GRB180222_002027_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20180222_022949927_000003_78287401     0 star  filter C [ 7576.9s -  7756.9s] expo=180s elev= 2.4deg humid= 54% sunelev=-41.7deg (moon at 133.0deg phase=0.41 elev=-28.0 )
AL_20180222_023300412_000003_78287401     0 star  filter C [ 7767.5s -  7947.5s] expo=180s elev= 3.0deg humid= 53% sunelev=-41.2deg (moon at 133.0deg phase=0.41 elev=-28.0 )
AL_20180222_023933724_000001_10479901     0 star  filter C [ 8160.8s -  8340.8s] expo=180s elev= 4.0deg humid= 53% sunelev=-40.1deg (moon at 133.0deg phase=0.41 elev=-29.0 )
AL_20180222_024244677_000001_10479901     0 star  filter C [ 8351.8s -  8531.8s] expo=180s elev= 4.6deg humid= 53% sunelev=-39.6deg (moon at 133.0deg phase=0.41 elev=-29.0 )
AL_20180222_024555006_000001_10479901     0 star  filter C [ 8542.1s -  8722.1s] expo=180s elev= 5.1deg humid= 53% sunelev=-39.1deg (moon at 133.0deg phase=0.41 elev=-30.0 )
AL_20180222_025342069_000001_10480101     0 star  filter C [ 9009.2s -  9189.2s] expo=180s elev= 6.4deg humid= 53% sunelev=-37.9deg (moon at 133.0deg phase=0.41 elev=-30.0 )
AL_20180222_025652366_000001_10480101     0 star  filter C [ 9199.5s -  9379.5s] expo=180s elev= 6.9deg humid= 53% sunelev=-37.4deg (moon at 133.0deg phase=0.41 elev=-30.0 )
AL_20180222_030003348_000001_10480101     0 star  filter C [ 9390.4s -  9570.4s] expo=180s elev= 7.5deg humid= 52% sunelev=-36.8deg (moon at 133.0deg phase=0.41 elev=-31.0 )
AL_20180222_030647348_000001_10480201     0 star  filter C [ 9794.4s -  9974.4s] expo=180s elev= 8.6deg humid= 51% sunelev=-35.7deg (moon at 133.0deg phase=0.41 elev=-31.0 )
AL_20180222_030957687_000001_10480201     0 star  filter C [ 9984.7s - 10164.7s] expo=180s elev= 9.1deg humid= 51% sunelev=-35.2deg (moon at 133.0deg phase=0.41 elev=-31.0 )
AL_20180222_031321406_000001_10480301     0 star  filter C [10188.5s - 10368.5s] expo=180s elev= 9.7deg humid= 52% sunelev=-34.6deg (moon at 133.0deg phase=0.41 elev=-32.0 )
AL_20180222_031557469_000001_10480301     0 star  filter C [10379.0s - 10559.0s] expo=180s elev=10.2deg humid= 52% sunelev=-34.1deg (moon at 133.0deg phase=0.41 elev=-32.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2458171.51420694 2018-02-22T00:20:27.480
Decoded useful notice informations.
RA(J2000.0) : 273.387 18h13m32s8
DEC(J2000.0) : -9.5008 -09d30m02s88
Error radius : 3.0 arcmin

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=20.1378749044 lat=3.96772295653
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=1.712
Assuming Rv=3.1: Av=5.674 Ar=4.575 Ai=3.320
extmap.fit: Extinction map E(B-V) from Schlegel:

Field of View is about 57 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 180222: 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 180222 detected by SWIFT
(trigger 811167) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 2.10h after the GRB trigger.
The elevation of the field increased from
2 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2018-02-22T00:20:27.480

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+7576.9s to t0+7756.9s : R > 15.1

The second image is 180.0s exposure in tracking mode:
t0+7767.5s to t0+7947.5s : R > 16.2

We co-added a series of exposures:
t0+7767.5s to t0+9379.5s : 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 2.10h 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= 20.1379 lat= +3.9677
and the galactic extinction in R band is 4.6 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.
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