton) reports:
"Inspection of DSS and 2MASS images reveals an extended object coincident with the XRT position of GRB 080212 (trigger 303105). The coordinates are (J2000):
```
 	RA = 15:24:35.19
 	DEC= -22:44:29.0
```
This indicates that the burst is likely at low redshift."

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:50:54 UT
NOTICE_TYPE:     Swift-UVOT Source List
TRIGGER_NUM:     303105,   Seg_Num: 0
POINT_RA:        231.119d {+15h 24m 28s} (J2000)
POINT_DEC:       -22.758d {-22d 45' 29"} (J2000)
POINT_ROLL:      104.433d
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63382.69 SOD {17:36:22.69} UT,   109.2 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        4.566
N_STARS:         94
X_OFFSET:        526 [pixels]
Y_OFFSET:        325 [pixels]
X_MAX:           1485 [pixels]
Y_MAX:           1284 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    10
SL_URL:          sw00303105000msufc0109.fits
SUN_POSTN:       325.72d {+21h 42m 52s}  -13.72d {-13d 43' 21"}
SUN_DIST:         88.74 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.86d {+02h 03m 26s}  +17.72d {+17d 43' 24"}
MOON_DIST:       160.24 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.18, 27.91 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      234.53, -3.98 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Source List.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:51:25 UT
NOTICE_TYPE:     Swift-UVOT Processed Source List
TRIGGER_NUM:     303105,   Seg_Num: 0
POINT_RA:        231.119d {+15h 24m 28s} (J2000)
POINT_DEC:       -22.758d {-22d 45' 29"} (J2000)
POINT_ROLL:      104.433d
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63382.69 SOD {17:36:22.69} UT,   109.2 [sec] since BAT Trigger Time
FILTER:          3, V
BKG_MEAN:        4.566
N_STARS:         94
X_OFFSET:        526 [pixels]
Y_OFFSET:        325 [pixels]
X_MAX:           1485 [pixels]
Y_MAX:           1284 [pixels]
DET_THRESH:      18
PHOTO_THRESH:    10
SL_URL:          sw00303105000msufc0109.fits
SUN_POSTN:       325.72d {+21h 42m 52s}  -13.72d {-13d 43' 21"}
SUN_DIST:         88.74 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.86d {+02h 03m 27s}  +17.73d {+17d 43' 31"}
MOON_DIST:       160.25 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.18, 27.91 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      234.53, -3.98 [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 12 Feb 08 17:52:20 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     303105,   Seg_Num: 0
POINT_RA:        231.119d {+15h 24m 28s} (J2000)
POINT_DEC:       -22.758d {-22d 45' 29"} (J2000)
ROLL:            104.433d
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63382.69 SOD {17:36:22.69} UT,   109.2 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     224530585
X_OFFSET:        846 [pixels]
Y_OFFSET:        645 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1006
Y_GRB_POS:       805
BINNING_INDEX:   1
IM_URL:          sw00303105000msuni0109.fits
SUN_POSTN:       325.72d {+21h 42m 52s}  -13.72d {-13d 43' 20"}
SUN_DIST:         88.75 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.87d {+02h 03m 29s}  +17.73d {+17d 43' 43"}
MOON_DIST:       160.26 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.18, 27.91 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      234.53, -3.98 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Image.  
COMMENTS:        The GRB Position came from the XRT Position Command.  
COMMENTS:        The image has 2x2 binning (compression).

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Tue 12 Feb 08 17:52:43 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     303105,   Seg_Num: 0
POINT_RA:        231.119d {+15h 24m 28s} (J2000)
POINT_DEC:       -22.758d {-22d 45' 29"} (J2000)
ROLL:            104.433d
IMG_START_DATE:  14508 TJD;    43 DOY;   08/02/12
IMG_START_TIME:  63382.69 SOD {17:36:22.69} UT,   109.2 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     224530585
X_OFFSET:        846 [pixels]
Y_OFFSET:        645 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1006
Y_GRB_POS:       805
BINNING_INDEX:   1
IM_URL:          sw00303105000msuni0109.fits
SUN_POSTN:       325.72d {+21h 42m 53s}  -13.72d {-13d 43' 20"}
SUN_DIST:         88.75 [deg]   Sun_angle= 6.3 [hr] (West of Sun)
MOON_POSTN:       30.88d {+02h 03m 30s}  +17.73d {+17d 43' 48"}
MOON_DIST:       160.26 [deg]
MOON_ILLUM:      34 [%]
GAL_COORDS:      343.18, 27.91 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      234.53, -3.98 [deg] ecliptic lon,lat of the pointing direction
COMMENTS:        SWIFT-UVOT Processed Image.  
COMMENTS:        The GRB Position came from the XRT Position 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 #7296
H. Ziaeepour (UCL-MSSL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), A. P. Beardmore (U Leicester), P. J. Brown (PSU), D. N. Burrows (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC), G. Cusumano (INAF-IASFPA), M. De Pasquale (UCL-MSSL), O. Godet (U Leicester), C. Guidorzi (INAF-OAB), J. A. Kennea (PSU), H. A. Krimm (GSFC/USRA), V. Mangano (INAF-IASFPA), J. Mao (INAF-OAB), C. B. Markwardt (CRESST/GSFC/UMD), F. E. Marshall (NASA/GSFC), P. T. O'Brien (U Leicester), C. Pagani (PSU), K. L. Page (U Leicester), D. M. Palmer (LANL), D. Perez (U Leicester), P. Romano (INAF-IASFPA), T. Sakamoto (NASA/UMBC), G. Sato (GSFC/ISAS), B. Sbarufatti (INAF-IASFPA), M. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester), G. Tagliaferri (INAF-OAB), E. Troja (U Leicester/INAF-IASFPa), D. E. Vanden Berk (PSU) and L. Vetere (PSU) report on behalf of the Swift Team:
At 17:34:33 UT, the Swift Burst Alert Telescope (BAT) triggered and located GRB 080212 (trigger=303105). Swift slewed immediately to the burst. The BAT on-board calculated location is RA, Dec 231.107, -22.752 which is
```
   RA(J2000) = 15h 24m 26s
   Dec(J2000) = -22d 45' 06"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve showed a single peak with a duration of about 20 sec. The peak count rate was ~1000 counts/sec (15-350 keV), at ~0 sec after the trigger. There may be a precursor at T-60 sec.
The XRT began observing the field at 17:36:19 UT, 106 seconds after the BAT trigger. XRT found a bright, fading X-ray source located at RA, Dec 231.1466, -22.7410 which is
```
   RA(J2000)  =  15h 24m 35.1s
   Dec(J2000) = -22d 44' 27.5"
```
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This location is 137 arcseconds from the BAT on-board position, within the BAT error circle. The initial flux in the 2.5s image was 6.9e-09 erg/cm2/s (0.2-10 keV).
UVOT took a finding chart exposure of 400 seconds with the V filter starting 109 seconds after the BAT trigger. No afterglow candidate has been found in the initial data products. There is a object in the DSS image inside the XRT error circle which is also detected by UVOT with a magnitude of 17.7. The 2.7'x2.7' sub-image covers 100% of the XRT error circle. The 8'x8' region for the list of sources generated on-board covers 100% of the XRT error circle. No correction has been made for the expected extinction of about 0.5 magnitudes.
Burst Advocate for this burst is H. Ziaeepour (hz AT mssl.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 Circular #7299
K.L. Page, D. Perez (U Leicester) and H. Ziaeepour (UCL-MSSL) report on behalf of the Swift-XRT team:
We have analysed the first three orbits of data obtained for GRB 080212 (Ziaeepour et al., GCN Circ. 7296). Most of the initial orbit of data were collected in Windowed Timing (WT mode), and show strong flaring activity. Using the second two orbits [Photon Counting (PC) mode data; 5.2 ks of exposure time], we obtained a refined position of RA, Dec (J2000) = 231.1468, -22.7420, which is equivalent to
```
RA(J2000) =   15 24 35.24
Dec(J2000) = -22 44 31.0
```
with an estimated uncertainty of 3.6 arcsec. This is 3.7 arcsec from the onboard XRT position (GCN Circ. 7296).
Following the flares in the first orbit of data, the X-ray light-curve can be fitted with a power-law, with the decay slope, alpha = 0.8 +/- 0.1.
There is strong spectral evolution during the flaring WT data. A spectrum formed from the PC mode data can be modelled with an absorbed power-law, with Gamma = 2.3 +/- 0.2 and NH = (2.1 +/- 0.4)e21 cm^-2, significantly in excess of the Galactic value of 7.26e20 cm^-2. The 0.3-10 keV observed (unabsorbed) flux during this time (~3.5 - 12 ks after the trigger) is 8.4e-12 (1.5e-11) erg cm^-2 s^-1.
If the light-curve continues to decay at this rate, the predicted count rate at 24 hours will be 0.024 count s^-1. Using the PC data, a counts to flux conversion of 4.0e-11 erg cm^-2 count^-1 can be estimated, implying the predicted flux at 24 hours would be 9.6e-13 erg cm^-2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Circular #7300
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 080212, 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 = 231.14749, -22.74154 which is equivalent to:
```
RA (J2000): 15h 24m 35.40s
Dec (J2000): -22d 44' 29.5"
```
with an uncertainty of 2.0 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 #7301
A. S=E1nchez Caso (Gualba Obs., Barcelona), M. Jel=EDnek, A. J. Castro-Tirado, J. Gorosabel (IAA-CSIC, Granada) and D. P=E9rez-Ram=EDrez = (U. Leicester), on behalf of a larger collaboration, report:
"Following the detection of GRB 080212 by Swift/BAT (Ziaeepour et al., GCN Circ. 7296), we have obtained VRI-band images with the 0.4m Gualba Obs. telescope under non-optimal conditions, starting on Feb 13.263 UT (i.e. 13.0 hr after the trigger). At the Swift/XRT position given by Page et al. (GCN Circ. 7299) we only see the DSS2 galaxy pointed out by Berger (GCN Circ. 7294). The limiting magnitude of our images is R =3D 18. Much deeper optical/nIR observations are encouraged."
This message can be quoted.
GCN Circular #7302
P. D'Avanzo, L.A. Antonelli, S. Covino, D. Fugazza, L. Calzoletti, S. Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F. Dalessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel, N. Masetti, A. Melandri, E. Meurs, L. Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta, G. Tagliaferri, G. Tosti, V.Testa, S.D. Vergani, F. Vitali report on behalf of the REM team:
The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically the field of the GRB 080212 (Ziaeepour et al., GCN 7296). A preliminary analysis of the first set of H-band exposures does reveal the presence of an object with H ~ 15.2 inside the XRT error box (Goad et al., GCN 7300) at the following coordinates (J2000):
```
R.A. = 15:24:35.49
Dec. = -22:44:29.0
```
with an uncertainty of 0.3". This position lies about 3.2" (East direction) far from the position of the DSS galaxy (Berger, GCN 7294). This object could thus be the NIR afterglow of GRB 080212. The 3sigma upper limit of our image is H > 15.7 (calibrated against the 2MASS catalog).
Further analysis is in progress.
GCN Circular #7303
A. Kuepcue Yoldas, A. Yoldas, J. Greiner, T. Kruehler (all MPE Garching), A. Rossi (Tautenburg Obs) report for the GROND team:
We observed the field of GRB 080212 (trigger 303105) detected by Swift/BAT (Ziaeepour et al. 2008, GCN 7296) simultaneously in grizJHK with GROND (Greiner et al. 2008, astro-ph/0801.4801), mounted at the 2.2m MPI/ESO telescope at La Silla (Chile). Observations started on Feb. 13, at 05:30 UT (12 hrs after the GRB), when the GRB location was becoming visible at 20 degrees above horizon.
We detect a new source in all filters, suggesting the Ly-break being below the g'-band (and thus z<3.5). It is clearly separated from the galaxy mentioned by Berger et al. (2008, GCN 7294). The position is
```
  RA (2000.0) = 15:24:35.4 
  Decl (2000.0) = -22:44:30
```
At 6:36 UT we measure i'=22.6 mag. No statement about variability can be made at this stage. GROND observations are continuing.
GCN Circular #7304
E. Berger (Princeton) reports:
"A 900-sec spectrum obtained with Gemini-South/GMOS reveals that the object near the XRT position is a late-K star and not a galaxy as initially indicated in GCN 7294.
In a 60 sec r-band acquisition image we find a faint source coincident with the XRT position at:
```
 	RA = 15:24:35.4
 	DEC = -22:44:30	(J2000)
```
This object is consistent with the positions reoprted in GCNs 7302 and 7303."
GCN Circular #7305
M. Yoshida, K. Yanagisawa, Y. Shimizu, S. Nagayama (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf of the MITSuME collaboration:
We performed optical imaging observation (g', Rc, and Ic) of the field of GRB 080212 (Ziaeepour et al. GCN 7296) with 50cm MITSuME telescope at Okayama Astrophysical Observatory from UT 17:36:37 (124 sec after the trigger) to UT 20:30:38 on Feb 12 2008.
We found a 18 mag star in the vicinity of the XRT position (Goad et al. GCN 7300). This is the late-K star reported by Berger (GCN 7304). Although we could not spatially resolve the faint source close to this star reported by Berger (GCN7304), we found that a fading component is overlaid on the star. This component is a GRB afterglow candidate. We estimated the magnitudes of the fading component by subtracting the flux of the star at 2 hours after the trigger from the star magnitude at early time.
The estimated magnitudes of the fading component are summarized below.
Observation date 2008-02-12 UT
```
mid-UT    exp-T         g'           Rc           Ic
---------------------------------------------------------
17:42:47   10min   19.46+-0.26  17.77+-0.15  17.98+-0.22
18:00:27   22min   > 21.0       18.77+-0.14  18.91+-0.21
18:19:08   52min   > 21.0       19.88+-0.10  > 20.5
18:58:37  113min   > 21.0       > 20.5       > 20.5
---------------------------------------------------------
```
GCN Circular #7306
K. McLean (GSFC/UMD), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU), H. Ziaeepour (UCL-MSSL) (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 080212 (trigger #303105) (Ziaeepour, et al., GCN Circ. 7296). The BAT ground-calculated position is RA, Dec = 231.145, -22.739 deg, which is
```
   RA(J2000)  =  15h 24m 34.8s 
   Dec(J2000) = -22d 44' 19" 
```
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment). The partial coding was 35%.
The mask-weighted light curve shows the main burst acivity starting at about T-60 sec, the main peak at ~T+5 sec, and ending at about T+110 sec. There is a weak peak at T+250 to T+350 sec, which matches a flare in in the XRT lighcurve peaking at about T+250 sec. T90 (15-350 keV) is 123 +- 13 sec (estimated error including systematics).
The time-averaged spectrum from T-60.5 to T+75.7 sec is best fit by a power law with an exponential cutoff. This fit gives a photon index 0.31 +- 0.64, and Epeak of 67.6 +- 13.1 keV (chi squared 52.75 for 56 d.o.f.). For this model the total fluence in the 15-150 keV band is 2.9 +- 0.3 x 10^-06 erg/cm2 and the 1-sec peak flux measured from T+3.75 sec in the 15-150 keV band is 1.2 +- 0.3 ph/cm2/sec. A fit to a simple power law gives a photon index of 1.59 +- 0.12 (chi squared 68.06 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/303105/BA/
GCN Circular #7307
M. De Pasquale and H. Ziaeepour (MSSL/UCL) report on behalf of the Swift team:
The Swift/UVOT observed the field of GRB 080212 (trigger 303105) starting 110 seconds after the BAT trigger (Ziaeepour et al GCN Circ. 7296), which occurred at 17:34:33 UT. A source is detected in the enhanced XRT error circle reported by Evans et al (GCN circ. 7300), blended with the K-type star mentioned in GCN 7304 by Berger et al. The detection is only in the early V band exposures. There was no other 3-sigma detection of the afterglow in any exposure in any of the UVOT filters.
We do caution that photometry for this burst has been carried out in very difficult conditions. Furthermore, no correction has been made for the non-negligible Galactic extinction towards the burtst, which amounts to E(B-V) = 0.16
The detections and 3-sigma upper limits in the UVOT photometric system (Poole et al MNRAS 383, 627 (2008)) are summarized in the following table:
Filter Tstart(s) Tstop(s) Exp(s) Mag / Upper limit
V 110 510 393 17.8 +/- 0.1
V 4734 6166 393 19.3 +/- 0.3
V 21968 22876 893 >20.3
B 4323 4522 393 >20.7
B 11320 40999 1774 >21.2
U 4119 5548 393 >20.3
U 10408 40703 3400 >21.5
UW1 3919 5344 393 >20.0
UW1 9502 50920 4309 >21.2
UM2 3741 6300 323 >19.3
UM2 15290 45066 3413 >20.6
UW2 4529 5961 393 >19.4
UW2 21062 21961 893 >20.7
GCN Circular #7308
Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf of the Caltech-NRAO-Carnegie GRB Collaboration:
"We used the Very Large Array to observe the field of view toward GRB 080212 (GCN 7296) at a frequency of 8.46 GHz on 2008 February 13.53 UT. The radio afterglow of the GRB is undetected at the Swift-XRT position (GCN 7300) or optical afterglow position (GCN 7303). The peak flux density at the afterglow position is 83 +/- 51 uJy.
The National Radio Astronomy Observatory is a facility of the National Science Foundation operated under cooperative agreement by Associated Universities, Inc."
GCN Circular #7310
P. D'Avanzo, L.A. Antonelli, S. Covino, D. Fugazza, L. Calzoletti, S.=20 Campana, G. Chincarini, M.L. Conciatore, S. Cutini, V. D'Elia, F.=20 D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel,=20 E. Maiorano, D. Malesani, N. Masetti, A. Melandri, E.J.A. Meurs, L.=20 Nicastro, E. Palazzi, E. Pian, S. Piranomonte, L. Stella, G. Stratta,=20 G. Tagliaferri, G. Tosti, V. Testa, S.D. Vergani, F. Vitali report on=20 behalf of the REM team:
We performed a more careful analysis of the REM H-band images of GRB=20 080212 (Ziaeepour et al. GCN 7296). We confirm the afterglow detection=20 reported in D'Avanzo et al. (GCN 7302).The observations have been=20 carried out on Feb 13.2063 UT (about 11.4 hours after the burst) and=20 consist of three sets of images (lasting 10, 30 and 60 s respectively).
We confirm the presence of a H =3D 15.3 =B1 0.2 object (calibrated against the 2MASS catalogue) about 2.5" East of the K-type star (Berger, GCNs=20 7294 & 7304). The object is visible in both the 30 s and 60 s images at=20 the following coordinates (J2000):
```
R.A. =3D 15:24:35.42
Dec. =3D -22:44:28.8
```
with an uncertainty of 0.3" (the REM pixel size is 1.2"/pixel) .
When compared to the GROND optical detection (obtained about 1.7 hours=20 later, Kuepcue Yoldas et al. GCN 7303), our H-band measurement implies=20 a colour I-H ~ 7 mag, which is very red. A possible way out is to invoke=20 remarkable flaring activity around the time of the REM observation. We=20 note that the X-ray light curve (available at: http://www.swift.ac.uk/xrt_curves/00303105/) shows some evidence for rebrightening about 2 hr before the REM observation.
A finding chart, showing the detection at different H-band images can be found at the following URL:
http://www.brera.inaf.it/utenti/davanzo/public/grb/GRB080212/GRB080212_REMIR_FC.jpg
GCN Circular #7311
P. D'Avanzo, D. Fugazza (INAF-OAB), L.A. Antonelli (INAF-OAR), S. Covino, G. Chincarini, C. Guidorzi, G. Tagliaferri (INAF-OAB), V. D'Elia, F. Fiore, S. Piranomonte, L. Stella (INAF-OAR), M. Della Valle (INAF-OAA), S. D. Vergani (DIAS-DCU) report on behalf of the MISTICI collaboration:
We observed the optical afterglow of GRB 080212 (Ziaeepour et al., GCN 7296) with the ESO-VLT equipped with the FORS2 camera in imaging mode at three different epochs. Observations have been carried out in R-band on Feb 13.3101 UT, Feb 13.3682 UT and Feb 14.2838 UT (0.58, 0.64 and 1.55 days after the burst, respectively).
We found that between the first two epochs the afterglow faded very rapidly, with a decay index of alpha ~ 5.5. Very likely, the afterglow underwent a remarkable increase of its optical/NIR flux, probably related to the brightening observed in the X-rays about 4 hours before our VLT observations (see D'Avanzo et al., GCN 7310).
Assuming the above decay index, we estimate R ~ 20.8 at the epoch of the REM detection (D'Avanzo et al., GCN 7302) with an implied colour R-H~5
The decay of the afterglow then slowed down between the last two epochs and we measure R~25 in our last observation.
GCN Circular #7321
Lokesh, V. Venkat, J. Jain, S. Vadawale and B.G. Anandarao Physical Research Laboratory, Ahmedabad, India.
We made infrared photometry in J band at Mt. Abu 1.2 m Cassegrain telescope using NICMOS camera on the GRB 080212 (Ziaeepour et al. GCN 7296) during 2008 Feb 13 under good sky conditions. The H band magnitude was earlier reported by P. D'Avanzo et. al (GCN 7310). The calibration was made on the bright star SAO 183333. The overall integration time and the magnitude along with the associated error are given below:
```
UT           Integration time	J band magnitude+/-error
13.97		1080s		16.8+/-0.1
```
GCN Report 115.1
GCN_Report 115.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_115_1.pdf by H. Ziaeepour at UCL/MSSL titled: "Final Swift observations of GRB 080212"

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Jochen Greiner, last update: 20-Feb-2008 [Disclaimer]