GRB 140606B
GCN Circular 16363
Subject
GRB 140606B: Fermi GBM detection
Date
2014-06-07T16:05:57Z (11 years ago)
From
Eric Burns at U of Alabama <EricKayserBurns@gmail.com>
E. Burns (UAH) reporting on behalf of the Fermi GBM Team:
"At 03:11:51.86 UT on 06 June 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 140606B (trigger 423717114 / 140606133).
The on-ground calculated location, using the GBM trigger
data, is RA = 327.9, DEC = +33.7 (J2000 degrees,
equivalent to 21 h 51 m, 33 d 41 '), with an uncertainty
of 1.00 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 66 degrees.
The optical afterglow candidates reported by iPTF (Singer et al.
GCN 16360) lie within the 1-sigma (statistical and systematic)
uncertainty regions surrounding the GBM localization.
The GBM light curve shows one long peak with a
noisy tail with a duration (T90) of about 23.6 s (50-300 keV).
The time-averaged spectrum from T0-3.0 s to T0+12.3 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.22 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 473.00 +/- 82.60 keV
The event fluence (10-1000 keV) in this time interval is
(9.018 +/- 0.369)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.58 s in the 10-1000 keV band is
13.31 +/- 0.37 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
GCN Circular 16365
Subject
GRB 140606B / Fermi 432717114 / iPTF 14bfu: Keck redshift
Date
2014-06-08T02:09:34Z (11 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley, Y. Cao (Caltech), M. Kasliwal (Carnegie), and E. Kirby
(UCI) report:
On the night of 2014-06-07 starting at 19:16 (UT) we acquired two 900
second optical spectra of iPTF14bfu (Singer et al., GCN 16360), an
optical transient in the error circle of GRB 140606B / Fermi 432717114
(Burns et al., GCN 16360), with the DEIMOS spectrograph on the Keck II
10 meter telescope.
In the reduced spectrum of this object we identify emission lines from
OII, OIII (5007) and H-alpha, as well as absorption features from Ca II
(H+K), at a consistent redshift of z = 0.384. A serendipitous galaxy
offset by ~2 arcseconds (10 kpc) along the slit shows the same emission
lines at identical redshift but no detectable continuum.
Given this redshift, the high luminosity inferred for the optical
transient at the time of the initial detection (absolute magnitude ~
-21.7) favors the association of this source as the optical afterglow of
GRB 140606B.
GCN Circular 16366
Subject
GRB 140606B: Swift XRT position
Date
2014-06-08T15:34:22Z (11 years ago)
From
Vanessa Mangano at PSU <vanessa@ifc.inaf.it>
V. Mangano (PSU), P.A. Evans and M.R. Goad (U. Leicester) report
on behalf of the Swift-XRT team:
We have analysed 5 ks of XRT data for the Fermi/GBM-detected burst:
GRB 140606B, from 184.4 ks to 192.6 ks after the Fermi/GBM trigger.
The data are entirely in Photon Counting (PC) mode.
Using 4979 s of XRT Photon Counting mode data and 4 UVOT
images, 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 =
328.12501, 32.01458 which is equivalent to:
RA (J2000): 21 52 30.00
Dec (J2000): +32 00 52.5
with an uncertainty of 2.3 arcsec (radius, 90% confidence).
This position is a 5.2 arcsec from source iPTF 14bfu from
GCN Circular 16360.
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).
We cannot determine at the present time whether the source is fading.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00020384.
This circular is an official product of the Swift-XRT team.
GCN Circular 16367
Subject
GRB140606B/iPTF14bfu: Discovery Channel Telescope Optical Detection
Date
2014-06-08T18:57:35Z (11 years ago)
From
Vicki Toy at UMD <vtoy@astro.umd.edu>
V. Toy (UMD), J. Capone (UMD), D. Kocevski (NASA-GSFC), S.B. Cenko
(NASA-GSFC), A. Cucchiara (NASA-GSFC), E. Troja (NASA-GSFC), A. Kutyrev
(NASA-GSFC), S. Veilleux (UMD), and S. Gezari (UMD) report on behalf of a
larger collaboration:
We observed the field of GRB140606B/iPTF14bfu (Singer et al., GCN 16360,
Fermi 432717114, Burns et al. GCN 16363) with the Large Monolithic Imager
(LMI) on the 4.3m Discovery Channel Telescope (DCT) at Happy Jack, AZ from
2014/06/08 9:05 to 2014/06/08 09:41 UTC (starting 29.9 hours after the
Fermi trigger). A source is clearly detected at the location of the
optical afterglow in g', r', i', and z'. Using nearby point sources from
APASS for calibration we obtain the following detections:
g' = 22.8 +/- 0.04
r' = 22.2 +/- 0.04
i' = 22.1 +/- 0.05
z' = 22.1 +/- 0.08
These magnitudes are reported in the AB system and are not corrected for
Galactic extinction in the direction of the GRB. Further observations are
planned.
We thank the staff of the Discovery Channel Telescope for assistance with
these observations.
GCN Circular 16368
Subject
GRB 140606B: Swift/UVOT Upper Limits
Date
2014-06-09T02:46:27Z (11 years ago)
From
Margaret Chester at PSU <chester@swift.psu.edu>
M. M. Chester (PSU) and V. Mangano (PSU) report on behalf of the Swift/UVOT team:
The Swift/UVOT observed the field of the Fermi/GBM-detected burst GRB 140606B beginning 184.4 ks after the Fermi/GBM trigger (Burns et al. GCN Circ. 16363). No source consistent with iPTF14bfu, the optical counterpart proposed by Singer et al. (GCN Circ. 16360) and Perley et al. (GCN Circ. 16365), 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) are given in the following table:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 185271 191914 1693 >21.1
b 186146 192611 1495 >20.9
v 184395 191055 1693 >20.6
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.12 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 16369
Subject
IPN Triangulation of GRB 140606B
Date
2014-06-09T17:03:13Z (11 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,
S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin, and
T. Cline on behalf of the Konus-Wind team, and
V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein,
on behalf of the Fermi GBM team, report:
The long-duration GRB 140606B has been observed by Fermi (Burns GCN
Circ. 16363), Konus-Wind, and MESSENGER (GRNS), so far, at about 11512 s
UT (03:11:52).
We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
---------------------------------------------
RA(2000), deg Dec(2000), deg
---------------------------------------------
Center:
327.109 (21h 48m 26s) +33.047 (+33d 02' 50")
Corners:
321.995 (21h 27m 59s) +37.333 (+37d 19' 58")
321.768 (21h 27m 04s) +38.102 (+38d 06' 06")
332.033 (22h 08m 08s) +27.958 (+27d 57' 29")
332.250 (22h 09m 00s) +26.987 (+26d 59' 14")
---------------------------------------------
The error box area is 5.53 sq. deg, and its maximum
dimension is 14.18 deg (the minimum one is 0.414 deg).
This box may be improved.
Only two of the reported optical sources (Singer et al. GCN Circ.
16360), namely iPTF14bfw and iPTF14bfu, are inside the box, and
iPTF14bfw was found to be a constant source (Perley and Singer, GCN
Circ. 16362).
The distance between the narrowest annulus (GBM-MESSENGER annulus with 3
sigma half width of 0.207 deg) center line and the iPTF14bfu (the fading
source) is 2 arcsec, strengthening the association of the transient
and the GRB.
A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB140606_T11511/IPN/
Details of the Konus-Wind observation will be given in a forthcoming GCN
Circular.
GCN Circular 16373
Subject
GRB 140606B: Swift XRT refined analysis
Date
2014-06-09T21:37:28Z (11 years ago)
From
Vanessa Mangano at PSU <vanessa@ifc.inaf.it>
V. Mangano and D.N. Burrows (PSU)
on behalf of the Swift-XRT team:
Swift XRT performed a second 5 ks ToO observation of the field of
GRB 140606B on June 09 2014, starting about 273.8 ks since the
Fermi/GBM trigger.
The XRT source reported in Mangano et al. (GCN Circ. 16366) is still
detected. The X-ray position, with a 90% error radius of 2.3 arcsec,
is 1.9 arcsec from the optical afterglow candidate iPTF14bfu
proposed by Singer et al. (GCN Circ. 16360).
The XRT light curve shows marginal evidence of decay. Further observations
are planned to confirm it.
This circular is an official product of the Swift-XRT team.
GCN Circular 16374
Subject
Konus-Wind observation of GRB 140606B
Date
2014-06-10T12:20:20Z (11 years ago)
From
Anastasia Tsvetkova at Ioffe Institute <tsvetkova@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik,
M. Ulanov, D. Svinkin, A. Tsvetkova, and T. Cline
on behalf of the Konus-Wind team, report:
The long-duration GRB 140606B (Fermi-GBM detection: Burns, GCN 16319;
IPN triangulation: Golenetskii et al., GCN 16369) triggered Konus-Wind
at T0=11510.769 s UT (03:11:50.769).
The burst light curve shows a single pulse with a duration of ~8 s.
The emission is seen up to ~5 MeV.
As observed by Konus-Wind, the burst had a fluence of
6.6(-0.5,+0.5)x10^-6 erg/cm2, and a 64-ms peak flux, measured from
T0+0.752 s, of 2.9(-0.7,+0.7)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst (measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 5 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.60(-0.18,+0.20),
and Ep = 254(-27,+33) keV (chi2 = 78/73 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.9
(chi2 = 78/72 dof).
Assuming the redshift z=0.384 (Perley et al., GCN 16365)
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 2.5(-0.2,+0.2)x10^51 erg,
the peak luminosity L_iso is 1.5(-0.4,+0.4)x10^51 erg/s,
and the rest-frame peak energy, Ep,i, is 352(-37,+46) keV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB140606_T11510/
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
GCN Circular 16377
Subject
GRB140606B: DCT time of observation correction
Date
2014-06-10T18:35:13Z (11 years ago)
From
Vicki Toy at UMD <vtoy@astro.umd.edu>
V. Toy (UMD), A. Cucchiara (NASA-GSFC), J. Capone (UMD),
D. Kocevski (NASA-GSFC), S.B. Cenko (NASA-GSFC),
E. Troja (NASA-GSFC), A. Kutyrev (NASA-GSFC), S. Veilleux (UMD),
and S. Gezari (UMD) report on behalf of a larger collaboration:
We report that in GCN 16367 we mistakenly estimated the time post-burst
for our DCT observations.
The optical transient was observed from 2014/06/08 9:05 to 2014/06/08
09:41 UTC, which corresponds to 53.9 hours after the GRB discovery
(GCN 16363) and not 29.9 hours as reported.
We apologize for any confusion this might have caused and we thank
Dan Perley for pointing out this inconsistency.
GCN Circular 16387
Subject
GRB 140606B / iPTF 14bfu: MOSFIRE NIR imaging
Date
2014-06-12T02:11:11Z (11 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley (Caltech), M. Kasliwal (Carnegie), L. P. Singer, Y. Cao
(Caltech), and K. Tinyanont (Harvey Mudd) report:
Beginning at 12:57 UT on 2014-06-08 we observed the field of iPTF14bfu
(Singer et al., GCN 16360), the optical counterpart of GRB 140606B
(Burns et al., GCN 16363), using the imaging mode of MOSFIRE on the Keck
I 10m telescope. A sequence of nine 23-second images was acquired in the
Ks filter.
Calibrating relative to 2MASS stars in the image, we measure a magnitude of:
Ks = 19.50 +/- 0.06 (Vega, or Ks = 21.34 AB)
at a mid-time of 2.411 days after the initial trigger.
We also measure an improved astrometric position (relative to 2MASS) of:
21:52:29.961 +32:00:50.66 (J2000, +/- 0.2")
GCN Circular 16398
Subject
GRB 140606B / iPTF 14bfu: AAO optical observations
Date
2014-06-14T14:21:20Z (11 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), R. Inasaridze (AAO), O. Kvaratskhelia (AAO), V.
Ayvazian (AAO), Yu. Krugly (IA KhNU), I. Molotov (KIAM), A. Pozanenko
(IKI) report on behalf of larger GRB follow-up collaboration:
We observed a field of the GBM GRB 140606B / iPTF 14bfu (Singer et al.,
GCN 16360) with AS-32 (0.7m) telescope of Abastumani Observatory
starting on June, 07 (UT) 21:40:06. We obtained several unfiltered
frames with exposure of each frame of 120 s. The optical transient is
well detected on the stacked image.
A photometry is based on nearby USNO-B1.0 stars:
date UT start t-T0 Filter Exp. OT err
(mid, days) (s)
2014-06-07 21:40:06 1.82039 None 46*120 21.95 +/- 0.20
GCN Circular 16403
Subject
GRB 140606B / iPTF 14bfu: Mondy optical observations
Date
2014-06-14T16:46:44Z (11 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), E. Klunko (ISTP), M. Eselevich (ISTP), I. Korobtsev
(ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up
collaboration:
We observed a field of the GBM GRB 140606B / iPTF 14bfu (Singer et al.,
GCN 16360) with with AZT-33IK telescope of Sayan observatory (Mondy). We
obtained several images on June, 08 (UT) 17:17:29 with exposure of each
frame of 120 s. The optical transient Singer et al., GCN 16360) is well
detected on the stacked image. A photometry is based on nearby USNO-B1.0
stars:
date UT start t-T0 Filter Exp. OT
(mid, days) (s)
2014-06-08 17:17:29 2.62892 R 60*120 22.00+/-0.12
The finding chart can be found in
http://grb.rssi.ru/GRB140606B/grb140606B_AZT33IK_R_fc.png
The light curve based on published photometry in r, R and unfiltered
observations (GCNs 16360, 16362, 16367, 16398) can be found in
http://grb.rssi.ru/GRB140606B/grb140606B_lc.png
Based on the lc above one can suggest that a host galaxy of GRB 140606B
may influence on the photometry of the afterglow.
GCN Circular 16412
Subject
GRB 140606B: Swift XRT final light curve
Date
2014-06-16T16:41:48Z (11 years ago)
From
Vanessa Mangano at PSU <vxm22@psu.edu>
V. Mangano (PSU)
on behalf of the Swift-XRT team:
Swift XRT observed the field of GRB 140606B twice after
its return to normal operations for a total of 9 ks exposure.
We confirm that the light curve of the X-ray source given
in Mangano et al. (GCN Circ. 16366 and 16373) shows a
power-law decay with slope 1.0 (+0.7,-0.6).
This circular is an official product of the Swift-XRT team.
GCN Circular 16431
Subject
GRB 140606B / iPTF 14bfu: SAO RAS optical observations
Date
2014-06-21T19:30:55Z (11 years ago)
From
Vladimir Sokolov at SAO RAS <sokolov@sao.ru>
A.S. Moskvitin, V.N. Komarova, V.V. Sokolov, T.N. Sokolova (SAO RAS),
A.F. Valeev (SAO RAS, Kazan Federal Uni.) report on behalf of a larger
GRB follow-up collaboration:
We observed the GRB 140606B / iPTF 14bfu field (Singer et al.,
GCNC 16360) with the 1-m Zeiss-1000 telescope of SAO RAS on June 19/20,
21:26:29 - 00:22:32 UT (13.8 days since the Fermi/GBM trigger).
25 images in Rc band with the total exposure 7500 seconds were obtained.
Near the GRB OT location we clearly detect an object with the brightness
R = 22.1 +/- 0.2, measured against nearby USNO-B1 stars.
This magnitude agrees with the value measured by Volnova et al.
on June 8 (GCNC 16403). Such stability supports an idea that it may be
the host galaxy of GRB 140606B (Perley et al., GCNC 16365).
GCN Circular 16454
Subject
GRB140606B/iPTF14bfu: Keck detection of an associated supernova
Date
2014-06-25T05:24:36Z (11 years ago)
From
Daniel Perley at Caltech <dperley@astro.caltech.edu>
D. A. Perley (Caltech), M. L. Graham, A. V. Filippenko (UC Berkeley),
and S. B. Cenko (GSFC) report:
We acquired a single 1200-second spectrum of iPTF14bfu (Singer et al.,
GCN 16360; Perley et al., GCN 16365), the optical transient associated
with GRB 140606B (Burns et al., GCN 16363), using the Low Resolution
Imaging Spectrometer (LRIS) on the Keck I 10-meter telescope. The
observation was conducted starting at 13:00 UT on 2014-06-24, 18.4 days
after the GBM trigger, and covers a wavelength range from 320-1028
nanometers.
The spectrum shows several broad emission features and a significant
decrease in flux toward both the blue and red ends. A comparison with
SN 1998bw* using superfit (Howell et al. 2005, ApJ 634, 1190) shows a
good match between the observed features and the spectrum of SN 1998bw
near maximum light, indicating that the transient has evolved into a
Type Ic-BL supernova.
* http://www.astro.caltech.edu/~dperley/grb/140606b/140606b_98bw.png