GRB150911_184022_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20150912_002826095_000003_51174301     9 stars filter C [20699.2s - 20879.2s] expo=180s elev=23.2deg humid= 94% sunelev=-40.1deg (moon at  88.0deg phase=0.07 elev=-33.0 )
AL_20150912_003136626_000003_51174301     9 stars filter R [20889.7s - 21069.7s] expo=180s elev=23.7deg humid= 94% sunelev=-39.9deg (moon at  88.0deg phase=0.07 elev=-33.0 )
AL_20150912_003447814_000003_51174301     9 stars filter V [21081.0s - 21261.0s] expo=180s elev=24.3deg humid= 94% sunelev=-39.7deg (moon at  88.0deg phase=0.07 elev=-32.0 )
AL_20150912_005305854_000003_51174401    10 stars filter C [22179.0s - 22359.0s] expo=180s elev=27.4deg humid= 94% sunelev=-38.4deg (moon at  88.0deg phase=0.07 elev=-30.0 )
AL_20150912_005617291_000003_51174401     9 stars filter R [22370.5s - 22550.5s] expo=180s elev=27.9deg humid= 93% sunelev=-38.1deg (moon at  88.0deg phase=0.07 elev=-30.0 )
AL_20150912_005928283_000003_51174401     9 stars filter V [22561.4s - 22741.4s] expo=180s elev=28.5deg humid= 93% sunelev=-37.9deg (moon at  88.0deg phase=0.07 elev=-30.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2457277.27803 2015-09-11T18:40:21.792
Decoded useful notice informations.
RA(J2000.0) : 67.4331 04h29m43s9
DEC(J2000.0) : 5.7354 +05d44m07s44
Error radius : 2.2 arcsec
Error box : x=53:54 y=55:56 (pixels)

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=189.455417746 lat=-27.8906235742
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.054
Assuming Rv=3.1: Av=0.178 Ar=0.143 Ai=0.104
extmap.fit: Extinction map E(B-V) from Schlegel:

Field of View is about 75 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
GRBlog
ROTSE last GRB images

Example of a GCNC email for this burst

gcncirc@capella.gsfc.nasa.gov
GRB 150911: 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 150911 detected by SWIFT
(trigger 655262) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 5.75h after the GRB trigger.
The elevation of the field increased from
23 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2015-09-11T18:40:21.792

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+20699.2s to t0+20879.2s : R > 15.1

The second image is 180.0s exposure in tracking mode:
t0+20889.7s to t0+21069.7s : R > 16.2

We co-added a series of exposures:
t0+20889.7s to t0+22741.4s : R > 17.7
---- YES
We detect a new fading source in the error box given by SWIFT
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 5.75h 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=189.4554 lat=-27.8906
and the galactic extinction in R band is 0.1 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.
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