GRB120521_232208_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20120521_234643531_000002_53292001     7 stars filter C [ 1380.9s -  1470.9s] expo= 90s elev=68.8deg humid= 93% sunelev=-25.7deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_234825016_000002_53292001     6 stars filter C [ 1482.3s -  1572.3s] expo= 90s elev=68.5deg humid= 93% sunelev=-25.7deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_235005954_000002_53292001     7 stars filter C [ 1583.3s -  1673.3s] expo= 90s elev=68.2deg humid= 93% sunelev=-25.7deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_235200376_000002_53292101     6 stars filter C [ 1697.7s -  1787.7s] expo= 90s elev=67.9deg humid= 93% sunelev=-25.7deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_235340922_000002_53292101     7 stars filter C [ 1798.2s -  1888.2s] expo= 90s elev=67.6deg humid= 93% sunelev=-25.6deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_235521890_000002_53292101     6 stars filter C [ 1899.2s -  1989.2s] expo= 90s elev=67.3deg humid= 93% sunelev=-25.6deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_235719097_000002_53292201     7 stars filter C [ 2016.4s -  2106.4s] expo= 90s elev=66.9deg humid= 93% sunelev=-25.6deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120521_235900066_000002_53292201     8 stars filter C [ 2117.4s -  2207.4s] expo= 90s elev=66.6deg humid= 92% sunelev=-25.5deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_000040988_000002_53292201     7 stars filter C [ 2218.3s -  2308.3s] expo= 90s elev=66.3deg humid= 92% sunelev=-25.5deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_000455784_000002_53292301     8 stars filter C [ 2383.1s -  2563.1s] expo=180s elev=65.7deg humid= 92% sunelev=-25.4deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_000806768_000002_53292301     8 stars filter C [ 2574.1s -  2754.1s] expo=180s elev=65.1deg humid= 92% sunelev=-25.3deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_001117502_000002_53292301     6 stars filter R [ 2764.8s -  2944.8s] expo=180s elev=64.5deg humid= 92% sunelev=-25.2deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_001436080_000002_53292401     7 stars filter C [ 2963.4s -  3143.4s] expo=180s elev=63.9deg humid= 92% sunelev=-25.1deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_001747064_000002_53292401     8 stars filter C [ 3154.4s -  3334.4s] expo=180s elev=63.4deg humid= 91% sunelev=-25.0deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_002057345_000002_53292401     7 stars filter R [ 3344.7s -  3524.7s] expo=180s elev=62.8deg humid= 91% sunelev=-24.9deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_002428079_000002_53292501    10 stars filter C [ 3555.4s -  3735.4s] expo=180s elev=62.2deg humid= 91% sunelev=-24.7deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_002739017_000002_53292501     8 stars filter C [ 3746.3s -  3926.3s] expo=180s elev=61.6deg humid= 91% sunelev=-24.6deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_003049315_000002_53292501     6 stars filter R [ 3936.6s -  4116.6s] expo=180s elev=61.0deg humid= 91% sunelev=-24.4deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_003416706_000002_53292601     7 stars filter C [ 4144.1s -  4324.1s] expo=180s elev=60.4deg humid= 90% sunelev=-24.3deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_003727916_000002_53292601     7 stars filter C [ 4335.3s -  4515.3s] expo=180s elev=59.9deg humid= 90% sunelev=-24.1deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_004038431_000002_53292601     5 stars filter R [ 4525.8s -  4705.8s] expo=180s elev=59.3deg humid= 91% sunelev=-23.9deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_004405917_000002_53292701     8 stars filter C [ 4733.2s -  4913.2s] expo=180s elev=58.7deg humid= 91% sunelev=-23.7deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_004716884_000002_53292701     8 stars filter C [ 4924.2s -  5104.2s] expo=180s elev=58.1deg humid= 91% sunelev=-23.5deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_005027384_000002_53292701     6 stars filter R [ 5114.7s -  5294.7s] expo=180s elev=57.6deg humid= 92% sunelev=-23.3deg (moon at 108.0deg phase=0.06 elev=-25.0 )
AL_20120522_005355073_000002_53292801     7 stars filter C [ 5322.4s -  5502.4s] expo=180s elev=57.0deg humid= 91% sunelev=-23.1deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_005706030_000002_53292801     5 stars filter C [ 5513.3s -  5693.3s] expo=180s elev=56.4deg humid= 91% sunelev=-22.9deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_010016765_000002_53292801     4 stars filter R [ 5704.1s -  5884.1s] expo=180s elev=55.8deg humid= 91% sunelev=-22.7deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_010344202_000002_53292901     5 stars filter C [ 5911.5s -  6091.5s] expo=180s elev=55.2deg humid= 91% sunelev=-22.4deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_010655411_000002_53292901     4 stars filter C [ 6102.7s -  6282.7s] expo=180s elev=54.7deg humid= 91% sunelev=-22.2deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_011005707_000002_53292901     5 stars filter R [ 6293.0s -  6473.0s] expo=180s elev=54.1deg humid= 90% sunelev=-22.0deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_011333146_000002_53293001     5 stars filter C [ 6500.4s -  6680.4s] expo=180s elev=53.5deg humid= 90% sunelev=-21.7deg (moon at 108.0deg phase=0.06 elev=-24.0 )
AL_20120522_011644113_000002_53293001     6 stars filter C [ 6691.4s -  6871.4s] expo=180s elev=53.0deg humid= 90% sunelev=-21.5deg (moon at 108.0deg phase=0.07 elev=-24.0 )
AL_20120522_011955503_000002_53293001     4 stars filter R [ 6882.8s -  7062.8s] expo=180s elev=52.4deg humid= 89% sunelev=-21.2deg (moon at 108.0deg phase=0.07 elev=-24.0 )
AL_20120522_012323159_000002_53293101     6 stars filter C [ 7090.5s -  7270.5s] expo=180s elev=51.8deg humid= 89% sunelev=-20.9deg (moon at 108.0deg phase=0.07 elev=-23.0 )
AL_20120522_012634363_000002_53293101     5 stars filter C [ 7281.7s -  7461.7s] expo=180s elev=51.3deg humid= 90% sunelev=-20.6deg (moon at 108.0deg phase=0.07 elev=-23.0 )
AL_20120522_012944700_000002_53293101     4 stars filter R [ 7472.0s -  7652.0s] expo=180s elev=50.7deg humid= 90% sunelev=-20.3deg (moon at 108.0deg phase=0.07 elev=-23.0 )
AL_20120522_013311215_000002_53293201     5 stars filter C [ 7678.5s -  7858.5s] expo=180s elev=50.1deg humid= 90% sunelev=-20.0deg (moon at 108.0deg phase=0.07 elev=-23.0 )
AL_20120522_013622419_000002_53293201     4 stars filter C [ 7869.7s -  8049.7s] expo=180s elev=49.6deg humid= 90% sunelev=-19.7deg (moon at 108.0deg phase=0.07 elev=-23.0 )
AL_20120522_013932647_000002_53293201     2 stars filter R [ 8060.0s -  8240.0s] expo=180s elev=49.0deg humid= 90% sunelev=-19.4deg (moon at 108.0deg phase=0.07 elev=-22.0 )
AL_20120522_014300367_000002_53293301     3 stars filter C [ 8267.6s -  8447.6s] expo=180s elev=48.4deg humid= 89% sunelev=-19.1deg (moon at 108.0deg phase=0.07 elev=-22.0 )
AL_20120522_014611335_000002_53293301     4 stars filter C [ 8458.6s -  8638.6s] expo=180s elev=47.9deg humid= 90% sunelev=-18.8deg (moon at 108.0deg phase=0.07 elev=-22.0 )
AL_20120522_014922021_000002_53293301     3 stars filter R [ 8649.4s -  8829.4s] expo=180s elev=47.3deg humid= 89% sunelev=-18.5deg (moon at 108.0deg phase=0.07 elev=-22.0 )
AL_20120522_015249460_000002_53293401     0 star  filter C [ 8856.8s -  9036.8s] expo=180s elev=46.7deg humid= 89% sunelev=-18.1deg (moon at 108.0deg phase=0.07 elev=-22.0 )
AL_20120522_015559741_000002_53293401     0 star  filter C [ 9047.1s -  9227.1s] expo=180s elev=46.2deg humid= 88% sunelev=-17.8deg (moon at 108.0deg phase=0.07 elev=-21.0 )
AL_20120522_015910990_000002_53293401     0 star  filter R [ 9238.3s -  9418.3s] expo=180s elev=45.7deg humid= 88% sunelev=-17.5deg (moon at 108.0deg phase=0.07 elev=-21.0 )
AL_20120522_020246740_000002_53293501     3 stars filter C [ 9454.1s -  9634.1s] expo=180s elev=45.0deg humid= 88% sunelev=-17.1deg (moon at 108.0deg phase=0.07 elev=-21.0 )
AL_20120522_020557068_000002_53293501     4 stars filter C [ 9644.3s -  9824.3s] expo=180s elev=44.5deg humid= 88% sunelev=-16.7deg (moon at 107.0deg phase=0.07 elev=-21.0 )
AL_20120522_020907290_000002_53293501     3 stars filter R [ 9834.6s - 10014.6s] expo=180s elev=44.0deg humid= 89% sunelev=-16.4deg (moon at 107.0deg phase=0.07 elev=-20.0 )
AL_20120522_021224775_000002_53293601     3 stars filter C [10032.1s - 10212.1s] expo=180s elev=43.4deg humid= 89% sunelev=-16.0deg (moon at 107.0deg phase=0.07 elev=-20.0 )
AL_20120522_021535727_000002_53293601     0 star  filter C [10223.1s - 10403.1s] expo=180s elev=42.9deg humid= 89% sunelev=-15.6deg (moon at 107.0deg phase=0.07 elev=-20.0 )
AL_20120522_021846278_000002_53293601     0 star  filter R [10413.6s - 10593.6s] expo=180s elev=42.4deg humid= 88% sunelev=-15.3deg (moon at 107.0deg phase=0.07 elev=-20.0 )
AL_20120522_022212794_000002_53293701     0 star  filter C [10620.1s - 10800.1s] expo=180s elev=41.8deg humid= 88% sunelev=-14.8deg (moon at 107.0deg phase=0.07 elev=-19.0 )
AL_20120522_022524185_000002_53293701     0 star  filter C [10811.5s - 10991.5s] expo=180s elev=41.3deg humid= 89% sunelev=-14.5deg (moon at 107.0deg phase=0.07 elev=-19.0 )
AL_20120522_022835417_000002_53293701     0 star  filter R [11002.7s - 11182.7s] expo=180s elev=40.7deg humid= 89% sunelev=-14.1deg (moon at 107.0deg phase=0.07 elev=-19.0 )
AL_20120522_023630918_000002_53293901     0 star  filter C [11478.2s - 11658.2s] expo=180s elev=39.4deg humid= 89% sunelev=-13.1deg (moon at 107.0deg phase=0.07 elev=-18.0 )
AL_20120522_023941182_000002_53293901     0 star  filter C [11668.5s - 11848.5s] expo=180s elev=38.9deg humid= 89% sunelev=-12.7deg (moon at 107.0deg phase=0.07 elev=-18.0 )
AL_20120522_024251887_000002_53293901     0 star  filter R [11859.2s - 12039.2s] expo=180s elev=38.4deg humid= 89% sunelev=-12.3deg (moon at 107.0deg phase=0.07 elev=-17.0 )
AL_20120522_024621417_000002_53294001     0 star  filter C [12068.8s - 12248.8s] expo=180s elev=37.8deg humid= 89% sunelev=-11.8deg (moon at 107.0deg phase=0.07 elev=-17.0 )
AL_20120522_024932380_000002_53294001     0 star  filter C [12259.7s - 12439.7s] expo=180s elev=37.3deg humid= 89% sunelev=-11.4deg (moon at 107.0deg phase=0.07 elev=-17.0 )
AL_20120522_025242709_000002_53294001     0 star  filter R [12450.0s - 12630.0s] expo=180s elev=36.8deg humid= 89% sunelev=-11.0deg (moon at 107.0deg phase=0.07 elev=-16.0 )
AL_20120522_025618491_000002_53294101     0 star  filter C [12665.8s - 12845.8s] expo=180s elev=36.2deg humid= 89% sunelev=-10.5deg (moon at 107.0deg phase=0.07 elev=-16.0 )
AL_20120522_025929380_000002_53294101     0 star  filter C [12856.8s - 13036.8s] expo=180s elev=35.7deg humid= 88% sunelev=-10.1deg (moon at 107.0deg phase=0.07 elev=-16.0 )
AL_20120522_030239989_000002_53294101     0 star  filter R [13047.3s - 13227.3s] expo=180s elev=35.2deg humid= 89% sunelev=-9.7deg (moon at 107.0deg phase=0.07 elev=-15.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2456069.4737 2012-05-21T23:22:07.679
Decoded useful notice informations.
RA(J2000.0) : 214.286 14h17m08s6
DEC(J2000.0) : 42.1438 +42d08m37s67
Error radius : 5.8 arcsec
Error box : x=65:69 y=85:88 (pixels)

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=79.083082 lat=66.971506
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.009
Assuming Rv=3.1: Av=0.031 Ar=0.025 Ai=0.018
extmap.fit: Extinction map E(B-V) from Schlegel:

Field of View is about 196 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 120521: 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 120521 detected by SWIFT
(trigger 522656) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 23.02min after the GRB trigger
(729.4s after the notice). The elevation of the field decreased from
68 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2012-05-21T23:22:07.679

The first image is trailed with a duration of 90.0s
(see the description in Klotz et al., 2006, A&A 451, L39).
We do not detect any OT with a limiting magnitude of:
t0+1380.9s to t0+1470.9s : R > 15.1

The second image is 90.0s exposure in tracking mode:
t0+1482.3s to t0+1572.3s : R > 16.2

We co-added a series of exposures:
t0+1482.3s to t0+2106.4s : 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 23.02min 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= 79.0831 lat=+66.9715
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.
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