[vsnet-grb-info 22244] LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24343
SUBJECT: LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
DATE:    19/04/29 13:58:10 GMT
FROM:    Tomas Ahumada at U. of Maryland  <tahumada at astro.umd.edu>

Tomas Ahumada (UMD), Michael W. Coughlin (Caltech),  Kai Staats
(Northwestern), Kevin Burdge (Caltech), Richard G. Dekany (Caltech), Dmitry
A. Duev (Caltech), Michael Feeney (Caltech), S. R. Kulkarni (Caltech), Reed
Riddle (Caltech) on behalf of the KPED team and the Global Relay of
Observatories Watching Transients Happen (GROWTH) collaboration.

We used the Kitt Peak EMCCD Demonstrator (KPED) on the Kitt Peak 84-inch
telescope (Coughlin et al 2019b) to obtain 300 s r-band images for ZTF
optical transients listed in Kasliwal et al. (GCN 24191) and Anand et al.
(GCN 24311) starting at 3:56:56.876 UT on 2019-04-28.

The measurements of ZTF19aasckkq are consistent with Malesani et al. (GCN
24319) and Ahumada et al. (GCN 24320). The object ZTF19aasbphu shows a
slight decrease in the r magnitude (r~-0.3) with respect to Anand et al.
(GCN 24311)

We report upper limits for the rest of the transients. Magnitudes are
derived after calibrating against PS1:

 ID            JD RA         DEC magnitude

ZTF19aasckkq 2458602.473900463 248.4131017 13.9101828 g = 20.7 +- 0.2

ZTF19aasckkq 2458601.7544584144 248.4131017 13.9101828 r = 20.2 +- 0.1

ZTF19aasckkq 2458602.474675926 248.4131017 13.9101828 r = 20.1 +- 0.1

ZTF19aasckkq 2458601.7452688077 248.4131017 13.9101828 I = 19.4 +- 0.3

ZTF19aasckkq 2458601.750166088 248.4131017 13.9101828 I = 19.4 +- 0.3

ZTF19aasbphu 2458601.7107427316 245.5831354 21.4081853 r = 19.47 +- 0.2

ZTF19aasejil 2458601.8664184026 261.9458106 1.6537207 r > 20.8

ZTF19aasbamy 2458601.664547176 231.2656676 24.9275799 r > 20.4

ZTF19aascxux 2458601.8588976967 258.2933102 17.2938689 r > 20.3

ZTF19aasfogv 2458601.8632696294 261.8430161 -11.3338523 r > 19.9

ZTF19aarycuy 2458602.4741666666 244.0832363 21.7409257 r > 19.9

More observations for this objects are scheduled.

The KPED team thanks the National Science Foundation, the Caltech Space
Innovation Council, the National Optical Astronomical Observatory and the
Murty family for support in the building and operation of KPED.