State Transitions and MHD Winds In GRO J1655-40
Abstract
During its 2005 outburst, GRO J1655-40 was observed at high spectral resolution with the Chandra HETGS, revealing a spectrum rich with blueshifted absorption lines of elements ranging from oxygen to nickel, including exotic metals like titanium and scandium (Miller et al. 2006, 2008). To date, this spectrum remains the only conclusive observational evidence for magnetically-driven winds in an X-ray binary. Using a second HETGS observation of this microquasar from the very same outburst, we present new results on the origin and structure of the accretion disk wind throughout the outburst. We show how the wind evolves from higher ionization to lower ionization over a period of weeks, as the black hole moves from the jet-launching hard state into a softer state. We address this photoionization evolution in the context of changes in the broadband X-ray spectrum and the role of winds in outburst. We discuss the implications for models of magnetically-driven outflows from black hole binaries.
- Publication:
-
American Astronomical Society Meeting Abstracts #219
- Pub Date:
- January 2012
- Bibcode:
- 2012AAS...21930807N