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Full-Text Articles in Physical Sciences and Mathematics

Pseudorapidity Asymmetry And Centrality Dependence Of Charged Hadron Spectra In D+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez Dec 2004

Pseudorapidity Asymmetry And Centrality Dependence Of Charged Hadron Spectra In D+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

The pseudorapidity asymmetry and centrality dependence of charged hadron spectra in d+Au collisions at √sNN=200 GeV are presented. The charged particle density at midrapidity, its pseudorapidity asymmetry, and centrality dependence are reasonably reproduced by a multiphase transport model, by HIJING, and by the latest calculations in a saturation model. Ratios of transverse momentum spectra between backward and forward pseudorapidity are above unity for pT below 5GeV ∕ c. The ratio of central to peripheral spectra in d+Au collisions shows enhancement at 2 < pT < 6GeV ∕ c, with a larger effect at backward rapidity than forward rapidity. Our measurements are in qualitative agreement with gluon saturation and in contrast to calculations based on incoherent multiple partonic scatterings.


Azimuthal Anisotropy And Correlations At Large Transverse Momenta In P+P And Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez Dec 2004

Azimuthal Anisotropy And Correlations At Large Transverse Momenta In P+P And Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

Results on high transverse momentum charged particle emission with respect to the reaction plane are presented for Au+Au collisions at √sNN=200  GeV. Two- and four-particle correlations results are presented as well as a comparison of azimuthal correlations in Au+Au collisions to those in p+p at the same energy. The elliptic anisotropy v2 is found to reach its maximum at pt∼3  GeV/c, then decrease slowly and remain significant up to pt≈7–10  GeV/c. Stronger suppression is found in the back-to-back high-pt particle correlations for particles emitted out of plane compared to those emitted in plane. The …


Measurements Of Transverse Energy Distributions In Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez Nov 2004

Measurements Of Transverse Energy Distributions In Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

Transverse energy (ET) distributions have been measured for Au+Au collisions at √sNN=200GeV by the STAR Collaboration at RHIC. ET is constructed from its hadronic and electromagnetic components, which have been measured separately. ET production for the most central collisions is well described by several theoretical models whose common feature is large energy density achieved early in the fireball evolution. The magnitude and centrality dependence of ET per charged particle agrees well with measurements at lower collision energy, indicating that the growth in ET for larger collision energy results from the growth in …


Photon And Neutral Pion Production In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez Oct 2004

Photon And Neutral Pion Production In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We report inclusive photon measurements about midrapidity (∣y∣<0.5) from 197Au+197Au collisions at √sNN=130 GeV at RHIC. Photon pair conversions were reconstructed from electron and positron tracks measured with the Time Projection Chamber (TPC) of the STAR experiment. With this method, an energy resolution of ΔE ∕ E≈2% at 0.5GeV has been achieved. Reconstructed photons have also been used to measure the transverse momentum (pt) spectra of π0mesons about midrapidity (∣y∣<1) via the π0→γγ decay channel. The fractional contribution of the π0→γγ decay to the inclusive photon spectrum decreases by 20%±5% between pt …


Rapidity And Centrality Dependence Of Proton And Antiproton Production From 197Au + 197Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez Oct 2004

Rapidity And Centrality Dependence Of Proton And Antiproton Production From 197Au + 197Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We report on the rapidity and centrality dependence of proton and antiproton transverse mass distributions from 197Au+197Au collisions at √sNN=130 GeV as measured by the STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Our results are from the rapidity and transverse momentum range of ∣y∣<0.5 and 0.35 < pt < 1.00 GeV ∕ c. For both protons and antiprotons, transverse mass distributions become more convex from peripheral to central collisions demonstrating characteristics of collective expansion. The measured rapidity distributions and the mean transverse momenta versus rapidity are flat within ∣y∣<0.5. Comparisons of our data with results from model calculations indicate that in order to obtain a consistent picture of the proton (antiproton) yields and transverse mass distributions the possibility of prehadronic collective expansion may have to be taken into account.


Centrality And Pseudorapidity Dependence Of Charged Hadron Production At Intermediate PT In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez Oct 2004

Centrality And Pseudorapidity Dependence Of Charged Hadron Production At Intermediate PT In Au+Au Collisions At √SNn=130 Gev, Star Collaboration, T.D. Gutierrez

Physics

We present STAR measurements of charged hadron production as a function of centrality in Au+Au collisions at √sNN=130 GeV. The measurements cover a phase space region of 0.2T<6.0GeV∕c in transverse momentum and −1<η<1 in pseudorapidity. Inclusive transverse momentum distributions of charged hadrons in the pseudorapidity region 0.5<∣η∣<1 are reported and compared to our previously published results for ∣η∣<0.5. No significant difference is seen for inclusive pT distributions of charged hadrons in these two pseudorapidity bins. We measured dN∕dη distributions and truncated mean pT in a region of pT>pTcut, and studied the results in the framework of participant and binary scaling. No clear evidence is observed for participant scaling of charged hadron yield in the measured pT region. The relative importance of hard scattering processes is investigated through binary …


Spatiotemporal Distribution Of Marine Magnetotactic Bacteria In A Seasonally Stratified Coastal Salt Pond, S. L. Simmons, S. M. Sievert, Richard B. Frankel, Dennis A. Bazylinski, K. J. Edwards Oct 2004

Spatiotemporal Distribution Of Marine Magnetotactic Bacteria In A Seasonally Stratified Coastal Salt Pond, S. L. Simmons, S. M. Sievert, Richard B. Frankel, Dennis A. Bazylinski, K. J. Edwards

Physics

The occurrence and distribution of magnetotactic bacteria (MB) were studied as a function of the physical and chemical conditions in meromictic Salt Pond, Falmouth, Mass., throughout summer 2002. Three dominant MB morphotypes were observed to occur within the chemocline. Small microaerophilic magnetite-producing cocci were present at the top of the chemocline, while a greigite-producing packet-forming bacterium occurred at the base of the chemocline. The distributions of these groups displayed sharp changes in abundance over small length scales within the water column as well as strong seasonal fluctuations in population abundance. We identified a novel, greigite-producing rod in the sulfidic hypolimnion …


Sequential Interferometric Techniques For Measuring Independent Values Of The Refractive Index And Material Thickness Of Semiconductor Wafers, Glen D. Gillen, Shekhar Guha Oct 2004

Sequential Interferometric Techniques For Measuring Independent Values Of The Refractive Index And Material Thickness Of Semiconductor Wafers, Glen D. Gillen, Shekhar Guha

Physics

A technique is presented using both Michelson and Fabry-Perot interferometry to independently measure the refractive index and the material thickness of semiconductor wafers. The method does not require accurate prior knowledge of either quantity.


Production Of E+E Pairs Accompanied By Nuclear Dissociation In Ultraperipheral Heavy-Ion Collisions, Star Collaboration, T.D. Gutierrez Sep 2004

Production Of E+E− Pairs Accompanied By Nuclear Dissociation In Ultraperipheral Heavy-Ion Collisions, Star Collaboration, T.D. Gutierrez

Physics

We present data on e+e pair production accompanied by nuclear breakup in ultraperipheral gold-gold collisions at a center of mass energy of 200GeV per nucleon pair. The nuclear breakup requirement selects events at small impact parameters, where higher-order diagrams for pair production should be enhanced. We compare the data with two calculations: one based on the equivalent photon approximation, and the other using lowest-order quantum electrodynamics (QED). The data distributions agree with both calculations, except that the pair transverse momentum spectrum disagrees with the equivalent photon approach. We set limits on higher-order contributions to the cross section.


Superconducting Transition Edge Sensor Using Dilute Almn Alloys, S. W. Deiker, W. Doriese, G. C. Hilton, K. D. Hilton, W. H. Rippard, J. N. Ullom, L. R. Vale, S. T. Ruggiero, A. Williams, Betty A. Young Sep 2004

Superconducting Transition Edge Sensor Using Dilute Almn Alloys, S. W. Deiker, W. Doriese, G. C. Hilton, K. D. Hilton, W. H. Rippard, J. N. Ullom, L. R. Vale, S. T. Ruggiero, A. Williams, Betty A. Young

Physics

We have fabricated a bolometer using a transition-edge sensor (TES) made of Al doped with Mn to suppress the superconducting critical temperature (Tc) of Al from ∼1Kto∼100mK. The resulting detector exhibits low-frequency noise consistent with theory, with a noise-equivalent power of 7.5×10−18W/√Hz. The addition of Mn impurities did not significantly increase the heat capacity of the TES. In addition, the detector is surprisingly insensitive to applied magnetic fields. The use of AlMn alloy films in arrays of TES detectors has advantages in simplicity of fabrication when compared to traditional bilayer fabrication techniques.


Modeling And Propagation Of Near-Field Diffraction Patterns: A More Complete Approach, Glen D. Gillen, Shekhar Guha Sep 2004

Modeling And Propagation Of Near-Field Diffraction Patterns: A More Complete Approach, Glen D. Gillen, Shekhar Guha

Physics

We discuss the origins and regions of validity of various near-field diffraction models. The complete Rayleigh–Sommerfeld model is found to accurately represent intensity distributions for axial distances up to and including the location of the aperture, a region where commonly used models fail. We show that near-field diffraction theory can be applied to the refraction of light at an interface between two different media yielding results that demonstrate the validity of Snell’s law in the presence of diffraction. Calculations using near-field diffraction and Fourier optics are compared to experimentally measured intensity distributions


Enhancement Of Curie Temperature In Ga1−XMnXAs Epilayers Grown On Cross-Hatched InYGa1−YAs Buffer Layers, O. Maksimov, B.L. Sheu, G. Xiang, N. Keim, P. Schiffer, N. Samarth Sep 2004

Enhancement Of Curie Temperature In Ga1−XMnXAs Epilayers Grown On Cross-Hatched InYGa1−YAs Buffer Layers, O. Maksimov, B.L. Sheu, G. Xiang, N. Keim, P. Schiffer, N. Samarth

Physics

Relaxed InyGa1−yAs epilayers grown on (0 0 1) GaAs are known to exhibit a cross-hatched surface with ridges running along the [1 1 0] and directions. We find that Ga1−xMnxAs epilayers grown on such buffer layers can have as-grown Curie temperatures (TC) that are higher than the as-grown 110 K value typical of Ga1−xMnxAs/GaAs heterostructures. Further, low-temperature annealing leads to only modest additional increases in TC, contrasting with the behavior in Ga1−xMnxAs/GaAs where TC …


Mean-Field Theory Of Collective Transport With Phase Slips, Karl Saunders, J. M. Schwarz, M. Christina Marchetti, A. Alan Middleton Jul 2004

Mean-Field Theory Of Collective Transport With Phase Slips, Karl Saunders, J. M. Schwarz, M. Christina Marchetti, A. Alan Middleton

Physics

The driven transport of plastic systems in various disordered backgrounds is studied within mean field theory. Plasticity is modeled using nonconvex interparticle potentials that allow for phase slips. This theory most naturally describes sliding charge density waves; other applications include flow of colloidal particles or driven magnetic flux vortices in disordered backgrounds. The phase diagrams exhibit generic phases and phase boundaries, though the shapes of the phase boundaries depend on the shape of the disorder potential. The phases are distinguished by their velocity and coherence: the moving phase generically has finite coherence, while pinned states can be coherent or incoherent. …


National Academy Of Sciences Study On The Comprehensive Nuclear Test Ban Treaty, David W. Hafemeister Jul 2004

National Academy Of Sciences Study On The Comprehensive Nuclear Test Ban Treaty, David W. Hafemeister

Physics

No abstract provided.


Azimuthally Sensitive Hanbury Brown–Twiss Interferometry In Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez Jun 2004

Azimuthally Sensitive Hanbury Brown–Twiss Interferometry In Au+Au Collisions At √SNn=200 Gev, Star Collaboration, T.D. Gutierrez

Physics

We present the results of a systematic study of the shape of the pion distribution in coordinate space at freeze-out in Au+Au collisions at BNL RHIC using two-pion Hanbury Brown–Twiss (HBT) interferometry. Oscillations of the extracted HBT radii versus emission angle indicate sources elongated perpendicular to the reaction plane. The results indicate that the pressure and expansion time of the collision system are not sufficient to completely quench its initial shape.


Intensity Interferometry With Anyons, Thomas D. Gutierrez Jun 2004

Intensity Interferometry With Anyons, Thomas D. Gutierrez

Physics

A pairwise correlation function in relative momentum space is discussed as a tool to characterize the properties of an incoherent source of noninteracting Abelian anyons. This is analogous to the Hanbury-Brown Twiss effect for particles with fractional statistics in two dimensions. In particular, using a flux tube model for anyons, the effects of source shape and quantum statistics on a two-particle correlation function are examined. Such a tool may prove useful in the context of quantum computing and other experimental applications where studying anyon sources are of interest.


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−/hstays 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.


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 …


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

Physics And Society Travels With Dave, David W. Hafemeister

Physics

No abstract provided.


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

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

Physics

No abstract provided.


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.


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.


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.


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 …


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.


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.


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.


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

Revolving Door Scenario For Congressional Fellows, David W. Hafemeister

Physics

No abstract provided.


The Parsec-Scale Structure And Jet Motions Of The Tev Blazars 1es 1959+650, Pks 2155-304, And 1es 2344+514, B. Glenn Piner, Philip G. Edwards Jan 2004

The Parsec-Scale Structure And Jet Motions Of The Tev Blazars 1es 1959+650, Pks 2155-304, And 1es 2344+514, B. Glenn Piner, Philip G. Edwards

Physics

As part of our study of the VLBI properties of TeV blazar jets, we present here a series of high-resolution 15 GHz Very Long Baseline Array (VLBA) images of the parsec-scale jets of the TeV blazars 1ES 1959+650, PKS 2155-304, and 1ES 2344+514, with linear resolutions of ~0.5 pc. Each of these sources was observed with the VLBA at three or four epochs during 1999 and 2000. There is a notable lack of any strong moving components on the VLBI images (in contrast to the rapid superluminal motions seen in EGRET blazars), and the structure of the VLBI jet can …


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 …