GRB140818_609885_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20140818_192742221_000003_21670601     0 star  filter C [79947467.4s - 79947647.4s] expo=180s elev=44.6deg humid= 93% sunelev=-9.7deg (moon at 153.0deg phase=0.42 elev=-27.0 )
AL_20140818_203637775_000003_21671301    75 stars filter C [79951567.8s - 79951747.8s] expo=180s elev=43.8deg humid= 92% sunelev=-19.8deg (moon at 154.0deg phase=0.41 elev=-22.0 )
AL_20140818_203949228_000003_21671301    20 stars filter C [79951759.2s - 79951939.2s] expo=180s elev=43.6deg humid= 93% sunelev=-20.2deg (moon at 154.0deg phase=0.41 elev=-21.0 )
AL_20140818_204300150_000003_21671301    10 stars filter R [79951950.2s - 79952130.2s] expo=180s elev=43.4deg humid= 93% sunelev=-20.6deg (moon at 154.0deg phase=0.41 elev=-21.0 )
AL_20140818_204615994_000003_21671401    17 stars filter C [79952146.1s - 79952326.1s] expo=180s elev=43.2deg humid= 92% sunelev=-21.1deg (moon at 154.0deg phase=0.41 elev=-21.0 )
AL_20140818_204926978_000003_21671401    25 stars filter C [79952337.1s - 79952517.1s] expo=180s elev=43.0deg humid= 90% sunelev=-21.5deg (moon at 154.0deg phase=0.41 elev=-20.0 )
AL_20140818_205237953_000003_21671401    33 stars filter R [79952528.0s - 79952708.0s] expo=180s elev=42.8deg humid= 88% sunelev=-21.9deg (moon at 154.0deg phase=0.41 elev=-20.0 )
AL_20140818_205555265_000003_21671501    41 stars filter C [79952725.3s - 79952905.3s] expo=180s elev=42.6deg humid= 87% sunelev=-22.3deg (moon at 154.0deg phase=0.41 elev=-20.0 )
AL_20140818_205906687_000003_21671501    53 stars filter C [79952916.7s - 79953096.7s] expo=180s elev=42.4deg humid= 84% sunelev=-22.7deg (moon at 154.0deg phase=0.41 elev=-19.0 )
AL_20140818_210217640_000003_21671501    31 stars filter R [79953107.7s - 79953287.7s] expo=180s elev=42.1deg humid= 82% sunelev=-23.1deg (moon at 154.0deg phase=0.41 elev=-19.0 )
AL_20140818_210539181_000003_21671601    62 stars filter C [79953309.1s - 79953489.1s] expo=180s elev=41.9deg humid= 81% sunelev=-23.5deg (moon at 154.0deg phase=0.41 elev=-19.0 )
AL_20140818_210849915_000003_21671601    56 stars filter C [79953499.9s - 79953679.9s] expo=180s elev=41.6deg humid= 79% sunelev=-23.8deg (moon at 154.0deg phase=0.41 elev=-18.0 )
AL_20140818_211201384_000003_21671601    15 stars filter R [79953691.3s - 79953871.3s] expo=180s elev=41.4deg humid= 76% sunelev=-24.2deg (moon at 154.0deg phase=0.41 elev=-18.0 )
AL_20140818_211523168_000003_21671701    19 stars filter C [79953893.2s - 79954073.2s] expo=180s elev=41.1deg humid= 74% sunelev=-24.6deg (moon at 154.0deg phase=0.41 elev=-17.0 )
AL_20140818_211833918_000003_21671701     7 stars filter C [79954084.0s - 79954264.0s] expo=180s elev=40.8deg humid= 71% sunelev=-24.9deg (moon at 154.0deg phase=0.41 elev=-17.0 )
AL_20140818_212145153_000003_21671701     0 star  filter R [79954275.2s - 79954455.2s] expo=180s elev=40.5deg humid= 69% sunelev=-25.3deg (moon at 154.0deg phase=0.41 elev=-17.0 )
AL_20140818_212923991_000003_21671901     0 star  filter C [79954734.0s - 79954914.0s] expo=180s elev=39.8deg humid= 67% sunelev=-26.1deg (moon at 154.0deg phase=0.41 elev=-16.0 )
AL_20140818_213234444_000003_21671901     0 star  filter C [79954924.5s - 79955104.5s] expo=180s elev=39.5deg humid= 67% sunelev=-26.4deg (moon at 154.0deg phase=0.41 elev=-15.0 )
AL_20140818_213255944_000003_21671901     0 star  filter R [79955115.5s - 79955295.5s] expo=180s elev=39.1deg humid= 67% sunelev=-26.8deg (moon at 154.0deg phase=0.41 elev=-15.0 )
AL_20140818_215837139_000003_21672201     0 star  filter C [79956487.2s - 79956667.2s] expo=180s elev=36.6deg humid= 64% sunelev=-28.9deg (moon at 154.0deg phase=0.41 elev=-12.0 )
AL_20140818_220148343_000003_21672201     1 star  filter C [79956678.4s - 79956858.4s] expo=180s elev=36.2deg humid= 61% sunelev=-29.2deg (moon at 154.0deg phase=0.41 elev=-12.0 )
AL_20140818_220459581_000003_21672201     8 stars filter R [79956869.6s - 79957049.6s] expo=180s elev=35.8deg humid= 60% sunelev=-29.4deg (moon at 154.0deg phase=0.41 elev=-11.0 )
AL_20140818_220819768_000003_21672301    33 stars filter C [79957069.9s - 79957249.9s] expo=180s elev=35.4deg humid= 58% sunelev=-29.7deg (moon at 154.0deg phase=0.41 elev=-11.0 )
AL_20140818_221130799_000003_21672301    15 stars filter C [79957260.8s - 79957440.8s] expo=180s elev=35.0deg humid= 58% sunelev=-29.9deg (moon at 154.0deg phase=0.41 elev=-10.0 )
AL_20140818_221442021_000003_21672301     3 stars filter R [79957452.1s - 79957632.1s] expo=180s elev=34.6deg humid= 58% sunelev=-30.2deg (moon at 155.0deg phase=0.41 elev=-10.0 )
AL_20140818_221804786_000003_21672401     0 star  filter C [79957654.9s - 79957834.9s] expo=180s elev=34.2deg humid= 59% sunelev=-30.4deg (moon at 155.0deg phase=0.41 elev= -9.0 )
AL_20140818_222115583_000003_21672401     0 star  filter C [79957845.6s - 79958025.6s] expo=180s elev=33.7deg humid= 59% sunelev=-30.6deg (moon at 155.0deg phase=0.41 elev= -9.0 )
AL_20140818_222426335_000003_21672401     0 star  filter R [79958036.4s - 79958216.4s] expo=180s elev=33.3deg humid= 60% sunelev=-30.8deg (moon at 155.0deg phase=0.41 elev= -9.0 )
AL_20140818_222747710_000003_21672501     0 star  filter C [79958237.8s - 79958417.8s] expo=180s elev=32.9deg humid= 61% sunelev=-31.1deg (moon at 155.0deg phase=0.41 elev= -8.0 )
AL_20140818_223058710_000003_21672501     0 star  filter C [79958428.8s - 79958608.8s] expo=180s elev=32.4deg humid= 60% sunelev=-31.2deg (moon at 155.0deg phase=0.41 elev= -8.0 )
AL_20140818_223409679_000003_21672501     0 star  filter R [79958619.7s - 79958799.7s] expo=180s elev=32.0deg humid= 60% sunelev=-31.4deg (moon at 155.0deg phase=0.41 elev= -7.0 )
AL_20140818_223732074_000003_21672601     0 star  filter C [79958822.1s - 79959002.1s] expo=180s elev=31.5deg humid= 60% sunelev=-31.6deg (moon at 155.0deg phase=0.41 elev= -7.0 )
AL_20140818_224042809_000003_21672601     0 star  filter C [79959012.8s - 79959192.8s] expo=180s elev=31.1deg humid= 60% sunelev=-31.8deg (moon at 155.0deg phase=0.41 elev= -6.0 )
AL_20140818_224353559_000003_21672601     0 star  filter R [79959203.6s - 79959383.6s] expo=180s elev=30.6deg humid= 59% sunelev=-32.0deg (moon at 155.0deg phase=0.40 elev= -6.0 )
AL_20140818_224716121_000003_21672701    13 stars filter C [79959406.2s - 79959586.2s] expo=180s elev=30.1deg humid= 59% sunelev=-32.1deg (moon at 155.0deg phase=0.40 elev= -5.0 )
AL_20140818_225026886_000003_21672701     5 stars filter C [79959596.9s - 79959776.9s] expo=180s elev=29.6deg humid= 59% sunelev=-32.3deg (moon at 155.0deg phase=0.40 elev= -5.0 )
AL_20140818_225337621_000003_21672701     0 star  filter R [79959787.7s - 79959967.7s] expo=180s elev=29.2deg humid= 60% sunelev=-32.4deg (moon at 155.0deg phase=0.40 elev= -4.0 )
AL_20140818_225708790_000003_21672801     0 star  filter C [79959998.8s - 79960178.8s] expo=180s elev=28.6deg humid= 62% sunelev=-32.5deg (moon at 155.0deg phase=0.40 elev= -4.0 )
AL_20140818_230019555_000003_21672801     0 star  filter C [79960189.6s - 79960369.6s] expo=180s elev=28.2deg humid= 62% sunelev=-32.6deg (moon at 155.0deg phase=0.40 elev= -3.0 )
AL_20140818_230043055_000003_21672801     0 star  filter R [79960380.6s - 79960560.6s] expo=180s elev=27.7deg humid= 62% sunelev=-32.7deg (moon at 155.0deg phase=0.40 elev= -3.0 )
Informations from GCN notice:
This is not a GRB (a retractation has been edited)
Date of GRB : 2455962.9912571758 2012-02-05T11:47:24.620
Date of notice : 2455962.9915046296 2012-02-05T11:47:46.000
Refined position : no
RA(J2000.0) : 40.1 02h40m24s0
DEC(J2000.0) : 61.22 +61d13m12s00
Error box : x=71518:71627 y=-168339:-168229 (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=26.3081775548 lat=9.77438687052
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.707
Assuming Rv=3.1: Av=2.343 Ar=1.890 Ai=1.371 Extinction map E(B-V) from Schlegel:

Field of View is about 60 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 140818: TAROT Calern observatory optical observations
Klotz A. (IRAP-CNRS-OMP), Gendre B. (IRAP-CNRS-OMP),
Boer M., Siellez K., Dereli H., Bardho O. (UNS-CNRS-OCA),
Atteia J.L. (IRAP-CNRS-OMP) report:

We imaged the field of GRB 140818 detected by SWIFT
(trigger 513505) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 79947467.4s after the GRB trigger
(79947446.3s after the notice). The elevation of the field decreased from
44 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 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+79947467.4s to t0+79947647.4s : R > 15.1

The second image is 180.0s exposure in tracking mode:
t0+79951567.8s to t0+79951747.8s : R > 16.2

We co-added a series of exposures:
t0+79951567.8s to t0+79952708.0s : 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 79947467.4s 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= 26.3082 lat= +9.7744
and the galactic extinction in R band is 1.9 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.