Related papers: Arm Structure in Anemic Spiral Galaxies
Passive spiral galaxies - unusual galaxies with spiral morphologies but without any sign of on-going star formation - have recently been shown to exist preferentially in cluster infalling regions. This discovery directly connects passive…
Although more than two-thirds of star-forming disk galaxies in the local universe are barred, some galaxies remain un-barred, occupying the upper half of the Hubble tuning fork diagram. Numerical simulations almost always produce bars…
We present an analysis of the gas dynamics of star-forming galaxies at z~1.5 using data from the KMOS Galaxy Evolution Survey (KGES). We quantify the morphology of the galaxies using $HST$ CANDELS imaging parametrically and…
Star formation is enhanced in spiral arms because of a combination of orbit crowding, cloud collisions, and gravitational instabilities. The characteristic mass for the instability is 10^7 Msun in gas and 10^5 Msun in stars, and the…
The causes of spiral structure in galaxies remain uncertain. Leaving aside the grand bisymmetric spirals with their own well-known complications, here we consider the possibility that multi-armed spiral features originate from density…
Aims: Density waves are often considered as the triggering mechanism of star formation in spiral galaxies. Our aim is to study relations between different star formation tracers (stellar UV and near-IR radiation and emission from HI, CO and…
The Cold Neutral Medium (CNM) is an important part of the galactic gas cycle and a precondition for the formation of molecular and star forming gas, yet its distribution is still not fully understood. In this work we present extremely high…
Spiral arms are the most characteristic features of disc galaxies, easily distinguishable due to their association with ongoing star formation. However, the role of spiral structure in the chemical evolution of galaxies is unclear. Here we…
We have conducted a study of optical and HI properties of spiral galaxies (size, luminosity, H-alpha flux distribution, circular velocity, HI gas mass) to investigate causes (e.g., nature versus nurture) for variation within the cluster…
We analyze the dependence of disk morphology (arm class, Hubble type, bar type) of nearby spiral galaxies on the galaxy environment by using local background density ($\Sigma_{n}$), projected distance ($r_{p}$), and tidal index ($TI$) as…
We analyze a morphologically-selected complete sample of 52 late-type (spiral and irregular) galaxies in the Hubble Deep Field North with total K-magnitudes brighter than K=20.47. This sample exploits in particular the ultimate imaging…
Tidal encounters are believed to be one of the key drivers of galactic spiral structure in the Universe. Such spirals are expected to produce different morphological and kinematic features compared to density wave and dynamic spiral arms.…
Spiral arms are one of the most important features used to classify the morphology of local galaxies. The cosmic epoch when spiral arms first appeared contains essential clues to the evolution of disk galaxies. In this letter, we used James…
We discuss the properties of the HI in low-luminosity early-type galaxies. The morphology of the HI is more regular than that of the HI in many more-luminous early-type galaxies. The HI is always distributed in a disk and is more centrally…
We discuss a possible delay experienced by protogalaxies with low column density of gas in forming stars over large scales. After the hydrogen has recombined, as the external ionizing UV flux decreases and the metal abundance $Z$ increases,…
Spiral arms are some of the most spectacular features in disc galaxies, and also present in our own Milky Way. It has been argued that star formation should proceed more efficiently in spiral arms as a result of gas compression. Yet,…
High resolution N-body simulations using different codes and initial condition techniques reveal two different behaviours for the rotation frequency of transient spiral arms like structures. Whereas unbarred disks present spiral arms nearly…
Galaxy-wide star formation can be quenched by a number of physical processes such as environmental effects (e.g., ram pressure stripping) and supernova feedback. Using numerical simulations, we here demonstrate that star formation can be…
We study the Kennicutt-Schmidt relation between average star formation rate and average cold gas surface density in the Hi dominated ISM of nearby spiral and dwarf irregular galaxies. We divide the galaxies into grid cells varying from…
Recent observations with the IRAM instruments have allowed to explore the star formation efficiency in galaxies as a function of redshift, in detecting and mapping their molecular gas. Some galaxies stand on what is called the "main…