GRB 080710
GCN Circular 7973
Subject
GRB 080710: Optical observation with MITSuME Okayama
Date
2008-07-11T23:35:57Z (18 years ago)
From
Michitoshi Yoshida at Okayama Astrophysical Obs <yoshida@oao.nao.ac.jp>
M. Yoshida, K. Yanagisawa, D. Kuroda, Y. Shimizu, S. Nagayama,
H. Toda (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf
of the MITSuME collaboration:
We observed the optical afterglow (Li et al. GCN 7959; D'Avanzo
et al. GCN 7960; Schady GCN 7961) of GRB 080710 (Sbarufatti
et al. GCN 7957) with the optical three color (g', Rc and Ic)
imager attached to the MITSuME 50cm telescope of Okayama
Astrophysical Observatory. We started the observation at
2008-07-10 15:37:23 UT. Photometric results are listed below.
We used four USNO-B1.0 stars around the afterglow. The Rc band
magnitude is consistent with the power-law decay with alpha = 1.5
reported by Schulze et al. (GCN 7972).
mid-UT of the observation:
2008-07-10 16:27:00 (0.384595 days after trigger)
T-T0(days) exp-T g' Rc Ic
----------------------------------------------------------------
0.384595 86min 18.79 +/- 0.08 18.96 +/- 0.06 18.57 +/- 0.06
----------------------------------------------------------------
GCN Circular 7972
Subject
GRB 080710: TLS observations, steepening afterglow decay
Date
2008-07-11T14:14:53Z (18 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
S. Schulze, D. A. Kann, A. Rossi, E. Gonsalves, C. Hoegner and B. Stecklum
(TLS Tautenburg) report:
We observed the optical afterglow location (Li et al., GCN 7959) of Swift
GRB 080710 (Sbarufatti et al., GCN 7957) with the TLS 1.34m Schmidt
telescope under inclement but improving conditions. 600 second B and V
observations were affected by passing clouds and yielded no detections and
shallow upper limits only. We detect the afterglow clearly in a single Rc
image as well as in four Ic images (600 seconds each) before dawn shut us
down. We measure afterglow magnitudes against eight USNOB1.0 stars in each
case:
time (days) filter magnitude exposure
0.7275 Rc 20.05 +/- 0.12 600
0.7468 Ic 19.75 +/- 0.13 4 x 600
In comparison with the magnitude as well as the slope reported from the
Faulkes Telescope North (Bersier et al., GCN 7963) (R = 17.8 at 4.4h,
alpha = 0.82), our measurement implies a significant steepening of the
decay, we find alpha = 1.5 between 4.4 and 17.5 hours after the GRB. This
implies that a break must have occurred inbetween, and possibly the slope
during the time of our observations is already > 2 and the break is a jet
break.
Using the redshift of 0.845 (Perley et al., GCN 7962) as well as the
values derived in the BAT refined analysis (Tueller et al., GCN 7969) and
estimating the peak energy following equation 3 of Liang et al. (2007,
ApJ, 670, 565), we derive a bolometric isotropic energy release of 6.8
+2.0 -1.9 x 10^51 erg. If there is a jet break before 17 hours, this would
imply a low collimation-corrected energy release.
No further observations from TLS are possible due to an instrument change.
This message may be cited.
GCN Circular 7970
Subject
GRB 080710: Lick IR detection
Date
2008-07-11T03:20:32Z (18 years ago)
From
Daniel Perley at U.C. Berkeley <dperley@astro.berkeley.edu>
D. A. Perley (UC Berkeley) and C. Melis (UCLA) report:
On the night of 2008-07-10 starting at 10:32:30 UT, we began a series of
IR exposures with the Lick Shane 3 meter telescope, equipped with the
GEMINI IR imager. We acquired imaging in J and K' filters
simultaneously between 10:32 and 10:44. We returned to the field during
morning twilight and took additional imaging between 12:19 and 12:25 in
H and K' simultaneously.
Calibrating to two nearby 2MASS stars, we estimate a preliminary
magnitude in the first epoch J-band imaging of:
J = 16.24 +/- 0.05
between 10:32 and 10:44 (mid-time of 206 minutes after the GRB.)
The GRB afterglow displays tentative evidence of brightening over the
exposure period. Additional analysis is ongoing.
GCN Circular 7969
Subject
GRB 080710, Swift-BAT refined analysis
Date
2008-07-11T01:16:10Z (18 years ago)
From
Takanori Sakamoto at NASA/GSFC <takanori.sakamoto-1@nasa.gov>
J. Tueller (GSFC), S. D. Barthelmy (GSFC), W. Baumgartner (GSFC/UMBC),
J. Cummings (GSFC/UMBC), E. Fenimore (LANL), N. Gehrels (GSFC),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), K. McLean (GSFC/UMD),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (GSFC/ORAU), T. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 080710 (trigger #316534)
(Sbarufatti, et al., GCN Circ. 7957). The BAT ground-calculated position is
RA, Dec = 8.259, 19.484 deg which is
RA(J2000) = 00h 33m 02.2s
Dec(J2000) = +19d 29' 00.8"
with an uncertainty of 2.3 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 48%.
The mask-weighted light curve shows a weak emission starting around T-120 sec,
and then, following a FRED like spike starting from T+0 sec and ending at
T+43 sec. T90 (15-350 keV) is 120 +- 17 sec (estimated error including systematics).
The time-averaged spectrum from T-96.9 to T+43.3 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.47 +- 0.23. The fluence in the 15-150 keV band is 1.4 +- 0.2 x 10^-06 erg/cm2.
The 1-sec peak photon flux measured from T+0.89 sec in the 15-150 keV band
is 1.0 +- 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/316534/BA/
GCN Circular 7967
Subject
GRB 080710: Rapid PROMPT Observations
Date
2008-07-10T22:30:01Z (18 years ago)
From
Thomas Summers Brennan at UNC/GRB Group <bre@email.unc.edu>
E. Weaver, J. P. West, D. Reichart, M. Nysewander, A. LaCluyze, K.
Ivarsen, J. A. Crain, A. Foster, T. Brennan, J. Haislip, R. Holmes, R.
Rhine, M. Schubel, J. Styblova, and A. Trotter report:
Skynet observed the localization of GRB 080710 (Sbarufatti et al., GCN
7957) with three of the 16" PROMPT telescopes at CTIO beginning 64
seconds after the trigger in BVRI.
We detect the afterglow (Sbarufatti et al., GCN 7957) in BVRI. At 627
seconds after the burst we measure B ~ 17.7 mag (calibrated to 9 USNO
B1 stars), at 626 seconds we measure V ~ 17.6 mag (calibrated to 12
USNO B1 stars), at 535 seconds we measure R ~ 17.6 mag (calibrated to
13 NOMAD stars), and at 444 seconds we measure I ~ 16.9 mag
(calibrated to 11 USNO B1 stars).
GCN Circular 7966
Subject
GRB 080710: Swift-XRT refined analysis
Date
2008-07-10T22:14:47Z (18 years ago)
From
Boris Sbarufatti at INAF-IASF-Pa <sbarufatti@ifc.inaf.it>
B. Sbarufatti, V. Mangano (INAF/IASF Pa) report on behalf of the
Swift XRT team
Swift XRT began observations of GRB 080710 (Sbarufatti et al., GCN
Circ. 7957) at 08:02 UT, 49 minutes after the trigger. The refined
position for
the afterglow, obtained using the XRT-UVOT alignment and matching UVOT
field sources to the USNO-B1 catalogue (see Evans et al., GCN Circ.
7964)
is RA, Dec = 8.27364, 19.50158 which is equivalent to:
RA (J2000): 00 33 5.67
Dec (J2000): +19 30 05.7
with an uncertainty of 1.4 arcsec (radius, 90% confidence).
The XRT observations consist of 7.9 ks in Photon Counting mode. The
light-curve can be fitted by a simple power-law model with slope (1.0
+/- 0.1),
with superposed flaring activity.
The average spectrum can be modeled by a power-law with photon index
2.09
+/-0.1 and an intrinsic absorbing column of (1.6 +/-0.7) E21 cm^-2 at
z=0.845 (Perley et al., GCN Circ. 7962) in excess with respect to the
Galactic
value (4.1E+20 cm^-2, Kalberla et al. 2005). The observed
(unabsorbed) flux in
the 0.3-10 keV band is 5.35 (5.84)E-12 ergs cm^-2 s^-1. The count
rate to flux
conversion factor is 4.1E-11.
The predicted flux for tomorrow, 07:13 UT (24 h after the trigger) is
6.9E-13 ergs cm^-2 s^-1.
This circular is an official product of the Swift XRT team.
GCN Circular 7965
Subject
GRB080710: Swift/UVOT observations
Date
2008-07-10T18:50:43Z (18 years ago)
From
Wayne Landsman at GSFC/SSAI <wayne.b.landsman@nasa.gov>
W.B. Landsman (NASA/GSFC) and B. Sbarufatti(INAF-OAB) report on behalf
of the Swift/UVOT team
The Swift/UVOT observed the field of GRB 08710 starting at 3186s after
the BAT trigger ( Sbarufatti et al., GCN 7957). We detect the afterglow
in all seven UVOT filters at the position
RA(J2000.0) = 00:33:05.65
DEC(J2000.0) = +19:30:05.3
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence).
This position is consistent with the enhanced XRT position (Evans et al.
GCN 7964) and the KAIT afterglow position (Li et al., GCN 7959). The
detection in the UVW2 (1950 A) filter is consistent with the redshift of
~0.845 estimated from spectroscopic observations by Perley et al. (GCN
7962). The
white and v exposure are consistent with a decay slope of alpha ~-0.8,
as also found by Bersier and Gomboc (GCN 7963).
The magnitudes with 1 sigma errors are reported below.
Filter TMid(s) Expo(s) Magnitude
-----------------------------------------------------
white 3185 98 16.88 +/- 0.02
white 5615 186 17.37 +/- 0.03
v 3342 197 17.06 +/- 0.06
v 10560 295 17.79 +/- 0.08
b 5416 197 17.56 +/- 0.05
u 5211 197 16.70 +/- 0.04
uvw1 5006 197 16.86 +/- 0.06
uvm2 3477 58 17.08 +/- 0.17
uvw2 9344 777 17.88 +/- 0.05
-----------------------------------------------------
The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E{B-V} = 0.07 mag (Schlegel et al.
1998). The photometry is on the UVOT flight system described in Poole
et al. (2008,MNRAS,383,627).
GCN Circular 7964
Subject
GRB 080710: Enhanced Swift-XRT position
Date
2008-07-10T18:00:38Z (18 years ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester)
report on behalf of the Swift-XRT team.
Using 8101 s of XRT Photon Counting mode data and 10 UVOT
images for GRB 080710, 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 = 8.27364, +19.50158 which is equivalent
to:
RA (J2000): 00h 33m 5.67s
Dec (J2000): +19d 30' 05.7"
with an uncertainty of 1.4 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, A&A, 476, 1401
http://www.swift.ac.uk/xrt_positions/Goad.pdf), the current algorithm is an
extension of this method.
This circular was automatically generated, and is an official product of the
Swift-XRT team.
GCN Circular 7963
Subject
GRB 080710: Faulkes Telescope North observations
Date
2008-07-10T14:20:13Z (18 years ago)
From
David Bersier at Liverpool John Moores U <dfb@astro.livjm.ac.uk>
D. Bersier (Liverpool JMU) and A. Gomboc (U. Ljubljana)
report on behalf of a larger collaboration:
We observed GRB 080710 (Sbarufatti et al. GCN 7957) with the 2m
robotic Faulkes Telescope North. We obtained multi-colour images
(BVRi) starting 4.2 hours after the burst. We confirm the presence of
a fading source at the position of the afterglow (Li et al. GCN 7959;
D'Avanzo et al GCN 7960). At a time of 4.4 hours after burst we
measure an R-band magnitude of 17.8 (calibrated with respect to USNO
R2). The decay rate is approximately -0.82.
We note that the afterglow is well detected in the B band, indicating
a rather low redshift (in agreement with Perley et al. GCN 7962).
Observations are continuing.
GCN Circular 7962
Subject
GRB 080710: Gemini spectroscopy and probable redshift
Date
2008-07-10T12:00:49Z (18 years ago)
From
Daniel Perley at U.C. Berkeley <dperley@astro.berkeley.edu>
D. A. Perley, R. Chornock, and J. S. Bloom report on behalf of a larger
collaboration:
Starting at 09:25 UT on 2008 July 10 we began spectroscopy of the
optical counterpart (Li et al., GCN 7959) of GRB 080710 (Sbarufatti et
al., GCN 7957) using Gemini-South (+GMOS). We acquired 2x1200s
integrations using the B600 grism, covering a wavelength range from 3800
to 6700 Angstroms.
The spectrum shows several strong absorption features, corresponding to
the Mg II (2796+2803) doublet, Fe II (2586+2600) doublet, Mg I (2853),
and Fe II (2344+2374+2382) at a common redshift of z=0.845. We
tentatively associate this redshift with GRB 080710. Additional
analysis of the spectrum is ongoing.
We thank the Gemini staff for conducting these observations.
GCN Circular 7961
Subject
UVOT white band observations of GRB080710
Date
2008-07-10T10:42:45Z (18 years ago)
From
Patricia Schady at MSSL/Swift <ps@mssl.ucl.ac.uk>
P. Schady (MSSL-UCL) reports on behalf of the Swift/UVOT team:
The UVOT began observing the field of GRB 080710 3138.2s after the BAT
trigger. A single white band finding chart was downlinked promptly, and
a bright, uncatalogued source with magnitude wh = 16.88+/-0.02 is
detected at
RA = 00:33:05.67 = 8.27363
Dec = +19:30:04.69 = 19.50130
with an uncertainty of 0.5 arcseconds (90% confidence), consistent with
the XRT position (Sbarufatti et al., GCN 7958) and KAIT position
(Chornock et al., GCN 7959).
The value quoted above has not been corrected for the expected Galactic
extinction corresponding to a reddening of E(B-V) = 0.08 mag in the
direction of the burst (Schlegel et al. 1998).
GCN Circular 7960
Subject
GRB 080710: REM afterglow confirmation & brightening
Date
2008-07-10T10:05:04Z (18 years ago)
From
Paolo D'Avanzo at INAF-OAB <paolo.davanzo@brera.inaf.it>
P. D'Avanzo, D. Fugazza, L.A. Antonelli, L. Calzoletti, S. Campana,
G. Chincarini, S. Covino, M.L. Conciatore, S. Cutini, V. D'Elia, F.
D'Alessio, F. Fiore, P. Goldoni, D. Guetta, C. Guidorzi, G.L. Israel,
E. Maiorano, 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 080710 (Sbarufattion et al. GCN 7957,
7958) on July 10 starting at 07:14:36 UT.
We can detect in optical and NIR bands the object reported by Li et al.
(GCN 7959). The object is variable and we measure a brightening from H ~
15.0 to H ~14.3 between two epochs of observations (arount 07:21 and
08:47 UT, respectively). Further analysis is ongoing.
GCN Circular 7959
Subject
GRB 080710: KAIT OA candidate
Date
2008-07-10T09:46:14Z (18 years ago)
From
Weidong Li at UC Berkeley KAIT/LOSS <weidong@astron.berkeley.edu>
W. Li, R. Chornock, D. A. Perley, and A. V. Filippenko,
University of California at Berkeley, on behalf of the KAIT
GRB team, report:
KAIT responded to GRB 080710 (Swift trigger 316534; Sbarufatti et al.,
GCN 7957; Sbarufatti et al., GCN 7958) and started to take images at
09:10:20 UT, 1.953 hours after the BAT trigger. There is an optical
afterglow at position
RA = 00:33:05.64
DEC = +19:30:05.7
(equinox J2000)
The measured magnitude is R = 16.8 in a 20s unfiltered image,
calibrated to USNO B1. Observations are ongoing.
GCN Circular 7958
Subject
GRB 080710: Swift XRT position
Date
2008-07-10T08:29:46Z (18 years ago)
From
Vanessa Mangano at INAF-IASFPA <vanessa@ifc.inaf.it>
B. Sbarufatti (INAF-IASFPA), P. A. Evans (U Leicester)
and V. Mangano (INAF-IASFPA) report on behalf of the Swift Team:
The XRT began observing the field at 08:05:22.4 UT, 3131.6 seconds
after the BAT trigger. Using promptly downlinked data we find an
uncatalogued X-ray source located at RA, Dec 8.27344, 19.50157 which is
equivalent to:
RA(J2000) = 00h 33m 5.63s
Dec(J2000) = +19d 30' 05.7"
with an uncertainty of 3.2 arcseconds (radius, 90% containment). This
location is 65 arcseconds from the BAT onboard position, within the BAT
error circle.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value
(4.1e+20 cm^-2, Kalberla et al. 2005), with an excess column of
2 (+2.03/-1.73) x 1021 cm^-2 (90% confidence).
GCN Circular 7957
Subject
GRB 080710: Swift detection of a burst
Date
2008-07-10T07:29:01Z (18 years ago)
From
Boris Sbarufatti at INAF-IASF-Pa <sbarufatti@ifc.inaf.it>
B. Sbarufatti (INAF-IASFPA), W. H. Baumgartner (GSFC/UMBC),
P. A. Evans (U Leicester), C. Guidorzi (INAF-OAB),
E. A. Hoversten (PSU), V. La Parola (INAF-IASFPA),
V. Mangano (INAF-IASFPA), C. B. Markwardt (CRESST/GSFC/UMD),
K. L. Page (U Leicester), P. Romano (INAF-IASFPA) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:
At 07:13:10 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 080710 (trigger=316534). The BAT on-board calculated location is
RA, Dec 8.257, +19.492 which is
RA(J2000) = 00h 33m 02s
Dec(J2000) = +19d 29' 31"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a single-peaked
structure with a duration of about 20 sec. The peak count rate
was ~1,000 counts/sec (15-350 keV), at 0 sec after the trigger.
Due to an observing constraint, Swift will not slew until
T0+49.5 minutes. There will be no XRT or UVOT data until
this time.
Burst Advocate for this burst is B. Sbarufatti (sbarufatti AT ifc.inaf.it).
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.)