GRB 160410A
GCN Circular 19311
Subject
GRB 160410A: SMARTS optical/IR observations
Date
2016-04-13T02:55:57Z (10 years ago)
From
Bethany Cobb at GWU <bcobb@gwu.edu>
B. E. Cobb (GWU) reports:
Using the ANDICAM instrument on the 1.3m telescope at CTIO, we
obtained optical/IR imaging of the error region of GRB 160410A
(GCN 19271, Gibson et al.) with a mid-exposure time of 20.7 hours
post-burst (2016-04-11 01:49 UT). Total summed exposure times
amounted to 36 minutes in I and 30 minutes in J.
No source is detected at the position of the optical
afterglow (e.g. GCN 19271, Gibson et al.; GCN 19272, Yates
et al.) to approximate limiting magnitudes of I > 20.3 and J > 17.5.
Magnitudes are calibrated using USNO-B1.0 stars in I,
and 2MASS stars in J.
GCN Circular 19309
Subject
GRB 160410A: TLS Tautenburg observations
Date
2016-04-12T21:16:50Z (10 years ago)
From
Sebastian Schmidl at TLS Tautenburg <schmidl@tls-tautenburg.de>
I. Juvan (IWF Graz), M. Bluemcke, D. Baak (University of Jena), S. Kunz,
S. Schmidl, S. Klose, D. A. Kann, A. Nicuesa Guelbenzu, and F. Ludwig
(TLS Tautenburg) report:
We observed the field of GRB 160410A (Gibson et al., GCN 19271) with
the Tautenburg 1.34-m Schmidt telescope at a mid-time of about 14.6 hrs
after the GRB trigger, at a mean airmass of 1.5. We obtained 4 x 300s
and 1 x 600s exposures in the Ic band.
We do not detect the optical afterglow reported by Gibson et al. (GCN
19271), Yates et al. (GCN 19272), Selsing et al. (GCN 19274), Trotter et
al. (GCN 19277), Wang et al. (GCN 19280) and Klotz et al (GCN 19287).
We estimate a preliminary upper limit of Ic > 21.1 mag (AB magnitude
system), calibrated against SDSS field stars.
These observations were performed as part of the Tautenburg Observing
School at the Thueringer Landessternwarte.
GCN Circular 19306
Subject
GRB 160410A: JCMT SCUBA-2 sub-mm observation
Date
2016-04-12T19:25:53Z (10 years ago)
From
Ian Smith at Rice U <ian@spacsun.rice.edu>
I.A. Smith (Rice U.), N.R. Tanvir (U. of Leicester), and Y. Urata (NCU)
report:
We observed the location of the short GRB 160410A (Gibson et al.,
GCN Circ. 19271) using the SCUBA-2 sub-millimeter continuum camera
on the James Clerk Maxwell Telescope. The observation started at
05:54 UT on 2016-04-10, corresponding to 45 minutes after the burst
trigger. Exposures totaling 2.0 hours were made in good weather
conditions. No source was detected, with the RMS background noise
being 1.3 mJy/beam at 850 microns and 12.5 mJy/beam at 450 microns.
We thank Callie Matulonis, Lianghao Lin, and Iain Coulson for the prompt
support of these observations that were taken under project M16AP005.
GCN Circular 19300
Subject
GRB 160410A: further NOT optical observations
Date
2016-04-12T12:35:22Z (10 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
D. Malesani (DARK/NBI), D. Xu (NAOC/CAS), T. Kuutma (NOT and Tartu
Obs.), report on behalf of a larger collaboration:
We observed again the optical counterpart of GRB 160410A (Gibson et al.,
GCN 19271) with the Nordic Optical Telescope (NOT) equipped with ALFOSC.
Observations started on April 11.87 UT and consisted of 4x900 s
exposures in the SDSS r band.
At a mid time of 40.37 hr after the GRB, we do not detect any longer the
optical afterglow down to a 3-sigma limiting magnitude of r > 25 (AB),
calibrated against nearby SDSS stars. The corresponding decay index (F
propto t^-alpha) between our two NOT observations (Malesani &
Kirkpatrick, GCN 19925) is constrained to be alpha > 0.9. The object
closest to the GRB position (with r ~ 24) lies 4.7" away, so we cannot
single out any obvious host galaxy candidate to the GRB, down to the
quoted limiting magnitude.
GCN Circular 19295
Subject
GRB 160410A: NOT observations of the afterglow
Date
2016-04-11T21:27:08Z (10 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
D. Malesani (DARK/NBI) and C. Kirkpatrick (Univ. Helsinki) report on
behalf of a larger collaboration:
We observed the optical counterpart of GRB 160410A (Gibson et al., GCN
19271) with the Nordic Optical Telescope (NOT) equipped with ALFOSC.
Observations started on April 10.92 UT and consisted of 3x900 s
exposures in the SDSS r band.
The optical counterpart of GRB 160410A is well detected with a magnitude
r = 24.15 +- 0.09 (AB), calibrated against nearby SDSS stars, at a mean
epoch April 10.936 UT (17.3 hr after the GRB). The source looks
pointlike in our images (with a seeing of 0.65").
GCN Circular 19290
Subject
GRB 160410A: UKIRT near-IR upper limits
Date
2016-04-11T17:24:13Z (10 years ago)
From
Wen-fai Fong at U of Arizona <wfong@email.arizona.edu>
W. Fong and P. Milne (University of Arizona) report:
"We observed the field of the short-duration GRB 160410A (Gibson et al.,
GCN 19271) with the Wide Field Camera (WFCAM) mounted on the 3.8-m United
Kingdom Infrared Telescope (UKIRT) on Mauna Kea beginning on 2016 Apr
11.215 UT (25.3 hr post-burst). We obtained observations in the J- and
K-bands in 0.7" seeing. Using the quick-look pipeline ORAC-DR, we do not
detect any near-IR source in or around the positions of the X-ray
(Beardmore et al., GCN 19273) or optical (Yates et al., GCN 19272; Selsing
et al., GCN 19274; Marshall et al., GCN 19275; Trotter et al., GCN 19277)
afterglows. Calibrated to 2MASS, we therefore place 3-sigma limits of
J(AB)>20.0 mag and K(AB)>19.5 mag on the near-IR afterglow of GRB 160410A
at 25.3 hr post-burst. We note that this analysis is preliminary and a
final reduction of the images are expected to be ~1.5 mag deeper.
We thank Sam Benigni for executing these observations. In addition, we
thank Watson Varricatt, Tom Kerr, and Richard Green for their assistance in
re-establishing a system for a target-of-opportunity program at UKIRT."
GCN Circular 19288
Subject
Konus-Wind observation of GRB 160410A (short/hard)
Date
2016-04-11T14:38:02Z (10 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov,
D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline,
on behalf of the Konus-Wind team, report:
The short GRB 160410A (Swift/BAT observation:
Gibson et al., GCN 19271; Sakamoto et al., GCN 19276)
triggered Konus-Wind at T0=18592.644 s UT (05:09:52.644).
The light curve shows a short, hard pulse with a total duration is ~2 s.
The emission is seen up to ~4 MeV.
As observed by Konus-Wind, the burst had a fluence of
(1.20 �� 0.3)x10^-5 erg/cm2 and a 16-ms peak energy flux,
measured from T0-0.016, of (2.8 �� 0.4)x10^-5 erg/cm2
(both in the 20 keV - 10 MeV energy range).
The spectrum of the burst (measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 10 MeV range by a cutoff power-law
(CPL) function with the following model parameters:
the photon index alpha = -0.71(-0.20,+0.26),
and the peak energy Ep = 1416(-356,+528) keV,
chi2 = 92/97 dof.
Fitting this spectrum with the GRB (Band) function yields
the same alpha and Ep with only an upper limit on beta of -2.1,
chi2 = 92/96 dof.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160410_T18592/
Assuming the redshift z=1.717 (Selsing et al., GCN 19274)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, and Omega_Lambda = 0.73,
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is ~4.0x10^52 erg,
the peak luminosity L_iso is ~7.5x10^52 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is ~4660 keV.
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.
GCN Circular 19287
Subject
GRB 160410A: TAROT La Silla observatory early optical observations
Date
2016-04-11T13:13:27Z (10 years ago)
From
Alain Klotz at IRAP-CNRS-OMP <Alain.Klotz@free.fr>
Klotz A., Turpin D., Atteia J.L. (CNRS-OMP-IRAP),
Boer, M., Laugier, R. (CNRS-ARTEMIS),
Gendre B. (UVI - Etelman Obs.) report:
We imaged the field of GRB 160410A detected by SWIFT
(trigger 682269) with the TAROT robotic telescope (D=25cm)
located at the European Southern Observatory,
La Silla observatory, Chile.
The observations started 28s after the GRB trigger
(16.8s after the notice). Due to a technical problem
only the first exposure of 60s was taken.
The image is trailed (see the description in Klotz
et al., 2006, A&A 451, L39). We detect the UVOT
optical transcient discovered by Gibson et al. (GCNC 19271).
At the beginning of the trail (t0+28s) the magnitude is
R=18.4 (+/-0.3) and decays to R=18.7 (limiting magnitude)
at t0+46s. Then the OT became too faint to be detected
between t0+46 and t0+88s (Rlim=18.7).
Magnitudes were estimated with the nearby NOMAD1 stars
and are not corrected for galactic dust extinction.
GCN Circular 19285
Subject
GRB 160410A: MITSuME Akeno optical upper limits
Date
2016-04-11T09:43:58Z (10 years ago)
From
Taketoshi Yoshii at Tokyo Tech <yoshii.t.ac@m.titech.ac.jp>
Y. Muraki, Y.Ono, T.Fujiwara, T. Yoshii, Y. Saito, Y. Tachibana,
H. Ohuchi, Y. Yano, S.Harita, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 160410A (S. L. Gibson et al., GCN Circular #19271) with the
optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 2016-04-10 12:06:25 UT (~7.1 h after the burst).
We did not find any new point source within XRT circle in all three bands.
We obtained following limits for the magnitudes.
T0+[hour] MID-UT T-EXP[sec] g' Rc Ic
----------------------------------------------------------------------------
7.1 13:24:39 4694 >19.8 >19.7 >19.1
----------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.
GCN Circular 19282
Subject
GRB 160410A: Swift-XRT refined Analysis
Date
2016-04-11T05:36:03Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
B. Sbarufatti (INAF-OAB/PSU), K.L. Page (U. Leicester), C. Pagani (U.
Leicester), A.P. Beardmore (U. Leicester), A. Maselli (INAF-IASFPA),
A. Melandri (INAF-OAB), P. D'Avanzo (INAF-OAB), D.N. Burrows (PSU),
T.G.R. Roegiers (PSU) and S.L. Gibson report on behalf of the Swift-XRT
team:
We have analysed 5.7 ks of XRT data for GRB 160410A (Gibson et al. GCN
Circ. 19271), from 72 s to 67.9 ks after the BAT trigger. The data
comprise 241 s in Windowed Timing (WT) mode (the first 9 s were taken
while Swift was slewing) with the remainder in Photon Counting (PC)
mode. The enhanced XRT position for this burst was given by Beardmore
et al. (GCN Circ. 19273).
The light curve can be modelled with a power-law decay with a decay
index of alpha=1.54 (+/-0.11).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.28 (+0.12, -0.06). The
best-fitting absorption column is consistent with the Galactic value
of 1.8 x 10^20 cm^-2 (Willingale et al. 2013). The PC mode spectrum has
a photon index of 1.9 (+0.8, -0.5) and a best-fitting absorption column
of 2 (+34, -2) x 10^21 cm^-2. The counts to observed (unabsorbed)
0.3-10 keV flux conversion factor deduced from this spectrum is 3.5 x
10^-11 (3.8 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Galactic foreground: 1.8 x 10^20 cm^-2
Intrinsic column: 2 (+34, -2) x 10^21 cm^-2 at z=1.717
Photon index: 1.9 (+0.8, -0.5)
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00682269.
This circular is an official product of the Swift-XRT team.
GCN Circular 19280
Subject
GRB 160410A: GMG observation
Date
2016-04-11T02:42:04Z (10 years ago)
From
Jirong Mao at Yunnan Obs <jirongmao_obs@ynao.ac.cn>
C.-J. Wang, J. Mao, and J.-M. Bai (YNAO) report:
We observed the field of GRB 160410A (Gibson et al., GCN 19271) with the 2.4-meter optical telescope at Gao-Mei-Gu (GMG)
station of Yunnan Observatories. Observations began from 12:40:10 UT, Apr. 10th, 2016, about 7.5 hours after the trigger.
We marginallydetected one faint source in the image at the afterglow position (Yates et al. GCN 19272), and the magnitude was
estimated as R~22.1+/- 0.2 mag.
GCN Circular 19278
Subject
GRB 160410A: Keck-I/LRIS redshift
Date
2016-04-10T20:53:26Z (10 years ago)
From
Yi Cao at Caltech <ycao@astro.caltech.edu>
Yi Cao, S. R. Kulkarni, Lin Yan, Vikram Ravi, H. K. Vedantham, Mansi M.
Kasliwal (Caltech)
We obtained a spectrum of the optical afterglow of GRB 160410A with the Low
Resolution Imaging Spectrometer (LRIS) on the Keck-I telescope at Mauna
Kea, following the Swift UVOT localization (GCN 19271). Our spectroscopic
integration started 84.25 minutes after the Swift trigger at airmass 1.05
and one 600s spectrum was obtained covering 3100-10200 Angstrom.
Our spectrum reveals a blue continuum superposed by a strong and broad
absorption around centered around 3300 Angstrom as well as a number of weak
and narrow absorption features. Upon obtaining the data we determined a
redshift of 1.72 based primarily on the broad damped Lyman alpha and
threshold detection of narrow Si II, O I, C IV and Mg II absorption lines.
Our redshift is consistent to that derived from the VLT/X-shooter spectra
(GCN 19274).
GCN Circular 19277
Subject
GRB 160410A: Skynet PROMPT-CTIO observations of the optical afterglow
Date
2016-04-10T20:43:16Z (10 years ago)
From
Adam S. Trotter at UNC-Chapel Hill/PROMPT/Skynet <atrotter@physics.unc.edu>
A. Trotter, D. Reichart, J. Haislip, J. Moore, N. Frank, M. Maples, E. Johnson, R. Joyner, J. Martin, C. Salemi, J. A. Crain, K. Ivarsen, A. LaCluyze, and M. Nysewander report:
Skynet observed the Swift BAT/XRT localization of GRB 160410A (Gibson et al., GCN 19271, Swift trigger=682269) with with one 16" telescope (P5), and two 24" telescopes (P1, P8) of the PROMPT array at CTIO, Chile. Starting at 2016-04-10 05:10:36 UT and continuing until 05:54 UT (t=48s-45m post-trigger), Skynet took a total of 93 exposures ranging from 5-160s in the I band (P1, P5) and the B band (P8).
We detect a fading optical afterglow in individual and stacked I-band images at the position first reported by Gibson et al. (GCN 19271) and Yates et al. (GCN 19272), with I~17.3 at t=1m and I~19.4 at t=6m.
A preliminary light curve is at:
http://www.skynet.unc.edu/grb/grb160410a.png
Magnitudes are in the Vega System, calibrated to 4 APASS DR9 stars in the field. Magnitudes have not been corrected for line-of-sight Milky Way dust extinction, with expected E(B-V)=0.02 (Schlafly & Finkbeiner 2011).
No further Skynet observations are scheduled.
GCN Circular 19276
Subject
GRB 160410A: Swift-BAT refined analysis of the short GRB
Date
2016-04-10T17:41:10Z (10 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), S. L. Gibson (U Leicester), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), J. P. Norris (BSU),
D. M. Palmer (LANL), M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
Using the data set from T-60 to T+243 sec from the recent telemetry downlinks,
we report further analysis of BAT short GRB 160410A (trigger #682269)
(Gibson, et al., GCN Circ. 19271). The BAT ground-calculated position is
RA, Dec = 150.695, 3.461 deg, which is
RA(J2000) = 10h 02m 46.9s
Dec(J2000) = +03d 27' 40.3"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 37%.
The mask-weighted light curve shows an initial spike starting at ~T-0.2 s
peaking at ~T+0.1 s with a decay out to ~T+2.5 s, then a greatly reduced
flux level portion out to ~T+9 s. T90 (15-350 keV) is 8.2 +- 1.6 s
(estimated error including systematics).
The time-averaged spectrum from T+0.04 to T+9.60 s is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
0.93 +- 0.17. The fluence in the 15-150 keV band is 7.8 +- 0.8 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.04 sec in the 15-150 keV band
is 3.5 +- 0.3 ph/cm2/s. 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/682269/BA/
Using a 4-ms binned light curve for this bright burst, the lag of the initial pulse
(~T0 to ~T0+2 s) for the 100-350 keV to 25-50 keV bands is -3 (+/-7) ms
(with 1-sigma error) and for the 50-100 kev to 15-25 keV bands the lag is 8 (+/-14) ms.
These values are consistant with zero, thus confirming that this is a short GRB.
There is extended emission out to ~T+10 sec at ~0.038 counts/det/sec then dropping
to ~0.0055 counts/det/sec out to ~T+92 sec.
GCN Circular 19275
Subject
GRB 160410A: Swift/UVOT Detection
Date
2016-04-10T17:40:46Z (10 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) and S. L. Gibson (U. Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160410A
91 s after the BAT trigger (Gibson et al., GCN Circ. 19271).
A source consistent with the initial UVOT position
(Gibson et al. GCN Circ. 19271), the enhanced XRT position
(Beardmore et al. GCN Circ. 19273), and the GROND position
(Yates et al. GCN Circ. 19272)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 10:02:44.37 = 150.68488 (deg.)
Dec (J2000) = +03:28:42.7 = 3.47853 (deg.)
with an estimated uncertainty of 0.49 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 91 241 147 19.46 +/- 0.10
v 4867 6503 393 >19.7
b 4251 5887 393 >20.2
u 304 12411 866 20.50 +/- 0.20
w1 5277 11801 1082 >20.3
m2 5072 10893 1082 >20.8
w2 4662 6298 393 >20.5
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).
GCN Circular 19274
Subject
GRB 160410A: VLT/X-shooter redshift
Date
2016-04-10T15:50:03Z (10 years ago)
From
Daniele Malesani at Dark Cosmology Centre, Niels Bohr Inst <malesani@dark-cosmology.dk>
J. Selsing (DARK/NBI), P.M. Vreeswijk (WIS), J. Japelj (INAF/OATs), V.
D'Elia (ASI/ASDC and INAF/Roma), A. de Ugarte Postigo (IAA/CSIC and
DARK/NBI), G. Pugliese (API/UvA), D. Xu (NAOC/CAS), D. Malesani
(DARK/NBI), T. Kruehler (MPE), J.P.U. Fynbo (DARK/NBI), report on behalf
of a larger collaboration:
We observed the optical afterglow of GRB 160410A (Gibson et al., GCN
19271; Yates et al., GCN 19272) with the ESO Very Large Telescope UT2
(Kueyen) equipped with X-shooter. Observations were triggered
robotically in "rapid response mode" (RRM). Our spectroscopic
integration started 8.4 min after the GRB and 3x600 s spectra were
collected covering the wavelength range 3000-24,500 AA, until the target
became too low on the horizon.
The optical afterglow is detected in our acquisition image (7.7 min
after the GRB) with a magnitude r = 20.29 +- 0.06 (AB), calibrated
against two nearby SDSS stars.
Our spectra reveal continuum over the entire spectral range redward of
~3400 AA, which constrains the redshift to be z < 1.8. Besides, a number
of weak absorption features are detected, which we interpret as due to
Fe II and Al II at a redshift z = 1.717. At this redshift, the Mg II
2796,2803 doublet lies into a region of strong telluric absorption (the
A band) and is not detected. Two intervening C IV absorbers are also
observed at z = 1.444 and z = 1.581.
We acknowledge excellent and prompt support from the ESO staff at
Paranal, in particular Annalisa De Cia and Cedric Ledoux.
GCN Circular 19273
Subject
GRB 160410A: Enhanced Swift-XRT position
Date
2016-04-10T12:39:51Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester)
report on behalf of the Swift-XRT team.
Using 380 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 160410A, 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 = 150.68560, +3.47856 which is equivalent
to:
RA (J2000): 10h 02m 44.54s
Dec (J2000): +03d 28' 42.8"
with an uncertainty of 3.0 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 19272
Subject
GRB 160410A: GROND optical detection
Date
2016-04-10T06:34:19Z (10 years ago)
From
Robert Yates at MPE/Swift <robyates@mpe.mpg.de>
R Yates (MPE Garching) , T Kruehler (MPE Garching), J Greiner (MPE
Garching) report on behalf of the GROND team:
We observed the field of GRB 160410A (Swift trigger 682269; Gibson et al.,
GCN #19271) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008,
PASP 120, 405) mounted at the 2.2 m MPG telescope at ESO La Silla
Observatory (Chile).
Observations started at 05:42 UT on 10-04-2016, 32mins after the GRB
trigger. They were performed at an average seeing of 1.8" and at an
average airmass of 2.7.
We found a single point source within the 0.7" Swift-UVOT error circle
reported by Gibson et al. (GCN #19271) at
RA (J2000.0) = 10h 02m 44.37s
DEC (J2000.0) = +03d 28' 42.4"
with an uncertainty of 0.5" in each coordinate.
Based on the first 4 min of total exposures in g'r'i'z' and JHK, we
estimate preliminary magnitudes (all in AB system) of
g' = 20.6 +/- 0.1 mag,
r' = 20.5 +/- 0.1 mag,
i' = 20.7 +/- 0.1 mag,
z' = 20.5 +/- 0.2 mag,
J > 20.0 mag,
H > 19.6 mag, and
K > 18.0 mag.
Given magnitudes are calibrated against SDSS/2MASS zeropoints as well as
2MASS field stars and are not corrected for the expected Galactic
foreground extinction corresponding to a reddening of E_(B-V)=0.0180 mag
in the direction of the burst (Schlafly & Finkbeiner 2011).
GCN Circular 19271
Subject
GRB 160410A: Swift detection of a (possibly-short) burst with an optical counterpart
Date
2016-04-10T05:35:57Z (10 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
S. L. Gibson (U Leicester), D. Malesani (DARK/NBI),
K. L. Page (U Leicester), D. M. Palmer (LANL) and M. H. Siegel (PSU)
report on behalf of the Swift Team:
At 05:09:48 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 160410A (trigger=682269). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 150.681, +3.443 which is
RA(J2000) = 10h 02m 43s
Dec(J2000) = +03d 26' 37"
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 2 sec. The peak count rate
was ~9000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 05:11:10.9 UT, 82.9 seconds after
the BAT trigger. XRT found a bright, uncatalogued X-ray source located
at RA, Dec 150.6857, 3.4782 which is equivalent to:
RA(J2000) = +10h 02m 44.57s
Dec(J2000) = +03d 28' 41.5"
with an uncertainty of 5.6 arcseconds (radius, 90% containment). This
location is 127 arcseconds from the BAT onboard position, within the
BAT error circle. No event data are yet available to determine the
column density using X-ray spectroscopy.
The initial flux in the 2.5 s image was 1.04e-09 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 91 seconds after the BAT trigger. There is a candidate afterglow in
the rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 10:02:44.39 = 150.68494
DEC(J2000) = +03:28:42.9 = 3.47858
with a 90%-confidence error radius of about 0.78 arc sec. This position is 3.0
arc sec. from the center of the XRT error circle. The estimated magnitude is
19.49 with a 1-sigma error of about 0.16. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.02.
Burst Advocate for this burst is S. L. Gibson (slg44 AT le.ac.uk).
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.)