CRTS-II discovery of an outburst of BH transient Swift J1357.2-0933
ATel #10297; A. J. Drake, S. G. Djorgovski, A. A. Mahabal, M. J. Graham (Caltech); D. Stern (JPL); M. Catelan (PUC Chile); E. Christensen, S. M. Larson (LPL/UA).
on 20 Apr 2017; 23:16 UT
Credential Certification: Andrew J. Drake (ajd@cacr.caltech.edu)
Subjects: Optical, Binary, Transient
On 2017-04-20.33 UT CRTS-II detected an optical outburst of short period
black hole transient (BHT) candidate Swift J1357.2-0933 (Krimm et al. 2011,
ATel#3138; Rau et al. 2011, ATel#3140; Sanchez et al. 2015, MNRAS, 454, 2199).
From four observations taken with the Catalina Schmidt telescope plus 19 sq. deg.
camera, the source was measured as having V_CSS=16.7+/-0.1. The quiescent brightness
is V_CSS~21.
The 2011 outburst of Swift J1357.2-0933 was independently detected by CRTS as
transient CSS110208:135717-093238, and was spectroscopically determined to
have a featureless blue continuum (Drake et al. 2011, ATel#3343; Drake et al. 2014,
MNRAS, 441, 1186). At that time Swift J1357.2-0933 was measured to peak at V_CSS~16.2,
with the outburst lasting >170 days.
Additional information regarding Swift J1357.2-0933 is given in the catalog of
stellar-mass black holes in X-ray binaries, BlackCAT (www.astro.puc.cl/BlackCAT,
Corral-Santana et al. 2016, A&A, 587, 61).
Optical and spectroscopic follow-up are requested.
All CRTS-II and CRTS discoveries are publicly available via the CRTS home page
(crts.caltech.edu).
