NOAO >   Observing Info >   Approved Programs >   2011A-0475

Small NOAO Logo

Proposal Information for 2011A-0475


PI: Valerie Mikles, Louisiana State University, vmikles@phys.lsu.edu
Address: Department of Physics & Astronomy, 202 Nicholson Hall Tower Dr., Baton Rouge, LA 70803-4001, United States of America

CoI: Robert Hynes, Louisiana State University

Title: Measuring the Mass of the Neutron Star Sco X-2 = GX 349+2

Abstract: We will study the neutron star low-mass X-ray binary Sco X-2 = GX 349+2 using GMOS on Gemini-S. Our goal is to measure the motion of reprocessed NIII and CIII lines from the companion star and hence derive the mass function and establish a solid lower limit of the mass of the neutron star in this system. This technique has been applied successfully to several related objects, but GX 349+2 stands out as lacking in any phase resolved spectroscopic study, despite being reasonably bright and having a well-defined period from photometry. Since GX 349+2 accretes mass at near the maximum theoretical rate, we expect the neutron star mass to be on the higher end of the neutron star mass distribution. By probing the most massive neutron stars, we can better constrain the equation of state of the extremely dense matter comprising these exotic objects.


National Optical Astronomy Observatory, 950 North Cherry Avenue, P.O. Box 26732, Tucson, Arizona 85726, Phone: (520) 318-8000, Fax: (520) 318-8360



NOAO >   Observing Info >   Approved Programs >   2011A-0475

noaoprop-help@noao.edu

Small NOAO Logo