GRB 050603
GCN Circular 3509
Subject
Swift/BAT Detection of GRB050603
Date
2005-06-03T08:11:03Z (20 years ago)
From
David Palmer at LANL <palmer@nis.lanl.gov>
A. Retter (PSU), A. Parsons, N. Gehrels (GSFC), C. Gronwall (PSU),
C. B. Markwardt (GSFC/UMD), D. Palmer (LANL)
on behalf of the Swift Team report:
At 06:29:05 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB050603 (trigger=131560). The BAT on-board calculated
location is RA,Dec 39.978 (+02h 39m 55s), -25.183 (-25d 10' 57")
(J2000) with an uncertainty of 4 arcmin (radius, 3-sigma, including
estimated systematic uncertainty). The peak rate was
22,000 counts/sec in 0.512 sec in the 50 - 350 keV band.
The Swift spacecraft did not slew because automated slewing was not
enabled due to engineering tests. XRT and UVOT observations will be
performed after the analysis of the ground data. This burst is near
the edge of the FOV (~8% coding) and so it is brighter than indicated
by the nominal peak count rate.
No light curves will be available until the next Malindi ground contact
data is received and analyzed. However, during the approximately 7
seconds of image processing, no subsequent interval was found with a more
significant rate increase than the initial 0.512 s trigger (although
further emission at lower levels is not precluded by the data available
at this time.) Thus preliminary indications suggest that this might be
a bright short-hard burst.
GCN Circular 3510
Subject
GRB 050603: INTEGRAL shows it is not a short GRB
Date
2005-06-03T08:56:11Z (20 years ago)
From
Diego Gotz at IASF-CNR <diego@mi.iasf.cnr.it>
D. Gotz and S. Mereghetti (IASF, Milano) on behlaf of the IBAS
Localization Team report:
GRB 050603 (Retter et al., GCN 3509) has been detected also by the IBIS
instrument on board INTEGRAL in the 40-300 keV energy band. Being outside
of the field of view of the instrument, this burst cannot be localized.
The burst starts at 2005-06-03T06:29:03 UT and has a multipeaked light
curve, showing at least 3 distinct peaks, with the last one being the
brightest. The GRB lasts 10 s, so it does not belog to the short class.
This message can be cited.
GCN Circular 3511
Subject
GRB 050603: Afterglow Identification from LCO
Date
2005-06-03T11:01:08Z (20 years ago)
From
Edo Berger at Carnegie Obs <eberger@ociw.edu>
Edo Berger and Andy McWilliam (Carnegie Observatories) report:
"On 2005, June 3.412 UT (3.4 hrs after the burst) we imaged the BAT error
circle of GRB 050603 (GCN 3509) with the du Pont 100-inch telescope at Las
Campanas Observatory in the R-band. Within the 4' radius error circle we
find a single bright source (R~16.5 mag) which is not present in the DSS
at coordinates (J2000):
RA = 02:39:57
DEC=-25:10:54
with an uncertainty of about 0.5" in each coordinate. At the present we
do have information about variability."
GCN Circular 3512
Subject
GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
Date
2005-06-03T11:38:08Z (20 years ago)
From
David Palmer at LANL <palmer@nis.lanl.gov>
E. Fenimore (LANL), L. Angelini (GSFC-JHU)L. Barbier (GSFC),
S. Barthelmy (GSFC), J. Cummings (GSFC/NRC), N. Gehrels (GSFC),
J. Greiner (MPE), D. Hullinger (UMD), H. Krimm (GSFC/USRA),
C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
A. Retter (PSU) T. Sakamoto (GSFC/NRC), G. Sato (ISAS),
M. Suzuki (Saitama), J. Tueller (GSFC)
on behalf of the Swift/BAT team:
At 06:29:05.2 UT, Swift-BAT detected GRB 050603 (trigger=131560)
(GCN Circ 3509, Retter et al.). The refined BAT ground position
is (RA,Dec) = 39.982,-25.195, [deg; J2000] {02:39:56; -25:11:41}
(~1 arcminute statistical and systematic error radius,
95% containment). This is about 45 arcseconds from the
on-board derived position. This source was near the edge of
the field of view, 41 degrees from the boresight in the
short direction, directly illuminating only 9% of the
detector array.
The mask-weighted lightcurve of the burst shows three
fast-rise-exponential-decay (FRED) spikes, peaking at
T-2.7, T-0.85 and T+0.15 with each spike having a width
of ~0.6 s (FWHM). The third spike is ~3x the height of each of
the first two spikes and produced the original image detection.
Additional tail emission continues to decay after the third
spike, extending to T+10.
The photon index of the time-averaged spectrum is well-fit
over the 15-350 keV energy band by a power law of index
1.22 +/- 0.06 with a normalization at 50 keV of
(2.96 +/- 0.10) x 10^-2 photons/s/cm^2/keV. The fluence
in the 15-350 keV band is 1.30 x 10^-5 erg/cm^2. The peak
flux is 31.8+/1.7 photons/cm^2/s for the 1 second interval
starting at T-0.18 s.
Due to the current engineering mode of the spacecraft,
XRT and UVOT observations will be delayed until a
Target Of Opportunity pointing is manually commanded.
GCN Circular 3513
Subject
GRB050603: Radio Detection
Date
2005-06-03T19:32:18Z (20 years ago)
From
Patrick B. Cameron at Caltech <pbc@astro.caltech.edu>
P. B. Cameron (Caltech) reports on behalf of the
Caltech-NRAO-Carnegie GRB Collaboration:
"We observed the field of GRB050603 (GCN#3509) using the Very Large Array
at a frequency of 8.5 GHz on June 3.62 UT. We detect a radio source with
coordinates (J2000)
Ra= 02:39:56.891
Dec= -25:10:54.6
with an uncertainty of 0.1" in each coordinate at the position of the
optical afterglow (GCN#3511)."
GCN Circular 3514
Subject
GRB 050603: Swift XRT Position
Date
2005-06-03T20:10:04Z (20 years ago)
From
Judith Racusin at PSU <racusin@astro.psu.edu>
J. L. Racusin, D. N. Burrows, J. A. Kennea, A. Retter (PSU), C. Pagani
(INAF-OAB), A. Wells (U. Leicester), N. Gehrels (NASA/GSFC) report on
behalf of the Swift XRT team:
The Swift BAT detected GRB 050603 at 06:29:05.2 UT on June 3rd 2005 (GCN
3509, Retter et al.). The Swift observatory did not slew promptly because
automated slewing was not enabled due to engineering tests. The XRT began
taking data at 17:19:27 UT, approximately 11 hours after the trigger. In
a preliminary data analysis we detect an uncataloged X-ray source located
at:
RA(J2000) = 2:39:56.6,
Dec(J2000) = -25:10:52.5
We estimate an uncertainty of 8 arcseconds radius (90% containment).
This position is 51 arcseconds from the BAT refined position reported by
Fenimore et al. (GCN 3512), 5.6 arseconds from the optical afterglow
candidate reported by Berger et al. (GCN 3511), and 4.5 arcseconds from
the radio afterglow candidate reported by Cameron et al. (GCN 3513).
Observations are still underway and further ground analysis will be
performed to determine if this X-ray source is fading.
GCN Circular 3515
Subject
GRB050603, submillimetre observations
Date
2005-06-03T20:23:59Z (20 years ago)
From
Vicki Barnard at Joint Astro.Centre,Hawaii <vbarnard@jach.hawaii.edu>
V. Barnard, G. Schieven, R. Tilanus, E. Lundin (all Joint Astronomy
Centre), R. Ivison (Astronomy Technology Centre, Royal Observatory
Edinburgh) report on behalf of the JCMT afterglow collaboration:
We have observed the field of the afterglow of GRB050603 as reported in
GCN 3511 with SCUBA at the JCMT. SCUBA operates simultaneously at 450 and
850 microns and has a field of view of approximately 2.3 arcmin. In
moderate weather conditions, the initial results are:
850 micron: 2.408 +/- 1.973 mJy
450 micron: -41.97 +/- 94.988 mJy
These observations began at 20050603.738 UT and ended at 20050603.823 UT.
GCN Circular 3516
Subject
GRB050603: Fading Afterglow observed by Swift UVOT
Date
2005-06-03T21:21:19Z (20 years ago)
From
Patricia Schady at MSSL/Swift <ps@mssl.ucl.ac.uk>
P. Brown (PSU), A. Retter (PSU), P. Schady (MSSL), P. Roming (PSU), C.
Gromwall (PSU), N. Cucchiara (PSU), P. Boyd (GSFC), K. Mason (MSSL), N.
Gehrels (GSFC), on behalf of the Swift UVOT team
The Swift Ultra-Violet/Optical Telescope (UVOT) began observations of
GRB050603 on June 3, 2005 at 15:42:59 UT, ~9 hours after the initial Swift
BAT trigger (Retter et al, GCN 3509). The observations were delayed
because automated slewing was not enabled during engineering tests at the
time of the burst. A fading source is detected in the V band at the
afterglow position first reported by Berger & McWilliam (GCN 3511). The
coordinates of this source are
Ra, Dec = 02:39:56.839, -25:10:54.92
Astrometry was performed using reference stars from the GSC.
Magnitudes from the two long exposures are as follows:
Filter Magnitude Duration(s) T_start(s)
V 18.2 +/- 0.12 1298 32997
V 21.8 +/- 0.4 2103 38782
GCN Circular 3517
Subject
GRB 050603: Analysis of UVOT data
Date
2005-06-03T23:18:24Z (20 years ago)
From
Edo Berger at Carnegie Obs <eberger@ociw.edu>
E. Berger (Carnegie Observatories) reports:
"We obtained the UVOT V-band data from the Swift quick-look webpage and
performed aperture photometry on the two epochs discussed in GCN 3516.
We find that the afterglow faded by 1.3 mag between the two observations
rather than 3.6 mag as reported in GCN 3516."
This message may be cited
[GCN OPS NOTE(04jun05): Per author's request, the Subject line was corrected
from "050406" to "050603".]
GCN Circular 3518
Subject
Konus-Wind observation of GRB 050603
Date
2005-06-04T15:44:05Z (20 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and
T. Cline on behalf of the Konus-Wind team report:
The long bright multipeak GRB 050603
(Swift-BAT trigger=131560: GCN 3509, 3512)
triggered Konus-Wind at T0=23340.767 s UT (06:29:00.767).
As observed by Konus-Wind it had a duration of ~6 s,
fluence (3.41 � 0.06)10-5 erg/cm2,
peak flux on 16-ms time scale (3.2 � 0.2)10-5 erg/cm2 s
(both in the 20 keV - 3 MeV energy range).
A weak decaying tail after the last, brigtest spike
of the GRB is seen up to ~11 s after T0
(this tail was seen and repoted by Swift-BAT in GCN 3512).
The time-integrated spectrum is well fitted by a GRB (Band) model:
the low-energy photon index is alpha = -0.79 � 0.06,
the high energy photon index beta = -2.15 � 0.09,
the break energy E0 = 289 � 36 keV,
and the peak energy Ep = 349 � 28 keV.
GCN Circular 3519
Subject
GRB 050603 - XRT data analysis of the first day
Date
2005-06-05T17:25:30Z (20 years ago)
From
Dirk Grupe at PSU/Swift-XRT <grupe@astro.psu.edu>
subject: GRB 050603 - XRT data analysis of the first day
D. Grupe, A. Retter, D. Burrows, J. Kennea (PSU), and N Gehrels (GSFC), on
behalf of the Swift XRT team report:
We analyzed the XRT data of the first day of observation of the GRB
050603 (Retter
et al., GCN #3509). The observations started approximately 11 hours
after the
burst (Racusin et al., GCN #3514).
Preliminary analysis of the data obtained so far (31 ks)
give the following refined coordinates:
Ra-2000: 02h 39m 56.8s
Dec-2000: -25d 10' 59.8"
The centroiding error is 6".
This position is about 7" off the X-ray position given in Racusin et al.
(GCN
#3514) and 5" off the radio position (Cameron, GCN #3113) and the UVOT
position
given in Brown et al. (GCN #3116).
The source had a flux of 2.2e-12 ergs/s/cm2 11 hours after the burst and is
decaying with a decay slope alpha=1.78+/-0.14.
The X-ray spectrum can be fitted with a single powerlaw with an X-ray
spectral
slope beta=0.80+/-0.08. The fit is consistent with Galactic absorption
(NH=2e20
1/cm2).
This message may be cited
GCN Circular 3520
Subject
GRB 050603: Redshift
Date
2005-06-05T21:52:43Z (20 years ago)
From
Edo Berger at Carnegie Obs <eberger@ociw.edu>
Edo Berger (Carnegie Observatories) and George Becker (Caltech) report:
"We obtained a 45-min spectrum of the afterglow of GRB 050603 (GCNs 3509,
3511) with IMACS on the Magellan/Baade telescope on 2005, June 5.40 UT
(2.13 days after the burst). We find a single bright emission line at an
observed wavelength of 4645.1A, which we interpret as Lyman-alpha at a
redshift of z=2.821.
At this redshift the isotropic-equivalent gamma-ray energy is 2.3e54 erg
(using a fluence of 3.4e-5 erg/cm^2; GCN 3518). The steep fading observed
by the UVOT (GCN 3517) and XRT (GCN 3519) suggests a jet break at t~12
hours after the burst, corresponding to a jet opening angle of about 1.7
deg, and hence a beaming-corrected energy of 1.1e51 erg."
GCN Circular 3522
Subject
GRB 050603: prediction of t_break
Date
2005-06-06T12:07:23Z (20 years ago)
From
Gabriele Ghisellini at Obs.Astro. di Brera <gabriele@merate.mi.astro.it>
G. Ghirlanda, G. Ghisellini, C. Firmani, F. Tavecchio
(Oss. Astron. di Brera) report:
GRB 050603, with a redshift of 2.821 (Berger and Becker, GCN 3520),
fluence and spectral parameters as measured by Konus-Wind
(Golenetskii et al., GCN 3518), requires an achromatic break
at t = 7 +/- 3 days (after trigger) to be consistent with the
"Ghirlanda" relation between the collimation corrected
energy and Epeak. A plot can be seen at:
http://www.merate.mi.astro.it/~ghirla/deep/blink.htm .
We urge observations in order to verify this prediction.
This message may be cited.
GCN Circular 3549
Subject
CORRECTION: GRB050603 Swift UVOT Afterglow Observations
Date
2005-06-15T01:37:36Z (20 years ago)
From
Peter Brown at PSU <pbrown@astro.psu.edu>
P. Brown (PSU), A. Retter (PSU), P. Schady (MSSL), P. Boyd (GSFC),
S. T. Holland (GSFC/USRA), P. Roming (PSU), C. Gronwall (PSU),
N. Cucchiara (PSU), K. Mason (MSSL), N. Gehrels (GSFC),
on behalf of the Swift UVOT team:
The second V-filter magnitude (V=21.8 at T_start=32997) reported in
GCN 3516 for the fading afterglow of GRB050603 is incorrect. An error
in the on-board shift-and-add code resulted in an unusually large
amount of missing data for this exposure that was not correctly
recorded in the exposure information. The real exposure time for the
second exposure was adjusted to 101 s to match the actual data
contained in the image. The corrected magnitude is 18.7, meaning the
afterglow only faded by 0.5 magnitudes between the two observations
reported in GCN 3516.
In addition, we report the afterglow magnitude in later exposures.
An error-weighted powerlaw fit gives a decay index of 1.97 +/- 0.22.
The corrected and new afterglow magnitudes from UVOT are as follows:
Time (h) Mag Filter Duration (s)
9.5 18.2 +/- 0.1 V 1298
10.9 18.7 +/- 0.4 V 101
12.7 19.5 +/- 0.2 V 1772
14.4 19.3 +/- 0.2 V 2104
15.9 19.0 +/- 0.2 V 1200
17.8 19.7 +/- 0.3 V 1205
20.8 20.1 +/- 0.4 V 1948
36.1 21.1 +/- 0.4 V 10,458 (9 exposures coadded)
Time (h) is the midpoint of the exposure given in hours after the
burst trigger. The reported errors do not include a +/- 0.09 error in
the preliminary inflight zero point calibration.