- GCN/BACODINE POSITION NOTICE
TITLE: GCN/SWIFT NOTICE
NOTICE_DATE: Sun 17 Dec 06 03:40:20 UT
NOTICE_TYPE: Swift-BAT GRB Position
TRIGGER_NUM: 251634, Seg_Num: 0
GRB_RA: 160.442d {+10h 41m 46s} (J2000),
160.526d {+10h 42m 06s} (current),
159.837d {+10h 39m 21s} (1950)
GRB_DEC: -21.118d {-21d 07' 05"} (J2000),
-21.155d {-21d 09' 16"} (current),
-20.856d {-20d 51' 22"} (1950)
GRB_ERROR: 3.00 [arcmin radius, statistical only]
GRB_INTEN: 1385 [cnts] Image_Peak=116 [image_cnts]
TRIGGER_DUR: 0.256 [sec]
TRIGGER_INDEX: 126 E_range: 50-350 keV
BKG_INTEN: 24185 [cnts]
BKG_TIME: 13198.36 SOD {03:39:58.36} UT
BKG_DUR: 8 [sec]
GRB_DATE: 14086 TJD; 351 DOY; 06/12/17
GRB_TIME: 13208.21 SOD {03:40:08.21} UT
GRB_PHI: -93.88 [deg]
GRB_THETA: 14.89 [deg]
SOLN_STATUS: 0x3
RATE_SIGNIF: 21.63 [sigma]
IMAGE_SIGNIF: 8.27 [sigma]
MERIT_PARAMS: +1 +0 +0 -2 +3 +7 +0 +0 +6 +1
SUN_POSTN: 264.61d {+17h 38m 26s} -23.35d {-23d 20' 42"}
SUN_DIST: 93.75 [deg] Sun_angle= 6.9 [hr] (West of Sun)
MOON_POSTN: 220.92d {+14h 43m 40s} -20.06d {-20d 03' 41"}
MOON_DIST: 56.18 [deg]
MOON_ILLUM: 12 [%]
GAL_COORDS: 266.59, 32.45 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 170.75,-27.05 [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 = 3.69,9.60 [deg].
- red DSS finding chart
ps-file
- GCN NOTICE
TITLE: GCN/SWIFT NOTICE
NOTICE_DATE: Sun 17 Dec 06 03:41:20 UT
NOTICE_TYPE: Swift-XRT Nack-Position
TRIGGER_NUM: 251634, Seg_Num: 0
POINT_RA: 160.436d {+10h 41m 45s} (J2000)
POINT_DEC: -21.106d {-21d 06' 22"} (J2000)
IMG_START_DATE: 14086 TJD; 351 DOY; 06/12/17
IMG_START_TIME: 13272.44 SOD {03:41:12.44} UT, 64.2 [sec] since BAT Trigger Time
COUNTS: 2 Min_needed= 20
STD_DEV: 0.00 Max_StdDev_for_Good=28.44 [arcsec]
PH2_ITER: 1 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: Sun 17 Dec 06 03:46:33 UT
NOTICE_TYPE: Swift-BAT GRB Lightcurve
TRIGGER_NUM: 2768131, Seg_Num: 67
GRB_RA: 160.442d {+10h 41m 46s} (J2000),
160.526d {+10h 42m 06s} (current),
159.837d {+10h 39m 21s} (1950)
GRB_DEC: -21.118d {-21d 07' 05"} (J2000),
-21.155d {-21d 09' 16"} (current),
-20.856d {-20d 51' 22"} (1950)
GRB_DATE: 14086 TJD; 351 DOY; 06/12/17
GRB_TIME: 13208.21 SOD {03:40:08.21} UT
TRIGGER_INDEX: 126
GRB_PHI: -93.88 [deg]
GRB_THETA: 14.89 [deg]
DELTA_TIME: 3378.00 [sec]
TRIGGER_DUR: 0.256 [sec]
SOLN_STATUS: 0x3
RATE_SIGNIF: 21.63 [sigma]
IMAGE_SIGNIF: 8.27 [sigma]
LC_URL: sw00251634000msb.lc
SUN_POSTN: 264.61d {+17h 38m 27s} -23.35d {-23d 20' 43"}
SUN_DIST: 93.75 [deg] Sun_angle= 6.9 [hr] (West of Sun)
MOON_POSTN: 220.97d {+14h 43m 53s} -20.08d {-20d 04' 48"}
MOON_DIST: 56.22 [deg]
MOON_ILLUM: 12 [%]
GAL_COORDS: 266.59, 32.45 [deg] galactic lon,lat of the burst (or transient)
ECL_COORDS: 170.75,-27.05 [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 = 3.69,9.60 [deg].
COMMENTS: The 3rd packet (of 3) was missing in the lightcurve data stream.
- GCN Circular #5926
S. D. Barthelmy (GSFC), D. N. Burrows (PSU), M. M. Chester (PSU),
J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester),
N. Gehrels (NASA/GSFC), O. Godet (U Leicester),
C. B. Markwardt (GSFC/UMD), F. E. Marshall (NASA/GSFC),
K. L. Page (U Leicester), D. M. Palmer (LANL),
M. Stamatikos (NASA/ORAU) and R. L. C. Starling (U Leicester) report
on behalf of the Swift Team:
At 03:40:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 061217 (trigger=251634). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 160.442, -21.118 which is
RA(J2000) = 10h 41m 46s
Dec(J2000) = -21d 07' 05"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows a single spike
of approximately 400 msec duration. The peak count rate
was ~4500 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began taking data at 03:41:12 UT, 64 seconds after the BAT
trigger. The XRT on-board centroid algorithm did not find a source in
the image and no source is detected in 17 s of promptly available
photon counting mode data. We are waiting for down-linked data to
detect and determine a position for the source.
Initial data products were not received from the UVOT because it was
not in its normal observing configuration at the time of the BAT
trigger. The UVOT returned to its normal configuration at 03:46:15.
Data are expected in approximately 2.5 hours.
- GCN Circular #5927
B. E. Schaefer (Louisiana State) reports on behalf of the ROTSE
collaboration:
ROTSE-IIId, located at the Turkish National Observatory at Bakirlitepe,
Turkey, responded to GRB 061217 (Swift trigger 251634), producing images
beginning 6.3 s after the GCN notice time. An automated response took the
first image at 03:40:26.3 UT, 18.1 s after the burst, under excellent
conditions. We took 10 5-sec, 10 20-sec and 20 60-sec eposures. These
unfiltered images are calibrated relative to USNO A2.0 (R). The last few
images have substantial background from twilight, and so our imaging has
now stopped in Turkey.
Comparison to the DSS (second epoch) reveals no new sources within the
3-sigma error circle, for both single images and coadding into sets of 10;
the field is not crowded. Individual images have limiting magnitudes
ranging from 15.3-16.9; we set the following specific limits.
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd?
--------------------------------------------------------------------
03:40:26.3 03:40:31.3 5 15.3 18.1 N
03:40:26.3 03:42:34.5 128 17.2 18.1 Y
03:58:53.0 04:10:09.5 676 17.3 1124.8 Y
- GCN NOTICE
TITLE: GCN/SWIFT NOTICE
NOTICE_DATE: Sun 17 Dec 06 05:04:08 UT
NOTICE_TYPE: Swift-UVOT Source List
TRIGGER_NUM: 251634, Seg_Num: 0
POINT_RA: 160.420d {+10h 41m 41s} (J2000)
POINT_DEC: -21.118d {-21d 07' 02"} (J2000)
POINT_ROLL: 116.855d
IMG_START_DATE: 14086 TJD; 351 DOY; 06/12/17
IMG_START_TIME: 18125.24 SOD {05:02:05.24} UT, 4917.0 [sec] since BAT Trigger Time
FILTER: 10, White
BKG_MEAN: 1.487
N_STARS: 55
X_OFFSET: 583 [pixels]
Y_OFFSET: 443 [pixels]
X_MAX: 1542 [pixels]
Y_MAX: 1402 [pixels]
DET_THRESH: 10
PHOTO_THRESH: 5
SL_URL: sw00251634000msufc4917.fits
SUN_POSTN: 264.67d {+17h 38m 41s} -23.35d {-23d 20' 50"}
SUN_DIST: 93.82 [deg] Sun_angle= 7.0 [hr] (West of Sun)
MOON_POSTN: 221.63d {+14h 46m 32s} -20.31d {-20d 18' 39"}
MOON_DIST: 56.80 [deg]
MOON_ILLUM: 12 [%]
GAL_COORDS: 266.57, 32.44 [deg] galactic lon,lat of the pointing direction
ECL_COORDS: 170.73,-27.06 [deg] ecliptic lon,lat of the pointing direction
COMMENTS: SWIFT-UVOT Source List.
- GCN NOTICE
TITLE: GCN/SWIFT NOTICE
NOTICE_DATE: Sun 17 Dec 06 05:05:20 UT
NOTICE_TYPE: Swift-UVOT Image
TRIGGER_NUM: 251634, Seg_Num: 0
POINT_RA: 160.420d {+10h 41m 41s} (J2000)
POINT_DEC: -21.118d {-21d 07' 02"} (J2000)
ROLL: 116.855d
IMG_START_DATE: 14086 TJD; 351 DOY; 06/12/17
IMG_START_TIME: 18125.24 SOD {05:02:05.24} UT, 4917.0 [sec] since BAT Trigger Time
FILTER: 10, White
EXPOSURE_ID: 188024526
X_OFFSET: 902 [pixels]
Y_OFFSET: 762 [pixels]
WIDTH: 160 [pixels]
HEIGHT: 160 [pixels]
X_GRB_POS: 1062
Y_GRB_POS: 922
BINNING_INDEX: 1
IM_URL: sw00251634000msuni4917.fits
SUN_POSTN: 264.67d {+17h 38m 41s} -23.35d {-23d 20' 50"}
SUN_DIST: 93.82 [deg] Sun_angle= 7.0 [hr] (West of Sun)
MOON_POSTN: 221.64d {+14h 46m 34s} -20.31d {-20d 18' 51"}
MOON_DIST: 56.81 [deg]
MOON_ILLUM: 12 [%]
GAL_COORDS: 266.57, 32.44 [deg] galactic lon,lat of the pointing direction
ECL_COORDS: 170.73,-27.06 [deg] ecliptic lon,lat of the pointing direction
COMMENTS: SWIFT-UVOT Image.
COMMENTS: The GRB Position came from the Window Position in the Mode Command.
COMMENTS: The image has 2x2 binning (compression).
- GCN Circular #5928
P. D'Avanzo, S. Covino, E. Molinari, G. Chincarini, F.M. Zerbi, V.
Testa, G. Tosti, F. Vitali, P. Conconi, L.A. Antonelli, G. Cutispoto,
G. Malaspina, L. Nicastro, E. Palazzi, E. Meurs, and P. Goldoni report
on behalf of the REM/ROSS team
We observed the field of GRB 061217 (Barthelmy et al. GCN 5926) with
the robotic 60-cm REM telescope located at La Silla (Chile). A set of
observations was performed automatically in the optical and near
infrared filters (V, R, I and J, H, K, z) starting on 2006 December 17
at 03:40:56 UT, 35 s after the BAT trigger and 48 s after the GRB time.
Preliminary analysis of the whole dataset does not show any new
variable source inside the BAT error box.
The 3-sigma limiting magnitudes are:
R~18.0
J~16.0
H~15.0
K~13.5
This message may be cited.
- GCN Circular #5929
E. Berger (Carnegie), A. Romanowsky (Concepcion), and C. Vega (Catolica)
report:
"We observed the error circle of GRB 061217 (GCN #5926) with IMACS on the
Magellan 6.5-m telescope for a total of 600 sec in R-band starting on 2006
Dec. 17.27 UT. A comparison to DSS reveals no new object to the limit of
the Sky Survey. We note the presence of a compact galaxy group at:
RA = 10:41:50.835
DEC= -21:05:16.68 (J2000)
This group is also apparent in the DSS images of this field. Given past
associations of short GRBs with galaxy groups and clusters, this galaxy
group may be the host of the short GRB. Further observations are
planned."
- GCN Circular #5930
A. Parsons (GSFC), L. Barbier (GSFC), 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),
T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS), M. Stamatikos (GSFC/ORAU),
J. Tueller (GSFC), H. Ziaeepour (MSSL)
on behalf of the Swift-BAT team:
Using the a limited data set from T-10 to T+57 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 061217 (trigger #251634)
(Barthelmy, et al., GCN Circ. 5926). The BAT ground-calculated position
is RA, Dec = 160.418, -21.148 deg which is
RA(J2000) = 10h 41m 40.4s
Dec(J2000) = -21d 08' 52.0"
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 85%.
The mask-weighted lightcurve consists of a single spike (at 64-sec binning).
We note that will only this limited amount of data n the first downlink
we can not say anthing about activity before T-10 sec or after T+57 sec.
When more data has been downlinked, we will issue another Circular.
T90 (15-350 keV) is 0.30 +- 0.05 sec (estimated error including systematics).
The time-averaged spectrum from T-0.1 to T+0.3 is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
0.96 +- 0.28. The fluence in the 15-150 keV band is 4.6 +- 0.8 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T-0.40 sec in the 15-150 keV
band is 1.3 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90%
confidence level.
- GCN NOTICE
TITLE: GCN/SWIFT NOTICE
NOTICE_DATE: Sun 17 Dec 06 13:08:33 UT
NOTICE_TYPE: Swift-XRT Position
TRIGGER_NUM: 251634, Seg_Num: 0
GRB_RA: 160.4098d {+10h 41m 38.3s} (J2000),
160.5040d {+10h 42m 00.9s} (current),
159.7324d {+10h 38m 55.7s} (1950)
GRB_DEC: +21.1264d {+21d 07' 35.0"} (J2000),
+21.0899d {+21d 05' 23.6"} (current),
+21.3881d {+21d 23' 17.2"} (1950)
GRB_ERROR: 4.7 [arcsec radius, statistical plus systematic, 90% containment]
GRB_INTEN: 1.70e-13 [erg/cm2/sec]
GRB_SIGNIF: 4.00 [sigma]
IMG_START_DATE: 14086 TJD; 351 DOY; 06/12/17
IMG_START_TIME: 13282.00 SOD {03:41:22.00} UT, 73.8 [sec] since BAT Trigger Time
TAM[0-3]: 327.61 237.19 261.35 242.66
AMPLIFIER: 2
WAVEFORM: 134
SUN_POSTN: 265.04d {+17h 40m 11s} -23.36d {-23d 21' 34"}
SUN_DIST: 110.96 [deg] Sun_angle= 7.0 [hr] (West of Sun)
MOON_POSTN: 225.83d {+15h 03m 20s} -21.70d {-21d 41' 54"}
MOON_DIST: 76.77 [deg]
MOON_ILLUM: 10 [%]
GAL_COORDS: 217.29, 59.87 [deg] galactic lon,lat of the burst
ECL_COORDS: 153.91, 11.90 [deg] ecliptic lon,lat of the burst
COMMENTS: SWIFT-XRT Coordinates.
COMMENTS: This Notice was ground-generated -- not flight-generated.
COMMENTS: TAM values are not valid.
COMMENTS: This is a ground-calculated position
- GCN Circular #5931
S. D. Barthelmy (GSFC), J. Norris (Stanford U), H. Ziaeepour (MSSL)
on behalf of the Swift-BAT team:
After several more downlinks, the complete data set has arrived for
BAT GRB 061217 (trigger #251634) (Barthelmy, et al., GCN Circ. 5926 and
Parsons, et al,, GCN Circ 5930). Spanning T-120 to T+180 sec,
there is no evidence for pre-trigger activity or post-trigger activity.
The spectral lag for this burst is -7 +- 9 msec (25-50 keV to 100-350 keV)
using 8-msec binning. This is consistent with "zero lag" for
short hard bursts.
- GCN Circular #5932
P. A. Evans, A.P. Beardmore, O. Godet, R.L.C. Starling (U. Leicester) and
H. Ziaeepour (MSSL) report on behalf of the Swift-XRT team:
We have analysed the first 4 orbits (up to 17ks after the trigger) of
Swift-XRT data obtained for GRB 061217 (Barthelmy et al. GCN circ, 5926)
Using ~7.3ks of Photon Counting (PC) data, we find a fading source at
RA(J2000) = 10 41 38.3
Dec(J2000) = -21 07 35.16
with an estimated error radius of 4.7 arcsec (90% confidence, using the
updated teldef file as described by Burrows et al. in GCN Circ. 5750).
This is 82 arc seconds from the refined BAT position (Barthelmy et al. GCN
circ, 5930). Note that there was a typing error in the original position
notice, which gave the declination as positive.
The source has an initial count rate of 0.03 counts s-1 and is
following a power-law decay, with a slope of alpha=0.35 (+0.27,-0.25).
The time-averaged Photon Counting mode spectrum can be modelled with a
power-law with a photon index of 9.998 (+0.001, -1.360), and galactic
absorbtion only (nH=4.51e20 cm-2). The observed (unabsorbed) flux for this
spectrum is 1.70e-13 (4.60e-13) erg cm-2 s-1.
If the decay continues with a slope of alpha = 0.35, the estimated count
rate at 24 hours is 2.4e-3 count s-1. This corresponds to an observed
(unabsorbed) flux of 9.82e-14 (2.65e-13) erg cm-2 s-1.
This circular is an official product of the Swift-XRT team.
- GCN Circular #5933
M. Jel=EDnek, A. J. Castro-Tirado (IAA-CSIC, Granada),
J. Aceituno, A. Guijarro (CAHA, Almer=EDa), A. Monreal (AIP
Potsdam), J. Alfonso (CSIC Madrid), A. de Ugarte Postigo and
J. Gorosabel (IAA-CSIC), on behalf of a larger collaboration,
report:
"Following the detection by SWIFT of the short-duration GRB 061217
(Barthelmy et al. GCNC 5926, Parsons et al. GCNC 5930), we have obtained
BVR images at the 3.5m telescope (+PMAS) at the German-Spanish Calar Alto
Observatory. They were taken starting on Dec 17.1796 UT (i.e. 38 min
post-burst), under good seeing conditions (1".0).
The co-added frames (360s in R) starting 70 min after the
event do not reveal any new sources within the 4".7 radius of
the Swift/XRT position (Evans et al., GCN 5932) when comparing
to the DSS-2 red.=20
There may be an R=3D22.1 faint object at the 3-sigma level, at
coordinates (J2000) 10:41:38.22 -21:07:35.13 +-0.5''.
Further observations are planned."
This message can be quoted.
- GCN Circular #5934
M. De Pasquale, H. Ziaeeepour, M. Chester, M.J. Page
report on the behalf of the Swift UVOT team:
The Swift/UVOT began observing the field of the short GRB GRB061217
4917 seconds after the BAT trigger (Barthelmy et al., GCN Circ. 5926).
No optical afterglow candidate is detected in the XRT error circle of
source S1, the likely X-ray afterglow reported by Evans et al. GCN
circ. 5932, in the first V and White exposures or in the coadded
ones. We quote 3-sigma magnitude upper limits.
Filter T_start T_end Exposure 3s u.l.
(s) (s) (s)
==========================================
White 4917 5017 100 19.2
V 5024 5223 200 19.2
White 4917 11602 1343 20.6
V 5024 17392 1278 20.3
B 5842 7474 393 20.2
U 5637 7269 342 19.8
UVW1 5433 7065 393 19.7
UVM2 5228 17725 717 20.4
UVW2 5464 13325 997 20.6
==========================================
We note that source S1 lies about 10'' from the bright - V~17.6 - galaxy
which is also visible in the Supercosmos scans of the UKST sky survey
plates.
The magnitudes quoted above are not corrected for the expected small
Galactic extinction of E_{B-V} = 0.045 mag (Schlegel et al. 1998).
- GCN Circular #5935
B. E. Cobb (Yale), part of the larger SMARTS consortium, reports:
Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 061217
(GCN 5926, Barthelmy et al.) with a mid-exposure time of
2006-12-17 05:50:32 UT, which is ~2.2 hours post-burst.
Total summed exposure times amounted to 15 minutes in I and V and
12 minutes in J and K. Unfortunately, our images were
centered on the initial BAT GRB coordinates, so that the position
of the X-ray afterglow (GCN 5932, Evans et al.) was not covered
by our IR imaging.
In the X-ray afterglow error region, no new source is detected in
either our I or V-band images to limiting magnitudes of I<21.5
and V<22 (calibrated against USNO-B1.0 stars).
No bright galaxy candidates are detected within about 20 arcsecond
of the X-ray afterglow. The following four stellar-profile sources
are detected in that area:
RA = 10:41:37.96, Dec = -21:07:31.93 (USNO-B1.0 0688-0249429)
RA = 10:41:37.64, Dec = -21:07:52.57 (USNO-B1.0 0688-0249427)
RA = 10:41:39.65, Dec = -21:07:35.52 (USNO-B1.0 0688-0249436)
RA = 10:41:39.75, Dec = -21:07:40.75
There are also 2 very dim sources in that 20 arcsecond radius area:
RA = 10:41:39.17, Dec = -21:07:32.77
RA = 10:41:37.01, Dec = -21:07:35.13
These might be galaxies, but their nature is unclear
since they are detected just at the limit of our imaging.
- GCN Circular #5939
P. D'Avanzo, S. Covino, G. Tagliaferri (INAF-OABr & Univ. Insubria) and
L. Stella (INAF-OAR) report on behalf of the MISTICI collaboration:
We performed a small set of short exposures with the VLT equipped with
the ISAAC camera on the field of the short GRB061217 (Barthelmy et al.,
GCN 5926). Our observations started on Dec 18.262 UT (about 1.1 d after
the burst). While we clearly detect the four point-like objects reported
by Cobb et al. (GCN 5935), we do not detect any candidate for the host
galaxy of GRB061218 inside or near the XRT error-box (Evans et al. GCN
5932) up to a limiting magnitude of H > 20.3 (3sigma level).
This message can be cited.
- GCN Report 21.1
GCN_Report 21.1 has been posted:
http://gcn.gsfc.nasa.gov/reports/report_21_1.pdf
by H.Ziaeepour
at MSSL/UCL
titled: "Swift Observations of GRB 061217"
- GCN Circular #5942
Klotz, A. (CESR-OMP), Boer M. (OHP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 061217 detected by SWIFT
(trigger 251634) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.
The observations started 20.2s after the GRB trigger
(8.1s after the notice). The elevation of the field increased from
from 24 degrees above horizon and weather conditions
were excellent.
The date of trigger : t0 = 2006-12-17T03:40:07.968
We examined the XRT position provided by
Evans et al. 2006 (GCN Circ. 5932).
The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT with a limiting magnitude of:
t0+20.2s to t0+80.2s : R > 16.5
The second image is 30.0s exposure in tracking mode:
t0+87.1s to t0+117.1s : R > 18.1
We co-added a series of exposures:
t0+87.1s to t0+370.6s : R > 19.2
Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.
We have also images from TAROT La Silla
but they were obtained at lower elevation.
So limiting magnitudes are less high.
N.B. Galactic coordinates are lon=266.5898 lat=+32.4491
and the galactic extinction in R band is 0.1 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.
This message may be cited.
- GCN Circular #5947
P.A. Evans, K.L. Page (U. Leicester) and J.A. Kennea (PSU) report on
behalf of the Swift/XRT team:
The XRT position of GRB 061217 reported in GCN Circ. 5932 was incorrect
due to analysis of the early XRT data being compromised by the faintness
of the source and its proximity to the hot columns. Having reprocessed
the complete set of XRT observations of GRB 061217, we find the
corrected position to be:
RA (J2000) : 10 41 39.10
Dec (J2000): -21 07 26.9
with an uncertainty of 6.0" (90% confidence).
This circular is an official product of the Swift team.
- GCN Circular #5948
H. Ziaeepour (UCL-MSSL), S. D. Barthelmy (GSFC), A.P. Beardmore (U.
Leicester), D. N. Burrows (PSU), J. Cummings (GSFC/UMBC), M. De Pasquale
(UCL-MSSL), P. A. Evans (U. Leicester), N. Gehrels (GSFC), O. Godet (U.
Leicester), M. Page (UCL-MSSL), J. Osborne (U. Leicester), A. P. Parsons
(GSFC), J. L. Racusin (PSU), M. Stamatikos (GSFC/ORAU), R.L.C. Starling
(U. Leicester), G. Tagliaferri (INAF) report on behalf of the Swift Team
GRB 061217 was a short hard burst without any detected optical afterglow
by Swift or ground follow-ups. There is a source at ~11 arcsec from the
new XRT position (Evans, et al GCN 5947) in the SuperCosmos catalogue
and is classified as a galaxy. Its position:
RA (J2000) = 10 41 39.6
Dec (J2000) = -21 07 35.5
and magnitudes:
B = 18.5
R1 = 16.9
It is also observed by UVOT (GCN 5934, mag. B ~18.3, V~17.6) and during
follow-up of this burst by SMARTS (GCN 5935) and VLT (GCN 5939). We
encourage the observation of this source to confirm its classification
as a galaxy and determine its redshift, if relevant.
- GCN Circular #5949
E. Berger (Carnegie) reports:
"We observed the location of GRB 061217 with LDSS3 on the Magellan 6.5-m
telescpe starting on 2006 Dec. 21.36 UT in r-band. In a single 300 sec
exposure with 0.55" seeing we clearly detect an extended object (G1)
within the revised XRT position (GCN #5947) at:
RA = 10:41:39.15
DEC=-21:07:27.3
A second, much fainter object with apparently extended morphology (G2) is
located on the southern edge of the error circle at:
RA = 10:41:39.10
DEC=-21:07:33.1
We propose that object G1 is the host galaxy of GRB 061217."
- GCN Circular #5950
E. Berger (Carnegie) reports:
"The object proposed as the host galaxy of GRB 061217 in GCN 5948 (located
11 arcsec from the revised XRT position), appears to have a stellar point
spread function in both our IMACS (GCN #529) and LDSS3 (GCN #5949) images.
We re-iterate the presence of an extended object within the XRT error
circle (GCN #5949)."
- GCN Circular #5951
A. de Ugarte Postigo, A. J. Castro-Tirado, J. Gorosabel,
M. Jel=EDnek (IAA-CSIC, Granada), J. Aceituno, A. Guijarro
(CAHA, Almer=EDa), A. Monreal (AIP Potsdam), J. Alfonso
(CSIC Madrid), J.A. Caballero (MPIE)
on behalf of a larger collaboration,
report:
"We have revised the R band images obtained from the 3.5m
telescope (+PMAS) at Calar Alto (Jel=EDnek et al. GCN 5933) and we
detect an object in the refined error box of XRT (Evans et al GCN
5932) at the following coordinates (J2000) with an uncertainty
of 0.5":
R.A.: 10:41:39.06
Dec.: -21:07:20.7
This object seems to be stable in subsequent images obtained
from the 2.5m INT (+WFC) on 18.24 UT Dec 2006. This supports
the identification of the host galaxy candidate reported by Berger
et al. (GCN 5949) A finding chart is available at:
http://www.iaa.es/~deugarte/GRBs/061217/061217.gif
This message can be quoted.
- GCN Circular #5953
N. Butler (U.C. Berkeley) reports:
We centroid on a faint and fading source 20" away from the initial refined
XRT team position (GCN5932). Using 6 optical/X-ray matches, we find an
astrometry corrected position (v2.9) relative to 2MASS of:
RA, Dec: 10 41 39.32 -21 07 22.1 ; +/-3.8" (90% Conf.) (J2000.0)
The candidate from GCN5948 is 14" from our position, however this is likely
a star (GCN5949). Our position is 5.7" away from Source G1 in GCN5949 and
11.4" away from Source G2 in GCN5949. Our position therefore favors
associating source G1 with the short GRB host galaxy.
Our position has remained stable for several days as new XRT data
reach our computers (http://astro.berkeley.edu/~nat/swift/xrt_pos.html).
The reductions, which take into account bad detector columns, are described in
Butler (2006; AJ accepted; astro-ph/0611031). The disagreement of our
position with the original XRT team refined position lead to a retraction
of that position. The new XRT team position (GCN5947) is consistent with
ours.
Thanks to J. Bloom and A. Kann for helping to discover the discrepancy
with the XRT Team position.
- GCN Circular #5965
E. Berger (Carnegie) reports:
"We obtained a 2100 sec spectrum of the putative host galaxy of the short
GRB 061217 (GCN #5949). We clearly detect the [OII]3727 and [OIII]5007
emission lines at a redshift of z=0.827. The relative faintness of the
host and the higher redshift compared to early short GRBs provides
additional support to the conclusion that a substantial fraction of short
GRBs arise at z~1 (Berger et al. astro-ph/0611128). At z=0.827 the
isotropic-equivalent energy release of the burst is about 8e49 erg."
- GCN Report 21.2
GCN_Report 21.2 has been posted:
http://gcn.gsfc.nasa.gov/reports/report_21_2.pdf
by H. Ziaeepour
at MSSL/UCL
titled: "Final Report on Swift Observations of GRB 061217"
- GCN Circular #6060
Scapin V. and Garczarczyk M., Bastieri D., Fagiolini M., Galante N.,
Gaug M., Longo F., Mizobuchi S., Piccioli A. and Stamerra A.
report for the MAGIC collaboration:
The MAGIC Imaging Atmospheric Cherenkov Telescope performed a follow-up
observation of the SWIFT-BAT burst GRB061217 (GCN circular 5926,
Barthelmy S.D. et al.). We received the GCN alert at T0+13s, however,
because of observation constraints, data taking with MAGIC started at
T0+773s, when the GRB zenith angle reached 60 degree. The observation
continued for 66min.
No evidence for VHE gamma-ray emission above the analysis threshold of
325 GeV was found. A preliminary analysis, for the hypothesis of steady
emission and assumption of a differential photon spectral index of -2.5,
yields the following 95% CL differential flux upper limits (inc. 30%
systematic error on the absolute flux level):
E(300-500 GeV) : 0.53 x 10^(-10) erg/cm^2/s
E(500-1000 GeV) : 0.35 x 10^(-10) erg/cm^2/s
The upper limits apply of the time window between T0+773s and T0+2573s
(the first 30min of the MAGIC data sample).
This message can be cited.
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