Long-slit Space Telescope Imaging Spectrograph (STIS) observations of the nuclear region of M51 have been obtained to study to kinematic and ionization structure of multiple resolved emission line clouds in the narrow line region (NLR). These spectra were obtained through a 52'' x 0.2'' slit at a single position angle (166o) intesecting the nucleus and several NLR clouds, and cover the spectral range from 2900 Angstroms to 1 micron. Emission from [OII], Hβ , [OIII], Hα , [NII], and [SII] is detected for the nine resolved clouds within 2.5'' ( 120 pc for D=9.6 Mpc) of the nucleus. Individual cloud velocities, velocity dispersions, and flux ratios will be presented to explore the physical conditions (temperature, density, ionization state) of the NLR gas. We will examine the relative importance of photoionization and collisional shock wave heating in these clouds. This work has been supported by NASA contract NAS5-30403.
American Astronomical Society Meeting Abstracts
- Pub Date:
- December 1999