Search Publications
The molecular universe
Tielens, A. G. G. M.
Molecular absorption and emission bands dominate the visible, infrared, and submillimeter spectra of most objects with associated gas. These observations reveal a surprisingly rich array of molecular species and attest to a complex chemistry taking place in the harsh environment of the interstellar medium of galaxies. Molecules are truly everywher…
The CO-to-H2 Conversion Factor and Dust-to-gas Ratio on Kiloparsec Scales in Nearby Galaxies
Roussel, H.; Armus, L.; Hunt, L. K. +42 more
We present ~kiloparsec spatial resolution maps of the CO-to-H2 conversion factor (αCO) and dust-to-gas ratio (DGR) in 26 nearby, star-forming galaxies. We have simultaneously solved for αCO and the DGR by assuming that the DGR is approximately constant on kiloparsec scales. With this assumption, we can combine maps…
A dust-obscured massive maximum-starburst galaxy at a redshift of 6.34
Thomson, A. P.; Altieri, B.; Pérez-Fournon, I. +61 more
Massive present-day early-type (elliptical and lenticular) galaxies probably gained the bulk of their stellar mass and heavy elements through intense, dust-enshrouded starbursts--that is, increased rates of star formation--in the most massive dark-matter haloes at early epochs. However, it remains unknown how soon after the Big Bang massive starbu…
Herschel view of the Taurus B211/3 filament and striations: evidence of filamentary growth?
Martin, P. G.; Hill, T.; White, G. L. +24 more
We present first results from the Herschel Gould Belt survey for the B211/L1495 region in the Taurus molecular cloud. Thanks to their high sensitivity and dynamic range, the Herschel images reveal the structure of the dense, star-forming filament B211 with unprecedented detail, along with the presence of striations perpendicular to the filament an…
The Herschel PEP/HerMES luminosity function - I. Probing the evolution of PACS selected Galaxies to z ≃ 4
Berta, S.; Magnelli, B.; Nordon, R. +100 more
We exploit the deep and extended far-IR data sets (at 70, 100 and 160 µm) of the Herschel Guaranteed Time Observation (GTO) PACS Evolutionary Probe (PEP) Survey, in combination with the Herschel Multi-tiered Extragalactic Survey data at 250, 350 and 500 µm, to derive the evolution of the rest-frame 35-, 60-, 90- and total infrared (IR)…
The deepest Herschel-PACS far-infrared survey: number counts and infrared luminosity functions from combined PEP/GOODS-H observations
Berta, S.; Magnelli, B.; Nordon, R. +34 more
We present results from the deepest Herschel-Photodetector Array Camera and Spectrometer (PACS) far-infrared blank field extragalactic survey, obtained by combining observations of the Great Observatories Origins Deep Survey (GOODS) fields from the PACS Evolutionary Probe (PEP) and GOODS-Herschel key programmes. We describe data reduction and thec…
Dusty starburst galaxies in the early Universe as revealed by gravitational lensing
Sharon, K.; Gladders, M. D.; Menten, K. M. +67 more
In the past decade, our understanding of galaxy evolution has been revolutionized by the discovery that luminous, dusty starburst galaxies were 1,000 times more abundant in the early Universe than at present. It has, however, been difficult to measure the complete redshift distribution of these objects, especially at the highest redshifts (z > …
Fast Molecular Outflows in Luminous Galaxy Mergers: Evidence for Quasar Feedback from Herschel
Lutz, D.; Genzel, R.; Maiolino, R. +18 more
We report the results from a systematic search for molecular (OH 119 µm) outflows with Herschel/PACS in a sample of 43 nearby (z < 0.3) galaxy mergers, mostly ultraluminous infrared galaxies (ULIRGs) and QSOs. We find that the character of the OH feature (strength of the absorption relative to the emission) correlates with that of the 9.7…
Global collapse of molecular clouds as a formation mechanism for the most massive stars
Avison, A.; André, Ph.; Schneider, N. +8 more
The relative importance of primordial molecular cloud fragmentation versus large-scale accretion still remains to be assessed in the context of massive core/star formation. Studying the kinematics of the dense gas surrounding massive-star progenitors can tell us the extent to which large-scale flow of material impacts the growth in mass of star-fo…
An old disk still capable of forming a planetary system
Zhang, Ke; Gorti, Uma; Henning, Thomas +11 more
From the masses of the planets orbiting the Sun, and the abundance of elements relative to hydrogen, it is estimated that when the Solar System formed, the circumstellar disk must have had a minimum mass of around 0.01 solar masses within about 100 astronomical units of the star. (One astronomical unit is the Earth-Sun distance.) The main constitu…