Gamma-ray Burst 140320D

(All information courtesy of the instrument teams.)

Previous IAU Circulars

none

Results of Observations

GCN Circular #16023
K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,
S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin, and T. Cline, on behalf of the Konus-Wind team,
A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and
S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer, on behalf of the Swift-BAT team, report:
The long-duration very intense GRB 140320D has been observed by Konus-Wind, INTEGRAL (SPI-ACS), Swift (BAT), and MESSENGER (GRNS), so far, at about 73297 s UT (20:21:37). The burst was outside the coded field of view of the BAT.
We have triangulated it to a preliminary, 3 sigma error box whose coordinates are:
```
   ---------------------------------------------
     RA(2000), deg                 Dec(2000), deg
    ---------------------------------------------
    Center:
      87.893 (05h 51m 34s) +85.429 (+85d 25' 46")
    Corners:
      98.997 (06h 35m 59s) +86.721 (+86d 43' 15")
      98.219 (06h 32m 53s) +87.023 (+87d 01' 23")
      81.849 (05h 27m 24s) +84.026 (+84d 01' 35")
      83.033 (05h 32m 08s) +83.741 (+83d 44' 28")
    ---------------------------------------------
```
The error box area is 0.635 sq. deg, and its maximum dimension is 3.474 deg (the minimum one is 0.196 deg).
This box may be improved.
A triangulation map is posted at http://www.ioffe.ru/LEA/GRBs/GRB140320_T73298/IPN/
The time history and spectrum will be given in a forthcoming GCN Circular.
GCN Circular #16025
S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, A. Tsvetkova, and T. Cline on behalf of the Konus-Wind team, report:
A very intense, long-duration, hard-spectrum GRB 140320D (IPN triangulation: K. Hurley et al., GCN 16023) triggered Konus-Wind at T0=73298.804 s UT (20:21:38.804).
The burst light curve shows a bright, double-peaked pulse with a total duration of ~50 s. The emission is seen up to ~10 MeV.
As observed by Konus-Wind, the burst had a fluence of (2.1 +/- 0.1)x10^-4 erg/cm2, and a 64-ms peak flux, measured from T0+15.456 s, of (6.7 +/- 0.7)x10^-5 erg/cm2/s (both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum (measured from T0 to T0+45.568 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.83 (-0.03,+0.03), the high energy photon index beta = -2.75 (-0.32,+0.20), the peak energy Ep = 575 (-30,+32) keV, chi2 = 100/87 dof.
The spectrum near the maximum count rate (measured from T0+15.360 to T0+15.872 s) is best fit in the 20 keV - 10 MeV range by the GRB (Band) function with the following model parameters: the low-energy photon index alpha = -0.30 (-0.11,+0.13), the high energy photon index beta = -2.59 (-0.62,+0.30), the peak energy Ep = 655 (-89,+102) keV, chi2 = 82/56 dof.
The Konus-Wind light curve of this GRB is available at http://www.ioffe.ru/LEA/GRBs/GRB140320_T73298/
All the quoted errors are at the 90% confidence level. All the quoted values are preliminary.
GCN Circular #16040
T. Yasuda, M. Tashiro, Y. Terada, Y. Ishida, H. Ueno, S. Sugimoto S. Koyama, S. Takeda, T. Nagayoshi (Saitama U.), M. Yamauchi, N. Ohmori, M. Akiyama, R. Kinoshita (Univ. of Miyazaki), M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa (Hiroshima U.), K. Yamaoka (Nagoya U.), S. Sugita (Ehime U.), W. Iwakiri(RIKEN), Y. Hanabata (ICRR), Y. E. Nakagawa, M. Kokubun, T. Takahashi (ISAS/JAXA), Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo) on behalf of the Suzaku WAM team, report:
The bright, long, and IPN localized GRB 140320D (Hurley et al., GCN 16023; Golenetskii et al., GCN 16025) triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range of 50 keV - 5 MeV at 20:21:38.309 UT (=T0).
The observed light curve shows a multi-peaked structure lasting from T0-5 s to T0+50 s with a duration (T90) of about 22 seconds. The fluence in 100 - 1000 keV was 1.14 (+0.03, -0.04) x10^-4 erg/cm^2. The 1-s peak flux measured from T0+17 s was 35.4 (+0.8, -0.9) photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0-10.5 s to T0+49.5 s is well fitted in 200 keV to 5 MeV by a power-law with exponential cutoff model:
```
dN/dE ~  E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha       0.99 (+0.12, -0.13), and
Epeak      746 (+33, -31) keV (chi^2/d.o.f. = 72.1/48).
```
Fitting by a GRB Band model yields the following parameters: the low-energy photon index alpha: -0.97 (+0.14, -0.13), the high-energy photon index beta: <-3.62, and the peak energy Epeak: 742 (+34, -22) keV (chi^2/d.o.f = 71.4/47).
Due to the brightness of this burst, a 3% systematic error was added for low energy channels. All the quoted errors are at statistical 90% confidence level.
The light curves for this burst will be available at: http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
GCN Circular #16043
K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk Irkutsk State University
E. Gorbovskoy, V. Lipunov, M. Pruzhinskaya, D.Denisenko, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, V.V.Chazov, D.Kuvshinov Lomonosov Moscow State University, Sternberg Astronomical Institute
V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov Blagoveschensk Educational State University, Blagoveschensk
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik Kislovodsk Solar Station of the Pulkovo Observatory
V.Krushinski, I.Zalozhnih, A. Popov Ural Federal University, Kourovka
Hugo Levato and Carlos Saffe Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
Claudio Mallamaci, Carlos Lopez and Federico Podest Observatorio Astronomico Felix Aguilar (OAFA)
MASTER II robotic telescope located in Tunka (MASTER-Net: http://observ.pereplet.ru) have done a survey of the large area around IPN error box (Hurley et. al. GCN16023). The survey was started 2014-03-21 13:15:06 i.e. 16h 53m after the burst and proceeded during 5 hours. The 5 sigma unfiltered upper limit was ~17.5 m on single 180 image and ~18.8 m on coadd of 5 images with total exposure 900 s.
We haven`t found credible optical afterglow candidate within IPN error box.
The covarege map is available at http://master.sai.msu.ru/static/GRB/GRB140320D_map.png
The message may be cited.

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Jochen Greiner, last update: 30-Mar-2014 [Disclaimer]