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NRAO/Socorro Colloquium Series

Patrick Hartigan

Rice University

Dynamics of Stellar Jets Revealed Though Phase Space

When low mass stars form they are typically surrounded by dense disks of gas and dust. Accretion of disk material onto the star drives a collimated supersonic jet that generates shock waves along its length as fast jet material overtakes slower gas. As the resulting bow shocks and internal shocks cool, jets radiate brightly in emission lines. By combining high-resolution imaging and spatially-resolved spectroscopy, it is possible to obtain a datacube of spectra vs. position for each emission line. The emission lines are optically thin, so typical nebular diagnostics uncover physical conditions
such as density, ionization fraction and temperature as functions of both position and velocity. In addition, knots in the jets show proper motions, so time-series analysis is feasible.

This talk will summarize recent results from Hubble movies of stellar jets, Hubble slitless spectra, and Keck longslit position-velocity diagrams from the standpoint of physical conditions and dynamics.
There are also intriging possibilities to learn more about the dynamics from ongoing scaled laboratory experiments.



October 19, 2013
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: Huib Intema

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