Starlight morphology of the interacting galaxy NGC 5195

Details Starlight morphology of the interacting galaxy NGC 5195 Starlight morphology of the interacting galaxy NGC 5195

Oct 1990

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1990apj...362..455s&link_type=abstract

Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 362, Oct. 20, 1990, p. 455-467. Research supported by NASA, USAF, and Unive

Astronomy and Astrophysics

Astronomy

20

Astronomical Models, Astronomical Spectroscopy, Galactic Nuclei, Galactic Structure, Near Infrared Radiation, Interstellar Matter, Morphology, Star Formation, X Ray Astronomy, Galaxies: Individual (Ngc 5194) (Ngc 5195) Galaxies: Interactions, Galaxies: Photometry, Galaxies: Structure

Scientific paper

We present near-infrared, red, and optical observations of NGC 5195, the interacting companion of NGC 5194 (M51). Three intrinsic components are suggested by the near-infrared data: a bright nuclear maximum, a low-contrast bar centered symmetrically on the nucleus, and a nearly face-on exponential disk. This organized near-infrared morphology contrasts strongly with the irregular appearance of optical images. Neither dust nor hot stars contribute much to the near-infrared emission, leaving cool stars probably of an evolved population as the main near-infrared sources.
Optical (V) and red (R, I) images confirm the near-infrared morphology and imply that obscuration by an irregular distribution of dust causes the great difference between optical and near-infrared morphologies. Dust within a foreground spiral arm of M51 is an important source of obscuration. Dust internal to NGC 5195 gives an observed quantity of reradiation and perhaps contributes significant obscuration within 10" of the galactic nucleus. The nucleus itself lies at or near a local minimum in color produced by small obscuration or possibly hot emission from the galaxy's nuclear emission-line region or X-ray medium. When corrected for all spatial components of extinction, the body of NGC 5195 becomes much bluer and has a mean B - H color common to normal disk galaxies.
Observations lead consistently to SB, but no further, as the best description of the NGC 5195 morphology. Images reveal no evidence of spiral arms which alone would imply a lenticular subtype. Yet the bulge-to-disk ratio of NGC 5195, evaluated from near-infrared observations, is far smaller than values inferred for noninteracting lenticular galaxies. Motivated by these difficulties in conventional classification, we proceed to discuss the possibility that certain attributes of NGC 5195, including its bar, are transient manifestations of the interaction with M51.
Presented measurements support the galaxy mass ratio and type of NGC 5195 morphology assumed in a successful model of the gravitational interaction between stars of M51 and NGC 5195. Encouraged by this agreement between theory and experiment, we explore the consequences of an expanded version of the model, still premised on interaction via gravity but now including dynamics of both stars and interstellar clouds. Working within this theoretical context, we identify an interaction-induced component of star formation, an incipient starburst, within the disk of M51.

Affiliated with

Also associated with

No associations

Rating

Starlight morphology of the interacting galaxy NGC 5195 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Starlight morphology of the interacting galaxy NGC 5195, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Starlight morphology of the interacting galaxy NGC 5195 will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1302375