Matthew J. Richter

Detection of Pure Rotational H2 Emission from the Supernova Remnant IC 443: Further Evidence for a Partially Dissociating J-Shock

We present the first observation of the pure rotational 0-0 S(2) line of H2, at 12.28 μm, from the supernova remnant IC 443. In combination with near infrared observations, the pure rotational emission effectively differentiates between broad classes of shock model. A J-shock, in which H2 is partially dissociated, propagating into gas with H2 density of 4 × 103 cm-3 provides a good fit to the observed H2 level populations but cannot be reconciled with the shock velocity inferred from H2 line profiles. The relative H2 level population in IC 443 and Orion Peak 1, discovered to be essentially identical for upper state energies E/k > 6000 K by Richter, Graham, and Wright, is identical for the 0-0 S(2) line at E/k = 1681.6 K, suggesting that the underlying nature of the two shocks as traced by H2 observations is identical.

MICHI: a thermal-infrared instrument for the TMT

With the imminent launch of the JWST, the field of thermal-infrared (TIR) astronomy will enjoy a revolution. It is easy to imagine that all areas of infrared (IR) astronomy will be greatly advanced, but perhaps impossible to conceive of the new vistas that will be opened. To allow both follow-up JWST observations and a continuance of work started on the ground-based 8m’s, we continue to plan the science cases and instrument design for a TIR imager and spectrometer for early operation on the TMT. We present the current status of our science cases and the instrumentation plans, harnessing expertise across the TMT partnership. This instrument will be proposed by the MICHI team as a second-generation instrument in any upcoming calls for proposals.

Water Vapor in the Outer Atmospheres of Red Giants Probed by High-Resolution, Mid-Infrared Observations

Here, we report on our detection of water vapor in the mid-infrared (11-12 microns) spectrum of the Kl.5 giant Arcturus (α Boo) obtained with the high-resolution, infrared spectrograph TEXES. The detection is presented in detail in Ryde et al. 2002 ApJ, submitted. We are successful in modeling several resolved, rotational lines of water vapor and vibration-rotational (1.5 microns) and rotational lines of OH with a modified MARCS photosphere