GRB180512_220147_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20180512_220403062_000000_00000001     0 star  filter C [  142.7s -   202.7s] expo= 60s elev=66.9deg humid= 88% sunelev=-25.1deg (moon at 156.0deg phase=0.19 elev=-43.0 )
AL_20180512_221043593_000003_79796901     0 star  filter C [  550.4s -   640.4s] expo= 90s elev=66.5deg humid= 88% sunelev=-25.6deg (moon at 156.0deg phase=0.19 elev=-42.0 )
AL_20180512_224403359_000001_25213801     0 star  filter C [ 2459.7s -  2639.7s] expo=180s elev=63.7deg humid= 96% sunelev=-27.2deg (moon at 156.0deg phase=0.19 elev=-40.0 )
AL_20180512_230447546_000001_25214001     4 stars filter C [ 3616.3s -  3796.3s] expo=180s elev=61.4deg humid= 80% sunelev=-27.7deg (moon at 156.0deg phase=0.19 elev=-39.0 )
AL_20180512_230757343_000001_25214001     5 stars filter C [ 3806.1s -  3986.1s] expo=180s elev=61.0deg humid= 78% sunelev=-27.8deg (moon at 156.0deg phase=0.19 elev=-38.0 )
AL_20180512_231107375_000001_25214001     4 stars filter C [ 3996.2s -  4176.2s] expo=180s elev=60.6deg humid= 76% sunelev=-27.9deg (moon at 156.0deg phase=0.19 elev=-38.0 )
AL_20180512_232421578_000001_25214201     3 stars filter C [ 4790.3s -  4970.3s] expo=180s elev=58.8deg humid= 71% sunelev=-28.0deg (moon at 156.0deg phase=0.19 elev=-37.0 )
AL_20180512_232731968_000001_25214201     5 stars filter C [ 4980.9s -  5160.9s] expo=180s elev=58.3deg humid= 72% sunelev=-28.0deg (moon at 156.0deg phase=0.18 elev=-36.0 )
AL_20180512_233041890_000001_25214201     8 stars filter C [ 5170.7s -  5350.7s] expo=180s elev=57.9deg humid= 73% sunelev=-28.0deg (moon at 156.0deg phase=0.18 elev=-36.0 )
AL_20180512_233413781_000001_25214301     3 stars filter C [ 5382.5s -  5562.5s] expo=180s elev=57.3deg humid= 71% sunelev=-28.0deg (moon at 156.0deg phase=0.18 elev=-36.0 )
AL_20180512_233723828_000001_25214301     4 stars filter C [ 5572.6s -  5752.6s] expo=180s elev=56.9deg humid= 69% sunelev=-28.0deg (moon at 156.0deg phase=0.18 elev=-35.0 )
AL_20180512_234033609_000001_25214301     4 stars filter C [ 5762.4s -  5942.4s] expo=180s elev=56.4deg humid= 70% sunelev=-28.0deg (moon at 156.0deg phase=0.18 elev=-35.0 )
AL_20180512_235338062_000003_79798101     5 stars filter C [ 6546.8s -  6726.8s] expo=180s elev=54.3deg humid= 68% sunelev=-27.8deg (moon at 156.0deg phase=0.18 elev=-33.0 )
AL_20180512_235647859_000003_79798101     5 stars filter C [ 6736.7s -  6916.7s] expo=180s elev=53.8deg humid= 69% sunelev=-27.7deg (moon at 156.0deg phase=0.18 elev=-33.0 )
AL_20180512_235957687_000003_79798101     5 stars filter C [ 6926.5s -  7106.5s] expo=180s elev=53.3deg humid= 69% sunelev=-27.6deg (moon at 156.0deg phase=0.18 elev=-32.0 )
AL_20180513_000329562_000003_79798201     4 stars filter C [ 7138.4s -  7318.4s] expo=180s elev=52.7deg humid= 68% sunelev=-27.5deg (moon at 156.0deg phase=0.18 elev=-32.0 )
AL_20180513_000639531_000003_79798201     5 stars filter C [ 7328.4s -  7508.4s] expo=180s elev=52.2deg humid= 68% sunelev=-27.4deg (moon at 156.0deg phase=0.18 elev=-32.0 )
AL_20180513_000950140_000003_79798201     5 stars filter C [ 7518.9s -  7698.9s] expo=180s elev=51.7deg humid= 66% sunelev=-27.3deg (moon at 156.0deg phase=0.18 elev=-31.0 )
AL_20180513_003224515_000003_79798501     1 star  filter C [ 8873.4s -  9053.4s] expo=180s elev=47.9deg humid= 70% sunelev=-26.4deg (moon at 155.0deg phase=0.18 elev=-28.0 )
AL_20180513_003534578_000003_79798501     0 star  filter C [ 9063.4s -  9243.4s] expo=180s elev=47.3deg humid= 69% sunelev=-26.2deg (moon at 155.0deg phase=0.18 elev=-28.0 )
AL_20180513_003811843_000003_79798501     0 star  filter C [ 9253.5s -  9433.5s] expo=180s elev=46.8deg humid= 66% sunelev=-26.0deg (moon at 155.0deg phase=0.18 elev=-27.0 )
AL_20180513_003913437_000003_79798601     0 star  filter C [ 9455.6s -  9635.6s] expo=180s elev=46.2deg humid= 65% sunelev=-25.8deg (moon at 155.0deg phase=0.18 elev=-27.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2458251.41790579 2018-05-12T22:01:47.060
Decoded useful notice informations.
RA(J2000.0) : 201.9533 13h27m48s7
DEC(J2000.0) : 21.4063 +21d24m22s67
Error radius : 3.0 arcmin

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=0.259292251314 lat=79.9328051254
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.021
Assuming Rv=3.1: Av=0.070 Ar=0.056 Ai=0.041 Extinction map E(B-V) from Schlegel:

Field of View is about 446 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 180512: 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 180512 detected by SWIFT
(trigger 832119) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 142.7s after the GRB trigger
(11.7s after the notice). The elevation of the field decreased from
66 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2018-05-12T22:01:47.060

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+142.7s to t0+202.7s : R > 15.1

The second image is 90.0s exposure in tracking mode:
t0+550.4s to t0+640.4s : R > 16.2

We co-added a series of exposures:
t0+550.4s to t0+4970.3s : 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 142.7s 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=  0.2593 lat=+79.9328
and the galactic extinction in R band is 0.1 magnitudes
estimated from D. Schlegel et al. 1998ApJ...500..525S.

This message may be cited.