NGC 4102: High Resolution Infrared Observations of a Nuclear Starburst Ring

Abstract

The composite galaxy NGC 4102 hosts a LINER nucleus and a starburst. We mapped NGC 4102 in the 12.8 micron line of [NeII], using the echelon spectrometer TEXES on the NASA IRTF, to obtain a data cube with 1.5" spatial and 25 km/s spectral, resolution. Combining near-infrared, radio, and the [NeII] data shows that the extinction to the starburst is substantial, more than 2 magnitudes at K band, and that the neon abundance is less than half solar. We find that the star formation in the nuclear region is confined to a rotating ring or disk of 4.3" (~300 pc) diameter, inside the Inner Lindblad Resonance. This region is an intense concentration of mass, with a dynamical mass of ~3 x 10^9 solar masses, and of star formation. The young stars in the ring produce the [NeII] flux reported by Spitzer for the entire galaxy. The mysterious blue component of line emission detected in the near-infrared is also seen in [NeII]; it is not a normal AGN outflow.

submitted to ApJ

References in corpus (3)

• The Mid-infrared Fine-structure Lines of Neon as an Indicator of Star For mation Rate in Galaxies
• Mid-Infrared Diagnostics of LINERs
• [Ne II] Observations of Gas Motions in Compact and Ultracompact H II Regions

Cited by in corpus (4)

• Suzaku observation of the LINER NGC 4102
• Ionized Gas Kinematics at High Resolution. II: Discovery of a Double Infrared Cluster in II Zw 40
• Ionized Gas Kinematics at High Resolution V: [NeII], Multiple Clusters, High Efficiency Star Formation and Blue Flows in He 2-10
• Ionized Gas Kinematics at High Resolution IV: Star Formation and a Rotating Core in the Medusa (NGC 4194)