Related papers: Very Cold Gas and Dark Matter
Molecular gas has been searched for and found in unexpectedly large quantities in some collisional debris of interacting galaxies: HI-rich tidal tails, bridges and collisional rings. It was so far observed through millimeter observations of…
The bulk of the molecular component in galaxies is made of cold H2, which is not observed directly, but which abundance is derived from indirect tracers such as CO emission. The CO to H2 conversion ratio remains uncertain, and may vary by…
The results of a CO line survey in central cluster galaxies with cooling flows are presented. Cold molecular gas is detected with the IRAM 30m telescope, through CO(1-0) and CO(2-1) emission lines in 6-10 among 32 galaxies. The…
The bulk of the molecular gas in spiral galaxies is under the form of cold H2, that does not radiate and is only suspected through tracer molecules, such as CO. All tracers are biased, and in particular H2 could be highly underestimated in…
Robust knowledge of molecular gas mass is critical for understanding star formation in galaxies. The H$_{2}$ molecule does not emit efficiently in the cold interstellar medium, hence the molecular gas content of galaxies is typically…
We describe an extensive FUSE survey of highly ionized oxygen in the vicinity of the Milky Way that serves as an example of the type of study that would be desirable for other galactic systems. Understanding the origin of hot gas in the…
I present an overview of some of the recent advances in our understanding of the distribution and evolution of the ordinary, baryonic matter in the universe. Two observations that strongly suggest that most of the baryons seen at high…
The content of interstellar clouds, in particular the inventory of diffuse molecular gas, remains uncertain. We identified a sample of isolated clouds, approximately 100 solar masses in size, and used the dust content to estimate the total…
Over the last decade, observations of the cool interstellar medium in distant galaxies via molecular and atomic fine structure line emission has gone from a curious look into a few extreme, rare objects, to a mainstream tool to study galaxy…
We present an analysis of the Far Ultraviolet Spectroscopic Explorer (FUSE) spectrum of HD141569A, a transitional object known to possess a circumstellar disk. We observe two components of gas at widely different temperatures along the line…
The conjecture that dark matter in galaxies is mostly cold fractal gas is developed in the more general context of the thermodynamics of the ideal isothermal gas subject to gravitational instability. This simple gas model already contains…
New and archival interferometric 12CO(1->0) datasets from six nearby galaxies are combined with H_2 2.122um and H-alpha maps to explore in detail the interstellar medium in different star-forming galaxies. We investigate the relation…
We discuss a supersymmetric model for cogenesis of dark and baryonic matter where the dark matter (DM) has mass in the 8-10 GeV range as indicated by several direct detection searches including most recently the CDMS experiment with the…
Measuring the density profile and mass concentration of dark-matter haloes is a key test of the standard cold dark matter paradigm. Such objects are dark and thus challenging to characterise, but they can be studied via gravitational…
A comet-like, but magnitudes smaller, extremely low albedo interstellar meteoroid population of fragile aggregates with solar type composition, measured in space and terrestrially, is most probably the universal dark matter. Although…
We show that hidden hot dark matter, hidden-sector dark matter with interactions that decouple when it is relativistic, is a viable dark matter candidate provided it has never been in thermal equilibrium with the particles of the standard…
The mass of prestellar cores is an essential ingredient to understand the onset of star formation in the core. The low level of emission from cold dust may keep parts of it hidden from observation. We aim to determine the fraction of core…
The nonbaryonic dark matter of the Universe can consist of new stable charged leptons and quarks, if they are hidden in elusive "dark atoms" of composite dark matter. Such possibility can be compatible with the severe constraints on…
I review recent observations of molecular gas in the halo of the Milky Way and in the Magellanic Clouds. Far-ultraviolet absorption line studies of molecular hydrogen (H_2) with ORFEUS and FUSE have unveiled the presence of a diffuse…
We report a combined experimental and theoretical investigation of near resonance light scattering from a high-density and ultracold atomic $^{87}$Rb gas. The atomic sample, having a peak density $\sim 5\cdot10^{13}$ atoms/cm$^{3}$,…