Circumgalactic H-alpha Spectrograph: Performance, Target Selection, and Scattered Light Analysis
Abstract
CHaS, or the Circumgalactic H-alpha Spectrograph (CHaS), is a ground-based instrument in development to study the circumgalactic medium (CGM) of galaxies in the local universe, and to understand the role that the CGM plays in galaxy formation and evolution. CHaS is being deployed on the MDM Hiltner 2.4m telescope, on Kitt Peak, Arizona. In preparation for initial observing runs, taking place in early 2020, we have been modeling the spectrograph performance, and using this model to determine the initial list of candidate galaxies to target in H-alpha. Our model includes actual H-alpha images and velocity fields taken by other recent surveys as well as a theoretically motivated model of the extended CGM. As part of this effort, we are modeling the scattered light contribution from bright H-alpha emission produced in the galactic disk. This is an important background contribution, which must be understood to confirm a likely tenuous emission detection from the CGM. Finally, we describe the development of MicroCHaS, an outreach component of the spectrograph effort.
- Publication:
-
American Astronomical Society Meeting Abstracts #235
- Pub Date:
- January 2020
- Bibcode:
- 2020AAS...23517528G