2004ApJ...615..880B

We obtained simultaneous optical and near-infrared observations of 4U 1543-47 during its 2002 outburst. The most striking feature of the outburst light curve is the secondary maximum, which appears after the object transitions into the low-hard state. This secondary maximum is much stronger in the infrared bands than in the optical. We suggest that the origin of the secondary maximum flux may be synchrotron radiation associated with a jet. Close infrared monitoring may lead to reliable triggers for simultaneous multiwavelength campaigns to study jet formation processes.