GRB 140516A

M. G. Bernardini (INAF-OAB), S. D. Barthelmy (GSFC),
S. B. Cenko (GSFC), P. D'Avanzo (INAF-OAB), J. A. Kennea (PSU),
N. P. M. Kuin (UCL-MSSL), A. Y. Lien (NASA/GSFC/ORAU),
V. Mangano (PSU), C. B. Markwardt (NASA/GSFC),
F. E. Marshall (NASA/GSFC), A. Maselli (INAF-IASFPA),
A. Melandri (INAF-OAB), D. M. Palmer (LANL),
J. L. Racusin (NASA/GSFC), B. Sbarufatti (INAF-OAB/PSU),
M. H. Siegel (PSU) and T. N. Ukwatta (MSU) report on behalf of the
Swift Team:

At 20:30:54 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 140516A (trigger=599188).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 252.988, +39.915 which is 
   RA(J2000) = 16h 51m 57s
   Dec(J2000) = +39d 54' 53"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a single-peaked
structure with a duration of about 0.1 sec.  The peak count rate
was ~3000 counts/sec (15-350 keV), at ~0.1 sec after the trigger. 

The XRT began observing the field at 20:32:14.0 UT, 79.3 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 252.9890, 39.9626 which
is equivalent to:
   RA(J2000)  = 16h 51m 57.35s
   Dec(J2000) = +39d 57' 45.4"
with an uncertainty of 2.7 arcseconds (radius, 90% containment). This
location is 171 arcseconds from the BAT onboard position, within the
BAT error circle. This position may be improved as more data are
received; the latest position is available at
http://www.swift.ac.uk/sper.  We cannot determine whether the source is
fading at the present time. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.52
x 10^20 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White filter
starting 83 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers none of
the XRT error circle. The 8'x8' region for the list of sources generated
on-board covers 100% of the XRT error circle. The list of sources is typically
complete to about 18 mag. No correction has been made for the expected
extinction corresponding to E(B-V) of 0.02. 

Burst Advocate for this burst is M. G. Bernardini (grazia.bernardini 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 D'Avanzo, A. Melandri, M. G. Bernardini (INAF-OAB), M. Cecconi, G. Mainella (INAF/TNG) 
report on behalf of a larger collaboration:


We observed the field of the short GRB 140516A (Bernardini et al. GCN 16285
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 )
using the DOLORES camera on the 3.6m TNG telescope sited in Canary Islands. 
We obtained four images with the r SDSS filter, each one lasting 180 s, at a mean
time of 1.55 hours after the burst.

In the co-added image we do not detect any optical afterglow inside the XRT 
error circle reported by Bernardini et al. (GCN 16285
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 ). The 3sigma limiting
magnitude is r = 23.0 (AB).

V. Nevskiy (ISON), V. Linkov (ISON), A. Volnova (IKI),  I. Molotov (KIAM), 
A. Pozanenko (IKI),  report on  behalf of larger collaboration:

We observed the field of  GRB 140516A (Bernardini et al., GCN 16285
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 ) with 
ORI-40 (0.4-m f/3)  telescope of ISON-Kislovodsk observatory. Observations 
started on  May 16 (UT) 20:39:04 and continued up to (UT) 21:11:60.   We 
obtained  several unfiltered images  of 30 s and 100 s exposures. In a 
preliminary analysis we do not detect evident source within XRT error circle 
(Bernardini et al., GCN 16285
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 ) .  The upper limit of a combined image is 
20.5m and based on USNO-B1.0 (R2) nearby stars.

E. Gorbovskoy, V. Lipunov, V.Kornilov, D.Kuvshinov, A.Belinski, N.Tyurina, 
N.Shatskiy, P.Balanutsa, D.Zimnukhov, A.Kuznetsov, V.V.Chazov, 
D.Denisenko, A.Sankovich
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University

A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory

V.Yurkov, Yu.Sergienko, D.Varda, E.Sinyakov
Blagoveschensk Educational State University, Blagoveschensk

K.Ivanov, S.Yazev, N.M.Budnev, O.Gres, O.Chuvalaev, V.A.Poleshchuk
Irkutsk State University

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 (MASTER-Net: http://observ.pereplet.ru) 
located in Kislovodsk was pointed to the  GRB140516A 22 sec after notice 
time 44 sec after trigger time at 2014-05-16 20:31:39 UT in two 
polarizations. On our first (10s exposure) set we haven`t found optical 
transient  within SWIFT error-box (Bernardini et. al GCN 16285
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 ). The 
5-sigma upper limit has been about 17.0 mag.
As we have a set of observations after that with exposures from 10 to 180 
seconds during several hours.  In table 1 some limits are provided.

Table 1
-------
T_start 	   Exptime   T-T_mead  T-T_start  T-T_stop  Filter  mlimit  Coadd
2014-05-16 20:31:39     10     49 sec     44 sec     54 sec   P|     17.0    1
2014-05-16 20:31:39     10     49 sec     44 sec     54 sec   P-     16.9    1
2014-05-16 20:31:39    780    466 sec     44 sec    889 sec   P|     19.6    13*
2014-05-16 20:31:39    780    466 sec     44 sec    889 sec   P|     19.3    13*
2014-05-16 20:45:54   3600   2914 sec    899 sec   4930 sec   P|     20.6    20
2014-05-16 20:45:54   3600   2914 sec    899 sec   4930 sec   P-     20.4    20
2014-05-16 20:45:54   7200   2914 sec    899 sec   4930 sec P| + P-  21.0    40**
---------------------------------------------------------------------------------
*  This is a set images with diffrent exposure times from 10 to 180 seconds.
** We has images synchronously in 2 channels. Therefore we can increase 
twice exptime in case of constant t_start and t_stop.

P- and P| is a polarization filter which are oriented at an angle 0 and 90 
degrees to RA axis respectivel. T is a  GRB trigger time.


The message may be cited.

J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 461 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 140516A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 252.98931, +39.96284 which is equivalent
to:

RA (J2000): 16h 51m 57.43s
Dec (J2000): +39d 57' 46.2"

with an uncertainty of 2.4 arcsec (radius, 90% confidence).

This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).

This circular was automatically generated, and is an official product of the
Swift-XRT team.

J. Gorosabel (IAA-CSIC, UPV-EHU), D. Xu (DARK/NBI), A. de Ugarte Postigo
(IAA-CSIC, DARK/NBI), J.P.U. Fynbo (DARK/NBI), P. Jakobsson (U. Iceland),
D. Malesani (DARK/NBI), N.R. Tanvir (U. Leicester), D. Watson (DARK/NBI),
E. Gafton (OKC, Stockholm Univ.) and T. Libbrecht (Stockholm Univ.), report
on behalf of a larger collaboration:

We imaged the field of GRB 140516A (Bernardini et al. GCNC 16285) with the
2.5m Nordic Optical telescope equipped with ALFOSC. The observations were
carried out in the R-band on May 16.89163-16.97005 UT (0.88-2.77 hours post
burst) with a total exposure time of 13x300s. We did not detect any objects
brighter than R=24.5 (3 sigma Vega limit calibrated against USNO B1.0)
consistent with the enhanced XRT position (Osborne et al. GCNC 16289).

[GCN OPS NOTE(17may14): Changed the Subject-line from 150416A to 140516A.]

B.P. Gompertz (U. Leicester), M. de Pasquale (INAF-IASFPA), A. Maselli 
(INAF-IASFPA), A. Melandri (INAF-OAB), M.C. Stroh (PSU), D.N. Burrows
(PSU), J.A. Kennea (PSU), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester) and M.G. Bernardini report on behalf of the Swift-XRT team:

We have analysed 11 ks of XRT data for GRB 140516A (Bernardini	et al.
GCN Circ. 16285
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 ),  from 64 s to 25.6 ks after the  BAT trigger. The
data comprise 8 s in Windowed Timing (WT) mode (taken while Swift was
slewing), with the remainder in Photon Counting (PC) mode. The enhanced
XRT position for this burst was given by Osborne et al. (GCN Circ.
16289
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 ).

The light curve can be modelled with  a power-law decay with a decay
index of alpha=0.38 (+0.14, -0.12).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.2 (+0.7, -0.4). The
best-fitting absorption column is  2 (+14, -0) x 10^20 cm^-2,
consistent with the Galactic value of 1.5 x 10^20 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum  is 2.9 x 10^-11 (3.1 x
10^-11) erg cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     2 (+14, -0) x 10^20 cm^-2
Galactic foreground: 1.5 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index:	     2.2 (+0.7, -0.4)

If the light curve continues to decay with a power-law decay index of
0.38, the count rate at T+24 hours will be 1.6 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 4.7 x
10^-14 (5.0 x 10^-14) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00599188.

This circular is an official product of the Swift-XRT team.

M. Stamatikos (OSU), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
M. G. Bernardini (INAF-OAB), J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC),
H. A. Krimm (GSFC/USRA), A. Y. Lien (NASA/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
 
Using the data set from T-240 to T+962 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 140516A (trigger #599188)
(Bernardini, et al., GCN Circ. 16285
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 ).  The BAT ground-calculated position is
RA, Dec = 252.972, 39.958 deg, which is 
   RA(J2000)  =  16h 51m 53.2s 
   Dec(J2000) = +39d 57' 28.5" 
with an uncertainty of 2.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 75%.
 
The mask-weighted light curve shows a single spike starting at ~T+0.0,
peaking at ~T+0.05, and ending at ~T+0.3 sec.  T90 (15-350 keV)
is 0.19 +- 0.09 sec (estimated error including systematics).
 
The time-averaged spectrum from T-0.01 to T+0.18 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.87 +- 0.33.  The fluence in the 15-150 keV band is 2.3 +- 0.6 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T-0.38 sec in the 15-150 keV band
is 0.5 +- 0.1 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/599188/BA/

N. P. M. Kuin (UCL-MSSL) and Bernardini (INAF-OAB) report on
behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 140516A
84 s after the BAT trigger (Bernardini et al., GCN Circ. 16285
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 ).
No optical afterglow consistent with the XRT enhanced position
(Osborne et al. GCN Circ. 16289
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 ) is detected in the initial UVOT
exposures. The Enhanced position overlaps with the PSF wings of
a star, and the light curve is consistent with a constant source.
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:

Filter         T_start(s)   T_stop(s)      Exp(s)         Mag

white_FC            84          234          147         >20.5
u_FC               298          547          246         >21.2
white               84        12686         1178         >20.6
v                  627         7762          607         >19.5
b                  553        12381         1294         >20.9
u                  298         8313          770         >21.0
w1                 676         8172          607         >21.6
m2                 651         7967          529         >21.0
w2                 602         7558          607         >21.1

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the burst
(Schlegel et al. 1998).

W. Fong and E. Berger (Harvard) report:

"We observed the location of the short-duration GRB 140516A (Bernardini et
al., GCN 16285
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 ) with the Gemini Multi-Object Spectrograph (GMOS) mounted on
the Gemini-North 8-meter telescope at a mid-time of 2014 May 17.373 UT
(12.38 hr post-burst). We obtained i-band observations for a total of
1800-sec in 0.5" seeing. We do not detect any optical source within the XRT
position (Osborne et al., GCN 16289
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 ). Calibrated to SDSS, we therefore
place a 3-sigma limit of i>26.1 AB mag on the optical afterglow of GRB
140516A at 12.38 hr after the burst.

We thank Gemini observer Lucas Fuhrman for assistance with these
observations."

W. Fong, B. A. Zauderer and E. Berger (Harvard) report:

"We observed the field of the short-duration GRB 140516A (Bernardini et
al., GCN 16285
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 ) with the Karl G. Jansky Very Large Array (VLA) beginning on
2014 May 17.48 UT (14.94 hr post-burst) at a mean frequency of 6 GHz. In 1
hour of observations, we do not detect any radio source in or around the
enhanced XRT position (Osborne et al., GCN 16289
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 ). We therefore place a
3-sigma limit of 24 microJy on the radio afterglow of GRB 140516A at 14.94
hr after the burst.

We thank the VLA staff for quickly executing these observations."

Y. Minowa, T.-S. Pyo, J.-H. Kim (Subaru, NAOJ)
and N. Kawai (Tokyo Tech) report on behalf of the Subaru GRB team:

We observed the field of the short GRB 140516A (Bernardini et al.,
GCN 16285
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 ) using IRCS+AO188 on the 8.2 m Subaru telescope, 
starting from 06:56 on May 17, 2014 UTC (about 10.4 hrs from the 
burst). We obtained the Kp-band images in 52 mas/pixel mode 
without AO correction for a total exposure time of 5880 sec under 
0".7 seeing condition. We do not detect any source within the 
error circle reported by Osborne et al. (GCN 16289
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 ). We obtained 
the 3-sigma limit on the near-infrared afterglow of GRB 140516A 
of Kp>22.2 mag (Vega) at 10.4-12.7 hrs after the burst.

Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico
Ramirez-Ruiz (UCSC), Jos�� A. de Diego (UNAM), Leonid Georgiev (UNAM), Jes��s
Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Neil Gehrels (GSFC), and
Harvey Moseley (GSFC) report:

We observed the field of the short-duration GRB 140516A (Bernardini, et
al., GCN 16285
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 ) with the Reionization and Transients Infrared Camera
(RATIR; www.ratir.org) on the 1.5m Harold Johnson Telescope at the
Observatorio Astron��mico Nacional on Sierra San Pedro M��rtir from 2014/05
17.33 to 2014/05 17.46 UTC (11.41 to 14.56 hours after the BAT trigger),
obtaining a total of 2.13 hours exposure in the r and i bands and 0.89
hours exposure in the Z, Y, J, and H bands.

For a source within the Swift-XRT error circle (Osborne, et al., GCN
16289
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 ), in comparison with the SDSS DR9 and 2MASS, we obtain the following
upper limits (3-sigma):

  r     > 23.57
  i     > 23.39
  Z     > 21.70
  Y     > 21.52
  J     > 22.00
  H     > 21.48

These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.

We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.

M. G. Bernardini, P. D'Avanzo, A. Melandri, S. Campana (INAF-OAB), P. A. Evans, K. L. Page (U. Leicester), 
E. Troja (NASA/GSFC/UMCP) report on behalf of the Swift-XRT team:


We have analysed 24.4 ks of XRT data for GRB 140516A (Bernardini et al. GCN Circ. 16285
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 ),  
from 92 s to 397.8 ks after the  BAT trigger, in Photon Counting (PC) mode. 

The X-ray counterpart reported by Bernardini et al. (GCN Circ. 16285
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 ) and Gompertz 
et al. (GCN Circ. 16291
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 ) apparently disappeared in the data collected from t-t0=92.8 ks onwards. 
However, in the same dataset we find evidence for the presence of an unrelated source at 
the position RA, Dec = 252.99269, +39.95659 which is equivalent to:

RA (J2000): 16h 51m 58.25s
Dec (J2000): +39d 57' 23.7"

with an uncertainty of 4.0 arcsec (radius, 90% confidence).

This position is 24" away from the enhanced position for this burst reported by
Osborne et al. (GCN Circ. 16289
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 ) while it is consistent with the source
165158.53+395728.9 reported in the Krawczyk et al. (2013; ApJS, 206, 4) QSO
catalogue. 
We therefore caution that this field source is likely contaminating the automated late-time 
X-ray light curve of GRB 140516A, given the spatial proximity to its transient 
X-ray counterpart.

[GCN OPS NOTE(22may14): Per author's request, the word "automated" was added 
to the last sentence.]