GRB 111209A
GCN Circular 12632
Subject
GRB 111209A: Swift detection of a long burst with an optical counterpart
Date
2011-12-09T07:42:40Z (14 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
E. A. Hoversten (PSU), P. A. Evans (U Leicester),
C. Guidorzi (U Ferrara), A. Y. Lien (NASA/GSFC/ORAU),
C. Pagani (U Leicester), K. L. Page (U Leicester),
D. M. Palmer (LANL), B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU),
M. C. Stroh (PSU), G. Tagliaferri (INAF-OAB) and B.-B. Zhang (PSU)
report on behalf of the Swift Team:
At 07:12:08 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 111209A (trigger=509336). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 14.360, -46.788 which is
RA(J2000) = 00h 57m 26s
Dec(J2000) = -46d 47' 17"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). After the original 320 second long image
trigger, the source caused a second trigger (#509337) over the
64 second time interval starting at T+424s, at much higher intensity.
The XRT began observing the field at 07:19:07.2 UT, 418.9 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 14.3462, -46.8005 which is equivalent to:
RA(J2000) = 00h 57m 23.08s
Dec(J2000) = -46d 48' 01.7"
with an uncertainty of 4.7 arcseconds (radius, 90% containment). This
location is 56 arcseconds from the BAT onboard position, within the BAT
error circle. No event data are yet available to determine the column
density using X-ray spectroscopy.
The initial flux in the 2.5 s image was 1.20e-08 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White
filter starting 427 seconds after the BAT trigger. There is a
candidate afterglow in the rapidly available 2.7'x2.7' sub-image at
approximately the same position as the XRT source with a magnitude of
18.1. No correction has been made for the expected extinction
corresponding to E(B-V) of 0.02.
Burst Advocate for this burst is E. A. Hoversten (hoversten AT astro.psu.edu).
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 12633
Subject
GRB 111209A: TAROT La Silla observatory optical detection
Date
2011-12-09T07:58:01Z (14 years ago)
From
Alain Klotz at CESR-CNRS <Alain.Klotz@free.fr>
Klotz A. (CESR-OMP), Gendre B. (ASDC),
Boer M. (OHP-OAMP), Atteia J.L. (LATT-OMP) report:
We imaged the field of GRB 111209A detected by SWIFT
(trigger 509336) with the TAROT robotic
telescope (D=25cm) located at the European Southern
Observatory, La Silla observatory, Chile.
The observations started 358s after the GRB trigger.
The elevation of the field decreased from
13 degrees above horizon and weather conditions
were good.
We detected the candidate couterpart mentioned
by Hoversten et al. (GCNC 12632)
at the following position (+/- 1 arcsec):
RA(J2000.0) = 00h 57m 22.7s
DEC(J2000.0) -46d 48' 05"
OT peaked at R~16.2 about 680s after GRB.
Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.
This message may be cited.
GCN Circular 12634
Subject
GRB 111209A: REM NIR detection
Date
2011-12-09T08:05:21Z (14 years ago)
From
Stefano Covino at Brera Astronomical Observatory <stefano.covino@brera.inaf.it>
D. Fugazza, S. Covino (INAF/OAB), E. Palazzi (INAF/IASF-Bo), L.A. Antonelli (INAF/Rome),
on behalf of a larger collaboration, report:
The robotic 60-cm REM telescope located at La Silla (Chile) observed automatically
the field of GRB 111209A (Hoversten et al. GCN 12632) with the ROSS optical
and REMIR near-infrared cameras in imaging mode.
Observations started about 30 s after the Swift alert (about 5 min after the reported burst time)
when the field was only 13 deg on the local horizon.
Summing H band images from 7 to 13 min after the burst a weak counterpart is visible
at coordinates RA=00:57:22.78 DEC=-46:48:04.2 (error approximately 0.5 arcsec on both axes)
and with magnitude H = 14.7 +- 0.2, calibrated against the 2MASS catalogue.
The source is coincident with the optical counterpart reported by Klotz et al. (GCN 12633).
Further observations are in progress.
[GCN OPS NOTE(09dec11): Per author's request, LA was added to the author list.]
GCN Circular 12635
Subject
GRB 111209A: Faulkes Telescope North observations
Date
2011-12-09T10:29:53Z (14 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), A. Melandri (INAF-OAB),
S. Kobayashi, C.G. Mundell (LJMU), A. Gomboc (U. Ljubljana)
report on behalf of the LJMU GRB group:
The 2-m Faulkes Telescope North robotically followed
up Swift GRB 111209A (Hoversten et al. GCN Circ. 12632)
from 07:20:00 UT, corresponding to 7.9 minutes after the
BAT trigger time.
Within the XRT error circle we clearly detect the optical
afterglow in the i' filter reported by Klotz et al. (GCN 12633)
and Fugazza et al. (GCN 12634) with the following magnitude:
Mid time from Total Exp Filter Magnitude
trigger (s) (s)
-------------------------------------------------
697 30 i' 18.3 +- 0.2
-------------------------------------------------
Magnitude has been calibrated from I nominal
values of nearby USNOB1.0 stars.
GCN Circular 12637
Subject
GRB 111209A: TAROT La Silla observatory optical light curve analysis
Date
2011-12-09T13:59:58Z (14 years ago)
From
Alain Klotz at CESR-CNRS <Alain.Klotz@free.fr>
Klotz A. (IRAP-OMP), Gendre B. (ASDC),
Boer M. (OHP-OAMP), Atteia J.L. (IRAP-OMP) report:
We obtained an optical follow-up until 4500 seconds
after the trigger of GRB 111209A detected by SWIFT
(trigger 509336-7) using the TAROT robotic telescope
(D=25cm) located at the European Southern Observatory,
La Silla observatory, Chile.
In this GCN circular we describe the behaviour of the
optical transcient discovered by Hoversten et al.
(GCNC 12632).
From 470s to 2000s, we observe a fluctuating
optical emission at a mean level R~17.5 that reaches
sometimes R=16.6.
From 2100s to 2550s we recorded an optical flash
that reached R=15.4. This peak is followed by
a plateau R=16.3 between 2700s to 3700s.
After 3700s the flux seems begin to decrease but
the low elevation 5 degrees above horizon does
not allow to conclude definitively about the
phase decay.
All the magnitudes are based on the assumption
that the color index of the GRB in optical
wavelengths is the same as the reference star
NOMAD1 0431-0011481 (V-R=0.34).
This message may be cited.
GCN Circular 12638
Subject
GRB111209A : planned XMM-Newton observation
Date
2011-12-09T16:05:56Z (14 years ago)
From
Bruce Gendre at ASDC <bruce.gendre@asdc.asi.it>
B. Gendre (ASDC/INAF-OAR), J.L. Atteia (IRAP-OMP), M. Bo�r (OHP-OAMP),
A. Klotz (IRAP-OMP), L. Piro (INAF-IASF-Roma), G. Stratta
(ASDC/INAF-OAR), on behaf of a larger collaboration, report :
Following the trigger of the exceptionally long and bright GRB 111209A,
we have activated a 50 ks (net) TOO on XMM-Newton starting on
2011-12-09:22:12:58 UT. We encourage any simultaneous follow-up of this
event at any wavelength.
This message can be quoted.
GCN Circular 12639
Subject
GRB 111209A: Enhanced Swift-XRT position
Date
2011-12-09T17:10:26Z (14 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 2386 s of XRT Photon Counting mode data and 3 UVOT
images for GRB 111209A, 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 = 14.34424, -46.80112 which is equivalent
to:
RA (J2000): 00h 57m 22.62s
Dec (J2000): -46d 48' 04.0"
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) and Evans
et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the
Swift-XRT team.
GCN Circular 12640
Subject
GRB 111209A, Swift-BAT refined analysis
Date
2011-12-09T18:58:12Z (14 years ago)
From
Takanori Sakamoto at NASA/GSFC <takanori@milkyway.gsfc.nasa.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC), T. Sakamoto (GSFC/UMBC),
G. Sato (ISAS), M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
Using the data set from the recent telemetry downlink, we report further
analysis of BAT GRB 111209A (trigger #509336 and #509337)
(Hoversten, et al., GCN Circ. 12632). The BAT ground-calculated position
using the event data of trigger #509337 (on-axis observation)
is RA, Dec = 14.350, -46.799 deg which is
RA(J2000) = 00h 57m 24.1s
Dec(J2000) = -46d 47' 57.1"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows an excess rate already around T-150 s
when the spacecraft settled to the pre-planned target (T is the BAT trigger
time of #509336, which is 07:12:08.3 UT). A gradual increase in the rate
continues up to T+850s. And then, the rate started to decay. The positive
rate is still seen at T+1400 s where the end of the event data. Further
analysis using the BAT survey data is on-going to address the duration of
this event detected by BAT.
The time-averaged spectrum from 358 to 1337 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.48 +- 0.03. The fluence in the 15-150 keV band measured during this
time interval is 3.6 +- 0.1 x 10^-05 erg/cm2. The 1-sec peak photon flux
measured from T+824 sec in the 15-150 keV band is 0.5 +- 0.1 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/509336/BA/
http://gcn.gsfc.nasa.gov/notices_s/509337/BA/
GCN Circular 12641
Subject
GRB 111209A: Swift Burst of Interest
Date
2011-12-09T19:04:03Z (14 years ago)
From
Erik Hoversten at Swift/Penn State <hoversten@astro.psu.edu>
E. A. Hoversten (PSU), D.N. Burrows (PSU), S. Campana (INAF-OAB), P.
A. Evans (U Leicester), N. Gehrels (GSFC), D. Grupe (PSU), M. H.
Siegel (PSU), report on behalf of the Swift team:
We report an update on Swift observations of the unusual event GRB
111209A. BAT triggered twice and is saw extended duration emission
from this event. It peaked at 900s and decreased in flux after 1100s,
but continued well beyond that to >10ks.
We have analyzed 11.9 ks of XRT data for GRB 111209A (Hoversten et
al. GCN Circ. 12632), from 425 s to 25.16 ks after the BAT trigger.
The data contain 9.4 ks in Windowed Timing (WT) mode data and the
remainder in photon counting (pc) mode.
The light curve is highly complicated showing multiple flares. The
afterglow is very bright and XRT remained in WT mode through 4 orbits
(20ks after the trigger). The light curve after the fourth orbit
suggests a sharp drop in the count rate from about 14 counts s^-1 at
the end of the forth orbit to 5 counts s^-1 at the beginning of
the fifth orbit. The data of the 5th orbit were entirely taken in
photon counting (pc) mode and the decay slope steepens significantly.
The Swift/UVOT began settled observations of the field of GRB 111209A
427 s after the BAT trigger. The afterglow is clearly detected in all
seven UVOT filters. We find a refined UVOT position of
RA (J2000) 00:57:22.63 = 14.34429 (deg)
Dec (J2000) -46:48:03.8 = -46.80106 (deg)
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence,
statistical + systematic). This position is 0.25 arcseconds from the
UVOT-enhanced XRT position, which is within the errors.
The white, v, and b filter show a fading source over the first orbit,
however at the end of the first orbit the white magnitude increases
abruptly by 0.6 magnitudes corresponding with a significant flare in
the X-rays. The v, b, u, uvw1, and uvm2 magnitudes show a
rebrightening between 5.4 and 7 ks after the burst of 0.3 to 1.1
magnitudes.
The data from all three instrument is similar is several ways to GRB
060218, the long event associated with SN2006aj, and to GRB 101225A,
the Christmas burst. The detection in all UVOT filters implies a low
redshift of z < 1.6. We note that at 18 ks after the burst the source
is still at 18th magnitude in the white filter which is extremely
unusual. Given the rare behavior exhibited by GRB 111209A we advocate
for additional observations at all wavelengths.
GCN Circular 12642
Subject
GRB 111209A: Swift UVOT refined analysis
Date
2011-12-09T19:22:04Z (14 years ago)
From
Erik Hoversten at Swift/Penn State <hoversten@astro.psu.edu>
E. A. Hoversten (PSU) and M. H. Siegel (PSU), report on behalf of the
UVOT team:
The Swift/UVOT began settled observations of the field of GRB 111209A
427 s after the BAT trigger (Hoversten et al., GCN Circ. 12632). The
afterglow is clearly detected in all seven UVOT filters. We find a
refined UVOT position of
RA (J2000) 00:57:22.63 = 14.34429 (deg)
Dec (J2000) -46:48:03.8 = -46.80106 (deg)
with an estimated uncertainty of 0.5 arcsec (radius, 90% confidence,
statistical + systematic). This position is 0.25 arcseconds from the
UVOT-enhanced XRT position (Evans et al., GCN Circ. 12639), which is
within the errors.
The white, v, and b filters show a fading source over the first orbit,
however at the end of the first orbit the white magnitude increases
abruptly by 0.6 magnitudes corresponding with a significant flare in
the X-rays. The v, b, u, uvw1, and uvm2 magnitudes show a
rebrightening between 5.4 and 7 ks after the burst of 0.3 to 1.1
magnitudes. Preliminary magnitudes using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag Err
white_FC 427 577 147 17.94 0.04
white 855 1005 147 17.73 0.04
white 1856 1876 19 18.01 0.11
white 2030 2050 19 17.40 0.08
v 584 603 19 17.25 0.24
b 1134 1154 19 18.16 0.21
u 6064 6264 196 18.11 0.09
w1 633 653 19 17.16 0.24
m2 5653 5853 196 18.23 0.17
w2 5244 5443 196 17.96 0.12
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.02 in the direction of
the burst (Schlegel et al. 1998).
The data from all three instrument is similar is several ways to GRB
060218, the long event associated with SN2006aj, and to GRB 101225A,
the Christmas burst. The detection in all UVOT filters implies a low
redshift of z < 1.6. We note that at 18 ks after the burst the source
is still at 18th magnitude in the white filter which is extremely
unusual. Given the rare behavior exhibited by GRB 111209A we advocate
for additional observations at all wavelengths.
GCN Circular 12643
Subject
GRB 111209A: Swift-XRT refined Analysis
Date
2011-12-09T19:34:18Z (14 years ago)
From
Dirk Grupe at PSU/Swift-XRT <dxg35@psu.edu>
D. Grupe (PSU) and E. A. Hoversten (PSU) reports on behalf of the
Swift-XRT team:
We have analyzed 11 ks of XRT data for GRB 111209A (Hoversten et al.
GCN Circ. 12632), from 425 s to 25.2 ks after the BAT trigger. The
data comprise 9.4 ks in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Evans et al. (GCN. Circ 12639).
The light curve can be modeled with a series of power-law decays. The
light curve initially rises, with an index alpha=-0.21 (+/-0.04). At
T+864 s it breaks to an alpha of 7.3 (+0.7, -2.6). The light curve
breaks again at T+899 s to a decay with alpha=0.679 (+0.012, -0.087),
and again at T+5807 s s to alpha=1.179 (+/-0.016), before a final
break at T+19.4 ks s after which the decay index is 6.3 (+1.2, -0.4).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.333 (+/-0.012). The
best-fitting absorption column is 1.38 (+/-0.04) x 10^21 cm^-2, in
excess of the Galactic value of 1.5 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 1.83 (+0.17, -0.16)
and a best-fitting absorption column of 1.3 (+0.5, -0.4) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 4.1 x 10^-11 (5.2 x 10^-11) erg cm^-2
count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 1.3 (+0.5, -0.4) x 10^21 cm^-2
Galactic foreground: 1.5 x 10^20 cm^-2
Excess significance: 4.4 sigma
Photon index: 1.83 (+0.17, -0.16)
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00509336.
This circular is an official product of the Swift-XRT team.
GCN Circular 12645
Subject
GRB 111209A: PROMPT optical observations of early afterglow
Date
2011-12-09T22:54:13Z (14 years ago)
From
Melissa Nysewander at UNC-Chapel Hill <mnysewan@unc.edu>
M. Nysewander, J. Haislip, A. LaCluyze, K. Ivarsen, D. Reichart, J. Moore, A. Trotter, R. Egger, A. Foster, A. Oza, T. Cromartie, E. Speckhard, and J. A. Crain report:
Skynet observed the field of GRB 111209A with the PROMPT telescopes located at CTIO in Chile. Observations began in VRI at 378 sec (34 sec after the alert) and lasted for 13.2 min before the source set below PROMPT's elevation constraints.
We detect the fading afterglow discovered by Hoversten et al. (GCN 12632). Preliminary calibration to USNO B1.0 catalog stars yields the follow initial detections:
Start Time t - t0 Exp Telescope Filter Mag Err
07:18:28 380s 40s Prompt5 I 18.0 0.20
07:18:31 383s 40s Prompt4 R 18.3 0.30
GCN Circular 12646
Subject
GRB 111209A optical limit by "Pi of the Sky"
Date
2011-12-09T23:59:27Z (14 years ago)
From
Marcin Sokolowski at Soltan Inst. Nuc Studies,Warsaw <marcin.sokolowski@fuw.edu.pl>
M.Sokolowski,A.Majcher,T.Batsch,A.Majczyna,K.Nawrocki,G.Wrochna (NCNR,Swierk),
M.Cwiok,W.Dominik,L.W.Piotrowski,A.F.Zarnecki (University of Warsaw),
K.Malek,L.Mankiewicz,R.Opiela,M.Siudek,V.Repei (CFT PAN),
G.Kasprowicz,M.Zaremba (Warsaw University of Technology),
from the "Pi of the Sky" collaboration (http://grb.fuw.edu.pl).
The wide field "Pi of the Sky South" apparatus, installed in the private
observatory of Alain Maury in San Pedro de Atacama
(http://grb.fuw.edu.pl/pi/index.html#spda_site.htm) observed the position
of GRB 111209A ( SWIFT trigger #590336 ).
Three 10s images of this field have been taken at 01:59:03 - 01:59:51 UT
( 5 hours 13 min 5 sec before the first BAT alert ). No new object can be
seen within the error box and the limit on 3 coadded images is 12.7 mag.
After receiving the trigger from SWIFT, the field was observed 480 seconds
after the GRB. The field has been observed in time period from 7:20:09 to
7:44:25 UT, no new object brighter than 10.2 mag was observed on 10s
images. The limit on 20 coadded images is 10.7 mag.
Limits are based on the reference star magnitudo in V filter.
We acknowladge great support received from Alain Maury at SPdA Observatory.
GCN Circular 12647
Subject
GRB 111209A: GROND Afterglow observations
Date
2011-12-10T05:52:24Z (14 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
D. A. Kann, S. Klose (TLS Tautenburg), T. Kruehler (DARK/NBI) and J.
Greiner, (MPE Garching) report on behalf of the GROND team:
We observed the field of the "Swift Burst of Interest" GRB 111209A (Swift
trigger 509336 and 509337; Hoversten et al., GCN #12612) simultaneously in
g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP, 120, 405) mounted at
the 2.2 m ESO/MPG telescope at La Silla Observatory (Chile). Observations
started on December 10, 2011, at 00:56 UT, 0.74 days after the GRB
trigger, during twilight. They were performed at an average seeing of 0".9
and at an airmass of 1.
At the position of the optical afterglow (Klotz et al., GCN #12633;
Fugazza et al., GCN #12634; Guidorzi et al., GCN #12635; Hoversten &
Siegel, GCN #12642; Nysewander et al., GCN #12645), we clearly detect a
source in single 35 second integrations in g'r'i'z'.
Based on co-added images of 142 s integration time in g'r'i'z' and 240 s
in JHK, centered 0.74144 days after the trigger, the following magnitudes
(AB magnitude system) have been derived:
g' = 20.3 +/- 0.1
r' = 20.1 +/- 0.1
i' = 19.9 +/- 0.1
z' = 19.8 +/- 0.1
J = 19.3 +/ 0.2
H = 19.0 +/- 0.2
K = 18.6 +/- 0.4
The spectral slope is found to be beta ~0.8, which is typical for a GRB
afterglow, and dissimilar to thermally dominated emission.
Magnitudes were calibrated against an SDSS standard field in g'r'i'z' and
2MASS field stars in JHK.
Observations have continued at high cadence under excellent conditions. We
note these observations are contemporaneous to the planned XMM-Newton
observation (Gendre et al., GCN #12638).
GCN Circular 12648
Subject
GRB 111209A: VLT/X-shooter redshift
Date
2011-12-10T06:05:55Z (14 years ago)
From
Paul Vreeswijk at U of Iceland <pmv@raunvis.hi.is>
Paul Vreeswijk (U. Iceland), Johan Fynbo (DARK), Andrea Melandri
(INAF-OAB) report on behalf of the X-shooter GTO GRB afterglow
collaboration:
The afterglow of Swift GRB 111209A (Hoversten et al., GCN 12632, Klotz
et al., GCN 12633, Fugazza et al., GCN 12634) was observed with the
X-shooter spectrograph mounted at the Kueyen unit of the VLT on Cerro
Paranal, Chile. Starting around 1 UT on 10 December 2011 (0.75 days
after the burst), a series of four spectra of 1200s each were secured,
covering the approximate wavelength range 0.3-2.5 micron. The slit
width was set to 1", resulting in a resolving power range of
4500-7500.
Preliminary reduction of the ultraviolet and visual parts of the
spectra shows a smooth continuum with several absorption features that
we can identify with resonance absorption lines of FeII, MgII, MgI,
CaII H and K at a redshift of z=0.677; this is the likely redshift of
GRB 111209A.
We acknowledge the excellent support from the Paranal Observatory staff,
in particular Willem-Jan de Wit, Dimitri Gadotti and Marcelo Lopez.
We are also very grateful for the flexibility and willingness of the
VLT-I visiting astronomer, Stefan Kraus, to shift his observations
to the end of the night, which have made these X-shooter observations possible.
[GCN OPS NOTE(10dec11): Per author's request, the last paragraph was expanded.]
GCN Circular 12649
Subject
GRB 111209A: IRTF NIR Imaging/Spectroscopy
Date
2011-12-10T11:59:38Z (14 years ago)
From
Myungshin Im at Seoul Nat U <mim@astro.snu.ac.kr>
Myungshin Im, Hyunsung Jun, and Dohyeong Kim (CEOU/Seoul National Univ)
We observed GRB 111209A (Hoversten et al., GCN 12632) using SpeX
on IRTF. The observation started at 12-09-07:42:13 UT, or about 0.5 hrs
after the BAT alert. H-band images were taken using a guider camera
revealing a bright NIR counterpart with its flux at H~12 mag.
Note that calibration is done by an observation of a standard star
next night and needs a further refinement.
NIR spectra were taken at 0.8-2.5 micron with R=750 for
about 24 min, starting at ~35 min after the BAT alert,
showing good S/N but no obvious features in raw spectra.
Analysis of the spectral/imaging data is onging.
GCN Circular 12656
Subject
GRB 111209A: Rebrightening seen by GROND
Date
2011-12-10T23:45:21Z (14 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
D. A. Kann (TLS Tautenburg), and J. Greiner, (MPE Garching)
report on behalf of the GROND team:
We have analyzed the J-band observations (Kann et al., GCN #12647)
obtained with GROND over a total of five hours (0.74 to 0.93 days after
the trigger) of GRB 111209A (Hoversten et al., GCN #12632). Astrometry and
calibration were obtained against the 2MASS catalog.
We find the afterglow experiences a strong rise during our observations,
rising from J ~ 19.3 to J ~ 18.8 (AB Magnitudes). The slope of the rise is
alpha < -2 (assuming F(t) propto t^-alpha). This behavior may be due to a
strong energy injection.
Highly variable behavior in the first hours has already been reported by
Klotz et al. (GCN #12637) and Hoversten & Siegel (GCN #12642).
Dense photometric follow-up is strongly encouraged.
GCN Circular 12663
Subject
Konus-Wind observation of GRB 111209A
Date
2011-12-11T14:10:38Z (14 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team report:
The exceptionally long GRB 111209A (Swift-BAT trigger #509336: Hoversten
et al., GCN 12632; Palmer et al., GCN 12640) was detected by
Konus-Wind in the waiting mode.
The burst light curve shows the main multipeaked episode of emission
started at ~T0(BAT)-1900 s and lasted until ~T0(BAT)+4400 s (the
duration is ~6300 s; T0(BAT)=25928 s UT (07:12:08)). There is also a
weaker broad pulse of emission seen before the main pulse from
~T0(BAT)-5400 s to ~T0(BAT)-2600 s and a hint of an additional episode
of emission after the main pulse from ~T0(BAT)+5000 s to ~T0(BAT)+10000
s. Both these episodes might be related to GRB 111209A (they were
detected by the same KW detector, and the KW ecliptic latitude responses
for them are consistent with the common origin with the main episode).
The most intense peak in the Konus-Wind light curve, (which started at
~T0+1740 s, peaked at ~T0+2040 s, and ended at ~T0+2300 s), corresponds
to a significant raise in the XRT lc
(http://www.swift.ac.uk/xrt_curves/00509336/ - Grupe & Hoversten GCN
12643) and a bright optical flash (Klotz et al., GCN 12637).
As observed by Konus-Wind, the burst (the main episode) had a fluence of
(4.86 � 0.61)x10^-4 erg/cm2 (in the 20 - 1400 keV energy range).
Modeling the KW 3-channel time-integrated spectrum (from T0-1890 s to
T0+4400 s) by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -1.31 � 0.09, and Ep = 310 � 53 keV.
Assuming z = 0.677 (Vreeswijk, Fynbo, & Melandri GCN 12648) and a
standard cosmology model with H_0 = 71 km/s/Mpc, Omega_M = 0.27,
Omega_Lambda = 0.73, the isotropic energy release, E_iso, is (5.82 �
0.73)x10^53 erg, and Ep_rest is 520 � 89 keV.
Thus, the prompt gamma-ray emission properties of this GRB: fluence, Ep,
and E_iso are similar to those observed in other long energetic GRBs.
The only exceptional feature of the prompt gamma-ray emission is the
huge duration.
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.
The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB111209A/
GCN Circular 12664
Subject
GRB 111209A - ATCA 34GHz upper limit
Date
2011-12-12T03:58:18Z (14 years ago)
From
Paul Hancock at U of Sydney <hancock@physics.usyd.edu.au>
Paul J. Hancock, Tara Murphy, Bryan Gaensler (U of Sydney), Ashley
Zauderer (Harvard)
On the 11th December 04:44-05:50UT (T=+1.9days) we observed GRB 111209A
(GCN12632) with the Australia Telescope Compact Array (ATCA) at 34GHz.
We do not detect any radio emission consistent with the GRB optical
position (GCN12642). We place a 3sigma upper limit of 132uJy on the flux
of the afterglow. Further observations are planned.
We thank the staff of the ATCA for their help in organising these
observations.
GCN Circular 12684
Subject
GRB 111209A: RAPTOR Limits Before and During the Gamma-ray Emitting Interval
Date
2011-12-15T17:32:20Z (13 years ago)
From
James Wren at LANL <jwren@nis.lanl.gov>
J. Wren, W. T. Vestrand, P. Wozniak, and H. Davis
of Los Alamos National Laboratory report:
The RAPTOR wide-field optical monitors were observing the location of
GRB 111209A (Hoversten et al., GCN 12632) during the gamma-ray emitting
interval as seen by the Swift BAT (Palmer et al., GCN 12640). Our
system acquired 10 s exposures at 20 s intervals during the entire
emission period. We have analyzed the the 77 images taken between
T-150 and T+1400 and we do not detect the counterpart to a typical
3-sigma limiting magnitude of 10.3. Our unfiltered images were
calibrated to the Tycho-2 V-band.
GCN Circular 12804
Subject
GRB111209A: ATCA detection at 5.5, 9, and 18GHz
Date
2012-01-04T05:37:27Z (13 years ago)
From
Paul Hancock at U of Sydney <hancock@physics.usyd.edu.au>
Paul J. Hancock, Tara Murphy, Bryan Gaensler (U of Sydney), Ashley
Zauderer (Harvard)
Following our 34GHz non-detection (GCN12664) we observed GRB 111209A
(GCN12632) with the Australia Telescope Compact Array (ATCA) at 5.5,
9, and 18GHz on the 14th of December (T=+5.1days). The mean observing
time was 11:12UT at 5.5 and 9GHz, and 11:47UT at 18GHz. We easily detect
the GRB at each frequency as listed below:
Freq Flux
5.5GHz 0.85+/-0.04mJy
9GHz 0.97+/-0.06mJy
18GHz 3.23+/-0.05mJy
We thank the staff of the ATCA for their help in organising these observations.