GRB 060202
GCN Circular 4629
Subject
GRB 060202: Swift detection of a burst
Date
2006-02-02T09:33:04Z (19 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
D. Fox (PSU), S. Barthelmy (GSFC), D. Burrows (PSU), J. Cummings (GSFC/NRC),
N. Gehrels (GSFC), S.T. Holland (GSFC/USRA), S. Hunsberger (PSU),
H. Krimm (GSFC/USRA), D. Morris (PSU), D. Palmer (LANL)
on behalf of the Swift team:
At 08:40:55 UT, Swift-BAT triggered and located GRB 060202 (trigger=179968).
The spacecraft slewed immediately. The BAT on-board calculated location
is RA,Dec 35.843d,+38.362d {02h 23m 22s,+38d 21' 43"} (J2000),
with an uncertainty of 3 arcmin (radius, 90% containment, stat+sys).
This was a 64-sec image trigger. The BAT light curve shows a broad and
weak peak with a total duration of >20 sec. The peak count rate was
~500 counts/sec (15-350 keV), at ~5 seconds after the trigger.
XRT began observing the GRB at 08:43:18 UT, 143.3s after the BAT trigger.
A bright, uncatalogued, fading source, was found by the on-board
centroiding algorithm at
RA(J2000)=02h 23m 23.1s
DEC(J2000)=+38d 23' 09.2"
with an uncertainty of 6 arcseconds radius (90% containment).
This position lies 87 arcseconds from the center of the BAT error
circle. The XRT count rate clearly decreases as a power law
in the first 100s. The initial XRT flux was ~2.5E-8 ergs/cm2/s.
UVOT took a finding chart exposure of 200 seconds with the V filter
starting 148 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. The typical 3-sigma upper limit has been
about 18th mag. The 8'x8' region for the list of sources generated
on-board covers 100% of the XRT error circle. The list of sources is
typically complete to about 18.0 mag. No correction has been made for
the expected extinction of about 0.2 magnitudes.
GCN Circular 4630
Subject
GRB060202: Faulkes North observation
Date
2006-02-02T11:20:32Z (19 years ago)
From
Cristiano Guidorzi at ARI,Liverpool JMU <crg@astro.livjm.ac.uk>
A. Monfardini, C.G. Mundell, C. Guidorzi, I. A. Steele, A. Gomboc,
C.J. Mottram, R.J. Smith, D. Bersier, A. Melandri, S. Kobayashi,
D. Carter, M.F. Bode (Liverpool JMU), P. O'Brien, E. Rol, N. Bannister
(U. of Leicester) report:
"The 2-m Faulkes Telescope North robotically followed up GRB060202
(SWIFT trigger 179968) 4.2 min after the GRB trigger time.
We do not detect any obvious optical candidate within the
XRT error circle (Fox et al., GCN 4629).
Limiting magnitudes have been derived with reference to USNOB1."
Exposure Filter Start Time End Time Lim. Mag.
(since GRB) (since GRB) (5sig)
-----------------------------------------------------
3x10s R 4.2 min 5.0 min 20.0
410 s R 4.2 min 32.5 min 21.5
400 s i' 7.7 min 36.2 min 20.5
-----------------------------------------------------
GCN Circular 4631
Subject
GRB 060202 : Lulin R and I band limit
Date
2006-02-02T14:04:55Z (19 years ago)
From
Kuiyun Huang at IANCU <d919003@astro.ncu.edu.tw>
M. Yang, K.Y. Huang, W.H. Ip (NCU),
Y. Urata(RIKEN), Y. Qiu (BAO), Y.Q. Lou (THCA) on behalf of EAFON
report:
"A set of R and I band imaging observation using LOT (One-meter
telescope at Lulin Observatory, Taiwan) started at 10.9 UT. No
variable source was detected in the XRT error region (Fox et al. GCN
4629) at our co-add R and I band images. The limiting magnitude of I
and R band were calibrated against USNO-B1.0 catalog.
Mid-UT(hrs) Exp-time Filter limiting mag. (3-sigma)
----------------------------------------------------------
2.35 3x300s R ~21.2
2.72 3x300s I ~19.5
This message may be cited."
GCN Circular 4632
Subject
GRB 060202: Swift XRT Team Refined Analysis
Date
2006-02-02T14:24:33Z (19 years ago)
From
Jamie A. Kennea at PSU/Swift-XRT <kennea@astro.psu.edu>
D. Morris (PSU), D. Fox (PSU), D. Burrows (PSU), N. Gehrels (GSFC), F.
Marshall (GSFC), P. Boyd (GSFC-UMBC), J. Kennea (PSU), H. Krimm
(GSFC/USRA), D. Palmer (LANL) report on behalf of the Swift XRT team:
We have analyzed the Swift XRT data from the first orbit observation of
GRB 060202 (Fox et al., GCN4629), with a total exposure of 540 seconds.
The refined XRT position is:
RA(J2000) = 02h 23m 23.02s
Dec(J2000) = +38d 23' 05.7"
This position is 82.8 arcseconds from the BAT and 3.7 arcseconds from the
XRT position given in GCN 4629. We estimate an uncertainty of 4 arcseconds
radius (90% containment).
The 0.2-10 keV light curve in Windowed Timing (WT) mode starts 148.8
seconds from the BAT trigger (T0). The lightcurve shows a steep early
decay index of 2.7 followed by a flattening to a decay index of 0.2 at
T+310 s.
A preliminary spectral fit to the WT data gives a spectral power law
photon index of 2.52 +/- 0.03 in the [0.2-10] keV band with NH of 5.8e21 +/-
2e20, well above the galactic NH value for this direction of 5.1e20. The
unabsorbed 0.2-10 keV flux at the start of the XRT observation is
estimated to be about 2.5E-8 erg/cm2/s, flattening at a flux level of
about 2E-9 erg/cm2/s. We do not have sufficient data at this time to allow
an accurate extrapolation of the flux to T+24 hr.
GCN Circular 4633
Subject
GRB 060202: Swift/UVOT upper limits
Date
2006-02-02T16:44:58Z (19 years ago)
From
Alexander Blustin at MSSL-UCL <ajb@mssl.ucl.ac.uk>
A. J. Blustin (UCL-MSSL), D. Fox (PSU), B. Hancock (UCL-MSSL),
T. Kennedy (UCL-MSSL), N. Gehrels (GSFC) on behalf of the
Swift/UVOT team report:
The Swift/UVOT began taking data on the field of GRB 060202 at
08:43:09 UT on 2006-02-02, 134 s after the BAT trigger (Fox et al.,
GCN 4629). No afterglow candidate is detected in summed images in
any filter within the refined XRT error circle (Morris et al., GCN
4632) down to the following 3-sigma magnitude upper limits.
Filter T_range(s) Exp(s) 3sigUL(mag)
V 134-1231 449 19.6
B 355-1025 419 20.5
U 656-4847 91 19.1
UVW1 633-4840 119 18.7
UVM2 608-4816 119 19.2
UVW2 561-4768 99 19.0
These magnitudes are uncorrected for Galactic extinction;
E(B-V) = 0.047. We note that the XRT position is 19 arcseconds
away from the nearest star in the DSS.
GCN Circular 4634
Subject
GRB060202, optical observation
Date
2006-02-02T17:15:34Z (19 years ago)
From
Eri Sonoda at U of Miyazaki/Japan <sonoda@astro.miyazaki-u.ac.jp>
E.Sonoda,S.Maeno,S.Masuda,Y.Nakamura,M.Yamauchi
(University of Miyazaki)
"We have observed the field covering the error circle of
GRB060202 (GCN 4629) with the unfiltered CCD camera on
the 30-cm telescope at University of Miyazaki.
The observation was started 09:28:22 UT, 47.45 min
after the Swift trigger time.
After co-adding a set of 14 images (09:40:34 - 09:57:32 UT)
of 30 sec exposures, we have compared with the USNO A2.0 catalog.
Preliminary analysis shows there is no new source brighter
than 16.9 mag."
GCN Circular 4635
Subject
GRB 060202: Refined analysis of the Swift-BAT burst
Date
2006-02-02T17:29:35Z (19 years ago)
From
Craig Markwardt at NASA/GSFC/UMD <craigm@milkyway.gsfc.nasa.gov>
D. Hullinger (GSFC/UMD), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/NRC), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hinshaw (GSFC-SPSYS), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
K. McLean (LANL), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/NRC), G. Sato (ISAS), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Using the data set from T-300 to T+303 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 060202 (trigger #179968)
(Fox, et al., GCN 4629). The BAT ground-calculated position
is (RA,Dec) = 35.822, 38.381 deg {2h 23m 17.3s, 38d 22' 53.3"} (J2000)
+- 2.0 arcmin, (radius, sys+stat, 90% containment). The partial coding
was 61%.
The mask-tagged light curve shows two broad main peaks with roughly
equal peak count rates. The first peak is from approximately T-40 to
T+40 sec and the second roughly from T+ ~70 to T+210 sec. The second
peak appears to be spectrally softer than the first peak. We note
that XRT observations (Morris, et al, GCN 4632) started at T+148.8
seconds and thus overlapped with ~70 seconds of the prompt emission
detected by BAT. T90 (15-350 keV) is (203.7 +- 20) sec (estimated
error including systematics).
The time-averaged spectrum from T-36.1 to T+196.6 is best fit by
a simple power-law model. The power law index of the time-averaged
spectrum is 1.78 +- 0.13. The fluence in the 15-150 keV band
is (2.4 +- 0.2) x 10^-06 erg/cm2. The 1-sec peak photon flux measured from
T-6.46 sec in the 15-150 keV band is (0.5 +- 0.2) ph/cm2/sec.
All the quoted errors are at the 90% confidence level.
GCN Circular 4636
Subject
GRB 060202: Optical Afterglow Candidate from Keck/LRIS
Date
2006-02-03T09:23:20Z (19 years ago)
From
S. Bradley Cenko at Caltech <cenko@srl.caltech.edu>
S. B. Cenko, D.-S. Moon, (Caltech), and B. P. Schmidt (MSO-ANU) report on
behalf of a larger collaboration:
We have imaged the field GRB060202 (Fox et al., GCN 4629) with the
Low-Resolution Imaging Spectrometer mounted on the 10-m Keck I telescope.
Observations consisted of 2 x 300 s images taken simultaneously in the
g and I filters at a mean time of approximately February 3.22. Images
were taken under good seeing conditions, though shortly after sunset with
a high background.
Inside the revised XRT error circle (Morris et al., GCN 4632), we find one
faint source (S1) in our I-band images detected at approximately the
2-sigma level. The location of this source is (J2000):
RA: 02:23:22.88
Dec: +38:23:04.3
with an approximate error of 1.0" in each coordinate. The magnitude of
this object, with reference to the USNO-B2 catalog, is approximately I =
22.6 +/- 0.3, with photometric calibration dominating the errors. We find
no source in our g-band coadd at this location to a limiting magnitude of
approximately g > 22.0. We note this position is consistent with the
detection of a K-band source with UKIRT by Wang et al. (private
communication, GCN forthcoming).
There is one additional source (S2), of similar magnitude and color,
located just outside the edge of the XRT error circle, which we include
for completeness. The location of this source (J2000.0) is:
RA: 02:23:22.80
Dec: +38:23:08.9
While we cannot comment on variability at this time, we propose that the
source S1 is the afterglow of GRB 060202.
The early R-band limits provided by Monfardini et al. (GCN 4630) indicate
a red R-I color for this potential afterglow. Given the possibility that
this object is at high redshift (z > 5), we have triggered Gemini NIR
imaging of the field. A report on these observations will follow in
a subsequent GCN.
GCN Circular 4637
Subject
GRB 060202: Near-IR Observation with UKIRT/WFCAM
Date
2006-02-03T12:30:56Z (19 years ago)
From
Yuko Kakazu at U of Hawaii/Inst. for Astro. <kakazu@ifa.hawaii.edu>
W-H. Wang (UH/IfA), Y. Kakazu (UH/IfA), B. P. Schmidt (MSO-ANU),
and L. L. Cowie (UH/IfA)
We have imaged the field GRB060202 (Fox et al., GCN 4629)
with the UKIRT Wide Field Camera in J and K-band filters from
approximately UT 05:00 to 08:20 on Feb 03.
Observations consisted of 10s expsosures in both J and K with a 9-point
dither pattern with +/-6.4" and 12.8" offsets.
Total integration times for J and K are 60 and 72 minutes, respectively.
Images were processed using the UKIRT real-time pipeline ORACDR and we
tried to obtain a better background subtraction on the final coadded image.
The final image quality is limited by the poor seeing at low elevation and
telescope pointing, and has a PSF of 2".
We detected a faint source inside the revised 4" XRT error circle
(Morris et al., GCN 4632) in K-band images.
The location of this source is:
RA = 02:23:22.94, DEC = +38:23:03.69 (J2000.0)
This is consistent with the Keck/LRIS I-band detection reported
by Cenko et al. (GCN 4636) within 1".
The magnitude of this source is K = 19.86 with 3" aperture diameter,
using nearby 2MASS stars for calibration.
A PSF fit, however, suggests the point component may be almost a magnituder
fainter and there may be some underlying diffuse emission.
In the J band image, we found no source within the XRT error circle
to a 1 sigma limiting magnitude of J > 22.74 [2MASS].
GCN Circular 4638
Subject
GRB 060202 : Kiso B and R band limit
Date
2006-02-03T12:40:25Z (19 years ago)
From
Yuji Urata at RIKEN <urata@crab.riken.go.jp>
M. Abe, K. Kitazato (ISAS/JAXA), H. Mito (U. Tokyo),
Y. Urata (RIKEN), K.Y. Huang, Y. Qiu (BAO)
on behalf of EAFON report:
"We have observed entire error region of GRB 060202 (Fox et al. #4629)
using Kiso 1.05m Schmidt telescope. The set of B and R band images
were taken from 1.67 hours after the burst. The afterglow candidates
(Cenko et al. # 4636) did not appear in combined images. The 3-sigma
limiting magnitude of B and R are 19.8 and 20.5, respectively."
This message may be cited.
GCN Circular 4639
Subject
GRB 060202: Gemini-N J, H, K_s observations
Date
2006-02-03T13:02:32Z (19 years ago)
From
Brian Schmidt at RSAA, ANU (MSSSO) <brian@mso.anu.edu.au>
B. Schmidt (ANU), Edo Berger (OCIW), Yuko Kakazu (IfA), Len Cowie (IfA)
and Brad Cenko (CalTech) on behalf of a larger collaboration report,
"We have imaged the field GRB060202 (Fox et al., GCN 4629) with Gemini-N
+ NIRI in J, H, and K_s filters at approximately UT 06:30, 2006 Feb
03. We confirm the faint source of Cenko et al. (GCN 4636) and Wang et
al. (GCN 4637) inside the revised 4" XRT error circle (Morris et al.,
GCN 4632) in K-band images. We marginally detect the source in J. Using
the 2MASS star at RA=2:23:26.6 DEC=38:23:29 (J2000), we estimate the
magnitude of the source in a 1" aperture to be
J = 23.0 � 0.4
H >= 21.1
K = 20.1 � 0.2
These observations, combined with the results of Cenko et al. and Wang
et al. indicate that GRB060202 is most likely at z<6.
We would like to thank the Staff of Gemini for their help in executing
these Target of Opportunity observations"
GCN Circular 4640
Subject
GRB 060202: GETS observation
Date
2006-02-03T17:42:27Z (19 years ago)
From
Kenzo Kinugasa at Gunma Astro. Obs/Japan <kinugasa@astron.pref.gunma.jp>
K. Kinugasa (Gunma Astronomical Observatory) and K. Torii (Osaka U.) report:
The error region of GRB 060202 (Fox, et al. GCN 4629) was imaged by the
robotic 0.25m GETS telescope in the Gunma Astronomical Observatory.
Unfiltered imaging started at 09:17:06 UT (36.2 minutes after the trigger)
and 30 s integration was repeated.
We can not identify a new object within the XRT error region (Morris, et
al. GCN 4632) and the afterglow candidates (Cenko et al. GCN4636).
The following 3-sigma upper limits are derived relative to USNO-A1.0 R mag.
------------------------------------------
StartUT EndUT Limit Nframes
------------------------------------------
09:17:06 09:17:36 >16.9 1
09:17:06 09:44:31 >19.0 33
------------------------------------------
GCN Circular 4642
Subject
GRB 060202: PROMPT Observations
Date
2006-02-04T02:17:57Z (19 years ago)
From
Chelsea Louise MacLeod at UNC-Chapel Hill/PROMPT <chelseam@physics.unc.edu>
C. MacLeod, J. Haislip, M. Nysewander, A. LaCluyze, D. Reichart, J. A.
Crain, A. Foster, K. Ivarsen, and J. Kirschbrown report on behalf of the
UNC team of the FUN GRB collaboration:
We observed the localization of GRB 060202 (Fox et al., GCN 4629; Morris et
al., GCN 4632) with three of the PROMPT telescopes simultaneously in Ur'I
beginning 16.1 hours after the burst under the automated control of Skynet:
Filter Telescope Start (UT) Stop (UT) Exposures Total (hr)
U PROMPT-2 00:38:20 00:57:40 12 x 80s 0.32
r' PROMPT-4 00:37:37 00:57:57 13 x 80s 0.34
I PROMPT-1 00:38:15 00:57:14 12 x 80s 0.32
No new source is found to I > 19.1 mag (3 sigma; calibrated to seven
USNO-B1.0 stars).
PROMPT is currently being built and commissioned at CTIO.
GCN Circular 4653
Subject
GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
Date
2006-02-04T10:27:15Z (19 years ago)
From
Yuko Kakazu at U of Hawaii/Inst. for Astro. <kakazu@ifa.hawaii.edu>
W.-H. Wang, Y. Kakazu (UH-IfA), B. P. Schmidt (ANU),
L. L. Cowie (UH-IfA), S. B. Cenko, and D.-S. Moon (Caltech)
We have reobserved the field GRB060202 (Fox et al., GCN 4629) with
the Wide Field Camera on UKIRT in K-band filter at a mean epoch of
approximately 5:45 UT on the February 4th.
Our total integration time is 36 min.
We still see the faint source reported by Wang et al. (GCN 4638)
at roughly the same magnitude (K=20.07 in 3" aperture diameter).
We have imaged the same region also with the Low-Resolution
Imaging Spectrometer mounted on the 10-m Keck I telescope.
Observations consisted of 4 x 150 s images taken in the I-band filter
at a mean time about 5:50 UT on February 4th.
The faint source (S1) reported by Cenko et al. (GCN 4636) was detected
at roughly the same magnitude (I = 22.9 +/- 0.3).
Our results suggest that the source S1 is not a GRB afterglow.