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GRB 140901A

GCN Circular 16761

Subject

IPN Triangulation of GRB 140901A (short/hard/very intense)

Date

2014-09-02T11:36:07Z (11 years ago)

From

Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>

K. Hurley, and V. Pal'shin on behalf of the IPN team,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein, 
on behalf of the Fermi GBM 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

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on
behalf of the GRS-Odyssey GRB team, report:

A short-duration, hard spectrum, very intense GRB 140901A has been 
observed by Fermi(GBM trigger 431293300), Mars Odyssey (HEND), and 
INTEGRAL (SPI-ACS), so far, at about 70897 s UT (19:41:37).

We have triangulated it to a preliminary, 3 sigma error box whose 
coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
    15.816 (01h 03m 16s) -32.755 (-32d 45' 19")
  Corners:
    15.165 (01h 00m 40s) -32.225 (-32d 13' 30")
    14.965 (00h 59m 52s) -32.345 (-32d 20' 44")
    16.481 (01h 05m 55s) -33.279 (-33d 16' 43")
    16.682 (01h 06m 44s) -33.156 (-33d 09' 20")
  ---------------------------------------------
The error box area is 1125 sq. arcmin, and its maximum
dimension is 1.66 deg (the minimum one is 12 arcmin).
The Sun distance was 139 deg.

This box can be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB140901_T70897/IPN/

The time history and spectrum will be given in forthcoming GCN Circulars.

GCN Circular 16762

Subject

GRB 140901A: Fermi GBM detection

Date

2014-09-02T19:03:37Z (11 years ago)

From

Peter Jenke at MSFC <peter.a.jenke@nasa.gov>

P. Jenke (UAH) reports on behalf of the Fermi GBM Team:

"At 19:41:37.57 UT on September 1 2014, the Fermi Gamma-Ray Burst 
Monitor triggered and located 
GRB 140901A (trigger 431293300/140901821). The GBM on-ground 
location, using the Fermi GBM trigger data, is consistent with
the IPN Triangulation (K. Hurley et al. 2014, GCN 16761Loading...
 
 ).

The angle of the burst direction to the Fermi LAT boresight is 
97 degrees.

The GBM light curve consists of a single peak with a duration
(T90) of about 0.16 s (50-300 keV).
The time-averaged spectrum from T0+0.0 s to T0+0.19 s is
adequately fit by a Band function with Epeak = 1250 +/- 70 keV,
Alpha =-0.30 +/- 0.04 and Beta = -3.0 +/- 0.1.

The event fluence (10-1000 keV) in this time interval is
(4.8 +/- 0.1)E-06 erg/cm^2. The 64 ms peak photon flux measured
starting from T0+0.0 s in the 10-1000 keV band
is 50 +/- 2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."