GRB 140721A

H.-F. Yu (MPE) reports on behalf of the Fermi GBM Team:

"At 08:03:22.32 UT on 21 July 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 140721A (trigger 427622605 / 140721336).

The on-ground calculated location, using the GBM trigger data, is 
RA = 175.7, Dec = -41.2 (J2000 degrees, equivalent to 11h 42m 48s, 
-41d 12'), with an uncertainty of 1.0 degrees (radius, 1-sigma
containment, statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).

The angle from the Fermi LAT boresight is 118 degrees.

The GBM light curve shows a multi-pulse feature with a duration
(T90) of about 128 s (50-300 keV). The time-averaged spectrum from 
T0-6.400 s to T0+84.737 s is well fit by a Band function with 
Epeak = 129.0 +/- 10.2 keV, alpha = -1.05 +/- 0.05, 
and beta = -1.98 +/- 0.03.

The event fluence (10-1000 keV) in this time interval is
(4.95 +/- 0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+18.752 s in the 10-1000 keV band
is 14.0 +/- 0.5 ph/s/cm^2.

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

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,

G. Di Cocco, F. Fuschino, M. Galli, C. Labanti, and M. Marisaldi, on
behalf of the AGILE MCAL 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

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

The long-duration GRB 140721A (Yu, GCN Circ. 16617
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 ) has been observed by 
Konus-Wind, Fermi(GBM trigger 427622605), MESSENGER (GRNS), AGILE (MCAL) 
and INTEGRAL (SPI-ACS), so far, at about 29002 s UT (08:03:22).

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
  ---------------------------------------------
   RA(2000), deg                 Dec(2000), deg
  ---------------------------------------------
  Center:
   177.645 (11h 50m 35s) -37.735 (-37d 44' 06")
  Corners:
   181.410 (12h 05m 38s) -30.317 (-30d 19' 01")
   172.431 (11h 29m 43s) -44.878 (-44d 52' 41")
   174.251 (11h 37m 00s) -43.513 (-43d 30' 47")
   183.534 (12h 14m 08s) -27.322 (-27d 19' 20")
  ---------------------------------------------
The error box area is 8.7 sq. deg, and its maximum
dimension is 19.7 deg (the minimum one is 0.52 deg).

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB140721_T29009/IPN/

Details of the Konus-Wind observation will be given in a forthcoming GCN
Circular.

S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik,
M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lyssenko, and T. Cline
on behalf of the Konus-Wind team, report:

The long-duration GRB 140721A (Fermi-GBM detection: Yu, GCN 16617
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 ;
IPN triangulation: Hurley et al., GCN 16620
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 )
triggered Konus-Wind at T0=29009.138 s UT (08:03:29.138).

The light curve shows a multi-peaked structure which
started ~60 s before the trigger.
A total duration of the burst is ~160 s.
The emission is seen up to 5 MeV.

As observed by Konus-Wind, the burst had a fluence
of 4.7(-0.4,+0.4)x10^-5 erg/cm2, and a 64-ms peak flux,
measured from T0+10.496 s, of 5.0(-0.5,+0.5)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The time-averaged spectrum (measured from T0 to T0+98.560 s)
is best fit in the 20 keV - 10 MeV range
by the cutoff power law with the following model parameters:
the photon index alpha = -1.31(-0.11,+0.12),
and the peak energy Ep = 153(-15,+19) keV,
chi2 = 65/85 dof.
Fitting this spectrum with the Band model yields the same
values of alpha and Ep with an upper limit on beta of -2.5

The spectrum near the peak count rate (measured from T0 to T0+16.640 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 = -0.94 (-0.20,+0.24),
the high energy photon index beta = -2.15 (-0.24,+0.13),
the peak energy Ep = 166 (-29,+44) keV,
chi2 = 60/87 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB140721_T29009/

All the quoted errors are at the 90% sigma confidence level.
All the quoted values are preliminary.