Kinematics of the ionized hydrogen in the irregular galaxy NGC 4449

Journal Article · Sun Jun 01 04:00:00 EDT 1986 · Astron. J.; (United States)

DOI:https://doi.org/10.1086/114105· OSTI ID:5199073

Malumuth, E M; Williams, T B; Schommer, R A

A Fabry-Perot imaging interferometer has been used to determine the velocity and velocity-dispersion fields of the ionized gas in the LMC-type irregular galaxy NGC 4449. In addition to the previously known H II regions and filaments, an extensive system of diffuse, low-intensity H-alpha emission is found throughout the galaxy. The velocities of the bright H II regions in the barlike region of the galaxy are in good agreeemnt with published velocities. The diffuse gas in the bar as well as the H II regions indicate a rotation of about + or - 15 km/s. The regions of highest and lowest velocities are in the diffuse gas off of the bar. In at least two places these regions end just at the edge of the bar. The velocities and velocity dispersions are in qualitative agreement with a spherical patchy inflow of gas from a large H I cloud that surrounds the galaxy. 20 references.

• Research Organization: Rutgers Univ., Piscataway, NJ
• OSTI ID: 5199073
• Journal Information: Astron. J.; (United States), Journal Name: Astron. J.; (United States) Vol. 91; ISSN ANJOA
• Country of Publication: United States
• Language: English

Related Subjects

640105* -- Astrophysics & Cosmology-- Galaxies
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CHARGED PARTICLES
COSMIC RADIO SOURCES
EMISSION SPECTRA
FLUIDS
GALAXIES
GASES
H2 REGIONS
HYDROGEN IONS
IONIZED GASES
IONS
MILKY WAY
SPECTRA
VELOCITY