We have obtained deep CO(1-0) observations of 8 nearby, edge-on, low surface brightness (LSB) spiral galaxies using the NRAO 12-m telescope. We report detections of 3 of our targets at > 4σ level as well as one marginal (∼ 3σ) detection. These are among the first direct detections of molecular gas in late-type, LSB spirals. Using a Galactic CO-to-H2 conversion factor, we derive MH2 ∼ 1.4 − 3.5 ...

We have studied the spectral characteristics of the Diffuse Ionized Gas in two irregular galaxies with low metallicities and intermediate Star Formation Rates: ESO 245-G05 and Gr 8. The [OIII]/Hβ in these galaxies is higher than in the DIG of spiral galaxies but not as high as in other irregular galaxies previously studied, such as IC 10 and NGC 6822. The [NII]/Hα and [SII]/Hα ratios have very ...

We present an analysis of galaxies in the CDF-South. We find a tight relation to z = 3 between color and size at a given mass, with red galaxies being small, and blue galaxies being large. We show that the relation is driven by stellar surface density or inferred velocity dispersion: galaxies with high surface density are red and have low specific star formation rates, and galaxies with low sur...

We present a study of the distribution of AGN in clusters of galaxies with a uniformly-selected, spectroscopically-complete sample of 35 AGN in eight clusters of galaxies at z = 0.06→ 0.31. We find that the 12 AGN with LX > 1042 erg s−1 in cluster members more luminous than a rest-frame MR < −20 mag are more centrally concentrated than typical cluster galaxies of this luminosity, although these...

We have obtained optical CCD spectroscopy along the major axes of 22 nearby spiral galaxies of Sb and Sc types in order to analyze their rotation curves. By subtracting the stellar continuum emission, we have obtained position velocity (PV) diagrams of the Hα and [NII] lines. We point out that the Hα line is often superposed by a broad stellar absorption feature (Balmer wind) in the nuclear reg...

It has been known for a long time that a large fraction of disc galaxies are lopsided. We simulate three different mechanisms that can induce lopsidedness: flyby interactions, gas accretion from cosmological filaments and ram pressure from the intergalactic medium. Comparing the morphologies, HI spectrum, kinematics and m = 1 Fourier components, we find that all of these mechanisms can induce l...

We report on VLA H i spectral line observations of five early-type galaxies classified as optically peculiar because of the presence of jets, ripples, or other optical fine structure. We detect H i within the primary beam (300 half-power beamwidth) in four of the five systems. However, in only one case is this gas associated with the targeted elliptical galaxy. In the other cases the H i is ass...

We study the generation and maintenance of large-scale magnetic fields in barred galaxies. We take a velocity field (with strong noncircular components) from a published gas dynamical simulation of Athanassoula (1992), and use this as input to a galactic dynamo calculation. Our work is largely motivated by recent high quality VLA radio observations of the barred galaxy NGC 1097, and we compare ...