GRB 180705A
GCN Circular 22941
Subject
GRB 180705A: OSN observations
Date
2018-07-11T19:25:41Z (7 years ago)
From
Alexander Kann at IAA-CSIC <kann@iaa.es>
D. A. Kann, L. Izzo (both HETH/IAA-CSIC), and A. Sota (IAA/CSIC) report
on behalf of HETH:
We observed the field of GRB 180705A (Stamatikos et al., GCN #22902)
with the 1.5-m OSN telescope in Granada, Spain.
We obtained 20 x 300 s images in the Ic band centered at 0.262416 days
(6.3 hrs) after the GRB.
At the XRT position of the GRB (Goad et al., GCN #22906), there is a
possible faint source, formally detected at Ic (Vega) = 23.6 +/- 0.2
mag. We note, however, that the background of the image is structured
because of the proximity of the bright star HD 123921 (V ~ 9 mag),
therefore the detection may be spurious. The formal 3 sigma upper limit
is Ic > 24 mag, also possibly overestimated.
Even if the source we detect is not real, any afterglow of this GRB is
clearly very faint, in agreement with other non-detection reports
(Lipunov et al., GCN #22904, Watson et al., GCN #22911, Breeveld et al.,
GCN #22912, Mazaeva et al., GCN #22913, Bikmaev et al., GCN #22929).
The field was calibrated against SDSS secondary standard stars using the
transformation of Lupton (2005).
GCN Circular 22929
Subject
GRB 180705A: RTT150 optical upper limit
Date
2018-07-08T16:42:54Z (7 years ago)
From
Rodion Burenin at IKI, Moscow <rodion@hea.iki.rssi.ru>
I. Bikmaev, E. Irtuganov, N. Sakhibullin (KFU/AST),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
I. Khamitov, S. Ozdemir (TUG), E. Gogus (Sabanci Uni.)
report:
We observed the field of GRB 180705A (Stamatikos et al., GCN 22902)
with the Russian-Turkish 1.5-m optical telescope (RTT150, Bakirlitepe,
TUBITAK National Observatory, Turkey) using the TFOSC instrument.
We obtained series of Rc exposures in July 05, 2018 (6 frames x 600
sec, UT = 19:12 - 20:19), ~ 4 hours after the burst. Within enhanced
Swift-XRT position (Goad et al., GCN 22906) we have not detected any
object down to Rc =~ 23.5 mag in the combined image (calibrated
against SDSS secondary standard stars). Our result confirms OT
non-detections as published in other GCNs (Lipunov et al., GCN 22904,
Watson et al., GCN 22911, Breeveld et al., GCN 22912, Mazaeva et al.,
GCN 22913).
GCN Circular 22920
Subject
GRB 180705A: Swift-XRT refined Analysis
Date
2018-07-06T17:10:02Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), D.N. Burrows (PSU), A.
Tohuvavohu (PSU), S. J. LaPorte (PSU), K.L. Page (U. Leicester), A.P.
Beardmore (U. Leicester), P.A. Evans (U. Leicester), V. D'Elia (ASDC)
and M. Stamatikos report on behalf of the Swift-XRT team:
We have analysed 5.7 ks of XRT data for GRB 180705A (Stamatikos et al.
GCN Circ. 22902), from 3.4 ks to 56.6 ks after the BAT trigger. The
data comprise 1.1 ks in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Goad et al. (GCN Circ. 22906).
The light curve can be modelled with a power-law decay with a decay
index of alpha=1.12 (+0.17, -0.13).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.99 (+0.32, -0.30). The
best-fitting absorption column is 3.9 (+1.8, -1.5) x 10^21 cm^-2, in
excess of the Galactic value of 5.8 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 3.9 x 10^-11 (6.0 x 10^-11) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 3.9 (+1.8, -1.5) x 10^21 cm^-2
Galactic foreground: 5.8 x 10^20 cm^-2
Excess significance: 3.7 sigma
Photon index: 1.99 (+0.32, -0.30)
If the light curve continues to decay with a power-law decay index of
1.12, the count rate at T+24 hours will be 6.4 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.5 x
10^-13 (3.8 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/00846299.
This circular is an official product of the Swift-XRT team.
GCN Circular 22913
Subject
GRB 180705A: TSHAO optical upper limit
Date
2018-07-06T11:29:42Z (7 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Pozanenko (IKI), A. Kusakin (FAPHI), I. Reva
(FAPHI), A. Volnova (IKI), M. Krugov (FAPHI) report on behalf of larger
GRB follow-up collaboration:
We observed the field of GRB 180705A (Stamatikos et al., GCN 22902)
with Zeiss-1000 1-m telescope of Tien Shan Astronomical Observatory
starting on July 05 (UT) 16:13:52. We obtained several images in
R-filter. Within enhanced XRT Swift-XRT position (Goad et al., GCN
22906) we do not detect any object. Preliminary photometry of the
field is following.
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2018-07-05 16:13:52 0.04895 R 25*120 n/d n/d 21.3
The photometry is based on several nearby SDSS-DR12 stars.
Ref.stars
SDSS-DR12_id R(Lupton)
J141030.67-113927.0 17.460
J141015.17-113809.7 17.680
GCN Circular 22912
Subject
GRB 180705A: Swift/UVOT Upper Limits
Date
2018-07-06T10:11:35Z (7 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL), S. W. K Emery (UCL-MSSL) and M. Stamatikos
(OSU/NASA/GSFC) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 180705A
3368 s after the BAT trigger (Stamatikos et al., GCN Circ. 22902).
No optical afterglow consistent with the enhanced XRT position (Goad et
al. GCN Circ. 22906) 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
white_FC 3368 3485 115 >20.2
white 3368 5327 312 >20.8
v 4103 5738 393 >18.9
b 4923 11649 311 >20.5
u 4718 11527 1082 >21.0
w1 4513 16889 483 >20.5
m2 4308 15205 647 >20.1
w2 5333 5533 197 >20.4
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.06 in the direction of the
burst (Schlegel et al. 1998).
GCN Circular 22911
Subject
GRB 180705A: RATIR Optical Observations
Date
2018-07-06T09:19:42Z (7 years ago)
From
Alan M. Watson at Instituto de Astronomia UNAM <alan@astro.unam.mx>
Alan M. Watson (UNAM), Nat Butler (ASU), Alexander Kutyrev (GSFC),
William H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J.
Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI),
Eleonora Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz
(UCSC), Jes��s Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey
Moseley (GSFC), John Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki
Toy (UMD) report:
We observed the field of GRB 180705A (Stamatikos et al., GCN Circ.
22902) 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 2018/07 6.16 to
2018/07 6.27 UTC (12.19 to 14.82 hours after the BAT trigger), obtaining
a total of 1.74 hours exposure in the r and i bands.
For a source within the Swift-XRT error circle (Kennea et al., GCN Circ.
22903), in comparison with the SDSS DR9 catalog, we obtain the following
3-sigma upper limits:
r > 23.20
i > 23.07
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.
GCN Circular 22907
Subject
GRB 180705A: Swift-BAT refined analysis
Date
2018-07-06T03:32:53Z (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), 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-239 to T+963 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 180705A (trigger #846299)
(Stamatikos et al., GCN Circ. 22902). The BAT ground-calculated position is
RA, Dec = 212.605, -11.640 deg which is
RA(J2000) = 14h 10m 25.1s
Dec(J2000) = -11d 38' 23.7"
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 36%.
The mask-weighted light curve shows some weak emission that starts at ~T0 and
ends at ~T+130 s. However, the burst went out of the BAT FOV from T+158 s to
T+204 s due to a preplanned slew, and thus there might be additional
emission when the burst was out of the FOV. The burst came back in the BAT FOV
shortly during the slew period (from T0+205 s to T0+262 s), though no emission
are found during this time. T90 (15-350 keV) is 123.2 +- 16.6 sec (estimated
error including systematics).
The time-averaged spectrum from T+0.26 to T+133.70 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.63 +- 0.22. The fluence in the 15-150 keV band is 2.0 +- 0.3 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+3.60 sec in the 15-150 keV band
is 0.7 +- 0.3 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/846299/BA/
GCN Circular 22906
Subject
GRB 180705A: Enhanced Swift-XRT position
Date
2018-07-05T19:08:58Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester)
report on behalf of the Swift-XRT team.
Using 1348 s of XRT Photon Counting mode data and 4 UVOT
images for GRB 180705A, 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 = 212.61323, -11.64745 which is equivalent
to:
RA (J2000): 14h 10m 27.17s
Dec (J2000): -11d 38' 50.8"
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 22904
Subject
GRB 180705A: MASTER optical observation
Date
2018-07-05T18:08:43Z (7 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tiurina, A.Kuznetsov, V.Chazov,
I. Gorbunov, D. Vlasenko, D.Zimnukhov, D.Kuvshinov, P.Balanutsa, V.Vladimirov
Lomonosov Moscow State University,SAI
D. Buckley,
South African Astronomical Observatory (SAAO)
R. Rebolo, M. Serra, N. Lodieu, G. Israelian, L. Suarez-Andres
The Instituto de Astrofisica de Canarias (IAC)
A. Tlatov, V.Senik, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory
R. Podesta, F. Podesta, C. Lopez, C.Francile
Observatorio Astronomico Felix Aguilar (OAFA)
H.Levato,
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
O. Gres, N.M.Budnev , Yu.Ishmuhametova
Irkutsk State University (ISU)
A. Gabovich, V. Yurkov, Yu. Sergienko
Blagoveschensk Educational State University (BSPU)
MASTER-SAAO robotic telescope (MASTER-Net: http://observ.pereplet.ru Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) ,
located in South African Astronomical Observatory,
was pointed to the Swift GRB180705A (BAT: Stamatikos et al. GCN 22902, GRBtime: 2018-07-05 15:41:14UT; XRT : RA,Dec2000=14h 10m 27.18s -11d 38' 54.3" Kennea et al. GCN22903)
at 2018-07-05 15:54:52 ( GRB Altitude: 55.90, Sun: Altitude: -3.10) at sunset.
So MASTER-SAAO started GRB180705A observations at 2018-07-05 16:35:54UT (GRB altitute: 62.78, Sun: Altitude: -11.10).
MASTER automatic unfiltered (W=0.2B+0.8R by USNO-B1) limits are the following
T_start,UT Exp,s mlim MASTER-II
2018-07-05 16:35:54 540 18.8 WEST
2018-07-05 16:35:54 180 17.9 WEST
2018-07-05 16:35:59 540 18.3 EAST
2018-07-05 16:35:59 180 17.5 EAST
2018-07-05 16:39:32 180 18.2 WEST
2018-07-05 16:39:37 180 17.9 EAST
2018-07-05 16:44:51 180 18.7 WEST
2018-07-05 16:44:56 180 18.4 EAST
2018-07-05 16:48:21 540 19.7 WEST
2018-07-05 16:48:21 180 18.8 WEST
2018-07-05 16:48:25 540 19.5 EAST
2018-07-05 16:48:25 180 18.5 EAST
2018-07-05 16:51:52 180 19.0 WEST
2018-07-05 16:51:56 180 18.8 EAST
2018-07-05 16:55:26 180 19.0 WEST
2018-07-05 16:55:30 180 18.8 EAST
2018-07-05 16:58:59 540 19.9 WEST
2018-07-05 16:58:59 180 19.3 WEST
2018-07-05 16:59:04 540 19.7 EAST
2018-07-05 16:59:04 180 19.0 EAST
2018-07-05 17:02:29 180 19.3 WEST
2018-07-05 17:02:34 180 19.0 EAST
2018-07-05 17:05:58 180 19.3 WEST
2018-07-05 17:06:03 180 19.0 EAST
2018-07-05 17:09:33 540 20.0 WEST
2018-07-05 17:09:33 180 19.3 WEST
2018-07-05 17:09:37 540 19.6 EAST
2018-07-05 17:09:37 180 19.0 EAST
2018-07-05 17:13:06 180 19.3 WEST
2018-07-05 17:13:10 180 19.1 EAST
2018-07-05 17:16:51 180 19.3 WEST
2018-07-05 17:16:56 180 19.0 EAST
2018-07-05 17:20:25 180 19.3 WEST
2018-07-05 17:20:29 180 19.0 EAST
The message may be cited.
GCN Circular 22903
Subject
GRB 180705A: Swift-XRT observations
Date
2018-07-05T17:10:37Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
J.A. Kennea (PSU), G. Tagliaferri (INAF-OAB), S. Campana (INAF-OAB),
P.A. Evans (U. Leicester), J.P. Osborne (U. Leicester) and D.N. Burrows
(PSU) report on behalf of the Swift-XRT team:
The XRT began observing the field of GRB 180705A at 16:37:18.4 UT,
3363.7 seconds after the BAT trigger. Using promptly downlinked data we
find an uncatalogued X-ray source located at RA, Dec 212.61326,
-11.64841 which is equivalent to:
RA(J2000) = 14h 10m 27.18s
Dec(J2000) = -11d 38' 54.3"
with an uncertainty of 4.3 arcseconds (radius, 90% containment). This
location is 94 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. No
spectrum from the promptly downlinked event data is yet available to
determine the column density.
GCN Circular 22902
Subject
GRB 180705A: Swift detection of a burst
Date
2018-07-05T15:55:08Z (7 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
M. Stamatikos (OSU/NASA/GSFC), S. D. Barthelmy (GSFC),
A. A. Breeveld (UCL-MSSL), A. D'Ai (INAF-IASFPA), V. D'Elia (ASDC),
A. Deich (PSU), S. W. K Emery (UCL-MSSL), J.D. Gropp (PSU),
J. A. Kennea (PSU), N. P. M. Kuin (UCL-MSSL),
F. E. Marshall (NASA/GSFC), D. M. Palmer (LANL), B. Sbarufatti (PSU)
and M. H. Siegel (PSU) report on behalf of the Neil Gehrels Swift
Observatory Team:
At 15:41:14 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 180705A (trigger=846299). Swift did not slew due to an observing
constraint. The BAT on-board calculated location is
RA, Dec 212.594, -11.630, which is
RA(J2000) = 14h 10m 23s
Dec(J2000) = -11d 37' 48"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). As is typical for image triggers, the real-time light
curve does not show anything significant. The image trigger significance is 7.8
sigma, therefore we have high confidence in this event.
Due to an observing constraint, Swift will not slew until T0+54
minutes. There will be no XRT or UVOT data until this time.
Burst Advocate for this burst is M. Stamatikos (Michael.Stamatikos-1 AT nasa.gov).
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.)