Special Notice #151: Monitoring of the neutron star binary SDSS J102347.68+003841.2 [AY Sex]
AAVSO Special Notice #151
Alert Notice 354: Extending Request to Observe HMXBs in Support of Radial Velocity Observations
HMXB campaign extended until further notice. It has been updated numerous times and covered in AAVSO Alert Notices 348, 354, and 377, and in AAVSO Special Notices #118, #129, #143, #213, and #220.
Alert Notice 397: Request for optical photometry of the bright X-ray binary V884 Sco (4U 1700-377)
June 30, 2009
Dr. Jerome Orosz (SDSU) has requested the assistance of southern bright star observers in observing the high-mass X-ray binary star V884 Sco (== 4U 1700-377). Orosz and collaborators are attempting to measure the mass of the compact object to clarify whether the object is a black hole or a neutron star. Optical photometry of the ellipsoidal variations of V884 Sco will be used in conjunction with optical spectroscopy to be performed at Las Campanas in mid-July and early August 2009 to measure the dynamical properties of the system.