María José Martín Sempere

Are isolated galaxies boring

We have elaborated a well defined and statistically significant sample of isolated galaxies in order to interpret the role of environment on galaxy structure and evolution. In particular, we are building a multiwavelength database for this sample to compare and quantify the properties of different phases of the ISM. Our currently refined Catalog of Isolated Galaxies (based on CIG; Karachentseva, 1973) contains 754 galaxies with redshift and FIR (IRAS) data, and satisfies the following requirements better than any other existing sample. 1) Isolation: selected on the basis of the distance to the nearest similarly sized galaxies. 2) Morphology: The CIG sample is morphologically diverse and large enough to permit discrimination on the basis of galaxy type. POSS-based classifications exist for the entire catalog. 3) Depth: The CIG surveys a large enough volume of space to allow us to sample a large part of the optical and FIR luminosity functions. 4) Completeness: sample is reasonably complete out to V0 = 10000 km/s. A test yields a value of 0.42 down to m B = 15.7 mag.

Two Decoupled Bars in the Spiral Galaxy NGC 3359

We present self-consistent numerical simulations of the molecular gas in the spiral galaxy NGC 3359. Using the real potential derived from an I-band image, we have tried to find the dynamical parameters able to account for the observed gas kinematics and morphology (in both Ha and HI). The best result is obtained for a two pattern speeds model: the central region (up to ~ 15”), corresponding to a nuclear bar, rotates with an Ω p = 100 km s-1 kpc -1.The outer bar+spiral, decoupled from the nuclear region, has a slower angular velocity Ω p = 27 km s-1 kpc -1. The model reproduces the complex Hα structure in the inner 20” radius, which is certainly not fitted with the one mode pattern.