English
Related papers

Related papers: Formation Pumping of Molecular Hydrogen in Dark Cl…

200 papers

Spitzer space telescope observations led to the surprising detection of a diverse set of extragalactic sources whose infrared spectra are dominated by line emission of molecular hydrogen (H2). The absence or relative weakness of typical…

Astrophysics · Physics 2008-10-03 P. Guillard , F. Boulanger

We introduce a sub-grid model for the non-equilibrium abundance of molecular hydrogen in cosmological simulations of galaxy formation. We improve upon previous work by accounting for the unresolved structure of molecular clouds in a…

Astrophysics of Galaxies · Physics 2015-06-19 Matteo Tomassetti , Cristiano Porciani , Emilio Romano-Diaz , Aaron D. Ludlow

Molecular hydrogen has an important role in the early stages of star formation as well as in the production of many other molecules that have been detected in the interstellar medium. In this review we show that it is now possible to study…

Molecular hydrogen (H$_2$) formation and dissociation are key processes that drive the gas lifecycle in galaxies. Using the SImulating the LifeCycle of Molecular Clouds (SILCC) zoom-in simulation suite, we explore the utility of future…

Molecular outflows contributing to the matter cycle of star forming galaxies are now observed in small and large systems at low and high redshift. Their physical origin is still unclear. In most theoretical studies only warm ionised/neutral…

Astrophysics of Galaxies · Physics 2021-05-28 Philipp Girichidis , Thorsten Naab , Stefanie Walch , Thomas Berlok

We present new observations of near-infrared molecular hydrogen (H2) line emission in a sample of 18 Class I and flat-spectrum low mass protostars, primarily in the Tau- Aur and {\rho} Oph dark clouds. The line emission is extended by up to…

Solar and Stellar Astrophysics · Physics 2015-05-20 Thomas P. Greene , Mary Barsony , David A. Weintraub

We combine recent ISO observations of the vibrational ground state lines of H2 towards Photon-Dominated Regions (PDRs) with observations of vibrationally excited states made with ground-based telescopes in order to constrain the formation…

Astrophysics · Physics 2009-11-10 E. Habart , F. Boulanger , L. Verstraete , C. M. Walmsley , G. Pineau des Forets

Molecular hydrogen (H2) is the primary component of the reservoirs of cold, dense gas that fuel star formation in our galaxy. While the H2 abundance is ultimately regulated by physical processes operating on small scales in the interstellar…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Robert Feldmann , Jose Hernandez , Nickolay Y. Gnedin

We investigate the physical properties of molecular hydrogen (H2) in isolated and interacting disk galaxies with different masses and Hubble types by using chemodynamical simulations with H2 formation on dust grains and dust growth and…

Astrophysics of Galaxies · Physics 2017-03-08 Kenji Bekki

When a fast moving star or a protostellar jet hits an interstellar cloud, the surrounding gas gets heated and illuminated: a bow shock is born which delineates the wake of the impact. In such a process, the new molecules that are formed and…

Astrophysics of Galaxies · Physics 2017-11-27 L. N. Tram , P. Lesaffre , S. Cabrit , A. Gusdorf , P. T. Nhung

The study of the formation of molecular hydrogen on low temperature surfaces is of interest both because it allows to explore elementary steps in the heterogeneous catalysis of a simple molecule and because of the applications in…

Chemical Physics · Physics 2008-11-21 G. Vidali , V. Pirronello , L. Li , J. Roser , G. Manico , R. Mehl , A. Lederhendler , H. B. Perets , J. R. Brucato , O. Biham

We investigate the formation and evolution of interstellar dust-grain ices under dark-cloud conditions, with a particular emphasis on CO2. We use a three-phase model (gas/surface/mantle) to simulate the coupled gas--grain chemistry,…

Astrophysics of Galaxies · Physics 2015-05-28 Robin T. Garrod , Tyler Pauly

The formation of H2 and HD molecules on interstellar dust grains is studied using rate equation and master equation models. Rate equations are used in the analysis of laboratory experiments which examine the formation of molecular hydrogen…

Astrophysics · Physics 2007-07-11 Ofer Biham , Azi Lipshtat , Hagai B. Perets

We present new analytic theory and radiative transfer computations for the atomic to molecular (HI-to-H2) transitions, and the build-up of atomic-hydrogen (HI) gas columns, in optically thick interstellar clouds, irradiated by…

Astrophysics of Galaxies · Physics 2015-06-19 Amiel Sternberg , Franck Le Petit , Evelyne Roueff , Jacques Le Bourlot

We study the evolution of molecular hydrogen on the grain surfaces and in the gas phase using both the rate equation (which tracks the average number of molecules) and the master equation (which tracks the expectation values of molecules).…

Astrophysics · Physics 2009-11-10 K. Acharyya , Sandip K. Chakrabarti , S. Chakrabarti

We have developed an excitation model for small molecules including radiative pumping by dust photons from near infrared to submillimeter wavelengths. This model applies to molecules within bright photodissociation regions in galactic…

Astrophysics · Physics 2009-09-25 M. Giard , J. L. Puget , E. Crete , F. Scoupe

The mass of molecular gas in an interstellar cloud is often measured using line emission from low rotational levels of CO, which are sensitive to the CO mass, and then scaling to the assumed molecular hydrogen H_2 mass. However, a…

Astrophysics of Galaxies · Physics 2015-05-18 Mark G. Wolfire , David Hollenbach , Christopher F. McKee

We study the formation of molecular hydrogen on dust grain surfaces and apply our results to the high redshift universe. We find that a range of physical parameters, in particular dust temperature and gas temperature, but not so much dust…

Astrophysics · Physics 2016-08-30 S. Cazaux , M. Spaans

We report results from a FUSE survey of interstellar molecular hydrogen (H2) in the Galactic disk toward 139 O-type and early B-type stars at Galactic latitudes $|b| < 10^{\circ}$, with updated photometric and parallax distances. The H2…

Astrophysics of Galaxies · Physics 2021-04-21 J. Michael Shull , Charles W. Danforth , Katherine L. Anderson

Motivated by the observed connection between molecular hydrogen (H2) and star formation, we present a method for tracking the non-equilibrium abundance and cooling processes of H2 and H2-based star formation in Smoothed Particle…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Charlotte Christensen , Thomas Quinn , Fabio Governato , Adrienne Stilp , Sijing Shen , James Wadsley