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GRB 180614A

GCN Circular 22780

Subject
GRB 180614A: Swift detection of a burst
Date
2018-06-14T19:28:07Z (7 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
J.D. Gropp (PSU), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
J. A. Kennea (PSU), A. Y. Lien (GSFC/UMBC),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), M. H. Siegel (PSU),
A. Tohuvavohu (PSU) and T. N. Ukwatta (LANL) report on behalf of the
Neil Gehrels Swift Observatory Team:

At 19:16:13 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 180614A (trigger=841548).  Swift slewed immediately to the burst. 
The BAT on-board calculated location is 
RA, Dec 3.157, +46.943, which is 
   RA(J2000)  =  00h 12m 38s
   Dec(J2000) = +46d 56' 34"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve shows a couple peaks
with a duration of about 25 sec.  The peak count rate
was ~1500 counts/sec (15-350 keV), at ~2 sec after the trigger. 

The XRT began observing the field at 19:17:19.1 UT, 65.6 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source located at RA, Dec 3.07620, 46.95342 which is equivalent
to:
   RA(J2000)  = 00h 12m 18.29s
   Dec(J2000) = +46d 57' 12.3"
with an uncertainty of 4.0 arcseconds (radius, 90% containment). This
location is 202 arcseconds from the BAT onboard position. 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. This position is more than
2-sigma away from the BAT position, and so possibly unrelated to the
trigger. 

A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.14
x 10^21 cm^-2 (Willingale et al. 2013). 

UVOT took a finding chart exposure of 150 seconds with the White
filter  starting 68 seconds after the BAT trigger. No credible
afterglow candidate has  been found in the initial data products. The
2.7'x2.7' image covers none of the XRT  error circle. Data from the list of
sources generated  on-board are not available at this time. 

Burst Advocate for this burst is J.D. Gropp (jdg44 AT psu.edu). 
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.)

GCN Circular 22781

Subject
GRB 180614A: Enhanced Swift-XRT position
Date
2018-06-15T03:10:39Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester) 
report on behalf of the Swift-XRT team.

Using 1822 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 180614A, 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 = 3.07846, +46.95299 which is equivalent
to:

RA (J2000): 00h 12m 18.83s
Dec (J2000): +46d 57' 10.8"

with an uncertainty of 1.8 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.

GCN Circular 22782

Subject
GRB 180614A: Swift-XRT refined Analysis
Date
2018-06-15T04:15:27Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A.P. Beardmore (U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia
(ASDC), A. D'Ai (INAF-IASFPA), B. Sbarufatti (INAF-OAB/PSU), D.N.
Burrows (PSU), A. Tohuvavohu (PSU), P.A. Evans (U. Leicester), S.L.
Gibson (U. Leicester) and J.D. Gropp report on behalf of the Swift-XRT
team:

We have analysed 6.9 ks of XRT data for GRB 180614A (Gropp et al. GCN
Circ. 22780), from 77 s to 24.9 ks after the  BAT trigger. The data are
entirely in Photon Counting (PC) mode. The enhanced XRT position for
this burst was given by Evans et al. (GCN Circ. 22781).

The light curve can be modelled with a power-law decay with a decay
index of alpha=0.70 (+/-0.06).

A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.8 (+/-0.4). The
best-fitting absorption column is  1.7 (+0.5, -0.4) x 10^22 cm^-2, in
excess of the Galactic value of 1.1 x 10^21 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum  is 4.0 x 10^-11 (2.0 x 10^-10) erg
cm^-2 count^-1. 

A summary of the PC-mode spectrum is thus:
Total column:	     1.7 (+0.5, -0.4) x 10^22 cm^-2
Galactic foreground: 1.1 x 10^21 cm^-2
Excess significance: 6.8 sigma
Photon index:	     2.8 (+/-0.4)

If the light curve continues to decay with a power-law decay index of
0.70, the count rate at T+24 hours will be 4.7 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.9 x
10^-13 (9.2 x 10^-13) erg cm^-2 s^-1.

The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00841548.

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

GCN Circular 22783

Subject
GRB 180614A: MASTER observation
Date
2018-06-15T11:28:04Z (7 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, A.Kuznetsov,
I. Gorbunov, D. Vlasenko, D.Zimnukhov, D.Kuvshinov, P.Balanutsa, V.Vladimirov
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University

R. Podesta, F. Podesta, C. Lopez, C.Francile
Observatorio Astronomico Felix Aguilar (OAFA)

H.Levato, C. Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)

R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
The Instituto de Astrofisica de Canarias

D. Buckley
South African Astronomical Observatory

O. Gres, N.M.Budnev , Yu.Ishmuhametova
Irkutsk State University

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

A. Gabovich, V. Yurkov, Yu. Sergienko
Blagoveschensk Educational State University, Blagoveschensk

MASTER-Kislovodsk  robotic telescope (MASTER-Net: http://observ.pereplet.ru  Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) ,
located in Kislovodsk Solar Station of Pulkovo observatory,
was pointed to the Swift GRB180614A (Gropp et al. GCN #22780)
11 sec after notice time and 26 sec after trigger time at 2018-06-14 19:16:40 UT.

On our images we  didn't find optical transient  up to 20 mag, within SWIFT error-box
RA,Dec=00h 12m 18.83s +46d 57' 10.8"  ( Evans et al. GCN22781, Beardmore et al. GCN22782).

We have a number of  images  with the following unfiltered upper limits:

Time_start,UT              Exp,s  m_lim

2018-06-14 19:16:40	10	16.6
2018-06-14 19:17:00	10	16.5
2018-06-14 19:17:20	10	16.7
2018-06-14 19:17:41	20	17.1
2018-06-14 19:18:11	20	17.2
2018-06-14 19:18:41	30	17.3
2018-06-14 19:19:21	40	17.6
2018-06-14 19:20:11	50	17.8
2018-06-14 19:21:12	60	18.0
2018-06-14 19:22:22	70	18.0
2018-06-14 19:25:23	110	18.4
2018-06-14 19:27:23	130	18.4
2018-06-14 19:33:27	180	18.3
2018-06-14 19:33:27    3600     20.0 [20 images x 180 seconds]
2018-06-14 19:36:52	180	18.3
2018-06-14 19:40:16	180	18.3
2018-06-14 19:43:41	180	18.3
2018-06-14 19:47:05	180	18.4
2018-06-14 19:50:29	180	18.6
2018-06-14 19:53:54	180	18.5
2018-06-14 19:57:18	180	18.6
2018-06-14 20:00:43	180	18.6
2018-06-14 20:04:07	180	18.6
2018-06-14 20:07:31	180	18.6
2018-06-14 20:10:55	180	18.6
2018-06-14 20:14:20	180	18.6
2018-06-14 20:17:45	180	18.6
2018-06-14 20:21:09	180	18.8
2018-06-14 20:24:34	180	18.6
2018-06-14 20:27:59	180	18.6
2018-06-14 20:31:23	180	18.9
2018-06-14 20:34:48	180	18.8
2018-06-14 20:38:12	180	18.8
====================================================================
The observations started on zenit distance = 78 degrees, galaxy latitude b = -15 degree.
The moon ( 2 % bright part) below the horizon (The altitude of the Moon is  -15 degree ).
The sun  altitude  is -18.8 degree.
The object could be observed up to sunrise at 2018-06-15 01:26:34

GCN Circular 22784

Subject
GRB 180614A: NOT optical upper limits
Date
2018-06-15T12:42:31Z (7 years ago)
From
Kasper Elm Heintz at Univ. of Iceland and DAWN/NBI <keh14@hi.is>
Kasper E. Heintz (Univ. of Iceland and DAWN/NBI), Johan P. U. Fynbo (DAWN/NBI), Daniele B. Malesani (DAWN/NBI and DARK/NBI), Jyri J. Lehtinen (MPS), Teemu Willamo (Univ. of Helsinki), and Paco Galindo (NOT), report on behalf of a larger collaboration:

We observed the field around GRB 180614A (Gropp et al., GCN 22780) with the 2.5-m Nordic Optical Telescope (NOT) equipped with StanCam.

Observations of 3x100 s were carried out in the R filter and started at 04:12:59 UT on June 15, 8.93 hr after trigger. We do not detect the optical counterpart within the enhanced Swift-XRT error circle and calibrated against local photometry from the USNO-B1 catalog we measure an upper limit (at 3-sigma) of m(R) > 22.9 AB mag.

This upper limit is not corrected for the Galactic extinction of A_V = 0.36 mag (Schlafly & Finkbeiner, 2011, ApJ, 737, 103) in the direction of the GRB.

GCN Circular 22786

Subject
GRB 180614A: Swift-BAT refined analysis
Date
2018-06-15T16:03:33Z (7 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), J. D. Gropp (PSU),
H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), T. Sakamoto (AGU),
M. Stamatikos (OSU), 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 180614A (trigger #841548)
(Gropp et al., GCN Circ. 22780).  The BAT ground-calculated position is
RA, Dec = 3.073, 46.969 deg which is
  RA(J2000)  =  00h 12m 17.6s
  Dec(J2000) = +46d 58' 07.7"
with an uncertainty of 1.9 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.

The mask-weighted light curve shows a multi-peaked structure that starts
at ~T-4 s and ends at ~T+3 s. The main peak occurs at ~T+2 s.
T90 (15-350 keV) is 7.04 +- 0.92 sec (estimated error including systematics).

The time-averaged spectrum from T-4.35 to T+3.45 sec is best fit by a simple
power-law model.  The power law index of the time-averaged spectrum is
1.53 +- 0.26.  The fluence in the 15-150 keV band is 2.1 +- 0.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+1.56 sec in the 15-150 keV band
is 0.7 +- 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/841548/BA/

GCN Circular 22787

Subject
GRB 180614A: Swift/UVOT Upper Limits
Date
2018-06-15T17:20:41Z (7 years ago)
From
Jeffrey Gropp at PSU <jdg44@psu.edu>
J. D. Gropp (PSU) reports on behalf of the Swift/UVOT team:

The Swift/UVOT began settled observations of the field of GRB 180614A
65s after the BAT trigger (Gropp et al., GCN Circ. 22780).
No optical afterglow consistent with the enhanced XRT position
(Gropp et al. GCN Circ. 22780)
is detected in the initial UVOT exposures.
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

b              556     1872    136    >19.63
uvm2       654     1797    136    >18.91
u              300     1847    362    >20.06
v              630     1773    136    >18.75
uvw1        679     1823    136    >19.03
uvw2        605     1922    155    >19.20
white          87     1897    430    >21.15
white_FC    87      237    147    >20.75

The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.14 in the direction of the burst
(Schlegel et al. 1998).

GCN Circular 22788

Subject
GRB 180614A: 1.5m OSN I-band observation
Date
2018-06-15T21:46:08Z (7 years ago)
From
Youdong HU at IAA-CSIC, UGR <youdong@iaa.es>
Y.-D. Hu, F. Aceituno and A.J. Castro-Tirado (IAA-CSIC Granada), on 
behalf of a larger collaboration, report:

Following the detection of GRB 180614A by Swift (Gropp et al. GCNC 
22780), optical images in the I-band were obtained at the 1.5m OSN 
telescope in Granada (Spain) starting at 01:57 (Jun 15), i.e. 6.67 h 
postburst. No optical afterglow is detected in the co-added image (9 x 
600s, mid time 02:43 UT, 7.4 h after the trigger) within the enhanced 
Swift/XRT error box (Beardmore et al. GCNC 22782) down to I=21.0.

GCN Circular 22789

Subject
GRB 180614A: AbAO optical observations
Date
2018-06-16T15:19:10Z (7 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI),  A. Pozanenko (IKI),   R. Inasaridze (AbAO),  V. 
Ayvazian  (AbAO),  O. Kvaratskhelia (AbAO), G. Kapanadze (AbAO),  A. 
Volnova  (IKI), I. Molotov (KIAM), report on behalf of larger GRB 
follow-up collaboration:

We observed the field of GRB 180614A  (Gropp et al., GCN 22780) with 
AS-32 (0.7m) telescope of Abastumani Observatory starting on June 14 
(UT) 21:33:14.   We do not detect any object within enhanced XRT 
position (Evans et al., GCN 22781). Preliminary photometry of the field 
is following.

Date        UT start   t-T0      Filter Exp.   OT    Err. UL
                      (mid, days)        (s)

2018-06-14  21:33:14   0.12582   CR     51*60  n/d   n/d  21.5

The photometry is based on nearby USNO-B1.0 stars (R2 magnitude)
USNO-B.1_id R2
1369-0005473 17.71
1369-0005482 16.67
1369-0005487 16.97
1369-0005592 16.51

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