GRB 060929
GCN Circular 5668
Subject
GRB 060929: Further XRT Refined Analysis
Date
2006-09-30T13:44:52Z (20 years ago)
From
Kim Page at U.of Leicester <kpa@star.le.ac.uk>
K.L. Page, A.P. Beardmore (U. Leicester) & C.B. Markwardt (GSFC/UMD)
report on behalf of the Swift-XRT team:
We have now analysed the first 9 orbits of XRT data obtained for GRB
060929 (GCN Circ. 5654; Markwardt et al.). Following the large flare
between T+410s and T+1180s reported in GCN Circulars 5662 and 5663 (Palmer
et al.; Beardmore et al.), the X-ray afterglow fades with a decay slope of
0.79 +/- 0.08.
Assuming this rate of decay continues, we predict a count rate of 0.0019
count s^-1 at T+24 hours. Using the spectral fit for the data after the
flare (photon index = 2.5 +/- 0.9) together with a total column density of
1.8e21 cm^-2 (see GCN Circ. 5663), this corresponds to an observed
(unabsorbed) flux of 7.49e-14 (1.41e-13) erg cm^-2 s^-1.
This circular is an official product of the Swift-XRT team.
GCN Circular 5667
Subject
GRB 060929: Swift/UVOT Optical Observations
Date
2006-09-30T13:34:39Z (20 years ago)
From
Shashi Pandey at MSSL <sbp2@mssl.ucl.ac.uk>
S. B. Pandey (UCL-MSSL) and C. B. Markwardt (GSFC/UMD) report on behalf of
the Swift-UVOT team:
The Swift UVOT began observing the GRB 060929 field (trigger 231702), 78
seconds after the BAT trigger (GCN 5654, 5660). No new source was detected
in the co-added UVOT observations down to the following 3-sigma magnitude
upper limits within the refined XRT error circle (GCN 5663):
Filter T_range (s) Exposure (s) 3sigma UL
V 78 - 2356 950 20.71
B 678 - 2295 136 20.55
U 654 - 2271 156 20.25
W1 630 - 2247 156 19.60
M2 606 - 2223 156 19.83
W2 707 - 2333 156 19.98
White 95 - 2309 273 20.96
T_range is calculated from the time of the burst. The upper limits
are not corrected for Galactic extinction E(B-V) = 0.048 along
the line of sight to the burst.
GCN Circular 5663
Subject
GRB060929: Swift-XRT refined analysis.
Date
2006-09-30T03:40:42Z (20 years ago)
From
Andy Beardmore at U Leicester <apb@star.le.ac.uk>
A. P. Beardmore (U. Leicester), D. N. Burrows (PSU), K. L. Page
(U. Leicester) and C. B. Markwardt (GSFC/UMD) report on behalf of
the Swift-XRT team:
We have analysed the first orbit of Swift-XRT data of GRB 060929
(Markwardt et al., GCN 5654).
From 1.9ks of Photon Counting mode data, we derive a refined XRT
position of:
RA(J2000) = 17h 32m 29.0s
Dec(J2000) = +29d 50' 08.9"
with an error radius of 5.5 arcsec (90% confidence, including boresight
uncertainties). This is within 0.4 arcsec of the initial XRT position,
and 2.0 arcmin of the refined BAT position (Fenimore et al., GCN 5660).
The XRT light curve from the first orbit shows a giant flare from
T+410s to T+1180s, which peaks at a count rate of ~70 count s^-1 at
T+535s (where T is the trigger time). This flare is also seen in BAT
data (Palmer et al., GCN 5662).
The average Windowed Timing mode spectrum during the flare (from
T+476s to T+691s; count rate equal to 36.7 count s^-1) can be
described by an absorbed power-law, with a column density of
1.85+/-0.15 e21 cm^-2 and a photon index of 1.86+/-0.05. The 0.3-10.0
keV observed (unabsorbed) flux during this interval is 1.61E-09
(2.15E-09) ergs cm^-2 s^-1.
The underlying non-flare emission is weak (0.07 count s^-1), and can
be fit with a power-law of photon index 2.3+1.4-0.8 and an
unconstrained column density less than 3.6e21 cm^-2. The 0.3-10.0 keV
observed (unabsorbed) flux is 3.3E-12 (5.3E-12) ergs cm^-2 s^-1
The Galactic column in the direction of the source is 3.6e20 cm^-2.
We have insufficient data at this time to predict a later
time X-ray decay slope and flux.
This circular is an official product of the Swift-XRT Team.
GCN Circular 5662
Subject
GRB 060929, Swift-BAT further refined analysis - late-time flare
Date
2006-09-30T02:20:04Z (20 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
D. Palmer (LANL), G. Sato (GSFC/ISAS), S. D. Barthelmy (GSFC),
T. Sakamoto (GSFC/ORAU), C. Markwardt (USFC/UMd), N. Gehrels (GSFC)
on behalf of the Swift-BAT team:
We have received additional data beyond that used for GCN Circ 5660
(Fenimore, et al) now out to T+1000 sec. We note that there is
highly significant emmission in the mask-weighted light curve starting
at T+400 sec and ending at T+600 sec. This emission is much softer
than the initial emission at T_zero.
Given the spectral signiture of the initial T_zero emission and
that there are no known sources at this location (Galactic or extra-Galactic),
we still strongly believe that this event is a GRB and not some other
non-GRB astrophysical source. We therefore conclude that this late-time
emission is a flare.
GCN Circular 5661
Subject
GRB 060929: TNG K-band observations
Date
2006-09-30T01:01:07Z (20 years ago)
From
Stefano Covino at Brera Astronomical Observatory <stefano.covino@poste.it>
S. Covino (INAF/OAB), A. de Ugarte Postigo (IAA-CSIC), N. Pinilla
(TNG), J. Licandro (ING-IAC), on behalf of the CIBO collaboration,
report:
We have observed the field of GRB 060929 (Markwardt et al., GCN 5624)
with TNG+NICS in the K band from Sep 29, 2006 22:18 UT to 22:33 UT.
No sources down to approximately K=19 (3-sigma u.l.) are present in
the XRT error circle.
We acknowledge the excellent support by the TNG staff.
This message is citable.
GCN Circular 5660
Subject
GRB 060929, Swift-BAT refined analysis
Date
2006-09-30T00:11:46Z (20 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
E. Fenimore (LANL), L. Barbier (GSFC), S. D. Barthelmy (GSFC),
J. Cummings (GSFC/UMBC), N. Gehrels (GSFC), D. Hullinger (BYU-Idaho),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), D. Palmer (LANL),
A. Parsons (GSFC), T. Sakamoto (GSFC/ORAU), G. Sato (GSFC/ISAS),
M. Stamatikos (GSFC/ORAU), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Using the data set from T-240 to T+321 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 060929 (trigger #231702)
(Markwardt, et al., GCN Circ. 5654). The BAT ground-calculated position
is RA,Dec = 263.158, 29.846 deg {17h 32m 37.9s, 29d 50' 44.3"} (J2000)
+- 1.9 arcmin, (radius, sys+stat, 90% containment). The partial coding was 84%.
The mask-weighted lightcurve shows a roughly triangular shaped peak
starting at T-5 sec, peaking at T+3 sec, and ending at T+9 sec.
T90 (15-350 keV) is 12.4 +- 0.2 sec (estimated error including systematics).
The time-averaged spectrum from T-5.5 to T+9.0 is best fit by a simple
power-law model. The power law index of the time-averaged spectrum
is 1.50 +- 0.25. The fluence in the 15-150 keV band is 2.8 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+2.69 sec in the 15-150 keV
band is 0.4 +- 0.1 ph/cm2/sec. All the quoted errors are at the 90%
confidence level.
GCN Circular 5659
Subject
GRB060929: Optical limit
Date
2006-09-29T23:38:18Z (20 years ago)
From
Graziella Pizzichini at IASF/CNR,Bologna <pizzichini@iasfbo.inaf.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"), S. Galleti, S. Bernabei (INAF
Bologna) and G. Pizzichini (INAF/IASF Bologna) report:
Using the 152 cm Loiano telescope equipped with the BFOSC
camera system, we obtained two 10 min. Rc-band images of
the field of GRB060929 (Markwardt et al., GCN 5654) starting
at Sept. 29.869 and 29. 878 respectively, seeing 2.6 arcsec.
In our co-added images we do not detect any new source
inside the XRT error circle. Star 1198-0273615 in the NOMAD catalog,
whose magnitude is 20.5, is detected at the 3 sigma level.
GCN Circular 5658
Subject
GRB 060929: BART observation
Date
2006-09-29T23:01:48Z (20 years ago)
From
Petr Kubanek at AIO <petr@lascaux.asu.cas.cz>
M. Nekola, F. Munz, J. Strobl (ASu AV CR Ondrejov), A. de Ugarte Postigo
(IAA-CSIC Granada) & P.Kubanek (ASu AV CR Ondrejov & ISDC Versoix) on
behalf of a larger collaboration reports:
BART 25 cm telescope, located at Ondrejov, Czech Republic, observed
position of the SWIFT error box for GRB 060929 (Markwardt et al. GCN
5654) starting at 19:59:12 UT (T + 2 min 39 sec). We did not detect any
new source down to R ~ 16.5 mag on first 20 sec image, as well as on
combination of first three 20 sec images with mean time 2 min 49 sec
down to R ~ 17 mag. Observation was stopped after 20 minutes due to
approaching rain.
This message is quotable
GCN Circular 5657
Subject
GRB 060929: MASTER-VWF-Kislovodsk observations
Date
2006-09-29T21:18:30Z (20 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, E.Gorbovskoy,D.Kuvshinov,
N.Tyurina, P.Gritsyk
Sternberg Astronomical Institute, Moscow Union 'Optic'
I.Golubov
Kislovodsk Solar Station of the Pulkovo observatory
"MASTER Very Wide Filed Camera located at Kislovodsk Solar Station
(http://observ.pereplet.ru, D=70 mm, 400 square degrees) has moved to the
Swift-BAT trigger 231702 and
it has taken a series of 5s exposures starting 39 s after the Notice Time
at 19:57:18 UT (42s
after the GRB). The weather is not very good.
No new object has been found within the Swift-BAT error box.
The limiting magnitude is 12.0m (unfiltered) for single exposures
and 12.8m for the sum of 20 images.
The message may be cited.
mailto: lipunov@sai.msu.ru
GCN Circular 5656
Subject
GRB 060929: BOOTES-IR & OSN observations
Date
2006-09-29T21:10:24Z (20 years ago)
From
Antonio Deugarte at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (IAA-CSIC Granada),
V. Casanova (IAA-CSIC Granada),
P. Kubanek (ASU AV CR ndrejov & ISDC Versoix) &
A. Castro-Tirado (IAA-CSIC Granada)
on behalf of a larger collaboration report:
"The 0.6m BOOTES-IR and 1.5m telescopes, located at IAA-CSIC
Observatorio de Sierra Nevada in Granada (Spain), observed the
SWIFT error box for GRB 060929 (Markwardt et al. GCN 5654)
starting at 20:17 UT (21 minutes after the burst) in R and I-bands.
We do not detect any optical counterpart down to the DSS2 limit.
Further analysis is ongoing.
This message is quotable."
[GCN OPS NOTE(29sep06): Per author's request, VC was addd to the author list.]
GCN Circular 5655
Subject
Liverpool Telescope observations of GRB 060929
Date
2006-09-29T21:08:38Z (20 years ago)
From
David Bersier at Liverpool John Moores U <dfb@astro.livjm.ac.uk>
D. Bersier, A. Gomboc, A. Melandri, C. Mundell (Liverpool JMU),
E. Rol (Leicester) report on behalf of a larger collaboration
We imaged the field of GRB 060929 (Swift trigger 231702) with
the 2m robotic Liverpool Telescope (La Palma), starting at 20:17 UT.
Inside the XRT error circle we do not detect any new source down
to a magnitude R~20. Further analysis is in progress.
GCN Circular 5654
Subject
GRB 060929: Swift detection of a burst
Date
2006-09-29T20:36:10Z (20 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
C. B. Markwardt (GSFC/UMD), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
J. R. Cummings (NASA/UMBC), N. Gehrels (NASA/GSFC),
S. D. Hunsberger (PSU), J. A. Kennea (PSU), K. L. Page (U Leicester),
D. M. Palmer (LANL), P. Romano (INAF-OAB), T. Sakamoto (NASA/ORAU),
G. Sato (GSFC/ISAS), P. Schady (MSSL-UCL) and
M. Stamatikos (NASA/ORAU) report on behalf of the Swift Team:
At 19:55:01UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 060929 (trigger=231702). Swift slewed immediately to the burst.
The on-board location (obtained from a Lightcurve SERS message) is RA,Dec (J2000)
263.164,+29.815 {17h32m39s, 29d48m54s}. Because of a telemetry gap covering the
first ~50 sec of the TDRSS messages, we can say nothing about the lightcurve until
the full data set is downlinked.
The XRT began taking data at 19:56:33 UT, 92 seconds after the BAT trigger.
The XRT on-board centroid algorithm did not find a source in the image,
however analysis of prompt downlinked data reveals a faint, uncatalogued
point source at the following location:
RA(J2000) = 17h 32m 29.0s
Dec(J2000) = +29d 50m 08.5s
with an estimated uncertainty of 7.3 arcseconds radius (90% containment).
This source lies 154 arcseconds from the BAT position.
At this time due to the telemetry gap, only a raw UVOT finding chart image (no sky
coordinates) obtained with the white light filter is available. We have attempted
to perform pattern matching with the DSS and no obvious afterglow candidate is
seen.