ZTF discovery of an outburst from the Black Hole X-ray Transient Swift J1357.2-0933
ATel #12796; Sjoert van Velzen (UMd), Eric C. Bellm (UW), and Jan van Roestel (Caltech) on behalf of the Zwicky Transient Facility collaboration
on 22 May 2019; 23:34 UT
Credential Certification: Eric Bellm (ecbellm@uw.edu)
Subjects: Optical, Black Hole
The Zwicky Transient Facility (ZTF; Bellm et al 2019, PASP 131, 018002) has identified an outburst from the black hole very faint X-ray transient Swift J1357.2-0933 (Krimm et al. 2011, ATel #3138). Through 26 March 2019, ZTF image differencing did not show significant deviation from its quiescent magnitude (r_ZTF ~ 20.7 mag, g_ZTF ~ 21.3 mag). ZTF detected an brightening to r_ZTF = 17.8 mag at 09:40 UTC on 31 March 2019 and assigned the internal designation ZTF19aanxwrq. Subsequent detections between 9 April and 14 May show a flat lightcurve with r_ZTF ~ g_ZTF ~ 16.9 mag.
Follow-up observations are encouraged.
ZTF is a project led by PI S. R. Kulkarni at Caltech (see ATel #11266), and includes IPAC; WIS, Israel; OKC, Sweden; JSI/UMd, USA; UW, USA; DESY, Germany; MOST, Taiwan; UW Milwaukee, USA and LANL, USA. ZTF acknowledges the generous support of the NSF under AST MSIP Grant No 1440341. Alert distribution service provided by DIRAC@UW. Alert filtering is being undertaken by the GROWTH marshal system, supported by NSF PIRE grant 1545949.
