NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-06-19 T17:06:01 PDT
Help | Comment | NED Home

For refcode 1998MNRAS.301..631R:
Retrieve 9 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by Royal Astronomical Society. 1998MNRAS.301..631R Bars and the symmetry of star formation patterns in the discs of spiral galaxies M. Rozas, J. H. Knapen and J. E. Beckman Accepted 1998 June 29. Received 1998 Junc 29: in original form 1997 July l4 ABSTRACT We present a test for the degree of symmetry in the distribution of the Nd brightness along the arms of a sample of spiral galaxies. The test consists of deriving the cross-correlation function of the H{alpha} brightness as a function of curvilinear distance along pairs of opposed arms, after unfolding the arms geometrically. Our results reveal a significantly greater degree of symmetry in the non-barred population than in the barred. We derive parameters for both bar strength and bar ellipticity, and compare these with the derived cross-correlations to strengthen this conclusion. We suggest that density waves are a probable cause for the appearance of global, i.e. disc-wide, two-fold symmetry in spiral discs. Comparison with published work on abundance gradients in the discs of barred and non-barred galaxies indicates that, as for the abundances, mixing in the spiral disc as a result of the bar potential may well be responsible for our observation that stronger bars are related to reduced two-fold symmetry in the distribution of star-forming regions along the spiral arms. Key words: stars: formation - galaxies: spiral - galaxies: structure.
Retrieve 9 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home