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6,830 full-text articles. Page 211 of 212.

Evidence For Supernova-Synthesized Dust From The Rising Afterglow Of Grb071025 At Z ∼ 5, Daniel A. Perley, J. S. Bloom, C. R. Klein, S. Covino, T. Minezaki, P. Wo´zniak, W. T. Vestrand, G. G. Williams, P. Milne, N. R. Butler, Adria Updike, T. Kr¨uhler, P. Afonso, A. Antonelli, L. Cowie, P. Ferrero, J. Greiner, D. H. Hartmann, Y. Kakazu, A. K¨upc¨u Yoldas¸, A. N. Morgan, P. A. Price, J. X. Prochaska, Y. Yoshii 2010 Roger Williams University

Evidence For Supernova-Synthesized Dust From The Rising Afterglow Of Grb071025 At Z ∼ 5, Daniel A. Perley, J. S. Bloom, C. R. Klein, S. Covino, T. Minezaki, P. Wo´Zniak, W. T. Vestrand, G. G. Williams, P. Milne, N. R. Butler, Adria Updike, T. Kr¨Uhler, P. Afonso, A. Antonelli, L. Cowie, P. Ferrero, J. Greiner, D. H. Hartmann, Y. Kakazu, A. K¨Upc¨U Yoldas¸, A. N. Morgan, P. A. Price, J. X. Prochaska, Y. Yoshii

Arts & Sciences Faculty Publications

No abstract provided.


A Very Metal-Poor Damped Lyman-Α System Revealed Through The Most Energetic Grb 090926a, A. Rau, S. Savaglio, T. Kr¨ uhler, P. Afonso, J. Greiner, S. Klose, P. Schady, S. McBreen, R. Filgas, F. Olivares E., A. Rossi, Adria Updike 2010 Roger Williams University

A Very Metal-Poor Damped Lyman-Α System Revealed Through The Most Energetic Grb 090926a, A. Rau, S. Savaglio, T. Kr¨ Uhler, P. Afonso, J. Greiner, S. Klose, P. Schady, S. Mcbreen, R. Filgas, F. Olivares E., A. Rossi, Adria Updike

Arts & Sciences Faculty Publications

No abstract provided.


The Physical And Dynamical Structure Of Serpens - Two Very Different Sub-(Proto)Clusters, A. Duarte-Cabral, G. A. Fuller, N. Peretto, J. Hatchell, Edwin F. Ladd, J. Buckle, J. Richer, S. F. Graves 2010 Bucknell University

The Physical And Dynamical Structure Of Serpens - Two Very Different Sub-(Proto)Clusters, A. Duarte-Cabral, G. A. Fuller, N. Peretto, J. Hatchell, Edwin F. Ladd, J. Buckle, J. Richer, S. F. Graves

Faculty Journal Articles

No abstract provided.


The Afterglows Of Swift-Era Gamma-Ray Bursts. I. Comparing Pre-Swift And Swift-Era Long/Soft (Type Ii) Grb Optical Afterglows, D. A. Kann, S. Klose, B. Zhang, D. Malesani, E. Nakar, A. Pozanenko, A. C. Wilson, N. R. Butler, P. Jakobsson, S. Schulze, M. Andreev, L. A. Antonelli, I. F. Bikmaev, V. Biryukov, M. B¨ottcher, R. A. Burenin, J. M. Castro Cer´on, A. J. Castro-Tirado, G. Chincarini, B. E. Cobb, S. Covino, P. D’Avanzo, V. D’Elia, M. Della Valle, A. de Ugarte Postigo, Yu Efimov, P. Ferrero, D. Fugazza, D. Fugazza, J. P.U. Fynbo, M. Gålfalk, F. Grundahl, J. Gorosabel, S. Gupta, S. Guziy, B. Hafizov, J. Hjorth, K. Holhjem, M. Ibrahimov, M. Im, G. L. Israel, M. Je´linek, B. L. Jensen, R. Karimov, I. M. Khamitov, U. Kizilogˇlu, E. Klunko, P. Kuba´nek, A. S. Kutyrev, P. Laursen, A. J. Levan, F. Mannucci, C. M. Martin, A. Mescheryakov, N. Mirabal, J. P. Norris, J. -E. Ovaldsen, D. Paraficz, E. Pavlenko, S. Piranomonte, A. Rossi, V. Rumyantsev, R. Salinas, A. Sergeev, D. Sharapov, J. Sollerman, B. Stecklum, L. Stella, G. Tagliaferri, N. R. Tanvir, J. Telting, V. Testa, Adria Updike, A. Volnova, D. Watson, K. Wiersema, D. Xu 2010 Roger Williams University

The Afterglows Of Swift-Era Gamma-Ray Bursts. I. Comparing Pre-Swift And Swift-Era Long/Soft (Type Ii) Grb Optical Afterglows, D. A. Kann, S. Klose, B. Zhang, D. Malesani, E. Nakar, A. Pozanenko, A. C. Wilson, N. R. Butler, P. Jakobsson, S. Schulze, M. Andreev, L. A. Antonelli, I. F. Bikmaev, V. Biryukov, M. B¨Ottcher, R. A. Burenin, J. M. Castro Cer´On, A. J. Castro-Tirado, G. Chincarini, B. E. Cobb, S. Covino, P. D’Avanzo, V. D’Elia, M. Della Valle, A. De Ugarte Postigo, Yu Efimov, P. Ferrero, D. Fugazza, D. Fugazza, J. P.U. Fynbo, M. Gålfalk, F. Grundahl, J. Gorosabel, S. Gupta, S. Guziy, B. Hafizov, J. Hjorth, K. Holhjem, M. Ibrahimov, M. Im, G. L. Israel, M. Je´Linek, B. L. Jensen, R. Karimov, I. M. Khamitov, U. KizilogˇLu, E. Klunko, P. Kuba´Nek, A. S. Kutyrev, P. Laursen, A. J. Levan, F. Mannucci, C. M. Martin, A. Mescheryakov, N. Mirabal, J. P. Norris, J. -E. Ovaldsen, D. Paraficz, E. Pavlenko, S. Piranomonte, A. Rossi, V. Rumyantsev, R. Salinas, A. Sergeev, D. Sharapov, J. Sollerman, B. Stecklum, L. Stella, G. Tagliaferri, N. R. Tanvir, J. Telting, V. Testa, Adria Updike, A. Volnova, D. Watson, K. Wiersema, D. Xu

Arts & Sciences Faculty Publications

We have gathered optical photometry data from the literature on a large sample of Swift-era gamma-ray burst (GRB) afterglows including GRBs up to 2009 September, for a total of 76 GRBs, and present an additional three pre-Swift GRBs not included in an earlier sample. Furthermore, we publish 840 additional new photometry data points on a total of 42 GRB afterglows, including large data sets for GRBs 050319, 050408, 050802, 050820A, 050922C, 060418, 080413A, and 080810. We analyzed the light curves of all GRBs in the sample and derived spectral energy distributions for the sample with the best data quality, allowing ...


Sensitivity Of Planetary Boundary Layer To Varying Volumetric Soil Moisture: A Mesoscale Models Comparision, Asrid Suarez Gonzalez 2010 Western Kentucky U\

Sensitivity Of Planetary Boundary Layer To Varying Volumetric Soil Moisture: A Mesoscale Models Comparision, Asrid Suarez Gonzalez

Honors College Capstone Experience/Thesis Projects

A comparison between two Mesoscale models, Colorado State University Regional Atmospheric Model System (RAMS) version 4.4 coupled with the Land‐Ecosystem– Atmosphere Feedback Model (LEAF2) and Penn State/NCAR’s Mesoscale Model (MM5) coupled with NOAH Land Surface Model, was conducted in order to assess the sensitivity of forecasted boundary layer variables to anomalous volumetric soil moistures. The study elaborates on the findings of Quintanar et al. (2008) using the study’s experimental design as a template for our numerical model comparison. The experiments were conducted using the same synoptic events examined by Quintanar et al. (2008): June 11 ...


Begin The Adventure : How To Break The Light Barrier By A.D. 2079 (3rd Ed.), Florentin Smarandache, Homer B. Tilton 2010 University of New Mexico

Begin The Adventure : How To Break The Light Barrier By A.D. 2079 (3rd Ed.), Florentin Smarandache, Homer B. Tilton

Faculty and Staff Publications

This edition, the third, has undergone a subtle name change, going from "A.D. 2070" in the title to A.D. 2079 as the timeline is fine-tuned. Because of the almost universal failure to recognize the distinction between physical (reality-based, dynamical) and visual (appearance-based, kinematical) variables, a tremendous volume of mythology arose over the past 100 years centered around Einstein's reality view of the distortions of special relativity. To get a sense of it, we point the reader to Paul J. Nahin's heroic book, Time Machines, 2nd ed.,- to these Tech Notes in particular: TN#6. "A High-Speed ...


The Zeeman Effect In The Sobolev Approximation Ii. Radial Split Monopole Fields And The ‘Heartbeat’ Stokes V Profile., K. Gayley, Richard Ignace 2010 University of Iowa

The Zeeman Effect In The Sobolev Approximation Ii. Radial Split Monopole Fields And The ‘Heartbeat’ Stokes V Profile., K. Gayley, Richard Ignace

ETSU Faculty Works

We calculate the circularly polarized Stokes V(λ) profile for emission lines, formed in hot-star winds threaded with a weak radial magnetic field. For simplicity, the field is treated as a split monopole under the assumptions that it has been radially combed by the wind, and rotation is not playing a central role. Invoking the weak-field approximation, we find that the V(λ) profile has a characteristic “heartbeat” shape exhibiting multiple sign inversions, which might be mistaken for noise in the absence of theoretical guidance. We also conclude that there is a tendency for the V(λ) profile to integrate ...


Rotational Modulation, Shear, And Cyclic Activity In Hii 1883, Jacquelynne Brenda Milingo, S. H. Saar, Laurence A. Marschall, J. R. Stauffer 2010 Gettysburg College

Rotational Modulation, Shear, And Cyclic Activity In Hii 1883, Jacquelynne Brenda Milingo, S. H. Saar, Laurence A. Marschall, J. R. Stauffer

Physics and Astronomy Faculty Publications

We present a 30 year compilation of V-band differential photometry for the Pleiades K dwarf HII 1883. HII 1883 has an average rotational period (Pr ot) of ~ 0.235d and displays rotational modulation due to non-uniform surface brightness as large as 0.2 magnitudes in V.Preliminary work yields a cycle period of ∼ 9yrs and rotational shear oPr ot/(Pr ot) considerably less than solar. With such a long baseline of data available we can explore many aspects of the star’s photometric variability. We present studies of the variation of the rotational modulation amplitude, (V), and Pr ot over ...


Off To A Good Start: Using Clustering To Select The Initial Training Set In Active Learning, Rong Hu, Brian Mac Namee, Sarah Jane Delany 2010 Technological University Dublin

Off To A Good Start: Using Clustering To Select The Initial Training Set In Active Learning, Rong Hu, Brian Mac Namee, Sarah Jane Delany

Conference papers

Active learning (AL) is used in textual classification to alleviate the cost of labelling documents for training. An important issue in AL is the selection of a representative sample of documents to label for the initial training set that seeds the process, and clustering techniques have been successfully used in this regard. However, the clustering techniques used are nondeterministic which causes inconsistent behaviour in the AL process. In this paper we first illustrate the problems associated with using non-deterministic clustering for initial training set selection in AL. We then examine the performance of three deterministic clustering techniques for this task ...


Non-Linear Pair Production In Scattering Of Photons On Ultra-Short Laser Pulses At High Energy, Kirill Tuchin 2010 Iowa State University

Non-Linear Pair Production In Scattering Of Photons On Ultra-Short Laser Pulses At High Energy, Kirill Tuchin

Physics and Astronomy Publications

We consider scattering of a photon on a short intense laser pulse at high energy. We argue that for ultrashort laser pulses the interaction is coherent over the entire length of the pulse. At low pulse intensity I the total cross section for electron–positron pair production is proportional to I. However, at pulse intensities higher than the characteristic value Is , the total cross section saturates – it becomes proportional to the logarithm of intensity. This non-linear effect is due to multi-photon interactions. We derive the total cross section for pair production at high energies by resuming the multi-photon amplitudes to ...


A New Method For Describing The Horizontal Electric Field Induced By A Lightning Strike Return Stroke, S L. Meredith, S K. Earles, Niescja E. Turner 2010 Trinity University

A New Method For Describing The Horizontal Electric Field Induced By A Lightning Strike Return Stroke, S L. Meredith, S K. Earles, Niescja E. Turner

Physics and Astronomy Faculty Research

No abstract provided.


The Magnetic Field Induced By A Lightning Strikes Indirect Effect Double Exponential Current Waveform, S L. Meredith, S K. Earles, I N. Kostanic, Niescja E. Turner 2010 Trinity University

The Magnetic Field Induced By A Lightning Strikes Indirect Effect Double Exponential Current Waveform, S L. Meredith, S K. Earles, I N. Kostanic, Niescja E. Turner

Physics and Astronomy Faculty Research

Problem statement: Develop a new formula which describes the magnetic field induced by a lightning strike's indirect effect double exponential current waveform. Approach: A novel approach for developing a closed-form solution for the magnetic field from the indirect effect double exponential current waveform will be presented. In the literature, models typically employ the pulse waveform to derive the corresponding electromagnetic fields. However, given the Department of Defense (DoD) has incorporated the double exponential current waveform as part of their "Electromagnetic Environmental Effects Requirements For Systems", we felt it important to develop a solution for the magnetic field which utilized ...


A New Method To Describe Image Theory For An Imperfect Conductor, S L. Meredith, S K. Earles, Niescja E. Turner 2010 Trinity University

A New Method To Describe Image Theory For An Imperfect Conductor, S L. Meredith, S K. Earles, Niescja E. Turner

Physics and Astronomy Faculty Research

Problem statement: Modify the equations associated with image theory in order to account for perfect and imperfect conductors. Approach: A novel approach for describing the application of image theory for an imperfect conductive surface was presented. The method presented here purposely downplays the physics of how image theory was employed to account for a charge which is in the presence of an imperfect conductive surface. In turn, it adopted an approach which focused on the geometry that existed between the charged particle and surface ground. In doing so, the proposed method formulated a solution that had minimized the complexity of ...


First Measurement Of The Muon Neutrino Charged Current Quasielastic Double Differential Cross Section, A. Aguilar-Arevalo, Sally Koutsoliotas 2010 Bucknell University

First Measurement Of The Muon Neutrino Charged Current Quasielastic Double Differential Cross Section, A. Aguilar-Arevalo, Sally Koutsoliotas

Faculty Journal Articles

No abstract provided.


A Spitzer Search For Planetary-Mass Brown Dwarfs With Circumstellar Disks: Candidate Selection, Paul M. Harvey, Daniel T. Jaffe, Katelyn N. Allers, Michael Liu 2010 Bucknell University

A Spitzer Search For Planetary-Mass Brown Dwarfs With Circumstellar Disks: Candidate Selection, Paul M. Harvey, Daniel T. Jaffe, Katelyn N. Allers, Michael Liu

Faculty Journal Articles

No abstract provided.


The Horizontal Electric Field Induced By A Lightning Return Stroke, S L. Meredith, S K. Earles, Niescja E. Turner 2010 Trinity University

The Horizontal Electric Field Induced By A Lightning Return Stroke, S L. Meredith, S K. Earles, Niescja E. Turner

Physics and Astronomy Faculty Research

Problem statement: Develop a new formula which describes the horizontal electric field induced by a lightning return stroke in contact with an imperfect conductive surface. Approach: A new method for describing the horizontal electric field induced by a lightning return stroke will be presented. The method presented here had utilized an approach which purposely downplayed the physics of how image theory was employed in the presence of an imperfect conductive surface. It did so by adopting a technique which had focused on the geometry that existed between the lightning channel and surface ground. In doing so, new expressions for surface ...


Synchrotron Radiation By Fast Fermions In Heavy-Ion Collisions, Kirill Tuchin 2010 Iowa State University

Synchrotron Radiation By Fast Fermions In Heavy-Ion Collisions, Kirill Tuchin

Physics and Astronomy Publications

We study the synchrotron radiation of gluons by fast quarks in strong magnetic field produced by colliding relativistic heavy ions. We argue that due to high electric conductivity of plasma, the magnetic field is almost constant during the entire plasma lifetime. We calculate the energy loss due to synchrotron radiation of gluons by fast quarks. We find that the typical energy loss per unit length for a light quark at the Large Hadron Collider is a few GeV per fm. This effect alone predicts quenching of jets with p⊥ up to about 20 GeV.We also show that the spin-flip ...


A Model For Predicting Extragalactic Jet Lifetimes, Daniel S. Spicer, Robert Bingham, Stephen O'Sullivan 2010 Drexel University

A Model For Predicting Extragalactic Jet Lifetimes, Daniel S. Spicer, Robert Bingham, Stephen O'Sullivan

Articles

Abstract. In this letter, we propose a model to explain the disintegration of ex- tragalactic jets and to predict the associated timescale. The model assumes that a jet is current and charge neutral as well as collimated at its source; however, the forward electron current gradually decays producing a magnetic field transverse to the direction of jet propagation. This growing transverse magnetic field eventually causes the jet to disintegrate.


Longitudinal Scaling Property Of The Charge Balance Function In Au + Au Collisions At √Snn= 200 Gev, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, L. S. Barnby, S. Bültmann, I. Koralt, D. Plyku 2010 Old Dominion University

Longitudinal Scaling Property Of The Charge Balance Function In Au + Au Collisions At √Snn= 200 Gev, B. I. Abelev, M. M. Aggarwal, Z. Ahammed, A. V. Alakhverdyants, I. Alekseev, B. D. Anderson, D. Arkhipkin, G. S. Averichev, J. Balewski, L. S. Barnby, S. Bültmann, I. Koralt, D. Plyku

Physics Faculty Publications

We present measurements of the charge balance function, from the charged particles, for diverse pseudorapidity and transverse momentum ranges in Au + Au collisions at √sNN = 200 GeV using the STAR detector at RHIC. We observe that the balance function is boost-invariant within the pseudorapidity coverage [ − 1.3 , 1.3 ] . The balance function properly scaled by the width of the observed pseudorapidity window does not depend on the position or size of the pseudorapidity window. This scaling property also holds for particles in different transverse momentum ranges. In addition, we find that the width of the balance function decreases monotonically ...


Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani 2010 Old Dominion University

Hard Photodisintegration Of A Proton Pair, I. Pomerantz, N. Bubis, K. Allada, A. Beck, B. L. Berman, W. Boeglin, A. Camsonne, M. Canan, K. Chirapatpimol, E. Cisbani

Physics Faculty Publications

We present a study of high energy photodisintegration of proton-pairs through the γ + 3He → p + p + n channel. Photon energies, , from 0.8 to 4.7 GeV were used in kinematics corresponding to a proton pair with high relative momentum and a neutron nearly at rest. The s−11 scaling of the cross section, as predicted by the constituent counting rule for two nucleon photodisintegration, was observed for the first time. The onset of the scaling is at a higher energy and the cross section is significantly lower than for deuteron (pn pair) photodisintegration. For below the ...


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