TITLE:   GCN CIRCULAR
NUMBER:  20497
SUBJECT: LIGO/Virgo G270580: Two optical counterpart candidates from CNEOST
DATE:    17/01/22 13:36:14 GMT
FROM:    Jinzhong Liu at Xinjiang Astronomical Observatory  <liujinzh@xao.ac.cn>

Haibin Zhao (PMO/CAS), Dong Xu (NAO/CAS), Bin Li, Getu Zhaori, Hao Lu
(PMO/CAS), Hanjie Tan(CCU), Zhijian Xu, Wenxiong Li, Zesheng Yang,
Xiaofeng Wang(THU), Lifan Wang (PMO/CAS), Jujia Zhang(YNAO/CAS), Hao
Song (THU), Jinzhong Liu, Hubiao Niu, Yu Zhang, Xuan Zhang, Guangxin Pu,
Shuguo Ma, Taozhi Yang, Fangfang Song (XAO/CAS), Tianmeng Zhang, Xu Zhou
(NAO/CAS), Jirong Mao, Jinming Bai (YNAO/CAS), Huanxue Feng, Zipei
Zhu(NAO/CAS) report on behalf of the Gravitational Wave Follow-Up
Network by NAO-PMO-XAO-YNAO in China (GWFUNC):

We have performed tiled observations of LIGO/Virgo G270580 (LVC, GCN
20486) using the Nanshan One-meter Wide field Telescope (NOWT) in
Xinjiang, the 0.6/0.9-m Schmidt telescope at Xinglong, Hebei, and the
1-m Chinese Near Earth Object Survey Telescope (CNEOST) at Xuyi, Jiangsu.

CNEOST has a FOV of 3.0x3.0 deg^2, and covered more than 1200 square
degree from 10:19:45 UT to 21:46:16 UT on 2017-01-21 in the Sloan
r-filter. The coverage skymap is at

https://dl.dropboxusercontent.com/u/3665676/G270580/skymap20170121NEOST.jpg

The limit magnitude for this survey is of m(r)~21. Each field was
visited three times. Our vetting procedure gives rise to two GW optical
counterpart candidates, potentially supernovae:

Source 1 (dubbed as PTSS-17dfc):
RA (J2000) =10h26m42.37s
Dec(J2000) =+36:40:50.62

with m(r)=16.55 ¡À0.01 mag, and

Source 2 (dubbed as PTSS-17dfn)
RA(J2000) =09h59m44.71s
Dec(J2000)= +27:38:55.44

with m(r)=18.93 ¡À0.08 mag.

The NOWT has a FOV of 1.3 x 1.3 deg^2, and carried out observations in
the nights of 2017-01-20 and 2017-01-21. The liming magnitude is of
m(r)~19. The above two candidates are not covered by NOWT's surveys.

The Schmidt telescope has a FOV of 1.5x1.5 deg^2, and carried out
observations in the night of 2017-01-21. The liming magnitude is of
m(White)~19. The above two candidates are not covered by Schmidt's survey.





--
N: Jinzhong Liu, Dr.
O: Main building, 213
P: 150, Science 1-Street, Urumqi, Xinjiang 830011, China
T: 86 991 3689027
D: 2012-07-14
E: optics@xao.ac.cn