GRB 080205
GCN Circular 7250
Subject
GRB 080205: Swift detection of a burst
Date
2008-02-05T08:21:36Z (17 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
C. B. Markwardt (CRESST/GSFC/UMD), M. M. Chester (PSU),
J. R. Cummings (NASA/UMBC), P. A. Evans (U Leicester),
A. D. Falcone (PSU), N. Gehrels (NASA/GSFC), C. Guidorzi (INAF-OAB),
S. T. Holland (CRESST/USRA/GSFC), S. D. Hunsberger (PSU),
J. A. Kennea (PSU), C. Pagani (PSU), K. L. Page (U Leicester),
D. M. Palmer (LANL), D. Perez (U Leicester), J. L. Racusin (PSU),
T. Sakamoto (NASA/UMBC), M. Stamatikos (NASA/ORAU),
R. L. C. Starling (U Leicester), T. N. Ukwatta (GSFC/GWU) and
L. Vetere (PSU) report on behalf of the Swift Team:
At 07:55:51 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080205 (trigger=302506). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 98.219, +62.769 which is
RA(J2000) = 06h 32m 53s
Dec(J2000) = +62d 46' 07"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows three roughly
equal-height peaks spanning approximately 120 seconds. The peak
count rate was ~1000 counts/sec (15-350 keV), at ~0 sec, ~70 sec,
and ~95 sec after the trigger.
XRT began observing at 07:57:32 UT, 101 s after the BAT trigger.
Using prompt downlinked data, we find a bright, fading, uncatalogued
X-ray source located at RA, Dec 98.2561, 62.7913 deg which is
RA(J2000) = 06h 33m 1.46s
Dec(J2000) = +62d 47' 30.1"
with an uncertainty of 3.0 arcsec (radius, 90% containment).
This location is 100 arcseconds from the BAT on-board position,
within the BAT error circle.
UVOT took a finding chart exposure of 100 seconds with the White (160-650 nm)
filter starting 112 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 3-sigma upper limit at the XRT position is 19.2 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 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.09.
Burst Advocate for this burst is C. B. Markwardt (craigm AT milkyway.gsfc.nasa.gov).
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 7251
Subject
GRB 080205: KAIT OA detection
Date
2008-02-05T08:27:42Z (17 years ago)
From
Weidong Li at UC Berkeley KAIT/LOSS <weidong@astron.berkeley.edu>
W. Li, D. Perley, R. J. Foley, A. V. Filippenko, and J. S. Bloom,
University of California, Berkeley, on behalf of the KAIT GRB team,
report:
The robotic 0.76-m Katzman Automatic Imaging Telescope (KAIT) at Lick
Observatory observed GRB 080205 detected with Swift (Trigger 302506)
The automatic sequence started at 07:56:56, 64.3 s after the burst.
The BAT location has been monitored in V, I, and clear filters, with
varying exposure times. Our image processing pipeline found a new
object within the BAT error circle, with the following position:
R. A. = 06:33:00.64
DEC. = +62:47:32.0 (J2000)
The OA has magnitude of 17.0 (calibrated with USNO B1.0) in a 20s
unfiltered exposure started at 08:01:45 UT, and show apparent variability.
Further observations are on-going.
This message may be cited.
GCN Circular 7252
Subject
GRB 080205: Enhanced Swift-XRT position
Date
2008-02-05T13:16:25Z (17 years ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester)
report on behalf of the Swift-XRT team.
Using 794 s of overlapping XRT Photon Counting mode and UVOT
V-band data for GRB 080205, 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 = 98.25223, +62.79186 which is equivalent
to:
RA (J2000): 06h 33m 0.54s
Dec (J2000): +62d 47' 30.7"
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 7253
Subject
GRB 080205: Swift/UVOT observations
Date
2008-02-05T16:16:32Z (17 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S.R. Oates (MSSL-UCL) and C.B Markwardt (CRESST/GSFC/UMD) report
on behalf of the UVOT team.
The Swift/UVOT observed the field of GRB 080205 (trigger #302506)
starting 111 seconds after the BAT trigger (Markwardt et al., GCN
Circ. 7250). We detect the optical afterglow at the position:
RA (J2000) = 06:33:00.62
Dec (J2000) =+62:47:31.98
with an error of about 0.5". This is consistent with the position
reported by Li et al.(GCN 7251) and lies within the revised
XRT error circle (Osborne et al., GCN 7252).
The optical afterglow initially brightens in the first few hundred seconds
after the trigger and then begins to decay at around ~T+1000s. The
afterglow is detected in the white and v filters only. The lack
of detection in the b, u and uv filters suggests that this GRB is
at a z ~ 4.0.
The magnitudes and 3-sigma upper limits are listed:
Filter Tstart(s) Tstop(s) Exp Magnitude
--------------------------------------------------------------
white 111 211 98 20.37 +/- 0.28 (3.7-sigma)
864 964 98 19.76 +/- 0.17 (6.2-sigma)
5436 5636 196 20.59 +/- 0.25 (4.2-sigma)
v 217 617 393 18.07 +/- 0.09 (11.4-sigma)
970 1370 393 19.02 +/- 0.20 (5.4-sigma)
b 697 686 451 20.83 (3 sigma UL)
u 672 6664 471 20.45 (3 sigma UL)
uvw1 647 6458 286 20.13 (3 sigma UL)
uvm2 622 7525 329 20.03 (3 sigma UL)
uvw2 727 7279 452 20.39 (3 sigma UL)
--------------------------------------------------------------
The values quoted above are not corrected for the expected Galactic
extinction corresponding to a reddening of E_{B-V} = 0.091 mag in the
direction of the burst (Schlegel et al. 1998).
GCN Circular 7254
Subject
GRB 080205: OA evolution from KAIT observations
Date
2008-02-05T16:25:04Z (17 years ago)
From
Alex Filippenko at UC Berkeley <alex@astro.berkeley.edu>
W. Li, D. Perley, and A. V. Filippenko, University of California,
Berkeley, on behalf of the KAIT GRB team, report:
We report further analysis of the KAIT observations of GRB 080205
(Swift Trigger 302506; Markwardt et al. GCN 7250) announced by
Li et al. (GCN 7251). Preliminary reduction of the unfiltered
data shows that the optical afterglow (OA) has a nearly constant
brightness of mag 18.1 from t = 65 s to 90 s, declines to mag 19.1
by t = 171 s, rises to mag 16.9 by t = 537 s, and has a steep
power-law decline (with index around -1.6) thereafter until
at least t = 50 min. The OA is also detected in multiple I-band
and V-band images, suggesting that the redshift of the GRB is lower
than roughly 4 or 5. The overall behavior of the OA of GRB 080205
is similar to that of GRB 060206 (Monfardini et al. 2006, ApJ,
648, 1125).
This message may be cited.
GCN Circular 7255
Subject
GRB 080205: Swift XRT refined analysis
Date
2008-02-05T17:45:32Z (17 years ago)
From
Rhaana Starling at U of Leicester <rlcs1@star.le.ac.uk>
R.L.C. Starling (U. Leicester) and C.B. Markwardt (CRESST/GSFC/UMD) report
on behalf of the Swift XRT team:
Swift XRT observations of GRB 080205 (trigger=302506) began 101 seconds
after the BAT trigger (Markwardt et al., GCN 7250) in Windowed Timing mode
and continued in Photon Counting (PC) mode 208 s after the trigger. The
enhanced XRT position is given in Osborne et al. GCN 7252.
The light curve out to 13.5 ks post-trigger can be fit with a power law
with two breaks. The initial steep decay has a slope of alpha1 = 4.5+/-0.3
breaking at Tbk1 = 203+20/-8 s to a plateau with slope alpha2 = 0.4+/-0.4.
The plateau phase ends at Tbk2 = 570+170/-120 s and the decay continues
with alpha3 = 1.8+/-0.1.
We fit the first orbit PC mode spectrum, totalling 1.5ks of data and
covering T0+208s-T0+1728s, with an absorbed power law. We measure a photon
index of Gamma = 1.8+/-0.2 and intrinsic absorption of N_H = (1.0+/-0.7)e21
cm^-2 (at z=0), whilst fixing the Galactic absorption at 7.1e20 cm^-2
(Kalberla et al. 2005).
The 0.5-10 keV observed (unabsorbed) flux is 6e-11 (7.2e-11) erg/cm^2/s.
The count rate to flux conversion is approximately 1 count/s = 4.7e-11
erg/cm^2/s.
The predicted count rate at T+24h is 2e-4 counts/s, or 1e-14 erg/cm^2/s.
This is an official product of the Swift XRT team.
GCN Circular 7257
Subject
GRB 080205, Swift-BAT refined analysis
Date
2008-02-05T18:38:21Z (17 years ago)
From
Takanori Sakamoto at NASA/GSFC <Taka.Sakamoto@nasa.gov>
J. Cummings (GSFC/UMBC), S. D. Barthelmy (GSFC), E. Fenimore (LANL),
N. Gehrels (GSFC), H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD),
D. Palmer (LANL), T. Sakamoto (GSFC/UMBC), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+963 sec from the recent telemetry
downlink, we report further analysis of BAT GRB 080205 (trigger #302506)
(Markwardt, et al., GCN Circ. 7250). The BAT ground-calculated
position is RA, Dec = 98.261, 62.782 deg which is
RA(J2000) = 6h 33m 2.6s
Dec(J2000) = 62d 46' 56"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 52%.
The mask-weighted light curve shows at least 3 peaks at about T+2,
T+65, and T+93 sec. T90 (15-350 keV) is 106.5 +- 5.0 sec (estimated
error including systematics).
The time-averaged spectrum from T-10.1 to T+105.3 sec is best fit by a
simple power-law model. The power law index of the time-averaged
spectrum is 2.08 +- 0.12. The fluence in the 15-150 keV band is
2.1 +- 0.1 x 10^-06 erg/cm2. The 1-sec peak photon flux measured from
T+0.22 sec in the 15-150 keV band is 1.4 +- 0.2 ph/cm2/sec.
All the quoted errors are at the 90% confidence level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/302506/BA/
GCN Circular 7258
Subject
INT+WFC R-band observations of GRB 080205
Date
2008-02-06T03:12:46Z (17 years ago)
From
Evert Rol at U.Leicester <er45@star.le.ac.uk>
E. Rol (U. of Leicester) and J. Anderson (LJMU) report for a larger
collaboration:
We observed the position of GRB 080205 with the Isaac Newton Telescope
equipped with the Wide Field Camera at Roque de Los Muchachos.
Observations were carried out in R-band, for 30 minutes starting at 23:05
UT.
We detect the afterglow with a magnitude of R = 23.50 +/- 0.11; our
photometry is calibrated to several USNO B1.0 R2 magnitudes.
Compared with the early (unfiltered) 17.0 magnitude KAIT measurement
(Li et al., GCN 7251), this indicates a slightly shallower powerlaw
decay than the initial -1.6 (Li et al, GCN 7254), suggestive of
underlying contamination by a host galaxy. At the source position,
however, there is no clear evidence for extended emission.
GCN Circular 7259
Subject
VLA radio upper limit on GRB 080205
Date
2008-02-06T12:41:08Z (17 years ago)
From
Poonam Chandra at U Virginia/NRAO <pc8s@virginia.edu>
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
080205 (GCN 7250) at a frequency of 8.46 GHz on 2008 February 6.13 UT. The
GRB is undetected and the peak radio flux at the SWIFT-XRT position (GCN
7252) is 30 +/- 41 uJy.
The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."
GCN Circular 7260
Subject
GRB 080205: optical observation
Date
2008-02-06T13:30:27Z (17 years ago)
From
Giuseppe Greco at U Bologna <giuseppe.greco2@studio.unibo.it>
F. Terra, (Second University of Roma "Tor Vergata"), G. Greco,
C. Bartolini, A. Guarnieri, A. Piccioni (Bologna University),
D. Nanni(INAF/OAR and Second University of Roma "Tor Vergata"),
G. Pizzichini (INAF/IASF Bologna), G. Gavazzi (Milano-Bicocca
University) and A. De Blasi (INAF Bologna) report:
We observed the field of GRB 080205 (Markwardt et al. GCN 7250)
with the 152 cm Loiano telescope under modest sky (cirrus)
and seeing (2.5") conditions.
Our observation was carried out in R-band,
for 20 minutes starting on 2008 February 5, 22:28 UT.
We do not detect the OT reported by Li et al. (GCN 7251)
to a limiting magnitude of R ~ 20 based on the NOMAD catalog.
GCN Circular 7261
Subject
GRB 080205: MASTER optical observation
Date
2008-02-06T14:37:12Z (17 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
D.Kuvshinov, V. Lipunov, V.Kornilov, E.Gorbovskoy, N.Tyurina, A.Belinski,
A.Krylov, N.Shatskiy, A.Sankovich, V.Vladimirov,
P.Gritsyk, V.Vibornov, A.Kuznetsov, P.Balanutsa
Sternberg Astronomical Institute, Moscow Union 'Optic'
MASTER robotic system (http://observ.pereplet.ru) observed
GRB 080205 (GRB_TIME is 08:21:36 UT, Markwardt et al. GCN Circ 7250 ) in
survey mode (the GRB was at day time for Moscow).
The weather was good.
We have 31 images from 16:22:35 to
17:24:46 (481 - 545 minutes after the GRB time) with mean time:
16 54 UT (513 min after GRB time).
The unfiltered image is calibrated relative to USNO A2.0 (0.8 R + 0.2 B).
The robot not find OT brighter then 19.5m at KAIT's position (Li et
al., GCN Circ 7251).
Our limit is agreement with power low line between Li et al.,(GCN
Circ 7254) and Rol & Anderson (GCN CIRC 7258) observations.
This message can be cited.
Mailto: lipunov@sai.msu.ru
GCN Circular 7262
Subject
GRB 080205 optical upper limit
Date
2008-02-06T14:46:31Z (17 years ago)
From
AAVSO GRB Network at AAVSO <matthewt@aavso.org>
Stefano Sposetti (Gnosca, Switzerland) reports to the AAVSO International
High Energy Network the following optical observations of GRB080205 (GCN
#7250, Markwardt et al.):
Stefano Sposetti reports an upper limit on the optical afterglow of
GRB080205 reported by Li et al (GCN #7251). The reported afterglow
position was observed for a total of 7200 seconds using a 0.4-meter
Newtonian with an SBIG ST8XE CCD and no filter. Observations commenced on
2008 February 05.74, approximately 9.5 hours after the Swift-BAT
detection. The afterglow was not detected, and an upper limit of CR=21.0
was obtained with a S/N of 3, using USNO A2.0 magnitudes as comparisons.
This upper limit is consistent with the R < 20 upper limit by Terra et al.
(GCN #7260) at 2008 February 05.94, and the R = 23.5 detection at 2008 Feb
05.96 by Rol et al. (GCN #7258).
A detailed report on these observations is available on the AAVSO website
at ftp://ftp.aavso.org/grb/StefanoSposetti_GRB080205_2454502.86049_.txt
A fits image is available at
ftp://ftp.aavso.org/grb/StefanoSposetti_GRB080205_2454502.86049_.fits
The AAVSO thanks the Curry Foundation for their continued support of the
AAVSO International High Energy Network.
GCN Circular 7275
Subject
GRB 080205: RTT150 optical observations
Date
2008-02-08T21:02:03Z (17 years ago)
From
Rodion Burenin at IKI, Moscow <rodion@hea.iki.rssi.ru>
R. Burenin, A. Tkachenko, M. Pavlinsky, R. Sunyaev (IKI),
I. Khamitov, Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.),
I. Bikmaev, N. Sakhibullin (KSU/AST)
report:
The optical counterpart of GRB 080205 (Li et al., GCN 7251) was observed
with Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National
Observatory, Turkey). We made two sets of BVRI images on Feb 05
approximately at 18:00 and 22:00 UT (10 and 14 hours after the burst). The
afterglow is detected near the limit of our images, i.e. near about R=23.5
(USNO B1.0 calibrated), in agreement with later INT observation (Rol and
Anderson, GCN 7258).
GCN Circular 7278
Subject
GRB 080205: GAO 150cm telescope Optical limit
Date
2008-02-09T12:31:49Z (17 years ago)
From
Kenzo Kinugasa at Gunma Astro. Obs/Japan <kinugasa@astron.pref.gunma.jp>
K. Kinugasa (Gunma Astronomical Observatory) report:
The field of GRB 080205 (Markwardt et al. GCN 7250) was observed
with the 150 cm telescope of the Gunma Astronomical Observatory.
Starting at 14:42 UT (6.35 hours after the burst), Rc, and Ic frames
were acquired for 15 and 18 minutes, respectively.
We do not identify the optical counterpart reported by Li et al. (GCN 7251).
to limiting magnitudes of R~20 and I~18 relative to USNO-B1.0 magnitudes.
GCN Circular 7332
Subject
GRB080205: optical observations
Date
2008-02-26T17:05:10Z (17 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
V. Rumyantsev (CrAO), V. Biryukov (SAI, MSU), E. Klunko (ISTP), M. Andreev
(Terskol Branch of Institute of Astronomy), A.J. Castro-Tirado (IAA-CSIC),
A. Pozanenko (IKI) on behalf of larger GRB follow up collaboration report:
We observed the afterglow (Li at al, GCN 7251), of GRB080205 (Palmer et
al, GCN7250) with 1.5m telescope of Sayan observatory (Mondy) on Feb.05 in
BR and Feb.06; with Zeiss-600 of Mt. Terskol observatory on Feb.05 in R; and
with CrAO Shajn 2.6m telescope in BVRI on Feb.05, and on Feb.06. In CrAO
observations we detected afterglow in R, V and not detected in B, I on
Feb.05. We do not detect afterglow in any observations on Feb.06.
T0+ Exposure R_mag (err) UL Site seeing
(mean)
0.226 d 40x60 s n/d 21.1 Mondy 2.2"
0.379 d 30x60 s 22.26 (0.19) 23.0 CrAO 1.5"
0.409 d 20x90 s n/d 20.3 Terskol 2.0"
0.548 d 34x60 s 22.26 (0.15) 23.3 CrAO 1.4"
0.772 d 40x60 s n/d 22.4 CrAO 1.4"
1.530 d 123x60 s n/d 23.8 CrAO 1.7"
Preliminary photometry reduction is based on USNO-B1.0 stars.
Taking together KAIT (Li at al. GCN 7254) and ING (Rol et al. GCN 7258)
observations one can suggest some episodes of a light curve of the GRB080205
afterglow: the steep decline of light curve with power law index about -1.6
between 537 s - 50 m (Li at al. GCN 7254), the shallow decay with power law
index of -0.9 between T0+ 50m - 9h, plateau (or rebrightening) between T0+
9h - 13h, and after then very steep decline. The data after ~50 m after
burst onset is also compatible with a single power law with index -1.1 and
a bump between 9h - 13h. Since we do not detect afterglow on Feb.06
(R>23.8) it is most probably that the previous phases of the light curve is
not contaminated by a host galaxy. Our non detection of the afterglow in
B-filter confirms the redshift less than ~4 (Oates at al. GCN 7253, Perley
at al. GCN 7254).
The message may be cited.