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Related papers: The cooling function of HD molecule revisited

200 papers

We investigated the cooling mechanism due to H2 and HD molecules in order to determine the minimum temperature achievable by cold H2-HD clouds in cooling flow clusters.

Astrophysics · Physics 2007-05-23 L. Grenacher , Ph. Jetzer , D. Puy

To model the temperature evolution of optically thin astrophysical environments at MHD scales, radiative and collisional cooling rates are typically either pre-tabulated or fit into a functional form and then input into MHD codes as a…

Solar and Stellar Astrophysics · Physics 2025-08-14 Amanda Stricklan , Tim Waters , James Klimchuk

Radiative processes play a pivotal role in shaping the thermal and chemical states of gas across diverse astrophysical environments, from the interstellar medium (ISM) to the intergalactic medium. We present a hybrid cooling model for…

We study the possibility that a large fraction of the gas at temperatures of \~10^7 K in cooling flow clusters cools by heat conduction to lower temperatures, rather than by radiative cooling. We argue that this process, when incorporated…

Astrophysics · Physics 2009-11-10 Noam Soker , Elizabeth L. Blanton , Craig L. Sarazin

We present a rigorous study of vibrational relaxation in p-H2 + p-H2 collisions at cold and ultracold temperatures and identify an efficient mechanism of ro-vibrational energy transfer. If the colliding molecules are in different rotational…

Quantum Physics · Physics 2008-04-02 Goulven Quéméner , Naduvalath Balakrishnan , Roman V. Krems

Based on measurements with the Effelsberg 100-m telescope, a multi-line study of molecular species is presented toward the gravitational lens system PKS1830-211. Obtaining average radial velocities and performing Large Velocity Gradient…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 C. Henkel , K. M. Menten , M. T. Murphy , N. Jethava , V. V. Flambaum , J. A. Braatz , S. Muller , J. Ott , R. Q. Mao

Collisional (de-)excitation of H$_{2}$ by helium plays an important role in the thermal balance and chemistry of various astrophysical environments, making accurate rate coefficients essential for the interpretation of observations of the…

Astrophysics of Galaxies · Physics 2024-05-15 Hubert Jóźwiak , Franck Thibault , Alexandra Viel , Piotr Wcisło , François Lique

We model a one-dimensional shock-tube using smoothed particle hydrodynamics and investigate the consequences of having finite shock-width in numerical simulations. We investigate the cooling of gas during passage through the shock for…

Astrophysics · Physics 2009-10-31 Roger M. Hutchings , Peter A. Thomas

We study the properties of gas inside and around galaxy haloes as a function of radius and halo mass, focussing mostly on z=2, but also showing some results for z=0. For this purpose, we use a suite of large cosmological, hydrodynamical…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Freeke van de Voort , Joop Schaye

Laser cycling of resonances can remove entropy from a system via spontaneously emitted photons, with electronic resonances providing the fastest cooling timescales because of their rapid relaxation rates. Although atoms are routinely laser…

Full-dimensional quantum scattering calculations are reported for ro-vibrational transitions in HD+HD collisions using a highly accurate interaction potential for the H$_2$-H$_2$ system. Several near-resonant ro-vibrational transitions are…

Atomic Physics · Physics 2026-03-06 Bikramaditya Mandal , Hubert Jóźwiak , Piotr Wcisło , Naduvalath Balakrishnan

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…

Astrophysics · Physics 2009-11-13 Thomas H. Greif , Jarrett L. Johnson , Ralf S. Klessen , Volker Bromm

We present the results of a series of calculations studying the collapse of molecular cloud cores performed using a three-dimensional smoothed particle hydr odynamics code with radiative transfer in the flux-limited diffusion approximation.…

Astrophysics · Physics 2009-11-13 Stuart C. Whitehouse , Matthew R. Bate

In several models of galaxy formation feedback occurs in cycles or mainly at high redshift. At times and in regions where feedback heating is ineffective, hot gas in the galaxy halo is expected to form a cooling flow, where the gas advects…

Astrophysics of Galaxies · Physics 2019-07-17 Jonathan Stern , Drummond Fielding , Claude-André Faucher-Giguère , Eliot Quataert

The gas temperature in the cores of many clusters of galaxies drops inward by about a factor of three or more within the central 100kpc radius. The radiative cooling time drops over the same region from 5 or more Gyr down to about 10^8 yr.…

Astrophysics · Physics 2009-11-07 A. C. Fabian

Dust and gas energetics are incorporated into a cluster-scale simulation of star formation in order to study the effect of heating and cooling on the star formation process. We build on our previous work by calculating separately the dust…

Solar and Stellar Astrophysics · Physics 2015-06-05 Hugo Martel , Andrea Urban , Neal J. Evans

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…

Astrophysics · Physics 2009-10-31 James G. Ingalls , T. M. Bania , Adair P. Lane , Matthias Rumitz , Antony A. Stark

A common situation in galactic and intergalactic gas involves cold dense gas in motion relative to hot diffuse gas. Kelvin-Helmholtz instability creates a turbulent mixing layer and populates the intermediate-temperature phase, which often…

Astrophysics of Galaxies · Physics 2020-05-20 Drummond B. Fielding , Eve C. Ostriker , Greg L. Bryan , Adam S. Jermyn

We model gas cooling in high-resolution N-body simulations in order to investigate the formation of the first generation of stars. We follow a region of a LCDM universe especially selected to contain a rich cluster by the present day. The…

$Q_{\rm int}$($T$), of the H$_2$$^{16}$O molecule is reported for temperatures between 0 and 6000 K. Determination of $Q_{\rm int}$($T$) is principally based on the direct summation technique involving all accurate experimental energy…