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Physical Sciences and Mathematics Commons™

Open Access. Powered by Scholars. Published by Universities.®

Astrophysics and Astronomy

2011

ISM

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Structure And Feedback In 30 Doradus. Ii. Structure And Chemical Abundances, E. W. Pellegrini, J. A. Baldwin, Gary J. Ferland Aug 2011

Structure And Feedback In 30 Doradus. Ii. Structure And Chemical Abundances, E. W. Pellegrini, J. A. Baldwin, Gary J. Ferland

Physics and Astronomy Faculty Publications

We use our new optical-imaging and spectrophotometric survey of key diagnostic emission lines in 30 Doradus, together with CLOUDY photoionization models, to study the physical conditions and ionization mechanisms along over 4000 individual lines of sight at points spread across the face of the extended nebula, out to a projected radius 75 pc from R136 at the center of the ionizing cluster NGC 2070. We focus on the physical conditions, geometry, and importance of radiation pressure on a point-by-point basis, with the aim of setting observational constraints on important feedback processes. We find that the dynamics and large-scale structure of …

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A Survey Of Molecular Hydrogen In The Crab Nebula, E. D. Loh, J. A. Baldwin, Z. K. Curtis, Gary J. Ferland, C. R. O'Dell, A. C. Fabian, Philippe Salomé May 2011

A Survey Of Molecular Hydrogen In The Crab Nebula, E. D. Loh, J. A. Baldwin, Z. K. Curtis, Gary J. Ferland, C. R. O'Dell, A. C. Fabian, Philippe Salomé

Physics and Astronomy Faculty Publications

We have carried out a near-infrared, narrowband imaging survey of the Crab Nebula, in the H2 2.12 μm and Brγ 2.17 μm lines, using the Spartan Infrared camera on the SOAR Telescope. Over a 2.8 × 5'.1 area that encompasses about 2/3 of the full visible extent of the Crab, we detect 55 knots that emit strongly in the H2 line. We catalog the observed properties of these knots. We show that they are in or next to the filaments that are seen in optical-passband emission lines. Comparison to Hubble Space Telescope [S …

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Discovery Of Tev Gamma Ray Emission From Tycho's Supernova Remnant, P. T. Reynolds, Et Al Mar 2011

Discovery Of Tev Gamma Ray Emission From Tycho's Supernova Remnant, P. T. Reynolds, Et Al

Physical Sciences Publications

We report the discovery of TeV gamma-ray emission from the Type Ia supernova remnant (SNR) G120.1+1.4, known as Tycho's SNR. Observations performed in the period 2008-2010 with the VERITAS ground-based gamma-ray observatory reveal weak emission coming from the direction of the remnant, compatible with a point source located at 00h25m270, + 64°10'50'' (J2000). The TeV photon spectrum measured by VERITAS can be described with a power law dN/dE = C(E/3.42 TeV)–Γ with Γ = 1.95 ± 0.51stat ± 0.30sys and C = (1.55 ± 0.43stat ± 0.47sys) × 10–14 cm–2 s–1 TeV–1. The integral …

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The Redshift Search Receiver 3 Mm Wavelength Spectra Of 10 Galaxies, Ronald L. Snell, Gopal Narayanan, Min S. Yun, Mark Heyer, Aeree Chung, William M. Irvine, Neal R. Erickson, Guilin Liu Jan 2011

The Redshift Search Receiver 3 Mm Wavelength Spectra Of 10 Galaxies, Ronald L. Snell, Gopal Narayanan, Min S. Yun, Mark Heyer, Aeree Chung, William M. Irvine, Neal R. Erickson, Guilin Liu

Gopal Narayanan

The 3 mm wavelength spectra of 10 galaxies have been obtained at the Five College Radio Astronomy Observatory using a new, very broadband receiver and spectrometer, called the Redshift Search Receiver (RSR). The RSR has an instantaneous bandwidth of 37 GHz covering frequencies from 74 to 111 GHz and has a spectral resolution of 31 MHz (~100 km s–1). During tests of the RSR on the FCRAO 14 m telescope the complete 3 mm spectra of the central regions of NGC 253, Maffei 2, NGC1068, IC 342, M82, NGC 3079, NGC 3690, NGC 4258, Arp 220, and NGC 6240 were …

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Grb 091127: The Cooling Break Race On Magnetic Fuel, R. Filgas, J. Greiner, P. Schady, T. Krühler, Adria Updike, S. Klose, M. Nardini, D.A. Kann, A. Rossi, V. Sudilovsky, P.M.J. Afonso, C. Clemens, J. Elliott, A. Nicuesa Guelbenzu, F. Olivares E., A. Rau Jan 2011

Grb 091127: The Cooling Break Race On Magnetic Fuel, R. Filgas, J. Greiner, P. Schady, T. Krühler, Adria Updike, S. Klose, M. Nardini, D.A. Kann, A. Rossi, V. Sudilovsky, P.M.J. Afonso, C. Clemens, J. Elliott, A. Nicuesa Guelbenzu, F. Olivares E., A. Rau

Arts & Sciences Faculty Publications

No abstract provided.

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