J/ApJ/858/65 A VLA study of high-redshift GRBs. I. GRB140311A (Laskar+, 2018)
A VLA study of high-redshift GRBs.
I. Multiwavelength observations and modeling of GRB 140311A.
Laskar T., Berger E., Chornock R., Margutti R., Fong W.-F., Zauderer B.A.
<Astrophys. J., 858, 65-65 (2018)>
=2018ApJ...858...65L 2018ApJ...858...65L (SIMBAD/NED BibCode)
ADC_Keywords: GRB; Millimetric/submm sources; Radio lines; Photometry; Optical
Keywords: gamma-ray burst: general;
gamma-ray burst: individual: GRB 140311A
Abstract:
We present the first results from a recently concluded study of GRBs
at z≳5 with the Karl G. Jansky Very Large Array (VLA). Spanning 1 to
85.5GHz and 7 epochs from 1.5 to 82.3d, our observations of GRB140311A
are the most detailed joint radio and millimeter observations of a GRB
afterglow at z≳5 to date. In conjunction with optical/near-IR and
X-ray data, the observations can be understood in the framework of
radiation from a single blast wave shock with energy EK,iso∼8.5x1053erg
expanding into a constant density environment with density, n0∼8cm-3.
The X-ray and radio observations require a jet break at tjet∼0.6d,
yielding an opening angle of θjet∼4° and a beaming-corrected
blast wave kinetic energy of EK∼2.2x1050erg. The results from our
radio follow-up and multiwavelength modeling lend credence to the
hypothesis that detected high-redshift GRBs may be more tightly beamed
than events at lower redshift. We do not find compelling evidence for
reverse shock emission, which may be related to fast cooling driven by
the moderately high circumburst density.
Description:
GRB 140311A was discovered by the Swift Burst Alert Telescope (BAT) on
2014 March 11 at 21:05:16 UT.
The optical afterglow, discovered by the 1m Nanshan telescope at the
Xinjiang Observatory, was subsequently observed with several other
telescopes.
Spectroscopic observations 11.3hr after the burst with the
Gemini-South 8m telescope provided a redshift of z=4.95, which was
confirmed by the Nordic Optical Telescope (NOT).
The Swift UV/Optical Telescope (UVOT) observed GRB 140311A beginning
0.11 days after the burst. Our derived upper limits are listed in
Table 2.
We further analyze i'- and r'-band acquisition images of the field
taken at Gemini-North and Gemini-South, respectively. We downloaded
the images and performed photometry in a 2.5" aperture calibrated to
SDSS. We present the results and a compilation of all other optical
observations reported in GCN circulars in Table 3.
We obtained a single epoch of optical spectroscopy of the afterglow
using the Gemini Multi-Object Spectrograph (GMOS) on the 8m
Gemini-North telescope through proposal GS-2014A-Q-36 (PI: Berger).
We observed GRB 140311A with the Combined Array for Research in
Millimeter Astronomy (CARMA) beginning on 2014 March 13.32 UT (1.66
days after the burst; PI: Zauderer) in continuum wide-band mode with
8GHz bandwidth at a mean frequency of 85.5GHz. Following an initial
detection, we obtained two additional epochs. We summarize our
millimeter-band observations in Table 5.
We observed the afterglow using the Karl G. Jansky Very Large Array
(VLA) starting 2.48 days after the burst through program 14A-344
(PI: Berger). We detected and tracked the flux density of the
afterglow from 1.2GHz to 37GHz over six epochs until 82.3 days after
the burst. We list the results of our VLA observations in Table 5.
Objects:
------------------------------------------------------------------
RA (ICRS) DE Designation(s) (z)
------------------------------------------------------------------
13 57 13.29 +00 38 31.7 GRB 140311A = GRB 140311A (z=4.95)
------------------------------------------------------------------
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table2.dat 23 18 Swift UVOT observations of GRB 140311A
table3.dat 77 24 Optical observations of GRB 140311A
table5.dat 50 57 GRB 140311A: Log of radio observations
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See also:
J/ApJ/833/88 : GRB 160509A VLA monitoring campain results (Laskar+, 2016)
J/ApJ/829/7 : The third Swift/BAT GRB catalog (BAT3) (Lien+, 2016)
J/ApJ/814/1 : GRB 120326A, 100418A + 100901A multi-wavelength obs.
(Laskar+, 2015)
J/ApJ/781/37 : Multi-band photometry of GRB 130427A (Perley+, 2014)
J/A+A/557/A12 : Optical light curves of γ-ray bursts (Zaninoni+, 2013)
J/MNRAS/428/729 : GRB Swift X-ray light curves analysis (Margutti+, 2013)
J/ApJ/746/156 : Radio afterglow observations of GRBs (Chandra+, 2012)
J/MNRAS/397/1177 : Swift-XRT observations of GRBs (Evans+, 2009)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 E9.3 d dt [0.1/5.6] Time since event
11- 13 A3 --- Filt Swift UVOT filter
15- 23 E9.3 mJy UL [0.001/0.2] 3σ Swift UVOT
upper limit in Filt
--------------------------------------------------------------------------------
Byte-by-byte Description of file: table3.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 E9.3 d dt [0.0001/2.1] Time since event
11- 24 A14 --- Obs Observatory
26- 33 A8 --- Tel Instrument/Telescope
35- 36 A2 --- Filt Filter (1)
38- 45 E8.2 Hz Freq [2.9e+14/4.6e+14] Frequency
47- 55 E9.3 mJy S [0.003/7.7] Flux density (2)
57- 65 E9.3 mJy e_S [0.0002/2.6] Uncertainty in S (2)
67 I1 --- Det [0/1] Detection? 1=yes
69- 77 A9 --- Ref Reference (GCN # or this work)
--------------------------------------------------------------------------------
Note (1): CR indicates clear filter calibrated to R-band.
Note (2): An uncertainty of 0.2 AB mag is assumed where not provided.
All upper limits are 3σ. The data have not been corrected for
Galactic extinction.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 F8.5 d dt [1.6/82.4] Time since event
10- 14 A5 --- Tel Facility (VLA or CARMA)
16- 26 E11.5 Hz Freq [1.4e+09/8.6e+10] Frequency
28- 37 E10.4 uJy S [0.03/0.7] Flux density at Freq
39- 48 E10.4 uJy e_S [0.01/0.2] Uncertainty in S
50 I1 --- Det [0/1] Detection? 1=yes
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 18-Mar-2019