A Lifetime of Influence: Abstracts, Talks, and Posters
 

Remarkable X-ray Emission from the Young O4-O4 Binary in M17

Leisa Townsley
Penn State University

The Chandra X-ray Observatory, with its sub-arcsecond spatial resolution and hard X-ray response, is an excellent probe of massive star formation and feedback and will remain the only sub-arcsecond X-ray telescope available when ALMA and JWST come on-line. Chandra is revealing that very young massive stars are often hard X-ray emitters, in addition to standard expectations of soft X-rays due to microshocks in their fast winds. These unexpected hard X-rays may come from magnetically-channeled wind shocks around magnetic O stars, but in some cases there is compelling evidence that colliding winds from binary O stars are the cause. To add to the mystery, Chandra shows that these hard X-rays are not present in cluster O stars aged more than about 2 million years -- do fossil B fields die away, or are massive binary systems somehow disrupted early on? Whatever the cause, these hard X-rays can reveal early stages of massive star formation behind 150 magnitudes of visual extinction and from half-way across the Galaxy.