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Related papers: Metallicity effects in Photon Dominated Regions: C…

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Recent results are presented on the metal enrichment of low-mass star-forming (SF) galaxies in local Universe clusters. The environmental effects on the chemical evolution of these galaxies are discussed. We have used spectroscopic data…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-08 Vasiliki Petropoulou , Jose Manuel Vilchez , Jorje Iglesias-Paramo

We present a new selection of 358 blue compact dwarf galaxies (BCDs) from 5,000 square degrees in the Dark Energy Survey (DES), and the spectroscopic follow-up of a subsample of 68 objects. For the subsample of 34 objects with deep spectra,…

We are studying the effects of submm observations on the total dust mass and thus dust-to-gas mass ratio measurements. We gather a wide sample of galaxies that have been observed at submm wavelengths to model their Spectral Energy…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Maud Galametz , Suzanne C. Madden , Frederic Galliano , Sacha Hony , George J. Bendo , Marc Sauvage

We have calculated the radiation field, dust grain temperatures, and far infrared emissivity of numerical models of turbulent molecular clouds. When compared to a uniform cloud of the same mean optical depth, most of the volume inside the…

Astrophysics · Physics 2009-11-10 Thomas Bethell , Ellen Zweibel , Fabian Heitsch , J. S. Mathis

Observational studies have revealed that galaxy pairs tend to have lower gas-phase metallicity than isolated galaxies. This metallicity deficiency can be caused by inflows of low-metallicity gas due to the tidal forces and gravitational…

Astrophysics of Galaxies · Physics 2018-07-17 Sebastian Bustamante , Martin Sparre , Volker Springel , Robert J. J. Grand

Galaxy surveys have shown that luminous galaxies are mainly distributed in large filaments and galaxy clusters. The remaining large volumes are virtually devoid of luminous galaxies. This is in concordance with the formation of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Matthias Hoeft , Stefan Gottloeber

Star formation in galaxies is regulated by dynamical and thermal processes. The photoelectric effect on small dust grains usually dominates the heating of the star-forming neutral atomic gas reservoir in metal-rich galaxies, while the lower…

In this paper we discuss and confront recent results on metallicity variations in the local interstellar medium, obtained from observations of HII regions and neutral clouds of the Galactic thin disk, and compare them with recent…

Astrophysics of Galaxies · Physics 2022-06-08 C. Esteban , J. E. Méndez-Delgado , J. García-Rojas , K. Z. Arellano-Córdova

We present a study of emission lines of small hydrocarbons C$_2$H and $c$-C$_3$H$_2$, and COMs precursors H$_2$CO and CH$_3$OH in order to better understand the possible chemical link between the molecular abundances and UV radiation field…

Astrophysics of Galaxies · Physics 2021-08-25 Maria S. Kirsanova , Anna F. Punanova , Dmitry A. Semenov , Anton I. Vasyunin

In order to recognize environmental effects on the evolution of dwarf galaxies in clusters of galaxies, it is first necessary to quantify the properties of objects which have evolved in relative isolation. With oxygen abundance as the gauge…

The properties of substructure in galaxy clusters, exquisitely probed by gravitational lensing, offer a stringent test of dark matter (DM) models. Combining strong- and weak-lensing data for massive clusters, we map their total mass --…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-12 Priyamvada Natarajan , Barry T. Chiang , Isaque Dutra

Low-metallicity dwarf galaxies often show no or little CO emission, despite the intense star formation observed in local samples. Both simulations and resolved observations indicate that molecular gas in low-metallicity galaxies may reside…

The density of cosmic rays inside molecular clouds determines the ionization rate in the dense cores where stars form. It is also one of the drivers of astrochemistry leading to the creation of complex molecules. Through Fermi Large Area…

High Energy Astrophysical Phenomena · Physics 2023-01-18 Rui-zhi Yang , Guang-Xing Li , Emma de Oña Wilhelmi , Yu-Dong Cui , Bing Liu , Felix Aharonian

We revisit the reliability of metallicity estimates of high velocity clouds with the help of hydrodynamical simulations. We quantify the effect of accretion and viewing angle on metallicity estimates derived from absorption lines. Model…

Astrophysics of Galaxies · Physics 2021-11-24 F. Heitsch , A. Marchal , M. -A. Miville-Deschênes , J. M. Shull , A. J. Fox

Motivated by the presence of numerous dark matter clumps in the Milky Way's halo as expected from the cold dark matter cosmological model, we conduct numerical simulations to examine the heating of the disk. We construct an initial galaxy…

Astrophysics · Physics 2016-08-30 E. Ardi , T. Tsuchiya , A. Burkert

We derive the first luminosity-metallicity relation for a large objectively selected sample of local galaxy pairs and we compare the pairs LZ relation with the relation for the Nearby Field Galaxy Survey (NFGS). Galaxy pair members with…

Astrophysics · Physics 2008-11-26 L. J. Kewley , M. J. Geller , E. J. Barton

An overview is given of the chemical processes that occur in primordial systems under the influence of radiation, metal abundances and dust surface reactions. It is found that radiative feedback effects differ for UV and X-ray photons at…

Astrophysics · Physics 2009-11-13 M. Spaans

Hydrodynamic simulations of Lyman alpha clouds based on ab inito cosmological models have produced results that are in broad agreement with observations. However, further analyses have revealed that, with progressively higher numerical…

Astrophysics · Physics 2009-10-31 Renyue Cen , Greg L. Bryan

We present a study of the chemistry of a dense photon-dominated region (PDR) using a time-dependent chemical model. Our major interest is to study the spatial distribution of complex molecules such as hydrocarbons and cyanopolyynes in the…

Astrophysics · Physics 2009-11-13 O. Morata , E. Herbst

Due to their low gravitational energies, dwarf galaxies are greatly exposed to energetical influences from internal and external sources. By means of chemodynamical models we show that their star formation is inherently self-regulated, that…

Astrophysics · Physics 2009-11-11 S. Recchi , G. Hensler