Related papers: A dynamical transition from atomic to molecular in…
Knowledge of the molecular component of the ISM is fundamental to understand star formation. The H2 component appears to dominate the gas mass in the inner parts of galaxies, while the HI component dominates in the outer parts. Observation…
In this paper we use a number of observations to construct an integrated picture of the ionisation in the interiors of quiescent warm opaque interstellar clouds and in the intercloud medium (ICM) outside dense HII regions and hot dilute…
Cosmic rays (CRs) have critical impacts in the multiphase interstellar medium (ISM), driving dynamical motions in low-density plasma and modifying the ionization state, temperature, and chemical composition of higher-density atomic and…
High-latitude intermediate-velocity clouds (IVCs) are part of the Milky Way's HI halo and originate from either a galactic fountain process or extragalactic gas infall. They are partly molecular and can most of the time be identified in CO.…
{It has recently been proposed that giant molecular complexes form at the sites where streams of diffuse warm atomic gas collide at transonic velocities.} {We study the global statistics of molecular clouds formed by large scale colliding…
Measurements of molecular hydrogen (H_2) column densities are presented for the first six rotational levels (J=0 to 5) for 73 extragalactic targets observed with FUSE. All of these have a final signal-to-noise ratio larger than \snlimit,…
Models that reproduce the observed high-velocity clouds (HVCs) also predict clouds at lower radial velocities that may easily be confused with Galactic disk (|z| < 1 kpc) gas. We describe the first search for these low-velocity halo clouds…
We have obtained high resolution FUSE and HST/STIS echelle observations of the quasar PG 1116+215. The semi-continuous coverage of the ultraviolet spectrum over the wavelength range 916-2800 provides detections of Galactic and high velocity…
This paper presents maps of the J=2-1 transition of CO toward the Draco Nebula Intermediate Velocity Cloud (IVC). The maps cover 8500 square arcmin with a velocity resolution of 0.33 km~s$^{-1}$ and angular resolution of 38", or 0.11 pc at…
We present a wide-field $(60\arcmin \times 30\arcmin)$ study of a dense region within the Polaris Flare, hereafter referred to as the `Polaris molecular cloud', using $^{12}$CO, $^{13}$CO, and C$^{18}$O ($J=1-0$) observations at $20\arcsec$…
We present CO observations of a large sample of ultraluminous IR galaxies out to z = 0.3. Most of the galaxies are interacting, but not completed mergers. All but one have high CO(1-0) luminosities, log(Lco [K-km/s-pc^2]) = 9.92 +/- 0.12.…
The rotational transitions of carbon monoxide (CO) are the primary means of investigating the density and velocity structure of the molecular interstellar medium. Here we study the lowest four rotational transitions of CO towards…
Three dimensional (3D) distribution of the volume-density molecular fraction, defined by fmol_rho=rho_H2/(rho_HI + rho_H2), is studied in the Milky Way Galaxy. The molecular front appears at galacto-centric distance of R \sim 8 kpc, where…
The characteristic mass that sets the peak of the stellar initial mass function (IMF) is closely linked to the thermodynamic behaviour of interstellar gas, which controls how gas fragments as it collapses under gravity. As the Universe has…
Using the far-infrared emission, as observed by the Herschel Virgo Cluster Survey (HeViCS), and the integrated HI and CO brightness, we infer the dust and total gas mass for a magnitude limited sample of 35 metal rich spiral galaxies in…
Recent submillimeter and far-infrared wavelength observations of absorption in the rotational ground-state lines of various simple molecules against distant Galactic continuum sources have opened the possibility of studying the chemistry of…
In this review, I discuss some highlights of recent research on molecular gas in galaxies; large-scale CO maps of nearby galaxies are being made, which extend our knowledge on global properties, radial gradients, and spiral structure of the…
The solar system is moving through the partially ionized local interstellar cloud (LIC). The ionized matter of the LIC interacts with the expanding solar wind forming the heliospheric interface. The neutral component (interstellar atoms)…
We report the results of initial FUSE observations of molecular hydrogen (H2) in translucent clouds. These clouds have greater optical depth than any of the diffuse clouds previously observed for far-UV H2 absorption, and provide new…
We present Far Ultraviolet Spectroscopic Explorer (FUSE) observations of interstellar molecular hydrogen (H_2) in two Galactic high-velocity clouds (HVCs). Molecular hydrogen absorption is detected in the Magellanic Stream (abundance ~0.3…