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1. Spin decoherence and off-resonance behavior of radio-frequency-driven spin rotations in storage rings

Author

N. N. Nikolaev, F. Rathmann, J. Slim, A. Andres, V. Hejny, A. Nass, A. Kacharava, P. Lenisa, J. Pretz, A. Saleev, V. Shmakova, H. Soltner, F. Abusaif, A. Aggarwal, A. Aksentev, B. Alberdi, L. Barion, I. Bekman, M. Beyß, C. Böhme, B. Breitkreutz, N. Canale, G. Ciullo, S. Dymov, N.-O. Fröhlich, R. Gebel, M. Gaisser, K. Grigoryev, D. Grzonka, J. Hetzel, O. Javakhishvili, V. Kamerdzhiev, S. Karanth, I. Keshelashvili, A. Kononov, K. Laihem, A. Lehrach, N. Lomidze, B. Lorentz, G. Macharashvili, A. Magiera, D. Mchedlishvili, A. Melnikov, F. Müller, A. Pesce, V. Poncza, D. Prasuhn, D. Shergelashvili, N. Shurkhno, S. Siddique, A. Silenko, S. Stassen, E. J. Stephenson, H. Ströher, M. Tabidze, G. Tagliente, Y. Valdau, M. Vitz, T. Wagner, A. Wirzba, A. Wrońska, P. Wüstner, and M. Żurek

Subjects
Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

High-frequency driven resonant spin rotators are routinely used as standard instruments in polarization experiments in particle and nuclear physics. Maintaining the continuous exact parametric spin resonance condition of the equality of the spin rotator and the spin precession frequency during operation is one of the challenges. We present a detailed analytical description of the effects of detuning the exact spin resonance on the precessing vertical and in-plane components of the polarization. An important part of the formalism presented here is the consideration of experimentally relevant spin decoherence effects. Within the developed formalism, we address the impact of feedback via pilot-bunch-based comagnetometry on continuous spin flips and on the related interpretation of charged-particle electric dipole moment searches using storage rings. We propose a spin-flip-based tomography of the longitudinal profile of polarization in a bunch, which is important for the evaluation of the polarization-dependent luminosity in collider experiments. We emphasize the potential importance of the previously unexplored phase of the horizontal polarization of the envelope as an indicator of the stability of radio-frequency-driven spin rotations in storage rings and as a testing ground for spin decoherence mechanisms.

Published
2024
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2. First Search for Axionlike Particles in a Storage Ring Using a Polarized Deuteron Beam

Author

S. Karanth, E. J. Stephenson, S. P. Chang, V. Hejny, S. Park, J. Pretz, Y. K. Semertzidis, A. Wirzba, A. Wrońska, F. Abusaif, A. Aggarwal, A. Aksentev, B. Alberdi, A. Andres, L. Barion, I. Bekman, M. Beyß, C. Böhme, B. Breitkreutz, C. von Byern, N. Canale, G. Ciullo, S. Dymov, N.-O. Fröhlich, R. Gebel, K. Grigoryev, D. Grzonka, J. Hetzel, O. Javakhishvili, H. Jeong, A. Kacharava, V. Kamerdzhiev, I. Keshelashvili, A. Kononov, K. Laihem, A. Lehrach, P. Lenisa, N. Lomidze, B. Lorentz, A. Magiera, D. Mchedlishvili, F. Müller, A. Nass, N. N. Nikolaev, A. Pesce, V. Poncza, D. Prasuhn, F. Rathmann, A. Saleev, D. Shergelashvili, V. Shmakova, N. Shurkhno, S. Siddique, J. Slim, H. Soltner, R. Stassen, H. Ströher, M. Tabidze, G. Tagliente, Y. Valdau, M. Vitz, T. Wagner, and P. Wüstner

Subjects
Physics, QC1-999
Abstract

Based on the notion that the local dark-matter field of axions or axionlike particles (ALPs) in our Galaxy induces oscillating couplings to the spins of nucleons and nuclei (via the electric dipole moment of the latter and/or the paramagnetic axion-wind effect), we establish the feasibility of a new method to search for ALPs in storage rings. Based on previous work that allows us to maintain the in-plane polarization of a stored deuteron beam for a few hundred seconds, we perform a first proof-of-principle experiment at the Cooler Synchrotron (COSY) to scan momenta near 970 MeV/c. This entails a scan of the spin-precession frequency. At resonance between the spin-precession frequency of deuterons and the ALP-induced electric dipole moment (EDM) oscillation frequency, there is an accumulation of the polarization component out of the ring plane. Since the axion frequency is unknown, the momentum of the beam and, consequently, the spin-precession frequency are ramped to search for a vertical polarization change that occurs when the resonance is crossed. At COSY, four beam bunches with different polarization directions are used to make sure that no resonance is missed because of the unknown relative phase between the polarization precession and the axion or ALP field. A frequency window of 1.5 kHz width around the spin-precession frequency of 121 kHz is scanned. We describe the experimental procedure and a test of the methodology with the help of a radio-frequency Wien filter located on the COSY ring. No ALP resonance is observed. As a consequence, an upper limit of the oscillating EDM component of the deuteron as well as its axion coupling constants are provided.

Published
2023
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3. Connection between zero chromaticity and long in-plane polarization lifetime in a magnetic storage ring

Author

G. Guidoboni, E. J. Stephenson, A. Wrońska, Z. Bagdasarian, J. Bsaisou, S. Chekmenev, G. Ciullo, S. Dymov, D. Eversmann, M. Gaisser, R. Gebel, V. Hejny, N. Hempelmann, F. Hinder, A. Kacharava, I. Keshelashvili, P. Kulessa, P. Lenisa, A. Lehrach, B. Lorentz, P. Maanen, R. Maier, D. Mchedlishvili, S. Mey, A. Nass, A. Pesce, Y. Orlov, J. Pretz, D. Prasuhn, F. Rathmann, M. Rosenthal, A. Saleev, Y. K. Semertzidis, Y. Senichev, V. Shmakova, H. Stockhorst, H. Ströher, R. Talman, P. Thörngren Engblom, F. Trinkel, Yu. Valdau, C. Weidemann, P. Wüstner, M. Żurek, and D. Zyuzin

Subjects
Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

In this paper, we demonstrate the connection between a magnetic storage ring with additional sextupole fields set so that the x and y chromaticities vanish and the maximizing of the lifetime of in-plane polarization (IPP) for a 0.97-GeV/c deuteron beam. The IPP magnitude was measured by continuously monitoring the down-up scattering asymmetry (sensitive to sideways polarization) in an in-beam, carbon-target polarimeter and unfolding the precession of the IPP due to the magnetic anomaly of the deuteron. The optimum operating conditions for a long IPP lifetime were made by scanning the field of the storage ring sextupole magnet families while observing the rate of IPP loss during storage of the beam. The beam was bunched and electron cooled. The IPP losses appear to arise from the change of the orbit circumference, and consequently the particle speed and spin tune, due to the transverse betatron oscillations of individual particles in the beam. The effects of these changes are canceled by an appropriate sextupole field setting.

Published
2018
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4. Measuring the polarization of a rapidly precessing deuteron beam

Author

Z. Bagdasarian, S. Bertelli, D. Chiladze, G. Ciullo, J. Dietrich, S. Dymov, D. Eversmann, G. Fanourakis, M. Gaisser, R. Gebel, B. Gou, G. Guidoboni, V. Hejny, A. Kacharava, V. Kamerdzhiev, A. Lehrach, P. Lenisa, B. Lorentz, L. Magallanes, R. Maier, D. Mchedlishvili, W. M. Morse, A. Nass, D. Oellers, A. Pesce, D. Prasuhn, J. Pretz, F. Rathmann, V. Shmakova, Y. K. Semertzidis, E. J. Stephenson, H. Stockhorst, H. Ströher, R. Talman, P. Thörngren Engblom, Yu. Valdau, C. Weidemann, and P. Wüstner

Subjects
Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

This paper describes a time-marking system that enables a measurement of the in-plane (horizontal) polarization of a 0.97-GeV/c deuteron beam circulating in the Cooler Synchrotron (COSY) at the Forschungszentrum Jülich. The clock time of each polarimeter event is used to unfold the 120-kHz spin precession and assign events to bins according to the direction of the horizontal polarization. After accumulation for one or more seconds, the down-up scattering asymmetry can be calculated for each direction and matched to a sinusoidal function whose magnitude is proportional to the horizontal polarization. This requires prior knowledge of the spin tune or polarization precession rate. An initial estimate is refined by resorting the events as the spin tune is adjusted across a narrow range and searching for the maximum polarization magnitude. The result is biased toward polarization values that are too large, in part because of statistical fluctuations but also because sinusoidal fits to even random data will produce sizable magnitudes when the phase is left free to vary. An analysis procedure is described that matches the time dependence of the horizontal polarization to templates based on emittance-driven polarization loss while correcting for the positive bias. This information will be used to study ways to extend the horizontal polarization lifetime by correcting spin tune spread using ring sextupole fields and thereby to support the feasibility of searching for an intrinsic electric dipole moment using polarized beams in a storage ring. This paper is a combined effort of the Storage Ring EDM collaboration and the JEDI collaboration.

Published
2014
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5. Erratum: Synchrotron oscillation effects on an rf-solenoid spin resonance [Phys. Rev. ST Accel. Beams 15, 124202 (2012)]

Author

P. Benati, D. Chiladze, J. Dietrich, M. Gaisser, R. Gebel, G. Guidoboni, V. Hejny, A. Kacharava, V. Kamerdzhiev, P. Kulessa, A. Lehrach, P. Lenisa, B. Lorentz, R. Maier, D. Mchedlishvili, W. M. Morse, D. Öllers, A. Pesce, A. Polyanskiy, D. Prasuhn, F. Rathmann, Y. K. Semertzidis, E. J. Stephenson, H. Stockhorst, H. Ströher, R. Talman, Yu. Valdau, Ch. Weidemann, and P. Wüstner

Subjects
Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Published
2013
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6. Synchrotron oscillation effects on an rf-solenoid spin resonance

Author

P. Benati, D. Chiladze, J. Dietrich, M. Gaisser, R. Gebel, G. Guidoboni, V. Hejny, A. Kacharava, V. Kamerdzhiev, P. Kulessa, A. Lehrach, P. Lenisa, B. Lorentz, R. Maier, D. Mchedlishvili, W. M. Morse, D. Öllers, A. Pesce, A. Polyanskiy, D. Prasuhn, F. Rathmann, Y. K. Semertzidis, E. J. Stephenson, H. Stockhorst, H. Ströher, R. Talman, Yu. Valdau, Ch. Weidemann, and P. Wüstner

Subjects
Nuclear and particle physics. Atomic energy. Radioactivity, QC770-798
Abstract

New measurements are reported for the time dependence of the vertical polarization of a 0.97 GeV/c deuteron beam circulating in a storage ring and perturbed by an rf solenoid. The storage ring is the cooler synchrotron (COSY) located at the Forschungszentrum Jülich. The beam polarization was measured continuously using a 1.5 cm thick carbon target located at the edge of the circulating deuteron beam and the scintillators of the EDDA detector. An rf solenoid mounted on the ring was used to generate fields at and near the frequency of the 1-Gγ spin resonance. Measurements were made of the vertical beam polarization as a function of time with the operation of the rf solenoid in either fixed or continuously variable frequency mode. Using rf-solenoid strengths as large as 2.66×10^{-5} revolutions/turn, slow oscillations (∼1 Hz) were observed in the vertical beam polarization. When the circulating beam was continuously electron cooled, these oscillations completely reversed the polarization and showed no sign of diminishing in amplitude. But for the uncooled beam, the oscillation amplitude was damped to nearly zero within a few seconds. A simple spin-tracking model without the details of the COSY ring lattice was successful in reproducing these oscillations and demonstrating the sensitivity of the damping to the magnitude of the synchrotron motion of the beam particles. The model demonstrates that the characteristic features of measurements made in the presence of large synchrotron oscillations are distinct from the features of such measurements when made off resonance. These data were collected in preparation for a study of the spin coherence time, a beam property that needs to become long to enable a search for an electric dipole moment using a storage ring.

Published
2012
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7. Erratum: Azimuthal Anisotropy of KS0 and Λ+Λ¯ Production at Midrapidity from Au+Au Collisions at sNN=130 GeV [Phys. Rev. Lett. 89 , 132301 (2002)]

Author

S. P. Chernenko, W. J. Llope, A. Cardenas, H. Long, R. Lednický, V. A. Nikitin, K. E. Shestermanov, A. Stolpovsky, R. S. Longacre, W. Christie, L. Kotchenda, H. Bichsel, P. Seyboth, V. Trofimov, Guy Paic, A. Chikanian, A. V. Brandin, S. S. Shimanskii, A. I. Kulikov, Masashi Kaneta, W. M. Zhang, L. C. Bland, Y. Panebratsev, R.Kh. Kutuev, Andrey Vasiliev, Joram Berger, T. Todoroki, Adam Ryszard Kisiel, J. B. Carroll, A. E. Yakutin, G. Igo, M. Oldenburg, H. J. Crawford, M. Castro, M. Calderon De La Barca Sanchez, G. Rai, J. W. Mitchell, N. Schmitz, Janet Elizabeth Seger, VL Rykov, B. D. Anderson, V. Petrov, E. Shahaliev, A. Boucham, T. J. Humanic, V. B. Dunin, A. C. Saulys, Z. Z. Xu, Q. Li, R. Witt, S. E. Vigdor, T. W. Henry, Christian Claude Kuhn, W. S. Deng, V. Ghazikhanian, Nikita Smirnov, I.A. Savin, M. Csanád, A. I. Pavlinov, F. Liu, M. B. Tonjes, J. W. Harris, B. E. Bonner, N. T. Porile, O. D. Tsai, J. L. Romero, Mirko Planinic, H. M. Spinka, C. E. Allgower, G. Eppley, S. Bekele, V. Morozov, Michael Kramer, M. Cherney, B. Lasiuk, E. Finch, Thomas Michael Cormier, R. Willson, D. G. Underwood, Michael W. Anderson, E. Gushin, P. Yepes, V. Eckardt, R. Ma, P. Nevski, J. H. Thomas, D. Hardtke, F. Laue, A. H. Tang, R. D. Majka, J. Pluta, L. Liu, V. M. Leontiev, Olivier Ravel, G. LoCurto, C. O. Blyth, E. Hjort, I. Zborovský, Yu A. Matulenko, M. Horsley, G. Skoro, B. Stringfellow, T. S. McShane, Rene Bellwied, C. P. Lansdell, R. E. Tribble, R.J.M. Snellings, Gerald W Hoffmann, J. N. Marx, B. Choi, J. G. Cramer, Thomas Dietel, Alexander Kovalenko, L. V. Nogach, A. P. Meschanin, Y. Fisyak, Ian Johnson, Christophe Pierre Suire, J. Sowinski, J. Schambach, D. Reichhold, T. J. M. Symons, T. Niida, A. Lebedev, M. M. de Moura, A. Szanto de Toledo, T. Pawlak, Morton Kaplan, P. Sorensen, G. Van Buren, Sevil Salur, Saurabh Pandey, A. Tai, T. W. Ludlam, J. Amonett, J. M. Nelson, V. Emelianov, D. Keane, W. Peryt, R. Stock, L. G. Efimov, D. Seliverstov, A. Schüttauf, G. S. Averichev, J. Porter, C. Roy, A. Klyachko, Vladimir Tikhomirov, P. Chaloupka, S. Trentalange, A. Ishihara, Yu Chen, Gregory Rakness, B. K. Srivastava, I. M. Vasilevski, F. Retiere, J. Gans, Boris Hippolyte, J. C. Dunlop, Zubayer Ahammed, M. J. LeVine, H. G. Ritter, A. S. Konstantinov, B. Norman, A. A. Kuznetsov, S. Y. Panitkin, E. Yamamoto, J. Engelage, David Lynn, J. G. Ma, J. Takahashi, M. A. C. Lamont, S. B. Nurushev, Z. Milosevich, N. G. Minaev, Sergey Voloshin, K. J. Foley, V. S. Shvetcov, Q. J. Liu, C. A. Whitten, J. Baudot, A. Rose, Y. V. Zanevski, S. Lange, S. J. Lindenbaum, Yu. Ivanshin, N. Xu, John N. Wood, M. Guedon, A. M. Poskanzer, A. M. VanderMolen, Russell Wells, J. M. Landgraf, M. Strikhanov, A. Billmeier, J. Putschke, J. W. Watson, A. Ogawa, Thomas A. Trainor, R. P. Scharenberg, Christina Markert, H. S. Matis, G. Odyniec, J. Sandweiss, Z. Liu, W. W. Jacobs, G. D. Westfall, H. Ward, L. S. Schroeder, S. V. Razin, L. Gaudichet, H. Zhang, Jay Roberts, Jinghui Yang, Malgorzata Anna Janik, C. L. Kunz, K. Krueger, C. F. Moore, C. Struck, M. Lopez-Noriega, I. Sakrejda, M. L. Miller, Fuqiang Wang, P. Szarwas, A. S. Hirsch, P. M. Jacobs, P. Kravtsov, C. Adler, E. G. Judd, Michael A. Thompson, Michal Sumbera, Jeffrey G. Reid, A. A. P. Suaide, E. Sugarbaker, S. R. Klein, V. Faine, J. Castillo, S. W. Wissink, J. E. Draper, H. Z. Huang, N.D. Gagunashvili, O. Barannikova, D. L. Olson, Sukalyan Chattopadhyay, T. J. Hallman, V. Perevoztchikov, K. Filimonov, A. A. Derevschikov, Marie Germain, V. I. Yurevich, A. N. Zubarev, M. Messer, P. Fachini, V. V. Belaga, Peter Graham Jones, Lee Stuart Barnby, F. Meissner, L. Didenko, M. Kopytine, J. Fu, M. Tokarev, K. Schweda, H. H. Wieman, J. Kiryluk, Rajarshi Ray, L. Lakehal-Ayat, W. A. Love, Vitaly Okorokov, Bernd Surrow, J. L. Klay, C. A. Gagliardi, A. Ridiger, T. Herston, R. V. Cadman, S. Heppelmann, D. Flierl, Frank Jm Geurts, L. Martin, J. P. Coffin, O. V. Rogachevski, V. A. Moiseenko, Marcelo Gameiro Munhoz, D. J. Prindle, E. J. Stephenson, M. A. Lisa, S. Margetis, O. A. Grachov, B. Erazmus, Gerd Joachim Kunde, D. Cebra, A. Bravar, Yu Melnick, J. Balewski, Claude Andre Pruneau, T. Ullrich, R. Zoulkarneev, V. Grigoriev, E. Potrebenikova, T. Ljubicic, and H. Caines

Subjects
Physics, Nuclear physics, Azimuth, General Physics and Astronomy, Anisotropy
Published
2021
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8. Precision measurements of differential cross sections and analyzing powers in elastic deuteron-deuteron scattering at 65 MeV/nucleon

Author

Nasser Kalantar-Nayestanaki, M. Mahjour-Shafiei, E. J. Stephenson, St. Kistryn, H. Tavakoli-Zaniani, J. G. Messchendorp, R. Ramazani-Sharifabadi, A. Deltuva, Mohammad Eslami-Kalantari, A. Ramazani-Moghaddam-Arani, H. Mardanpour, E. Stephan, M. Mohammadi-Dadkan, A. Kozela, H. R. Amir-Ahmadi, C. D. Bailey, and Research unit Nuclear & Hadron Physics

Subjects
Physics, Elastic scattering, Nuclear and High Energy Physics, Scattering, Hadron, Nuclear Theory, nucleon, FOS: Physical sciences, Observable, four-nucleon system, elastic scattering, analyzing power, Nuclear physics, differential cross sections, Nuclear fusion, Nuclear Experiment (nucl-ex), Nucleon, Nuclear Experiment, Beam (structure), Spin-½
Abstract

We present measurements of differential cross sections and analyzing powers for the elastic 2H(~d; d)d scattering process. The data were obtained using a 130 MeV polarized deuteron beam. Cross sections and spin observables of the elastic scattering process were measured at the AGOR facility at KVI using two independent setups, namely BINA and BBS. The data harvest at setups are in excellent agreement with each other and allowed us to carry out a thorough systematic analysis to provide the most accurate data in elastic deuteron-deuteron scattering at intermediate energies. The results can be used to confront upcoming state-of-the-art calculations in the four-nucleon scattering domain, and will, thereby, provide further insights in the dynamics of three- and four-nucleon forces in few-nucleon systems., 10 pages, 7 figures

Published
2021

9. Influence of electron cooling on the polarization lifetime of a horizontally polarized storage ring beam

Author

Andreas Lehrach, G. Guidoboni, P. Lenisa, D. Prasuhn, V. Shmakova, I. Keshelashvili, Ralf Gebel, B. Lorentz, H. Ströher, A. Nass, Frank Rathmann, A.K. Kacharava, E. J. Stephenson, A. Pesce, D. Mchedlishvili, Yu. Valdau, J. Pretz, Richard Talman, Aleksandra Wrońska, A. Saleev, S. Dymov, Y. Senichev, C. Weidemann, S. Karanth, Nikolai N. Nikolaev, V. Hejny, G. Ciullo, and P. Wüstner

Subjects
Accelerator Physics (physics.acc-ph), Nuclear and High Energy Physics, Field (physics), Electron cooling, Socio-culturale, FOS: Physical sciences, Spin coherence time, 01 natural sciences, law.invention, PE2_2, Optics, PE2_1, law, Polarization, 0103 physical sciences, ddc:530, Polarization, Spin coherence time, Electron cooling, 010306 general physics, PE2_3, Instrumentation, Spin-½, Physics, 010308 nuclear & particles physics, business.industry, Polarization (waves), Deuterium, Physics::Accelerator Physics, Physics - Accelerator Physics, business, Intensity (heat transfer), Beam (structure), Storage ring
Abstract

A previous publication has shown that the in-plane polarization (IPP) component of a polarized 0.97-GeV/c deuteron beam in the COSY storage ring may acquire a polarization half-life in excess of 1000 s through a combination of beam bunching, electron cooling (prior to any spin manipulation), sextupole field adjustment, and a limitation of the beam intensity. This paper documents further tests pointing to additional gains in the IPP lifetime if cooling is active throughout the beam store., 11 pages, 6 figures Submitted to Physical Review Accelerators and Beams

Published
2020
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10. Measurement of the neutron decay electron-antineutrino angular correlation by the aCORN experiment

Author

Gordon L. Jones, G. Darius, E. J. Stephenson, Maynard S. Dewey, M. P. Mendenhall, C. DeAngelis, Fred E. Wietfeldt, M. T. Hassan, B. Collett, G. Noid, Jeffrey S. Nico, Thomas R. Gentile, Fred B. Bateman, A. Komives, and W. A. Byron

Subjects
Physics, Coupling constant, Particle physics, Proton, media_common.quotation_subject, Nuclear Theory, Center (category theory), FOS: Physical sciences, Electron, Lambda, Asymmetry, High Energy Physics::Experiment, Neutron, Nuclear Experiment (nucl-ex), Nuclear Experiment, Electron neutrino, media_common
Abstract

The aCORN experiment measures the neutron decay electron-antineutrino correlation ($a$-coefficient) using a novel method based on an asymmetry in proton time-of-flight for events where the beta electron and recoil proton are detected in delayed coincidence. We report the data analysis and result from the second run at the NIST Center for Neutron Research, using the high-flux cold neutron beam on the new NG-C neutron guide end position: $a = -0.10758 \pm 0.00136 (\mbox{stat}) \pm 0.00148 (\mbox{sys})$. This is consistent within uncertainties with the result from the first aCORN run on the NG-6 cold neutron beam. Combining the two aCORN runs we obtain $a = -0.10782 \pm 0.00124 (\mbox{stat}) \pm 0.00133 (\mbox{sys})$, which has an overall relative standard uncertainty of 1.7 \%. The corresponding result for the ratio of weak coupling constants $\lambda = G_A/G_V$ is $\lambda = -1.2796\pm 0.0062$., Comment: 44 pages, 30 figures

Published
2020
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11. The aCORN Backscatter-Suppressed Beta Spectrometer

Author

B. Collett, A. Laptev, Gordon L. Jones, M. T. Hassan, Jeffrey S. Nico, G. Darius, Maynard S. Dewey, Fred B. Bateman, C. Trull, G. Noid, I. Stern, Fred E. Wietfeldt, A. Komives, E. J. Stephenson, M. P. Mendenhall, and C. DeAngelis

Subjects
Nuclear and High Energy Physics, Physics - Instrumentation and Detectors, Backscatter, Physics::Instrumentation and Detectors, FOS: Physical sciences, Electron, Scintillator, 01 natural sciences, Article, Nuclear physics, Optics, 0103 physical sciences, Neutron, 010306 general physics, Nuclear Experiment, Instrumentation, Physics, Spectrometer, 010308 nuclear & particles physics, business.industry, Detector, Instrumentation and Detectors (physics.ins-det), Beta (plasma physics), Scintillation counter, High Energy Physics::Experiment, business
Abstract

Backscatter of electrons from a beta spectrometer, with incomplete energy deposition, can lead to undesirable effects in many types of experiments. We present and discuss the design and operation of a backscatter-suppressed beta spectrometer that was developed as part of a program to measure the electron-antineutrino correlation coefficient in neutron beta decay (aCORN). An array of backscatter veto detectors surrounds a plastic scintillator beta energy detector. The spectrometer contains an axial magnetic field gradient, so electrons are efficiently admitted but have a low probability for escaping back through the entrance after backscattering. The design, construction, calibration, and performance of the spectrometer are discussed., 15 figures

Published
2019

13. Realization of Spin-dependent p-C Scattering in GEANT4 and Its Application To Storage Ring Experiment For pEDM

Author

Seongtae Park, Hoyong Jeong, E. J. Stephenson, Yannis K. Semertzidis, Eunil Won, and Eleni Petrakou

Subjects
Elastic scattering, Azimuth, Physics, Physics::Instrumentation and Detectors, Scattering, Beam tilt, Detector, Gas electron multiplier, Polarimeter, Nuclear Experiment, Storage ring, Computational physics
Abstract

The Center for Axion and Precision Physics Research (CAPP) of the Institute for Basic Science (IBS) is attempting to develop prototype polarimeter detector using gas electron multiplier (GEM) technology for the storage ring proton EDM (SR pEDM) experiment. Systematic errors in the polarimeter mainly come from geometric characteristics of the polarimeter and beam dynamics. Such as beam tilt, shift or detector misalignment etc. can be sources of errors. This investigation of systematic errors has been done with GEANT4 simulation package modified by ourselves. The modified GEANT4 can calculate spin-dependent hadron elastic cross-section of proton-carbon scattering, unlike the original one. This research will explain how to realize spin-dependent hadronic elastic scattering in the azimuth angle and demonstrate its application to the geometric error related systematic error study of polarimeter.

Published
2018
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14. Phase measurement for driven spin oscillations in a storage ring

Author

S. Mey, P. Zupranski, L. Barion, M. S. Nioradze, A. Saleev, Martin Berz, D. Mchedlishvili, G. Guidoboni, E. J. Stephenson, Aleksandra Wrońska, R. Talman, Yu. N. Uzikov, H. Stockhorst, C. Weidemann, P. Wuestner, J. Slim, Dirk Heberling, D. Eversmann, P. Maanen, V. Schmidt, A. Stahl, B. Lorentz, W. Augustyniak, J. Pretz, K. Grigoryev, M. Bai, N.L. Lomidze, J. Hetzel, Alexander J. Silenko, H. Stroeher, Yu. Valdau, Nikolai N. Nikolaev, S. Dymov, D. Prasuhn, V. Hejny, Y. Semertzidis, E. Valetov, F. Mueller, Paolo Lenisa, H. Soltner, V. Shmakova, S. Chekmenev, A. Magiera, Rolf Stassen, F. Hinder, G.G. Macharashvili, G. Ciullo, G. Tagliente, A. Vassiliev, D. Grzonka, Ivan Koop, M. Gaisser, A.K. Kacharava, N. Hempelmann, Andreas Lehrach, A. Kulikov, I. Keshelashvili, M. D. Tabidze, Martin Rosenthal, Maria Zurek, F. Trinkel, Pia Thörngren Engblom, V. Kamerdzhiev, Y. Senichev, A. Nass, Frank Rathmann, Z. Bagdasarian, A. Pesce, Ralf Gebel, and Publica

Subjects
Physics, Physics and Astronomy (miscellaneous), Nuclear and High Energy Physics, Surfaces and Interfaces, Accelerator Physics (physics.acc-ph), 010308 nuclear & particles physics, Socio-culturale, FOS: Physical sciences, Polarization (waves), 01 natural sciences, 13.40.Em, 11.30.Er, 29.20.D, 29.20.dg, 29.20.db, Physical Sciences, 0103 physical sciences, lcsh:QC770-798, Fysik, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, Physics - Accelerator Physics, ddc:530, Radio frequency, Atomic physics, 010306 general physics, Storage ring
Abstract

Physical review accelerators and beams 21(4), 042002 (2018). doi:10.1103/PhysRevAccelBeams.21.042002, Published by American Physical Society, College Park, MD

Published
2018
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15. aCORN: An experiment to measure the electron-antineutrino correlation coefficient in free neutron decay

Author

Wangchun Chen, K. J. S. Stockton, I. Stern, A. Laptev, Thomas R. Gentile, H. Park, Jeffrey S. Nico, E. J. Stephenson, Gordon L. Jones, C. DeAngelis, J. Byrne, M. P. Mendenhall, W. K. Bauder, G. Darius, B. Collett, Maynard S. Dewey, G. Noid, B. G. Yerozolimsky, A. Komives, Fred E. Wietfeldt, W. A. Byron, Fred B. Bateman, M. T. Hassan, and C. Trull

Subjects
Physics, Physics - Instrumentation and Detectors, Correlation coefficient, Proton, 010308 nuclear & particles physics, media_common.quotation_subject, Measure (physics), FOS: Physical sciences, Instrumentation and Detectors (physics.ins-det), 01 natural sciences, Asymmetry, Article, Nuclear physics, Data acquisition, 0103 physical sciences, Neutron, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Instrumentation, Electron neutrino, media_common, Data reduction
Abstract

We describe an apparatus used to measure the electron-antineutrino angular correlation coefficient in free neutron decay. The apparatus employs a novel measurement technique in which the angular correlation is converted into a proton time-of-flight asymmetry that is counted directly, avoiding the need for proton spectroscopy. Details of the method, apparatus, detectors, data acquisition, and data reduction scheme are presented, along with a discussion of the important systematic effects., Comment: 21 pages, 25 figures

Published
2017

16. Phase Locking the Spin Precession in a Storage Ring

Author

Z. Bagdasarian, A. Pesce, Martin Berz, M. Bai, D. Mchedlishvili, D. Prasuhn, Ralf Gebel, E. Valetov, Dirk Heberling, Frank Rathmann, D. Grzonka, E. J. Stephenson, M. Żurek, P. Zupranski, H. Stockhorst, V. Shmakova, Andreas Lehrach, M. D. Tabidze, L. Barion, Aleksandra Wrońska, A. Stahl, B. Lorentz, J. Hetzel, Ivan Koop, D. Eversmann, G.G. Macharashvili, A. Saleev, P. Maanen, M. Gaisser, V. Kamerdzhiev, A. Magiera, G. Guidoboni, F. Müller, W. Augustyniak, P. Wüstner, J. Pretz, F. J. Etzkorn, G. Ciullo, A. Nass, S. Mey, I. Keshelashvili, H. Ströher, A. Kulikov, Nikolai N. Nikolaev, S. Chekmenev, S. Dymov, R. Stassen, F. Trinkel, C. Weidemann, J. Slim, V. Schmidt, Yu. Valdau, A. Silenko, N.L. Lomidze, Helmut Soltner, Y. Semertzidis, Martin Rosenthal, R. Talman, Yu. N. Uzikov, Paolo Lenisa, T. Hanraths, F. Hinder, A. Vassiliev, N. Hempelmann, K. Grigoryev, V. Hejny, G. Tagliente, A.K. Kacharava, and P. Thörngren Engblom

Subjects
Accelerator Physics (physics.acc-ph), Socio-culturale, FOS: Physical sciences, General Physics and Astronomy, 01 natural sciences, Beam Polarization, Sine wave, Nuclear magnetic resonance, storage rings, 0103 physical sciences, ddc:550, Accelerators, storage rings, Beam Polarization, EDM search, 010306 general physics, Physics, Spin polarization, 010308 nuclear & particles physics, Horizontal plane, Polarization (waves), Charged particle, Electric dipole moment, EDM search, Physics::Accelerator Physics, Physics - Accelerator Physics, Radio frequency, Atomic physics, Accelerators, Storage ring
Abstract

This letter reports the successful use of feedback from a spin polarization measurement to the revolution frequency of a 0.97 GeV/$c$ bunched and polarized deuteron beam in the Cooler Synchrotron (COSY) storage ring in order to control both the precession rate ($\approx 121$ kHz) and the phase of the horizontal polarization component. Real time synchronization with a radio frequency (rf) solenoid made possible the rotation of the polarization out of the horizontal plane, yielding a demonstration of the feedback method to manipulate the polarization. In particular, the rotation rate shows a sinusoidal function of the horizontal polarization phase (relative to the rf solenoid), which was controlled to within a one standard deviation range of $\sigma = 0.21$ rad. The minimum possible adjustment was 3.7 mHz out of a revolution frequency of 753 kHz, which changes the precession rate by 26 mrad/s. Such a capability meets a requirement for the use of storage rings to look for an intrinsic electric dipole moment of charged particles.

Published
2017
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17. Measurement of the Electron-Antineutrino Angular Correlation in Neutron β Decay

Author

B. Collett, W. A. Byron, G. Darius, Fred E. Wietfeldt, E. J. Stephenson, M. P. Mendenhall, Jeffrey S. Nico, M. T. Hassan, A. Komives, C. DeAngelis, Gordon L. Jones, Maynard S. Dewey, and H. Park

Subjects
Physics, Proton, 010308 nuclear & particles physics, media_common.quotation_subject, General Physics and Astronomy, Electron, 01 natural sciences, Asymmetry, Coincidence, Nuclear physics, Time of flight, Angular correlation, 0103 physical sciences, High Energy Physics::Experiment, Neutron, Nuclear Experiment, 010306 general physics, Electron neutrino, media_common
Abstract

We report the first result for the electron-antineutrino angular correlation (a coefficient) in free neutron β decay from the aCORN experiment. aCORN uses a novel method in which the a coefficient is proportional to an asymmetry in proton time of flight for events where the β electron and recoil proton are detected in delayed coincidence. Data are presented from a 15 month run at the NIST Center for Neutron Research. We obtained a=-0.1090±0.0030(stat)±0.0028(sys), the most precise measurement of the neutron a coefficient reported to date.

Published
2017

18. The connection between zero chromaticity and long in-plane polarization lifetime in a magnetic storage ring

Author

M. Gaisser, V. Shmakova, B. Lorentz, A. Nass, G. Guidoboni, S. Mey, D. Zyuzin, Frank Rathmann, R. Maier, E. J. Stephenson, A.K. Kacharava, F. Trinkel, Aleksandra Wrońska, P. Wüstner, D. Mchedlishvili, J. Bsaisou, G. Ciullo, M. Żurek, Y. Senichev, Paolo Lenisa, F. Hinder, Yuri F. Orlov, S. Dymov, Martin Rosenthal, N. Hempelmann, H. Stockhorst, P. Thörngren Engblom, D. Eversmann, P. Maanen, A. Saleev, Z. Bagdasarian, A. Pesce, Ralf Gebel, D. Prasuhn, P. Kulessa, J. Pretz, V. Hejny, H. Ströher, I. Keshelashvili, Y. Semertzidis, Andreas Lehrach, C. Weidemann, Yu. Valdau, S. Chekmenev, and R. Talman

Subjects
Physics and Astronomy (miscellaneous), Nuclear and High Energy Physics, Surfaces and Interfaces, Accelerator Physics (physics.acc-ph), Physics - Instrumentation and Detectors, Socio-culturale, FOS: Physical sciences, Ring (chemistry), 01 natural sciences, law.invention, law, 0103 physical sciences, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, ddc:530, Chromaticity, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment, Physics, 010308 nuclear & particles physics, Zero (complex analysis), Magnetic storage, Instrumentation and Detectors (physics.ins-det), Polarization (waves), Connection (mathematics), In plane, lcsh:QC770-798, Physics::Accelerator Physics, Physics - Accelerator Physics, Atomic physics
Abstract

In this paper, we demonstrate the connection between a magnetic storage ring with additional sextupole fields set so that the x and y chromaticities vanish and the maximizing of the lifetime of in-plane polarization (IPP) for a 0.97-GeV/c deuteron beam. The IPP magnitude was measured by continuously monitoring the down-up scattering asymmetry (sensitive to sideways polarization) in an in-beam, carbon-target polarimeter and unfolding the precession of the IPP due to the magnetic anomaly of the deuteron. The optimum operating conditions for a long IPP lifetime were made by scanning the field of the storage ring sextupole magnet families while observing the rate of IPP loss during storage of the beam. The beam was bunched and electron cooled. The IPP losses appear to arise from the change of the orbit circumference, and consequently the particle speed and spin tune, due to the transverse betatron oscillations of individual particles in the beam. The effects of these changes are canceled by an appropriate sextupole field setting., Comment: 18 pages, 18 figures, prepared for Phys. Rev. Accel. Beams

Published
2017
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19. A storage ring experiment to detect a proton electric dipole moment

Author

D. Kawall, Kyoko Makino, S. T. Park, Eric M. Metodiev, M. Bai, Andreas Lehrach, M. Grosse-Perdekamp, P. Fierlinger, A. Pesce, D. Moricciani, W. Meng, J. Talman, T. Roser, Andrew Ivanov, A.U. Luccio, Richard Talman, G. Venanzoni, M. Incagli, G. Guidoboni, J. Benante, Francois Méot, Konstantin Zioutas, Wolfram Fischer, Y. Giomataris, G. Fanourakis, Vadim Ptitsyn, S. Rescia, A. Sidorin, Jason Crnkovic, B. King, Michael Syphers, Selcuk Haciomeroglu, Richard Baartman, N. Tsoupas, B. I. Khazin, Yannis K. Semertzidis, Martin Berz, Yong-Ho Lee, Y. Senichev, G. Zavattini, Kevin Brown, J. Pretz, V. Tishchenko, T. J. V. Bowcock, S. K. Nayak, E. J. Stephenson, Ivan Koop, W.W. MacKay, Yuri F. Orlov, Alexey Lyapin, B. C. K. Casey, M. Blaskiewicz, C. Touramanis, A. N. Zelenski, R. Maier, M. Conte, Valeri Lebedev, G. Hoffstaetter, S. Baessler, E. Won, C. S. Özben, K. Vetter, Frank Rathmann, A. V. Fedotov, D. Raparia, A. Stahl, H. Huang, P. Pile, M. J. Lee, M. Gaisser, Shyh Yuan Lee, William J. Marciano, William Morse, B. Podobedov, D. M. Lazarus, P. Levi Sandri, Rasmus Larsen, Alexander J. Silenko, H. Kamal Sayed, Serge Andrianov, L. Miceli, N. Malitsky, P. Lenisa, Nikolaos Simos, H. Stroeher, S. Nagaitsev, S. Vlassis, Vassilis Anastassopoulos, E. J. Ramberg, Y. I. Kim, and V. Polychronakos

Subjects
Systematic error, Accelerator Physics (physics.acc-ph), Proton, Physics beyond the Standard Model, FOS: Physical sciences, p: electric moment, momentum, 01 natural sciences, High Energy Physics - Experiment, NO, Nuclear physics, Polarisation, Storage Rings, Fundamental Symmetries, Physics beyond Standard Model, High Energy Physics - Experiment (hep-ex), 0103 physical sciences, ddc:530, 010306 general physics, Instrumentation, Fundamental Symmetries, Polarisation, Physics, polarization, 010308 nuclear & particles physics, new physics, Magic (programming), Physics beyond Standard Model, storage ring, sensitivity, Electric dipole moment, electric moment [p], Storage Rings, Physics - Accelerator Physics, Storage ring, dipole, experimental results
Abstract

A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of $10^{-29}e\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000~TeV., Comment: 8 pages, 3 figures

Published
2016
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20. New method for a continuous determination of the spin tune in storage rings and implications for precision experiments

Author

V. Hejny, H. Glückler, S. Chekmenev, Susanna Bertelli, Martin Berz, D. Mchedlishvili, Serge Andrianov, B. Lorentz, K. Grigoryev, Y. Semertzidis, G. Natour, B. Mariański, G.G. Macharashvili, K. Nowakowski, M. Zakrzewska, M. Contalbrigo, I. Keshelashvili, Paolo Lenisa, R. Talman, Frank Rathmann, E. Valetov, M. S. Nioradze, M. Statera, S. Dymov, A. Trzciński, D. Chiladze, Hans-Joachim Krause, J. Ritman, Andreas Lehrach, A. Saleev, Nikolai N. Nikolaev, H. Stockhorst, D. Hölscher, F. Hinder, V. Shmakova, S. Mey, C. Hanhart, C. Weidemann, J. Slim, A. Vassiliev, Ivan Koop, A. Khoukaz, Frank Goldenbaum, P. Zupranski, M. Bai, D. Eversmann, P. Maanen, M. D. Tabidze, M. Gaisser, N. Hempelmann, N.L. Lomidze, Alexander J. Silenko, A. Magiera, H. Straatmann, Dirk Heberling, R. Engels, D. Prasuhn, Andreas Nogga, W. Augustyniak, Z. Bagdasarian, J. Pretz, J. de Vries, A. Pesce, S. Krewald, D. Zyuzin, F. Trinkel, Ralf Gebel, A. Nass, Andrew Ivanov, G. Guidoboni, V. Kamerdzhiev, Kyoko Makino, Zbigniew Rudy, Colin Wilkin, Yu. Valdau, Ulf-G. Meißner, B. Kamys, P. Wüstner, Y. Senichev, Y. u. Uzikov, F.M. Esser, Andreas Wirzba, E. J. Stephenson, Aleksandra Wrońska, Olaf Felden, A.K. Kacharava, Rolf Stassen, G. Ciullo, P. Thörngren Engblom, R. Hipple, Rudolf Maier, J. Bsaisou, J. Hetzel, Achim Stahl, H. Soltner, H. Ströher, A. I. Kulikov, Werner Bernreuther, D. Grzonka, and Martin Rosenthal

Subjects
Accelerator Physics (physics.acc-ph), time reversal, Cyclotron, FOS: Physical sciences, General Physics and Astronomy, Socio-culturale, Electron, 01 natural sciences, 7. Clean energy, law.invention, Nuclear physics, Economica, law, 0103 physical sciences, ddc:550, Nuclear Experiment (nucl-ex), 010306 general physics, and other discrete symmetries, 11.30.Er Charge conjugation, Nuclear Experiment, Spin-½, Accelerator physics, Physics, Spin polarization, 010308 nuclear & particles physics, Charged particle, Dipole, parity, 29.20.dg Cyclotrons, 11.30.Er Charge conjugation, parity, time reversal, and other discrete symmetries,13.40.Em Electric and magnetic moments, 13.40.Em Electric and magnetic moments, Physics - Accelerator Physics, Atomic physics, 29.20.dg Cyclotrons, Storage ring
Abstract

A new method to determine the spin tune is described and tested. In an ideal planar magnetic ring, the spin tune - defined as the number of spin precessions per turn - is given by $\nu_s = \gamma G$ (gamma is the Lorentz factor, $G$ the magnetic anomaly). For 970 MeV/c deuterons coherently precessing with a frequency of ~120 kHz in the Cooler Synchrotron COSY, the spin tune is deduced from the up-down asymmetry of deuteron carbon scattering. In a time interval of 2.6 s, the spin tune was determined with a precision of the order $10^{-8}$, and to $1 \cdot 10^{-10}$ for a continuous 100 s accelerator cycle. This renders the presented method a new precision tool for accelerator physics: controlling the spin motion of particles to high precision is mandatory, in particular, for the measurement of electric dipole moments of charged particles in a storage ring., Comment: 6 pages, 6 figures

Published
2015
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21. Measurement of the analyzing power AN in pp elastic scattering in the CNI region with a polarized atomic hydrogen gas jet target

Author

T. Wise, A. Nass, W. Haeberli, R. L. Gill, Satish Dhawan, O. Jinnouchi, G. Bunce, E. J. Stephenson, I. G. Alekseev, Alexander Khodinov, A. N. Zelenski, A. Bravar, Y. I. Makdisi, Hiroyuki Okada, Norio Saito, and D. N. Svirida

Subjects
Physics, Elastic scattering, Nuclear and High Energy Physics, Jet (fluid), Proton, 010308 nuclear & particles physics, media_common.quotation_subject, Momentum transfer, Hadron, 01 natural sciences, Asymmetry, Nuclear physics, Amplitude, 0103 physical sciences, High Energy Physics::Experiment, Spin-flip, Nuclear Experiment, 010306 general physics, media_common
Abstract

A precise measurement of the analyzing power A N in proton–proton elastic scattering in the region of 4-momentum transfer squared 0.001 | t | 0.032 ( GeV / c ) 2 has been performed using a polarized atomic hydrogen gas jet target and the 100 GeV/ c RHIC proton beam. The interference of the electromagnetic spin-flip amplitude with a hadronic spin-nonflip amplitude is predicted to generate a significant A N of 4–5%, peaking at − t ≃ 0.003 ( GeV / c ) 2 . This kinematic region is known as the Coulomb nuclear interference region. A possible hadronic spin-flip amplitude modifies this calculable prediction. We present the first precise result of the CNI asymmetry and shape as a function of t . Our data are well described by the CNI prediction with the electromagnetic spin-flip alone and do not support the presence of a large hadronic spin-flip amplitude.

Published
2006
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22. An update from STAR—using strangeness to probe relativistic heavy ion collisions

Author

V. V. Belaga, V. Grigoriev, Z. Xu, Sergey Voloshin, P. Sorensen, R. L. Ray, E. Potrebenikova, M.A. Kramer, R. V. Cadman, Peter Graham Jones, K. J. Foley, F. Laue, A. Szanto de Toledo, T. Ljubicic, Jianhong Wu, H. Caines, E. Sugarbaker, T. Pawlak, V. L. Rykov, Frank Jm Geurts, L. Didenko, G. Eppley, J. Porter, I. Sakrejda, J. Balewski, J. Baudot, Claude Andre Pruneau, J. Pluta, R. Willson, D. G. Underwood, F. Meissner, A. Stolpovsky, R. Lednický, V. A. Nikitin, T. Ullrich, Y. V. Zanevski, R. Zoulkarneev, L. Kotchenda, S. Kabana, K. E. Shestermanov, Jinghui Yang, A. Lebedev, Q. J. Liu, M. M. de Moura, K. Schweda, T. J. Hallman, T. J. M. Symons, S. V. Razin, L. Gaudichet, J. Kiryluk, M. L. Miller, B. Choi, R. E. Tribble, R. S. Longacre, H. Bichsel, M. Castro, Jay Roberts, S. R. Klein, C. Struck, O. Barannikova, D. L. Olson, Gerald W Hoffmann, Yu-Gang Ma, A. Tai, P. Szarwas, J. Takahashi, J. Putschke, G. Odyniec, D. Thein, Alexander Kovalenko, O. A. Grachov, X. Dong, C. L. Kunz, C. F. Moore, J. W. Watson, A. Bravar, Joseph Adams, A. A. Derevschikov, L. V. Nogach, A. H. Tang, R.Kh. Kutuev, J. Berger, S. P. Chernenko, A. Ogawa, M. Kopytine, J. Amonett, W. J. Llope, X. L. Wang, Julien Faivre, J. Klay, V. B. Dunin, A. V. Brandin, Zhongyukun Xu, Thomas A. Trainor, A. Ridiger, Thorsten Sven Kollegger, D. Reichhold, D. Magestro, L. Ruan, V. Trofimov, M. Tokarev, A. Rose, V. Emelianov, A. I. Pavlinov, D. Keane, T. J. Humanic, R. Witt, F. Liu, M. B. Tonjes, S. Heppelmann, D. Flierl, Matthew J. Anderson, Marie Germain, R. P. Scharenberg, S. M. Guertin, S L Huang, Alexandre Alarcon Do Passo Suaide, B. Lasiuk, J. H. Thomas, H. S. Matis, L. Martin, David Lynn, H. Long, Nikolai Smirnov, R. Stock, J. Mitchell, L. G. Efimov, G. Skoro, S. E. Vigdor, G. Igo, J. Zoulkarneeva, Christian Claude Kuhn, V. Morozov, I.A. Savin, W. W. Jacobs, D. D. Koetke, V. Petrov, J. E. Draper, A. N. Zubarev, C. A. Gagliardi, E. Hjort, B. E. Bonner, J. Lauret, B. D. Anderson, O. D. Tsai, D. Hardtke, J. Fu, B. K. Srivastava, Yu Chen, R. D. Majka, N. T. Porile, M. Messer, M.M. Corral, G. S. Averichev, H. H. Wieman, J. Sowinski, S. Stanislaus, J. Marx, Z. M. Wang, M. A. Vasiliev, T. Herston, B. Surrow, S. Margetis, J. Schambach, P. Fachini, J. P. Coffin, O. V. Rogachevski, J. Gans, Boris Hippolyte, H. Ward, W. Christie, J. C. Dunlop, A. I. Kulikov, R. Manweiler, J. Carroll, P. Seyboth, Masashi Kaneta, Fuqiang Wang, H. M. Spinka, Sevil Salur, M. Oldenburg, T. Dietel, W. M. Zhang, Andrey Vasiliev, A. M. Poskanzer, Zubayer Ahammed, J. G. Ma, Y. Panebratsev, M. Shao, M. J. LeVine, V. Ghazikhanian, D. Grosnick, S. Lange, G. Rai, Janet Elizabeth Seger, A. A. Kuznetsov, V. I. Yurevich, J. L. Romero, C. P. Lansdell, Yu A. Matulenko, Frank Simon, S.J. Lindenbaum, L. S. Schroeder, E. Yamamoto, E. Finch, T W Henry, I. Zborovský, R.J.M. Snellings, B. Erazmus, R. Wells, A. P. Meschanin, M. Heinz, Lee Stuart Barnby, F. Retiere, Y. Fisyak, M. Horsley, C Whitten, Ian Johnson, N. G. Minaev, N. Xu, P. Filip, C Li, B. Stringfellow, D. Cebra, N. Schmitz, G. D. Westfall, E. Shahaliev, S. Trentalange, W. A. Love, Malgorzata Anna Janik, Yu Melnick, Marcelo Gameiro Munhoz, D. J. Prindle, H. Zhang, E. J. Stephenson, M. A. Lisa, A. Billmeier, J. G. Cramer, R. Fatemi, K. Krueger, M. Cherney, Thomas Michael Cormier, T. S. McShane, P. Nevski, J. E. Gonzalez, M. Lopez-Noriega, Adam Ryszard Kisiel, Michal Sumbera, H. J. Crawford, A. Ishihara, G. Renault, J. Engelage, C. Suire, V. Faine, John N. Wood, J. Castillo, S. W. Wissink, J. M. Landgraf, V. A. Okorokov, M. Strikhanov, G. Rakness, M. Guedon, A. M. VanderMolen, Guy Paic, E. G. Judd, A. Chikanian, S. S. Shimanskii, P.A. Zolnierczuk, Christina Markert, J. Sandweiss, Z. Liu, A. Boucham, D. Arkhipkin, S. Bekele, C. Roy, C. O. Blyth, A. Klyachko, Vladimir Tikhomirov, P. Chaloupka, B. Norman, G. Van Buren, T. W. Ludlam, J. M. Nelson, W. Peryt, H. G. Ritter, H. Z. Huang, Morton Kaplan, X. Z. Cai, R. Bellwied, A. S. Konstantinov, L. C. Bland, L. Liu, V. M. Leontiev, D. Seliverstov, A. Schüttauf, Olivier Ravel, A. S. Hirsch, Peter Martin Jacobs, P. Kravtsov, C. Adler, M. A. C. Lamont, S. B. Nurushev, Z. Milosevich, Jeffrey G. Reid, Hao-Ze Chen, M. Calderon De La Barca Sanchez, Subhasis Chattopadhyay, Q. Li, J. W. Harris, N.D. Gagunashvili, A Cardenas, Z P Zhang, E. Gushin, G. J. Kunde, P. Yepes, V. Eckardt, V. Perevoztchikov, K. Filimonov, Sergey Panitkin, S. U. Pandey, and A. E. Yakutin

Subjects
Nuclear reaction, Physics, Nuclear and High Energy Physics, Particle physics, Strange quark, media_common.quotation_subject, Hadron, Elementary particle, Kinematics, Decoupling (cosmology), Strangeness, Asymmetry, Nuclear physics, Nuclear Experiment, media_common
Abstract

An overview of the strangeness measurements made by the STAR collaboration at RHIC for Au-Au collisions at √s NN = 130 and 200 GeV plus p-p collisions at √s NN = 200 GeV is presented. A wealth of information has been generated on the kinematics and scale of strange particle production by this experiment. When viewed in combination a picture emerges of particles demonstrating a surprisingly high degree of collective motion, suggestive of strong internal pressure within the source which builds up rapidly. The non-resonance yields are consistent with statistical hadron formation. Although there appears to be a rapid decoupling of the source, resonance particle measurements show signs of rescattering during the hadronic phase. Meanwhile the observed suppression of high momentum probes and their large azimuthal asymmetry indicate that this hot dense matter has significant interactions with particles moving through it.

Published
2003
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23. Strange antiparticle-to-particle ratios at mid-rapidity in =130 GeV Au+Au collisions

Author

M. Calderon De La Barca Sanchez, A. Lebedev, R. V. Cadman, Vitaly Okorokov, Frank Jm Geurts, Q. Li, Adam Ryszard Kisiel, T. J. Humanic, H. J. Crawford, I.A. Savin, N. T. Porile, R. Fatemi, Y. Panebratsev, V. Trofimov, C. A. Gagliardi, Q. J. Liu, C. A. Whitten, K. Krueger, G. Rai, Yu A. Matulenko, T. Herston, Fuqiang Wang, C. E. Allgower, M. Horsley, B. Stringfellow, S. Lange, S. J. Lindenbaum, N. Xu, J. Balewski, M. Cherney, H. G. Ritter, Thomas Michael Cormier, Claude Andre Pruneau, W. Christie, G. D. Westfall, A. Billmeier, P. Nevski, J. W. Harris, Malgorzata Anna Janik, V. I. Yurevich, C. Struck, J. Takahashi, J. Putschke, J. W. Watson, A. I. Kulikov, A. Ridiger, Thorsten Sven Kollegger, J. G. Cramer, K. Schweda, T. Ullrich, J. H. Thomas, A. S. Hirsch, Frank Simon, C. Roy, P. Kravtsov, Masashi Kaneta, A. M. Poskanzer, A. Ogawa, R. Bellwied, Thomas A. Trainor, E. Yamamoto, C. Adler, R. Zoulkarneev, A. Stolpovsky, L. Kotchenda, B. Erazmus, A. S. Konstantinov, A. Tai, R. S. Longacre, W. M. Zhang, Andrey Vasiliev, R. Lednický, V. A. Nikitin, Joseph Adams, J. Amonett, V. Grigoriev, T. Dietel, K. E. Shestermanov, R. L. Ray, M. Kramer, A. Klyachko, E. Potrebenikova, M. Heinz, Lee Stuart Barnby, J. Klay, E. Gushin, G. J. Kunde, M. Castro, M. Oldenburg, P. Yepes, V. Eckardt, E. Hjort, D. Magestro, B. Choi, Jeffrey G. Reid, D. Cebra, T. S. McShane, V. Emelianov, Vladimir Tikhomirov, D. Keane, S. Heppelmann, D. Flierl, A. H. Tang, F. Retiere, T. Ljubicic, Nikolai Smirnov, Yu Melnick, N. G. Minaev, Z. J. Xu, R. Stock, J. Mitchell, H. Caines, W. A. Love, L. G. Efimov, Marcelo Gameiro Munhoz, Alexander Kovalenko, L. V. Nogach, Vladimir Petrov, R. P. Scharenberg, S. P. Chernenko, Yu. Ivanshin, V. L. Rykov, Janet Elizabeth Seger, D. J. Prindle, W. J. Llope, G. S. Averichev, L. Martin, H. Zhang, J. Carroll, S. Trentalange, Guy Paic, A. Chikanian, S. S. Shimanskii, G. Igo, E. J. Stephenson, J. N. Marx, B. E. Bonner, Marie Germain, A. Cardenas, O. D. Tsai, H. S. Matis, G. Skoro, G. Rakness, W. W. Jacobs, B. D. Anderson, M. A. Lisa, A. A.P. Suaide, S. M. Guertin, J. E. Draper, Julien Faivre, A. Rose, J. Lauret, L. C. Bland, A. Boucham, B. Lasiuk, V. Ghazikhanian, A. V. Brandin, H. Bichsel, Yu Chen, W. S. Deng, H. Ward, V. Perevoztchikov, G. Odyniec, K. Filimonov, David Lynn, S. E. Vigdor, Christian Claude Kuhn, A. A. Kuznetsov, L. Liu, V. M. Leontiev, Olivier Ravel, Sergey Panitkin, M. Planinic, S. Bekele, J. P. Coffin, O. V. Rogachevski, D. Reichhold, A. I. Pavlinov, F. Liu, M. B. Tonjes, G. Eppley, Subhasis Chattopadhyay, E. G. Judd, A. N. Zubarev, Matthew J. Anderson, E. Sugarbaker, H. Z. Huang, J. Pluta, J. L. Romero, E. Finch, A. Ishihara, V. Morozov, M. Messer, Sevil Salur, Morton Kaplan, S. Margetis, O. A. Grachov, J. G. Ma, B. Surrow, S. U. Pandey, F. Meissner, A. E. Yakutin, C. P. Lansdell, R. Wells, R.J.M. Snellings, P. Seyboth, D. Hardtke, R. D. Majka, Sergey Voloshin, K. J. Foley, G. Van Buren, A. P. Meschanin, N.D. Gagunashvili, A. Bravar, J. Sowinski, R. K. Kutuev, P. Fachini, R. E. Tribble, J. Schambach, Gerald W Hoffmann, H. M. Spinka, T. W. Ludlam, T. W. Henry, J. Baudot, I. Sakrejda, J. M. Nelson, Y. V. Zanevski, N. Schmitz, E. Shahaliev, I. Zborovský, W. Peryt, M. Lopez-Noriega, M. M. de Moura, Y. Fisyak, Ian Johnson, M. L. Miller, D. Seliverstov, A. Schüttauf, M. Guedon, A. M. VanderMolen, Michael A. Thompson, P. Szarwas, V. V. Belaga, Peter Martin Jacobs, Michal Sumbera, G. Renault, M. A. C. Lamont, S. B. Nurushev, Z. Milosevich, C. Suire, P. Chaloupka, V. Faine, J. Castillo, P. Sorensen, S. W. Wissink, Peter Graham Jones, L. Didenko, Jinghui Yang, S. R. Klein, O. Barannikova, D. L. Olson, A. A. Derevschikov, D. Thein, H. Long, M. Kopytine, M. Tokarev, M.M. Corral, H. H. Wieman, S. V. Razin, L. Gaudichet, J. Kiryluk, Jay Roberts, C. L. Kunz, F. Laue, A. Szanto de Toledo, C. F. Moore, T. Pawlak, J. C. Dunlop, J. Porter, Zubayer Ahammed, M. J. LeVine, R. Willson, D. G. Underwood, L. S. Schroeder, R. Witt, J. Fu, B. K. Srivastava, I. M. Vasilevski, T. J. Hallman, J. Gans, T. J. M. Symons, Boris Hippolyte, J. Berger, V. B. Dunin, C. O. Blyth, B. Norman, J. Engelage, John N. Wood, J. M. Landgraf, M. Strikhanov, Christina Markert, J. Sandweiss, and Z. Liu

Subjects
Quark, Physics, Nuclear and High Energy Physics, Strange quark, Antiparticle, Particle physics, STAR, Hyperon, Strangeness, Baryochemical potential, Nuclear physics, Baryon, Relativistic heavy-ion collisions, Antibaryon-to-baryon ratios, Rapidity, Nucleon
Abstract

Values of the ratios in the mid-rapidity yields of Λ / Λ =0.71±0.01( stat. )±0.04( sys. ) , Ξ + / Ξ − =0.83±0.04( stat. )±0.05( sys. ) , Ω + / Ω − =0.95±0.15( stat. )±0.05( sys. ) and K + /K − =1.092±0.023(combined) were obtained in central s NN =130 GeV Au+Au collisions using the STAR detector. The ratios indicate that a fraction of the net-baryon number from the initial system is present in the excess of hyperons over antihyperons at mid-rapidity. The trend in the progression of the baryon ratios, with increasing strange quark content, is similar to that observed in heavy-ion collisions at lower energies. The value of these ratios may be related to the charged kaon ratio in the framework of simple quark-counting and thermal models.

Published
2003
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24. Strangeness in Au$plus$Au collisions at $\surd$sNN $equal$ 130 GeV observed with the STAR detector

Author

Y. Fisyak, A. Ogawa, Ian Johnson, Christophe Pierre Suire, A. H. Tang, P. Seyboth, Guy Paic, A. Chikanian, S. S. Shimanskii, A. Ridiger, K. Schweda, G. Eppley, A. Stolpovsky, H. Hümmler, Marie Germain, T. S. McShane, M. Šumbera, J. Pluta, V. Ghazikhanian, R. S. Longacre, Michael A. Thompson, L. Kotchenda, C. Struck, A. A.P. Suaide, S. Heppelmann, D. Flierl, A. I. Pavlinov, B. E. Bonner, J. L. Romero, O. D. Tsai, L. Lakehal-Ayat, G. Van Buren, J. Takahashi, J. W. Watson, L. Martin, F. Liu, M. B. Tonjes, A. N. Zubarev, G. Igo, A. Boucham, R. E. Tribble, Gerald W Hoffmann, S. Lee Barnby, M. Castro, Torre Wenaus, R. K. Kutuev, V. Morozov, M. Messer, V. Grigoriev, Q. Li, J. Grabski, K. Krueger, V. S. Shvetcov, Q. J. Liu, C. A. Whitten, Thomas A. Trainor, J. Berger, J. E. Draper, V. Faine, R. L. Ray, J. Castillo, E. Potrebenikova, J. M. Nelson, D. Hardtke, P. Fachini, A. M. van der Molen, S. Bekele, W. Peryt, R. D. Majka, R. V. Cadman, S. W. Wissink, E. Finch, Frank Jm Geurts, B. Choi, B. D. Anderson, J. N. Marx, A. P. Meschanin, C. E. Allgower, V. V. Belaga, J. Fu, B. K. Srivastava, I. M. Vasilevski, Alexander Kovalenko, J. Sowinski, J. Schambach, T. Ljubicic, H. Caines, W. S. Deng, J. P. Coffin, O. V. Rogachevski, V. Perevoztchikov, K. Filimonov, L. V. Nogach, V. L. Rykov, M. Cherney, A. Ishihara, V. B. Dunin, W. Christie, J. Gans, P. Sorensen, S. Lange, E. Sugarbaker, Thomas Michael Cormier, V. Trofimov, Peter Graham Jones, A. I. Kulikov, S. J. Lindenbaum, Yu Chen, H. Z. Huang, Boris Hippolyte, Masashi Kaneta, R. Wells, Morton Kaplan, W. M. Zhang, Andrey Vasiliev, J. Balewski, J. G. Cramer, P. Nevski, Sergey Panitkin, J. C. Dunlop, Claude Andre Pruneau, Sergey Voloshin, L. Didenko, F. Meissner, D. Seliverstov, A. Schüttauf, Jinghui Yang, T. Ullrich, G. lo Curto, Janet Elizabeth Seger, R. Zoulkarneev, K. J. Foley, L. C. Bland, Peter Martin Jacobs, Subhasis Chattopadhyay, Zubayer Ahammed, M. Kramer, K. Turner, M. Guedon, M. J. LeVine, S. Radomski, S. R. Klein, Y. Panebratsev, T. J. Humanic, C. Roy, S. U. Pandey, A. E. Yakutin, O. Barannikova, D. L. Olson, I.A. Savin, N. T. Porile, J. W. Harris, R. P. Scharenberg, G. Rai, M. A. C. Lamont, S. B. Nurushev, Z. Milosevich, Mingshui Chen, F. Retiere, A. Klyachko, A. A. Derevschikov, A. Lebedev, S. Margetis, N. Schmitz, H. S. Matis, A. C. Saulys, F. Laue, Yu A. Matulenko, M. Horsley, E. Gushin, G. J. Kunde, Vladimir Tikhomirov, N. G. Minaev, Vladimir Petrov, E. Shahaliev, P. Yepes, V. Eckardt, O. A. Grachov, A. Szanto de Toledo, B. Stringfellow, Z. J. Xu, S. P. Chernenko, L. S. Schroeder, E. G. Judd, Adam Ryszard Kisiel, N. Xu, W. J. Llope, S. Trentalange, J. Baudot, S. V. Razin, E. Hjort, L. Gaudichet, H. J. Crawford, A. Cardenas, J. Kiryluk, N.D. Gagunashvili, Y. V. Zanevski, T. Pawlak, G. D. Westfall, J. Carroll, W. W. Jacobs, Jay Roberts, Malgorzata Anna Janik, J. Porter, B. Lasiuk, C. L. Kunz, M. Lopez-Noriega, H. Long, C. F. Moore, C. P. Lansdell, R.J.M. Snellings, R. Witt, R. Willson, A. Tai, D. G. Underwood, J. Amonett, G. Skoro, M. Heffner, J. Klay, M. Oldenburg, V. Emelianov, D. Keane, D. Reichhold, R. Lednický, Nikolai Smirnov, R. Stock, J. Mitchell, L. G. Efimov, T. J. Hallman, T. J. M. Symons, Yu. Ivanshin, V. A. Nikitin, H. Ward, A. S. Hirsch, M. de la Calderón Barca Sánchez, A. A. Kuznetsov, L. Liu, P. Kravtsov, V. M. Leontiev, Olivier Ravel, C. Adler, K. E. Shestermanov, H. G. Ritter, R. Bellwied, Jeffrey G. Reid, A. S. Konstantinov, B. Erazmus, D. Cebra, Yu Melnick, V. A. Moiseenko, Marcelo Gameiro Munhoz, D. J. Prindle, A. V. Brandin, H. Zhang, E. J. Stephenson, M. A. Lisa, H. M. Spinka, J. H. Thomas, H. Bichsel, S. E. Vigdor, G. Odyniec, G. S. Averichev, Christian Claude Kuhn, Matthew J. Anderson, David Lynn, Lee Stuart Barnby, C. O. Blyth, A. M. Poskanzer, W. A. Love, B. Norman, I. Sakrejda, Vitaly Okorokov, M. Tokarev, H. H. Wieman, J. Engelage, John N. Wood, J. M. Landgraf, M. M. de Moura, M. Strikhanov, M. L. Miller, Christina Markert, J. Sandweiss, Z. Liu, P. Szarwas, E. Yamamoto, C. A. Gagliardi, T. Herston, Fuqiang Wang, V. I. Yurevich, and I. Zborovský

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Phenomenology, Nuclear Theory, Hadron, Strangeness production, Astrophysics::Cosmology and Extragalactic Astrophysics, Strangeness, Spectral line, Nuclear physics, Baryon, Transverse plane, Pion, High Energy Physics::Experiment, Nuclear Experiment, STAR detector
Abstract

The STAR detector has made a variety of measurements of strange and other hadronic species in Au+Au collisions at s N N = 130 GeV. A comparison of kaon and pion production enables an examination of the systematics of strangeness production with energy by comparing them to lower energy collisions. Anti-baryon to baryon ratios indicate a much reduced net-baryon density and transverse momentum spectra show that a picture of transverse expansion seems appropriate.

Published
2002
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25. Isospin Symmetry in the Structure Study of Unstable Nuclei

Author

E. J. Stephenson, Tetsuo Noro, A.D. Bacher, Hideki Ueno, T. Black, C. C. Foster, Hisanori Fujita, K. Katori, H. Fujimura, G. P. A. Berg, Y. Shimbara, M. Yosoi, D. A. Roberts, W.R. Lozowski, Takahiro Kawabata, T. Yamanaka, Y. Fujita, J. W. Jänecke, Kichiji Hatanaka, Junichiro Kamiya, and K. Hara

Subjects
Physics, Physics and Astronomy (miscellaneous), Structure (category theory), Symmetry (physics), Good quantum number, medicine.anatomical_structure, Classical mechanics, Nucleosynthesis, Isospin, Excited state, medicine, Mirror nuclei, Atomic physics, Nucleus
Abstract

Assuming isospin T is a good quantum number, the analog states of the low-lying states in T z = ′ (T 0 +1) nuclei can be found as excited T 0 +1 states in T z = ′T 0 nuclei. Therefore, if To + 1 states are identified in theexcited region of T z = ′T 0 nuclei, the structure of unstable nuclei with T z = ′(T 0 + 1) can be deduced. We measured and compared the transition strengths to pairs of excited analog states in inelastic and charge-exchange reactions on the same target nucleus. The T values of these analog states were identified by using the fact that the transition strengths to them are different depending on T. The identification of T = ½ and 3/2 nature of analog M1 and GT states in the mirror nuclei pair 2 7 Al and 2 7 Si is reported by comparing the transition strengths in high-resolution 2 7 Al(p,p') and 2 7 Al( 3 He, t) 2 7 Si reactions at 0°. The identified T = 3/2 states are analogous to the low-lying states of 2 7 Mg, which plays an important role in rp-process of nucleosynthesis.

Published
2002
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26. Measuring the polarization of a rapidly precessing deuteron beam

Author

P. Lenisa, Z. Bagdasarian, A. Pesce, Ralf Gebel, B. Lorentz, P. Thörngren Engblom, J. Dietrich, Hans Stockhorst, Frank Rathmann, V. Hejny, R. Maier, S. Bertelli, E. J. Stephenson, L. Magallanes, V. Kamerdzhiev, Yu. Valdau, G. Fanourakis, H. Ströher, C. Weidemann, A. Nass, V. Shmakova, B. Gou, Richard Talman, D. Chiladze, Andreas Lehrach, D. Eversmann, G. Ciullo, M. Gaisser, D. Mchedlishvili, William Morse, S. Dymov, P. Wüstner, D. Oellers, G. Guidoboni, Yannis K. Semertzidis, D. Prasuhn, A.K. Kacharava, and J. Pretz

Subjects
Accelerator Physics (physics.acc-ph), Physics, 29.20.D- Cyclic accelerators and storage rings, 29.27.Hj Polarized beams, 29.27.Ac Beam injection and extraction, Nuclear and High Energy Physics, Polarization rotator, Physics and Astronomy (miscellaneous), Spin polarization, Linear polarization, business.industry, FOS: Physical sciences, Surfaces and Interfaces, Polarization (waves), Electric dipole moment, Optics, Precession, Radial polarization, lcsh:QC770-798, Physics - Accelerator Physics, ddc:530, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, business, Storage ring
Abstract

This paper describes a time-marking system that enables a measurement of the in-plane (horizontal) polarization of a 0.97-GeV/c deuteron beam circulating in the Cooler Synchrotron (COSY) at the Forschungszentrum J\"ulich. The clock time of each polarimeter event is used to unfold the 120-kHz spin precession and assign events to bins according to the direction of the horizontal polarization. After accumulation for one or more seconds, the down-up scattering asymmetry can be calculated for each direction and matched to a sinusoidal function whose magnitude is proportional to the horizontal polarization. This requires prior knowledge of the spin tune or polarization precession rate. An initial estimate is refined by re-sorting the events as the spin tune is adjusted across a narrow range and searching for the maximum polarization magnitude. The result is biased toward polarization values that are too large, in part because of statistical fluctuations but also because sinusoidal fits to even random data will produce sizeable magnitudes when the phase is left free to vary. An analysis procedure is described that matches the time dependence of the horizontal polarization to templates based on emittance-driven polarization loss while correcting for the positive bias. This information will be used to study ways to extend the horizontal polarization lifetime by correcting spin tune spread using ring sextupole fields and thereby to support the feasibility of searching for an intrinsic electric dipole moment using polarized beams in a storage ring. This paper is a combined effort of the Storage Ring EDM Collaboration and the JEDI Collaboration., Comment: 28 pages, 15 figures, prepared for Physical Review ST - Accelerators and Beams

Published
2014
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27. Midrapidity Antiproton-to-Proton Ratio fromAu+AuCollisions atsNN=130GeV

Author

Sergey Voloshin, J. Engelage, K. J. Foley, R. S. Longacre, J. M. Landgraf, M. Strikhanov, N. Xu, C. Roy, J. Sandweiss, G. D. Westfall, J. Baudot, B. Erazmus, J. Castillo, Y. V. Zanevski, Malgorzata Anna Janik, G. Igo, J. Carroll, D. M. Moltz, S. W. Wissink, A. A. Kuznetsov, C. O. Blyth, B. Norman, A. Klyachko, A. Maliszewski, H. M. Spinka, V. M. Leontiev, Olivier Ravel, R. Wells, V. A. Nikitin, K. Turner, T. Ullrich, D.E. Greiner, A. C. Saulys, K. E. Shestermanov, D. Cebra, Y. Fisyak, P. Fachini, A. Ogawa, Ian Johnson, V. S. Shvetcov, C. A. Whitten, Z. Z. Xu, T. J.M. Symons, E. Platner, A. Stolpovsky, H. Hümmler, W. Pinganaud, Jay Roberts, P. Leszczynski, S. Lange, T. Herston, S. J. Lindenbaum, Adam Ryszard Kisiel, P. Seyboth, Lee Stuart Barnby, Yu Melnick, L. Kotchenda, W. Christie, Vladimir Tikhomirov, S. Y. Panitkin, R. Bossingham, M. Lopez-Noriega, H. J. Crawford, J. G. Cramer, C. L. Kunz, B. Choi, A. Szanto de Toledo, C. F. Moore, H. G. Ritter, M. Castro, J. Lamas-Valverde, N. Schmitz, A. I. Kulikov, Matthew J. Anderson, R. Bellwied, A. S. Konstantinov, H. Bichsel, G. Odyniec, V. Trofimov, A. P. Meschanin, K. Krueger, Alexander Kovalenko, L. V. Nogach, R. Witt, E. Yamamoto, J. H. Thomas, L. Conin, G. Skoro, A. A.P. Suaide, Christophe Pierre Suire, Masashi Kaneta, M. Heffner, W. M. Zhang, Andrey Vasiliev, J. C. Dunlop, S. Radomski, S. Trentalange, C. E. Allgower, Zubayer Ahammed, V. Ghazikhanian, M. J. LeVine, A. H. Tang, W. A. Love, Joakim Nystrand, M. Cherney, John Z. H. Zhang, Thomas Michael Cormier, Vladimir Petrov, E. G. Judd, P. Nevski, T. Pawlak, David Lynn, L. Madansky, M. Kramer, G. S. Averichev, S. P. Chernenko, W. J. Llope, T. S. McShane, I. Sakrejda, E. Sugarbaker, A. Cardenas, Janet Elizabeth Seger, H. Z. Huang, D. Russ, Yu Chen, Fuqiang Wang, G. S. Mutchler, C. P. Lansdell, R.J.M. Snellings, J. Porter, L. S. Schroeder, Guy Paic, A. Chikanian, S. S. Shimanskii, J. Mitchell, B. Lasiuk, J. Grabski, A. I. Pavlinov, H. Long, Frank Jm Geurts, M. B. Tonjes, V. Morozov, P. Szarwas, V. I. Yurevich, J. N. Marx, D. Hardtke, F. Laue, R. D. Majka, A. V. Brandin, J. Sowinski, B. K. Srivastava, I. M. Vasilevski, J. Berger, J. Gans, E. Finch, Boris Hippolyte, S. E. Vigdor, V. A. Moiseenko, T. J. Humanic, Christian Claude Kuhn, A. Boucham, Marcelo Gameiro Munhoz, D. J. Prindle, I.A. Savin, N. T. Porile, V. B. Dunin, S. Bekele, E. J. Stephenson, M. A. Lisa, Yu A. Matulenko, M. Horsley, B. Stringfellow, A. Ishihara, R. Willson, D. G. Underwood, A. M. VanderMolen, D. Reichhold, T. J. Hallman, A. M. Poskanzer, A. Vanyashin, M. Tokarev, H. H. Wieman, A. S. Hirsch, P. Kravtsov, C. Adler, C. Struck, J. Takahashi, A. Ridiger, Torre Wenaus, Jeffrey G. Reid, Thomas A. Trainor, Morton Kaplan, R. P. Scharenberg, H. S. Matis, C. A. Ogilvie, W. W. Jacobs, D. Seliverstov, A. Schüttauf, Subhasis Chattopadhyay, Peter Martin Jacobs, S. Heppelmann, S. V. Razin, D. Flierl, H. Ward, M. A. C. Lamont, S. B. Nurushev, Z. Milosevich, L. Martin, G. Van Buren, R. K. Kutuev, J. M. Nelson, H. Stroebele, W. Peryt, J. E. Draper, N.D. Gagunashvili, J. P. Coffin, O. V. Rogachevski, V. Perevoztchikov, Alexander Khodinov, L. C. Bland, S. U. Pandey, A. E. Yakutin, J. W. Harris, E. Gushin, G. J. Kunde, P. Yepes, V. Eckardt, A. Yokosawa, G. Eppley, J. Pluta, Q. Li, Gerald W Hoffmann, Mingshui Chen, Thomas LeCompte, W. S. Deng, S. Margetis, O. A. Grachov, V. Grigoriev, R. L. Ray, E. Potrebenikova, V. V. Belaga, T. Ljubicic, F. Retiere, N. G. Minaev, H. Caines, V. L. Rykov, Peter Graham Jones, L. Didenko, J. Schambach, E. L. Hjort, J. Balewski, M. C. de la Barca Sánchez, A. Lebedev, M. M. de Moura, Marie Germain, Claude Andre Pruneau, Y. Panebratsev, G. Rai, A. N. Zubarev, R. Zoulkarneev, J. Klay, Jinghui Yang, G. LoCurto, S. R. Klein, O. Barannikova, D. L. Olson, M. DeMello, M. Oldenburg, V. Emelianov, A. A. Derevschikov, D. Keane, Nikolai Smirnov, R. Stock, L. G. Efimov, Yu. Ivanshin, B. E. Bonner, O. D. Tsai, and M. I. Ferguson

Subjects
Physics, Range (particle radiation), Particle physics, Proton, General Physics and Astronomy, Baryon, Nuclear physics, Pair production, Antiproton, High Energy Physics::Experiment, Rapidity, Nuclear Experiment, Nucleon, Energy (signal processing)
Abstract

We report results on the ratio of mid-rapidity anti-proton to proton yields in Au+Au collisions at $\rts = 130$ GeV per nucleon pair as measured by the STAR experiment at RHIC. Within the rapidity and transverse momentum range of $|y

Published
2001
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28. Elliptic Flow inAu+AuCollisions at√sNN=130GeV

Author

N. Stone, Christophe Pierre Suire, A. Lebedev, B. Miller, M. M. de Moura, M. Dialinas, P. Middlekamp, J. Scheblien, V. Ghazikhanian, A. Etkin, A. H. Tang, A. P. Meschanin, R.Kh. Kutuev, J. Berger, J. L. Romero, V. Fine, J. Engelage, T. J. Humanic, Peter J. Lindstrom, D. Zimmerman, I.A. Savin, N. T. Porile, Yu A. Matulenko, M. Horsley, Thomas LeCompte, B. Stringfellow, J. Sedlmeir, L. Smykov, E. Finch, T. S. McShane, J. W. Harris, Joakim Nystrand, V. B. Dunin, J. Grabski, P. Seyboth, D. Dayton, C. J. Liaw, R. Bossingham, J. N. Marx, C. Drancourt, S. Tonse, W. S. Deng, J. G. Cramer, R. A. Scheetz, A. Stolpovsky, H. Hümmler, L. Kotchenda, G. Koehler, E. Gushin, G. J. Kunde, P. Yepes, V. Eckardt, M. Kramer, A. I. Pavlinov, Y. Panebratsev, D. Grosnick, Granville Ott, G. Eppley, A. V. Brandin, V. Trofimov, J. M. Landgraf, M. Strikhanov, K. Krueger, M. B. Tonjes, E. I. Shakaliev, A. Yokosawa, Jinghui Yang, E. Sugarbaker, J. Hunter, H. Z. Huang, V. Morozov, A. Tarchini, S. V. Razin, K. Wilson, G. Rai, Y. Shi, G. Van Buren, J. M. Nelson, P. A. DeYoung, J. Pluta, C. Roy, H. Stroebele, J. Carroll, C. Byrd, N. Xu, G. D. Westfall, D. Padrazo, R. Wells, C. Struck, W. Pinganaud, D. Hardtke, F. Laue, J.F. Amsbaugh, Jay Roberts, N. Adams, David Fritz, J. Sandweiss, G. LoCurto, A. C. Saulys, S. R. Klein, C. E. Allgower, R. D. Majka, J. Zhu, Sergey Voloshin, J. Sowinski, Matthew Nguyen, W. Peryt, J. Takahashi, J. Wolf, C. Feliciano, Y. Fisyak, L. Greiner, K. J. Foley, J. Schambach, E. L. Hjort, S. Pirogov, A. Ogawa, Ian Johnson, Krista M. Marks, S. E. Vigdor, Vladimir Petrov, C. L. Kunz, Z. Li, O. Barannikova, D. L. Olson, F. P. Brady, Gerald W Hoffmann, S. P. Chernenko, D. Seliverstov, A. Schüttauf, Christian Claude Kuhn, W. J. Llope, Q. Li, C. O. Blyth, C. F. Moore, M. Cherney, H. Fessler, W. Christie, Thomas Michael Cormier, D.E. Greiner, T. Krupien, Torre Wenaus, Masashi Kaneta, Ross Schlueter, W. M. Zhang, Andrey Vasiliev, D. Hill, Richard C. Jared, M. Calderón de la Barca Sánchez, R. Weidenbach, T. Nguyen, A. Cardenas, Peter Martin Jacobs, N. Schmitz, S. Chatopadhyay, P. Nevski, M. Lopez-Noriega, A. Klyachko, R. Witt, E. Yamamoto, J. Klay, Thomas A. Trainor, W. R. Edwards, P. Sappenfield, N.D. Gagunashvili, J. Baudot, E. A. Matyushevski, P. Kuczewski, J. C. Dunlop, A. A. Derevschikov, K. Olchanski, V. I. Danilov, C. P. Lansdell, Wilfred J. Braithwaite, E. Mogavero, R.J.M. Snellings, Janet Elizabeth Seger, J. Lin, M. A. C. Lamont, S. B. Nurushev, Z. Milosevich, B. Lasiuk, J. Wisdom, Y. V. Zanevski, F. Retiere, W. Hunt, V. Kormilitsyne, D. Russ, B. E. Bonner, J. T.M. Chrin, G. S. Mutchler, H. Diaz, J. R. Hall, Zubayer Ahammed, G. A. Ososkov, M. J. LeVine, B. Norman, J. Gross, H. Long, K. Bradley, Yu Chen, Wen-Chang Chen, N. G. Minaev, O. D. Tsai, R. P. Scharenberg, Marie Germain, R. Seymour, M. A. Howe, B. Choi, R. Marstaller, W. Betts, Vladimir Tikhomirov, Salahuddin Ahmad, I. Polk, H. S. Matis, G. C. Harper, A. S. Hirsch, P. Kravtsov, A. Maliszewski, Alexander Kovalenko, L. V. Nogach, L. C. Bland, S. Bennett, H. J. Crawford, I. Vakula, C. Adler, F. S. Bieser, L. Wood, A. N. Zubarev, C. A. Ogilvie, G. Brugalette, V. S. Shvetcov, L. S. Schroeder, J. Meier, H. Liu, S. U. Pandey, A. E. Yakutin, I. Flores, Morton Kaplan, V. Perevotchikov, C. A. Whitten, M. Pentia, Marek Gazdzicki, L. Lakehal-Ayat, D. Lopiano, S. Trentalange, A. Ridiger, W. W. Jacobs, M. I. Ferguson, J. Lamas-Valverde, C. Gojak, M. Botlo, Guy Paic, I. Sakrejda, T. Ngo, E. Platner, B. Minor, V. Lindenstruth, V. A. Nikitin, S. Heppelmann, D. Flierl, Ma Bloomer, John Z. H. Zhang, A. Chikanian, S. S. Shimanskii, J. Mitchell, E. G. Judd, L. Martin, Jeffrey G. Reid, B. K. Srivastava, I. M. Vasilevski, K. E. Shestermanov, V. V. Belaga, Lincoln D. Carr, J. Gans, S. Lange, L. Arnold, Boris Hippolyte, G. Skoro, M. Heffner, J. E. Draper, J. Puskar-Pasewicz, R. Morse, V. Grigoriev, J. P. Coffin, O. V. Rogachevski, N. Bouillo, M. DeMello, S. J. Lindenbaum, N. Mikhalin, A. Boucham, H. Ward, M. Oldenburg, Peter Graham Jones, R. L. Ray, V. Emelianov, D. Keane, A. R. Baldwin, A. A. P. Suaide, L. Didenko, Damien Bonnet, Nikolai Smirnov, R. Stock, S. Y. Panitkin, E. Potrebenikova, W. J. Leonhardt, S. Bekele, S. Bouvier, V. P. Kenney, L. G. Efimov, Frank Jm Geurts, Yu. Ivanshin, J. Castillo, S. W. Wissink, R. L. Brown, W. Dominik, P. Jensen, A. Ishihara, T. Ljubicic, Alexander Khodinov, Robert Stone, M. Tokarev, G. Guilloux, Robert R. J. Maier, D. DiMassimo, E. Anderssen, A. M. VanderMolen, H. H. Wieman, H. Caines, S. Jacobson, D. Shuman, R. Willson, D. G. Underwood, J. Wirth, D. Reichhold, T. J. Hallman, T. J. M. Symons, K. Turner, A. Szanto de Toledo, A. M. Poskanzer, J. Tarzian, P. He, K. Solberg, T. Pawlak, A. Vanyashin, Z. Sandler, B. Caylor, R. S. Longacre, V. L. Rykov, J. Porter, G. Igo, J. Seyboth, P. Fachini, D. D. Weerasundara, Mingshui Chen, M. Grau, S. Margetis, O. A. Grachov, M. Schulz, J. R. Lutz, Rainer Arno Ernst Renfordt, J. Balewski, H. G. Ritter, Claude Andre Pruneau, H. Arnesen, R. Zoulkarneev, R. Bellwied, A. S. Konstantinov, K. H. Ackermann, D. M. Moltz, A. A. Kuznetsov, Ivan Kotov, T. Noggle, V. M. Leontiev, Olivier Ravel, J. Whitfield, T. Ullrich, D. Roehrich, B. Erazmus, Z. Z. Xu, D. Cebra, C. Consiglio, M. Beddo, Yu Melnick, P. Leszczynski, J. Bercovitz, T. Herston, J. Riso, Lee Stuart Barnby, V. A. Moiseenko, Marcelo Gameiro Munhoz, D. J. Prindle, E. J. Stephenson, M. A. Lisa, W. A. Love, T. Nussbaum, Daniel Ferenc, Fuqiang Wang, H. Bichsel, G. Odyniec, V. I. Yurevich, E. S. Braithwaite, J. Boehm, T. Eggert, David Lynn, L. Madansky, R. Sanchez, J. Dioguardi, J. H. Thomas, L. Conin, G. Visser, G. S. Averichev, C. P. McParland, H. M. Spinka, J. Rasson, Chinh Vu, and Matthew J. Anderson

Subjects
Physics, Particle physics, Time projection chamber, Hadron, Elliptic flow, General Physics and Astronomy, Observable, Particle accelerator, Charged particle, law.invention, Nuclear physics, law, Pseudorapidity, Nuclear Experiment, Relativistic Heavy Ion Collider
Abstract

Elliptic flow from nuclear collisions is a hadronic observable sensitive to the early stages of system evolution. We report first results on elliptic flow of charged particles at midrapidity in Au+Au collisions at √(sNN) = 130 GeV using the STAR Time Projection Chamber at the Relativistic Heavy Ion Collider. The elliptic flow signal, v₂, averaged over transverse momentum, reaches values of about 6% for relatively peripheral collisions and decreases for the more central collisions. This can be interpreted as the observation of a higher degree of thermalization than at lower collision energies. Pseudorapidity and transverse momentum dependence of elliptic flow are also presented.

Published
2001
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29. Possible observation of the orbital in 96249Cm

Author

John P. Greene, G.P.A. Berg, B. B. Back, W.R. Lozowski, T. Yamanaka, L. R. Morss, C. C. Foster, A. D. Bacher, W. M. Schmitt, E. J. Stephenson, T. Ishii, I. Ahmad, and R. R. Chasman

Subjects
Physics, Momentum, Nuclear and High Energy Physics, Angular momentum, Spectrometer, law, Cyclotron, Alpha particle, Atomic physics, Excitation, Spectral line, Ion, law.invention
Abstract

The position of the K 17 2 shell orbital plays a significant role in determining the shell correction energy and hence the stability of the superheavy elements. A deformed component of this orbital, 1 2 + [880] , comes down in energy with increasing prolate deformation, and is expected to have an excitation energy of less than 2 MeV in nuclei with N = 153. We have performed the reaction 248Cm(4He,3He) using 98.5-MeV alpha particles from the IUCF cyclotron to populate high-l states in 249Cm. this reaction preferentially excites high-l states because of the angular momentum mismatch. The emerging 3He ions were momentum analyzed with the K600 magnetic spectrometer. Spectra were measured at θcm = 4.1°, 6.1°, 10.2°, 12.2°, and 16.2° The spectrometer was calibrated with the 208Pb(4He,3He) and 232Th(4He,3He) reactions at the same incident energy. Three strong peaks were identified in the 248Cm(4He,3He) spectrum and these have been given tentative assignments: 593 keV, 15 2 11 2 − [725] ; 1560 keV and 1898 keV, 17 2 1 2 + [880] , 15 2 13 2 − [716] . Our data do not distinguish between the 17 2 + and 15 2 − assignments.

Published
1999
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30. High-resolution study ofTz=+2→+1Gamow-Teller transitions in the44Ca(3He,t)44Sc reaction

Author

E. Ganioglu, Rhiannon Meharchand, Hooi Jin Ong, Takashi Suzuki, E. J. Stephenson, D. Ishikawa, J. M. Deaven, Katsuya Hirota, C. Scholl, Georgios Perdikakis, Hisanori Fujita, Hiroaki Matsubara, H. Okamura, Yoshitaka Fujita, F. Molina, A. Krasznahorkay, Taka Otsuka, G. Susoy, T. Adachi, R. G. T. Zegers, E. Estevez-Aguado, M. Csatlós, B. Blank, Michio Honma, Juzo Zenihiro, Y. Shimbara, Carol Guess, J. Gulyás, Atsushi Tamii, Kichiji Hatanaka, B. Rubio, A. Algora, and J. H. Thies

Subjects
Physics, Nuclear and High Energy Physics, Spectrometer, 010308 nuclear & particles physics, Scattering, High resolution, 01 natural sciences, Beta decay, Beamline, Double beta decay, 0103 physical sciences, Atomic physics, 010306 general physics, Excitation
Published
2013
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31. Erratum: Synchrotron oscillation effects on an rf-solenoid spin resonance [Phys. Rev. ST Accel. Beams 15, 124202 (2012)]

Author

J. Dietrich, P. Lenisa, A. Polyanskiy, V. Kamerdzhiev, V. Hejny, B. Lorentz, Hans Stockhorst, Yu. Valdau, Frank Rathmann, C. Weidemann, E. J. Stephenson, P. Benati, M. Gaisser, A. Pesce, A.K. Kacharava, P. Kulessa, G. Guidoboni, Ralf Gebel, Yannis K. Semertzidis, D. Prasuhn, D. Chiladze, D. Mchedlishvili, P. Wüstner, William Morse, Andreas Lehrach, D. Öllers, H. Ströher, R. Maier, and Richard Talman

Subjects
Physics, Nuclear and High Energy Physics, Physics and Astronomy (miscellaneous), Condensed matter physics, Oscillation, Resonance, Solenoid, Surfaces and Interfaces, Synchrotron, law.invention, Nuclear physics, law, lcsh:QC770-798, ddc:530, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, Spin (physics)
Published
2013
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32. The 'other' giant dipole resonance: Evidence for the isoscalar giant dipole resonance in 208Pb from inelastic α scattering at 0°

Author

E. J. Stephenson, M. Fujiwara, U. Garg, J Lissanti, D.A. Roberts, W. Reviol, G.P.A. Berg, B.F. Davis, K. Pham, A. D. Bacher, J. W. Jänecke, Yan Alexander Wang, Hidetoshi Akimune, M.N. Harakeh, and C. C. Foster

Subjects
Physics, Nuclear and High Energy Physics, Dipole, Angular distribution, Scattering, Isoscalar, Inelastic scattering, Atomic physics, α particles, Resonance (particle physics), Spectral line
Abstract

The isoscalar giant dipole resonance (ISGDR) in 208 Pb has been investigated using inelastic scattering of 200 MeV α particles at and near 0° where the angular distribution of the ISGDR can be clearly differentiated from other modes. The “difference of spectra” technique was employed to separate the contribution from the high-energy octupole resonance (HEOR). Preliminary angular distribution data provide clear evidence for the ISGDR adjacent to the HEOR.

Published
1996
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33. Synchrotron oscillation effects on an rf-solenoid spin resonance

Author

D. Öllers, D. Chiladze, P. Benati, Frank Rathmann, R. Maier, Yu. Valdau, H. Ströher, A. Polyanskiy, A. Pesce, Andreas Lehrach, P. Wüstner, Ralf Gebel, William Morse, J. Dietrich, V. Hejny, G. Guidoboni, Yannis K. Semertzidis, D. Prasuhn, Hans Stockhorst, A.K. Kacharava, M. Gaisser, C. Weidemann, V. Kamerdzhiev, P. Lenisa, Richard Talman, P. Kulessa, E. J. Stephenson, D. Mchedlishvili, and B. Lorentz

Subjects
solenoid, Nuclear and High Energy Physics, beam dynamics, Physics and Astronomy (miscellaneous), resonance [spin], elastic scattering, Art history, Juelich COSY PS, target [carbon], 01 natural sciences, NO, Nuclear physics, 0103 physical sciences, EDDA, ddc:530, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, 010306 general physics, time dependence [polarization], scintillation counter, Physics, 010308 nuclear & particles physics, measurement methods [electric moment], Beam polarization, Surfaces and Interfaces, sensitivity, effect [synchrotron oscillation], beam [deuteron], elastic scattering, analyzing power, sensitivity, analyzing power, beam profile, Physics::Accelerator Physics, lcsh:QC770-798, National laboratory, polarization [beam]
Abstract

New measurements are reported for the time dependence of the vertical polarization of a 0.97 GeV/c deuteron beam circulating in a storage ring and perturbed by an rf solenoid. The storage ring is the cooler synchrotron (COSY) located at the Forschungszentrum Jülich. The beam polarization was measured continuously using a 1.5 cm thick carbon target located at the edge of the circulating deuteron beam and the scintillators of the EDDA detector. An rf solenoid mounted on the ring was used to generate fields at and near the frequency of the 1-Gγ spin resonance. Measurements were made of the vertical beam polarization as a function of time with the operation of the rf solenoid in either fixed or continuously variable frequency mode. Using rf-solenoid strengths as large as 2.66×10^{-5} revolutions/turn, slow oscillations (∼1 Hz) were observed in the vertical beam polarization. When the circulating beam was continuously electron cooled, these oscillations completely reversed the polarization and showed no sign of diminishing in amplitude. But for the uncooled beam, the oscillation amplitude was damped to nearly zero within a few seconds. A simple spin-tracking model without the details of the COSY ring lattice was successful in reproducing these oscillations and demonstrating the sensitivity of the damping to the magnitude of the synchrotron motion of the beam particles. The model demonstrates that the characteristic features of measurements made in the presence of large synchrotron oscillations are distinct from the features of such measurements when made off resonance. These data were collected in preparation for a study of the spin coherence time, a beam property that needs to become long to enable a search for an electric dipole moment using a storage ring.

Published
2012
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34. High-resolution study of Gamow-Teller transitions via the54Fe(3He,t)54Co reaction

Author

A.D. Bacher, Y. Tameshige, Yuji Shimizu, E. Jacobs, C. C. Foster, J. W. Jänecke, T. Black, K. Katori, Katsumasa Fujita, E. J. Stephenson, L. Popescu, A. Negret, K. Nakanishi, K. Kanzaki, T. Adachi, Atsushi Tamii, D. De Frenne, M. Yosoi, Hideki Ueno, D. A. Roberts, G. P. A. Berg, T. Yamanaka, Takaharu Otsuka, Yasuhiro Sakemi, Michio Honma, K. O. Zell, Kichiji Hatanaka, Yoshitaka Fujita, Y. Shimbara, Masaki Uchida, and Hisanori Fujita

Subjects
Physics, Nuclear and High Energy Physics, Isovector, Isoscalar, Isospin, Type (model theory), Atomic physics, Nucleon, Resonance (particle physics), Energy (signal processing), Spin-½
Abstract

The Gamow-Teller transition strengths, $B$(GT), in $pf$-shell nuclei are of interest in nuclear physics as well as in nuclear astrophysics. A high-resolution (${}^{3}\mathrm{He},t$) charge-exchange (CE) reaction was performed on the ${T}_{z}=+1$ nucleus ${}^{54}$Fe at 0${}^{\ensuremath{\circ}}$ and at an intermediate incident energy of 140 MeV/nucleon for the study of precise GT transition strengths to the final ${T}_{z}=0$ nucleus ${}^{54}$Co. By applying dispersion matching techniques for a high-quality ${}^{3}$He beam at RCNP, an energy resolution of 21 keV and an angular resolution of 5 mr were realized. The bumplike structure of the GT resonance observed in low-resolution CE reactions at around the excitation energy (${E}_{x}$) of 10 MeV was resolved in individual $L$ $=$ 0, GT states. Excitation strengths were obtained for these GT states. If the ${R}^{2}$ value that is defined by the ratio between GT and Fermi unit cross sections is known, the $B$(GT) values can be determined from the excitation strengths. For the derivation of the ${R}^{2}$ value, the ``merged analysis'' combining the GT strength distribution from the ${}^{54}$Fe(${}^{3}\mathrm{He},t$)${}^{54}$Co study and the half-life from a ${}^{54}$Ni $\ensuremath{\beta}$ decay was used, where $T=1$ isospin symmetry for $A=54$ isobars was assumed. The GT strengths were compared with a shell-model calculation using the GXPF1 interaction. The final GT states can have the isospin values $T$ $=$ 0, 1, and 2. The isospin $T$ of each GT state observed in the $8.3\ensuremath{\le}{E}_{x}\ensuremath{\le}12.0$ MeV region of the ${}^{54}$Fe(${}^{3}\mathrm{He},t$)${}^{54}$Co spectrum was identified by comparing the excitation strength with that of corresponding $M1$ state observed in a ${}^{54}$Fe($p,{p}^{\ensuremath{'}}$)${}^{54}$Fe experiment. The $B$(GT) values of the states identified to have $T=2$, in particular, are of importance for the calculation of the electron capture rates at the core-collapse stage of presupernovae. The $B$(GT) strengths were further compared with $B(M1)$ strengths measured in the ${}^{54}$Fe($e,{e}^{\ensuremath{'}}$)${}^{54}$Fe reaction. In the $M1$ excitation using an electromagnetic probe, isoscalar (IS) and isovector (IV) orbital type operators are active in addition to the IV spin type operator that mediates the GT transitions. The contributions of the IS and IV orbital terms were studied by calculating the ratio of the strengths of analogous $M1$ and GT transitions.

Published
2012
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35. Looking for the isoscalar giant dipole resonance in 208Pd using inelastic a scattering at and near O°

Author

Muhsin N. Harakeh, E. J. Stephenson, M. Fujiwara, J. Ussanti, Hidetoshi Akimune, G.P.A. Berg, K. Pham, A. D. Bacher, U. Garg, Yan Alexander Wang, W. Reviol, B.F. Davis, J. W. Jänecke, and D.A. Roberts

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Dipole, Angular distribution, Scattering, Isoscalar, Inelastic scattering, Atomic physics, Resonance (particle physics), α particles, Spectral line
Abstract

The isoscalar giant dipole resonance (ISGDR) in 208Pb has been investigated using inelastic scattering of 200 MeV α particles at and near 0° where the angular distribution of the ISGDR can be clearly differentiated from other modes. The “difference of spectra” technique was employed to separate the contribution from the high-energy octupole resonance (HEOR). Results from a preliminary analysis of the data are consistent with the expected positions of the ISGOR and HEOR, as well as their expected angular distributions near 0°.

Published
1994
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36. Performance of a neutron polarimeter to measure the electric form factor of the neutron

Author

S. Kowalski, E. J. Stephenson, B. Ni, E. Steinfelds, B. D. Anderson, P. Markowitz, J. W. Watson, J.M. Cameron, R. Lourie, C.C. Foster, M. Spraker, P.J. Pella, A. R. Baldwin, J. M. Finn, James J. Kelly, R. Madey, T. Eden, J. Schambach, and W. M. Zhang

Subjects
Physics, Nuclear and High Energy Physics, Proton, Detector, Cyclotron, Electric form factor, Polarimeter, Polarization (waves), Neutron temperature, law.invention, Nuclear physics, law, Neutron, Instrumentation
Abstract

We measured the analyzing power and the efficiency of a neutron polarimeter that was designed and constructed to measure the neutron electric form factorGEn. The measurement was carried out at the Indiana University Cyclotron Facility (IUCF) with the 14 C ( p , n ) 14 N reaction at a proton beamenergy of 138.4 MeV. The analyzing power, 〈Ay〉, averaged over the acceptance of the polarimeter is typically 0.44±0.02−0.03+0.04 at a neutron energy of 135 MeV. With a lead-steel wall, consisting of 4 in. of lead sandwiched between two 1 3 8 -in. steel plates, ahead of the polarimeter, the average analyzing power is the same within statistics, namely, 〈Ay〉 = 0.43 ± 0.02−0.03+0.04. The large systematic uncertainty quoted here is dominated by an uncertainty from the inability at the time of the experiment of measuring the longitudinal polarization component of the sideways polarized protons; this systematic uncertainty can be reduced significantly to 0.02 in any future calibration at the IUCF. In each case, the efficiency of the polarimeter is about 0.26% for 135 MeV neutrons at a pulse-height threshold of 4 MeV equivalent electron energy (MeVee) on the front detectors and 10 MeVee on the rear detectors. This analysis reveals a small analyzing power from the carbon in the front-analyzer detectors.

Published
1994
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38. Search for 3s1/2hole-strength fragments via the208Pb(d,3He)207Tl reaction

Author

H. Nann, G J Wagner, A. Mondry, P.P. Singh, D.W. Miller, G. P. A. Berg, P. Woldt, E. J. Stephenson, J. Lisantti, and P. Grabmayr

Subjects
Physics, Nuclear and High Energy Physics, Proton, Excited state, Atomic physics, Nuclear Experiment, Excitation
Abstract

In an attempt to locate weak fragments of the 3s proton hole strength in 207Tl the 208Pb(d, 3He)207Tl reaction was studied at Ed=80 MeV. The spectrum is dominated by five single-hole states. A careful analysis of the remaining, weakly excited states below 5 Mev of excitation energy reveals no additional 3s strength. For the total excited 3s strength an upper limit of 5% of the ground-state strength is obtained.

Published
1992
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39. Non-spin-flip (3He, t) charge-exchange and isobaric analog states of actinide nuclei studied at and 200 MeV

Author

G. Brouwer, R. Sawafta, E. J. Stephenson, S.Y. van der Werf, M.B. Greenfield, J.M. Schippers, A.M. van den Berg, D. Stewart, Fredrick D. Becchetti, A. Nadasen, J. W. Jänecke, G.P.A. Berg, D.A. Roberts, M.A. Hofstee, and Muhsin N. Harakeh

Subjects
Physics, Nuclear reaction, Nuclear and High Energy Physics, Isovector, Isospin, Nuclear Theory, Coulomb, Isobaric process, Resonance, Spin-flip, Atomic physics, Nuclear Experiment, Spectral line
Abstract

The (He-3, t) charge-exchange reaction has been studied at theta = 0-degree-C and bombarding energies of E(He-3) = 76.5 MeV and 200 MeV. Spectra were measured using magnetic analysis for target nuclei of C-12, C-13, O-16, F-19, Si-28, Si-29, Si-30, Zr-90, Sn-117, Sn-120, (nat)Ta, (nat)W, Au-197, Pb-208, Th-230, Th-232, U-234, U-236, U-238 and Pu-244. The measurements at 76.5 MeV concentrated on the isobaric analog states of several actinide nuclei, particularly on their widths and the branching ratios for proton decay. Cross sections, Q-values and total widths were determined for the transitions to the isobaric analog states. Coulomb displacement energies derived from the measured Q-values display the influence of deformed nuclear shapes. Escape widths GAMMA-up and spreding widths GAMMA-down of the isobaric analog states in five actinide nuclei were deduced from the measured proton-decay branching ratios. They were found to be in agreement with predictions which postulate isospin mixing via the Coulomb force with the (T0-1)-component of the isovector giant monopole resonance. The measurements at 200 MeV were concerned with transitions to isobaric analog states in both light and heavy nuclei, including several actinide nuclei, but Gamow-Teller resonances and transitions to numerous other states were also observed. The measured cross sections for several transitions to isobaric analog states from Si-30 to Pb-208 were used to extract the effective interaction V(tau) for non-spin-flip (He-3, t) charge exchange at E(He-3) almost-equal-to 200 MeV. The interaction strength V(tau) decreases by a factor 0.6 when compared to previously measured values for the energy range E(He-3) = 65 to 90 MeV. An angular distribution from theta(t) = 0-degree to 16-degrees for the transition to the isobaric analog state in Sb-120 measured at E(He-3) = 200 MeV was found to be in very good agreement with microscopic calculations.

Published
1991
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40. Run05 Proton Beam Polarization Measurements by pC-Polarimeter (ver. 1.1)

Author

D. Svirida, T. Wise, A. Nass, G. Bunce, A. Bravar, W. Haeberli, S. Dhawan, A. Zelenski, Hiroyuki Okada, I. Nakagawa, K. O. Eyser, J. Wood, A. Bazilevsky, I. Alekseev, E. J. Stephenson, Y. Makdisi, H. Huang, R. L. Gill, and K. Yip

Subjects
Physics, Hydrogen, chemistry, Ribbon, chemistry.chemical_element, Beam polarization, Polarimeter, Atomic physics, Approx, Nuclear Experiment, Relativistic Heavy Ion Collider, Polarization (waves), Beam (structure)
Abstract

The polarization of the proton beams [1, 2] at the Relativistic Heavy Ion Collider (RHIC)[3] RHIC ring. The H-Jet polarimeter is located at the collision point allowing measurements of absolute normalization is provided by the hydrogen polarimeter, which measures over 1 {approx} 2 another measurement rather than measuring the absolute polarization. both beams. Two identical pC-polarimeters are equipped in the yellow and blue rings, where carbon ribbon target, providing fast feedback to beam operations and experiments. The days to obtain {approx} 5% statistical uncertainty (in Run05). Thus, the operation of the carbon is measured using both an atomic beam source hydrogen gas jet (H-Jet)[4, 5] and proton-carbon polarimeters was focused on better control of relative stability between one measurement to statistical accuracy within 20 to 30 seconds using an ultra-thin (typically 6 {approx} 8 {micro}g/cm{sup 2}) the rings are separated. The pC-polarimeter measures relative polarization to a few percent.

Published
2008
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41. Experimental Verification of Predicted Beam-Polarization Oscillations near a Spin Resonance

Author

D. W. Sivers, E. J. Stephenson, M. F. da Silva, A. Schnase, A. D. Krisch, Alex Chao, K. Ulbrich, Vasiliy Morozov, Bernd Lorentz, M. A. Leonova, Victor K. Wong, D. Welsch, C. J. G. Onderwater, R. Maier, Hans Stockhorst, Ralf Gebel, R. S. Raymond, Andreas Lehrach, D. Prasuhn, A. Garishvili, F. Hinterberger, N. P. M. Brantjes, and Research unit Nuclear & Hadron Physics

Subjects
Physics, Spin polarization, Scattering, SYNCHROTRON, General Physics and Astronomy, Solenoid, COSY, Polarization (waves), Charged particle, Synchrotron, law.invention, DEUTERONS, law, PROTONS, ddc:550, Physics::Accelerator Physics, SCATTERING, Atomic physics, Center frequency, Beam (structure)
Abstract

The Chao matrix formalism allows analytic calculations of a beam's polarization behavior inside a spin resonance. We recently tested its prediction of polarization oscillations occurring in a stored beam of polarized particles near a spin resonance. Using a 1.85 GeV/c polarized deuteron beam stored in the COoler SYnchrotron, we swept a new rf solenoid's frequency rather rapidly through 400 Hz during 100 ms, while varying the distance between the sweep's end frequency and the central frequency of an rf-induced spin resonance. Our measurements of the deuteron's polarization near and inside the resonance agree with the Chao formalism's predicted oscillations.

Published
2008
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42. (DRAFT) ANALYSIS NOTE, Absolute Polarization Determination at RHIC in 2005

Author

A. Zelenski, G. Bunce, T. Wise, Hiroyuki Okada, W. Haeberli, I. Nakagawa, J. Wood, K. O. Eyser, A. Bazilevsky, H. Huang, S. Dhawan, E. J. Stephenson, R. L. Gill, Y. Makdisi, A. Nass, D. Svirida, I. Alekseev, and A. Bravar

Subjects
Physics, Nuclear physics, Particle physics, Quark–gluon plasma, Relativistic Heavy Ion Collider
Published
2007
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43. Absolute measurement of the polarization of high energy proton beams at RHIC

Author

H. Huang, Norio Saito, D. Svirida, A. Khodinov, E. J. Stephenson, Ahovi Kponou, I. G. Alekseev, A. Nass, Y. I. Makdisi, T. Wise, Wuzheng Meng, Hiroyuki Okada, K. O. Eyser, Zheng Li, A. N. Zelenski, V. Zubets, S. Rescia, G. Bunce, M. A. Chapman, Satish Dhawan, O. Jinnouchi, A. Bravar, W. Haeberli, I. Nakagawa, and R. L. Gill

Subjects
Elastic scattering, Physics, Detector, Particle accelerator, Polarization (waves), law.invention, Nuclear physics, High energy nuclear physics, law, Coulomb, Physics::Accelerator Physics, Nuclear Experiment, Relativistic Heavy Ion Collider, Spin (physics)
Abstract

The spin physics program at the relativistic heavy ion collider (RHIC) requires knowledge of the beam polarization to better than 5%. Such a goal is made the more difficult by the lack of knowledge of the analyzing power of high energy nuclear physics processes. To overcome this, a polarized hydrogen jet target was constructed and installed at one intersection region in RHIC where it intersects both beams and utilizes the precise knowledge of the jet atomic hydrogen beam polarization to measure the analyzing power in proton- proton elastic scattering in the nuclear Coulomb interference (CNI) region at the prescribed RHIC proton beam energy. The reverse reaction is used to assess the absolute beam polarization. Simultaneous measurements taken with fast high statistics polarimeters that measure the p-carbon elastic scattering process also in the CNI region use the jet results to calibrate the latter. In this presentation, the status of the polarized jet target mechanics, operation, detector systems, and data analysis results are described. The statistical accuracies as well as the systematic uncertainties will be discussed.

Published
2007
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44. Measurement of the Absolute Differential Cross Section for np Elastic Scattering at 194 MeV

Author

W. W. Jacobs, S. E. Vigdor, S. W. Wissink, Cecilia Johansson, J. Rapaport, B. Bergenwall, A. Klyachko, Joakim Klug, Nils Olsson, Leif Nilsson, Todd W. Hossbach, T. Rinckel, Yaoqi Zhou, P. Nadel-Turonski, M. Planinic, M. Sarsour, Todd E. Peterson, Stephan Pomp, Jan Blomgren, Udomrat Tippawan, C. E. Allgower, and E. J. Stephenson

Subjects
Physics, Scattering cross-section, Nuclear reaction, Elastic scattering, Normalization (statistics), Nuclear and High Energy Physics, Particle physics, 010308 nuclear & particles physics, Scattering, Partial wave analysis, FOS: Physical sciences, Neutron radiation, 01 natural sciences, 0103 physical sciences, Nuclear force, Nuclear Experiment (nucl-ex), 010306 general physics, Nuclear Experiment
Abstract

A tagged medium-energy neutron beam has been used in a precise measurement of the absolute differential cross section for np back-scattering. The results resolve significant discrepancies within the np database concerning the angular dependence in this regime. The experiment has determined the absolute normalization with 1.5% uncertainty, suitable to verify constraints of supposedly comparable precision that arise from the rest of the database in partial wave analyses. The analysis procedures, especially those associated with evaluation of systematic errors in the experiment, are described in detail so that systematic uncertainties may be included in a reasonable way in subsequent partial wave analysis fits incorporating the present results., Comment: 22 pages, 21 figures, submitted for publication in Physical Review C

Published
2006
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45. Charge Symmetry Breaking and QCD

Author

E. J. Stephenson, Allena K. Opper, and Gerald A. Miller

Subjects
Quark, Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Field (physics), Nuclear Theory, Hadron, Strong interaction, FOS: Physical sciences, Charge (physics), Nuclear Theory (nucl-th), High Energy Physics - Phenomenology, Pion, High Energy Physics - Phenomenology (hep-ph), High Energy Physics::Experiment, Symmetry breaking, Nuclear Experiment (nucl-ex), Nuclear Experiment
Abstract

Charge symmetry breaking (CSB) in the strong interaction occurs because of the difference between the masses of the up and down quarks. The use of effective field theories allows us to follow this influence of confined quarks in hadronic and nuclear systems. The progress in observing and understanding CSB is reviewed with particular attention to the recent successful observations of CSB in measurements involving the production of a single neutral pion and to the related theoretical progress., Comment: 41 pages, 10 figures, for Nov. 2006 edition Annual Review of Nuclear and Particle Physics

Published
2006
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46. MEASUREMENT OF THE ANALYZING POWER IN PP ELASTIC SCATTERING IN THE PEAK CNI REGION AT RHIC

Author

A. Zelenski, A. Nass, D. Svirida, I. Alekseev, T. Wise, Satish Dhawan, Y. Makdisi, O. Jinnouchi, E. J. Stephenson, Ahovi Kponou, Alexander Khodinov, G. Bunce, Hiroyuki Okada, H. M. Spinka, Norio Saito, Wuzheng Meng, R. L. Gill, A. Bravar, and W. Haeberli

Subjects
010302 applied physics, Physics, Elastic scattering, Proton, Scattering, Momentum transfer, FOS: Physical sciences, Absolute value, Polarization (waves), 01 natural sciences, 7. Clean energy, Nuclear physics, Recoil, 0103 physical sciences, High Energy Physics::Experiment, Nuclear Experiment (nucl-ex), Nuclear Experiment, 010306 general physics, Spin-½
Abstract

We report the first measurements of the A_N absolute value and shape in the -t range from 0.0015 to 0.010GeV/c^2 with a precision better than 0.005 for each A_N data point using a polarized atomic hydrogen gas jet target and the 100 GeV RHIC proton beam., Comment: 4 pages, 5 figures

Published
2005
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47. Measurement of the AbsolutenpScattering Differential Cross Section at 194 MeV

Author

E. J. Stephenson, S. E. Vigdor, C. E. Allgower, A. Klyachko, Todd E. Peterson, Cecilia Johansson, S. W. Wissink, T. Rinckel, M. Sarsour, B. Bergenwall, Jan Blomgren, Yaoqi Zhou, M. Planinic, Udomrat Tippawan, Joakim Klug, Leif Nilsson, J. Rapaport, Nils Olsson, Stephan Pomp, Todd W. Hossbach, W. W. Jacobs, and P. Nadel-Turonski

Subjects
Elastic scattering, Coupling constant, Physics, 010308 nuclear & particles physics, Scattering, FOS: Physical sciences, General Physics and Astronomy, Magnitude (mathematics), Neutron scattering, Neutron radiation, 01 natural sciences, Measure (mathematics), Nuclear physics, Cross section (physics), 0103 physical sciences, Nuclear Experiment (nucl-ex), Nuclear Experiment, 010306 general physics
Abstract

We describe a double-scattering experiment with a novel tagged neutron beam to measure differential cross sections for np back-scattering to better than 2% absolute precision. The measurement focuses on angles and energies where the cross section magnitude and angle-dependence constrain the charged pion-nucleon coupling constant, but existing data show serious discrepancies among themselves and with energy-dependent partial wave analyses (PWA). The present results are in good accord with the PWA, but deviate systematically from other recent measurements., 4 pages, 4 figures

Published
2005
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48. Inclusion of nonspherical components of the Pauli blocking operator in (p,p') reactions

Author

R. C. Johnson, Francesca Sammarruca, and E. J. Stephenson

Subjects
Physics, Nuclear and High Energy Physics, Angular momentum, Proton, 010308 nuclear & particles physics, Nuclear Theory, Observable, Parity (physics), Inelastic scattering, Spin structure, Nuclear matter, 01 natural sciences, 7. Clean energy, symbols.namesake, Pauli exclusion principle, Quantum electrodynamics, 0103 physical sciences, symbols, Nuclear Experiment, 010306 general physics
Abstract

We present the first calculations of proton elastic and inelastic scattering in which the Pauli blocking operator contains the leading nonspherical components as well as the usual spherical (angle-averaged) part. We develop a formalism for including the contributions to the effective nucleon-nucleon interaction from the resulting new $G$-matrix elements that extend the usual two-nucleon spin structure and may not conserve angular momentum. We explore the consequences of parity conservation, time-reversal invariance, and nucleon-nucleon antisymmetrization for the new effective interaction. Changes to the calculated cross section and spin observables are small in the energy range from 100 to 200 MeV.

Published
2005
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49. Rapidity and centrality dependence of proton and antiproton production fromAu197+Au197collisions atSNN=130GeV

Author

J. Adams, C. Adler, M. M. Aggarwal, Z. Ahammed, J. Amonett, B. D. Anderson, M. 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, P. Bhaskar, A. K. Bhati, H. Bichsel, A. Billmeier, L. C. Bland, C. O. Blyth, B. E. Bonner, M. Botje, A. Boucham, A. Brandin, A. Bravar, R. V. Cadman, X. Z. Cai, H. Caines, M. Calderón de la Barca Sánchez, A. Cardenas, J. Carroll, J. Castillo, M. Castro, D. Cebra, P. Chaloupka, S. Chattopadhyay, H. F. Chen, Y. Chen, S. P. Chernenko, M. Cherney, A. Chikanian, B. Choi, 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, X. Dong, J. E. Draper, F. Du, A. K. Dubey, V. B. Dunin, J. C. Dunlop, M. R. Dutta Mazumdar, V. Eckardt, L. G. Efimov, V. Emelianov, J. Engelage, G. Eppley, B. Erazmus, P. Fachini, V. Faine, J. Faivre, R. Fatemi, K. Filimonov, P. Filip, E. Finch, Y. Fisyak, D. Flierl, K. J. Foley, J. Fu, C. A. Gagliardi, M. S. Ganti, T. D. Gutierrez, N. Gagunashvili, J. Gans, L. Gaudichet, M. Germain, F. Geurts, V. Ghazikhanian, P. Ghosh, J. E. Gonzalez, O. Grachov, V. Grigoriev, D. Grosnick, M. Guedon, S. M. Guertin, A. Gupta, E. Gushin, T. J. Hallman, D. Hardtke, J. W. Harris, M. Heinz, T. W. Henry, S. Heppelmann, T. Herston, B. Hippolyte, A. Hirsch, E. Hjort, G. W. Hoffmann, M. Horsley, H. Z. Huang, S. L. Huang, T. J. Humanic, G. Igo, A. Ishihara, P. Jacobs, W. W. Jacobs, M. Janik, I. Johnson, P. G. Jones, E. G. Judd, S. Kabana, M. Kaneta, M. Kaplan, D. Keane, J. Kiryluk, A. Kisiel, J. Klay, S. R. Klein, A. Klyachko, D. D. Koetke, T. Kollegger, A. S. Konstantinov, M. Kopytine, L. Kotchenda, A. D. Kovalenko, M. Kramer, P. 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, C. P. Lansdell, B. Lasiuk, F. Laue, J. Lauret, A. Lebedev, R. Lednický, V. M. Leontiev, 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, A. P. Mahapatra, R. Majka, R. Manweiler, S. Margetis, C. Markert, L. Martin, J. Marx, H. S. Matis, Yu. A. Matulenko, T. S. McShane, F. Meissner, Yu. Melnick, A. Meschanin, M. Messer, M. L. Miller, Z. Milosevich, N. G. Minaev, C. Mironov, D. Mishra, J. Mitchell, B. Mohanty, L. Molnar, C. F. Moore, M. J. Mora-Corral, V. Morozov, M. M. de Moura, M. G. Munhoz, B. K. Nandi, S. K. Nayak, T. K. Nayak, J. M. Nelson, P. Nevski, V. A. Nikitin, L. V. Nogach, B. Norman, S. B. Nurushev, G. Odyniec, A. Ogawa, V. Okorokov, M. Oldenburg, D. Olson, G. Paic, S. U. Pandey, S. Pal, Y. Panebratsev, S. Y. Panitkin, A. I. Pavlinov, T. Pawlak, V. Perevoztchikov, W. Peryt, V. A. Petrov, S. C. Phatak, R. Picha, 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. Rogachevski, J. L. Romero, A. Rose, C. Roy, L. J. Ruan, V. Rykov, R. Sahoo, I. Sakrejda, S. Salur, J. Sandweiss, I. Savin, J. Schambach, R. P. Scharenberg, N. Schmitz, L. S. Schroeder, K. Schweda, J. Seger, D. Seliverstov, P. Seyboth, E. Shahaliev, M. Shao, M. Sharma, K. E. Shestermanov, S. S. Shimanskii, R. N. Singaraju, F. Simon, G. Skoro, N. Smirnov, R. Snellings, G. Sood, P. Sorensen, J. Sowinski, H. M. Spinka, B. Srivastava, S. Stanislaus, E. J. Stephenson, 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, V. Tikhomirov, M. Tokarev, M. B. Tonjes, T. A. Trainor, S. Trentalange, R. E. Tribble, M. D. Trivedi, V. Trofimov, O. Tsai, T. Ullrich, D. G. Underwood, G. Van Buren, A. M. Vander Molen, A. N. Vasiliev, M. Vasiliev, S. E. Vigdor, Y. P. Viyogi, S. A. Voloshin, F. Wang, G. Wang, X. L. Wang, Z. M. Wang, H. Ward, J. W. Watson, R. Wells, G. D. Westfall, C. Whitten, H. Wieman, R. Willson, S. W. Wissink, R. Witt, J. Wood, J. Wu, N. Xu, Z. Xu, Z. Z. Xu, A. E. Yakutin, E. Yamamoto, J. Yang, P. Yepes, V. I. Yurevich, Y. V. Zanevski, I. Zborovský, H. Zhang, H. Y. Zhang, W. M. Zhang, Z. P. Zhang, P. A. Żołnierczuk, R. Zoulkarneev, J. Zoulkarneeva, and A. N. Zubarev

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Proton, Mass distribution, 010308 nuclear & particles physics, Elliptic flow, Order (ring theory), 01 natural sciences, Nuclear physics, Transverse plane, Antiproton, 0103 physical sciences, Transverse mass, Rapidity, Nuclear Experiment, 010306 general physics
Abstract

We report on the rapidity and centrality dependence of proton and anti-proton transverse mass distributions from {sup 197}Au + {sup 197}Au collisions at {radical}s{sub NN} = 130 GeV as measured by the STAR experiment at RHIC. Our results are from the rapidity and transverse momentum range of |y| < 0.5 and 0.35 < p{sub t} < 1.00 GeV/c. For both protons and anti-protons, 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(anti-proton) yields and transverse mass distributions the possibility of pre-hadronic collective expansion may have to be taken into account.

Published
2004
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50. New Method of Measuring Electric Dipole Moments in Storage Rings

Author

Yannis K. Semertzidis, F. J. M. Farley, E. J. Stephenson, B. L. Roberts, J. P. Miller, Yuri F. Orlov, Alexander J. Silenko, William Morse, Klaus-Peter Jungmann, and KVI - Center for Advanced Radiation Technology

Subjects
Systematic error, Physics, Muon, Physics beyond the Standard Model, MUON, FOS: Physical sciences, General Physics and Astronomy, Computer Science::Digital Libraries, Measure (mathematics), Charged particle, High Energy Physics - Experiment, Highly sensitive, High Energy Physics - Experiment (hep-ex), Dipole, SEARCH, Quantum electrodynamics, ЕСТЕСТВЕННЫЕ И ТОЧНЫЕ НАУКИ::Физика [ЭБ БГУ], PARTICLES
Abstract

A new highly sensitive method of looking for electric dipole moments of charged particles in storage rings is described. The major systematic errors inherent in the method are addressed and ways to minimize them are suggested. It seems possible to measure the muon EDM to levels that test speculative theories beyond the standard model., 4 pages, Phys. Rev. Lett. 93, 052001, 2004

Published
2004
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