GRB130421_554135_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20130421_210525604_000002_77432201     2 stars filter C [38135815.6s - 38135875.6s] expo= 60s elev=49.8deg humid= 90% sunelev=-25.1deg (moon at  80.0deg phase=0.72 elev=+47.0 )
AL_20130421_210606792_000002_77432201     1 star  filter C [38135886.8s - 38135916.8s] expo= 30s elev=49.9deg humid= 90% sunelev=-25.2deg (moon at  80.0deg phase=0.72 elev=+47.0 )
AL_20130421_210648901_000002_77432201     3 stars filter C [38135929.0s - 38135959.0s] expo= 30s elev=50.0deg humid= 90% sunelev=-25.3deg (moon at  80.0deg phase=0.72 elev=+47.0 )
AL_20130421_210729657_000002_77432201     3 stars filter C [38135969.7s - 38135999.7s] expo= 30s elev=50.1deg humid= 90% sunelev=-25.4deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_210810923_000002_77432201     3 stars filter C [38136010.9s - 38136040.9s] expo= 30s elev=50.2deg humid= 90% sunelev=-25.4deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_210852079_000002_77432201     0 star  filter C [38136052.1s - 38136082.1s] expo= 30s elev=50.3deg humid= 90% sunelev=-25.5deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_211048360_000002_77432301     0 star  filter C [38136108.4s - 38136198.4s] expo= 90s elev=50.5deg humid= 90% sunelev=-25.6deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_211229126_000002_77432301     0 star  filter C [38136209.2s - 38136299.2s] expo= 90s elev=50.7deg humid= 89% sunelev=-25.8deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_211410141_000002_77432301     3 stars filter C [38136310.1s - 38136400.1s] expo= 90s elev=50.9deg humid= 89% sunelev=-26.0deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_211602423_000002_77432401     0 star  filter C [38136422.5s - 38136512.5s] expo= 90s elev=51.1deg humid= 89% sunelev=-26.2deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_211743181_000002_77432401     0 star  filter C [38136523.2s - 38136613.2s] expo= 90s elev=51.4deg humid= 89% sunelev=-26.4deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_211924415_000002_77432401     0 star  filter C [38136624.4s - 38136714.4s] expo= 90s elev=51.6deg humid= 90% sunelev=-26.6deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_212124618_000002_77432501     3 stars filter C [38136744.7s - 38136834.7s] expo= 90s elev=51.8deg humid= 90% sunelev=-26.8deg (moon at  80.0deg phase=0.72 elev=+46.0 )
AL_20130421_212305118_000002_77432501     3 stars filter C [38136845.2s - 38136935.2s] expo= 90s elev=52.1deg humid= 90% sunelev=-27.0deg (moon at  80.0deg phase=0.72 elev=+45.0 )
AL_20130421_212446352_000002_77432501     4 stars filter C [38136946.4s - 38137036.4s] expo= 90s elev=52.3deg humid= 90% sunelev=-27.1deg (moon at  80.0deg phase=0.72 elev=+45.0 )
AL_20130421_212643321_000002_77432601     4 stars filter C [38137063.4s - 38137153.4s] expo= 90s elev=52.5deg humid= 90% sunelev=-27.3deg (moon at  80.0deg phase=0.72 elev=+45.0 )
AL_20130421_212824295_000002_77432601     5 stars filter C [38137164.4s - 38137254.4s] expo= 90s elev=52.8deg humid= 90% sunelev=-27.5deg (moon at  80.0deg phase=0.72 elev=+45.0 )
AL_20130421_213005295_000002_77432601     4 stars filter C [38137265.3s - 38137355.3s] expo= 90s elev=53.0deg humid= 90% sunelev=-27.7deg (moon at  80.0deg phase=0.72 elev=+45.0 )
AL_20130421_213423295_000002_77432701     5 stars filter C [38137433.4s - 38137613.4s] expo=180s elev=53.4deg humid= 90% sunelev=-28.0deg (moon at  80.0deg phase=0.72 elev=+45.0 )
AL_20130421_213734550_000002_77432701     4 stars filter C [38137624.6s - 38137804.6s] expo=180s elev=53.9deg humid= 91% sunelev=-28.3deg (moon at  80.0deg phase=0.72 elev=+44.0 )
AL_20130421_214046003_000002_77432701     3 stars filter R [38137816.0s - 38137996.0s] expo=180s elev=54.3deg humid= 91% sunelev=-28.6deg (moon at  80.0deg phase=0.72 elev=+44.0 )
AL_20130421_214406238_000002_77432801     3 stars filter C [38138016.3s - 38138196.3s] expo=180s elev=54.7deg humid= 91% sunelev=-28.9deg (moon at  80.0deg phase=0.72 elev=+44.0 )
AL_20130421_214717675_000002_77432801     0 star  filter C [38138207.7s - 38138387.7s] expo=180s elev=55.1deg humid= 91% sunelev=-29.2deg (moon at  80.0deg phase=0.72 elev=+43.0 )
Informations from GCN notice:
This is not a GRB (a retractation has been edited)
Date of GRB : 2455962.9912571758 2012-02-05T11:47:24.619
Date of notice : 2455962.9915046296 2012-02-05T11:47:45.999
Refined position : no
RA(J2000.0) : 40.100000 02h40m24s0
DEC(J2000.0) : 61.220000 +61d13m12s00
Error box : x=-15113:-15003 y=106158:106267 (pixels)

Other pages about TAROT Calern observatory observations

Status of this alert received by TAROT Calern observatory.
Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=91.618517 lat=46.864939
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.015
Assuming Rv=3.1: Av=0.051 Ar=0.041 Ai=0.030 Extinction map E(B-V) from Schlegel:

Field of View is about 106 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 130421: TAROT Calern observatory optical observations
Klotz A. (IRAP-CNRS-OMP), Gendre B. (ASDC/INAF-OAR),
Boer M. (UNS-CNRS-OCA), Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 130421 detected by SWIFT
(trigger 513505) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 38135815.6s after the GRB trigger
(38135794.5s after the notice). The elevation of the field increased from
49 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2012-02-05T11:47:24.864

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+38135815.6s to t0+38135875.6s : R > 15.1

The second image is 30.0s exposure in tracking mode:
t0+38135886.8s to t0+38135916.8s : R > 16.2

We co-added a series of exposures:
t0+38135886.8s to t0+38136198.4s : 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 38135815.6s 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= 91.6185 lat=+46.8649
and the galactic extinction in R band is 0.0 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.