RUI: The Unique Microquasar SS 433 - An Optical Program and Contribution to a Multiwavelength Collaborative Study

Valparaiso University, Valparaiso IN

Investigators

Abstract

The overall goal of this research is a better understanding of the nature of the Galactic microquasar SS 433 - an object which possesses many of the characteristics of a quasar such as a hot disk, a strong disk wind, evidence for a compact object, and relativistic jets. However, because it is a Galactic object, it is closer and is not obscured by a galaxy of material surrounding it, thereby providing an opportunity to explore important but poorly understood physics. Specific goals here are to identify the nature of the compact object in SS 433 (is it a neutron star or black hole?), to examine the structure and origin of the relativistic jets, and to accurately assess the system's evolutionary state. This will be accomplished through a multiwavelength campaign using simultaneous radio imaging and optical plus x-ray spectroscopy to study the disk and jet in SS 433. Through this, the motion of the relativistic jet will be followed, the time and distance scale of jet fragmentation determined, the disappearance of optical jet lines monitored, and the true space velocities of the jets will be found. In addition, optical spectroscopy will be used to study the jet, mass donor star, and the compact object. It is expected that the mass of the donor star will be conclusively determined as well as its evolutionary state. Finally, the observations should also provide the mass of the compact object thereby revealing whether it is a black hole or a neutron star. Through this award, the research infrastructure at Valparaiso will be improved in part by creating new student research opportunities. Participating students will serve as research assistants during ten weeks each summer and will be trained in aspects of astronomical data acquisition, reduction, and analysis. They will have the opportunity to present their results at national conferences and to co-author referred journal articles. Dr. Hillwig's work in SS 433 has also been featured in many popular articles and he will continue to pursue public dissemination of the results in the press and through public talks.