GRB150621_213014_INTEGRAL at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20150621_213138190_000000_00000001     0 star  filter C [   18.7s -    78.7s] expo= 60s elev=38.5deg humid= 87% sunelev=-17.2deg (moon at 131.0deg phase=0.34 elev= +7.0 )
AL_20150621_213223159_000000_00000001    32 stars filter C [   93.6s -   123.6s] expo= 30s elev=38.7deg humid= 87% sunelev=-17.3deg (moon at 131.0deg phase=0.34 elev= +7.0 )
AL_20150621_213303424_000000_00000001    30 stars filter C [  133.9s -   163.9s] expo= 30s elev=38.8deg humid= 87% sunelev=-17.3deg (moon at 131.0deg phase=0.34 elev= +7.0 )
AL_20150621_213344206_000000_00000001    31 stars filter C [  174.7s -   204.7s] expo= 30s elev=38.9deg humid= 87% sunelev=-17.4deg (moon at 131.0deg phase=0.34 elev= +6.0 )
AL_20150621_213424721_000000_00000001    34 stars filter C [  215.2s -   245.2s] expo= 30s elev=39.1deg humid= 87% sunelev=-17.5deg (moon at 131.0deg phase=0.34 elev= +6.0 )
AL_20150621_213505471_000000_00000001    33 stars filter C [  255.9s -   285.9s] expo= 30s elev=39.2deg humid= 87% sunelev=-17.5deg (moon at 131.0deg phase=0.34 elev= +6.0 )
AL_20150621_213646221_000000_00000001    44 stars filter C [  296.7s -   386.7s] expo= 90s elev=39.4deg humid= 87% sunelev=-17.6deg (moon at 131.0deg phase=0.34 elev= +6.0 )
AL_20150621_213827346_000000_00000001    52 stars filter C [  397.9s -   487.9s] expo= 90s elev=39.7deg humid= 88% sunelev=-17.7deg (moon at 131.0deg phase=0.34 elev= +6.0 )
AL_20150621_214008021_000000_00000001    42 stars filter R [  498.4s -   588.4s] expo= 90s elev=40.0deg humid= 88% sunelev=-17.9deg (moon at 131.0deg phase=0.34 elev= +5.0 )
AL_20150621_214149443_000000_00000001    57 stars filter C [  599.9s -   689.9s] expo= 90s elev=40.3deg humid= 88% sunelev=-18.0deg (moon at 131.0deg phase=0.34 elev= +5.0 )
AL_20150621_214329959_000000_00000001    52 stars filter C [  700.4s -   790.4s] expo= 90s elev=40.6deg humid= 88% sunelev=-18.1deg (moon at 131.0deg phase=0.34 elev= +5.0 )
AL_20150621_214511100_000000_00000001    28 stars filter R [  801.6s -   891.6s] expo= 90s elev=40.9deg humid= 89% sunelev=-18.3deg (moon at 131.0deg phase=0.34 elev= +4.0 )
AL_20150621_214651428_000000_00000001    60 stars filter C [  901.9s -   991.9s] expo= 90s elev=41.2deg humid= 89% sunelev=-18.4deg (moon at 131.0deg phase=0.34 elev= +4.0 )
AL_20150621_214704115_000000_00000001     0 star  filter C [ 1003.3s -  1093.3s] expo= 90s elev=41.5deg humid= 88% sunelev=-18.5deg (moon at 131.0deg phase=0.34 elev= +4.0 )
AL_20150621_232803531_000003_46617601     0 star  filter C [ 6997.0s -  7177.0s] expo=180s elev=59.6deg humid= 90% sunelev=-22.8deg (moon at 131.0deg phase=0.35 elev=-12.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2457195.396 2015-06-21T21:30:14.400
Decoded useful notice informations.
RA(J2000.0) : 306.023525704 20h24m05s6
DEC(J2000.0) : 33.8623554754 +33d51m44s47
Error radius : 2.5 arcmin

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=73.1186680836 lat=-2.09969710266
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.500
Assuming Rv=3.1: Av=1.657 Ar=1.336 Ai=0.970 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 150621: 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 150621 detected by INTEGRAL
(trigger 7095) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 18.7s after the GRB trigger
(14.4s after the notice). The elevation of the field increased from
38 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2015-06-21T21:30:14.400

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+18.7s to t0+78.7s : R > 15.1

The second image is 30.0s exposure in tracking mode:
t0+93.6s to t0+123.6s : R > 16.2

We co-added a series of exposures:
t0+93.6s to t0+386.7s : 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 18.7s 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= 73.1187 lat= -2.0997
and the galactic extinction in R band is 1.3 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.