Optical Outburst of V4641 (=SAX J1819.3-2525)
ATel #170; M. Buxton (Yale), D. Maitra (Yale), C. Bailyn (Yale), L. Jeanty (Yale), D. Gonzalez (CTIO)
on 4 Aug 2003; 22:31 UT
Credential Certification: Dipankar Maitra (maitra@astro.yale.edu)
Subjects: Optical, Binary, Black Hole, Transient
Referred to by ATel #: 172, 175
SMARTS consortium observations of the black hole candidate V4641 Sgr
with the 1.3m telescope at CTIO + ANDICAM instrument from UT 2003
Aug 4.00 indicate that the source is starting a new outburst. The
B, V, and I magnitudes were 12.8, 12.6 and 12.2, which is 1.1, 1.1 and 1.1
magnitudes above the predicted quiescent value. I-band data
folded on the orbital period show activity as early as
UT 2003 Aug 1.95. Observations at all wavelengths are encouraged.
Our recent optical data from SMARTS are posted at http://phoenix.astro.yale.edu/buxton/smarts/v4641_2003outburst.html
V4641 optical outburst of 2003