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

Physics Commons™

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

California Polytechnic State University, San Luis Obispo

Discipline
Keyword
Publication Year
Publication
Publication Type

Articles 601 - 630 of 873

Full-Text Articles in Physics

Multistrange Baryon Production In Au-Au Collisions At √ SNn = 130 Gev, Star Collaboration, T.D. Gutierrez May 2004

Multistrange Baryon Production In Au-Au Collisions At √ SNn = 130 Gev, Star Collaboration, T.D. Gutierrez

Physics

The transverse mass spectra and midrapidity yields for Ξs and Ωs are presented. For the 10% most central collisions, the ¯Ξ¯+/h− ratio increases from the Super Proton Synchrotron to the Relativistic Heavy Ion Collider energies while the Ξ−/h−stays approximately constant. A hydrodynamically inspired model fit to the Ξ spectra, which assumes a thermalized source, seems to indicate that these multistrange particles experience a significant transverse flow effect, but are emitted when the system is hotter and the flow is smaller than values obtained from a combined fit to π, K, p, and Λs.

Go to article

Spectral Characteristics Of Water Megamaser Galaxies. Ii. Eso103-G035, Txs 2226-184, And Ic1481, N. Bennert, H. Schulz, C. Henkel May 2004

Spectral Characteristics Of Water Megamaser Galaxies. Ii. Eso103-G035, Txs 2226-184, And Ic1481, N. Bennert, H. Schulz, C. Henkel

Physics

Long-slit optical emission-line spectra of the H2O megamaser galaxies ESO 103-G035, TXS 2226-184, and IC 1481 are evaluated in order to look for characteristics typical for water-megamaser galaxies. We present rotation curves, line ratios, electron densities, temperatures, and H luminosities. The successful line-profile decompositions rest on d-Lorentzians with an additional parameter d to adjust the wings, rather than Gaussians or Lorentzians as basic functions. No significant velocity gradient is found along the major axis in the innermost 2 kpc of TXS 2226-184. IC 1481 reveals a spectrum suggestive of a vigorous starburst in the …

Go to article

Physics And Society Travels With Dave, David W. Hafemeister Apr 2004

Physics And Society Travels With Dave, David W. Hafemeister

Physics

No abstract provided.

Go to article

Magnetosome Mysteries, Richard B. Frankel, Dennis A. Bazylinski Apr 2004

Magnetosome Mysteries, Richard B. Frankel, Dennis A. Bazylinski

Physics

No abstract provided.

Go to article

Identified Particle Distributions In Pp And Au+Au Collisions At √Snn=200 Gev, Star Collaboration, T.D. Gutierrez Mar 2004

Identified Particle Distributions In Pp And Au+Au Collisions At √Snn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

Transverse mass and rapidity distributions for charged pions, charged kaons, protons, and antiprotons are reported for √sNN=200  GeV pp and Au+Au collisions at Relativistic Heary Ion Collider (RHIC). Chemical and kinetic equilibrium model fits to our data reveal strong radial flow and long duration from chemical to kinetic freeze-out in central Au+Au collisions. The chemical freeze-out temperature appears to be independent of initial conditions at RHIC energies.

Go to article

Ρ0 Production And Possible Modification In Au + Au And P + P Collisions At √SNn = 200 Gev, J. Adams, C. Adler, M.M. Aggarwal, Z. Ahammed, J. Amonett, B.D. Anderson, D. Arkhipkin, G.S. Averichev, S.K. Badyal, J. Balewski, O. Barannikova, L.S. Barnby, J. Baudot, S. Bekele, V.V. Belaga, R. Bellwied, J. Berger, B.I. Bezverkhny, S. Bhardwaj, A.K. Bhati, H. Bichsel, A. Billmeier, L.C. Bland, C.O. Blyth, B.E. Bonner, M. Botje, A. Boucham, A.V. Brandin, A. Bravar, R.V. Cadman, X.Z. Cai, H. Caines, M. Calderón De La Barca Sánchez, J. Carroll, J. Castillo, D. Cebra, P. Chaloupka, S. Chattopadhyay, H.F. Chen, Y. Chen, S.P. Chernenko, M. Cherney, A. Chikanian, W. Christie, J.P. Coffin, T.M. Cormier, J.G. Cramer, H.J. Crawford, D. Das, S. Das, A.A. Derevschikov, L. Didenko, T. Dietel, W.J. Dong, X. Dong, J.E. Draper, F. Du, A.K. Dubey, V.B. Dunin, J.C. Dunlop, M.R. Dutta Mazumadar, V. Eckardt, L.G. Efimov, V. Emelianov, J. Engelage, G. Eppley, B. Erazmus, M. Estienne, P. Fachini, V. Fine, J. Faivre, R. Fatemi, K. Filimonov, P. Filip, E. Finch, Y. Fisyak, D. Flierl, K.J. Foley, J. Fu, C.A. Gagliardi, N. Gagunashvili, J. Gans, M.S. Ganti, L. Gaudichet, F. Geurts, V. Ghazikhanian, P. Ghosh, J.E. Gonzalez, O. Grachov, O. Grebenyuk, S. Gronstal, D. Grosnick, S.M. Guertin, A. Gupta, Thomas D. Gutierrez, T.J. Hallman, A. Hamed, D. Hardtke, J.W. Harris, M. Heinz, T.W. Henry, S. Hepplemann, B. Hippolyte, A. Hirsch, E. Hjort, G.W. Hoffmann, M. Horsley, H.Z. Huang, S.L. Huang, E. Hughes, T.J. Humanic, G. Igo, A. Ishihara, P. Jacobs, W.W. Jacobs, M. Janik, H. Jiang, I. Johnson, P.G. Jones, E.G. Judd, S. Kabana, M. Kaplan, D. Keane, V.Yu. Khodyrev, J. Kiryluk, A. Kisiel, J. Klay, S.R. Klein, A. Klyachko, D.D. Koetke, T. Kollegger, M. Kopytine, L. Kotchenda, A.D. Kovalenko, M. Kramer, P. Kravtsov, V.I. Kravtsov, K. Krueger, C. Kuhn, A.I. Kulikov, A. Kumar, G.J. Kunde, C.L. Kunz, R. Kh. Kutuev, A.A. Kuznetsov, M.A.C. Lamont, J.M. Landgraf, S. Lange, B. Lasiuk, F. Laue, J. Lauret, A. Lebedev, R. Lednicky, M.J. Levine, C. Li, Q Li, S.J. Lindenbaum, M.A. Lisa, F. Liu, L. Liu, Z. Liu, Q.J. Liu, T. Ljubicic, W.J. Llope, H. Long, R.S. Longacre, M. Lopez-Noriega, W.A. Love, T. Ludlam, D. Lynn, J. Ma, Y.G. Ma, D. Magestro, S. Mahajan, L.K. Mangotra, D.P. Mahapatra, R. Majka, R. Manweiler, S. Margetis, C. Markert, L. Martin, J.N. Marx, H.S. Matis, Yu.A. Matulenko, C.J. Mcclain, T.S. Mcshane, F. Meissner, Yu. Melnick, A. Meschanin, M.L. Miller, Z. Milosevich, N.G. Minaev, C. Mironov, A. Mischke, D.K. Mishra, J. Mitchell, B. Mohanty, L. Molnar, C.F. Moore, M.J. Mora-Corral, D.A. Morozov, V. Morozov, M.M De Moura, M.G. Munhoz, B.K. Nandi, S.K. Nayak, T.K. Nayak, J.M. Nelson, P.K. Netrakanti, V.A. Nikitin, L.V. Nogach, B. Norman, S.B. Nurushev, G. Odyniec, A. Ogawa, V. Okorokov, M. Oldenburg, D. Olson, G. Paic, S.K. Pal, Y. Panebratsev, S.Y. Panitkin, A.I. Pavlinov, T. Pawlak, T. Peitzmann, V. Perevoztchikov, C. Perkins, W. Peryt, V.A. Petrov, S.C. Phatak, R. Picha, M. Planinic, J. Pluta, N. Porile, J. Porter, A.M. Poskanzer, M. Potekhin, E. Potrebenikova, B.V.K.S. Potukuchi, D. Prindle, C. Pruneau, J. Putschke, G. Rai, G. Rakness, R. Raniwala, S. Raniwala, O. Ravel, R.L. Ray, S.V. Razin, D. Reichhold, J.G. Reid, G. Renault, F. Retiere, A. Ridiger, H.G. Ritter, J.B. Roberts, O.V. Rogachevskiy, J.L. Romero, A. Rose, C. Roy, L. Ruan, R. Sahoo, I. Sakrejda, S. Salur, J. Sandweiss, I. Savin, J. Schambach, R.P. Scharenberg, N. Schmitz, L.S. Schroeder, K. Schweda, J. Seger, P. Seyboth, E. Shahaliev, M. Shao, W. Shao, M. Sharma, K.E. Shestermanov, S.S. Shimanskiy, R.N. Singaraju, F. Simon, G. Skoro, N. Smirnov, R. Snellings, G. Sood, P. Sorensen, J. Sowinski, J. Speltz, H.M. Spinka, B. Srivastava, T.D.S. Stanislaus, R. Stock, A. Stolpovsky, M. Strikhanov, B. Stringfellow, C. Struck, A.A.P. Suaide, E. Sugarbaker, C. Suire, M. Šumbera, B. Surrow, T.J.M. Symons, A. Szanto De Toledo, P. Szarwas, A. Tai, J. Takahashi, A.H. Tang, D. Thein, J.H. Thomas, S. Timoshenko, M. Tokarev, M.B. Tonjes, T.A. Trainor, S. Trentalange, R.E. Tribble, O.D. Tsai, T. Ullrich, D.G. Underwood, G. Van Buren, A.M. Vander Molen, R. Varma, I.M. Vasilevski, A.N. Vasiliev, R. Vernet, S.E. Vigdor, Y.P. Viyogi, S.A. Voloshin, M. Vznunzdaev, W.T. Waggoner, F. Wang, G. Wang, G. Wang, X.L. Wang, Y. Wang, Z.M. Wang, H. Ward, J.W. Watson, J.C. Webb, R. Wells, G.D. Westfall, C. A. Whitten Jr., H. Wieman, R. Willson, S.W. Wissink, R. Witt, J. Wood, J. Wu, N. Xu, Z. Xu, Z.Z. Xu, E. Yamamoto, P. Yepes, V.I. Yurevich, B. Yuting, Y.V. Zanevski, H. Zhang, W.M. Zhang, Z.P. Zhang, Z.P. Zhaomin, Z.P. Zizong, P.A. Zolnierczuk, R. Zoulkarneev, Y. Zoulkarneeva, A.N. Zubarev Mar 2004

Ρ0 Production And Possible Modification In Au + Au And P + P Collisions At √SNn = 200 Gev, J. Adams, C. Adler, M.M. Aggarwal, Z. Ahammed, J. Amonett, B.D. Anderson, D. Arkhipkin, G.S. Averichev, S.K. Badyal, J. Balewski, O. Barannikova, L.S. Barnby, J. Baudot, S. Bekele, V.V. Belaga, R. Bellwied, J. Berger, B.I. Bezverkhny, S. Bhardwaj, A.K. Bhati, H. Bichsel, A. Billmeier, L.C. Bland, C.O. Blyth, B.E. Bonner, M. Botje, A. Boucham, A.V. Brandin, A. Bravar, R.V. Cadman, X.Z. Cai, H. Caines, M. Calderón De La Barca Sánchez, J. Carroll, J. Castillo, D. Cebra, P. Chaloupka, S. Chattopadhyay, H.F. Chen, Y. Chen, S.P. Chernenko, M. Cherney, A. Chikanian, W. Christie, J.P. Coffin, T.M. Cormier, J.G. Cramer, H.J. Crawford, D. Das, S. Das, A.A. Derevschikov, L. Didenko, T. Dietel, W.J. Dong, X. Dong, J.E. Draper, F. Du, A.K. Dubey, V.B. Dunin, J.C. Dunlop, M.R. Dutta Mazumadar, V. Eckardt, L.G. Efimov, V. Emelianov, J. Engelage, G. Eppley, B. Erazmus, M. Estienne, P. Fachini, V. Fine, J. Faivre, R. Fatemi, K. Filimonov, P. Filip, E. Finch, Y. Fisyak, D. Flierl, K.J. Foley, J. Fu, C.A. Gagliardi, N. Gagunashvili, J. Gans, M.S. Ganti, L. Gaudichet, F. Geurts, V. Ghazikhanian, P. Ghosh, J.E. Gonzalez, O. Grachov, O. Grebenyuk, S. Gronstal, D. Grosnick, S.M. Guertin, A. Gupta, Thomas D. Gutierrez, T.J. Hallman, A. Hamed, D. Hardtke, J.W. Harris, M. Heinz, T.W. Henry, S. Hepplemann, B. Hippolyte, A. Hirsch, E. Hjort, G.W. Hoffmann, M. Horsley, H.Z. Huang, S.L. Huang, E. Hughes, T.J. Humanic, G. Igo, A. Ishihara, P. Jacobs, W.W. Jacobs, M. Janik, H. Jiang, I. Johnson, P.G. Jones, E.G. Judd, S. Kabana, M. Kaplan, D. Keane, V.Yu. Khodyrev, J. Kiryluk, A. Kisiel, J. Klay, S.R. Klein, A. Klyachko, D.D. Koetke, T. Kollegger, M. Kopytine, L. Kotchenda, A.D. Kovalenko, M. Kramer, P. Kravtsov, V.I. Kravtsov, K. Krueger, C. Kuhn, A.I. Kulikov, A. Kumar, G.J. Kunde, C.L. Kunz, R. Kh. Kutuev, A.A. Kuznetsov, M.A.C. Lamont, J.M. Landgraf, S. Lange, B. Lasiuk, F. Laue, J. Lauret, A. Lebedev, R. Lednicky, M.J. Levine, C. Li, Q Li, S.J. Lindenbaum, M.A. Lisa, F. Liu, L. Liu, Z. Liu, Q.J. Liu, T. Ljubicic, W.J. Llope, H. Long, R.S. Longacre, M. Lopez-Noriega, W.A. Love, T. Ludlam, D. Lynn, J. Ma, Y.G. Ma, D. Magestro, S. Mahajan, L.K. Mangotra, D.P. Mahapatra, R. Majka, R. Manweiler, S. Margetis, C. Markert, L. Martin, J.N. Marx, H.S. Matis, Yu.A. Matulenko, C.J. Mcclain, T.S. Mcshane, F. Meissner, Yu. Melnick, A. Meschanin, M.L. Miller, Z. Milosevich, N.G. Minaev, C. Mironov, A. Mischke, D.K. Mishra, J. Mitchell, B. Mohanty, L. Molnar, C.F. Moore, M.J. Mora-Corral, D.A. Morozov, V. Morozov, M.M De Moura, M.G. Munhoz, B.K. Nandi, S.K. Nayak, T.K. Nayak, J.M. Nelson, P.K. Netrakanti, V.A. Nikitin, L.V. Nogach, B. Norman, S.B. Nurushev, G. Odyniec, A. Ogawa, V. Okorokov, M. Oldenburg, D. Olson, G. Paic, S.K. Pal, Y. Panebratsev, S.Y. Panitkin, A.I. Pavlinov, T. Pawlak, T. Peitzmann, V. Perevoztchikov, C. Perkins, W. Peryt, V.A. Petrov, S.C. Phatak, R. Picha, M. Planinic, J. Pluta, N. Porile, J. Porter, A.M. Poskanzer, M. Potekhin, E. Potrebenikova, B.V.K.S. Potukuchi, D. Prindle, C. Pruneau, J. Putschke, G. Rai, G. Rakness, R. Raniwala, S. Raniwala, O. Ravel, R.L. Ray, S.V. Razin, D. Reichhold, J.G. Reid, G. Renault, F. Retiere, A. Ridiger, H.G. Ritter, J.B. Roberts, O.V. Rogachevskiy, J.L. Romero, A. Rose, C. Roy, L. Ruan, R. Sahoo, I. Sakrejda, S. Salur, J. Sandweiss, I. Savin, J. Schambach, R.P. Scharenberg, N. Schmitz, L.S. Schroeder, K. Schweda, J. Seger, P. Seyboth, E. Shahaliev, M. Shao, W. Shao, M. Sharma, K.E. Shestermanov, S.S. Shimanskiy, R.N. Singaraju, F. Simon, G. Skoro, N. Smirnov, R. Snellings, G. Sood, P. Sorensen, J. Sowinski, J. Speltz, H.M. Spinka, B. Srivastava, T.D.S. Stanislaus, R. Stock, A. Stolpovsky, M. Strikhanov, B. Stringfellow, C. Struck, A.A.P. Suaide, E. Sugarbaker, C. Suire, M. Šumbera, B. Surrow, T.J.M. Symons, A. Szanto De Toledo, P. Szarwas, A. Tai, J. Takahashi, A.H. Tang, D. Thein, J.H. Thomas, S. Timoshenko, M. Tokarev, M.B. Tonjes, T.A. Trainor, S. Trentalange, R.E. Tribble, O.D. Tsai, T. Ullrich, D.G. Underwood, G. Van Buren, A.M. Vander Molen, R. Varma, I.M. Vasilevski, A.N. Vasiliev, R. Vernet, S.E. Vigdor, Y.P. Viyogi, S.A. Voloshin, M. Vznunzdaev, W.T. Waggoner, F. Wang, G. Wang, G. Wang, X.L. Wang, Y. Wang, Z.M. Wang, H. Ward, J.W. Watson, J.C. Webb, R. Wells, G.D. Westfall, C. A. Whitten Jr., H. Wieman, R. Willson, S.W. Wissink, R. Witt, J. Wood, J. Wu, N. Xu, Z. Xu, Z.Z. Xu, E. Yamamoto, P. Yepes, V.I. Yurevich, B. Yuting, Y.V. Zanevski, H. Zhang, W.M. Zhang, Z.P. Zhang, Z.P. Zhaomin, Z.P. Zizong, P.A. Zolnierczuk, R. Zoulkarneev, Y. Zoulkarneeva, A.N. Zubarev

Physics

We report results on ρ(770)0→π+π− production at midrapidity in p+p and peripheral Au+Au collisions at √sNN=200  GeV. This is the first direct measurement of ρ(770)0→π+π− in heavy-ion collisions. The measured ρ0 peak in the invariant mass distribution is shifted by ∼40  MeV/c2 in minimum bias p+p interactions and ∼70  MeV/c2 in peripheral Au+Au collisions. The ρ0 mass shift is dependent on transverse momentum and multiplicity. The modification of the ρ0 meson mass, width, and shape due to phase space and dynamical effects are discussed.

Go to article

Magnetosome Formation In Prokaryotes, Dennis A. Bazylinski, Richard B. Frankel Mar 2004

Magnetosome Formation In Prokaryotes, Dennis A. Bazylinski, Richard B. Frankel

Physics

Magnetotactic bacteria were discovered almost 30 years ago, and for many years and many different reasons, the number of researchers working in this field was few and progress was slow. Recently, however, thanks to the isolation of new strains and the development of new techniques for manipulating these strains, researchers from several laboratories have made significant progress in elucidating the molecular, biochemical, chemical and genetic bases of magnetosome formation and understanding how these unique intracellular organelles function. We focus here on this progress.

Go to article

Azimuthal Anisotropy At The Relativistic Heavy Ion Collider: The First And Fourth Harmonics, Star Collaboration, T.D. Gutierrez Feb 2004

Azimuthal Anisotropy At The Relativistic Heavy Ion Collider: The First And Fourth Harmonics, Star Collaboration, T.D. Gutierrez

Physics

We report the first observations of the first harmonic (directed flow, v1) and the fourth harmonic (v4), in the azimuthal distribution of particles with respect to the reaction plane in Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC). Both measurements were done taking advantage of the large elliptic flow (v2) generated at RHIC. From the correlation of v2 with v1 it is determined that v2 is positive, or in-plane. The integrated v4 is about a factor of 10 smaller than v2. For the sixth (v6 …

Go to article

Reply To Comment By R. Bousquet Et Al. On “Subduction Factory: 1. Theoretical Mineralogy, Densities, Seismic Wave Speeds And H2O Contents”, Bradley R. Hacker, Geoffrey A. Abers, Simon M. Peacock, Scott Joshnston Feb 2004

Reply To Comment By R. Bousquet Et Al. On “Subduction Factory: 1. Theoretical Mineralogy, Densities, Seismic Wave Speeds And H2O Contents”, Bradley R. Hacker, Geoffrey A. Abers, Simon M. Peacock, Scott Joshnston

Physics

No abstract provided.

Go to article

Refractive-Index Measurements Of Zinc Germanium Diphosphide At 300 And 77 K By Use Of A Modified Michelson Interferometer, Glen D. Gillen, Shekhar Guha Jan 2004

Refractive-Index Measurements Of Zinc Germanium Diphosphide At 300 And 77 K By Use Of A Modified Michelson Interferometer, Glen D. Gillen, Shekhar Guha

Physics

A method to determine the absolute refractive index of materials available in the shape of flat wafers with parallel sides by using interferometric techniques is presented. With this method, nondestructive, sample-specific measurements can be made. The method is tested by using silicon, germanium and zinc selenide, and measurements for both the ordinary and extraordinary axes of ZnGeP2 for temperatures of 300 and 77 K are reported.

Go to article

One- And Two-Dimensional Optical Lattices On A Chip For Quantum Computing, Katharina Gillen-Christandl, Gregory P. Lafyatis, Seung-Cheol Lee, Jin-Fa Lee Jan 2004

One- And Two-Dimensional Optical Lattices On A Chip For Quantum Computing, Katharina Gillen-Christandl, Gregory P. Lafyatis, Seung-Cheol Lee, Jin-Fa Lee

Physics

We propose a way to make arrays of optical frequency dipole-force microtraps for cold atoms above a dielectric substrate. Traps are nodes in the evanescent wave fields above an optical waveguide resulting from interference of different waveguide modes. The traps have features sought in developing neutral atom based architectures for quantum computing: ∼1 mW of laser power yields very tight traps 150 nm above a waveguide with trap vibrational frequencies ∼1 MHz and vibrational ground state sizes ∼10 nm. The arrays are scalable and allow addressing of individual sites for quantum logic operations.

Go to article

Revolving Door Scenario For Congressional Fellows, David W. Hafemeister Jan 2004

Revolving Door Scenario For Congressional Fellows, David W. Hafemeister

Physics

No abstract provided.

Go to article

A High Precision Radial Velocity Survey Of K Giants, David S. Mitchell Jan 2004

A High Precision Radial Velocity Survey Of K Giants, David S. Mitchell

Physics

Precise radial velocity measurements of stars can provide a powerful tool for both examining the intrinsic atmospheric activity of the star, and testing for the existence of substellar orbital companions. This method has been used to detect the vast majority of known extrasolar planets, as well as probing the asteroseismological characteristics of active stars. This dissertation presents the results of a precise radial velocity survey of 177 bright K giant stars. Six of the stars have data that indicate the presence of planetary or brown dwarf orbital companions. Many others have evidence of nonradial pulsations, and twenty binary stars are …

Go to article

Pion-Kaon Correlations In Central Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez Dec 2003

Pion-Kaon Correlations In Central Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

Pion-kaon correlation functions are constructed from central Au+Au STAR data taken at √sNN=130  GeV by the STAR detector at the Relativistic Heavy Ion Collider (RHIC). The results suggest that pions and kaons are not emitted at the same average space-time point. Space-momentum correlations, i.e., transverse flow, lead to a space-time emission asymmetry of pions and kaons that is consistent with the data. This result provides new independent evidence that the system created at RHIC undergoes a collective transverse expansion.

Go to article

Three-Pion Hanbury Brown–Twiss Correlations In Relativistic Heavy-Ion Collisions From The Star Experiment, Star Collaboration, T.D. Gutierrez Dec 2003

Three-Pion Hanbury Brown–Twiss Correlations In Relativistic Heavy-Ion Collisions From The Star Experiment, Star Collaboration, T.D. Gutierrez

Physics

Data from the first physics run at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory, Au+Au collisions at √sNN=130   GeV, have been analyzed by the STAR Collaboration using three-pion correlations with charged pions to study whether pions are emitted independently at freeze-out. We have made a high-statistics measurement of the three-pion correlation function and calculated the normalized three-particle correlator to obtain a quantitative measurement of the degree of chaoticity of the pion source. It is found that the degree of chaoticity seems to increase with increasing particle multiplicity.

Go to article

Energy Scaling Law For Buildings, David W. Hafemeister Dec 2003

Energy Scaling Law For Buildings, David W. Hafemeister

Physics

This paper is an ode to my friend Hendrik. We collaborated on hyperfine interactions from 1962 to 1984, when he was colleague and friend. Since then I have been working on the Physics of Societal Issues (Springer Verlag, 2003). The paper below models energy use in buildings, which could save considerable energy with well-designed buildings.

Go to article

Biological Permanent Magnets, Richard B. Frankel Dec 2003

Biological Permanent Magnets, Richard B. Frankel

Physics

Magnetotactic bacteria orient and migrate along magnetic field lines. Each cell is essentially a self-propelled magnetic dipole. The magnetic properties of these bacteria have been determined by a variety of techniques, including pulsed hysteresis measurements on single cells.

Go to article

Computer-Controlled In-Class Feedback System For Interactive Lectures, Thomas J. Bensky Nov 2003

Computer-Controlled In-Class Feedback System For Interactive Lectures, Thomas J. Bensky

Physics

Instructors who wish to implement an interactive lecture style, such as peer instruction, have the need to collect feedback from students in a lecture environment. We present a computer-controlled electronic circuit that allows for quick, rigorous, and accurate measurement and reporting of student feedback in the lecture environment.

Go to article

Net Charge Fluctuations In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez Oct 2003

Net Charge Fluctuations In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We present the results of charged particle fluctuations measurements in Au+Au collisions at √sNN=130 GeV using the STAR detector. Dynamical fluctuations measurements are presented for inclusive charged particle multiplicities as well as for identified charged pions, kaons, and protons. The net charge dynamical fluctuations are found to be large and negative providing clear evidence that positive and negative charged particle production is correlated within the pseudorapidity range investigated. Correlations are smaller than expected based on model-dependent predictions for a resonance gas or a quark-gluon gas which undergoes fast hadronization and freeze-out. Qualitative agreement is found with comparable scaled …

Go to article

Ξ‾ And Ω Distributions In Hadron–Nucleus Interactions, R. Vogt, Thomas D. Gutierrez Oct 2003

Ξ‾ And Ω Distributions In Hadron–Nucleus Interactions, R. Vogt, Thomas D. Gutierrez

Physics

Strange baryons have long been known to exhibit a leading particle effect. A recent comparison of Ξ‾ production in π‾, n, and Σ‾ interactions with nuclei show this effect clearly. These data are supplemented by earlier measurements of Ξ‾ and Ω production by a Ξ‾ beam. We calculate the Ξ‾ and Ω xF distributions and nuclear dependence in hA interactions using the intrinsic model.

Go to article

Application Of Interferometric Wave Propagation For Refractive Index Measurements Of Solids, Glen D. Gillen, Shekhar Guha Oct 2003

Application Of Interferometric Wave Propagation For Refractive Index Measurements Of Solids, Glen D. Gillen, Shekhar Guha

Physics

The output signal of a modified Michelson interferometer with a flat-parallel sample, whose normal is oriented at an arbitrary angle with respect to the laser path, placed in one arm is analyzed. The interferometric pattern as a function of angle is calculated, and used to determine the absolute refractive index.

Go to article

Analysis Of Resonance Structure In The Above-Threshold Ionization Photoelectron Spectra Of Magnesium, Glen D. Gillen, L D. Van Woerkom Sep 2003

Analysis Of Resonance Structure In The Above-Threshold Ionization Photoelectron Spectra Of Magnesium, Glen D. Gillen, L D. Van Woerkom

Physics

Using high-resolution photoelectron spectroscopy and 120-fs, 800-nm Ti:sapphire laser pulses, we observe and analyze intensity-dependent resonant population of specific intermediate excited states of neutral magnesium atoms and their subsequent photoionization in the laser field. Various participating states are identified using angular-momentum selection rules, partial yields, and angular distributions. Several unexpected results are observed and discussed, including peaks that do not correspond to expected resonant processes, and order-to-order variations in the photoelectron spectra.

Go to article

Driven Depinning Of Strongly Disordered Media And Anisotropic Mean-Field Limits, M. Christina Marchetti, A. Alan Middleton, Karl Saunders, J. M. Schwarz Sep 2003

Driven Depinning Of Strongly Disordered Media And Anisotropic Mean-Field Limits, M. Christina Marchetti, A. Alan Middleton, Karl Saunders, J. M. Schwarz

Physics

Extended systems driven through strong disorder are modeled generically using coarse-grained degrees of freedom that interact elastically in the directions parallel to the drive and slip along at least one of the directions transverse to the motion. In the limit of infinite-range elastic and viscous coupling this model has a tricritical point separating a region where the depinning is continuous, in the universality class of elastic depinning, from a region where depinning is hysteretic. Many of the collective transport models discussed in the literature are special cases of the generic model.

Go to article

Radio Polarization Of The Young High-Magnetic-Field Pulsar Psr J1119-6127, Fronefield Crawford, Nathan C. Keim Jun 2003

Radio Polarization Of The Young High-Magnetic-Field Pulsar Psr J1119-6127, Fronefield Crawford, Nathan C. Keim

Physics

We have investigated the radio polarization properties of PSR J1119-6127, a recently discovered young radio pulsar with a large magnetic field. Using pulsar-gated radio imaging data taken at a center frequency of 2496 MHz with the Australia Telescope Compact Array, we have determined a rotation measure for the pulsar of +842 +/- 23 rad m^-2. These data, combined with archival polarimetry data taken at a center frequency of 1366 MHz with the Parkes telescope, were used to determine the polarization characteristics of PSR J1119-6127 at both frequencies. The pulsar has a fractional linear polarization of ~75% and ~55% at 1366 …

Go to article

Review Of Tritium On Ice: The Dangerous New Alliance Of Nuclear Weapons And Nuclear Power By Kenneth D. Bergeron, David W. Hafemeister May 2003

Review Of Tritium On Ice: The Dangerous New Alliance Of Nuclear Weapons And Nuclear Power By Kenneth D. Bergeron, David W. Hafemeister

Physics

No abstract provided.

Go to article

Searching For Planetary Transits In The Field Of Open Cluster Ngc 6819 – I, R. A. Street, Keith Horne, T. A. Lister, A. Penny, Y. Tsapras, A. Quirrenbach, N. Safizadeh, David Mitchell, J. Cooke, A. Collier Cameron Apr 2003

Searching For Planetary Transits In The Field Of Open Cluster Ngc 6819 – I, R. A. Street, Keith Horne, T. A. Lister, A. Penny, Y. Tsapras, A. Quirrenbach, N. Safizadeh, David Mitchell, J. Cooke, A. Collier Cameron

Physics

We present results from our survey for planetary transits in the field of the intermediate-age (∼2.5 Gyr), metal-rich ([Fe/H] ∼+0.07) open cluster NGC 6819. We have obtained high-precision time-series photometry for over 38 000 stars in this field and have developed an effective matched-filter algorithm to search for photometric transits. This algorithm identified 8 candidate stars showing multiple transit-like events, plus 3 stars with single eclipses. On closer inspection, while most are shown to be low-mass stellar binaries, some of these events could be the result of brown dwarf companions. The data for one of the single-transit candidates indicate a …

Go to article

Electrical And Spectroscopic Studies Of The Effects Of Dc Electric Fields On Pre-Mixed Propane-Air Flames, S D. Marcum, G D. Gillen, B N. Ganguly Jan 2003

Electrical And Spectroscopic Studies Of The Effects Of Dc Electric Fields On Pre-Mixed Propane-Air Flames, S D. Marcum, G D. Gillen, B N. Ganguly

Physics

The effects of DC electric fields on temperature distributions within pre-mixed propane-air flames have been measured by the technique of thin filament pyrometry (TFP). We have focussed on the dramatic electric-field-induced modifications of the shape and size of the inner cone and the concomitant changes in the temperature profiles of fuel-rich mixtures with equivalence ratios of 1-1.35. Temperature profile measurements show large decreases in the reaction zone volume that is dependent upon the applied voltage polarity, indicating that electron impact excitation is not responsible for the observed effects. Additionally, the observed flame temperature profile modifications are not strongly dependent on …

Go to article

Us Nuclear Security Cooperation With Russia And Transparency, David W. Hafemeister Jan 2003

Us Nuclear Security Cooperation With Russia And Transparency, David W. Hafemeister

Physics

This chapter reviews the efforts of Russia and the United States to conclude agreements on the control or reduction of their inventories of nuclear warheads and military fissile materials. While some of the negotiations attempted to codify arms limitation and reduction measures, others were aimed at constraining the spread of fissile materials and technologies to the non-nuclear weapon states (NNWS). A number of the negotiations had elements of both arms control and non-proliferation.

Most of the monitoring provisions contained in nuclear agreements between Russia and the USA are in the category of transparency measures—those that give confidence that a …

Go to article

Measurement Of The Index Of Refraction Of A Flat Zinc Germanium Phosphide Wafer In The Infrared, Glen Gillen, Shekhar Guha Jan 2003

Measurement Of The Index Of Refraction Of A Flat Zinc Germanium Phosphide Wafer In The Infrared, Glen Gillen, Shekhar Guha

Physics

We have developed and tested a novel application of interferometry to determine the absolute refractive index of individual infrared materials having flat and parallel surfaces without alteration of the sample in any way, and measured no for ZnGeP2.

Go to article

Viscoelasticity From A Microscopic Model Of Dislocation Dynamics, M. Christina Marchetti, Karl Saunders Dec 2002

Viscoelasticity From A Microscopic Model Of Dislocation Dynamics, M. Christina Marchetti, Karl Saunders

Physics

It is shown that the dynamics of a viscoelastic medium can be modeled as that of a two-dimensional crystal with a finite concentration of dislocations, as well as vacancy and interstitial defects. At the longest length scales the viscoelasticity is described by the simplest Maxwell model, whose shear and compressional relaxation times are obtained in terms of microscopic quantities, including the density of free dislocations. At short length scales, t bond orientational order effects become important and lead to wave vector dependent corrections to the relaxation times.

Go to article

First Prev Next Last