Related papers: Irradiated ISM: Discriminating between Cosmic Rays…
To investigate the role of active galactic nucleus (AGN) X-ray irradiation on the interstellar medium (ISM), we systematically analyzed Chandra and ALMA CO($J$=2-1) data for 26 ultra-hard X-ray ($>$ 10 keV) selected AGNs at redshifts below…
A mid-infrared (3.6-8 um) survey of the Galactic Center has been carried out with the IRAC instrument on the Spitzer Space Telescope. This survey covers the central 2x1.4 degree (~280x200 pc) of the Galaxy. At 3.6 and 4.5 um the emission is…
We present results on the interstellar medium (ISM) properties of 29 galaxies based on a comparison of {\it Spitzer} far-infrared and Westerbork Synthesis Radio Telescope radio continuum imagery. Of these 29 galaxies, 18 are close enough to…
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.…
While the best tracer of the molecular component and its dynamics in galaxies is the CO molecule, which excitation is revealed by its isotopic and (2-1)/(1-0) ratios, the denser gas is revealed by molecules such as HCN, HNC, HCO+ or CN,…
The radiation from stars and active galactic nuclei (AGN) creates photodissociation regions (PDRs) and X-ray dominated regions (XDRs), where the chemistry or heating are dominated by far-ultraviolet (FUV) radiation or X-ray radiation,…
It has often been suggested that an alternative to the standard CO/21-cm method for estimating the mass of the interstellar medium (ISM) in a galaxy might be to estimate the mass of the ISM from the continuum dust emission. In this paper,…
The sensitive infrared telescopes, Spitzer and Herschel, have been used to target low-metallicity star-forming galaxies, allowing us to investigate the properties of their interstellar medium (ISM) in unprecedented detail. Interpretation of…
We have used archival far-ultraviolet spectra from observations made by HST/STIS and FUSE to determine the column densities and rotational excitation temperatures for CO and H2, respectively, along the lines of sight to 23 Galactic O and B…
Understanding the nature of high-$z$ dusty galaxies requires a comprehensive view of their ISM and molecular complexity. However, the molecular ISM at high-$z$ is commonly studied using only a few species beyond CO, limiting our…
An extinction-free estimator of the star-formation rate (SFR) of galaxies is critical for understanding the high-redshift universe. To this end, the nearly linear, tight correlation of far-infrared (FIR) and radio luminosity of star-forming…
Direct measurements of cosmic ray (CR) species combined with observations of their associated gamma-ray emissions can be used to constrain models of CR propagation, trace the structure of the Galaxy, and search for signatures of new…
The expansion of Galactic HII regions can trigger the formation of a new generation of stars. However, little is know about the physical conditions that prevail in these regions. We study the physical conditions that prevail in specific…
In the redshift interval of $2<z<3$, the physical conditions of the inter-stellar medium (ISM) in star-forming galaxies are likely to be different from those in the local Universe because of lower gaseous metallicities, higher gas…
We present a $^{13}\mathrm{CO} (J = 1 \rightarrow 0)$ mapping survey of 12 nearby galaxies from the CARMA STING sample. The line intensity ratio $\mathcal{R} \equiv I[^{12}\mathrm{CO} (J = 1 \rightarrow 0)]/I[^{13}\mathrm{CO} (J = 1…
The Herschel Dwarf Galaxy Survey investigates the interplay of star formation activity and the the metal-poor gas and dust of dwarf galaxies using FIR and submillimetre imaging spectroscopic and photometric observations in the 50 to 550mu…
We report an analysis of the interstellar $\gamma$-ray emission in the third Galactic quadrant measured by the {Fermi} Large Area Telescope. The window encompassing the Galactic plane from longitude $210\arcdeg$ to $250\arcdeg$ has…
(Abridged) Resolved observations of the CO emission from $z=1-3$ star-forming galaxies are becoming increasingly common, with new high-resolution surveys on the horizon. We aim to inform the interpretation of this resolved CO emission by…
The observed molecular properties of a sample of FIR-luminous and OH megamaser (OH-MM) galaxies have been investigated. The ratio of high and low-density tracer lines is found to be determined by the progression of the star formation in the…
The chemical properties of protoplanetary disks are especially sensitive to their ionization environment. Sources of molecular gas ionization include cosmic rays, stellar X-rays and short-lived radionuclides, each of which varies with…