GCN Circular 9142
Subject
GRB090417B: Xinglong TNT optical upper limit
Event
Date
2009-04-18T05:03:56Z (17 years ago)
From
L.P. Xin at NAOC <xlp@bao.ac.cn>
L. P. Xin, X. F. Wang, W. K. Zheng, Y. L. Qiu, J. Y. Wei,
J. Wang, J. S. Deng, Y. Urata and J. Y. Hu
on behalf of EAFON report:
We have observed GRB 090417B (Sbarufatti et al., GCN 9135)
with Xinglong TNT telescope from Apr.17,15:34:38(UT),
14.5 min after the burst. The weather was cloudy.
After combined white and R band images,
no new source was found in our combined images.
The 3 sigma upper limits derived from USNO-B1.0 R2
magnitudes were shown as following:
--------------------------------------------------------
MeanTime exposure Band Mag UpperLimit? coadded?
--------------------------------------------------------
16.5min 8*40s white 20.1 yes yes
1.63hr 29*300s R 21.6 yes yes
-------------------------------------------------------
We also notice that in the location of XRT error circle,
a extended object was likely to be present,
as found by Fynbo et al (GCN 9140).
However, the S/N is very low that we could not make sure.
This message may be cited.
For more information about Xinglong GRBs Follow-up
observations, please visit the website:
http://www.xinglong-naoc.org/grb/