GRB180715_180705_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20180715_203853000_000001_40583801    10 stars filter C [ 8923.0s -  9103.0s] expo=180s elev=43.4deg humid= 56% sunelev=-12.7deg (moon at  81.0deg phase=0.21 elev= +4.0 )
AL_20180715_204202000_000001_40583801    11 stars filter C [ 9112.5s -  9292.5s] expo=180s elev=43.2deg humid= 56% sunelev=-13.1deg (moon at  81.0deg phase=0.21 elev= +3.0 )
AL_20180715_205545000_000001_40584001    11 stars filter C [ 9935.3s - 10115.3s] expo=180s elev=42.2deg humid= 59% sunelev=-14.7deg (moon at  81.0deg phase=0.21 elev= +1.0 )
AL_20180715_205855000_000001_40584001     8 stars filter C [10125.2s - 10305.2s] expo=180s elev=42.0deg humid= 58% sunelev=-15.0deg (moon at  81.0deg phase=0.21 elev= +0.0 )
AL_20180715_210204000_000001_40584001     7 stars filter C [10314.7s - 10494.7s] expo=180s elev=41.7deg humid= 59% sunelev=-15.4deg (moon at  81.0deg phase=0.21 elev= +0.0 )
AL_20180715_214356000_000001_40584501    13 stars filter C [12825.9s - 13005.9s] expo=180s elev=37.5deg humid= 56% sunelev=-19.5deg (moon at  81.0deg phase=0.22 elev= -6.0 )
AL_20180715_214706000_000001_40584501    10 stars filter C [13016.0s - 13196.0s] expo=180s elev=37.1deg humid= 57% sunelev=-19.8deg (moon at  80.0deg phase=0.22 elev= -7.0 )
AL_20180715_215016000_000001_40584501    11 stars filter C [13206.2s - 13386.2s] expo=180s elev=36.7deg humid= 58% sunelev=-20.1deg (moon at  80.0deg phase=0.22 elev= -7.0 )
AL_20180715_215356000_000001_40584601    10 stars filter C [13426.3s - 13606.3s] expo=180s elev=36.3deg humid= 58% sunelev=-20.4deg (moon at  80.0deg phase=0.22 elev= -8.0 )
AL_20180715_215706000_000001_40584601    11 stars filter C [13616.5s - 13796.5s] expo=180s elev=35.9deg humid= 58% sunelev=-20.6deg (moon at  80.0deg phase=0.22 elev= -8.0 )
AL_20180715_220017000_000001_40584601    10 stars filter C [13806.7s - 13986.7s] expo=180s elev=35.5deg humid= 58% sunelev=-20.9deg (moon at  80.0deg phase=0.22 elev= -9.0 )
AL_20180716_001952000_000001_40585401     8 stars filter C [22182.4s - 22362.4s] expo=180s elev=13.7deg humid= 60% sunelev=-24.2deg (moon at  79.0deg phase=0.23 elev=-27.0 )
AL_20180716_002302000_000001_40585401     8 stars filter C [22372.2s - 22552.2s] expo=180s elev=13.1deg humid= 60% sunelev=-24.1deg (moon at  79.0deg phase=0.23 elev=-28.0 )
AL_20180716_002612000_000001_40585401    10 stars filter C [22562.3s - 22742.3s] expo=180s elev=12.6deg humid= 60% sunelev=-24.0deg (moon at  79.0deg phase=0.23 elev=-28.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2458315.25491898 2018-07-15T18:07:05.000
Decoded useful notice informations.
RA(J2000.0) : 235.0688 15h40m16s5
DEC(J2000.0) : -0.9246 -00d55m28s55
Error radius : 3.0 arcmin

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=5.27328953487 lat=40.6747366441
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.124
Assuming Rv=3.1: Av=0.411 Ar=0.331 Ai=0.241
extmap.fit: Extinction map E(B-V) from Schlegel:

Field of View is about 93 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 180715: TAROT Calern observatory optical observations
----------------------------------------------------------------------
Klotz A., Noysena.K., Atteia J.L. (CNRS-OMP-IRAP),
Boer, M., Eymar, L. (CNRS-ARTEMIS),
Gendre B. (UVI - Etelman Obs.) report:

We imaged the field of GRB 180715 detected by SWIFT
(trigger 848048) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 2.48h after the GRB trigger.
The elevation of the field decreased from
43 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2018-07-15T18:07:05.000

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+8923.0s to t0+9103.0s : R > 15.1

The second image is 180.0s exposure in tracking mode:
t0+9112.5s to t0+9292.5s : R > 16.2

We co-added a series of exposures:
t0+9112.5s to t0+13196.0s : 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 2.48h 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=  5.2733 lat=+40.6747
and the galactic extinction in R band is 0.3 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.
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