none

NRAO/Socorro Colloquium Series

John Bally

University of Colorado at Boulder

Stellar Feedback and the Ecology of the Galactic ISM

Large-scale surveys of the Milky Way complemented by high-resolution studies of small fields are revolutionizing our understanding of the Galactic interstellar medium (ISM) and star formation.  There are no “initial conditions” for star formation.   Every state of the ISM is dynamic and an evolutionary consequence of a prior state in the Galactic Ecology powered by a combination of galactic processes (spiral arms, the bar, etc.) and super-bubbles created by massive star-clusters and OB associations.

I will describe the feedback ladder – a chain of increasingly powerful mechanisms consisting of protostellar outflows, FUV and EUV radiation, radiation pressure, and stellar winds and  supernovae.  The feedback ladder regulates cloud properties (turbulence, lifetime) and may play a major role in determining the stellar initial mass function (IMF), the star formation efficiency (SFE), and on its highest rung, responsible for the Galactic ecology. 



November 9, 2012
11:00 am

Array Operations Center Auditorium

All NRAO employees are invited to attend via video, available in Charlottesville Room 230, Green Bank Room 137 and Tucson N525.

Local Host: Miller Goss

Connect with NRAO

The National Radio Astronomy Observatory and Green Bank Observatory are facilities of the U.S. National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Founded in 1956, the NRAO provides state-of-the-art radio telescope facilities for use by the international scientific community. NRAO telescopes are open to all astronomers regardless of institutional or national affiliation. Observing time on NRAO telescopes is available on a competitive basis to qualified scientists after evaluation of research proposals on the basis of scientific merit, the capability of the instruments to do the work, and the availability of the telescope during the requested time. NRAO also provides both formal and informal programs in education and public outreach for teachers, students, the general public, and the media.

The National Science Foundation (NSF) is an independent federal agency created by Congress in 1950 "to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense..."

AUI collaborates with the scientific community and research sponsors to plan, build, and operate cutting-edge facilities. We cultivate excellence, deliver value, enhance education, and engage the public.