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Related papers: Benchmarking PDR models against the Horsehead edge

200 papers

We analyze $^{12}$CO($J$=2-1), $^{13}$CO($J$=2-1), C$^{18}$O ($J$=2-1), and 1.3 mm continuum maps of the $\rho$ Ophiuchi A photo-dissociation region (PDR) obtained with ALMA. Layered structures of the three CO isotopologues with an angular…

Astrophysics of Galaxies · Physics 2019-04-24 M. Yamagishi , C. Hara , R. Kawabe , F. Nakamura , T. Kamazaki , T. Takekoshi , Y. Shimajiri , H. Nomura , S. Takakuwa , J. Di Francesco

The HH 1/2 system has been observed with the two spectrometers on board the Infrared Space Observatory. Diffuse [CII] 158um emission indicate the presence of a Photo-Dissociation Region (PDR) which is only in part due to the external Far-UV…

Astrophysics · Physics 2009-11-07 Sergio Molinari , Alberto Noriega-Crespo

To test the PDR model spectra under the physical conditions present in Orion, we have obtained moderate-resolution (R=3000) J-, H-, and K-band long-slit spectra of the Orion bar and Orion S regions These observations provide conclusive…

Astrophysics · Physics 2009-10-30 K. L. Luhman , C. W. Engelbracht , M. L. Luhman

The mid-infrared (MIR) spectra of dense photodissociation regions (PDRs) are typically dominated by emission from polycyclic aromatic hydrocarbons (PAHs) and the lowest pure rotational states of molecular hydrogen (H2); two species which…

Astrophysics of Galaxies · Physics 2011-02-09 Brian T. Fleming , Kevin France , Roxana E. Lupu , Stephan R. McCandliss

Chemistry plays an important role in the interstellar medium (ISM), regulating heating and cooling of the gas, and determining abundances of molecular species that trace gas properties in observations. Although solving the time-dependent…

Astrophysics of Galaxies · Physics 2019-04-05 Munan Gong , Eve C. Ostriker , Mark G. Wolfire

We present 3.65''x3.34'' angular-resolution IRAM PdBI observations of the CS J=2-1 line toward the Horsehead Photodissociation Region (PDR), complemented with IRAM-30m single-dish observations of several rotational lines of CS, C34S and…

Astrophysics · Physics 2009-11-11 J. R. Goicoechea , J. Pety , M. Gerin , D. Teyssier , E. Roueff , P. Hily-Blant , S. Baek

We present spectroscopic observations obtained with the infrared Spitzer Space Telescope, which provide insight into the H$_2$ physics and gas energetics in photodissociation Regions (PDRs) of low to moderate far-ultraviolet (FUV) fields…

High-resolution ALMA images towards the Orion Bar show no discernible offset between the peak of H2 emission in the photodissociation region (PDR) and the CO(3-2) and HCO+(4-3) emission in the molecular region. This implies that positions…

Astrophysics of Galaxies · Physics 2019-04-17 Maria S. Kirsanova , Dmitri S. Wiebe

With the advent of wide-area submillimeter surveys, a large number of high-redshift gravitationally lensed dusty star-forming galaxies (DSFGs) has been revealed. Due to the simplicity of the selection criteria for candidate lensed sources…

We propose a methodology for intercomparing climate models and evaluating their performance against benchmarks based on the use of the Wasserstein distance (WD). This distance provides a rigorous way to measure quantitatively the difference…

Atmospheric and Oceanic Physics · Physics 2020-11-16 Gabriele Vissio , Valerio Lembo , Valerio Lucarini , Michael Ghil

Photodissociation regions (PDRs) are parts of the ISM consisting of predominantly neutral gas, located at the interface between H II regions and molecular clouds. The physical conditions within these regions show variations on very short…

Context. The combined use of carbon radio recombination lines (CRRLs) and the 158 $\mu$m-[CII] line is a powerful tool for the study of the energetics and physical conditions (e.g., temperature and density) of photodissociation regions…

Astrophysics of Galaxies · Physics 2019-05-09 P. Salas , J. B. R. Oonk , K. L. Emig , C. Pabst , M. C. Toribio , H. J. A. Röttgering , A. G. G. M. Tielens

Our understanding of physical processes in Photodissociation regions or Photon Dominated Regions (PDRs) largely depends on the ability of spectral synthesis codes to reproduce the observed infrared emission-line spectrum. In this paper, we…

Astrophysics · Physics 2009-11-13 N. P. Abel , P. A. M. van Hoof , G. Shaw , G. J. Ferland , T. Elwert

We present 101 and 151 GHz ALMA continuum images for 85 fields selected from Herschel observations that have 500 micron flux densities >80 mJy and 250-500 micron colours consistent with z > 2, most of which are expected to be…

The James Webb Space Telescope enabled the first detection of several rovibrational emission lines of HD in the Orion Bar, a prototypical photodissociation region. This provides an incentive to examine the physics of HD in dense and strong…

We derive total (atomic + molecular) hydrogen densities in giant molecular clouds (GMCs) in the nearby spiral galaxy M33 using a method that views the atomic hydrogen near regions of recent star formation as the product of…

Astrophysics of Galaxies · Physics 2015-05-27 J. S. Heiner , R. J. Allen , P. C. van der Kruit

Mid-infrared (IR) observations of polycyclic aromatic hydrocarbons (PAHs) and molecular hydrogen emission are a potentially powerful tool to derive physical properties of dense environments irradiated by intense UV fields. We present new,…

Astrophysics of Galaxies · Physics 2014-11-20 O. Berne , A. Fuente , J. R. Goicoechea , P. Pilleri , M. Gonzalez-Garcia , C. Joblin

This paper provides an overview of the spectroscopic data obtained by the JWST Guaranteed Time Observations (GTO) program 1192, "The Physics and Chemistry of PDR Fronts", including an inventory of the spatially resolved dust, gas, and…

Aims. We investigate the dominant formation mechanism of H2CO and CH3OH in the Horsehead PDR and its associated dense core. Methods. We performed deep integrations of several H2CO and CH3OH lines at two positions in the Horsehead, namely…

Astrophysics of Galaxies · Physics 2015-06-17 V. V. Guzman , J. R. Goicoechea , J. Pety , P. Gratier , M. Gerin , E. Roueff , F. Le Petit , J. Le Bourlot , A. Faure

One of the fundamental results used in observational cosmology is the distance duality relation (DDR), which relates the luminosity distance, $D_L$, with angular diameter distance, $D_A$, at a given redshift $z$. We employ the observed…

Cosmology and Nongalactic Astrophysics · Physics 2017-02-01 Prabhakar Tiwari