BVRI Surface Photometry of Isolated Spiral Galaxies

TL;DR

This study provides multicolor BVRI photometry and structural analysis of 44 isolated spiral galaxies, revealing their morphological features, bar structures, and how their properties differ from interacting galaxies, aiding galaxy evolution research.

Contribution

It offers the first comprehensive BVRI photometry and CAS structural parameters for a well-defined sample of isolated spirals, including detailed morphological reevaluation and bar analysis.

Findings

63% of galaxies have well-identified optical/near-IR bars.

Half of the galaxies show rings.

Isolated spirals differ from interacting ones in the A-S structural plane.

Abstract

A release of multicolor broad band (BVRI) photometry for a subsample of 44 isolated spirals drawn from the Catalogue of Isolated Galaxies (CIG) is presented. Total magnitudes and colors at various circular apertures, as well as some global structural/morphological parameters are estimated. Morphology is reevaluated through optical and sharp/filtered R band images, (B-I) color index maps, and archive near-IR JHK images from the Two-Micron Survey. The CAS structural parameters (Concentration, Asymmetry, and Clumpiness) were calculated from the images in each one of the bands. The fraction of galaxies with well identified optical/near-IR bars (SB) is 63%, while a 17% more shows evidence of weak or suspected bars (SAB). The sample average value of the maximum bar ellipticity is 0.4. Half of the galaxies in the sample shows rings. We identify two candidates for isolated galaxies with disturbed morphology. The structural CAS parameters change with the observed band, and the tendencies they follow with the morphological type and global color are more evident in the redder bands. In any band, the major difference between our isolated spirals and a sample of interacting spirals is revealed in the A-S plane. A deep and uniformly observed sample of isolated galaxies is intended for various purposes including (i) comparative studies of environmental effects, (ii) confronting model predictions of galaxy evolution and (iii) evaluating the change of galaxy properties with redshift.