GRB 060507
GCN Circular 5084
Subject
GRB 060507: Swift detection of a burst
Date
2006-05-07T02:28:01Z (19 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
L. M. Barbier (NASA/GSFC), S. D. Barthelmy (GSFC),
M.L. Conciatore (ASDC), J. R. Cummings (NASA/ORAU),
N. Gehrels (NASA/GSFC), C. Gronwall (PSU),
C. B. Markwardt (GSFC/UMD), D. M. Palmer (LANL),
A. M. Parsons (GSFC), M. Perri (ASDC), M. Stamatikos (NASA/GSFC/ORAU)
and L. Vetere (ASDC) report on behalf of the Swift Team:
At 01:53:12 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 060507 (trigger=208870). Swift did not slew because
of Earth observing constraint. The BAT on-board calculated location is
RA,Dec 89.972,+75.237 {05h 59m 53s,+75d 14' 13"} (J2000) with an uncertainty
of 3 arcmin (radius, 90% containment, including systematic uncertainty).
The lightcurve shows multiple peaks starting at ~T-8 sec and ending ~T+25 sec
with a peak count rate of ~1000 counts/sec at ~T+1 sec.
Because of an Earth limb constraint, the spacecraft did not slew promptly
to the BAT position, and so there are no immediate XRT and UVOT data products
to analyze.
GCN Circular 5085
Subject
GRB060507: Swift XRT position
Date
2006-05-07T03:29:29Z (19 years ago)
From
Loredana Vetere at ASDC <vetere@asdc.asi.it>
L. Vetere, M.L. Conciatore, M. Perri (ASDC), D.N. Burrows (PSU) and
L. M. Barbier (NASA/GSFC) report on behalf of the Swift/XRT team:
The Swift XRT began observing GRB 060707 (trigger #208870, Barbier et
al., GCN 5084) at 02:39:33 UT, 46 minutes after the BAT trigger.
Analysis of the initial TDRSS downliked data reveals a faint and
uncataloged
source at the following coordinates:
RA(J2000) = 05h 59m 51.9s
Dec(J2000) = +75d 14' 56"
with an estimated uncertainty of 7.5 arcseconds (90% containment).
This position lies 43 arcseconds from the center of the BAT error circle
reported in GCN 5084.
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 becomes available.
This circular is an official product of the Swift XRT Team.
GCN Circular 5086
Subject
GRB 060507: MDM Optical Upper Limit
Date
2006-05-07T03:45:58Z (19 years ago)
From
Jules Halpern at Columbia U. <jules@astro.columbia.edu>
J. P. Halpern (Columbia U.) and N. Mirabal (U. Michigan) report
on behalf of the MDM Observatory GRB follow-up team:
"We took a single 60 s R-band exposure of the Swift BAT location of
GRB 060507 (Barbier et al., GCN 5084) with the MDM 1.3m telescope
on May 7 02:57 UT, 64 minutes after the trigger. We see no new object
within the 3' error circle, or at the XRT candidate position of
Vetere et al. (GCN 5085), to a limit of approximately R=19.2.
Evening twilight and telescope pointing constraints prevent any
further observations.
This message may be cited."
GCN Circular 5087
Subject
GRB 060507: Swift XRT Team Refined Analysis
Date
2006-05-07T17:10:01Z (19 years ago)
From
Loredana Vetere at ASDC <vetere@asdc.asi.it>
L. Vetere, M.L. Conciatore, M. Capalbi, M. Perri (ASDC),
D.N. Burrows (PSU) and L. M. Barbier (NASA/GSFC) report on
behalf of the Swift/XRT team:
We have analysed the first 5 orbits of XRT data from GRB 060507
(Barbier et al., GCN 5084).
A 11ks photon counting mode image provides a refined XRT position:
RA(J2000) = 05 59 51.7
Dec(J2000) = +75 14 56.6
with an uncertainty of 4 arcsec (90% containment). This is 1 arcsec
away from the initial XRT position quoted in GCN 5085 (Vetere et al.).
The X-ray light curve decays with a single powerlaw, fitting the last
4 orbits we find a decay index of -1.0 +/- 0.1.
A power-law fit to the X-ray spectrum from T+2.8ks to T+28.3ks gives a
photon
index of 2.1+/-0.1 and a column density of (1.7+/-0.4)e21 cm^-2. We note
that the galactic hydrogen column density in the direction of the burst
is 8.8e20cm^-2. The 0.2-10.0 keV observed flux is 2.2e-12 ergs
cm^-2 s^-1, which corresponds to an unabsorbed flux of 3.4e-12 ergs
cm^-2 s^-1.
If the burst continues decaying at the current rate we estimate an XRT
count rate of 0.009 counts/s at T + 24hr, which corresponds to an
observed 0.2-10.keV flux of 6.8e-13 ergs cm^-2 s^-1.
This circular is an official product of the Swift XRT Team.
GCN Circular 5088
Subject
GRB 060507: Swift/UVOT Upper Limits
Date
2006-05-07T17:12:56Z (19 years ago)
From
Frank Marshall at GSFC <marshall@milkyway.gsfc.nasa.gov>
F. E. Marshall and L. M. Barbier (NASA/GSFC) report on behalf
of the Swift/UVOT team:
The Swift UVOT began observing GRB 060507 (trigger #208870, Barbier et
al., GCN 5084) 46 minutes after the BAT trigger.
No optical afterglow is detected inside the error region of the
candidate XRT afterglow (Vetere et al. GCN 5085).
Typical upper limits for a 3.5 arc sec aperture are given below
for the initial UVOT exposures. T is the time since
the BAT trigger in seconds at the start of the exposure.
No correction has been made for the expected extinction
corresponding to E(B-V) = 0.16 mag.
T Exposure filter 5-sigma UL
(sec) (sec)
2790 98 White 19.4 mag
2896 197 V 18.7 mag
9567 295 White 20.6 mag
GCN Circular 5090
Subject
GRB 060507: Swift-BAT Refined Analysis
Date
2006-05-08T02:49:57Z (19 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
J. Tueller (GSFC), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (BYU-Idaho), H. Krimm (GSFC/USRA), M. Koss (UMD),
C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/ORAU), G. Sato (ISAS), M. Stamatikos (GSFC/ORAU),
on behalf of the Swift-BAT team:
Using the data set from T-239 to T+963 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 060507 (trigger #208870)
(Barbier, et al., GCN 5089). The BAT ground-calculated position is
RA,Dec = 89.935,+75.243 deg {5h 59m 44.3s,+75d 14' 36.1"} (J2000)
+- 5.0 arcmin, (radius, sys+stat, 90% containment). The partial coding
was 33%.
The light curve shows an initial peak with a long decay, followed by
a series of smaller peaks between T+100 and T+200 seconds.
Currently, there are four gaps in the telemetry downlinked data
which prevent us from analyzing this burst between T-42 to T-10.3 sec,
T+78.4 to T+80.6, T+88.7 to T+98.6, and T+167.4 to T+170.6 sec.
T90 (15-350 keV) is 185 +- 5 sec (estimated error including systematics).
The very long duration and absence of short timescale spikes in the
lightcurve could be indicative of a high redshift event.
The time-averaged spectrum from T-10 to T+192 (minus the gaps listed above)
is best fit by a simple power-law model. The power law index of the
time-averaged spectrum is 1.83 +- 0.09. Because of the data gaps,
the lower limit on the fluence in the 15-150 keV band is
4.1 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured from
T+1.24 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 Circular 5091
Subject
GRB 060507: Final Refined analysis of the Swift-BAT burst
Date
2006-05-08T21:18:07Z (19 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
L. Barbier (GSFC), S. Barthelmy (GSFC), J. Cummings (GSFC/ORAU),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
T. Sakamoto (GSFC/ORAU), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Now having recieved the full downlinked data that fills in the gaps
(Tueller et al, GCN 5090), we report the updated refined analysis
on Swift-BAT GRB 060507 (trigger 208870).
The lightcurve description in GCN 5090 does not change, nor does T90.
The time-averaged spectrum from T-10.2 to T+192.4 is best fit by
a simple power-law model. The power law index of the time-averaged
spectrum is 1.83 +- 0.09. The fluence in the 15-150 keV band is
4.5 +- 0.2 x 10^-6 erg/cm2. The 1-sec peak photon flux measured
from T+1.24 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 Circular 5092
Subject
GRB 060507: BART limit
Date
2006-05-08T22:12:42Z (19 years ago)
From
Martin Jelinek at Inst.Astrophys.Andalucia,Granada <mates@iaa.es>
Martin Jelinek (IAA Granada),
Petr Kubanek (ISDC Versiox and ASU Ondrejov),
Rene Hudec, Martin F. Nekola, Filip Munz
and Jan Strobl (ASU Ondrejov)
report
Telescope BART in Ondrejov observatory in Czech Republic
observed the Swift-detected GRB 060507 (Barbier et al, GCN
5084; Vetere et al, GCN 5085; Vetere et al, GCN 5087; Tueller
et al, GCN 5090; Barbier et al, GCN 5091) starting 60.3s after
the GRB trigger.
We do not detect any new source in the XRT nor BAT errorboxes.
Particularly we set the first 60s unfiltered exposure 3-sigma
limit calibrated using USNO-A2.0 R-band as R>15.5.
GCN Circular 5094
Subject
GRB060507: optical afterglow detection
Date
2006-05-09T13:17:15Z (19 years ago)
From
Christina Thoene at Niels Bohr Institute,DARK Cosmo Ctr <cthoene@astro.ku.dk>
Christina C. Thoene, Brian L. Jensen, Johan Fynbo (Dark Cosmology Centre),
Jan-Erik Solheim (University of Oslo), and Erika Pakstiene
(TFAI, University of Vilnius) report
We observed the field of GRB060507 (GCN 5084) in the I-band with the NOT
and ALFOSC on La Palma, starting at May 7th, UT 03:08:19 (1.13h after the
burst) at high airmass. On the edge of the XRT revised error circle (99%
confidence) (GCN 5087) we detect a new source at the position (J2000)
RA = 05:59:50.52
Dec = +75:14:55.9
The preliminary I-band magnitude obtained from 3x300s stacked images with
a mean time of 1.3h after the burst is
I = 19.1 +- 0.1
(compared to four nearby USNO stars)
5x300 I-band images from May 9th show that the source is transient and
therefore likely to be the afterglow of GRB060507
A finding chart is available at:
http://www.astro.ku.dk/~brian_j/grb/grb060507.079/
[GCN OPS NOTE(10may06): Per author's request, the E.P. author was added.]