Gamma-ray Burst 070126

(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:     Fri 26 Jan 07 02:34:42 UT
NOTICE_TYPE:     Swift-BAT GRB Position
TRIGGER_NUM:     257741,   Seg_Num: 0
GRB_RA:           33.460d {+02h 13m 50s} (J2000),
                  33.478d {+02h 13m 55s} (current),
                  33.342d {+02h 13m 22s} (1950)
GRB_DEC:         -73.523d {-73d 31' 23"} (J2000),
                 -73.490d {-73d 29' 25"} (current),
                 -73.756d {-73d 45' 20"} (1950)
GRB_ERROR:       3.00 [arcmin radius, statistical only]
GRB_INTEN:       0 [cnts]    Image_Peak=1367 [image_cnts]
TRIGGER_DUR:     64.000 [sec] 
TRIGGER_INDEX:   20000     E_range: 15-50 keV
BKG_INTEN:       0 [cnts]
BKG_TIME:        0.00 SOD {00:00:00.00} UT
BKG_DUR:         0 [sec]
GRB_DATE:        14126 TJD;    26 DOY;   07/01/26
GRB_TIME:        9206.27 SOD {02:33:26.27} UT
GRB_PHI:          91.75 [deg]
GRB_THETA:         6.05 [deg]
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.04 [sigma]
MERIT_PARAMS:     +1  +0  +0  +6  +1  -3  +0  +0 -33  +1 
SUN_POSTN:       308.11d {+20h 32m 28s}  -18.83d {-18d 50' 02"}
SUN_DIST:         70.65 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.91d {+02h 15m 39s}  +17.82d {+17d 49' 26"}
MOON_DIST:        91.31 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.17,-42.34 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      314.84,-70.39 [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 = 262.70,-3.90 [deg].

red DSS finding chart ps-file

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Jan 07 02:36:00 UT
NOTICE_TYPE:     Swift-XRT Processed Image
TRIGGER_NUM:     257741,   Seg_Num: 0
GRB_RA:           33.1270d {+02h 12m 30.4s} (J2000),
                  33.1448d {+02h 12m 34.7s} (current),
                  33.0047d {+02h 12m 01.1s} (1950)
GRB_DEC:         -73.5476d {-73d 32' 51.3"} (J2000),
                 -73.5146d {-73d 30' 52.7"} (current),
                 -73.7809d {-73d 46' 51.3"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       68 [cnts]
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9321.86 SOD {02:35:21.86} UT,   115.6 [sec] since BAT Trigger Time
CENTROID_X:      162.89,  raw= 163  [pixels]
CENTROID_Y:      339.62,  raw= 340  [pixels]
ROLL:            268.91 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   98.11
GRB_POS_XRT_Z:   -328.62
IMAGE_URL:       sw00257741000msxps_rw.img
SUN_POSTN:       308.12d {+20h 32m 28s}  -18.83d {-18d 50' 01"}
SUN_DIST:         70.56 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.92d {+02h 15m 42s}  +17.83d {+17d 49' 43"}
MOON_DIST:        91.34 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.30,-42.36 [deg] galactic lon,lat of the burst
ECL_COORDS:      314.72,-70.30 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Processed Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Jan 07 02:35:56 UT
NOTICE_TYPE:     Swift-XRT Image
TRIGGER_NUM:     257741,   Seg_Num: 0
GRB_RA:           33.1270d {+02h 12m 30.4s} (J2000),
                  33.1448d {+02h 12m 34.7s} (current),
                  33.0047d {+02h 12m 01.1s} (1950)
GRB_DEC:         -73.5476d {-73d 32' 51.3"} (J2000),
                 -73.5146d {-73d 30' 52.7"} (current),
                 -73.7809d {-73d 46' 51.3"} (1950)
GRB_ERROR:       5.0 [arcsec, radius, statistical plus systematic]
GRB_INTEN:       68 [cnts]
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9321.86 SOD {02:35:21.86} UT,   115.6 [sec] since BAT Trigger Time
CENTROID_X:      162.89,  raw= 163  [pixels]
CENTROID_Y:      339.62,  raw= 340  [pixels]
ROLL:            268.91 [deg]
GAIN:            1
MODE:            3, Long Image mode
WAVEFORM:        134
EXPO_TIME:       2.50 [sec]
GRB_POS_XRT_Y:   98.11
GRB_POS_XRT_Z:   -328.62
IMAGE_URL:       sw00257741000msxps_rw.img
SUN_POSTN:       308.12d {+20h 32m 28s}  -18.83d {-18d 50' 01"}
SUN_DIST:         70.56 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.92d {+02h 15m 42s}  +17.83d {+17d 49' 42"}
MOON_DIST:        91.34 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.30,-42.36 [deg] galactic lon,lat of the burst
ECL_COORDS:      314.72,-70.30 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Image.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Jan 07 02:35:56 UT
NOTICE_TYPE:     Swift-XRT Position
TRIGGER_NUM:     257741,   Seg_Num: 0
GRB_RA:           33.1270d {+02h 12m 30.4s} (J2000),
                  33.1448d {+02h 12m 34.7s} (current),
                  33.0047d {+02h 12m 01.1s} (1950)
GRB_DEC:         -73.5476d {-73d 32' 51.3"} (J2000),
                 -73.5146d {-73d 30' 52.7"} (current),
                 -73.7809d {-73d 46' 51.3"} (1950)
GRB_ERROR:       5.0 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN:       2.29e-09 [erg/cm2/sec]
GRB_SIGNIF:      8.24 [sigma]
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9321.86 SOD {02:35:21.86} UT,   115.6 [sec] since BAT Trigger Time
TAM[0-3]:        327.59 237.20 261.45 243.11
AMPLIFIER:       2
WAVEFORM:        134
SUN_POSTN:       308.12d {+20h 32m 28s}  -18.83d {-18d 50' 01"}
SUN_DIST:         70.56 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.92d {+02h 15m 42s}  +17.83d {+17d 49' 42"}
MOON_DIST:        91.34 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.30,-42.36 [deg] galactic lon,lat of the burst
ECL_COORDS:      314.72,-70.30 [deg] ecliptic lon,lat of the burst
COMMENTS:        SWIFT-XRT Coordinates.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Jan 07 02:37:30 UT
NOTICE_TYPE:     Swift-BAT GRB Lightcurve
TRIGGER_NUM:     257741,   Seg_Num: 0
GRB_RA:           33.460d {+02h 13m 50s} (J2000),
                  33.478d {+02h 13m 55s} (current),
                  33.342d {+02h 13m 22s} (1950)
GRB_DEC:         -73.523d {-73d 31' 23"} (J2000),
                 -73.490d {-73d 29' 25"} (current),
                 -73.756d {-73d 45' 20"} (1950)
GRB_DATE:        14126 TJD;    26 DOY;   07/01/26
GRB_TIME:        9206.27 SOD {02:33:26.27} UT
TRIGGER_INDEX:   20000
GRB_PHI:          91.75 [deg]
GRB_THETA:         6.05 [deg]
DELTA_TIME:      0.00 [sec]
TRIGGER_DUR:     64.000 [sec] 
SOLN_STATUS:     0x13
RATE_SIGNIF:     0.00 [sigma]
IMAGE_SIGNIF:    7.04 [sigma]
LC_URL:          sw00257741000msb.lc
SUN_POSTN:       308.12d {+20h 32m 28s}  -18.83d {-18d 50' 00"}
SUN_DIST:         70.65 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.94d {+02h 15m 45s}  +17.83d {+17d 50' 04"}
MOON_DIST:        91.33 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.17,-42.34 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS:      314.84,-70.39 [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 = 262.70,-3.90 [deg].

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Jan 07 02:38:37 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     257741,   Seg_Num: 0
POINT_RA:         33.447d {+02h 13m 47s} (J2000)
POINT_DEC:       -73.519d {-73d 31' 07"} (J2000)
ROLL:            268.912d
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9329.06 SOD {02:35:29.06} UT,   122.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     191471730
X_OFFSET:        1269 [pixels]
Y_OFFSET:        393 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1429
Y_GRB_POS:       553
BINNING_INDEX:   1
IM_URL:          sw00257741000msuni0122.fits
SUN_POSTN:       308.12d {+20h 32m 28s}  -18.83d {-18d 50' 00"}
SUN_DIST:         70.65 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.95d {+02h 15m 48s}  +17.84d {+17d 50' 19"}
MOON_DIST:        91.33 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.17,-42.35 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      314.85,-70.39 [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:     Fri 26 Jan 07 02:38:50 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     257741,   Seg_Num: 0
POINT_RA:         33.447d {+02h 13m 47s} (J2000)
POINT_DEC:       -73.519d {-73d 31' 07"} (J2000)
ROLL:            268.912d
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9329.06 SOD {02:35:29.06} UT,   122.8 [sec] since BAT Trigger Time
FILTER:          10, White
EXPOSURE_ID:     191471730
X_OFFSET:        1269 [pixels]
Y_OFFSET:        393 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1429
Y_GRB_POS:       553
BINNING_INDEX:   1
IM_URL:          sw00257741000msuni0122.fits
SUN_POSTN:       308.12d {+20h 32m 28s}  -18.83d {-18d 50' 00"}
SUN_DIST:         70.65 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.95d {+02h 15m 48s}  +17.84d {+17d 50' 22"}
MOON_DIST:        91.33 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.17,-42.35 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      314.85,-70.39 [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_catalog_image.fits.gz file does not exist; skipping the attachment.

GCN NOTICE

TITLE:           GCN/SWIFT NOTICE
NOTICE_DATE:     Fri 26 Jan 07 02:42:16 UT
NOTICE_TYPE:     Swift-UVOT Image
TRIGGER_NUM:     257741,   Seg_Num: 0
POINT_RA:         33.441d {+02h 13m 46s} (J2000)
POINT_DEC:       -73.519d {-73d 31' 08"} (J2000)
ROLL:            268.916d
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9434.27 SOD {02:37:14.27} UT,   228.0 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     191471835
X_OFFSET:        1269 [pixels]
Y_OFFSET:        393 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1429
Y_GRB_POS:       553
BINNING_INDEX:   1
IM_URL:          sw00257741000msuni0227.fits
SUN_POSTN:       308.12d {+20h 32m 29s}  -18.83d {-18d 49' 57"}
SUN_DIST:         70.65 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.98d {+02h 15m 56s}  +17.85d {+17d 51' 08"}
MOON_DIST:        91.34 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.18,-42.35 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      314.85,-70.39 [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:     Fri 26 Jan 07 02:42:32 UT
NOTICE_TYPE:     Swift-UVOT Processed Image
TRIGGER_NUM:     257741,   Seg_Num: 0
POINT_RA:         33.441d {+02h 13m 46s} (J2000)
POINT_DEC:       -73.519d {-73d 31' 08"} (J2000)
ROLL:            268.916d
IMG_START_DATE:  14126 TJD;    26 DOY;   07/01/26
IMG_START_TIME:  9434.27 SOD {02:37:14.27} UT,   228.0 [sec] since BAT Trigger Time
FILTER:          3, V
EXPOSURE_ID:     191471835
X_OFFSET:        1269 [pixels]
Y_OFFSET:        393 [pixels]
WIDTH:           160 [pixels]
HEIGHT:          160 [pixels]
X_GRB_POS:       1429
Y_GRB_POS:       553
BINNING_INDEX:   1
IM_URL:          sw00257741000msuni0227.fits
SUN_POSTN:       308.12d {+20h 32m 29s}  -18.83d {-18d 49' 57"}
SUN_DIST:         70.65 [deg]   Sun_angle= -5.7 [hr] (East of Sun)
MOON_POSTN:       33.99d {+02h 15m 56s}  +17.85d {+17d 51' 12"}
MOON_DIST:        91.34 [deg]
MOON_ILLUM:      52 [%]
GAL_COORDS:      295.18,-42.35 [deg] galactic lon,lat of the pointing direction
ECL_COORDS:      314.85,-70.39 [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:        All 4 attachments are included.

GCN Circular #6027
L. Vetere (PSU), M. M. Chester (PSU), J. R. Cummings (NASA/UMBC), S. T. Holland (CRESST/GSFC/USRA), S. Immler (GSFC/USRA), C. B. Markwardt (GSFC/UMD), F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), J. L. Racusin (PSU), J. L. Racusin (PSU), M. Stamatikos (NASA/ORAU), R. L. C. Starling (U Leicester) and E. Troja (INAF-IASFPA) report on behalf of the Swift Team:
At 02:33:26 UT, the Swift Burst Alert Telescope (BAT) triggered and located a possible source (trigger=257741). Swift slewed immediately to the location. The BAT on-board calculated location is RA, Dec 33.460, -73.523 which is
```
   RA(J2000) = 02h 13m 50s
   Dec(J2000) = -73d 31' 23"
```
with an uncertainty of 3 arcmin (radius, 90% containment, including systematic uncertainty). The BAT light curve shows no significant variation, which is not uncommon for image triggers. We will have to wait for ground analysis to determine if this is a real source.
The XRT began observing the field at 02:35:21 UT, 116 seconds after the BAT trigger. XRT centroided on a cosmic ray and no source is visible in the field of view up to an exposure time of 203s.
The UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm) filter starting 123 seconds after the BAT trigger. The quickly available image does not cover any portion of the BAT error circle.
GCN Circular #6037
S. Immler (NASA/USRA) and L. Vetere (PSU) report on the behalf of the Swift UVOT team:
The Swift/UVOT began observing the field of the possible burst GRB 070126 123 seconds after the BAT trigger (Vetere et al., GCN 6027). No optical afterglow candidate is detected in the BAT error circle within the first 100 s White exposure or in a coadded 590 s image, down to a limiting magnitude of 21.0 (3-sigma). The other UVOT filters only cover a small fraction (around 25%) of the BAT error circle.
No correction has been made for the expected extinction corresponding to E(B-V) = 0.05 mag (Schlegel et al. 1998).
GCN Circular #6040
E. Fenimore (LANL), L. Barbier (GSFC), S. D. Barthelmy (GSFC), J. Cummings (GSFC/UMBC), N. Gehrels (GSFC), 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), L. Vetere (PSU) on behalf of the Swift-BAT team:
Using the data set from T-240 to T+500 sec from the recent telemetry downlink, we report further analysis of BAT GRB 070126 (trigger #257741) (Veter, et al., GCN Circ. 6027). The BAT ground-calculated position is RA, Dec = 33.579, -73.532 deg which is
```
   RA(J2000)  =   2h 14m 18.9s 
   Dec(J2000) = -73d 31' 54" 
```
with an uncertainty of 2.7 arcmin, (radius, sys+stat, 90% containment). The partial coding was 99%.
The mask-weighted lightcurve shows a broad, weak, and soft bump from T_zero to ~T+60 sec. T90 (15-350 keV) is 51 +- 5 sec (estimated error including systematics).
The time-averaged spectrum from T+1.0 to T+56.0 is best fit by a simple power-law model. The power law index of the time-averaged spectrum is 1.9 +- 0.5. The fluence in the 15-150 keV band is 1.6 +- 0.6 x 10^-7 erg/cm2. The 1-sec peak photon flux measured from T+10.00 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 flux of this burst is at the lower limit of the BAT sensitivity.
GCN Circular #6045
L. Vetere, J. Racusin (PSU) reports on behalf of Swift XRT Team:
We analysed the first 28ks of XRT data of the faint burst GRB 070126 (Vetere et al., GCN 6027). We do find in the BAT error circle (Fenimore et al., GCN 6040) a detection of a faint uncatalogued X-ray source at the following coordinates:
```
  RA(J2000)  =  2h 14m 09.78s
  Dec(J2000) = -73d 32' 06.7"
```
with an estimated uncertainty of 4.4 arcseconds (90% containment). This position lies 0.7 arcmin from the BAT refined position reported by Fenimore et al. (GCN 6040).
The PSF corrected count rate is (7.1 +/- 2.3)e-4 cts/s. No other point source is detected above the 3 sigma upper limit of 1.0e-3 cts/s inside BAT error circle.
Due to the small number of counts, we are unable to determine whether the source is decaying at this time. Observations are continuing and further analysis regarding the fading nature of this source will be issued as the data become available.
This circular is an official product of the Swift XRT Team.
GCN Circular #6046
D. Malesani (Dark/NBI), P.M. Vreeswijk (ESO), P. Jakobsson (Herfordshire), J.P.U. Fynbo (Dark/NBI), report on behalf of a larger collaboration:
We observed the field of the faint GRB 070126 (Vetere et al., GCN 6027) with the ESO VLT + FORS2 on 2006 Jan 26.17 UT (1.52 hr after the GRB). Short exposures (~1 min) were acquired in BVRIz. Inside the XRT error circle (Vetere \& Racusin, GCN 6045) we detect a single, extended source, which is present in the USNO-B1 catalog and in the DSS images, at the coordinates (0.5" error):
```
RA(J2000) = 02:14:10.03
Dec(J2000) = -73:32:05.7
```
Given the lack of evidence for variability of the X-ray source, the possible association of this galaxy with the GRB or the X-ray source is at present unclear.
Our images cover ~80% of the refined BAT error circle (Fenimore et al., GCN 6040). No new sources brighter than the DSS limits (R~20.5) are seen across the whole observed region.
We acknowledge excellent support from the ESO staff at Paranal, in particular Hugues Sana, Thomas Rivinius, Leonardo Vanzi and Dominique Naef.
GCN Report 29.1
GCN_Report 29.1 has been posted: http://gcn.gsfc.nasa.gov/reports/report_29_1.pdf by L. Vetere at PSU titled: "Swift Observations of GRB 070126"
GCN Circular #6052
S. Immler (NASA/USRA) and L. Vetere (PSU) report on the behalf of the Swift UVOT team:
An extended source is found at the position reported by Malesani et al. (GCN 6046) in UVOT images of GRB 070126, consistent with the position of the XRT source (Vetere & Racusin, GCN 6045). The source is also present in DSS images and could be the host galaxy of the faint burst.
The table below gives the measured UVOT magnitudes. The position of the burst is outside the UVOT field-of-view for all other filters.
```
Filter  T_start    T_end    Exposure Mag    Error
WHITE   123      6146    590         21.8   0.4
UVW1    3900    40895    3592     21.0    0.3
UVM2    5128    40337    3333     21.5    0.3
UVW2    4719     6214    2588     >20.4  (3-sigma UL)
```
T_start and T_end are the start and stop times of the summed exposures in seconds from the trigger. No correction has been made for the expected extinction corresponding to E(B-V) = 0.05 mag (Schlegel et al. 1998).
GCN Circular #6068
L. Vetere, J. Racusin, D.N. Burrows, C. Pagani (PSU) report on behalf of Swift XRT Team:
We have re-observed the field of GRB 070126 (Vetere et al., GCN 6027) from 2007-01-30 00:49:07.62 (~340ks after BAT trigger) to 2007-02-01 14:10:17.0 for a total exposure of ~27.2ks.
The possible afterglow candidate that we reported in GCN 6045 is still present and shows a slightly increased count rate (1.4 +/- 0.3)E-03 cts/sec compared to (0.76 +/- 0.23) E-03 cts/sec obtained with the first 28ks of observation. We thus conclude that the object reported is not the X-ray afterglow of GRB 070126.
No other point sources are detected above the 3 sigma upper limit of 1.0e-3 cts/s inside BAT error circle.
This circular is an official product of the Swift XRT Team.

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Jochen Greiner, last update: 02-Feb-2007 [Disclaimer]