[vsnet-grb-info 22120] LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometry of ZTF19aarykkb and ZTF19aarzaod

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24219
SUBJECT: LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometry of ZTF19aarykkb and ZTF19aarzaod
DATE:    19/04/26 11:27:51 GMT
FROM:    Kumiko Morihana at Nagoya University  <morihana at u.phys.nagoya-u.ac.jp>

K. Morihana (Nagoya Univ.), M. Jian (Univ. of Tokyo), T. Nagayama (Kagoshima Univ.)
report on behalf of J-GEM collaboration:


We observed ZTF19aarykkb and ZTF19aarzaod reported by the Zwicky Transient Facility 
(Kasliwal et al., GCN 24191) with the near-infrared (J, H, Ks) simultaneous imaging camera SIRIUS 
attached to 1.4 m telescope IRSF (InfraRed Survey Facility) in Sutherland observatory, South Africa.

The observation started on 2019-04-26 00:19:13 UT. The exposure times in J-, H-, Ks-bands are
~30min (ZTF19aarykkb) and ~40 min (ZTF19aarzaod), respectively. We performed aperture photometry 
and the magnitude are listed below. The photometric magnitudes may have an effect from the host 
galaxy and nearest stars.

Target                              UTC                   J  (err)        H (err)         Ks (err) 
---------------------------------------------------------------------------------------------------
ZTF19aarykkb   2019-04-26 00:36:51.7   16.8 (0.1)  16.4 (0.1)    16.1 (0.1)  
ZTF19aarzaod   2019-04-26 01:25:52.9   17.4 (0.1)  16.7 (0.1)   16.4 (0.1) 
---------------------------------------------------------------------------------------------------

Given magnitudes were calibrated against 2MASS point sources (Vega System)  in the field.