GRB 160519A

P. D'Avanzo (INAF-OAB), S. D. Barthelmy (GSFC) and J. A. Kennea (PSU)
report on behalf of the Swift Team:

At 00:17:33 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 160519A (trigger=686818).  Swift did not slew due to Sun constraint. 
The BAT on-board calculated location is 
RA, Dec 71.113, +31.197, which is 
   RA(J2000)  =  04h 44m 27s
   Dec(J2000) = +31d 11' 48"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a single, possibly multiple,
peaks with a duration of about 6 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~0 sec after the trigger. 

Due to a Sun observing constraint, Swift cannot slew to the BAT
position until 11:24 UT on 2016 July 22. There will thus be no XRT or
UVOT data for this trigger before this time. 

Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.inaf.it). 
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.)

P Veres (UAH) and C Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 2016-05-19 00:17:33.55 UT on 19 May 2016, the Fermi Gamma-Ray
Burst Monitor triggered and located GRB 160519A (trigger 485309857 /
160519012), which was also detected by Swift (D'Avanzo et al., GCN
19436
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 ). The GBM on-ground location is consistent with the Swift
position.

The angle from the Fermi LAT boresight to the best location is 52 degrees.

The GBM light curve consists of multiple, weak emission episodes
with a duration (T90) of about 97 s (50-300 keV).
The time-averaged spectrum from T0-3.6 s to T0+40.4 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.97 +/- 0.25 and
the cutoff energy, parameterized as Epeak, is 61.7 +/- 7.3 keV.

The event fluence (10-1000 keV) in this time interval is
(1.4 +/- 0.1)E-6 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.2 s in the 10-1000 keV band
is 3.3 +/- 0.2 ph/s/cm^2.

A Band function fits the spectrum equally well
with Epeak = 51 +/- 11 keV, alpha = -0.67 +/- 0.51 and beta = -2.51 +/- 0.36.

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

M. Stamatikos (OSU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
P. D'Avanzo (INAF-OAB), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), D. M. Palmer (LANL),
T. Sakamoto (AGU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):

Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 160519A (trigger #686818)
(D'Avanzo, et al., GCN Circ. 19436
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 ).  The BAT ground-calculated position is
RA, Dec = 71.122, 31.246 deg which is
  RA(J2000)  =  04h 44m 29.2s
  Dec(J2000) = +31d 14' 46.1"
with an uncertainty of 2.2 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 19%.

The mask-weighted light curve shows a single-pulse structure that starts
at ~ T-1 s, peaks at ~T0, and ends at ~T+3 s. There are some weak emissions
extend till ~T+40 s. T90 (15-350 keV) is 35.57 +- 6.11 sec (estimated error
including systematics).

The time-averaged spectrum from T-0.99 to T+41.12 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.95 +- 0.25.  The fluence in the 15-150 keV band is 1.2 +- 0.2 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T-0.16 sec in the 15-150 keV band
is 2.4 +- 0.5 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/686818/BA/

K. P. Mooley, T. D. Staley, R. P. Fender (Oxford), G. E. Anderson 
(Curtin), T. Cantwell (Manchester), C. Rumsey, D. Titterington, S. H. 
Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods, P. Scott (Cambridge), 
K. Grainge, A. Scaife (Manchester)

The AMI Large Array robotically triggered on the Swift alert for GRB 
160519A (D'Avanzo et al., GCN 19436
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 ) as part of the 4pisky program, and 
subsequent follow up observations were obtained up to 10 days 
post-burst. Our observations at 15 GHz on 2016 May 19.35, May 20.50, May 
22.61, May 26.50, and May 29.49 (UT) do not reveal any variable radio 
source within the BAT error circle (Stamatikos et al., GCN 19441
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 ), with 
3sigma upper limits of 202 uJy, 72 uJy, 84 uJy, 87 uJy, and 87 uJy 
respectively.

We thank the AMI staff for scheduling these observations. The AMI-GRB 
database is a log of all GRB follow up observations with the AMI, and is 
available at http://4pisky.org/ami-grb/.