GRB150620_175521_INTEGRAL at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20150620_225541749_000003_46516801     0 star  filter C [17835.8s - 18015.8s] expo=180s elev=52.7deg humid= 79% sunelev=-22.2deg (moon at 133.0deg phase=0.29 elev=-11.0 )
AL_20150620_225734842_000003_46516801     0 star  filter R [18027.0s - 18207.0s] expo=180s elev=53.2deg humid= 79% sunelev=-22.3deg (moon at 133.0deg phase=0.29 elev=-12.0 )
AL_20150620_234705903_000003_46517001     0 star  filter C [20919.9s - 21099.9s] expo=180s elev=61.9deg humid= 76% sunelev=-22.8deg (moon at 133.0deg phase=0.29 elev=-19.0 )
AL_20150620_234926543_000003_46517001     0 star  filter R [21110.4s - 21290.4s] expo=180s elev=62.5deg humid= 76% sunelev=-22.7deg (moon at 133.0deg phase=0.29 elev=-20.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2457194.24677 2015-06-20T17:55:20.928
Decoded useful notice informations.
RA(J2000.0) : 306.048117774 20h24m11s5
DEC(J2000.0) : 33.8487358873 +33d50m55s44
Error radius : 2.6 arcmin
Error box : x=46:143 y=35:132 (pixels)

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=73.1153294582 lat=-2.14770325126
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.508
Assuming Rv=3.1: Av=1.684 Ar=1.358 Ai=0.985 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 150620: 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 150620 detected by INTEGRAL
(trigger 7070) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 4.95h after the GRB trigger.
The elevation of the field increased from
52 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2015-06-20T17:55:20.928

The first image is trailed with a duration of 180.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT with a limiting magnitude of:
t0+17835.8s to t0+18015.8s : R > 15.1

The second image is 180.0s exposure in tracking mode:
t0+18027.0s to t0+18207.0s : R > 16.2

We co-added a series of exposures:
t0+18027.0s to t0+21290.4s : 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 4.95h 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= 73.1153 lat= -2.1477
and the galactic extinction in R band is 1.4 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

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