[vsnet-grb-info 23246] Non-detection of DESGW-190814a in ZTF forced photometry

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  25345
SUBJECT: Non-detection of DESGW-190814a in ZTF forced photometry
DATE:    19/08/15 17:02:53 GMT
FROM:    Kishalay De at Caltech, GROWTH  <kde at astro.caltech.edu>

K. De (Caltech), M. M. Kasliwal (Caltech), I. Andreoni (Caltech) on
behalf of the ZTF and GROWTH collaborations

We performed forced photometry on ZTF images from 2019-08-15 UT at the
location of DESGW-190814a reported in GCN #25336. The field was
observed 3 times in r-band and 2 times in g-band, and no source was
detected above a 5 sigma threshold at the reported location. The
combined 5 sigma upper limit at the location of the source is g = 21.1
mag and r = 21.7 mag. Based on the i and z-band detections reported in
GCN #25336, these upper limits indicate red colors of r - i > 1.1 mag
and r - z > 1.4 mag.

ZTF and GROWTH are worldwide collaborations comprising Caltech, USA;
IPAC, USA, WIS, Israel; OKC, Sweden; JSI/UMd, USA; U Washington, USA;
DESY, Germany; MOST, Taiwan; UW Milwaukee, USA; LANL USA; Tokyo Tech,
Japan; IIT-B, India; IIA, India; LJMU, TTU, and USyd, Australia. ZTF
acknowledges the generous support of the NSF under AST MSIP Grant No
1440341. GROWTH acknowledges generous support of the NSF under PIRE
Grant No 1545949. Alert distribution service provided by DIRAC at UW
(Patterson et al. 2019). Alert filtering and follow-up co-ordination
is being undertaken by the GROWTH marshal system (Kasliwal et al.
2019). The ZTF forced-photometry service was funded under the
Heising-Simons Foundation grant #12540303 (PI: Graham).