3 results on '"Ted Bergin"'
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2. Next Generation Very Large Array Memo No. 6, Science Working Group 1: The Cradle of Life
- Author
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Andrea Isella, Charles L. H. Hull, Arielle Moullet, Roberto Galván-Madrid, Doug Johnstone, Luca Ricci, John Tobin, Leonardo Testi, BELTRAN SOROLLA, MARIA TERESA, Joseph Lazio, Andrew Siemion, Hauyu Baobab Liu, Fujun Du, Karin I. Öberg, Ted Bergin, Paola Caselli, Tyler Bourke, Chris Carilli, Laura Perez, Bryan Butler, Imke de Pater, Chunhua Qi, Mark Hofstadter, Raphael Moreno, David Alexander, Jonathan Williams, Paul Goldsmith, Mark Wyatt, Laurent Loinard, James Di Francesco, David Wilner, Peter Schilke, Adam Ginsburg, Álvaro Sánchez-Monge, Qizhou Zhang, and Henrik Beuther
- Subjects
Astrophysics::Earth and Planetary Astrophysics ,Astrophysics::Galaxy Astrophysics - Abstract
This is a white paper for project ngVLA This paper discusses compelling science cases for a future long-baseline interferometer operating at millimeter and centimeter wavelengths, like the proposed Next Generation Vary Large Array (ngVLA). We report on the activities of the Cradle of Life science working group, which focused on the formation of low- and high-mass stars, the formation of planets and evolution of protoplanetary disks, the physical and compositional study of Solar System bodies, and the possible detection of radio signals from extraterrestrial civilizations. We propose 19 scientific projects based on the current specification of the ngVLA. Five of them are highlighted as possible Key Science Projects: (1) Resolving the density structure and dynamics of the youngest HII regions and high-mass protostellar jets, (2) Unveiling binary/multiple protostars at higher resolution, (3) Mapping planet formation regions in nearby disks on scales down to 1 AU, (4) Studying the formation of complex molecules, and (5) Deep atmospheric mapping of giant planets in the Solar System. For each of these projects, we discuss the scientific importance and feasibility. The results presented here should be considered as the beginning of a more in-depth analysis of the science enabled by such a facility, and are by no means complete or exhaustive.
- Published
- 2015
3. Spatially extended OH + emission from the Orion Bar and Ridge
- Author
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Volker Ossenkopf, Z. Makai, Zsofia Nagy, Ted Bergin, Maryvonne Gerin, A. Faure, Floris van der Tak, John H. Black, SRON Netherlands Institute for Space Research (SRON), Laboratoire Univers et Théories (LUTH (UMR_8102)), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), West Virginia University [Morgantown], Institut de Planétologie et d'Astrophysique de Grenoble (IPAG ), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique (LERMA), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université de Cergy Pontoise (UCP), Université Paris-Seine-Université Paris-Seine-Centre National de la Recherche Scientifique (CNRS), Department of Astronomy [Ann Arbor], University of Michigan [Ann Arbor], University of Michigan System-University of Michigan System, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7), École normale supérieure - Paris (ENS Paris), and Astronomy
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Electron density ,Hydrogen ,Analytical chemistry ,FOS: Physical sciences ,chemistry.chemical_element ,Astrophysics ,01 natural sciences ,7. Clean energy ,Spectral line ,0103 physical sciences ,Radiative transfer ,010306 general physics ,010303 astronomy & astrophysics ,Astrophysics::Galaxy Astrophysics ,ComputingMilieux_MISCELLANEOUS ,Line (formation) ,Physics ,[PHYS]Physics [physics] ,astrochemistry ,Photodissociation ,Astronomy and Astrophysics ,Astrophysics - Astrophysics of Galaxies ,ISM: molecules ,chemistry ,13. Climate action ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,[PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] ,Excitation ,Bar (unit) - Abstract
We report the first detection of a Galactic source of OH+ line emission: the Orion Bar, a bright nearby photon-dominated region. Line emission is detected over ~1' (0.12 pc), tracing the Bar itself as well as the Southern tip of the Orion Ridge. The line width of ~4 km/s suggests an origin of the OH+ emission close to the PDR surface, at a depth of A_V ~0.3-0.5 into the cloud where most hydrogen is in atomic form. Steady-state collisional and radiative excitation models require unrealistically high OH+ column densities to match the observed line intensity, indicating that the formation of OH+ in the Bar is rapid enough to influence its excitation. Our best-fit OH+ column density of ~1x10^14 cm^-2 is similar to that in previous absorption line studies, while our limits on the ratios of OH+/H2O+ (>~40) and OH+/H3O+ (>~15) are higher than seen before. The column density of OH+ is consistent with estimates from a thermo-chemical model for parameters applicable to the Orion Bar, given the current uncertainties in the local gas pressure and the spectral shape of the ionizing radiation field. The unusually high OH+/H2O+ and OH+/H3O+ ratios are probably due to the high UV radiation field and electron density in this object. In the Bar, photodissociation and electron recombination are more effective destroyers of OH+ than the reaction with H2, which limits the production of H2O+. The appearance of the OH+ lines in emission is the result of the high density of electrons and H atoms in the Orion Bar, since for these species, inelastic collisions with OH+ are faster than reactive ones. In addition, chemical pumping, far-infrared pumping by local dust, and near-UV pumping by Trapezium starlight contribute to the OH+ excitation. Similar conditions may apply to extragalactic nuclei where OH+ lines are seen in emission., Accepted by A&A; 10 pages, 5 figures
- Published
- 2013
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