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Related papers: Revised rate coefficients for H$_2$ and H$^-$ dest…

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We use one-dimensional radiative transfer simulations to study the evolution of H_2 gas-phase (H^- catalyzed) formation and photo-dissociation regions in the primordial universe. We find a new positive feedback mechanism capable of…

Astrophysics · Physics 2009-10-31 Massimo Ricotti , Nickolay Y. Gnedin , J. Michael Shull

During the epoch of reionization, the formation of radiation sources is accompanied by the growth of a H- photodissociating flux. We estimate the impact of this flux on the formation of molecular hydrogen and cooling in the first galaxies,…

Astrophysics · Physics 2009-11-13 Leonid Chuzhoy , Michael Kuhlen , Paul R. Shapiro

The ability of primordial gas to cool in proto-galactic haloes exposed to Lyman-Werner (LW) radiation is critically dependent on the self-shielding of H_2. We perform radiative transfer calculations of LW line photons, post-processing…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Jemma Wolcott-Green , Zoltán Haiman , Greg L. Bryan

Non-thermal photons deriving from radiative transitions among the internal ladder of atoms and molecules are an important source of photons in addition to thermal and stellar sources in many astrophysical environments. In the present work…

Astrophysics of Galaxies · Physics 2017-08-02 C. M. Coppola , M. V. Kazandjian , D. Galli , A. N. Heays , E. F. van Dishoeck

In the interstellar medium, cosmic rays (CRs) generate a field of ultraviolet (UV) photons via the excitation and subsequent radiative decay of $\rm H_2$ molecules. This UV field is a major agent of ionization and dissociation in the inner…

Astrophysics of Galaxies · Physics 2026-01-15 O. Sipilä , P. Caselli , M. Padovani , D. Galli , T. Grassi , H. R. Hrodmarsson , S. S. Jensen , E. Roueff

Tabulated rates for astrophysical photodisintegration reactions make use of Boltzmann statistics for the photons involved as well as the interacting nuclei. Here we derive analytic corrections for the Planck-spectrum quantum statistics of…

Solar and Stellar Astrophysics · Physics 2015-05-20 G. J. Mathews , Yamac Pehlivan , Toshitaka Kajino , A. B. Balantekin , Motohiko Kusakabe

A spectrophotometric model able to compute the integrated spectrum of a galaxy, including the contribution both of the stellar populations and of the ionized interstellar gas of the HII regions powered by young hot stars, has been used to…

Astrophysics · Physics 2009-08-17 G. Barbaro , B. M. Poggianti

We present new H$\alpha$ photometry for the Star-Formation Reference Survey (SFRS), a representative sample of star-forming galaxies in the local Universe. Combining these data with the panchromatic coverage of the SFRS, we provide…

The cosmological recombination of H and He at z \sim 1000 and the formation of H2 during the dark ages produce a non-thermal photon excess in the Wien tail of the cosmic microwave background (CMB) blackbody spectrum. Here we compute the…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-17 Carla Maria Coppola , Daniele Galli , Francesco Palla , Savino Longo , Jens Chluba

We consider collisional excitation of H$_2$ molecules in C-type shocks propagating in dense molecular clouds. New data on collisional rate coefficients for (de-)excitation of H$_2$ molecule in collisions with H atoms and new H$_2$…

Astrophysics of Galaxies · Physics 2019-09-18 A. V. Nesterenok , D. Bossion , Y. Scribano , F. Lique

The calibrations linking observed luminosities to the star formation rate depend on the assumed stellar population synthesis model, initial mass function, star formation and metal enrichment history, and whether reprocessing by dust and gas…

Astrophysics of Galaxies · Physics 2019-10-23 Stephen M. Wilkins , Christopher C. Lovell , Elizabeth R. Stanway

We study the connection of star formation to atomic (HI) and molecular hydrogen (H$_2$) in isolated, low metallicity dwarf galaxies with high-resolution ($m_{\rm gas}$ = 4 M$_\odot$, $N_{\rm ngb}$ = 100) SPH simulations. The model includes…

Astrophysics of Galaxies · Physics 2016-03-23 Chia-Yu Hu , Thorsten Naab , Stefanie Walch , Simon C. O. Glover , Paul C. Clark

Interstellar reddening corrections are necessary to reconstruct the intrinsic spectral energy distributions (SEDs) of accreting protostellar systems. The stellar SED determines the heating and chemical processes that can occur in…

A detailed modeling of simultaneous UV-photochemical and thermochemical processes in exoplanet atmosphere-like conditions is essential for the analysis and interpretation of a vast amount of current and future spectral data from exoplanets.…

Earth and Planetary Astrophysics · Physics 2023-04-26 Jeehyun Yang , Murthy S. Gudipati , Bryana L Henderson , Benjamin Fleury

Population III stars can regulate star formation in the primordial Universe in several ways. They can ionize nearby halos, and even if their ionizing photons are trapped by their own halos, their Lyman-Werner (LW) photons can still escape…

Astrophysics of Galaxies · Physics 2015-10-21 Anna T. P. Schauer , Daniel J. Whalen , Simon C. O. Glover , Ralf S. Klessen

The first, self-consistent calculations are presented of the cosmological, H2-dissociating UV background produced during the epoch of reionization by the sources of reionization. Large-scale radiative transfer simulations of reionization…

Astrophysics · Physics 2015-05-13 Kyungjin Ahn , Paul R. Shapiro , Ilian T. Iliev , Garrelt Mellema , Ue-Li Pen

We re-examine the effect of Lyman continuum ($\lambda \leq 912$ \AA) extinction (LCE) by dust in H {\sc ii} regions in detail and discuss how it affects the estimation of the global star formation rate (SFR) of galaxies. To clarify the…

Astrophysics · Physics 2009-11-06 Akio K. Inoue , Hiroyuki Hirashita , Hideyuki Kamaya

Galactic cosmic rays (CRs) play a crucial role in ionisation, dissociation, and excitation processes within dense cloud regions where UV radiation is absorbed by dust grains and gas species. CRs regulate the abundance of ions and radicals,…

Different wavelength regimes and methods for estimating the space density of the star-formation rate (SFR) result in discrepant values. While it is recognised that ultra-violet (UV) and H-alpha emission line data must be corrected for the…

Astrophysics · Physics 2009-11-06 A. M. Hopkins , A. J. Connolly , D. B. Haarsma , L. E. Cram

Cosmological models can be constrained by determining primordial abundances. Accurate predictions of the He I spectrum are needed to determine the primordial helium abundance to a precision of $< 1$% in order to constrain Big Bang…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-21 F. Guzmán , N. R. Badnell , R. J. R. Williams , P. A. M. van Hoof , M. Chatzikos , G. J. Ferland
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