GRB180325_015303_SWIFT at TAROT Calern observatory

TAROT Calern observatory log of images

AL_20180325_015434294_000000_00000001     0 star  filter C [   26.1s -    86.1s] expo= 60s elev=37.8deg humid= 63% sunelev=-35.4deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_015517169_000000_00000001     4 stars filter C [   98.9s -   128.9s] expo= 30s elev=37.6deg humid= 63% sunelev=-35.2deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_015558154_000000_00000001     3 stars filter C [  139.9s -   169.9s] expo= 30s elev=37.5deg humid= 63% sunelev=-35.1deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_015638888_000000_00000001     3 stars filter C [  180.7s -   210.7s] expo= 30s elev=37.3deg humid= 63% sunelev=-35.1deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_015719857_000000_00000001     3 stars filter C [  221.6s -   251.6s] expo= 30s elev=37.2deg humid= 77% sunelev=-35.0deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_015800341_000000_00000001     3 stars filter C [  262.2s -   292.2s] expo= 30s elev=37.1deg humid= 63% sunelev=-34.9deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_015940922_000000_00000001     4 stars filter C [  302.7s -   392.7s] expo= 90s elev=36.9deg humid= 63% sunelev=-34.8deg (moon at  53.0deg phase=0.53 elev= -5.0 )
AL_20180325_020047219_000000_00000001     0 star  filter C [  403.7s -   493.7s] expo= 90s elev=36.6deg humid= 63% sunelev=-34.6deg (moon at  53.0deg phase=0.53 elev= -6.0 )
AL_20180325_020659829_000001_14689201     4 stars filter C [  741.6s -   831.6s] expo= 90s elev=35.5deg humid= 64% sunelev=-33.9deg (moon at  53.0deg phase=0.53 elev= -6.0 )
AL_20180325_020840425_000001_14689201     3 stars filter C [  842.1s -   932.1s] expo= 90s elev=35.2deg humid= 64% sunelev=-33.6deg (moon at  53.0deg phase=0.53 elev= -7.0 )
AL_20180325_021021347_000001_14689201     4 stars filter C [  943.1s -  1033.1s] expo= 90s elev=34.9deg humid= 64% sunelev=-33.4deg (moon at  53.0deg phase=0.53 elev= -7.0 )
AL_20180325_021219675_000003_78820801     3 stars filter C [ 1061.5s -  1151.5s] expo= 90s elev=34.6deg humid= 64% sunelev=-33.1deg (moon at  53.0deg phase=0.53 elev= -7.0 )
AL_20180325_021400643_000003_78820801     3 stars filter C [ 1162.5s -  1252.5s] expo= 90s elev=34.3deg humid= 64% sunelev=-32.9deg (moon at  53.0deg phase=0.53 elev= -7.0 )
AL_20180325_021541628_000003_78820801     3 stars filter C [ 1263.5s -  1353.5s] expo= 90s elev=34.0deg humid= 64% sunelev=-32.7deg (moon at  53.0deg phase=0.53 elev= -8.0 )
AL_20180325_021738143_000003_78820901     3 stars filter C [ 1380.0s -  1470.0s] expo= 90s elev=33.6deg humid= 64% sunelev=-32.4deg (moon at  53.0deg phase=0.53 elev= -8.0 )
AL_20180325_021918398_000003_78820901     4 stars filter C [ 1480.3s -  1570.3s] expo= 90s elev=33.3deg humid= 64% sunelev=-32.2deg (moon at  53.0deg phase=0.53 elev= -8.0 )
AL_20180325_022058507_000003_78820901     3 stars filter C [ 1580.3s -  1670.3s] expo= 90s elev=33.0deg humid= 64% sunelev=-32.0deg (moon at  53.0deg phase=0.53 elev= -8.0 )
AL_20180325_022510914_000003_78821001     4 stars filter C [ 1742.8s -  1922.8s] expo=180s elev=32.4deg humid= 64% sunelev=-31.6deg (moon at  53.0deg phase=0.53 elev= -9.0 )
AL_20180325_022821711_000003_78821001     4 stars filter C [ 1933.5s -  2113.5s] expo=180s elev=31.8deg humid= 64% sunelev=-31.1deg (moon at  53.0deg phase=0.53 elev= -9.0 )
AL_20180325_023132384_000003_78821001     5 stars filter C [ 2124.3s -  2304.3s] expo=180s elev=31.3deg humid= 64% sunelev=-30.7deg (moon at  52.0deg phase=0.53 elev=-10.0 )
AL_20180325_024443277_000001_14689701     3 stars filter C [ 2915.2s -  3095.2s] expo=180s elev=28.9deg humid= 63% sunelev=-28.8deg (moon at  52.0deg phase=0.53 elev=-11.0 )
AL_20180325_024753355_000001_14689701     5 stars filter C [ 3105.3s -  3285.3s] expo=180s elev=28.3deg humid= 63% sunelev=-28.3deg (moon at  52.0deg phase=0.53 elev=-12.0 )
AL_20180325_025103659_000001_14689701     4 stars filter C [ 3295.6s -  3475.6s] expo=180s elev=27.7deg humid= 62% sunelev=-27.8deg (moon at  52.0deg phase=0.53 elev=-12.0 )
AL_20180325_030410635_000001_14689901     4 stars filter C [ 4082.5s -  4262.5s] expo=180s elev=25.4deg humid= 62% sunelev=-25.8deg (moon at  52.0deg phase=0.53 elev=-14.0 )
AL_20180325_030721166_000001_14689901     4 stars filter C [ 4273.1s -  4453.1s] expo=180s elev=24.8deg humid= 62% sunelev=-25.3deg (moon at  52.0deg phase=0.53 elev=-14.0 )
AL_20180325_031031186_000001_14689901     4 stars filter C [ 4463.1s -  4643.1s] expo=180s elev=24.3deg humid= 62% sunelev=-24.8deg (moon at  52.0deg phase=0.53 elev=-15.0 )
AL_20180325_031359592_000003_78821501     3 stars filter C [ 4671.5s -  4851.5s] expo=180s elev=23.7deg humid= 62% sunelev=-24.3deg (moon at  52.0deg phase=0.53 elev=-15.0 )
AL_20180325_031710326_000003_78821501     4 stars filter C [ 4862.2s -  5042.2s] expo=180s elev=23.1deg humid= 62% sunelev=-23.8deg (moon at  52.0deg phase=0.53 elev=-15.0 )
AL_20180325_032020825_000003_78821501     4 stars filter C [ 5052.8s -  5232.8s] expo=180s elev=22.5deg humid= 62% sunelev=-23.2deg (moon at  52.0deg phase=0.53 elev=-16.0 )
AL_20180325_032347294_000001_14690101     4 stars filter C [ 5259.3s -  5439.3s] expo=180s elev=21.9deg humid= 62% sunelev=-22.7deg (moon at  52.0deg phase=0.53 elev=-16.0 )
AL_20180325_032657622_000001_14690101     5 stars filter C [ 5449.6s -  5629.6s] expo=180s elev=21.4deg humid= 61% sunelev=-22.2deg (moon at  52.0deg phase=0.53 elev=-16.0 )
AL_20180325_033007967_000001_14690101     4 stars filter C [ 5639.8s -  5819.8s] expo=180s elev=20.8deg humid= 62% sunelev=-21.7deg (moon at  52.0deg phase=0.53 elev=-17.0 )
AL_20180325_033335327_000001_14690201     6 stars filter C [ 5847.3s -  6027.3s] expo=180s elev=20.2deg humid= 61% sunelev=-21.1deg (moon at  52.0deg phase=0.53 elev=-17.0 )
AL_20180325_033645623_000001_14690201     4 stars filter C [ 6037.6s -  6217.6s] expo=180s elev=19.7deg humid= 61% sunelev=-20.6deg (moon at  52.0deg phase=0.53 elev=-18.0 )
AL_20180325_033955733_000001_14690201     3 stars filter C [ 6227.6s -  6407.6s] expo=180s elev=19.1deg humid= 60% sunelev=-20.0deg (moon at  52.0deg phase=0.53 elev=-18.0 )
AL_20180325_035257832_000001_14690401     3 stars filter C [ 7009.8s -  7189.8s] expo=180s elev=16.9deg humid= 64% sunelev=-17.9deg (moon at  52.0deg phase=0.54 elev=-19.0 )
AL_20180325_035608613_000001_14690401     3 stars filter C [ 7200.5s -  7380.5s] expo=180s elev=16.3deg humid= 64% sunelev=-17.3deg (moon at  52.0deg phase=0.54 elev=-19.0 )
AL_20180325_035919113_000001_14690401     4 stars filter C [ 7391.0s -  7571.0s] expo=180s elev=15.8deg humid= 64% sunelev=-16.8deg (moon at  51.0deg phase=0.54 elev=-20.0 )
AL_20180325_040244964_000001_14690501     4 stars filter C [ 7596.8s -  7776.8s] expo=180s elev=15.2deg humid= 64% sunelev=-16.2deg (moon at  51.0deg phase=0.54 elev=-20.0 )
AL_20180325_040555167_000001_14690501     4 stars filter C [ 7787.1s -  7967.1s] expo=180s elev=14.6deg humid= 62% sunelev=-15.6deg (moon at  51.0deg phase=0.54 elev=-20.0 )
AL_20180325_040905276_000001_14690501     4 stars filter C [ 7977.2s -  8157.2s] expo=180s elev=14.1deg humid= 62% sunelev=-15.1deg (moon at  51.0deg phase=0.54 elev=-21.0 )
AL_20180325_042205793_000001_14690701     3 stars filter C [ 8757.7s -  8937.7s] expo=180s elev=11.9deg humid= 63% sunelev=-12.8deg (moon at  51.0deg phase=0.54 elev=-22.0 )
AL_20180325_042515840_000001_14690701     3 stars filter C [ 8947.7s -  9127.7s] expo=180s elev=11.4deg humid= 63% sunelev=-12.3deg (moon at  51.0deg phase=0.54 elev=-22.0 )
AL_20180325_042826090_000001_14690701     2 stars filter C [ 9138.0s -  9318.0s] expo=180s elev=10.9deg humid= 63% sunelev=-11.7deg (moon at  51.0deg phase=0.54 elev=-22.0 )
AL_20180325_043152617_000001_14690801     2 stars filter C [ 9344.5s -  9524.5s] expo=180s elev=10.3deg humid= 64% sunelev=-11.1deg (moon at  51.0deg phase=0.54 elev=-22.0 )
AL_20180325_043503398_000001_14690801     0 star  filter C [ 9535.3s -  9715.3s] expo=180s elev= 9.8deg humid= 64% sunelev=-10.6deg (moon at  51.0deg phase=0.54 elev=-23.0 )
AL_20180325_043813914_000001_14690801     0 star  filter C [ 9725.8s -  9905.8s] expo=180s elev= 9.3deg humid= 64% sunelev=-10.0deg (moon at  51.0deg phase=0.54 elev=-23.0 )
Informations from GCN notice:
This is a GRB
Date of the alert : 2458202.57850509 2018-03-25T01:53:02.840
Decoded useful notice informations.
RA(J2000.0) : 157.4274 10h29m42s5
DEC(J2000.0) : 24.4634 +24d27m48s23
Error radius : 0.7 arcsec
Error box : x=68:69 y=90:91 (pixels)

Other pages about TAROT Calern observatory observations

Sum of images.
Differential photometry.

Galactic coordinates

Galactic coordinates : lon=209.684244687 lat=58.0902535243
NASA/IPAC-Extragalactic-Database tool for calculate an extinction

Extinction from Schlegel et al. (1998, ApJ 500, 525): E(B-V)=0.017
Assuming Rv=3.1: Av=0.058 Ar=0.046 Ai=0.034
extmap.fit: Extinction map E(B-V) from Schlegel:

Field of View is about 142 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 180325: 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 180325 detected by SWIFT
(trigger 817564) with the TAROT robotic telescope (D=25cm)
located at the Calern observatory, France.

The observations started 26.1s after the GRB trigger
(13.9s after the notice). The elevation of the field decreased from
37 degrees above horizon and weather conditions
were XXX.

---- NO
The date of trigger : t0 = 2018-03-25T01:53:02.840

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+26.1s to t0+86.1s : R > 15.1

The second image is 30.0s exposure in tracking mode:
t0+98.9s to t0+128.9s : R > 16.2

We co-added a series of exposures:
t0+98.9s to t0+392.7s : 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 26.1s 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=209.6842 lat=+58.0903
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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