skip to main content

Title: INVESTIGATING DISK-HALO FLOWS AND ACCRETION: A KINEMATIC AND MORPHOLOGICAL ANALYSIS OF EXTRAPLANAR H I IN NGC 3044 AND NGC 4302

To further understand the origins of and physical processes operating in extra-planar gas, we present observations and kinematic models of H I in the two nearby, edge-on spiral galaxies NGC 3044 and NGC 4302. We model NGC 3044 as a single, thick disk. Substantial amounts of extra-planar H I are also detected. We detect a decrease in rotation speed with height (a lag) that shallows radially, reaching zero at approximately R {sub 25}. The large-scale kinematic asymmetry of the approaching and receding halves suggests a recent disturbance. The kinematics and morphology of NGC 4302, a Virgo Cluster member, are greatly disturbed. We model NGC 4302 as a combination of a thin disk and a second, thicker disk, the latter having a hole near the center. We detect lagging extra-planar gas, with indications of shallowing in the receding half, although its characteristics are difficult to constrain. A bridge is detected between NGC 4302 and its companion, NGC 4298. We explore trends involving the extra-planar H I kinematics of these galaxies, as well as galaxies throughout the literature, as well as possible connections between lag properties with star formation and environment. Measured lags are found to be significantly steeper than those modeled by purely ballistic effects, indicating additional factors.more » Radial shallowing of extra-planar lags is typical and occurs between 0.5R {sub 25} and R {sub 25}, suggesting internal processes are important in dictating extra-planar kinematics.« less
Authors:
 [1] ;  [2] ;  [3]
  1. Max Planck Institute for Astronomy, Königstuhl 17, D-69117 Heidelberg (Germany)
  2. Department of Physics and Astronomy, University of New Mexico, 1919 Lomas Boulevard NE, Albuquerque, NM 87131 (United States)
  3. Department of Astronomy, New Mexico State University, P.O. Box 30001, MSC 4500, Las Cruces, NM 88003 (United States)
Publication Date:
OSTI Identifier:
22364478
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 799; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; APPROXIMATIONS; ASYMMETRY; COMPUTERIZED SIMULATION; DISTURBANCES; GALAXIES; GALAXY CLUSTERS; HYDROGEN 1; MORPHOLOGY; ORIGIN; ROTATION; STAR CLUSTERS; STAR EVOLUTION; STARS; VELOCITY