GRB150618_000831_INTEGRAL at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20150618_000959450_000000_00000001     0 star  filter C [   23.7s -    83.7s] expo= 60s elev=64.2deg humid= 88% sunelev=-22.3deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_001044747_000000_00000001    71 stars filter C [   99.1s -   129.1s] expo= 30s elev=64.3deg humid= 88% sunelev=-22.3deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_001125279_000000_00000001    67 stars filter C [  139.6s -   169.6s] expo= 30s elev=64.5deg humid= 89% sunelev=-22.3deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_001134732_000000_00000001     0 star  filter C [  180.6s -   210.6s] expo= 30s elev=64.6deg humid= 89% sunelev=-22.3deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_001659404_000003_46259701    92 stars filter C [  413.7s -   503.7s] expo= 90s elev=65.4deg humid= 88% sunelev=-22.1deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_001840607_000003_46259701    89 stars filter C [  514.9s -   604.9s] expo= 90s elev=65.7deg humid= 88% sunelev=-22.1deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_002021368_000003_46259701    89 stars filter C [  615.7s -   705.7s] expo= 90s elev=66.0deg humid= 88% sunelev=-22.0deg (moon at 125.0deg phase=0.10 elev=-28.0 )
AL_20150618_002211884_000003_46259801    90 stars filter C [  726.2s -   816.2s] expo= 90s elev=66.3deg humid= 88% sunelev=-22.0deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_002353509_000003_46259801    87 stars filter C [  827.8s -   917.8s] expo= 90s elev=66.6deg humid= 88% sunelev=-21.9deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_002534071_000003_46259801    91 stars filter C [  928.4s -  1018.4s] expo= 90s elev=66.9deg humid= 88% sunelev=-21.8deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_002726634_000003_46259901    96 stars filter C [ 1040.9s -  1130.9s] expo= 90s elev=67.2deg humid= 88% sunelev=-21.8deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_002908337_000003_46259901    98 stars filter C [ 1142.6s -  1232.6s] expo= 90s elev=67.5deg humid= 88% sunelev=-21.7deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_003049241_000003_46259901    88 stars filter C [ 1243.6s -  1333.6s] expo= 90s elev=67.8deg humid= 88% sunelev=-21.6deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_003249256_000003_46260001    92 stars filter C [ 1363.6s -  1453.6s] expo= 90s elev=68.1deg humid= 87% sunelev=-21.5deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_003430006_000003_46260001    96 stars filter C [ 1464.3s -  1554.3s] expo= 90s elev=68.4deg humid= 87% sunelev=-21.4deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_003611256_000003_46260001    94 stars filter C [ 1565.6s -  1655.6s] expo= 90s elev=68.7deg humid= 87% sunelev=-21.4deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_010219986_000003_46260301    92 stars filter C [ 3044.3s -  3224.3s] expo=180s elev=72.9deg humid= 87% sunelev=-20.0deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_010530767_000003_46260301    98 stars filter C [ 3235.0s -  3415.0s] expo=180s elev=73.4deg humid= 87% sunelev=-19.8deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_010738439_000003_46260301     0 star  filter R [ 3426.0s -  3606.0s] expo=180s elev=73.9deg humid= 86% sunelev=-19.5deg (moon at 125.0deg phase=0.10 elev=-29.0 )
AL_20150618_015109644_000003_46260801    88 stars filter C [ 5973.9s -  6153.9s] expo=180s elev=79.2deg humid= 87% sunelev=-16.0deg (moon at 125.0deg phase=0.11 elev=-27.0 )
AL_20150618_015420159_000003_46260801    91 stars filter C [ 6164.4s -  6344.4s] expo=180s elev=79.4deg humid= 87% sunelev=-15.7deg (moon at 125.0deg phase=0.11 elev=-27.0 )
AL_20150618_015731003_000003_46260801    60 stars filter R [ 6355.2s -  6535.2s] expo=180s elev=79.6deg humid= 87% sunelev=-15.4deg (moon at 125.0deg phase=0.11 elev=-27.0 )
AL_20150618_020047644_000003_46260901   106 stars filter C [ 6551.7s -  6731.7s] expo=180s elev=79.8deg humid= 87% sunelev=-15.0deg (moon at 125.0deg phase=0.11 elev=-27.0 )
AL_20150618_020358224_000003_46260901    98 stars filter C [ 6742.5s -  6922.5s] expo=180s elev=80.0deg humid= 86% sunelev=-14.7deg (moon at 125.0deg phase=0.11 elev=-27.0 )
AL_20150618_020710099_000003_46260901    76 stars filter R [ 6934.2s -  7114.2s] expo=180s elev=80.1deg humid= 87% sunelev=-14.4deg (moon at 125.0deg phase=0.11 elev=-26.0 )
AL_20150618_021028506_000003_46261001   103 stars filter C [ 7132.8s -  7312.8s] expo=180s elev=80.1deg humid= 87% sunelev=-14.0deg (moon at 125.0deg phase=0.11 elev=-26.0 )
AL_20150618_021340149_000003_46261001    81 stars filter C [ 7324.5s -  7504.5s] expo=180s elev=80.2deg humid= 87% sunelev=-13.7deg (moon at 125.0deg phase=0.11 elev=-26.0 )
AL_20150618_021650977_000003_46261001    84 stars filter R [ 7515.2s -  7695.2s] expo=180s elev=80.2deg humid= 88% sunelev=-13.3deg (moon at 125.0deg phase=0.11 elev=-26.0 )
AL_20150618_022427393_000003_46261201    95 stars filter C [ 7971.6s -  8151.6s] expo=180s elev=80.0deg humid= 88% sunelev=-12.5deg (moon at 125.0deg phase=0.11 elev=-25.0 )
AL_20150618_022738065_000003_46261201    88 stars filter C [ 8162.3s -  8342.3s] expo=180s elev=79.8deg humid= 88% sunelev=-12.1deg (moon at 125.0deg phase=0.11 elev=-25.0 )
AL_20150618_023048800_000003_46261201    68 stars filter R [ 8353.1s -  8533.1s] expo=180s elev=79.7deg humid= 88% sunelev=-11.8deg (moon at 125.0deg phase=0.11 elev=-25.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2457191.50591 2015-06-18T00:08:30.624
Decoded useful notice informations.
RA(J2000.0) : 305.986155603 20h23m56s6
DEC(J2000.0) : 33.8643358387 +33d51m51s60
Error radius : 3.1 arcmin
Error box : x=12:127 y=-5:109 (pixels)

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=73.1146201288 lat=-2.06605073812
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.521
Assuming Rv=3.1: Av=1.727 Ar=1.392 Ai=1.010 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 7015) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 23.7s after the GRB trigger
(15.9s after the notice). The elevation of the field increased from
64 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2015-06-18T00:08:30.624

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+23.7s to t0+83.7s : R > 15.1

The second image is 30.0s exposure in tracking mode:
t0+99.1s to t0+129.1s : R > 16.2

We co-added a series of exposures:
t0+99.1s to t0+705.7s : 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 23.7s 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= 73.1146 lat= -2.0661
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.