GRB150618_230055_INTEGRAL at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20150618_230216386_000000_00000001     0 star  filter C [   16.2s -    76.2s] expo= 60s elev=52.7deg humid= 77% sunelev=-22.5deg (moon at 129.0deg phase=0.16 elev=-21.0 )
AL_20150618_230301542_000000_00000001    66 stars filter C [   91.4s -   121.4s] expo= 30s elev=52.9deg humid= 77% sunelev=-22.5deg (moon at 129.0deg phase=0.16 elev=-21.0 )
AL_20150618_230341827_000000_00000001    66 stars filter C [  131.7s -   161.7s] expo= 30s elev=53.0deg humid= 77% sunelev=-22.5deg (moon at 129.0deg phase=0.16 elev=-21.0 )
AL_20150618_230422248_000000_00000001    64 stars filter C [  172.2s -   202.2s] expo= 30s elev=53.1deg humid= 77% sunelev=-22.5deg (moon at 129.0deg phase=0.16 elev=-21.0 )
AL_20150618_230503077_000000_00000001    62 stars filter C [  213.0s -   243.0s] expo= 30s elev=53.2deg humid= 77% sunelev=-22.5deg (moon at 129.0deg phase=0.16 elev=-21.0 )
AL_20150618_230543592_000000_00000001    69 stars filter C [  253.5s -   283.5s] expo= 30s elev=53.3deg humid= 77% sunelev=-22.5deg (moon at 129.0deg phase=0.16 elev=-21.0 )
AL_20150618_230724405_000000_00000001    82 stars filter C [  294.2s -   384.2s] expo= 90s elev=53.6deg humid= 77% sunelev=-22.6deg (moon at 129.0deg phase=0.16 elev=-22.0 )
AL_20150618_230904858_000000_00000001    86 stars filter C [  394.7s -   484.7s] expo= 90s elev=53.9deg humid= 77% sunelev=-22.6deg (moon at 129.0deg phase=0.16 elev=-22.0 )
AL_20150618_231046545_000000_00000001    66 stars filter R [  496.4s -   586.4s] expo= 90s elev=54.2deg humid= 76% sunelev=-22.6deg (moon at 129.0deg phase=0.16 elev=-22.0 )
AL_20150618_231131514_000000_00000001     0 star  filter C [  596.9s -   686.9s] expo= 90s elev=54.5deg humid= 76% sunelev=-22.7deg (moon at 129.0deg phase=0.16 elev=-22.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2457192.45897 2015-06-18T23:00:55.008
Decoded useful notice informations.
RA(J2000.0) : 305.999758299 20h23m59s9
DEC(J2000.0) : 33.8850107228 +33d53m06s03
Error radius : 2.6 arcmin
Error box : x=23:119 y=20:115 (pixels)

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=73.127877565 lat=-2.07501931414
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.509
Assuming Rv=3.1: Av=1.688 Ar=1.361 Ai=0.988 Extinction map E(B-V) from Schlegel:

Field of View is about 56 arcmin (north is NOT up !)

Bibliography (Last GCNC circulars and status of satellites)

GCN infos of this burst
GCN notice of this burst
Sloan Digital Sky Survey Observations of Gamma Ray Burst Fields
GCN info bursts
Gamma-ray burst real-time sky map
ROTSE last GRB images

Example of a GCNC email for this burst
GRB 150618: TAROT Calern observatory optical observations
Klotz A., Turpin D. (IRAP-CNRS-OMP),
Boer M., Gendre B., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA),
Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 150618 detected by INTEGRAL
(trigger 7043) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 16.2s after the GRB trigger
(14.5s after the notice). The elevation of the field increased from
52 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2015-06-18T23:00:55.008

The first image is trailed with a duration of 60.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT with a limiting magnitude of:
t0+16.2s to t0+76.2s : R > 15.1

The second image is 30.0s exposure in tracking mode:
t0+91.4s to t0+121.4s : R > 16.2

We co-added a series of exposures:
t0+91.4s to t0+384.2s : R > 17.7
---- YES
We detect a new fading source in the error box given by INTEGRAL
We detected the candidate couterpart mentioned by XXX et al. (GCNC XXXX)
at the following position (+/- 3 arcsec):

RA(J2000.0) = XXh XXm XX.XXs
DEC(J2000.0) +XXd XX' XX.X"

OT was R~XX.X at 16.2s after GRB.

Magnitudes were estimated with the nearby USNO-B1 stars
and are not corrected for galactic dust extinction.

N.B. Galactic coordinates are lon= 73.1279 lat= -2.0750
and the galactic extinction in R band is 1.4 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.