Related papers: Is H3+ cooling ever important in primordial gas?
In the interstellar cold gas, the chemistry of formaldehyde (H$_2$CO) can be essential to explain the formation of complex organic molecules. On this matter, the massive and energetic protostellar object G331 is still unexplored and, hence,…
After the recombination of Hydrogen, primordial molecules such as H_2, $HD$ can be formed.The formation of structures in the post-recombination gaseous medium is commonly explained by primordial density fluctuations. In a self-gravitating…
Cooling and heating functions of cosmic gas are a crucial ingredient for any study of gas dynamics and thermodynamics in the interstellar and intergalactic medium. As such, they have been studied extensively in the past under the assumption…
We report new calculations of the cooling rate of primordial gas by the HD molecule, taking into account its ro-vibrational structure. The HD cooling function is calculated including radiative and collisional transitions for J\le8…
Using high resolution infrared spectroscopy we have surveyed twenty sightlines for H3+ absorption. H3+ is detected in eight diffuse cloud sightlines with column densities varying from 0.6x10^14 cm^-2 to 3.9x10^14 cm^-2. This brings to…
Using an absorption line from the metastable (J, K) = (3, 3) level of H3+ together with other lines of H3+ and CO observed along several sightlines, we have discovered a vast amount of high temperature (T ~ 250 K) and low density (n ~ 100…
The formation of the first stars out of metal-free gas appears to result in stars at least an order of magnitude more massive than in the present-day case. We here consider what controls the transition from a primordial to a modern initial…
Suppression of H2-cooling in early protogalaxies has important implications for the formation of supermassive black holes seeds, the first generation of stars, and the epoch of reionization. This suppression can occur via photodissociation…
Context. Molecular hydrogen and its cation H+2 are among the first species formed in the early Universe, and play a key role in the thermal and chemical evolution of the primordial gas. In molecular clouds, H+2 ions formed through…
Starburst galaxies are undergoing intense periods of star formation. Understanding the heating and cooling mechanisms in these galaxies can give us insight to the driving mechanisms that fuel the starburst. Molecular emission lines play a…
Observations of molecular clouds in metal-poor environments typically find that they have much higher star formation rates than one would expect based on their observed CO luminosities and the molecular gas masses that are inferred from…
The measured emission-weighted metal abundance of the hot gas in early-type galaxies has been known to be lower than theoretical expectations for 20 years. In addition, both X-ray luminosity and metal abundance vary significantly among…
Radiative cooling by metals in shocked gas mediates the formation of ionization front instabilities in the galaxy today that are responsible for a variety of phenomena in the interstellar medium, from the morphologies of nebulae to…
This work follows Lykins et al. discussion of classic plasma cooling function at low density and solar metallicity. Here we focus on how the cooling function changes over a wide range of density (n_H<10^12 cm^(-3)) and metallicity (Z<30Z…
During the accretion of Titan, impact heating may have been sufficient to allow the global melting of water ice and the release of volatile compounds, mainly constituted of CO2, CH4 and NH3. The duration and efficiency of exchange between…
We report the first interstellar identification of protonated acetylene, C2H3+, a fundamental hydrocarbon, in the z=0.89 molecular absorber toward the gravitationally lensed quasar PKS1830-211. The molecular species is identified from clear…
The freezeout of gas-phase species onto cold dust grains can drastically alter the chemistry and the heating-cooling balance of protostellar material. In contrast to well-known species such as carbon monoxide (CO), the freezeout of various…
New high-resolution dissociative recombination rate coefficients of rotationally cool and hot H3+ in the vibrational ground state have been measured with a 22-pole trap setup and a Penning ion source, respectively, at the ion storage ring…
We investigate the properties of the first galaxies at z > 10 with highly resolved numerical simulations, starting from cosmological initial conditions and taking into account all relevant primordial chemistry and cooling. A first galaxy is…
We study the thermal evolution of primordial star-forming gas clouds using three-dimensional cosmological simulations. We critically examine how assumptions and approximations made in calculating radiative cooling rates affect the dynamics…