The Frequency of Barred Spiral Galaxies in the Near-Infrared

Abstract

We have determined the fraction of barred galaxies in the H-band for a statistically well-defined sample of 186 spirals drawn from the Ohio State University Bright Spiral Galaxy survey. We find 56% of our sample to be strongly barred at H, while another 16% is weakly barred. Only 27% of our sample is unbarred in the near-infrared. The RC3 and the Carnegie Atlas of Galaxies both classify only about 30% of our sample as strongly barred. Thus strong bars are nearly twice as prevalent in the near-infrared as in the optical.The frequency of genuine optically hidden bars is significant, but lower than many claims in the literature: 40% of the galaxies in our sample that are classified as unbarred in the RC3 show evidence for a bar in the H-band, while for the Carnegie Atlas this fraction is 66%. Our data reveal no significant trend in bar fraction as a function of morphology in either the optical or H-band.Optical surveys of high redshift galaxies may be strongly biased against finding bars, as bars are increasingly difficult to detect at bluer rest wavelengths.

Constraints from Dynamical Friction on the Dark Matter Content of Barred Galaxies

“…If all of the halo angular momentum arises from tidal torques in the early universe, the required value of j would be reached only rarely (Barnes & Efstathiou 1987 ;Steinmetz & Bartelmann 1995). Since of Z50% all high surface brightness (HSB) disks contain strong bars (Eskridge et al 2000), the vast majority cannot have j large enough to avoid bar slowdown.…”

“…Here we present an argument that DM halos have the lowest possible central density consistent with not being hollow. Following van Albada & Sancisi (1986), we refer to such minimum halo models as "" maximum disks.ÏÏ Strong bars are seen in optical images of roughly 30% of all disk galaxies (Sellwood & Wilkinson 1993), and this fraction rises to over 50% in the near-IR (Eskridge et al 2000). Their presence makes them ideal probes of the dynamics of the central regions.…”

Frequency and properties of bars in cluster and field galaxies at intermediate redshifts

“…While it is still unknown why a specific disk galaxy hosts a bar and an apparently similar galaxy is unbarred, it is clear that a significant fraction of bright disk galaxies appears barred in optical observations (Eskridge et al 2000;Marinova & Jogee 2007;Reese et al 2007;Barazza et al 2008). In studies carried out in the near-infrared (NIR) or in both, NIR and optical, the NIR bar fractions are typically higher (Knapen 1999;Eskridge et al 2000;Laurikainen et al 2004;Menéndez-Delmestre et al 2007;Marinova & Jogee 2007).…”

“…In studies carried out in the near-infrared (NIR) or in both, NIR and optical, the NIR bar fractions are typically higher (Knapen 1999;Eskridge et al 2000;Laurikainen et al 2004;Menéndez-Delmestre et al 2007;Marinova & Jogee 2007). These findings indicate that bar detection is affected by dust extinction and that studies completed at different wavelengths cannot be readily compared.…”

“…The most straightforward approach is to inspect images visually and assign a bar class (e.g., weak/strong bars) to each galaxy (de Vaucouleurs et al 1991;Eskridge et al 2000). By adopting this approach, strong bars were detected twice as frequently in near-infrared data than optical data (Eskridge et al 2000) and the bar fraction was found to increase between Sc galaxies and later types (Odewahn 1996).…”