Powered by Deep Web Technologies
Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Hyperon Production with CLAS and CLAS12  

SciTech Connect (OSTI)

Hadron spectroscopy and baryon spectroscopy in particular represents a large part of the experimental program with CLAS at Jefferson Lab. Within this program a substantial amount of data on hyperon production and properties has been accumulated. This includes photo- and electro-production of {Lambda} and {Sigma} hyperons and their excited states and also {Xi} hyperons. Some of the highlights of this program will be presented together with plans to extend this program with CLAS12 after CEBAF upgrade to 12 GeV.

Eugene Pasyuk

2012-12-01T23:59:59.000Z

2

Spin physics with CLAS and CLAS12  

SciTech Connect (OSTI)

An extensive experimental program to measure the spin structure of the nucleon has been conducted in Hall B at Jefferson Lab with the CEBAF Large Acceptance Spectrometer (CLAS) in the last decade. Using a longitudinally polarized beam scattering off longitudinally polarized NH3 and ND3 targets, inclusive Deep Inelastic Scattering (DIS), Semi-Inclusive DIS (SIDIS) and DVCS experiments were carried out that make a significant contributions to the existing data. The inclusive double spin asymmetry A|| was measured over a large range in Q2 and W, providing data of impressively high precision that give a better understanding of the structure of the nucleon in the DIS and the valence quarks regions. Using parameterizations A2 and F1 from world data, the virtual photon asymmetry A1 and the structure function g1 were extracted in a Q2 range from 0.05 to 5 GeV2 and a W range from 1.08 to 3.0 GeV. As a result of the extended kinematical range, first moments of structure functions were measured over a large range in Q2 and duality was tested. Furthermore, newly proposed experiments, using an upgraded accelerator at Jefferson Laboratory and an improved CLAS detector (CLAS12), are expected to increase the statistical precision of the current measurements and extend them to kinematic regions presently not accessible, such as high x. This will improve significantly our knowledge of the structure of the nucleon, including parton distribution functions, duality and higher twists contributions.

Angela Biselli

2011-10-01T23:59:59.000Z

3

phi Photoproduction at CLAS  

SciTech Connect (OSTI)

The cross-section for phi meson photoproduction on the proton has been measured at a photon energy E_gamma = 3.6 GeV up to a four-momentum transfer -t = 4 GeV^2. A measurement of the differential cross-section at such high transfers, down to 100 pb/GeV^2, was only made possible thanks to the combination of the 100% duty cycle of CEBAF and the use of the large acceptance detector CLAS. At low four-momentum transfer, the differential cross-section is in agreement with previous measurements and is well accounted for by the exchange of the Pomeron. At large four-momentum transfer, above -t = 1 GeV^2, no previous data exist, and our results support a model where the Pomeron is resolved into its simplest component, two gluons. Taking into account the coupling of these gluons to any quark in the proton and the phi reproduces quite well the dependence in t of our cross-sections.

E. Anciant; G. Audit; T. Auger; M. Battaglieri; J.M. Laget; C. Marchand; K. McCormick; CLAS Collaboration

2000-05-12T23:59:59.000Z

4

Studies of TMDs with CLAS  

SciTech Connect (OSTI)

Studies of single and double-spin asymmetries in pion electro-production in semi-inclusive deep-inelastic scattering of 5.8 GeV polarized electrons from unpolarized and longitudinally polarized targets at the Thomas Jefferson National Accelerator Facility using CLAS discussed. We present a Bessel-weighting strategy to extract transverse-momentum-dependent parton distribution functions.

Aghasyan, Mher M. [Lab. Naz. Frascati, Frascati, Italy; Avakian, Harut A. [JLAB

2013-07-01T23:59:59.000Z

5

The CLAS Forward Electromagnetic Calorimeter  

SciTech Connect (OSTI)

The CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab utilizes six iron-free superconducting coils to provide an approximately toroidal magnetic field. The six sectors are instrumented individually to form six independent spectrometers. The forward region (8deg < (theta) < 45deg) of each sector is equipped with a lead-scintillator electromagnetic sampling calorimeter (EC), 16 radiation lengths thick, using a novel triangular geometry with stereo readout. With its good energy and position resolution, the EC is used to provide the primary electron trigger for CLAS. It is also used to reject pions, reconstruct pi-0 and eta decays and detect neutrons, This paper treats the design, construction and performance of the calorimeter.

M. Amarian; Geram Asryan; Kevin Beard; Will Brooks; Volker Burkert; Tom Carstens; Alan Coleman; Raphael Demirchyan; Yuri Efremenko; Hovanes Egiyan; Kim Egiyan; Herb Funsten; Vladimir Gavrilov; Kevin L. Giovanetti; R.M. Marshall; Berhard Mecking; R.C. Minehart; H. Mkrtchan; Mavrik Ohandjanyan; Youri Sharabian; L.C. Smith; Stepan Stepanyan; W.A. Stephens; T.Y. Tung; Carl Zorn

2001-05-01T23:59:59.000Z

6

Meson Photoproduction Experiments with CLAS  

SciTech Connect (OSTI)

A large part of the experimental program in Hall B of the Jefferson Lab is dedicated to light baryon spectroscopy. Meson photoprodcution experiments are essential part of this program. CEBAF Large Acceptance Spectrometer (CLAS) and availability of circularly and linearly polarized tagged photon beams and frozen spin polarized targets provide unique conditions for this type of experiments. This combination of experimental tools gives a remarkable opportunity to measure double polarization observables for different pseudo-scalar meson photoproduction processes. For the first time, a complete or nearly complete measurement became possible and will facilitate model independent extraction of the reaction amplitude. An overview of the experimental program and its current status together with recent results on double polarization measurements in ?{sup +} photoproduction are presented.

Eugene Pasyuk

2012-12-01T23:59:59.000Z

7

CLAS-NOTE 2011-006 The CLAS Shifts Schedule and Productivity Management Tools  

E-Print Network [OSTI]

School of Physics and Astronomy, University of Glasgow, Glasgow G12 8QQ, United Kingdom (Dated: April 24. Experimental Program 6 IV. Service Work 6 A. Submission 6 B. Reviews (Audits) 7 C. Summary Tables 8 D. CLAS12-of-its-kind among nuclear and high-energy physics collaborations and was created specifically for the CLAS

Glasgow, University of

8

Simulation Results for CLAS12 From gemc G.P.Gilfoyle, M.Ungaro et al.  

E-Print Network [OSTI]

Simulation Results for CLAS12 From gemc G.P.Gilfoyle, M.Ungaro et al. CLAS12 Software Group Outline Software Workshop - May 25, 2010 ­ p. 7/2 #12;Comparison with CLAS6 - Resolution 1. CLAS6 results from EC used in CLAS6 simulation while Monte Carlo information used for CLAS12, (4) energy loss out the back

Gilfoyle, Jerry

9

Biological Sciences http://www.clas.wayne.edu/biology/  

E-Print Network [OSTI]

Biological Sciences http://www.clas.wayne.edu/biology/ Divisions: Evolutionary and Organismal Biology Molecular Biology and Biotechnology Cellular, Developmental, and Neurobiology #12;Biological Sciences http://www.clas.wayne.edu/biology/ · Cell Biology and Cytogenetics (Beningo, Tucker, Greenberg

Berdichevsky, Victor

10

Magnetic System for the CLAS12 Proposal  

SciTech Connect (OSTI)

The conceptual design of a magnetic system for an experiment to measure the transverse spin effects in semi-inclusive Deep Inelastic Scattering (SIDIS) at 11 GeV with a transversely polarized target using the CLAS12 detector at Jefferson Lab is presented. A proposal has been submitted to study spin azimuthal asymmetries in SIDIS using an 11-GeV polarized electron beam from the upgraded CEBAF facility and the CLAS12 detector equipped with a transversely polarized target. The main focus of the experiment will be the measurement of transverse target single and double spin asymmetries in the reaction ep{up_arrow} -> ehX, where e is an electron, p{up_arrow} is transversely polarized proton, h is a meson (e.g., a pion or a kaon) and X is the undetected final state. The details of the conceptual design of the shielding magnetic system and transverse dipole are reported.

Statera, Marco [INFN, Ferrara (Italy); Contalbrigo, Marco M. [INFN, Ferrara (Italy); Pappalardo, Luciano Libero [INFN, Ferrara (Italy); Barion, Luca [INFN, Ferrara (Italy); Bertelli, S. [INFN, Ferrara (Italy); Ciullo, Giuseppe [INFN, Ferrara (Italy); Lenisa, Paolo [INFN, Ferrara (Italy)

2013-06-01T23:59:59.000Z

11

Search for New and Unusual Stangonia using CLAS  

SciTech Connect (OSTI)

We perform a survey of the proton, K^+, K^- -3 charged track data, taken by the CLAS detector for the HyCLAS experiment during the g12 run-period at Jefferson Lab. We aim to study the strong decay amplitudes, partial widths and production channels of strangeonia from the CLAS g12 dataset. HyCLAS was motivated by the experimental results for gluonic hybrid meson candidates, theoretical Lattice QCD, and Flux-tube Model calculations and predictions. The experiment was designed and conducted to search and observe new forms of hadronic matter through photoproduction.

Saini, Mukesh Satyapraka [Florida State U.

2013-03-01T23:59:59.000Z

12

Status of Meson Photoproduction Experiments with CLAS  

SciTech Connect (OSTI)

A large part of the experimental program in Hall B of the Jefferson Lab is dedicated to baryon spectroscopy. Meson photoproduction experiments are essential part of this program. CEBAF Large Acceptance Spectrometer (CLAS) and availability of circularly and linearly polarized tagged photon beams in combination with longitudinally and transversely polarized frozen spin targets provide unique conditions for this type of experiments. For the first time, a complete or nearly complete measurement became possible and will allow model independent extraction of the reaction amplitude. The measurements were complete with both proton and deuteron targets. An overview of the collected experimental data will be presented.

Pasyuk, Eugene A.

2014-01-01T23:59:59.000Z

13

Deeply virtual compton scattering from the neutron with CLAS and CLAS12  

SciTech Connect (OSTI)

Generalised Parton Distributions (GPDs) offer an insight into the three-dimensional structure of the nucleon and its internal dynamics, relating the longitudinal momentum of quarks to their transverse position. A very effective means of accessing GPDs is via measurements of cross-sections and polarisation-asymmetries in Deeply Virtual Compton Scattering (DVCS). In particular, the beam-spin asymmetry (BSA) in DVCS from the neutron is especially sensitive to angular momentum of the up- and down-quarks, and its measurement therefore has potential to shed important light on the puzzle of nucleon spin. We present a preliminary extraction of BSA from a recent experiment using a 6 GeV electron beam and the CLAS detector at Jefferson Laboratory and introduce the Central Neutron Detector to be integrated with CLAS12 for the exclusive measurement of neutron DVCS at 11 GeV, made possible by the Jefferson Lab upgrade.

Sokhan, Daria [Glasgow University, Glasgow, Scotland (United Kingdom)

2014-01-01T23:59:59.000Z

14

The CLAS12 large area RICH detector  

SciTech Connect (OSTI)

A large area RICH detector is being designed for the CLAS12 spectrometer as part of the 12 GeV upgrade program of the Jefferson Lab Experimental Hall-B. This detector is intended to provide excellent hadron identification from 3 GeV/c up to momenta exceeding 8 GeV/c and to be able to work at the very high design luminosity-up to 1035 cm2 s?1. Detailed feasibility studies are presented for two types of radiators, aerogel and liquid C6F14 freon, in conjunction with a highly segmented light detector in the visible wavelength range. The basic parameters of the RICH are outlined and the resulting performances, as defined by preliminary simulation studies, are reported.

M. Contalbrigo, E. Cisbani, P. Rossi

2011-05-01T23:59:59.000Z

15

Overview of the recent results from CLAS  

SciTech Connect (OSTI)

An overview of the recent results obtained at the Thomas Jefferson Laboratory on the study of the nucleon internal structure is presented, with main focus on the CLAS measurements of the Transverse Momentum Dependent partonic functions. The JLab with its CEBAF accelerator and the three experimentals halls is a Laboratory dedicated to the study of the hadronic physics with electromagnetic probes in a large variety of aspects. The physics program extends from typical nuclear effects like long range correlations in nuclei to the study of the short distance vacuum structure in parity violating experiments. In recent years, a big part of the physics program was devoted to the study of the Transverse Momentum Dependent distribution functions, new functions introduced to describe the internal structure of the nucleon. Studies of TMDs at JLab and in other laboratories have shown sizeable effects due to transverse motion of the quarks inside the nucleon, but also have open questions. These questions need to be addressed in a new generation of experiments, poviding higher precisions experimental data, and with new analysis techniques, necessary to unfold fundamental properties from the measured obsevables.

Marco Mirazita

2012-03-01T23:59:59.000Z

16

Di-hadron SIDIS measurements at CLAS  

SciTech Connect (OSTI)

Semi-inclusive deep-inelastic scattering (SIDIS) is an essential tool to probe nucleon internal structure. Through single hadron SIDIS processes, indeed, it is possible to access the TMDs, containing information on both the longitudinal and transverse motion of the partons. In recent years, moreover, an increasing attention has been devoted to dihadron SIDIS. It constitutes the golden channel to access the higher-twist collinear Parton Distribution Functions e(x) and h{sub L}(x), so far only marginally known, whose extraction will complete the collinear description of the nucleon at the twist-3 level. The CLAS detector in the Hall-B at JLab, thanks to its large acceptance, is particularly suited for such measurements. Analyses aiming at the extraction of dihadron SIDIS Beam and Target-Spin Asymmetries are presently in progress. In these proceedings, preliminary results for the Beam-Spin Asymmetry are reported, together with a summary of the dihadron SIDIS experimental program at JLab.

Pisano, Silvia [Lab. Naz. Frascati, Frascati, Italy

2014-06-01T23:59:59.000Z

17

CLAS C308 Roman Law C. J. Bannon SYLLABUS Fall 2012  

E-Print Network [OSTI]

CLAS C308 Roman Law C. J. Bannon SYLLABUS Fall 2012 Professor Cynthia J. Bannon Office: Ballantine% Research Paper 20% #12;CLAS C308 Roman Law C. J. Bannon SYLLABUS Fall 2012 Course Policies and Expectations

Indiana University

18

A ring imaging Cherenkov detector for CLAS12  

SciTech Connect (OSTI)

The energy increase of Jefferson Lab's Continuous Electron Beam Accelerator Facility (CEBAF) to 12 GeV promises to greatly extend the physics reach of its experiments. This will include an upgrade of the CEBAF Large Acceptance Spectrometer (CLAS) to CLAS12, offering unique possibilities to study internal nucleon dynamics. For this excellent hadron identification over the full kinematical range of 38 GeV/c is essential. This will be achieved by the installation of a Ring Imaging CHerenkov (RICH) detector. A novel hybrid imaging design incorporating mirrors, aerogel radiators and Hamamatsu H8500 multianode photomultiplier tubes is proposed. Depending on the incident particle track angle, Cherenkov light will either be imaged directly or after two reflections and passes through the aerogel. The detector design is described, along with preliminary results on individual detector components tests and from recent testbeam studies.

Montgomery, Rachel A. [Glasgow University

2013-12-01T23:59:59.000Z

19

Analysis of CLAS data on double charge pion electroproduction  

E-Print Network [OSTI]

Recent developments in phenomenological analysis of the CLAS data on 2$\\pi$ electroproduction are presented. The contributions from isobar channels and $P_{11}(1440)$, $D_{13}(1520)$ electrocouplings at $Q^{2}$ from 0.25 to 0.6 GeV$^2$ were determined from the analysis of comprehensive data on differential and fully integrated 2$\\pi$ cross sections. Experiment Numbers: E94-005 Group: Hall B

Viktor Mokeev; Volker Burkert; Latifa Elouadrhiri; Gleb Fedotov; Evgeny Golovach; Eugeny Isupov; Boris Ishkhanov; Nikolay Shvedunov

2007-10-31T23:59:59.000Z

20

Recent Developments for the CLAS12 Simulation G.P.Gilfoyle, M. Moog, M.Ungaro, et al.  

E-Print Network [OSTI]

of CLAS12 OTOFP1A NDE Neutron detection efficiency (NDE) needed for E12-07-104 (Gn M experiment) and others. Study first TOF panel (OTOFP1A); we have CLAS6 NDE measurements for these scintillators. NeutronV Calorimeter TOF CLAS12 Workshop - Nov 18, 2009 ­ p. 2/2 #12;Simulation of CLAS12 OTOFP1A NDE Generate `elastic

Gilfoyle, Jerry

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

A Bayesian analysis of pentaquark signals from CLAS data  

SciTech Connect (OSTI)

We examine the results of two measurements by the CLAS collaboration, one of which claimed evidence for a $\\Theta^{+}$ pentaquark, whilst the other found no such evidence. The unique feature of these two experiments was that they were performed with the same experimental setup. Using a Bayesian analysis we find that the results of the two experiments are in fact compatible with each other, but that the first measurement did not contain sufficient information to determine unambiguously the existence of a $\\Theta^{+}$. Further, we suggest a means by which the existence of a new candidate particle can be tested in a rigorous manner.

David Ireland; Bryan McKinnon; Dan Protopopescu; Pawel Ambrozewicz; Marco Anghinolfi; G. Asryan; Harutyun Avakian; H. Bagdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; V. Batourine; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Lukasz Blaszczyk; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Liam Casey; Shifeng Chen; Lu Cheng; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Volker Crede; Natalya Dashyan; Rita De Masi; Raffaella De Vita; Enzo De Sanctis; Pavel Degtiarenko; Alexandre Deur; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Lamiaa Elfassi; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Ahmed Fradi; Herbert Funsten; Michel Garcon; Gagik Gavalian; Nerses Gevorgyan; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Wesley Gohn; Atilla Gonenc; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Kawtar Hafidi; Hayk Hakobyan; Charles Hanretty; Neil Hassall; F. Hersman; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde; Yordanka Ilieva; Boris Ishkhanov; Eugeny Isupov; D. Jenkins; Hyon-Suk Jo; John Johnstone; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Mikhail Kossov; Zebulun Krahn; Laird Kramer; Valery Kubarovsky; Joachim Kuhn; Sergey Kuleshov; Viacheslav Kuznetsov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; D. Lawrence; Kenneth Livingston; Haiyun Lu; Marion MacCormick; Nikolai Markov; Paul Mattione; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Brahim Moreno; Kei Moriya; Steven Morrow; Maryam Moteabbed; Edwin Munevar Espitia; Gordon Mutchler; Pawel Nadel-Turonski; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; Kijun Park; Evgueni Pasyuk; Craig Paterson; Sergio Pereira; Joshua Pierce; Nikolay Pivnyuk; Oleg Pogorelko; Sergey Pozdnyakov; John Price; Sebastien Procureur; Yelena Prok; Brian Raue; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Dmitri Sharov; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Daria Sokhan; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; David Tedeschi; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Daniel Watts; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; M.H. Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

2008-02-01T23:59:59.000Z

22

K^*0 Photoproduction off the proton at CLAS  

E-Print Network [OSTI]

We report here differential cross sections for the reaction $\\gamma p \\to K^{*0}\\Sigma^+$ for the first time with high statistics. The measurements were done using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Data were taken at 3.115 GeV electron beam energy using tagged photons incident upon a liquid hydrogen target. In addition, our analysis provides information about nucleon resonances and their couplings to $K^*$ decay. Our data will be used to test predictions of theoretical models of K$^*$ production, and to provide constraints on the $K^*\\Sigma N$ coupling constant used in these models.

I. Hleiqawi; K. Hicks

2005-12-24T23:59:59.000Z

23

Light Baryon Spectroscopy using the CLAS Spectrometer at Jefferson Laboratory  

SciTech Connect (OSTI)

Baryons are complex systems of confined quarks and gluons and exhibit the characteristic spectra of excited states. The systematics of the baryon excitation spectrum is important to our understanding of the effective degrees of freedom underlying nucleon matter. High-energy electrons and photons are a remarkably clean probe of hadronic matter, providing a microscope for examining the nucleon and the strong nuclear force. Current experimental efforts with the CLAS spectrometer at Jefferson Laboratory utilize highly-polarized frozen-spin targets in combination with polarized photon beams. The status of the recent double-polarization experiments and some preliminary results are discussed in this contribution.

Volker Crede

2011-12-01T23:59:59.000Z

24

The RICH detector for CLAS12 at Jefferson Lab  

SciTech Connect (OSTI)

The CLAS12 spectrometer at JLab will offer unique possibilities to study the 3D nucleon structure in terms of TMDs and GPDs in the poorly explored valence region, and to perform high precision hadron spectroscopy. A large area ring-imaging Cherenkov detector has been designed to achieve the required hadron identification capability in the momentum range 3-8?GeV/c. The detector, based on a novel hybrid imaging design, foresees an aerogel radiator and an array of multi-anode photomultipliers. The detector concept and preliminary results of test-beams on a prototype are presented.

Pappalardo, Luciano L. [INFN, Ferrara, Italy

2014-06-01T23:59:59.000Z

25

Status of Hall B superconducting magnets for the CLAS12 detector at JLab  

SciTech Connect (OSTI)

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the CLAS12 detector is presented.

Quettier, L; Kashy, D; Elouadrhiri, L; Salpietro, E; Schneider, W; Small, R; Leung, E; Juang, T; McMullin, J; Taylor, C; Xu, L; Wagner, B; Wang, B; Wang, M

2011-12-01T23:59:59.000Z

26

eA Pion Production at CLAS Aimed at Neutrinos  

SciTech Connect (OSTI)

Preliminary results on semi-inclusive charged pion production in eA collisions at E{sub beam} = 5 GeV/c{sup 2} are presented. The data were collected using the CLAS detector, which is a multipurpose, large acceptance, magnetic spectrometer located in Hall B at the Thomas Jefferson National Accelerator Facility. Distributions in W, Q{sup 2}, p{sub {pi}}, and {theta}{sub {pi}} are shown for data produced using deuterium and carbon targets. Preliminary comparisons with data simulated using the GENIE generator are made. The motivation for this work is to provide distributions useful for tuning the hadronic production models used in extracting results from current and next-generation neutrino oscillation experiments.

Steven Manly

2011-11-01T23:59:59.000Z

27

Performance of the CLAS12 Silicon Vertex Tracker modules  

SciTech Connect (OSTI)

For the 12 GeV upgrade, the CLAS12 experiment has designed a Silicon Vertex Tracker (SVT) using single sided microstrip sensors fabricated by Hamamatsu. The sensors have graded angle design to minimize dead areas and a readout pitch of 156{micro}m, with intermediate strip. Double sided SVT module hosts three daisy-chained sensors on each side with a full strip length of 33 cm. There are 512 channels per module read out by four Fermilab Silicon Strip Readout (FSSR2) chips featuring data driven architecture, mounted on a rigid-flex hybrid. Modules are assembled on the barrel using unique cantilevered geometry to minimize the amount of material in the tracking volume. Design and performance of the SVT modules are presented, focusing on results of electrical measurements.

Antonioli, Mary Ann [JLAB; Boiarinov, Serguie; Bonneau, Peter R. [JLAB; Elouadrhiri, Latifa [JLAB; Eng, Brian J. [JLAB; Gotra, Yuri N. [JLAB; Kurbatov, Evgeny O. [Moscow State U.; Leffel, Mindy A. [JLAB; Mandal, Saptarshi [JLAB; McMullen, Marc E. [JLAB; Merkin, Mikhail M. [Moscow State U.; Raydo, Benjamin J. [JLAB; Teachey, Robert W, [JLAB; Tucker, Ross J. [Arizona State U.; Ungaro, Maurizio [JLAB; Yegneswaran, Amrit S. [JLAB; Ziegler, Veronique [JLAB

2013-12-01T23:59:59.000Z

28

Exclusive rho^0 electroproduction on the proton at CLAS  

SciTech Connect (OSTI)

The $e p\\to e^\\prime p \\rho^0$ reaction has been measured, using the 5.754 GeV electron beam of Jefferson Lab and the CLAS detector. This represents the largest ever set of data for this reaction in the valence region. Integrated and differential cross sections are presented. The $W$, $Q^2$ and $t$ dependences of the cross section are compared to theoretical calculations based on $t$-channel meson-exchange Regge theory on the one hand and on quark handbag diagrams related to Generalized Parton Distributions (GPDs) on the other hand. The Regge approach can describe at the $\\approx$ 30% level most of the features of the present data while the two GPD calculations that are presented in this article which succesfully reproduce the high energy data strongly underestimate the present data. The question is then raised whether this discrepancy originates from an incomplete or inexact way of modelling the GPDs or the associated hard scattering amplitude or whether the GPD formalism is simply in

Morrow, Steven; Guidal, Michel; Garcon, Michel; Laget, Jean; Smith, Elton; Adams, Gary; Adhikari, Krishna; Aghasyan, Mher; Amaryan, Moscov; Amaryan, Moskov; Anghinolfi, Marco; Asryan, G.; Audit, Gerard; Avagyan, Harutyun; Bagdasaryan, H.; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bookwalter, Craig; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Carnahan, Bryan; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dhamija, Seema; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Didelez, Jean-Pierre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Fersch, Robert; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gordon, Christopher; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hourany, E.; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Langheinrich, Jorn; Lawrence, Dave; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McCracken, Michael; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O'Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Park, Sungkyun; Pasyuk, Evgueni; Paterson, Craig; Pereira, S.Anefalos; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Polli, Ermanno; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rubin, Philip; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro

2009-01-01T23:59:59.000Z

29

Deeply virtual Compton Scattering cross section measured with CLAS  

SciTech Connect (OSTI)

The Generalized Parton Distributions (GPDs) provide a new description of nucleon structure in terms of its elementary constituents, the quarks and the gluons. Including and extending the information provided by the form factors and the parton distribution functions, they describe the correlation between the transverse position and the longitudinal momentum fraction of the partons in the nucleon. Deeply Virtual Compton Scattering (DVCS), the electroproduction of a real photon on a single quark in the nucleon eN --> e'N'g, is the exclusive process most directly interpretable in terms of GPDs. A dedicated experiment to study DVCS with the CLAS detector at Jefferson Lab has been carried out using a 5.9-GeV polarized electron beam and an unpolarized hydrogen target, allowing us to collect DVCS events in the widest kinematic range ever explored in the valence region : 1.0 < Q2 < 4.6 GeV2, 0.1 < xB < 0.58 and 0.09 < -t < 2.0 GeV2. In this paper, we show preliminary results of unpolarized cross sections and of polarized cross section differences for the DVCS channel.

Guegan, Baptistse [Institut de Physique Nucleaire, Orsay

2014-09-01T23:59:59.000Z

30

Hall B superconducting magnets for the CLAS12 detector at JLAB  

SciTech Connect (OSTI)

Hadron physics has been an essential part of the physics program with the CLAS detector in experimental hall B at Thomas Jefferson National Accelerator Facility (Jefferson Lab). With the 12 GeV upgrade of the CEBAF machine, hadron physics in Hall B will be extended to a new domain of higher mass resonances and the range of higher transferred momentum using up to 11 GeV electron beams and the upgraded CLAS12 detector. In this paper, status of the hall B superconducting magnets for the 12 GeV upgrade is presented.

L. Quettier, V. Burkert, L. Elouadrhiri, D. Kashy, E. Leung, W. Schneider

2011-02-01T23:59:59.000Z

31

Phenomenological analysis of the CLAS data on double charged pion photo and electro- production  

SciTech Connect (OSTI)

First comprehensive data on the evolution of nucleon resonance photocouplings with photon virtuality Q{sup 2} are presented for excited proton states in the mass range from 1.4 to 2.0 GeV. N* photocouplings were determined in phenomenological analysis of CLAS data on 2 pi photo and electroproduction within the framework of the JLAB-MSU phenomenological model.

Viktor Mokeev; Volker Burkert; Latifa Elouadrhiri; A.A. Boluchevsky; Gleb Fedotov; Eugeny Isupov; Boris Ishkhanov; Nikolay Shvedunov

2005-10-01T23:59:59.000Z

32

Report on CLAS12 Software Workshop Broad view of the state-of-the-art in  

E-Print Network [OSTI]

, RHIC and Atlas Computing Facility Relativistic Heavy-Ion Collider (RHIC). Formation of quark Ernst, Director, RHIC and Atlas Computing Facility Data Formats CLAS Collaboration Meeting, June 17 Michael Ernst, Director, RHIC and Atlas Computing Facility Parallel processing. Done with athenaMP. Single

Gilfoyle, Jerry

33

Gerasimov-Drell-Hearn Sum Rule and the Discrepancy between the New CLAS and SAPHIR Data  

E-Print Network [OSTI]

Contribution of the K^+\\Lambda channel to the Gerasimov-Drell-Hearn (GDH) sum rule has been calculated by using the models that fit the recent SAPHIR or CLAS differential cross section data. It is shown that the two data sets yield quite different contributions. Contribution of this channel to the forward spin polarizability of the proton has been also calculated. It is also shown that the inclusion of the recent CLAS C_x and C_z data in the fitting data base does not significantly change the result of the present calculation. Results of the fit, however, reveal the role of the S_{11}(1650), P_{11}(1710), P_{13}(1720), and P_{13}(1900) resonances for the description of the C_x and C_z data. A brief discussion on the importance of these resonances is given. Measurements of the polarized total cross section \\sigma_{TT'} by the CLAS, LEPS, and MAMI collaborations are expected to verify this finding.

T. Mart

2008-03-05T23:59:59.000Z

34

A new measurement of Beam Asymmetry in Pion Photoproduction from the Neutron using CLAS  

SciTech Connect (OSTI)

We present a preliminary analysis of the photon beam asymmetry observable (Sigma) from the photoproduction reaction channel gamma+ n -> p + pi-. This new data was obtained using the near-4pi CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory, USA, employing a linearly polarised photon beam with an energy range 1.1 - 2.3 GeV. The measurement will provide new data to address the poorly established neutron excitation spectrum and will greatly expand the sparse world data-set both in energy and angle.

D. Sokhan, D. Watts, D. Branford, F. Klein

2010-08-01T23:59:59.000Z

35

Studies of 3D structure of the nucleon with CLAS at Jlab  

SciTech Connect (OSTI)

Studies of single-spin asymmetries in pions electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized and polarized targets, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility, are presented. A substantial sin phih amplitude has been measured in the the cross section as a function of the azimuthal angle phih of the produced neutral pion. The dependence of this amplitude on Bjorken x and on the pion transverse momentum has been extracted with significantly higher precision than previous data and is compared to model calculations.

Mher Aghasyan

2011-12-01T23:59:59.000Z

36

Studies of 3D structure of the nucleon with CLAS at JLab  

SciTech Connect (OSTI)

Studies of single-spin asymmetries in pions electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized and polarized targets, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility, are presented. A substantial sin {phi}{sub h} amplitude has been measured in the the cross section as a function of the azimuthal angle {phi}{sub h} of the produced neutral pion. The dependence of this amplitude on Bjorken x and on the pion transverse momentum has been extracted with significantly higher precision than previous data and is compared to model calculations.

Aghasyan, Mher [INFN, Laboratori Nazionali di Frascati, 00044 Frascati (Italy); Collaboration: CLAS Collaboration

2011-12-14T23:59:59.000Z

37

Studies of N*#3; Structure from the CLAS Meson Electroproduction Data  

SciTech Connect (OSTI)

The transition {gamma}{sub v}pN#3; amplitudes (electrocouplings) for prominent excited nucleon states obtained in a wide area of photon virtualities offer valuable information for the exploration of the N#3; structure at different distances and allow us to access the complex dynamics of non-perturbative strong interaction. The current status in the studies of {gamma}{sub v}pN#3; electrocouplings from the data on exclusive meson electroproduction off protons measured with the CLAS detector at Jefferson Lab is presented. The impact of these results on exploration of the N#3; structure is discussed.

Mokeev, Viktor I. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Aznauryan, Inna G. [Yerevan Physics Institute, Yerevan (Armenia)

2014-01-01T23:59:59.000Z

38

Deep exclusive {pi}{sup +} electroproduction off the proton at CLAS  

SciTech Connect (OSTI)

The exclusive electroproduction of {pi}{sup +} above the resonance region was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Laboratory by scattering a 6 GeV continuous electron beam off a hydrogen target. The large acceptance and good resolution of CLAS, together with the high luminosity, allowed us to measure the cross section for the {gamma}* p {yields} n {pi}{sup +} process in 140 (Q{sup 2}, x{sub B}, t) bins: 0.16

Park, Kijun; Gothe, Ralf; Guidal, Michel; Laget, Jean; Adhikari, K P; Bennet, R P; Biselli, A S; Chandavar, S; MacGregor, I. J. D; Munoz Camacho, C; Anefalos-Pereira, S; Rimal, D; Tang, W

2013-01-01T23:59:59.000Z

39

Search for the Theta+ pentaquark in the gamma d -> Lambda n K+ reaction measured with CLAS  

SciTech Connect (OSTI)

For the first time, the reaction gamma d -> Lambda n K+ has been analyzed in order to search for the exotic pentaquark baryon Theta+(1540). The data were taken at Jefferson Lab, using the Hall-B tagged-photon beam of energy between 0.8 and 3.6 GeV and the CEBAF Large Acceptance Spectrometer (CLAS). No statistically significant structures were observed in the nK+ invariant mass distribution. The upper limit on the gamma d -> Lambda Theta+ integrated cross section has been calculated and found to be between 5 and 25 nb, depending on the production model assumed. The upper limit on the differential cross section is also reported.

Silvia Niccolai; Marco Mirazita; Patrizia Rossi; Nathan Baltzell; Daniel Carman; Kenneth Hicks; Bryan McKinnon; Tsutomu Mibe; Stepan Stepanyan; David Tedeschi; Gary Adams; Pawel Ambrozewicz; Sergio Pereira; Marco Anghinolfi; Gegham Asryan; Harutyun AVAKIAN; H. Bagdasaryan; Nathan Baillie; Jacques Ball; V. Batourine; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Sergey Boyarinov; Sylvain Bouchigny; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; S.L. Careccia; Bryan Carnahan; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; V. Crede; John Cummings; Natalya Dashyan; Pavel Degtiarenko; Rita De Masi; Airton Deppman; Enzo De Sanctis; Alexandre Deur; Raffaella De Vita; Kahanawita Dharmawardane; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; L. El Fassi; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; John Hardie; F. Hersman; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mikhail Kossov; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Kenneth Livingston; H. Lu; Marion MacCormick; Nikolai Markov; Bernhard Mecking; Jonathan Mellor; Joseph Melone; Mac Mestayer; Curtis Meyer; Konstantin Mikhaylov; Ralph Minehart; Rory Miskimen; Viktor Mokeev; Ludyvine Morand; Steven Morrow; Maryam Moteabbed; Gordon Mutchler; Pawel Nadel-Turonski; James Napolitano; Rakhsha Nasseripour; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Jorge De Olivei Echeimberg; Mikhail Osipenko; Alexander Ostrovidov; K. Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Sergey Pozdnyakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Igor Strakovski; Steffen Strauch; Mauro Taiuti; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Daniel Watts; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

2006-04-26T23:59:59.000Z

40

Coherent photoproduction of {pi}{sup +} from {sup 3}He with CLAS at Jefferson Lab  

SciTech Connect (OSTI)

We have measured the differential cross section for the {gamma}{sup 3}He{yields}{pi}{sup +}t reaction. This reaction was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B bremsstrahlung tagging system in the energy range from 0.5 to 1.55 GeV were incident on a cryogenic liquid {sup 3}He target. The differential cross sections for the {gamma}{sup 3}He{yields}{pi}{sup +}t reaction were measured as a function of photon-beam energy and pion-scattering angle. Theoretical predictions to date cannot explain the large cross sections except at backward angles, showing that additional components must be added to the model.

Nasseripour, Rakhsha; Berman, Barry [George Washington University, Washington, DC 20052 (United States)

2011-10-24T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Coherent photoproduction of pi+ from He-3 with CLAS at Jefferson Laboratory  

SciTech Connect (OSTI)

We have measured the differential cross section for the {gamma}{sup 3}He {yields} t{pi}{sup +} reaction. This reaction was studied using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. Real photons produced with the Hall-B bremsstrahlung tagging system in the energy range from 0.5 to 1.55 GeV were incident on a cryogenic liquid {sup 3}He target. The differential cross sections for the {gamma}{sup 3}He {yields} i{pi}{sup +}t reaction were measured as a function of photon-beam energy and pion-scattering angle Theoretical predictions to date cannot explain the large cross sections except at backward angles, showing that additional components must be added to the model.

Rakhsha Nasseripour, Barry Berman

2011-09-01T23:59:59.000Z

42

Exclusive pi^0 electroproduction at W > 2 GeV with CLAS  

SciTech Connect (OSTI)

Exclusive neutral-pion electroproduction (ep-->e'p'pi0) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4sigma/dtdQ2dxBdphipi and structure functions sigmaT+epsilonsigmaL,sigmaTT and ?LT as functions of t were obtained over a wide range of Q2 and xB. The data are compared with Regge and handbag theoretical calculations. Analyses in both frameworks find that a large dominance of transverse processes is necessary to explain the experimental results. For the Regge analysis it is found that the inclusion of vector meson rescattering processes is necessary to bring the magnitude of the calculated and measured structure functions into rough agreement. In the handbag framework, there are two independent calculations, both of which appear to roughly explain the magnitude of the structure functions in terms of transversity generalized parton distributions.

Bedlinskiy, I.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K.P.; Anderson, M.D.; Pereira, S. Anefalos; Avakian, H.; Ball, J.; Baltzell, N.A.; Battaglieri, M.; Batourine, V.; Biselli, A.S.; Boiarinov, S.; Bono, J.; Briscoe, W.J.; Brooks, W.K.; Burkert, V.D.; Carman, D.S.; Celentano, A.; Chandavar, S.; Colaneri, L.; Cole, P.L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J.A.; Forest, T.A.; Garillon, B.; Garcon, M.; Gavalian, G.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G.P.; Giovanetti, K.L.; Girod, F.X.; Golovatch, E.; Gothe, R.W.; Griffioen, K.A.; Guegan, B.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Ireland, D.G.; Ishkhanov, B.S.; Isupov, E.L.; Jenkins, D.; Jo, H.S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F.J.; Koirala, S.; Kuhn, S.E.; Kuleshov, S.V.; Lenisa, P.; Levine, W.I.; Livingston, K.; Lu, H.Y.; MacGregor, I.J.D.; Markov, N.; Mayer, M.; McKinnon, B.; Mirazita, M.; Mokeev, V.; Montgomery, R.A.; Moody, C.I.; Moutarde, H.; Movsisyan, A; Munoz Camacho, C.; Nadel-Turonski, P.; Niculescu, I.; Osipenko, M.; Ostrovidov, A.I.; Pappalardo, L.L.; Park, K.; Park, S.; Pasyuk, E.; Phelps, E.; Phelps, W.; Phillips, J.J.; Pisano, S.; Pogorelko, O.; Price, J.W.; Prok, Y.; Protopopescu, D.; Procureur, S.; Puckett, A.J.R.; Raue, B.A.; Ripani, M.; Ritchie, B.G.; Rizzo, A.; Rossi, P.; Roy, P.; Sabati, F.; Salgado, C.; Schott, D.; Schumacher, R.A.; Seder, E.; Senderovich, I.; Sharabian, Y.G.; Simonyan, A.; Smith, G.D.; Sober, D.I.; Sokhan, D.; Stepanyan, S.S.; Strauch, S.; Sytnik, V.; Tang, W.; Tian, Ye; Ungaro, M.; Vlassov, A.V.; Voskanyan, H.; Voutier, E.; Walford, N.K.; Watts, D.; Wei, X.; Weinstein, L.B.; Yurov, M.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z.W.; Zonta, I.

2014-08-01T23:59:59.000Z

43

Measurement of the nuclear multiplicity ratio or image hadronization at CLAS  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The influence of cold nuclear matter on lepto-production of hadrons in semi-inclusive deep inelastic scattering is measured using the CLAS detector in Hall B at Jefferson Lab and a 5.014 GeV electron beam. We report the View the MathML source multiplicity ratios for targets of C, Fe, and Pb relative to deuterium as a function of the fractional virtual photon energy z transferred to the View the MathML source and the transverse momentum squared View the MathML source of the View the MathML source. We find that the multiplicity ratios for View the MathML source are reduced in the nuclear medium at high z and low View the MathML source, with a trend for the View the MathML source transverse momentum to be broadened in the nucleus for large View the MathML source.

Daniel, A; Brooks, W K; Hakobyan, H; Adhikari, K P; Adikaram, D; Aghasyan, M; Amarian, M; Anghinolfi, M; Avakian, H; Baghdasryan, H; Battaglieri, M; Batourine, V; Bedlinskiy, I; Bennett, R P; Biselli, A S; Bookwalter, C; Briscoe, W J; Burkert, V D; Carman, D S; Casey, L; Celentanot, A; Chandavar, S; Cole, P L; Contalbrigo, M; Crede, V; D' Angelou, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Dey, B; Dickson, R; Djalali, C; Dodge, G E; Doughty, D; Egiyan, H; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Golovatch, E; Gothe, R W; Griffioen, K A; Guidal, M; Guo, L; Hanretty, C; Heddle, D; Holtrop, M; Hyde, C E; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jawalkar, S S; Jo, H S; Joo, K; Kalantarian, N; Keller, D; Khandaker, M; Khetarpal, P; Kim, A; Kim, W; Klein, A; Klein, F J; Kubarovsky, V; Kuleshov, S V; Kuznetsov, V; Lu, H Y; MacGregor, I.J.D.; Mao, Y; Markov, N; Mayer, M; McAndrew, J; McKinnon, B; Meyer, C A; Mine, T; Mirazita, M; Mokeev, V; Moutard, H; Munevar, E; Nadel-Turonski, P; Ni, A; Niccolai, S; Niculescux, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardor, L; Paremuzyan, R; Park, K; Pasyuk, E; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Protopopescu, D; Rauem, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, G D; Soberg, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tkachenko, S; Ungaro, M; Vernarsky, B; Vineyard, M F; Voskanyan, H; Voutier, E; Watts, D P; Weinstein, L B; Weygand, D P; Wood, M H; Zana, L; Zachario, N; Zhao, B

2011-11-30T23:59:59.000Z

44

The large-area hybrid-optics CLAS12 RICH detector: Tests of innovative components  

SciTech Connect (OSTI)

A large area ring-imaging Cherenkov detector has been designed to provide clean hadron identification capability in the momentum range from 3 GeV/c to 8 GeV/c for the CLAS12 experiments at the upgraded 12 GeV continuous electron beam accelerator facility of Jefferson Lab to study the 3D nucleon structure in the yet poorly explored valence region by deep-inelastic scattering, and to perform precision measurements in hadronization and hadron spectroscopy. The adopted solution foresees a novel hybrid optics design based on an aerogel radiator, composite mirrors and densely packed and highly segmented photon detectors. Cherenkov light will either be imaged directly (forward tracks) or after two mirror reflections (large angle tracks). The preliminary results of individual detector component tests and of the prototype performance at test-beams are reported here.

Contalbrigo, M.; Baltzell, N.; Benmokhtar, F.; Barion, L.; Cisbani, E.; El Alaoui, A.; Hafidi, K.; Hoek, M.; Kubarovsky, V.; Lagamba, L.; Lucherini, V.; Malaguti, R.; Mirazita, M.; Montgomery, R.; Movsisyan, A.; Musico, P.; Orecchini, D.; Orlandi, A.; Pappalardo, L.L.; Pereira, S.; Perrino, R.; Phillips, J.; Pisano, S.; Rossi, P.; Squerzanti, S.; Tomassini, S.; Turisini, M.; Viticchi, A.

2014-07-01T23:59:59.000Z

45

Electroproduction of $\\phi(1020)$ Mesons at High $Q^2$ with CLAS  

SciTech Connect (OSTI)

http://dx.doi.org/10.1103/PhysRevC.78.025210
Electroproduction of exclusive $\\phi$ vector mesons has been studied with the CLAS detector in the kinematical range $1.6\\leq Q^2\\leq 3.8$ GeV$^{2}$, $0.0\\leq t^{\\prime}\\leq 3.6$ GeV$^{2}$, and $2.0\\leq W\\leq 3.0$ GeV. The scaling exponent for the total cross section as $1/(Q^2+M_{\\phi}^2)^n$ was determined to be $n=2.49\\pm 0.33$. The slope of the four-momentum transfer $t'$ distribution is $b_{\\phi}=0.98 \\pm 0.17$ GeV$^{-2}$. The data are consistent with the assumption of s-channel helicity conservation (SCHC). Under this assumption, we determine the ratio of longitudinal to transverse cross sections to be $R=0.86 \\pm 0.24$. A 2-gluon exchange model is able to reproduce the main features of the data.

Santoro, Joseph; Smith, Elton; Garcon, Michel; Guidal, Michel; Laget, Jean; Weiss, Christian; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Anghinolfi, Marco; Asryan, Gegham; Audit, Gerard; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, James; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bookwalter, Craig; Bouchigny, Sylvain; Bouchigny, Sylvain; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Sanctis, Enzo; De Vita, Raffaella; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dhamija, Seema; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feuerbach, Robert; Ficenec, John; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gordon, Christopher; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Langheinrich, Jorn; Lawrence, David; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O'Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Park, Sungkyun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, A

2008-08-01T23:59:59.000Z

46

Beyond the born approximation: Measuring the two-photon exchange effect at CLAS  

SciTech Connect (OSTI)

Recent results from experiments at Jefferson Laboratory, Newport News VA, which measured the ratio of the electric to magnetic form factors of the proton, G{sub E}/G{sub M}, have forced us to reexamine the single photon exchange approximation in lepton-proton elastic scattering. Discrepancies between the ratio obtained via the time-tested Rosenbluth separation method and newer polarization transfer measurements, which differ by as much as a factor of three, may be resolved by considering the effect of two photon exchange (TPE) processes. The CLAS TPE experiment at Jefferson Laboratory, will determine the effect of two-photon exchange in elastic lepton-proton scattering by precisely measuring the ratio of positron-proton to electron-proton elastic cross sections over a large kinematic range (0.1 < {xi} < 0.96, 0.2 {ge} Q{sup 2} {le} 2.0 GeV{sup 2}). We accomplish this by directing the 5.5 GeV primary electron beam, provided by the Continuous Electron Beam Accelerator Facility (CEBAF), onto a set of radiators and converters to produce simultaneous and identical beams of electron and positrons which collide with our proton target. Acceptance and efficiency concerns are minimized by only considering the ratios of the elastic cross sections and by switching polarity of magnets in the beamline and the spectrometer. Guided by the results of a short 2006 test run and extensive GEANT based modeling, new shielding and beamline components were designed to maximize luminosity. We took data from November 2010 - February 2011. The unique experimental design and challenges of the TPE experiment and the current analysis status will be presented.

Robert Paul Bennett

2012-04-01T23:59:59.000Z

47

Differential cross section and recoil polarization measurements for the gamma p to K+ Lambda reaction using CLAS at Jefferson Lab  

E-Print Network [OSTI]

We present measurements of the differential cross section and Lambda recoil polarization for the gamma p to K+ Lambda reaction made using the CLAS detector at Jefferson Lab. These measurements cover the center-of-mass energy range from 1.62 to 2.84 GeV and a wide range of center-of-mass K+ production angles. Independent analyses were performed using the K+ p pi- and K+ p (missing pi -) final-state topologies; results from these analyses were found to exhibit good agreement. These differential cross section measurements show excellent agreement with previous CLAS and LEPS results and offer increased precision and a 300 MeV increase in energy coverage. The recoil polarization data agree well with previous results and offer a large increase in precision and a 500 MeV extension in energy range. The increased center-of-mass energy range that these data represent will allow for independent study of non-resonant K+ Lambda photoproduction mechanisms at all production angles.

M. E. McCracken; M. Bellis; C. A. Meyer; M. Williams; for the CLAS Collaboration

2009-12-23T23:59:59.000Z

48

Single and double spin asymmetries for deeply virtual Compton scattering measured with CLAS and a longitudinally polarized proton target  

E-Print Network [OSTI]

Single-beam, single-target, and double-spin asymmetries for hard exclusive photon production on the proton $\\vec{e}\\vec{p} \\to e' p'\\gamma$ are presented. The data were taken at Jefferson Lab using the CLAS detector and a longitudinally polarized ${}^{14}$NH$_3$ target. The three asymmetries were measured in 165 4-dimensional kinematic bins, covering the widest kinematic range ever explored simultaneously for beam and target-polarization observables in the valence quark region. The kinematic dependences of the obtained asymmetries are discussed and compared to the predictions of models of Generalized Parton Distributions. The measurement of three DVCS spin observables at the same kinematic points allows a quasi-model-independent extraction of the imaginary parts of the $H$ and $\\tilde{H}$ Compton Form Factors, which give insight into the electric and axial charge distributions of valence quarks in the proton.

S. Pisano; A. Biselli; S. Niccolai; E. Seder; M. Guidal; M. Mirazita; the CLAS Collaboration

2015-01-28T23:59:59.000Z

49

The Search for Exotic Mesons in gamma p -> pi+pi+pi-n with CLAS at Jefferson Lab  

SciTech Connect (OSTI)

The {pi}{sub 1}(1600), a J{sup PC} = 1{sup {-+}} exotic meson has been observed by experiments using pion beams. Theorists predict that photon beams could produce gluonic hybrid mesons, of which the {pi}{sub 1}(1600) is a candidate, at enhanced levels relative to pion beams. The g12 rungroup at Jefferson Lab's CEBAF Large Acceptance Spectrometer (CLAS) has recently acquired a large photoproduction dataset, using a liquid hydrogen target and tagged photons from a 5.71 GeV electron beam. A partial-wave analysis of 502K {gamma}p {yields} {pi}{sup +}{pi}{sup +}{pi}{sup -}n events selected from the g12 dataset has been performed, and preliminary fit results show strong evidence for well-known states such as the a{sub 1}(1260), a{sub 2}(1320), and {pi}{sub 2}(1670). However, we observe no evidence for the production of the {pi}{sub 1}(1600) in either the partial-wave intensities or the relative complex phase between the 1{sup {-+}} and the 2{sup {-+}} (corresponding to the {pi}{sub 2}) partial waves.

Craig Bookwalter

2011-12-01T23:59:59.000Z

50

First measurements of the {rho}{sup 3} spin density matrix elements in {gamma}p --> p {omega} using CLAS at JLAB  

SciTech Connect (OSTI)

In an effort towards a ''complete'' experiment for the ? meson, we present studies from an experiment with an unpolarized target and a circularly polarized photon beam (g1c), carried out using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The experiment was analyzed using an extended maximum likelihood fit with partial wave amplitudes. New likelihood functions were calculated to account for the polarization of the photon beam. Both circular and linear polarizations are explored. The results of these fits are then used to project out the spin density matrix for the {omega}. First measurements of the {rho}{sup 3} spin density matrix elements will be presented using this method.

Vernarsky, Brian J. [Carnegie Mellon University, Pittsburgh, PA (United States)

2014-01-01T23:59:59.000Z

51

Exclusive single pion electroproduction off the proton in the high-lying resonances at Q2 < 5 GeV2 from CLAS  

SciTech Connect (OSTI)

The differential cross sections and structure functions for the exclusive electroproduction process ep --> e'n pi+ were measured in the range of the invariantmass for the np+ system 1.6 GeV lte W lte 2.0 GeV, and the photon virtuality 1.8 GeV2 lte Q2 lte 4.0 GeV2 using CLAS at Jefferson Lab. For the first time, these kinematics are probed in the exclusive p+ production from the protons with nearly full coverage in the azimuthal and polar angles of the np+ center-of-mass system. In this analysis, approximately 39,000 differential cross-section data points in terms of W, Q2, cosq theta* _ pi, and phi?_p-, were obtained. The preliminary differential cross section and structure function analyses are carried out, which allow us to extract the helicity amplitudes in high-lying resonances.

Park, Kijun [ODU, JLAB

2014-09-01T23:59:59.000Z

52

MULTISCALE RANDOM PROJECTIONS FOR COMPRESSIVE CLASSIFICATION Marco F. Duarte,r  

E-Print Network [OSTI]

of sam- pling and compression [1, 2]. CS enables the design of new kinds of compressive imaging systems ratio test; in the case of image classification, it exploits the fact that a set of images of a fixed- quires compressive image projections, we achieve high clas- sification rates using many fewer

53

APPLICATION OF THE FUZZY MINMAX NEURAL NETWORK CLASSIFIER  

E-Print Network [OSTI]

. The fuzzy min­max classification network constitutes a promisimg pattern recognition approach that is based. Experimental results us­ ing the modified model on a difficult pattern recognition prob­ lem establishes of the fuzzy min­max clas­ sification neural network on a pattern recognition problem that involves both

Blekas, Konstantinos

54

NeuDetect: A Neural Network Data Mining Wireless Network Intrusion Detection System  

E-Print Network [OSTI]

NeuDetect: A Neural Network Data Mining Wireless Network Intrusion Detection System C.I. Ezeife wireless intrusion detection systems, this paper presents a method of applying artificial neural networks mining clas- sification technique to wireless network intrusion detection system. The proposed system

Ezeife, Christie

55

Metadata Enrichment Services for the Europeana Digital Library  

E-Print Network [OSTI]

needs, thus allowing the tool to be effectively available to the multitude (2000+) of Europeana CPs. 1 to enrich the semantics of its own MRs prior to contributing them to Europeana. Different CPs are thus provenance. We view metadata enrichment as consisting of essentially two activities: clas- sification of MRs

Sebastiani, Fabrizio

56

We have designed our algorithm to extract ridge and rubble features in multiyear ice. It has been developed for use with low-  

E-Print Network [OSTI]

We have designed our algorithm to extract ridge and rubble features in multiyear ice. It has been the corresponding data prod- uct derived with the ice-roughness algorithm. We note that the algorithm was developed-of-sample. The boxed area shown in both these figures corresponds to the ice clas- sification map shown in Figure 1c

Fernandez, Thomas

57

Dynamical Systems and Applications of Nonlinear Functional Analysis to Dynamical Systems  

E-Print Network [OSTI]

Dynamical Systems and Applications of Nonlinear Functional Analysis to Dynamical Systems Meirong consists of three parts. In Part 1 we introduce some basic concepts in dynamical systems, including limit sets, nonwandering sets, topological conjugacy, clas- sification of discrete dynamical systems under

Zhang, Meirong

58

Measurement of the structure function of the nearly free neutron using spectator tagging in inelastic $^2$H(e, e'p)X scattering with CLAS  

E-Print Network [OSTI]

Much less is known about neutron structure than that of the proton due to the absence of free neutron targets. Neutron information is usually extracted from data on nuclear targets such as deuterium, requiring corrections for nuclear binding and nucleon off-shell effects. These corrections are model dependent and have significant uncertainties, especially for large values of the Bjorken scaling variable x. The Barely Off-shell Nucleon Structure (BONuS) experiment at Jefferson Lab measured the inelastic electron deuteron scattering cross section, tagging spectator protons in coincidence with the scattered electrons. This method reduces nuclear binding uncertainties significantly and has allowed for the first time a (nearly) model independent extraction of the neutron structure function. A novel compact radial time projection chamber was built to detect protons with momentum between 70 and 150 MeV/c. For the extraction of the free neutron structure function $F_{2n}$, spectator protons at backward angle and with momenta below 100 MeV/c were selected, ensuring that the scattering took place on a nearly free neutron. The scattered electrons were detected with Jefferson Lab's CLAS spectrometer. The extracted neutron structure function $F_{2n}$ and its ratio to the deuteron structure function $F_{2d}$ are presented in both the resonance and deep inelastic regions. The dependence of the cross section on the spectator proton momentum and angle is investigated, and tests of the spectator mechanism for different kinematics are performed. Our data set can be used to study neutron resonance excitations, test quark hadron duality in the neutron, develop more precise parametrizations of structure functions, as well as investigate binding effects (including possible mechanisms for the nuclear EMC effect) and provide a first glimpse of the asymptotic behavior of d/u as x goes to 1.

S. Tkachenko; N. Baillie; S. E. Kuhn; J. Zhang; J. Arrington; P. Bosted; S. Bltmann; M. E. Christy; D. Dutta; R. Ent; H. Fenker; K. A. Griffioen; M. Ispiryan; N. Kalantarians; C. E. Keppel; W. Melnitchouk; V. Tvaskis; K. P. Adhikari; M. Aghasyan; M. J. Amaryan; S. Anefalos Pereira; H. Avakian; J. Ball; N. A. Baltzell; M. Battaglieri; I. Bedlinskiy; A. S. Biselli; W. J. Briscoe; W. K. Brooks; V. D. Burkert; D. S. Carman; A. Celentano; S. Chandavar; G. Charles; P. L. Cole; M. Contalbrigo; O. Cortes; V. Crede; A. D'Angelo; N. Dashyan; R. De Vita; E. De Sanctis; A. Deur; C. Djalali; G. E. Dodge; D. Doughty; R. Dupre; H. Egiyan; A. El Alaoui; L. El Fassi; L. Elouadrhiri; P. Eugenio; G. Fedotov; J. A. Fleming; B. Garillon; N. Gevorgyan; Y. Ghandilyan; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; J. T. Goetz; E. Golovatch; R. W. Gothe; M. Guidal; L. Guo; K. Hafidi; H. Hakobyan; C. Hanretty; N. Harrison; M. Hattawy; K. Hicks; D. Ho; M. Holtrop; C . E. Hyde; Y. Ilieva; D. G. Ireland; B. S. Ishkhanov; H. S. Jo; D. Keller; M. Khandaker; A. Kim; W. Kim; A. Klein; F. J. Klein; S. Koirala; V. Kubarovsky; S. V. Kuleshov; P. Lenisa; S. Lewis; K. Livingston; H. Lu; M. MacCormick; I. J. D. MacGregor; N. Markov; M. Mayer; B. McKinnon; T. Mineeva; M. Mirazita; V. Mokeev; R. A. Montgomery; H. Moutarde; C. Munoz Camacho; P. Nadel-Turonski; S. Niccolai; G. Niculescu; I. Niculescu; M. Osipenko; L. L. Pappalardo; R. Paremuzyan; K. Park; E. Pasyuk; J. J. Phillips; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; D. Protopopescu; A. J . R. Puckett; D. Rimal; M. Ripani; A. Rizzo; G. Rosner; P. Rossi; P. Roy; F. Sabati; D. Schott; R. A. Schumacher; E. Seder; I. Senderovich; Y. G. Sharabian; A. Simonyan; G. D. Smith; D. I. Sober; D. Sokhan; S. Stepanyan; S. S. Stepanyan; S. Strauch; W. Tang; M. Ungaro; A. V. Vlassov; H. Voskanyan; E. Voutier; N. K. Walford; D. Watts; X. Wei; L. B. Weinstein; M. H. Wood; L. Zana; I. Zonta

2014-10-03T23:59:59.000Z

59

Transition Form Factor from CLAS  

SciTech Connect (OSTI)

The excitation of nucleon resonances in electromagnetic interaction has long been studied. The study of resonances helps us to understand the long- and short- range structures of the nucleon and its excited states in terms of quark confinement. While the existing data of the low-lying resonances are consistent with the well-studied SU(6) circle times operator O(3) constituent quark model classification, many open questions still remain. Exclusive electro-production is one of the best ways to investigate nucleon resonances. The exclusive electro-production process View the MathML source was measured in the photon virtuality range Q2 = 1.7 4.5 GeV2 and the invariant mass range for the n?+ system of W = 1.15 1.7 GeV using the CEBAF Large Acceptance Spectrometer. For the first time, these kinematics are probed in exclusive ?+ production from protons with nearly full coverage in the azimuthal and polar angles of the n?+ center-of-mass system. The n?+ channel has particular sensitivity t

Park, Kijun

2009-01-01T23:59:59.000Z

60

Electroproduction of ppi+pi- off protons at 0.2CLAS.  

SciTech Connect (OSTI)

This paper reports on the most comprehensive data set obtained on differential and fully integrated cross sections for the process $e p \\rightarrow e' p \\pi^{+} \\pi^{-} $. The data were collected with the CLAS detector at Jefferson Laboratory. Measurements were carried out in the so-far unexplored kinematic region of photon virtuality 0.2 $<$ $Q^{2}$ $<$ 0.6 GeV$^{2}$ and invariant mass of the final hadron system $W$ from 1.3 to 1.57~GeV. For the first time, nine independent 1-fold differential cross sections were determined in each bin of $W$ and $Q^{2}$ covered by the measurements. A phenomenological analysis of the data allowed us to establish the most significant mechanisms contributing to the reaction. The non-resonant mechanisms account for a major part of cross-sections. However, we find sensitivity to s-channel excitations of low-mass nucleon resonances, especially to the $N(1440)P_{11}$ and $N(1520)D_{13}$ states in kinematical dependencies of the 1-fold

Fedotov, Gleb; Mokeev, Viktor; Burkert, Volker; Elouadrhiri, Latifa; Golovach, Evgeny; Ishkhanov, Boris; Isupov, Evgeny; Shvedunov, Nikolay

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Extracting TMDs from CLAS12 data  

SciTech Connect (OSTI)

We present studies of double longitudinal spin asymmetries in semi-inclusive deep inelastic scattering using a new dedicated Monte Carlo generator, which includes quark intrinsic transverse momentum within the generalized parton model based on the fully differential cross section for the process. Additionally we employ Bessel-weighting to the MC events to extract transverse momentum dependent parton distribution functions and also discuss possible uncertainties due to kinematic correlation effects.

Aghasyan, Mher M. [INFN-Frascati (Italy); Avakian, Harut A. [JLAB, Newport News, VA (United States)

2014-01-01T23:59:59.000Z

62

THE CENTER FOR LATIN AMERICAN STUDIES (CLAS),  

E-Print Network [OSTI]

de ascenden- cia Latinoamericana que vivían en la región, esto resultaría en una relación mutualmente

Machery, Edouard

63

CEBAF Large Acceptance Spectrometer (CLAS) Physics Database  

DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

A username and password are required to access and search the entire database. However, the Overview page provides links to detailed data pages for each of the experiments available for public access. There are many experiments with data that the public can freely access.

64

Beam-Spin Asymmetry Measurement at CLAS  

SciTech Connect (OSTI)

Beam Single Spin Asymmetries in single neutral semi-inclusive pion electroproduction off an unpolarized hydrogen target in the deep inelastic scattering regime (Q{sup 2}>1 GeV{sup 2}, W{sup 2}>4 GeV{sup 2}) have been measured using a polarized electron beam of 5.776 GeV with the CEBAF Large Acceptance Spectrometer at the Thomas Jefferson National Accelerator Facility (JLab). The measured kinematical dependences are compared with published data and existing theoretical predictions.

Aghasyan, M

2009-08-04T23:59:59.000Z

65

Baryon spectroscopy with CLAS at Jefferson Lab  

SciTech Connect (OSTI)

A substantial part of the experimental efforts at the experimental Hall-B of Jefferson Laboratory is dedicated to this studies of light baryon spectroscopy. In this report a general overview of the experimental capabilities in the Experimental Hall-B will be presented together with preliminary results of recent double polarization measurements and finally overall status of the program.

Eugene Pasyuk, CLAS Collaboration

2012-04-01T23:59:59.000Z

66

Helium Compton Form Factor Measurements at CLAS  

SciTech Connect (OSTI)

The distribution of the parton content of nuclei, as encoded via the generalized parton distributions (GPDs), can be accessed via the deeply virtual Compton scattering (DVCS) process contributing to the cross section for leptoproduction of real photons. Similarly to the scattering of light by a material, DVCS provides information about the dynamics and the spatial structure of hadrons. The sensitivity of this process to the lepton beam polarization allows to single-out the DVCS amplitude in terms of Compton form factors that contain GPDs information. The beam spin asymmetry of the $^4$He($\\vec {\\mathrm e}$,e$' \\gamma ^4$He) process was measured in the experimental Hall B of the Jefferson Laboratory to extract the real and imaginary parts of the twist-2 Compton form factor of the $^4$He nucleus. The experimental results reported here demonstrate the relevance of this method for such a goal, and suggest the dominance of the Bethe-Heitler amplitude to the unpolarized process in the kinematic range explored by the experiment.

Voutier, Eric J.-M. [Laboratoire de Physique Subatomique et Cosmologie

2013-07-01T23:59:59.000Z

67

February 14, 2013 1 College: CLAS  

E-Print Network [OSTI]

and quarries on watershed health, management of their own companies, and instruction at all educational levels

Veerman, J. J. P.

68

UNIVERSITY OF CALIFORNIA- BERKELEY UCRL CLAS CO  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layeredof EnergyLeaseEnergyUNCLASSIFIED 2 1 2CALIFORNIA>

69

Deeply virtual Compton scattering and generalized parton distributions at CLAS  

SciTech Connect (OSTI)

The exclusive electroproduction of real photons and mesons at high momentum transfer allows us to access the Generalized Parton Distributions (GPDs). The formalism of the GPDs provides a unified description of the hadronic structure in terms of quark and gluonic degrees of freedom. In particular, the Deeply Virtual Compton Scattering (DVCS), ep e2p2 , is one of the key reactions to determine the GPDs experimentally, as it is the simplest process that can be described in terms of GPDs. A dedicated experiment to study DVCS has been carried out in Hall B at Jefferson Lab. Beam-spin asymmetries, resulting from the interference of the Bethe-Heitler process and DVCS have been extracted over the widest kinematic range ever accessed for this reaction ( 1.2 < Q 2 < 3.7 (GeV/c 2, 0.09 < - t < 1.3 (GeV/c 2, 0.13 < x B < 0.46 . In this paper, the results obtained experimentally are shown and compared to GPD parametrizations.

Niccolai, Silvia

2008-11-01T23:59:59.000Z

70

NEUTRON DETECTION EFFICIENCY OF THE CLAS12 DETECTOR  

E-Print Network [OSTI]

of the Jefferson Lab 12 GeV upgrade, to obtain a preliminary estimate of it's neutron detection efficiency (NDE). Knowledge of the NDE of a detector is important for calculating systematic uncertainty of neutron measurements, so knowledge of NDE is essential. An important experiment requiring knowledge of NDE is measuring

Gilfoyle, Jerry

71

En.lighten Country Lighting Assessments (CLAs) | Open Energy Information  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Office of InspectorConcentrating Solar Power Basics (The followingDirectLow CarbonOpen1Model |RuralKansas)

72

Study of Generalized Parton Distributions and Deeply Virtual Compton Scattering on the nucleon with the CLAS and CLAS12 detectors at the Jefferson Laboratory  

SciTech Connect (OSTI)

The exclusive leptoproduction of a real photon is considered to be the "cleanest" way to access the Generalized Parton Distribution (GPD). This process is called Deeply Virtual Compton Scattering (DVCS) lN {yields} lN{gamma} , and is sensitive to all the four GPDs. Measuring the DVCS cross section is one of the main goals of this thesis. In this thesis, we present the work performed to extract on a wide phase-space the DVCS cross-section from the JLab data at a beam energy of 6 GeV.

Baptiste Guegan

2012-11-01T23:59:59.000Z

73

Deeply virtual Compton scattering on longitudinally polarized protons and neutrons at CLAS  

E-Print Network [OSTI]

This paper focuses on a measurement of deeply virtual Compton scattering (DVCS) performed at Jefferson Lab using a nearly-6-GeV polarized electron beam, two longitudinally polarized (via DNP) solid targets of protons (NH3) and deuterons (ND3) and the CEBAF Large Acceptance Spectrometer. Here, preliminary results for target-spin asymmetries and double (beam-target) asymmetries for proton DVCS, as well as a very preliminary extraction of beam-spin asymmetry for neutron DVCS, are presented and linked to Generalized Parton Distributions.

Silvia Niccolai; for the CLAS Collaboration

2012-07-13T23:59:59.000Z

74

Deeply virtual Compton scattering on longitudinally polarized protons and neutrons at CLAS  

SciTech Connect (OSTI)

This paper focuses on a measurement of deeply virtual Compton scattering (DVCS) performed at Jefferson Lab using a nearly-6-GeV polarized electron beam, two longitudinally polarized (via DNP) solid targets of protons (NH{sub 3}) and deuterons (ND{sub 3}) and the CEBAF Large Acceptance Spectrometer. Here, preliminary results for target-spin asymmetries and double (beam-target) asymmetries for proton DVCS, as well as a very preliminary extraction of beam-spin asymmetry for neutron DVCS, are presented and linked to Generalized Parton Distributions.

Silvia Niccolai

2012-04-01T23:59:59.000Z

75

The Meson Spectroscopy Program Using the Forward Tagger with CLAS12 at Jefferson Lab  

SciTech Connect (OSTI)

The 12 GeV upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) will enable a new generation of experiments in hadronic nuclear physics at Jefferson Lab, seeking to address fundamental questions in QCD. For example, confirming the existence of exotic states, suggested by both quark models and lattice calculations, would allow gluonic degrees of freedom to be explored, and may help explain the role played by gluons in the QCD interaction. In Experimental Hall B, meson spectroscopy (the MesonEx experiment) will be performed using low Q2 electron scattering to produce quasi-real photons. The scattered electron is detected at small angles by the Forward Tagger device, determining the properties of the photon on an event-by-event basis. This technique has notable advantages over real photon beams, and over hadronic beam experiments, where most experimental data exists. This article will focus on the development of the Forward Tagger by the INFN Genova group, and the proposed MesonEx experiment.

Fegan, Stuart [INFN-GENOVA

2014-11-01T23:59:59.000Z

76

Spectroscopy of exotic baryons with CLAS: search for ground and first excited states  

SciTech Connect (OSTI)

In the last year many Collaborations reported about the evidence of a possible pentaquark state but so far the results are not yet conclusive. New dedicated experiments with higher statistics and precision are necessary to confirm the pentaquark existence and its properties. In this contribution, I will report about a new photoproduction experiment on a proton target, the so-called 'G11' experiment, just performed in the Hall-B at Jefferson Lab that collected ten times the existing statistics.

M. Battaglieri

2004-07-20T23:59:59.000Z

77

Measurement of the neutron F2 structure function via spectator tagging with CLAS  

SciTech Connect (OSTI)

We report on the first measurement of the F2 structure function of the neutron from semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ?< 100 MeV and their angles to ?> 100 degrees relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F2n data collected cover the nucleon resonance and deep-inelastic regions over a wide range of x for 0.65 < Q2 < 4.52 GeV2, with uncertainties from nuclear corrections estimated to be less than a few percent. These measurements provide the first determination of the neutron to proton structure function ratio F2n/F2p at 0.2 ?< x ?< 0.8, essentially free of nuclear corrections.

Baillie, N; Zhang, J; Bosted, P; Bultmann, S; Christy, M E; Fenker, H; Griffioen, K A; Keppel, C E; Kuhn, S E; Melnitchouk, W; Tvaskis, V; Adhikari, K P; Adikaram, D; Aghasyan, M; Amaryan, M J; Anghinolfini, M; Arrington, J; Avakian, H; Baghdasaryan, H; Battaglieri, M; Biselli, A A; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Crede, V; D& #x27; Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Dey, B; Djalali, C; Dodge, G; Domingo, J; Doughty, D; Dupre, R; Dutta, D; Ent, R; Egiyan, H; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Fradi, A; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Guegan, B; Guidal, M; Guler, N; Guo, L; Hafidi, K; Heddle, D; Hicks, K; Holtrop, M; Hungerford, E; Hyde, C E; Ilieva, Y; Ireland, D G; Ispiryan, M; Isupov, E L; Jawalkar, S S; Jo, H S; Kalantarians, N; Khandaker, M; Khetarpal, P; Kim, A; Kim, W; King, P M; Klein, A; Klein, F J; Klimenko, A; Kubarovsky, V; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, I.J. D; Mao, Y; Markov, N; McKinnon, B; Mineeva, T; Morrison, B; Moutarde, H; Munevar, E; Nadel-Turonski, P; Ni, A; Niccolai, S; Niculescu, I; Niculescu, G; Osipenko, M; Ostrovidov, A I; Pappalardo, L; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Pisano, S; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Sharabian, Y G; Sober, D I; Sokhan, D; Stepanyan, S; Stepanyan, S S; Stoler, P; Strauch, S; Taiuti, M; Tang, W; Ungaro, M; Vineyard, M F; Voutier, E; Watts, D P; Weinstein, L B; Weygand, D P; Wood, M H; Zana, L

2012-04-06T23:59:59.000Z

78

Measurement of the neutron F2 structure function via spectator tagging with CLAS  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We report on the first measurement of the F2 structure function of the neutron from semi-inclusive scattering of electrons from deuterium, with low-momentum protons detected in the backward hemisphere. Restricting the momentum of the spectator protons to ? 100 degrees relative to the momentum transfer allows an interpretation of the process in terms of scattering from nearly on-shell neutrons. The F2n data collected cover the nucleon resonance and deep-inelastic regions over a wide range of x for 0.65 2 2, with uncertainties from nuclear corrections estimated to be less than a few percent. These measurements provide the first determination of the neutron to proton structure function ratio F2n/F2p at 0.2 ?< x ?< 0.8, essentially free of nuclear corrections.

Baillie, N; Zhang, J; Bosted, P; Bultmann, S; Christy, M E; Fenker, H; Griffioen, K A; Keppel, C E; Kuhn, S E; Melnitchouk, W; Tvaskis, V; Adhikari, K P; Adikaram, D; Aghasyan, M; Amaryan, M J; Anghinolfini, M; Arrington, J; Avakian, H; Baghdasaryan, H; Battaglieri, M; Biselli, A A; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Crede, V; D' Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Dey, B; Djalali, C; Dodge, G; Domingo, J; Doughty, D; Dupre, R; Dutta, D; Ent, R; Egiyan, H; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Fegan, S; Fradi, A; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Guegan, B; Guidal, M; Guler, N; Guo, L; Hafidi, K; Heddle, D; Hicks, K; Holtrop, M; Hungerford, E; Hyde, C E; Ilieva, Y; Ireland, D G; Ispiryan, M; Isupov, E L; Jawalkar, S S; Jo, H S; Kalantarians, N; Khandaker, M; Khetarpal, P; Kim, A; Kim, W; King, P M; Klein, A; Klein, F J; Klimenko, A; Kubarovsky, V; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, I.J. D; Mao, Y; Markov, N; McKinnon, B; Mineeva, T; Morrison, B; Moutarde, H; Munevar, E; Nadel-Turonski, P; Ni, A; Niccolai, S; Niculescu, I; Niculescu, G; Osipenko, M; Ostrovidov, A I; Pappalardo, L; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Pisano, S; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Sharabian, Y G; Sober, D I; Sokhan, D; Stepanyan, S; Stepanyan, S S; Stoler, P; Strauch, S; Taiuti, M; Tang, W; Ungaro, M; Vineyard, M F; Voutier, E; Watts, D P; Weinstein, L B; Weygand, D P; Wood, M H; Zana, L

2012-04-06T23:59:59.000Z

79

CLAS Associate Director John Frechione suffering the adverse March weather in  

E-Print Network [OSTI]

, University of California, Irvine) at the Latin American Social and Public Policy Conference. (See page 3, Ecuador, Argentina, Brazil, and Poland and has presented man- agement seminars in Turkey, Slovakia

Machery, Edouard

80

Final Report for Bio-Inspired Approaches to Moving-Target Defense Strategies  

SciTech Connect (OSTI)

This report records the work and contributions of the NITRD-funded Bio-Inspired Approaches to Moving-Target Defense Strategies project performed by Pacific Northwest National Laboratory under the technical guidance of the National Security Agencys R6 division. The project has incorporated a number of bio-inspired cyber defensive technologies within an elastic framework provided by the Digital Ants. This project has created the first scalable, real-world prototype of the Digital Ants Framework (DAF)[11] and integrated five technologies into this flexible, decentralized framework: (1) Ant-Based Cyber Defense (ABCD), (2) Behavioral Indicators, (3) Bioinformatic Clas- sification, (4) Moving-Target Reconfiguration, and (5) Ambient Collaboration. The DAF can be used operationally to decentralize many such data intensive applications that normally rely on collection of large amounts of data in a central repository. In this work, we have shown how these component applications may be decentralized and may perform analysis at the edge. Operationally, this will enable analytics to scale far beyond current limitations while not suffering from the bandwidth or computational limitations of centralized analysis. This effort has advanced the R6 Cyber Security research program to secure digital infrastructures by developing a dynamic means to adaptively defend complex cyber systems. We hope that this work will benefit both our clients efforts in system behavior modeling and cyber security to the overall benefit of the nation.

Fink, Glenn A.; Oehmen, Christopher S.

2012-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

E-Print Network 3.0 - anaerobic upflow column Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

were hermetically sealed. Only the filter was heated... , pyrolysis, and biological gaSification by anaerobic digestion have been in vestigated. Due to the very... heterogeneous...

82

E-Print Network 3.0 - anaerobic sewage sludge Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Process, " Symposium on Clean Fuels From Biomas... , pyrolysis, and biological gaSification by anaerobic digestion ... Source: Columbia University - Waste-to-Energy Research...

83

J. Phys. 1Fianc.e 4 j1994) 1627-1639 NOVEMBER 1994, PAGE 1627 Clas~ification  

E-Print Network [OSTI]

, or the identity record of a persan into a name and a photograph. Then incomplete information on either the name

Paris-Sud XI, Université de

84

Measurements of $ep \\to e^\\prime ?^+n$ at W = 1.6 - 2.0 GeV and extraction of nucleon resonance electrocouplings at CLAS  

E-Print Network [OSTI]

Differential cross sections of the exclusive process $e p \\to e^\\prime \\pi^+ n$ were measured with good precision in the range of the photon virtuality $Q^2 = 1.8 - 4.5$ GeV$^2$, and the invariant mass range of the $\\pi^+ n$ final state W = 1.6 - 2.0 GeV using the CEBAF Large Acceptance Spectrometer. Data were collected with nearly complete coverage in the azimuthal and polar angles of the $n\\pi^+$ center-of-mass system. More than 37,000 cross section points were measured. The contributions of the isospin $I = {1\\over 2}$ resonances $N(1675){5\\over 2}^-$, $N(1680){5\\over 2}^+$ and $N(1710){1\\over 2}^+$ were extracted at different values of $Q^2$ using a single-channel, energy-dependent resonance amplitude analysis. Two different approaches, the unitary isobar model and the fixed-$t$ dispersion relations, were employed in the analysis. We observe significant strength of the $N(1675){5\\over 2}^-$ in the $A_{1/2}$ amplitude, which is in strong disagreement with quark models that predict both transverse amplitudes to be strongly suppressed. For the $N(1680){5\\over 2}^+$ we observe a slow changeover from the dominance of the $A_{3/2}$ amplitude at the real photon point ($Q^2=0$) to a $Q^2$ where $A_{1/2}$ begins to dominate. The scalar amplitude $S_{1/2}$ drops rapidly with $Q^2$ consistent with quark model prediction. For the $N(1710){1\\over 2}^+$ resonance our analysis shows significant strength for the $A_{1/2}$ amplitude at $Q^2 < 2.5$ GeV$^2$.

K. Park; I. G. Aznauryan; V. D. Burkert; the CLAS collaboration

2014-12-17T23:59:59.000Z

85

Measurement of the nearly free neutron structure function using spectator tagging in inelastic 2H(e,e'p s)X scattering with CLAS  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Much less is known about neutron structure than that of the proton due to the absence of free neutron targets. Neutron information is usually extracted from data on nuclear targets such as deuterium, requiring corrections for nuclear binding and nucleon off-shell effects. These corrections are model dependent and have significant uncertainties, especially for large values of the Bjorken scaling variable x. As a consequence, the same data can lead to different conclusions, for example, about the behavior of the d quark distribution in the proton at large x.

Tkachenko, Svyatoslav; Baillie, Nathan; Kuhn, Sebastian; Zhang, J; Arrington, John; Bosted, Peter; Bueltmann, Stephen; Christy, Michael; Fenker, Howard; Griffioen, Keith; Kalantarians, Narbe; Keppel, Cynthia; Melnitchouk, Wolodymyr; Tvaskis, Vladas; Adhikari, Krishna; Aghasyan, Mher; Amaryan, Moskov; Anefalos Pereira, Sergio; Avagyan, Harutyun; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bedlinskiy, Ivan; Biselli, Angela; Briscoe, William; Brooks, William; Burkert, Volker; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Charles, Gabriel; Cole, Philip; Contalbrigo, Marco; Cortes, Olga; Crede, Volker; D'Angelo, Annalisa; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dupre, Raphael; Egiyan, Hovanes; El Alaoui, Ahmed; El Fassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Fleming, Jamie; Garillon, Brice; Gevorgyan, Nerses; Ghandilyan, Yeranuhi; Gilfoyle, Gerard; Giovanetti, Kevin; Girod-Gard, Francois-Xavier; Goetz, John; Golovach, Evgeny; Gothe, Ralf; Guidal, Michel; Guo, Lei; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Harrison, Nathan; Hattawy, Mohammad; Hicks, Kenneth; Ho, Dao; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Jo, Hyon-Suk; Keller, Dustin; Khandaker, Mahbubul; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Koirala, Suman; Kubarovsky, Valery; Kuleshov, Sergey; Lenisa, Paolo; Lewis, Stefanie; Livingston, Kenneth; Lu, H; MacCormick, Marion; MacGregor, Ian; Markov, Nikolai; Mayer, Michael; McKinnon, Bryan; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Montgomery, Rachel; MOUTARDE, Herve; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria; Osipenko, Mikhail; Pappalardo, Luciano; Paremuzyan, Rafayel; Park, Kijun; Pasyuk, Eugene; Phillips, J J; Pisano, Silvia; Pogorelko, Oleg; Pozdniakov, Serguei; Price, J W; Procureur, Sebastien; Protopopescu, Dan; Puckett, Andrew; Rimal, Dipak; Ripani, Marco; Rizzo, Alessandro; Rosner, Guenther; Rossi, Patrizia; Roy, Priyashree; Sabatie, Franck; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Senderovich, Igor; Sharabian, Youri; Simonyan, Ani; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Stepan; Stepanyan, Samuel; Strauch, Steffen; Tang, Wei; Ungaro, Maurizio; Vlasov, Alexander; Voskanyan, Hakob; VOUTIER, Eric; Walford, Natalie; Watts, Daniel; Wei, Xiangdong; Weinstein, Lawrence; Wood, Michael; Zana, Lorenzo; Zonta, Irene

2014-04-01T23:59:59.000Z

86

Measurement of the nearly free neutron structure function using spectator tagging in inelastic 2H(e,e'p s)X scattering with CLAS  

SciTech Connect (OSTI)

Much less is known about neutron structure than that of the proton due to the absence of free neutron targets. Neutron information is usually extracted from data on nuclear targets such as deuterium, requiring corrections for nuclear binding and nucleon off-shell effects. These corrections are model dependent and have significant uncertainties, especially for large values of the Bjorken scaling variable x. As a consequence, the same data can lead to different conclusions, for example, about the behavior of the d quark distribution in the proton at large x.

Tkachenko, Svyatoslav; Baillie, Nathan; Kuhn, Sebastian; Zhang, J; Arrington, John; Bosted, Peter; Bueltmann, Stephen; Christy, Michael; Fenker, Howard; Griffioen, Keith; Kalantarians, Narbe; Keppel, Cynthia; Melnitchouk, Wolodymyr; Tvaskis, Vladas; Adhikari, Krishna; Aghasyan, Mher; Amaryan, Moskov; Anefalos Pereira, Sergio; Avagyan, Harutyun; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bedlinskiy, Ivan; Biselli, Angela; Briscoe, William; Brooks, William; Burkert, Volker; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Charles, Gabriel; Cole, Philip; Contalbrigo, Marco; Cortes, Olga; Crede, Volker; D'Angelo, Annalisa; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dupre, Raphael; Egiyan, Hovanes; El Alaoui, Ahmed; El Fassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Fleming, Jamie; Garillon, Brice; Gevorgyan, Nerses; Ghandilyan, Yeranuhi; Gilfoyle, Gerard; Giovanetti, Kevin; Girod-Gard, Francois-Xavier; Goetz, John; Golovach, Evgeny; Gothe, Ralf; Guidal, Michel; Guo, Lei; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Harrison, Nathan; Hattawy, Mohammad; Hicks, Kenneth; Ho, Dao; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Jo, Hyon-Suk; Keller, Dustin; Khandaker, Mahbubul; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Koirala, Suman; Kubarovsky, Valery; Kuleshov, Sergey; Lenisa, Paolo; Lewis, Stefanie; Livingston, Kenneth; Lu, H; MacCormick, Marion; MacGregor, Ian; Markov, Nikolai; Mayer, Michael; McKinnon, Bryan; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Montgomery, Rachel; MOUTARDE, Herve; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria; Osipenko, Mikhail; Pappalardo, Luciano; Paremuzyan, Rafayel; Park, Kijun; Pasyuk, Eugene; Phillips, J J; Pisano, Silvia; Pogorelko, Oleg; Pozdniakov, Serguei; Price, J W; Procureur, Sebastien; Protopopescu, Dan; Puckett, Andrew; Rimal, Dipak; Ripani, Marco; Rizzo, Alessandro; Rosner, Guenther; Rossi, Patrizia; Roy, Priyashree; Sabatie, Franck; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Senderovich, Igor; Sharabian, Youri; Simonyan, Ani; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Stepan; Stepanyan, Samuel; Strauch, Steffen; Tang, Wei; Ungaro, Maurizio; Vlasov, Alexander; Voskanyan, Hakob; VOUTIER, Eric; Walford, Natalie; Watts, Daniel; Wei, Xiangdong; Weinstein, Lawrence; Wood, Michael; Zana, Lorenzo; Zonta, Irene

2014-04-01T23:59:59.000Z

87

Free Extreme Values Gerard Ben Arous and Dan Virgil Voiculescu  

E-Print Network [OSTI]

Free Extreme Values Gerard Ben Arous and Dan Virgil Voiculescu New York University and University at Berkeley Berkeley, CA 94720-3840 E-mail:dvv@math.berkeley.edu Abstract: Free probability analogues- sification of freely max-stable laws and their domains of attraction, using "free extremal convolutions

Ben Arous, Gérard

88

doi:10.1152/ajpheart.00806.2008 296:796-805, 2009. First published Jan 9, 2009;Am J Physiol Heart Circ Physiol  

E-Print Network [OSTI]

- sification; noninvasive monitoring THE MECHANICAL FUNCTION OF the cardiovascular system is gov- erned.physiology.orgDownloadedfrom #12;Respiratory modulation of heart sound morphology Guy Amit,1 Khuloud Shukha,2 Noam Gavriely,2 form 7 January 2009 Amit G, Shukha K, Gavriely N, Intrator N. Respiratory modulation of heart sound

Intrator, Nathan

89

REVIEW OF PARTICLE PHYSICS  

E-Print Network [OSTI]

by CLAS and PrimEx at CEBAF, and by PANDA at GSI. Recently,Switzerland Bologna, Italy CEBAF CENG CERN CFPA Trombay,

Beringer, Juerg

2013-01-01T23:59:59.000Z

90

Protons hog the momentum in neutron-rich nuclei | Argonne National...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

a greater fraction of the protons than neutrons to have high momentum in relatively neutron-rich nuclei. The CLAS detector completely surrounds an experimental target and is...

91

Update on adolescent immunization: pertussis, meningococcus, HPV, and the future.  

E-Print Network [OSTI]

is a frequent cause of prolonged cough illness in adults andcold to clas- by almost 99% ? PERTUSSIS (WHOOPING COUGH) sicwhooping cough, depending on the degree of preexisting

Yeh, S. H; Lieberman, J. M

2007-01-01T23:59:59.000Z

92

Studies of semi-inclusive and hard exclusive processes at Jlab  

SciTech Connect (OSTI)

The main goal of experiments proposed for the {\\tt CLAS12} detector in conjunction with the 12-GeV CEBAF accelerator is the study of the nucleon through hard exclusive, semi-inclusive, and inclusive processes. This will provide new insights into nucleon dynamics at the elementary quark and gluon level. In this contribution we provide an overview of ongoing studies of the structure of nucleon in terms of quark and gluon degrees of freedom and future physics program planned with CLAS and {\\tt CLAS12}.

Harutyun Avagyan

2008-06-19T23:59:59.000Z

93

Nutrition & Food Science, 3009 Science Hall, Wayne State University, Detroit, MI 48202Telephone: (313) 577-2500 Fax: (313) 577-8616 Email: ab8207@wayne.edu World Wide Web: www.clas.wayne.edu/nfs (revised brochure Sep 2012)  

E-Print Network [OSTI]

.A.) are offered. The MA degree can have an emphasis in Food Service Management or be done in conjunction to be in non-laboratory aspects of nutrition or food service. Required Component of Courses: (13 credit hours & Food Science, 3009 Science Hall, Wayne State University, Detroit, MI 48202Telephone: (313) 577-2500 Fax

Berdichevsky, Victor

94

Flutter-mills: from destructive phenomenon to the story of success  

E-Print Network [OSTI]

energy of wind, such a power plant hasn't been built yet. A clas, hydro power plants are important producers of electrical power and solar power plants are getting more

?umer, Slobodan

95

Jefferson Lab Weekly Briefs March 25, 2015 | Jefferson Lab  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

was planned for the months of March and April. Physics Jefferson Lab Published Journal Articles March 16-20 S. Pisano et al. (CLAS Collaboration). "Single and double spin...

96

TEMPLATE DESIGN 2008 www.PosterPresentations.com  

E-Print Network [OSTI]

position and energy of charged particles and the hit position of neutral particles. To model CLAS12's that will double the beam energy to 12 GeV and upgrade the detector in Hall B, CLAS12. See Figure 1. We are running and a new table was created in the MYSQL database. ec_build_strips.pl ­ This perl script was adapted from ec_build

Gilfoyle, Jerry

97

CORRESPONDENCE CURRENT SCIENCE, VOL. 106, NO. 5, 10 MARCH 2014 651  

E-Print Network [OSTI]

. Most of us are exposed to diesel exhaust (motor vehicle exhausts, other engines, power generators diesel exhaust ­ a potential human carcinogen The International Agency for Research on Cancer (IARC), which is a part of the World Health Organization (WHO), clas- sified diesel engine exhaust as carcino

Joshi, Yogesh Moreshwar

98

Precise measurement of the neutron magnetic form factor GMn [G superscript n subscript M] in the Few-GeV2 [V superscript 2] region  

E-Print Network [OSTI]

The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q2=1.04.8 [Q superscript 2 = 1.0-4.8] ??GeV2 [Ge V superscript 2] with the CLAS detector at Jefferson ...

Rowntree, D.

99

APPLICATION OF THE FUZZY MIN-MAX NEURAL NETWORK CLASSIFIER  

E-Print Network [OSTI]

. The fuzzy min-max classi cation network constitutes a promisimg pattern recognition approach that is based. Experimental results us- ing the modi ed model on a di cult pattern recognition prob- lem establishes of the fuzzy min-max clas- si cation neural network on a pattern recognition problem that involves both

Blekas, Konstantinos

100

A STUDENT NEWSLETTER SPRING 2007VISIONS of Latin America  

E-Print Network [OSTI]

Infrastructure in South America: economic Development vs. Environment integration? 8 Un lustro sin Roberto Bolaño elections in Paraguay in which president and former bishop Fernando Lugo ended 61 years of rule of traditional oral vs. written forms of communication in Andean education. CLAS welcomes submissions for Visions

Machery, Edouard

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Functional Data Analysis With Multi Layer Perceptrons  

E-Print Network [OSTI]

Analysis. We introduce a computation model for functional input data and we show that this model is a wellFunctional Data Analysis With Multi Layer Perceptrons Fabrice Rossi , Brieuc Conan-Guez and Fran as clas- sical multivariate data, because they are in general de- scribed by a finite set of input

Fleuret, François

102

Functional Data Analysis With Multi Layer Perceptrons0  

E-Print Network [OSTI]

Analysis. We introduce a computation model for functional input data and we show that this model is a wellFunctional Data Analysis With Multi Layer Perceptrons0 Fabrice Rossi1 , Brieuc Conan-Guez and Fran as clas- sical multivariate data, because they are in general de- scribed by a finite set of input

Rossi, Fabrice

103

Bag-of-Visual-Words Models for Adult Image Classification and Filtering Thomas Deselaers1  

E-Print Network [OSTI]

types of images are allowed. In the literature, different porn image filtering tech- niques were features for porn image classification are pre- sented and used in a retrieval/nearest neighbour clas model to discriminate between different classes of content-type. 2 Porn Image Identification For porn

Deselaers, Thomas

104

Composition (6 hours) ENG 11011 College Writing I * 3  

E-Print Network [OSTI]

with Pre-calculus I * 3 12012 Calculus with Pre-calculus II * 3 14001 Basic Mathematical Concepts I 4 14002 in Arts & Sciences CLAS G 21404 The Greek Achievement * 3 G 21405 The Roman Achievement * 3 ENG 21054 for courses listed below. ANTH 18630 Human Evolution * 3 L 18631 Issues in Human Evolution * Pre

Khan, Javed I.

105

Baryon Resonances in the Double Pion Channel at Jefferson Lab (CEBAF): Experimental and Physical Analysis Status and Perspectives  

E-Print Network [OSTI]

Decay of light quark excited baryons in the double pion channel is discussed, as a particular way of investigating poorly know baryon resonances and searching for "missing states" predicted by quark models. A possible approach to the data analysis is discussed and some preliminary data from the CLAS collaboration at Jefferson Laboratory are presented.

Marco Ripani

1999-02-18T23:59:59.000Z

106

Navigation in Structured Multimedia Documents using Presentation Context  

E-Print Network [OSTI]

Navigation in Structured Multimedia Documents using Presentation Context Loay SabryIsmail --- C in multimedia documents differs from the navigation in clas sical documents the fact that temporal information instants in the presentation of multimedia documents, and we describe how they can be used to navigate

Joseph Fourier Grenoble-I, Universit

107

Theory of masking with codewords in hardware: low-weight dth-order correlation-immune Boolean  

E-Print Network [OSTI]

, d = 4) and (n = 10, d {4, 5}). These results set new bounds for the minimal number of lines difficulty when design- ing a masking scheme is to pass through the substitution boxes (sboxes). Clas- sical with the entropy. In this article, we are interested in a masking solution with- out timing overhead and a limited

108

Iron isotopes constrain biologic and abiologic processes in banded iron formation genesis  

E-Print Network [OSTI]

diagenetic processes that produced a range of d56 Fe values: (1) addition of mar- ine hydrothermal Fe2þ aq column, delivery of organic carbon produced by photosynthesis, and low clas- tic input. We infer that DIR, marine hydrothermal) were Fe2+ . Contrary to common be- lief, however, hematite or goethite

Roden, Eric E.

109

Toward a Common Method ofToward a Common Method of Cost Estimation forCost Estimation for  

E-Print Network [OSTI]

The Context for this TalkThe Context for this Talk At last year's workshop I reviewed/discussed the: · Common (IEAGHG) · Clas Ekström (Vattenfall) · Mike Matuszewski (USDOE) · Sean McCoy (IEA) · Ed Rubin (CMU) (Chair

110

The EMC Effect in Spin Structure Functions A 12 GeV letter of intent to Jefferson Lab PAC 35  

E-Print Network [OSTI]

The EMC Effect in Spin Structure Functions A 12 GeV letter of intent to Jefferson Lab PAC 35-dependent EMC effect uti- lizing CLAS12 in Hall B. We will polarize 7 Li, in which a highly polarized proton|7Li 1 in a range of 2 EMC effect emphasizes

Gilfoyle, Jerry

111

A Taxonomy of Wireless Micro-Sensor Network Models Sameer Tilak Nael B. Abu-Ghazaleh Wendi Heinzelman  

E-Print Network [OSTI]

A Taxonomy of Wireless Micro-Sensor Network Models £ Sameer Tilak Nael B. Abu-Ghazaleh Wendi wireless networks. This paper examines this emerging field to clas- sify wireless micro-sensor networks to classify wireless micro-sensor networks. In partic- ular, we classify the aspects of wireless micro

Han, Richard Y.

112

EFC Meeting Agenda Thursday, September 5, 1:00-2:00 PM  

E-Print Network [OSTI]

, 2013 2. Announcements 3. Update on EFC election 4. Standing Committees: a. Updates on standingE General Education Courses (GECs): adopt languages for our GEC requirement that match CLAS's categories for underrepresented minorities. e. Graduate education and TA support. 6. New Business #12;

Casavant, Tom

113

Sensors and Actuators A 171 (2011) 260265 Contents lists available at ScienceDirect  

E-Print Network [OSTI]

the Equivalent Circuit Method (ECM) [4], while Castillo [5] built a one- dimensional KLM model that takes considering the vibrator with flexural mode. Identical exper- imental conditions were used in the simulation to a high-intensity acoustic vibrator. The actuator for noncontact levitation consists of one clas- sical

Cao, Wenwu

114

Simultaneous Greedy Analysis Pursuit for Compressive Sensing of Multi-Channel ECG Signals  

E-Print Network [OSTI]

Simultaneous Greedy Analysis Pursuit for Compressive Sensing of Multi-Channel ECG Signals Yurrit sensing for multi- channel ECG signals. In contrast to the traditional sparse approach where the signal of compressive sensing for ECG signals. Moreover, to efficiently recover multi-channel ECG signals, clas- sical

115

Branching Ratio of the Electromagnetic Decay of the ?+(1385)  

SciTech Connect (OSTI)

The CLAS detector was used to obtain the first ever measurement of the electromagnetic decay of the ?*+(1385) from the reaction ?p ? K0 ?*+(1385). A real photon beam with a maximum energy of 3.8 GeV was incident on a liquid-hydrogen target, resulting in the photoproduction of the kaon and ?* hyperon. Kinematic fitting was used to separate the reaction channel from the background processes. The fitting algorithm exploited a new method to kinematically fit neutrons in the CLAS detector, leading to the partial width measurement of 250.0 56.9(stat)-41.2+34.3(sys) keV. A U-spin symmetry test using the SU(3) flavor-multiplet representation yields predictions for the ?*+(1385) ? ?+? and ?*0(1385) ? ?? partial widths that agree with the experimental measurements.

Keller, D; Adhikari, K P; Adikaram, D; Amaryan, M J; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Bedlinskiy, I; Biselli, A S; Bookwalter, C; Boiarinov, S; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Cole, P L; Contalbrigo, M; Crede, V; D& #x27; Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Djalali, C; Doughty, D; Dupre, R; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Griffioen, K A; Guidal, M; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jo, H S; Joo, K; Khandaker, M; Khertarpal, P; Kim, A; Kim, W; Klein, F J; Kubarovsky, A; Kubarovsky, V; Kuleshov, S V; Lu, H Y; MacGregor, I.J. D; Mao, Y; Markov, N; Mayer, M; McKinnon, B; Meyer, C A; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Anefalos Pereira, S; Pisano, S; Pogorelko, O; Pozdniakov, S; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Stoler, P; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tkachenko, S; Vernarsky, B; Vineyard, M F; Vlassov, A V; Voskanyan, H; Voutier, E; Wood, M H; Zachariou, N; Zana, L; Zhao, B

2012-03-23T23:59:59.000Z

116

Progress on Neutron-Target Multipoles above 1 GeV  

SciTech Connect (OSTI)

We report a new extraction of nucleon resonance couplings using ?{sup ?} photo-production cross sections on the neutron. The world database for the process ?n ? ?{sup ?}p above 1 GeV has quadrupled with the addition of new differential cross sections from the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab in Hall B. Differential cross sections from CLAS have been improved with a new final-state interaction determination using a diagrammatic technique taking into account the SAID phenomenological NN and ?N final-state interaction amplitudes. Resonance couplings have been extracted and compared to previous determinations. With the addition of these new cross sections, significant changes are seen in the high-energy behavior of the SAID cross sections and amplitudes.

Strakovsky, I I; Gao, H; Briscoe, W J; Dutta, D; Kudryavtsev, A E; Mirazite, M; Paris, M; Rossi, P; Stepanyan, S; Tarasov, V E

2012-12-01T23:59:59.000Z

117

Branching Ratio of the Electromagnetic Decay of the ?+(1385)  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The CLAS detector was used to obtain the first ever measurement of the electromagnetic decay of the ?*+(1385) from the reaction ?p ? K0 ?*+(1385). A real photon beam with a maximum energy of 3.8 GeV was incident on a liquid-hydrogen target, resulting in the photoproduction of the kaon and ?* hyperon. Kinematic fitting was used to separate the reaction channel from the background processes. The fitting algorithm exploited a new method to kinematically fit neutrons in the CLAS detector, leading to the partial width measurement of 250.0 56.9(stat)-41.2+34.3(sys) keV. A U-spin symmetry test using the SU(3) flavor-multiplet representation yields predictions for the ?*+(1385) ? ?+? and ?*0(1385) ? ?? partial widths that agree with the experimental measurements.

Keller, D; Adhikari, K P; Adikaram, D; Amaryan, M J; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Bedlinskiy, I; Biselli, A S; Bookwalter, C; Boiarinov, S; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Cole, P L; Contalbrigo, M; Crede, V; D' Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Djalali, C; Doughty, D; Dupre, R; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Griffioen, K A; Guidal, M; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jo, H S; Joo, K; Khandaker, M; Khertarpal, P; Kim, A; Kim, W; Klein, F J; Kubarovsky, A; Kubarovsky, V; Kuleshov, S V; Lu, H Y; MacGregor, I.J. D; Mao, Y; Markov, N; Mayer, M; McKinnon, B; Meyer, C A; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Anefalos Pereira, S; Pisano, S; Pogorelko, O; Pozdniakov, S; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Stoler, P; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tkachenko, S; Vernarsky, B; Vineyard, M F; Vlassov, A V; Voskanyan, H; Voutier, E; Wood, M H; Zachariou, N; Zana, L; Zhao, B

2012-03-23T23:59:59.000Z

118

Measurements of spin observables in pseudo-scalar meson photo-production using polarized neutrons in solid HD  

SciTech Connect (OSTI)

A measurement of psuedo-scalar meson photo production from longitudinally polarized solid HD has been carried out with the CLAS at Thomas Jefferson National Accelerator Facility (Jlab) with circularly and linearly polarized photon beams. Its aim is to measure a complete set of spin observables for the neutron simultaneously from the same experiment. As a polarized neutron, deutron in HD was used. Preliminary asymmetries are shown for the {pi}{sup -} channel.

Kageya, Tsuneo [JLAB, Newport News, VA (United States)

2014-01-01T23:59:59.000Z

119

Polarization observables from the photoproduction of omega-mesons using linearly polarized photons  

SciTech Connect (OSTI)

We report on the photon beam asymmetry, {Sigma}, of the {omega} meson decaying into {pi}{sup +}, {pi}{sup -}, {pi}{sup 0} using a beam of linearly polarized photons in the photon energy region of E{sub {gamma}} = 1.9 GeV. These preliminary results are from the summer 2005 g8b dataset, which were collected with the CLAS detector in Hall B of Jefferson Lab.

D. Martinez, P.L. Cole, CLAS Collaboration

2012-04-01T23:59:59.000Z

120

Polarization Observables From The Photoproduction Of Omega-Mesons Using Linearly Polarized Photons  

SciTech Connect (OSTI)

We report on the extraction of Polarization Observables Spin Density Matrix Elements (SDMEs), and Beam Asymmetry Sigma for omega meson photoproduction using a beam of linearly polarized photons in the photon energy region of Egamma = 1.3 to 1.7 GeV, by means of the angular distributions of the daughter pions from omega decay. These preliminary results are from the g8b dataset, which were collected with the CLAS detector in Hall B of Jefferson Lab.

Martinez, Danny [Idaho State University, Pocatello, ID (United States); Cole, Philip L. [Idaho State University, Pocatello, ID (United States)

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Preliminary results of t and f asymmetries for {eta} photoproduction from the proton  

SciTech Connect (OSTI)

We present preliminary data for the T and F asymmetries in {eta} photoproduction from the proton, along with comparisons to theoretical predictions. The data used in the present analysis were taken using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab, a cryogenic target which utilized transversely polarized protons in a butanol target, and incident tagged photons with energy between 0.62 and 2.93 GeV.

Tucker, Ross J. [Arizona State Univ., Tempe, AZ (United States); Ritchie, Barry G. [Arizona State Univ., Tempe, AZ (United States); Dugger, Michael R. [Arizona State Univ., Tempe, AZ (United States)

2014-01-01T23:59:59.000Z

122

Polarization Measurements in Photoproduction with CEBAF Large Acceptance Spectrometer  

SciTech Connect (OSTI)

A significant part of the experimental program in Hall-B of the Jefferson Lab is dedicated to the studies of the structure of baryons. CEBAF Large Acceptance Spectrometer (CLAS), availability of circularly and linearly polarized photon beams and recent addition of polarized targets provides remarkable opportunity for single, double and in some cases triple polarization measurements in photoproduction. An overview of the experiments will be presented.

E. Pasyuk

2010-05-01T23:59:59.000Z

123

Diversity Outlook, November 2012  

E-Print Network [OSTI]

decades. I extend my sincere thanks to Sr. Vice Provost Sara Rosen and CLAS Dean Danny Anderson for their support and guidance in making this recognition possible. Full details are on page 2; I hope the entire campus community will attend to show our.... The committee responsible for the video: Frank Barthell, producer, and Corey Stone, Office of Public Affairs; Allen Humphrey, assistant director, Human Resources; Patti Wakolee, senior academic advisor; Nicole Hodges Persley, theatre faculty; Mary Ellen...

2012-11-01T23:59:59.000Z

124

Measurements Of Spin Observables In Pseudoscalar-Meson Photo-Production Using Polarized Neutrons In Solid HD  

SciTech Connect (OSTI)

Psuedo-scalar meson photo production measurements have been carried out with longitudinally-polarized neutrons using the circularly and linearly polarized photon beams and the CLAS at Thomas Jefferson National Accelerator Facility (Jlab). The experiment aims to obtain a complete set of spin observables on an efficient neutron target. Preliminary E asymmetries for the exclusive reaction, gamma + n(p)--> pi- + p(p), selecting quasi free neutron kinematics are discussed.

Kageya, Tsuneo

2014-01-01T23:59:59.000Z

125

Nucleon Structure Studies with Electromagnetic Probes  

SciTech Connect (OSTI)

Summarized in this report is the progress achieved during the period from March 1, 2008 to June 14, 2009 under contract number DE-FG02-03ER41252. This is the final technical report under this contract. The experimental work described here is part of the electromagnetic nuclear physics program of the CEBAF Large Acceptance Spectrometer (CLAS) Collaboration at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) that published 17 journal articles during the period of this report. One of these journal articles reported on the results of precise measurements of the neutron magnetic form factor. I was a spokesperson on this experiment and the publication of these results is the culmination of years of effort by a small subset of the CLAS Collaboration. As usual, undergraduate students were involved in all aspects of this work. Three Union College students participated in this program during the window of this report and one presented a paper on his work at the 2009 National Conference on Undergraduate Research (NCUR22). In this report, I discuss recent progress on the measurements of the neutron magnetic form factor and describe my service work for the CLAS Collaboration.

Vineyard, Michael F.

2011-03-31T23:59:59.000Z

126

Beam Spin Asymmetry Measurements from Deeply Virtual Meson Production  

SciTech Connect (OSTI)

Study of deeply virtual exclusive meson production (DVMP), is being conducted in the E1-DVCS experiment with the CLAS detector at Jefferson Lab. The main motivation of the experiment is to characterize the partonic properties of the nucleon in the framework of generalized parton distributions (GPDs). The data were taken in the spring of 2005 using a 5.7 GeV longitudinally polarized electron beam and an unpolarized hydrogen target. We report on the on-going beam spin asymmetry analysis for pseudo-scalar channels and future experiments.

K. Joo; R. De Masi; M. Garcon; V. Kubarovsky; P. Stoler; M. Ungaro; B. Zhao

2007-06-01T23:59:59.000Z

127

Strangeness Suppression of qq? Creation Observed in Exclusive Reactions  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ?K+, p?0, and n?+, with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization, we extract qq creation probabilities for the first time in exclusive two-body production, in which only a single qq pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to nonstrange pairs, similar to that seen in high-energy production.

Mestayer, Mac [JLAB; Park, Kijun; Adhikari, Krishna; Aghasyan, Mher; Anefalos Pereira, Sergio; Ball, Jacques; Battaglieri, Marco; Batourine, V; Bedlinskiy, Ivan; Biselli, Angela; Boyarinov, Sergey; Briscoe, William; Brooks, William; Burkert, Volker; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Charles, Gabriel; Colaneri, Luca; Cole, Philip; Contalbrigo, Marco; Cortes, Olga; Crede, Volker; D'Angelo, Annalisa; Dashyan, Natalya; De Vita, Raffaella; Deur, Alexandre; Djalali, Chaden; Doughty, David; Dupre, Raphael; El Alaoui, Ahmed; El Fassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Fleming, Jamie; Forest, Tony; Garillon, Brice; Garcon, Michel; Ghandilyan, Yeranuhi; Gilfoyle, Gerard; Giovanetti, Kevin; Girod-Gard, Francois-Xavier; Goetz, John; Golovach, Evgeny; Gothe, Ralf; Griffioen, Keith; Guegan, Baptiste; Guidal, Michel; Hakobyan, Hayk; Hanretty, Charles; Hattawy, Mohammad; Holtrop, Maurik; Hughes, Simon; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Jiang, Hao; Jo, Hyon-Suk; Joo, Kyungseon; Keller, Dustin; Khandaker, Mahbubul; Kim, Andrey; Kim, Wooyoung; Koirala, Suman; Kubarovsky, Valery; Kuleshov, Sergey; Lenisa, Paolo; Levine, William; Livingston, Ken; Lu, Haiyun; MacGregor, Ian; Mayer, Michael; McKinnon, Bryan; Meyer, Curtis; Mirazita, Marco; Mokeev, Viktor; Montgomery, Rachel; Moody, Cristina; Moutarde, Herve; Movsisyan, Aram; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria; Osipenko, Mikhail; Ostrovidov, Alexander; Pappalardo, Luciano; Paremuzyan, Rafayel; Peng, Peng; Phelps, William; Pisano, Silvia; Pogorelko, Oleg; Pozdniakov, Serguei; Price, John; Protopopescu, Dan; Puckett, Andrew; Raue, Brian; Rimal, Dipak; Ripani, Marco; Rizzo, Alessandro; Rosner, Guenther; Roy, Priyashree; Sabatie, Franck; Saini, Mukesh; Schott, Diane; Schumacher, Reinhard; Simonyan, Ani; Sokhan, Daria; Strauch, Steffen; Sytnik, Valeriy; Tang, Wei; Tian, Ye; Ungaro, Maurizio; Vernarsky, Brian; Vlasov, Alexander; Voskanyan, Hakob; Voutier, Eric; Walford, Natalie; Watts, Daniel; Wei, Xiangdong; Weinstein, Lawrence; Wood, Michael; Zachariou, Nicholas; Zhang, Jixie; Zhao, Zhiwen; Zonta, Irene

2014-10-01T23:59:59.000Z

128

{eta}{sup '} Photoproduction on the Proton for Photon Energies from 1.527 to 2.227 GeV  

SciTech Connect (OSTI)

Differential cross sections for the reaction {gamma}p{yields}{eta}{sup '}p have been measured with the CLAS spectrometer and a tagged photon beam with energies from 1.527 to 2.227 GeV. The results reported here possess much greater accuracy than previous measurements. Analyses of these data suggest for the first time the coupling of the {eta}{sup '}N channel to both the S{sub 11}(1535) and P{sub 11}(1710) resonances, known to couple strongly to the {eta}N channel in photoproduction on the proton, and the importance of J=3/2 resonances in the process.

Dugger, M.; Ball, J.P.; Collins, P.; Pasyuk, E.; Ritchie, B.G. [Arizona State University, Tempe, Arizona 85287-1504 (United States); Adams, G.; Cummings, J.P.; Empl, A.; Hu, J.; Klusman, M.; Kubarovsky, V.; Napolitano, J.; Stoler, P. [Rensselaer Polytechnic Institute, Troy, New York 12180-3590 (United States); Ambrozewicz, P. [Florida International University, Miami, Florida 33199 (United States); Anciant, E.; Audit, G.; Garcon, M.; Girod, F.X.; Marchand, C. [CEA-Saclay, Service de Physique Nucleaire, F91191 Gif-sur-Yvette (France); Anghinolfi, M. [INFN, Sezione di Genova, 16146 Genova (Italy)] (and others)

2006-02-17T23:59:59.000Z

129

Complete measurement of three-body photodisintegration of {sup 3}He for photon energies between 0.35 and 1.55 GeV  

SciTech Connect (OSTI)

The three-body photodisintegration of {sup 3}He has been measured with the CLAS detector at Jefferson Lab, using tagged photons of energies between 0.35 GeV and 1.55 GeV. The large acceptance of the spectrometer allowed us for the first time to cover a wide momentum and angular range for the two outgoing protons. Three kinematic regions dominated by either two- or three-body contributions have been distinguished and analyzed. The measured cross sections have been compared with results of a theoretical model, which, in certain kinematic ranges, have been found to be in reasonable agreement with the data.

Niccolai, S. [CEA-Saclay, Service de Physique Nucleaire, F91191 Gif-sur-Yvette (France); George Washington University, Washington, DC 20052 (United States); Audit, G.; Laget, J.M.; Marchand, C.; Morand, L.; Morrow, S.A.; Sabatie, F. [CEA-Saclay, Service de Physique Nucleaire, F91191 Gif-sur-Yvette (France); Berman, B.L.; Strauch, S.; Benmouna, N.; Briscoe, W.J.; Dhuga, K.S.; Feldman, G.; Heimberg, P.; Ilieva, Y.Y.; Juengst, H.G.; Lima, A.C.S.; Murphy, L.Y.; O'Rielly, G.V.; Philips, S.A. [George Washington University, Washington, D.C. 20052 (United States)] [and others

2004-12-01T23:59:59.000Z

130

Setting in the Modern Short Story  

E-Print Network [OSTI]

. Thompson , D~'I G. The Ph1losophY ot Fiation. Lo on" l8~. Wh1tcomb , S. L. st of th Novei . Boston, 1 5. II. II. L short-starl: AI 'bright, ].'velyn 1La.Y . Tltle Short story. N. Y., 1 O? Barrett , Chas. P. Short story Writing . N. ., 188. Canby... . III. Matthews, Brander . The Short - st ory. N. :x.., 1 07 . Patton, Wm. International Short-stori e , 2 vols Y., 1 ~lO. Short-stor y Classios--Amerlcan , 5 vols ., N. Y. t 1':;)05 . , , Short-story Clas8~cs--Foreign , 5 vole . N. . ! II...

Hodgson, Elizabeth

1913-06-05T23:59:59.000Z

131

Precise Measurements of Beam Spin Asymmetries in Semi-Inclusive ?0 production  

SciTech Connect (OSTI)

We present studies of single-spin asymmetries for neutral pion electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized hydrogen target, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. A substantial sin ?h amplitude has been measured in the distribution of the cross section asymmetry as a function of the azimuthal angle ?h of the produced neutral pion. The dependence of this amplitude on Bjorken x and on the pion transverse momentum is extracted with significantly higher precision than previous data and is compared to model calculations.

Holtrop, M; Hyde, C E; Ireland, D G; Isupov, E L; Jawalkar, S S; Jenkins, D; Jo, H S; Joo, K; Keller, D; Khandaker, M; Khetarpal, P; Kim, A; Kimy, W; Klein, A; Klein, F J; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, I.J. D.; Markov, N; Mayer, M; McAndrew, J; McKinnon, B; Meyer, C A; Micherdzinska, A.M.; Mokeev, V; Moreno, B; Moutarde, H; Munevar, E; Nadel-Turonski, P; Ni, A; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Sabatio, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Seraydaryan, H; Sharabian, Y G; Smith, G D; Sober, D I; Stepanyan, S S; Stepanyan, S; Stoler, P; Strakovsky, I; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tkachenko, S; Ungaro, M; Voskanyan, H; Voutier, E; Watts, D; Weinstein, L B; Weygand, D P; Wood, M H; Zana, L; Zhang, J; Zhao, B; Zhao, Z W

2011-10-25T23:59:59.000Z

132

A review of "The Writings of an English Sappho" edited by Patricia Phillippy, translated by Jaime Goodrich  

E-Print Network [OSTI]

one of the #23; ve learned daughters of Sir Anthony Cooke in 1540; that the sisters were given a thorough clas- sical education is evidenced by Elizabeth?s numerous poems, epitaphs and inscriptions in Latin and Greek, ably translated for the volume... created a monument to her father and mother that ?makes it clear that Anthony Cooke?s intellectual legacy was car- ried on not by his sons, but by his daughters? (160), yet a#27; rms the daughters as following their mother?s pattern by representing...

Raber, Karen

2012-01-01T23:59:59.000Z

133

Studies of spin-orbit correlations at JLAB  

SciTech Connect (OSTI)

Studies of single spin asymmetries for pion electroproduction in semi-inclusive deep-inelastic scattering are presented using the polarized \\sim6 GeV electrons from at the Thomas Jefferson National Accelerator Facility (JLab) and the Continuous Electron Beam Accelerator Facility (CEBAF) Large Acceptance Spectrometer (CLAS) with the Inner Calorimeter. The cross section versus the azimuthal angle {\\phi}_h of the produced neutral pion has a substantial sin {\\phi}_h amplitude. The dependence of this amplitude on Bjorken x_B and on the pion transverse momentum is extracted and compared with published data.

Mher Aghasyan, Harut Avakian

2011-05-01T23:59:59.000Z

134

Light Vector Meson Photoproduction off of H at Jefferson Lab and rho-omega Interference in the Leptonic Decay Channel  

SciTech Connect (OSTI)

Recent studies of light vector meson production in heavy nuclear targets has generated interest in {rho}-{omega} interference in the leptonic e{sup +}e{sup -} decay channel. An experimental study of the elementary process provides valuable input for theoretical models and calculations. In experiment E04-005 (g12), high statistics photoproduction data has been taken in Jefferson Lab's Hall B with the Cebaf Large Acceptance Spectrometer (CLAS). The invariant mass spectrum is fitted with two interfering relativistic Breit-Wigner functions to determine the interference phase. Preliminary analysis indicate a measurable {rho}-{omega} interference.

Chaden Djalali

2011-12-01T23:59:59.000Z

135

The Forward Tagger facility for low Q{sup 2} experiments at Jefferson Laboratory  

SciTech Connect (OSTI)

Low Q{sup 2} electron scattering is an efficient and competitive experimental technique to provide intense, quasi-real photon beams, with a high degree of linear polarization. Such a technique will be employed in Hall B at Jefferson Laboratory by having the primary 11?GeV electron beam from the CEBAF accelerator impinging on a liquid hydrogen target. Low-angle scattered electrons will be detected with the new Forward Tagger facility, while the final state hadrons will be measured with the CLAS12 spectrometer. The unique combination of the two detectors will permit to carry out a broad physics program, and to explore new possibilities for high quality physics.

Celentano, Andrea [INFN-GENOVA

2014-06-01T23:59:59.000Z

136

Strangeness Suppression in q-qbar Creation Observed in Exclusive Reactions  

E-Print Network [OSTI]

We measured the ratios of electroproduction cross-sections from a proton target for three exclusive meson-baryon final states: $\\Lambda K^+$, $p\\pi^0$, and $n\\pi^+$, with the CLAS detector at Jefferson Lab. Using a simple model of quark hadronization we extract q-qbar creation probabilities for the first time in exclusive two-body production, in which only a single q-qbar pair is created. We observe a sizable suppression of strange quark-antiquark pairs compared to non-strange pairs, similar to that seen in high-energy production.

K. Park; M. D. Mestayer; the CLAS collaboration

2014-12-09T23:59:59.000Z

137

Spin Sum Rules and the Strong Coupling Constant at large distance  

E-Print Network [OSTI]

We present recent results on the Bjorken and the generalized forward spin polarizability sum rules from Jefferson Lab Hall A and CLAS experiments, focusing on the low $Q^2$ part of the measurements. We then discuss the comparison of these results with Chiral Perturbation theory calculations. In the second part of this paper, we show how the Bjorken sum rule with its connection to the Gerasimov-Drell-Hearn sum, allows us to conveniently define an effective coupling for the strong force at all distances.

A. Deur

2009-06-23T23:59:59.000Z

138

Electromagnetic production of hyperon resonances  

E-Print Network [OSTI]

The study of hyperon resonances has entered a new era of precision with advent of high-statistics photoproduction data from the CLAS detector at Jefferson Lab. These data have multi-particle final states, allowing clean identification of exclusive reactions associated with strange mesons and baryons. Examples of physics results are: evidence for isospin interference in the decay of the $\\Lambda(1405)$ resonance; a strong suggestion of meson cloud effects in the structure of the $\\Sigma(1385)$ resonance; data from $K^*$ photoproduction that will test the existence of the purported $K_0(800)$ meson. Properties of other hyperon resonances will also be studied in the near future.

K. Hicks; D. Keller; W. Tang

2010-12-14T23:59:59.000Z

139

Precise Measurements of Beam Spin Asymmetries in Semi-Inclusive ?0 production  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We present studies of single-spin asymmetries for neutral pion electroproduction in semi-inclusive deep-inelastic scattering of 5.776 GeV polarized electrons from an unpolarized hydrogen target, using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility. A substantial sin ?h amplitude has been measured in the distribution of the cross section asymmetry as a function of the azimuthal angle ?h of the produced neutral pion. The dependence of this amplitude on Bjorken x and on the pion transverse momentum is extracted with significantly higher precision than previous data and is compared to model calculations.

Holtrop, M; Hyde, C E; Ireland, D G; Isupov, E L; Jawalkar, S S; Jenkins, D; Jo, H S; Joo, K; Keller, D; Khandaker, M; Khetarpal, P; Kim, A; Kimy, W; Klein, A; Klein, F J; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Kuznetsov, V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, I.J. D.; Markov, N; Mayer, M; McAndrew, J; McKinnon, B; Meyer, C A; Micherdzinska, A.M.; Mokeev, V; Moreno, B; Moutarde, H; Munevar, E; Nadel-Turonski, P; Ni, A; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Park, K; Park, S; Pasyuk, E; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Rosner, G; Sabatio, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Seraydaryan, H; Sharabian, Y G; Smith, G D; Sober, D I; Stepanyan, S S; Stepanyan, S; Stoler, P; Strakovsky, I; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tkachenko, S; Ungaro, M; Voskanyan, H; Voutier, E; Watts, D; Weinstein, L B; Weygand, D P; Wood, M H; Zana, L; Zhang, J; Zhao, B; Zhao, Z W

2011-10-25T23:59:59.000Z

140

CLARA: A Contemporary Approach to Physics Data Processing  

SciTech Connect (OSTI)

In traditional physics data processing (PDP) systems, data location is static and is accessed by analysis applications. In comparison, CLARA (CLAS12 Reconstruction and Analysis framework) is an environment where data processing algorithms filter continuously flowing data. In CLARA's domain of loosely coupled services, data is not stored, but rather flows from one service to another, mutating constantly along the way. Agents, performing event processing, can then subscribe to particular data/events at any stage of the data transformation, and make intricate decisions (e.g. particle ID) by correlating events from multiple, parallel data streams and/or services. This paper presents a PDP application development framework based on service oriented and event driven architectures. This system allows users to design (Java, C++, and Python languages are supported) and deploy data processing services, as well as dynamically compose PDP applications using available services. The PDP service bus provides a layer on top of a distributed pub-sub middleware implementation, which allows complex service composition and integration without writing code. Examples of service creation and deployment, along with the CLAS12 track reconstruction application design will be presented.

V Gyurjyan, D Abbott, J Carbonneau, G Gilfoyle, D Heddle, G Heyes, S Paul, C Timmer, D Weygand, E Wolin

2011-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Data analysis techniques, differential cross sections, and spin density matrix elements for the reaction ? p ? ?p  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

High-statistics measurements of differential cross sections and spin density matrix elements for the reaction ? p--> ?p have been made using the CLAS detector at Jefferson Lab. We cover center-of-mass energies (?s) from 1.97 to 2.84 GeV, with an extensive coverage in the ? production angle. The high statistics of the data sample made it necessary to carefully account for the interplay between the phi natural lineshape and effects of the detector resolution, that are found to be comparable in magnitude. We study both the charged- (?-->K+K- and neutral- (?-K0SK0L) KK? decay modes of the ?. Further, for the charged mode, we differentiate between the cases where the final K-track is directly detected or its momentum reconstructed as the total missing momentum in the event. The two charged-mode topologies and the neutral-mode have different resolutions and are calibrated against each other. Extensive usage is made of kinematic fitting to improve the reconstructed ? mass resolution. Our final results are reported in 10- and mostly 30-MeV-wide ?s bins for the charged- and the neutral-mode, respectively. Possible effects from K+?* channels with pKK? final-states are discussed. These present results constitute the most precise and extensive ? photoproduction measurements to date and in conjunction with the ? photoproduction results recently published by CLAS, will greatly improve our understanding of low energy vector meson photoproduction. ? p --> ?p

Dey, Biplab [Carnegie Mellon Univ., Pittsburgh, PA (United States); Meyer, Curtis A. [Carnegie Mellon Univ., Pittsburgh, PA (United States); Bellis, Matt [Carnegie Mellon Univ., Pittsburgh, PA (United States); Williams, M. [Carnegie Mellon Univ., Pittsburgh, PA (United States)

2014-05-01T23:59:59.000Z

142

Separated Structure Functions for the Exclusive Electroproduction of K+Lambda and K+Sigma0 Final States  

SciTech Connect (OSTI)

We report measurements of the exclusive electroproduction of K{sup +}{Lambda} and K{sup +}{Sigma}{sup 0} final states from a proton target using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The separated structure functions {sigma}{sub T}, {sigma}{sub L},{sigma}{sub TT}, and {sigma}{sub LT} were extracted from the {Phi}- and {epsilon}-dependent differential cross sections taken with electron beam energies of 2.567, 4.056, and 4.247 GeV. This analysis represents the first {sigma}{sub L}/{sigma}{sub T} separation with the CLAS detector, and the first measurement of the kaon electroproduction structure functions away from parallel kinematics. The data span a broad range of momentum transfers from 0.5 {le} Q{sup 2} {le} 2.8 GeV{sup 2} and invariant energy from 1.6 {le} W {le} 2.4 GeV, while spanning nearly the full center-of-mass angular range of the kaon. The separated structure functions reveal clear differences between the production dynamics for the {Lambda} and {Sigma}{sup 0} hyperons. These results provide an unprecedented data sample with which to constrain current and future models for the associated production of strangeness, which will allow for a better understanding of the underlying resonant and non-resonant contributions to hyperon production.

Pawel Ambrozewicz; Daniel Carman; Rob Feuerbach; Mac Mestayer; Brian Raue; Reinhard Schumacher; Avtandil Tkabladze

2006-11-19T23:59:59.000Z

143

Electroexcitation of the Roper resonance for 1.7 < Q**2 < 4.5 -GeV2 in vec-ep ---> en pi+  

SciTech Connect (OSTI)

DOI: http://dx.doi.org/10.1103/PhysRevC.78.045209
The helicity amplitudes of the electroexcitation of the Roper resonance are extracted for 1.7 < Q2 < 4.5 GeV2 from recent high precision JLab-CLAS cross section and longitudinally polarized beam asymmetry data for pi+ electroproduction on protons at W=1.15-1.69 GeV. The analysis is made using two approaches, dispersion relations and a unitary isobar model, which give consistent results. It is found that the transverse helicity amplitude A_{1/2} for the gamma* p -> N(1440)P11 transition, which is large and negative at Q2=0, becomes large and positive at Q2 ~ 2 GeV2, and then drops slowly with Q2. The longitudinal helicity amplitude S_{1/2}, which was previously found from CLAS ep -> eppi0,enpi+ data to be large and positive at Q2=0.4,0.65 GeV2, drops with Q2. Available model predictions for gamma* p -> N(1440)P11 allow us to conclude that these results provide strong evidence in favor of N(1440)P11 as a first radial excitation of

Aznauryan, Inna; Burkert, Volker; Kim, Wooyoung; Park, Kil; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Bagdasaryan, H.; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Batourine, V.; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bookwalter, Craig; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, Wilbert; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cazes, Antoine; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Cords, Dieter; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Cummings, John; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dhamija, Seema; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Donnelly, J.; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Forest, Tony; Fradi, Ahmed; Funsten, Herbert; Gabrielyan, Marianna; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Golovach, Evgeny; Gonenc, Atilla; Gordon, Christopher; Gothe, Ralf; Graham, L.; Griffioen, Keith; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hafnaoui, Khadija; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Kim, Kui; Klein, Andreas; Klein, Andreas; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, Dave; Lee, T.; Lima, Ana; Livingston, Kenneth; Lu, Haiyun; Lukashin, Konstantin; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O'Rielly, Grant; Osipenko, Mikhail; Ostrovidov, Alexander; Park, S.; Pasyuk, Evgueni; Paterson, Craig; Anefalos Pereira, S.; Philips, Sasha; Pierce, Jerome; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Polli, Ermanno; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rowntree, David; Rubin, Philip; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shaw, J.; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham

2008-10-01T23:59:59.000Z

144

Light Vector Mesons in the Nuclear Medium  

SciTech Connect (OSTI)

The light vector mesons ($\\rho$, $\\omega$, and $\\phi$) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the $\\rho$ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to $e^{+}e^{-}$. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The $\\rho$ meson mass spectrum was extracted after the $\\omega$ and $\\phi$ signals were removed in a nearly model-independent way. Comparisons were made between the $\\rho$ mass spectra from the heavy targets ($A > 2$) with the mass spectrum extracted from the deuterium target. With respect to the $\\rho$-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body eff

Wood, Michael; Nasseripour, Rakhsha; Weygand, Dennis; Djalali, Chaden; Tur, Clarisse; Mosel, Ulrich; Muehlich, Pascal; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, James; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Carnahan, Bryan; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dharmawardane, Kahanawita; Dickson, Richard; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gordon, Christopher; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Ronchetti, Federico; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Stepan; Stepanyan, Samuel; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Williams, Michael; Wolin, Elliott; Yegneswaran, Amrit; Zana, Lorenzo; Zhang, Bin; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen

2008-07-01T23:59:59.000Z

145

Observation of a backward peak in the gamma d ---> pi0 d cross- section near the eta threshold  

SciTech Connect (OSTI)

High-quality cross sections for the reaction gamma+d->pi^0+d have been measured using the CLAS at Jefferson Lab over a wide energy range near and above the eta-meson photoproduction threshold. At backward c.m. angles for the outgoing pions, we observe a resonance-like structure near E_gamma=700 MeV. Our model analysis shows that it can be explained by eta excitation in the intermediate state. The effect is the result of the contribution of the N(1535)S_11 resonance to the amplitudes of the subprocesses occurring between the two nucleons and of a two-step process in which the excitation of an intermediate eta meson dominates.

Yordanka Ilieva; Barry Berman; Alexander Kudryavtsev; I.I. Strakovsky; V.E. Tarasov; Moscov Amaryan; Pawel Ambrozewicz; Marco Anghinolfi; G. Asryan; Harutyun Avakian; Hovhannes Baghdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; V. Batourine; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Matthew Bellis; Nawal Benmouna; Angela Biselli; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Volker Crede; R. De Masi; Enzo De Sanctis; Raffaella De Vita; Pavel Degtiarenko; Alexandre Deur; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Kawtar Hafidi; Rafael Hakobyan; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde; Charles Hyde-Wright; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Mikhail Kossov; Zebulun Krahn; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Kenneth Livingston; Haiyun Lu; Marion MacCormick; Nikolai Markov; Bryan McKinnon; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; M. Moteabbed; E. Munevar; Gordon Mutchler; Pawel Nadel-Turonski; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; K. Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Oleg Pogorelko; S. Pozdniakov; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; David Tedeschi; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

2007-05-14T23:59:59.000Z

146

Measurement of ep-->ep[pi]0 beam spin asymmetries above the resonance region  

SciTech Connect (OSTI)

The beam spin asymmetry (BSA) in the exclusive reaction e-vector p-->eppi0 was measured with the CEBAF 5.77 GeV polarized electron beam and Large Acceptance Spectrometer (CLAS). The xB,Q2,t, and phi dependences of the pi0 BSA are presented in the deep inelastic regime. The asymmetries are fitted with a sinphi function and their amplitudes are extracted. Overall, they are of the order of 0.04 0.11 and roughly independent of t. This is the signature of a nonzero longitudinal-transverse interference. The implications concerning the applicability of a formalism based on generalized parton distributions, as well as the extension of a Regge formalism at high photon virtualities, are discussed.

De Masi, Rita; Garcon, Michel; Zhao, Bo; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Ball, J.P.; Ball, Jacques; Ball, James; Baltzell, Nathan; Baturin, Vitaly; Battaglieri, Marco; Bedlinskiy, Ivan; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Bertin, Pierre; Biselli, Angela; Blaszczyk, Lukasz; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crede, Volker; Dashyan, Natalya; De Sanctis, Enzo; De Vita, Raffaella; Degtiarenko, Pavel; Deur, Alexandre; Dharmawardane, Kahanawita; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Donnelly, Joseph; Doughty, David; Dugger, Michael; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feldman, Gerald; Fradi, Ahmed; Funsten, Herbert; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gonenc, Atilla; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Lee, Tsung-Shung; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; Mazouz, Malek; McKinnon, Bryan; Mecking, Bernhard; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Michel, Bernard; Mikhaylov, Konstantin; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Ronchetti, Federico; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Tur, Clarisse; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Voutier, Eric; Watts, Daniel; Weinstein, Lawrence; Weygand, Dennis; Williams, Michael; Wolin, Elliott; Wood, Michael; Yegneswaran, Amrit; Zana, Lorenzo; Zhang, Jixie; Zhao, Zhiwen

2008-04-01T23:59:59.000Z

147

Determination of the Beam-Spin Asymmetry of Deuteron Photodisintegration in the Energy Region $E_?=1.1-2.3$ GeV  

E-Print Network [OSTI]

The beam-spin asymmetry, $\\Sigma$, for the reaction $\\gamma d\\rightarrow pn$ has been measured using the CEBAF Large Acceptance Spectrometer (CLAS) at the Thomas Jefferson National Accelerator Facility (JLab) for six photon-energy bins between 1.1 and 2.3 GeV, and proton angles in the center-of-mass frame, $\\theta_{c.m.}$, between $25^\\circ$ and $160^\\circ$. These are the first measurements of beam-spin asymmetries at $\\theta_{c.m.}=90^\\circ$ for photon-beam energies above 1.6 GeV, and the first measurements for angles other than $\\theta_{c.m.}=90^\\circ$. The angular and energy dependence of $\\Sigma$ is expected to aid in the development of QCD-based models to understand the mechanisms of deuteron photodisintegration in the transition region between hadronic and partonic degrees of freedom, where both effective field theories and perturbative QCD cannot make reliable predictions.

Nicholas Zachariou; Yordanka Ilieva; Nikolay Ya. Ivanov; Misak M Sargsian; Robert Avakian; Gerald Feldman; Pawel Nadel-Turonski; K. P. Adhikari; D. Adikaram; M. D. Anderson; S. Anefalos Pereira; H. Avakian; R. A. Badui; N. A. Baltzell; M. Battaglieri; V. Baturin; I. Bedlinskiy; A. S. Biselli; W. J. Briscoe; W. K. Brooks; V. D. Burkert; T. Cao; D. S. Carman; A. Celentano; S. Chandavar; G. Charles; L. Colaneri; P. L. Cole; N. Compton; M. Contalbrigo; O. Cortes; V. Crede; A. D'Angelo; R. De Vita; E. De Sanctis; A. Deur; C. Djalali; R. Dupre; H. Egiyan; A. El Alaoui; L. El Fassi; L. Elouadrhiri; G. Fedotov; S. Fegan; A. Filippi; J. A. Fleming; T. A. Forest; A. Fradi; N. Gevorgyan; Y. Ghandilyan; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; D. I. Glazier; E. Golovatch; R. W. Gothe; K. A. Griffioen; M. Guidal; K. Hafidi; C. Hanretty; N. Harrison; M. Hattawy; K. Hicks; D. Ho; M. Holtrop; S. M. Hughes; D. G. Ireland; B. S. Ishkhanov; E. L. Isupov; H. Jiang; H. S. Jo; K. Joo; D. Keller; G. Khachatryan; M. Khandaker; A. Kim; W. Kim; F. J. Klein; V. Kubarovsky; P. Lenisa; K. Livingston; H. Y. Lu; I . J . D. MacGregor; N. Markov; P. T. Mattione; B. McKinnon; T. Mineeva; M. Mirazita; V. I. Mokeeev; R. A. Montgomery; H. Moutarde; C. Munoz Camacho; L. A. Net; S. Niccolai; G. Niculescu; I. Niculescu; M. Osipenko; A. I. Ostrovidov; K. Park; E. Pasyuk; W. Phelps; J. J. Phillips; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; Y. Prok; D. Protopopescu; A. J. R. Puckett; M. Ripani; A. Rizzo; G. Rosner; P. Rossi; P. Roy; F. Sabati; C. Salgado; D. Schott; R. A. Schumacher; E. Seder; I. Senderovich; Y. G. Sharabian; Iu. Skorodumina; G. D. Smith; D. I. Sober; D. Sokhan; N. Sparveris; S. Stepanyan; S. Strauch; V. Sytnik; M. Taiuti; Ye Tian; M. Ungaro; H. Voskanyan; E. Voutier; N. K. Walford; D. Watts; X. Wei; M. H. Wood; L. Zana; J. Zhang; Z. W. Zhao; I. Zonta; for the CLAS collaboration

2015-03-18T23:59:59.000Z

148

Isospin analysis of Theta+ production forbids gamma p ---> Theta+ K(s) and allows gamma n ---> Theta+ K-.  

E-Print Network [OSTI]

ar X iv :h ep -p h/ 05 06 08 4v 3 1 6 Ju n 20 05 Cavendish-HEP-05/09 TAUP 2807/05 ANL-HEP-PR-05-47 Isospin Analysis of ?+ production forbids ?p ? ?+ Ks and allows ?n ? ?+ K? Marek Karliner a,b? and Harry J. Lipkin b,c a Cavendish Laboratory... .g. comparing ?p ? pK+K? with the analogous reaction with neutral kaons in the final state. One can also do an analogous comparison in ?d. The relevant data might in principle be available in the CLAS g11 and LEPS experiments. We also note that the ?KoKo vertex...

Karliner, Marek; Lipkin, Harry J

149

First measurement of coherent $\\phi$-meson photoproduction on deuteron at low energies  

SciTech Connect (OSTI)

The cross section and decay angular distributions for the coherent \\phi meson photoproduction on the deuteron have been measured for the first time up to a squared four-momentum transfer t =(p_{\\gamma}-p_{\\phi})^2 =-2 GeV^2/c^2, using the CLAS detector at the Thomas Jefferson National Accelerator Facility. The cross sections are compared with predictions from a re-scattering model. In a framework of vector meson dominance, the data are consistent with the total \\phi-N cross section \\sigma_{\\phi N} at about 10 mb. If vector meson dominance is violated, a larger \\sigma_{\\phi N} is possible by introducing larger t-slope for the \\phi N \\to \\phi N process than that for the \\gamma N \\to \\phi N process. The decay angular distributions of the \\phi are consistent with helicity conservation.

Tsutomu Mibe; Haiyan Gao; Kenneth Hicks; Kevin Kramer; Stepan Stepanyan; David Tedeschi; Moscov Amaryan; Pawel Ambrozewicz; Marco Anghinolfi; G. Asryan; Gerard Audit; Harutyun Avakian; Hovhannes Baghdasaryan; Nathan Baillie; Jacques Ball; Nathan Baltzell; Marco Battaglieri; Ivan Bedlinski; Ivan Bedlinskiy; Matthew Bellis; Nawal Benmouna; Barry Berman; Angela Biselli; Lukasz Blaszczyk; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Shifeng Chen; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; Volker Crede; John Cummings; Natalya Dashyan; Rita De Masi; Raffaella De Vita; Enzo De Sanctis; Pavel Degtiarenko; Alexandre Deur; Kahanawita Dharmawardane; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Lamiaa Elfassi; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Gerald Feldman; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; Charles Hanretty; John Hardie; F. Hersman; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; David Jenkins; Hyon-Suk Jo; John Johnstone; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mikhail Kossov; Zebulun Krahn; Laird Kramer; V. Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Viacheslav Kuznetsov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Ji Li; Kenneth Livingston; Haiyun Lu; Marion MacCormick; Claude Marchand; Nikolai Markov; Paul Mattione; Bryan McKinnon; Bernhard Mecking; Joseph Melone; Mac Mestayer; Curtis Meyer; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; M. Moteabbed; E. Munevar; Gordon Mutchler; P. Nadel-Turonski; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; K. Park; Evgueni Pasyuk; Craig Paterson; S. Anefalos Pereira; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; S. Pozdniakov; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Dmitri Sharov; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Daria Sokhan; A. Stavinsky; Samuel Stepanyan; B.E. Stokes; Paul Stoler; I.I. Strakovsky; Steffen Strauch; Mauro Taiuti; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Daniel Watts; Lawrence Weinstein; Dennis Weygand; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

2007-11-01T23:59:59.000Z

150

pi0 photoproduction on the proton for photon energies from 0.675 to 2.875-GeV  

SciTech Connect (OSTI)

Differential cross sections for the reaction $\\gamma p \\to p \\pi^0$ have been measured with the CEBAF Large Acceptance Spectrometer (CLAS) and a tagged photon beam with energies from 0.675 to 2.875 GeV. The results reported here possess greater accuracy in the absolute normalization than previous measurements. They disagree with recent CB-ELSA measurements for the process at forward scattering angles. Agreement with the SAID and MAID fits is found below 1 GeV. The present set of cross sections has been incorporated into the SAID database, and exploratory fits have been extended to 3 GeV. Resonance couplings have been extracted and compared to previous determinations.

Michael Dugger; Barry Ritchie; Jacques Ball; Patrick Collins; Evgueni Pasyuk; Richard Arndt; William Briscoe; Igor Strakovski; Ron Workman; Gary Adams; Moscov Amaryan; Pawel Ambrozewicz; Eric Anciant; Marco Anghinolfi; Burin Asavapibhop; G. Asryan; Gerard Audit; Harutyun Avakian; H. Bagdasaryan; Nathan Baillie; Nathan Baltzell; Steve Barrow; Marco Battaglieri; Kevin Beard; Ivan Bedlinski; Ivan Bedlinskiy; Mehmet Bektasoglu; Matthew Bellis; Nawal Benmouna; Barry Berman; Nicola Bianchi; Angela Biselli; Billy Bonner; Sylvain Bouchigny; Sergey Boyarinov; Robert Bradford; Derek Branford; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Bryan Carnahan; Shifeng Chen; Philip Cole; Alan Coleman; Philip Coltharp; Dieter Cords; Pietro Corvisiero; Donald Crabb; Hall Crannell; John Cummings; Enzo De Sanctis; Raffaella De Vita; Pavel Degtiarenko; Haluk Denizli; Lawrence Dennis; Alexandre Deur; Kahanawita Dharmawardane; Kalvir Dhuga; Richard Dickson; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; P. Dragovitsch; Steven Dytman; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Latifa Elouadrhiri; A. Empl; Paul Eugenio; Renee Fatemi; Gleb Fedotov; Gerald Feldman; Robert Feuerbach; John Ficenec; Tony Forest; Herbert Funsten; Michel Garcon; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; John Goetz; Ralf Gothe; Keith Griffioen; Michel Guidal; Matthieu Guillo; Nevzat Guler; Lei Guo; Vardan Gyurjyan; Cynthia Hadjidakis; Rafael Hakobyan; John Hardie; D. Heddle; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; J. Hu; Marco Huertas; Charles Hyde; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Mark Ito; David Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; Narbe Kalantarians; James Kellie; Mahbubul Khandaker; Kui Kim; Kinney Kim; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mike Klusman; Mikhail Kossov; Zebulun Krahn; Laird Kramer; Valery Kubarovsky; Joachim Kuhn; Sebastian Kuhn; Viacheslav Kuznetsov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; David Lawrence; Tsung-shung Lee; Ana Lima; Kenneth Livingston; K. Lukashin; Joseph Manak; Claude Marchand; Leonard Maximon; Simeon McAleer; Bryan McKinnon; John McNabb; Bernhard Mecking; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; Rory Miskimen; Viktor Mokeev; Kei Moriya; Steven Morrow; Valeria Muccifora; James Mueller; Gordon Mutchler; Pawel Nadel-Turonski; James Napolitano; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Grant O'Rielly; Mikhail Osipenko; Alexander Ostrovidov; K Park; Craig Paterson; Sasha Philips; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; S. Pozdniakov; Barry Preedom; John Price; Yelena Prok; Dan Protopopescu; Liming Qin; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; David Rowntree; Philip Rubin; Franck Sabatie; Julian Salamanca; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Aziz Shafi; Youri Sharabian; J. Shaw; Sebastio Simionatto; Alexander Skabelin; Elton Smith; Lee Smith; Daniel Sober; M. Spraker; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Paul Stoler; Steffen Strauch; Mauro Taiuti; Simon Taylor; David Tedeschi; Ulrike Thoma; R. Thompson; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Maurizio Ungaro; Michael Vineyard; Alexander Vlassov; Xue kai Wang; Lawrence Weinstein; Henry Weller; Dennis Weygand; M. Williams; Elliott Wolin; M.H. Wood; A. Yegneswaran; Jae-Chul Yun; Lorenzo Zana; Jixie Zhang

2007-07-23T23:59:59.000Z

151

Measurement Of Differential Cross Sections Of p(e,e'{pi}{sup +})n For High-Lying Resonances At Q{sup 2} < 5 GeV{sup 2}  

SciTech Connect (OSTI)

The exclusive electro-production process ep -> e'n{pi}{sup +} was measured in the range of the invariant mass for n{pi}{sup +} system 1.6 GeV <= W <= 2.0 GeV, and the photon virtuality 1.8 GeV{sup 2} <= Q{sup 2} <= 4.0 GeV{sup 2} using CLAS. For the first time, these kinematics are probed in exclusive {pi}{sup +} production from the protons with nearly full coverage in the azimuthal and polar angles of the n{pi}{sup +} center-of-mass system. In this experiment, approximately 39,000 differential cross-section data points were measured. In this proceeding, preliminary results of our latest analysis work are presented on differential cross sections and structure functions as well as Legendre Moments.

Park, Kijun

2014-01-01T23:59:59.000Z

152

Spin and parity measurement of the ?(1405) baryon  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

A determination of the spin and parity of the ?(1405) is presented using photoproduction data from the CLAS detector at Jefferson Lab. The reaction ?+p?K++?(1405) is analyzed in the decay channel Lambda(1405)??++?, where the decay distribution to ?+pi- and the variation of the ?+ polarization with respect to the ?(1405) polarization direction determines the parity. The ?(1405) is produced, in the energy range 2.55

Moriya, Kei [Indiana U.; Schumacher, Reinhard A. [Carnegie Mellon U.

2014-02-01T23:59:59.000Z

153

Differential Photoproduction Cross Sections of the Sigma0(1385), Lambda(1405), and Lambda(1520)  

SciTech Connect (OSTI)

We report the exclusive photoproduction cross sections for the Sigma(1385), Lambda(1405), and Lambda(1520) in the reactions gamma + p -> K+ + Y* using the CLAS detector for energies from near the respective production thresholds up to a center-of-mass energy W of 2.85 GeV. The differential cross sections are integrated to give the total exclusive cross sections for each hyperon. Comparisons are made to current theoretical models based on the effective Lagrangian approach and fitted to previous data. The accuracy of these models is seen to vary widely. The cross sections for the Lambda(1405) region are strikingly different for the Sigma+pi-, Sigma0 pi0, and Sigma- pi+ decay channels, indicating the effect of isospin interference, especially at W values close to the threshold.

Moriya, Kei [Indiana U.; Schumacher, Reinhard A. [Carnegie Mellon U.

2013-10-01T23:59:59.000Z

154

Isospin Decomposition of the Photoproduced Sigma pi System Near the Lambda(1405)  

SciTech Connect (OSTI)

Recent experimental results for the reaction \\gamma + p \\to K^+ + \\Sigma + \\pi\\ from CLAS at Jefferson Lab are discussed. It was found that the mass distributions or "line shapes" of the three charge combinations \\Sigma^+ \\pi^-, \\Sigma^0 \\pi^0 and \\Sigma^- \\pi^+ differ significantly. Our results show that the \\Lambda(1405), as the I=0 constituent of the reaction, must be accompanied by an I > 0 component. We discuss phenomenological fits to the data to test the possible forms and magnitudes of these amplitudes. A two-amplitude I=0 fit of Breit-Wigner form to the \\Sigma^0\\pi^0 channel alone works quite well. The addition of a single I=1 amplitude works fairly well to model all the line shapes simultaneously.

Carnegie Mellon U.; Indiana U.

2013-09-01T23:59:59.000Z

155

Electroproduction of $?$(1405)  

SciTech Connect (OSTI)

The electroproduction of K{sup +} {Lambda}(1405) was studied by analyzing the E1F data set collected in Hall B at Jefferson Lab. The analysis utilized the decay channel {Sigma}{sup +} {pi}{sup -} of the {Lambda}(1405) and p{pi}{sup 0} of the {Sigma}{sup +}. Simulations of background, {Lambda}(1405) and {Lambda}(1520) production according to PDG values were performed by using standard CLAS analysis tools adapted for the E1F run. Fits of the acceptance-corrected simulations were made to the acceptance-corrected data to determine contributions from signal and background processes. The line shape of {Lambda}(1405) varies with the four momentum transfer, Q{sup 2}, and does not match the line shape based on PDG resonance parameters. It corresponds approximately to predictions of a recent two-pole meson-baryon picture of this state.

Haiyun Lu, Reinhard Schumacher, Brian Raue, Marianna Gabrielyan

2012-04-01T23:59:59.000Z

156

The In-medium Mass and Widths of Light Vector Mesons  

SciTech Connect (OSTI)

Partial restoration of chiral symmetry in ordinary nuclear matter suggests the modification of properties of vector mesons, such as a shift in mass and/or a change of width. Photoproduction of vector mesons off nuclei were performed at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). The properties of the {rho}, {omega} and {phi} mesons were investigated via their rare leptonic decay to e+e-. This decay channel has an advantage over hadronic modes as it eliminates final state interactions in the nuclear matter. After subtracting the combinatorial background, the meson mass distributions were extracted for each of the nuclear targets. No significant mass shift is observed, however substantial increase in the widths of the mesons is reported.

Djalali, C.; Paolone, M. [University of South Carolina, Department of Physics and Astronomy, Columbia, SC 29208 (United States); Weygand, D. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23606 (United States); Wood, M. H. [Canisius College, Department of Physics, Buffalo, NY 14208 (United States); Nasseripour, R. [George Washington University, Department of Physics, Washington, DC 20052 (United States)

2011-05-23T23:59:59.000Z

157

Precision measurements of $g_1$ of the proton and the deuteron with 6 GeV electrons  

E-Print Network [OSTI]

The inclusive polarized structure functions of the proton and deuteron, g1p and g1d, were measured with high statistical precision using polarized 6 GeV electrons incident on a polarized ammonia target in Hall B at Jefferson Laboratory. Electrons scattered at lab angles between 18 and 45 degrees were detected using the CEBAF Large Acceptance Spectrometer (CLAS). For the usual DIS kinematics, Q^2>1 GeV^2 and the final-state invariant mass W>2 GeV, the ratio of polarized to unpolarized structure functions g1/F1 is found to be nearly independent of Q^2 at fixed x. Significant resonant structure is apparent at values of W up to 2.3 GeV. In the framework of perturbative QCD, the high-W results can be used to better constrain the polarization of quarks and gluons in the nucleon, as well as high-twist contributions.

Y. Prok; P. Bosted; N. Kvaltine; K. P. Adhikari; D. Adikaram; M. Aghasyan; M. J. Amaryan; M. D. Anderson; S. Anefalos Pereira; H. Avakian; H. Baghdasaryan; J. Ball; N. A. Baltzell; M. Battaglieri; A. S. Biselli; J. Bono; W. J. Briscoe; J. Brock; W. K. Brooks; S. Bltmann; V. D. Burkert; C. Carlin; D. S. Carman; A. Celentano; S. Chandavar; L. Colaneri; P. L. Cole; M. Contalbrigo; O. Cortes; D. Crabb; V. Crede; A. D'Angelo; N. Dashyan; R. De Vita; E. De Sanctis; A. Deur; C. Djalali; G. E. Dodge; D. Doughty; R. Dupre; A. El Alaoui; L. El Fassi; L. Elouadrhiri; G. Fedotov; S. Fegan; R. Fersch; J. A. Fleming; T. A. Forest; M. Garcon; N. Gevorgyan; Y. Ghandilyan; G. P. Gilfoyle; F. X. Girod; K. L. Giovanetti; J. T. Goetz; W. Gohn; R. W. Gothe; K. A. Griffioen; B. Guegan; N. Guler; K. Haffidi; C. Hanretty; N. Harrison; M. Hattawy; K. Hicks; D. Ho; M. Holtrop; Y. Ilieva; D. G. Ireland; B. S. Ishkhanov; E. L. Isupov; S. Jawalkar; X. Jiang; H. S. Jo; K. Joo; N. Kalantarians; C. Keith; D. Keller; M. Khandaker; A. Kim; W. Kim; A. Klein; F. J. Klein; S. Koirala; V. Kubarovsky; S. E. Kuhn; S. V. Kuleshov; P. Lenisa; K. Livingston; H. Y. Lu; I . J. D. MacGregor; N. Markov; M. Mayee; B. McKinnon; D. Meekins; T. Mineeva; M. Mirazita; V. Mokeev; R. A. Montgomery; H. Moutarde; A Movsisyan; E. Munevar; C. Munoz Camacho; P. Nadel-Turonski; S. Niccolai; G. Niculescu; I. Niculescu; M. Osipenko; A. I. Ostrovidov; L. L. Pappalardo; R. Paremuzyan; K. Park; P. Peng; J. J. Phillips; J. Pierce; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; D. Protopopescu; A. J. R. Puckett; B. A. Raue; D. Rimal; M. Ripani; A. Rizzo; G. Rosner; P. Rossi; P. Roy; F. Sabati; M. S. Saini; C. Salgado; D. Schott; R. A. Schumacher; E. Seder; Y. G. Sharabian; A. Simonyan; C. Smith; G. Smith; D. I. Sober; D. Sokhan; S. S. Stepanyan; S. Stepanyan; I. I. Strakovsky; S. Strauch; V. Sytnik; M. Taiuti; W. Tang; S. Tkachenko; M. Ungaro; B . Vernarsky; A. V. Vlassov; H. Voskanyan; E. Voutier; N. K. Walford; D . P. Watts; L. B. Weinstein; N. Zachariou; L. Zana; J. Zhang; B. Zhao; Z. W. Zhao; I. Zonta; for the CLAS collaboration

2014-04-24T23:59:59.000Z

158

K{sub S} Lambda Photoproduction On The Neutron Within The Resonance Region  

SciTech Connect (OSTI)

We report some preliminary differential cross section results for the gammad --> K{sub S} Lambda(p) reaction using a circularly-polarized photon beam and an unpolarized LD{sub 2} target. The data was collected at the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. For this study the photon energy ranged from 1.3 to 2.53 GeV, which covers from the reaction threshold through the nucleon resonance regimes. The acceptance- and flux-corrected yields show peaks at the center-of mass energies W = 1.7 and W = 1.9 GeV. These first-time results will aid in unraveling the spectrum of non-strange excited baryons.

Taylor, Charles E. [Idaho State University, Pocatello, ID (United States); Cole, Philip L. [Idaho State University, Pocatello, ID (United States)

2014-01-01T23:59:59.000Z

159

Probing the nucleon structure with SIDIS at Jefferson Lab  

SciTech Connect (OSTI)

In recent years, measurements of azimuthal moments of polarized hadronic cross sections in hard processes have emerged as a powerful tool to probe nucleon structure. Many experiments worldwide are currently trying to pin down various effects related to nucleon structure through Semi-Inclusive Deep-Inelastic Scattering (SIDIS). Azimuthal distributions of final-state particles in semi-inclusive deep inelastic scattering, in particular, are sensitive to the orbital motion of quarks and play an important role in the study of Transverse Momentum Dependent parton distribution functions (TMDs) of quarks in the nucleon. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected semi-inclusive data using the CEBAF 6 GeV polarized electron beam on polarized solid NH{sub 3} and ND{sub 3} targets. An overview of these measurements is presented.

Pereira, Sergio Anafalos [INFN-Frascati

2013-01-01T23:59:59.000Z

160

Upper limits for the photoproduction cross section for the Phi--(1860) pentaquark state off the deuteron  

SciTech Connect (OSTI)

We searched for the {Phi}{sup --}(1860) pentaquark in the photoproduction process off the deuteron in the {Xi}{sup -} {pi}{sup -} decay channel using CLAS. The invariant mass spectrum of the {Xi}{sup -} {pi}{sup -} system does not indicate any statistically significant enhancement near the reported mass M = 1.860 GeV. The statistical analysis of the sideband-subtracted mass spectrum yields a 90% confidence level upper limit of 0.7 nb for the photoproduction cross section of {Phi}{sup --}(1860) with a consecutive decay into {Xi}{sup -} {pi}{sup -} in the photon energy range 4.5 GeV < E{sub {gamma}} < 5.5 GeV.

Hovanes Egiyan

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Light Vector Meson Photoproduction off of 1H at Jefferson Lab and p-w Interference in the Leptonic Decay Channel  

SciTech Connect (OSTI)

Although the phenomena of r w interference has been studied at great length in pionic decay channel over the past 50 years, a study of the interference in a purely electromagnetic production and decay channel has never been performed on an elementary proton target until now. The only published photo-production data of the r - w leptonic decay channel was obtained in the early seventies on C and Be. An investigation of the r - w interference on a Hydrogen was recently completed at Jefferson Lab with the CLAS detector. The di-lepton spectra was fit with two inter- fering relativistic Breit-Wigner functions, and the interference phase was extracted. Preliminary results will be compared to the previous experimental studies in nuclei.

Djalali, Chaden [University of Iowa; Paolone, Michael [Temple University, JLAB; Weygand, Dennis; Wood, Mike H. [USC LA, JLAB

2014-09-01T23:59:59.000Z

162

Cross Sections for the $\\gamma p \\to K^{*0}\\Sigma^+$ Reaction at $E_\\gamma = 1.7 - 3.0$ GeV  

SciTech Connect (OSTI)

Differential cross sections for the reaction $\\gamma p \\to K^{*0} \\Sigma^+$ are presented at nine bins in photon energy in the range from 1.7 to 3.0 GeV. The \\kstar was detected by its decay products, $K^+\\pi^-$, in the CLAS detector at Jefferson Lab. These data are the first \\kstar photoproduction cross sections ever published over a broad range of angles. Comparison with a theoretical model based on the vector and tensor $K^*$-quark couplings shows good agreement with the data in general, after adjusting the model's two parameters in a fit to our data. Disagreement between the data at forward angles and the global angle-energy fit to the model suggests that the role of scalar $\\kappa$ meson exchange in $t$-channel diagrams should be investigated.

I. Hleiqawi; K. Hicks; D.Carman; T.Mibe

2007-04-01T23:59:59.000Z

163

Precision measurements of g1 of the proton and the deuteron with 6 GeV electrons  

SciTech Connect (OSTI)

The inclusive polarized structure functions of the proton and deuteron, g1p and g1d, were measured with high statistical precision using polarized 6 GeV electrons incident on a polarized ammonia target in Hall B at Jefferson Laboratory. Electrons scattered at lab angles between 18 and 45 degrees were detected using the CEBAF Large Acceptance Spectrometer (CLAS). For the usual DIS kinematics, Q^2>1 GeV^2 and the final-state invariant mass W>2 GeV, the ratio of polarized to unpolarized structure functions g1/F1 is found to be nearly independent of Q^2 at fixed x. Significant resonant structure is apparent at values of W up to 2.3 GeV. In the framework of perturbative QCD, the high-W results can be used to better constrain the polarization of quarks and gluons in the nucleon, as well as high-twist contributions.

Prok, Yelena; Bosted, Peter; Kvaltine, Nicholas; Adhikari, Krishna; Adikaram-Mudiyanselage, Dasuni; Aghasyan, Mher; Amaryan, Moskov; Anderson, Mark; Anefalos Pereira, Sergio; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Biselli, Angela; Bono, Jason; Briscoe, William; Brock, Joseph; Brooks, William; Bueltmann, Stephen; Burkert, Volker; Carlin, Christopher; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Colaneri, Luca; Cole, Philip; Contalbrigo, Marco; Cortes, Olga; Crabb, Donald; Crede, Volker; D'Angelo, Annalisa; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Dodge, Gail; Doughty, David; Dupre, Raphael; El Alaoui, Ahmed; El Fassi, Lamiaa; Elouadrhiri, Latifa; Fedotov, Gleb; Fegan, Stuart; Fersch, Robert; Fleming, Jamie; Forest, Tony; Garcon, Michel; Gevorgyan, Nerses; Ghandilyan, Yeranuhi; Gilfoyle, Gerard; Girod-Gard, Francois-Xavier; Giovanetti, Kevin; Goetz, John; Gohn, Wesley; Gothe, Ralf; Griffioen, Keith; Guegan, Baptiste; Guler, Nevzat; Hafidi, Kawtar; Hanretty, Charles; Harrison, Nathan; Hattawy, Mohammad; Hicks, Kenneth; Ho, Dao; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Jawalkar, Sucheta; Jiang, Xiaodong; Jo, Hyon-Suk; Joo, Kyungseon; Kalantarians, Narbe; Keith, Christopher; Keller, Daniel; Khandaker, Mahbubul; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Koirala, Suman; Kubarovsky, Valery; Kuhn, Sebastian; Kuleshov, Sergey; Lenisa, Paolo; Livingston, Kenneth; Lu, Haiyun; MacGregor, Ian; Markov, Nikolai; Mayer, Michael; McKinnon, Bryan; Meekins, David; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Montgomery, Rachel; MOUTARDE, Herve; Movsisyan, Aram; Munevar Espitia, Edwin; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria; Osipenko, Mikhail; Ostrovidov, Alexander; Pappalardo, Luciano; Paremuzyan, Rafayel; Park, K.; Peng, Peng; Phillips, J.J.; Pierce, Joshua; Pisano, Silvia; Pogorelko, Oleg; Pozdniakov, Serguei; Price, John; Procureur, Sebastien; Protopopescu, Dan; Puckett, Andrew; Raue, Brian; Rimal, Dipak; Ripani, Marco; Rizzo, Alessandro; Rosner, Guenther; Rossi, Patrizia; Roy, Priyashree; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Sharabian, Youri; Simonyan, Ani; Smith, Claude; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Stepan; Stepanyan, Samuel; Strakovski, Igor; Strauch, Steffen; Sytnik, Valeriy; Taiuti, Mauro; Tang, Wei; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vernarsky, Brian; Vlasov, Alexander; Voskanyan, Hakob; Voutier, Eric; Walford, Natalie; Watts, Daniel; Weinstein, Lawrence; Zachariou, Nicholas; Zana, Lorenzo; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen; Zonta, Irene

2014-08-01T23:59:59.000Z

164

Electromagnetic Decay of the $\\Sigma^{0}(1385)$ to $\\Lambda\\gamma$  

SciTech Connect (OSTI)

The electromagnetic decay $\\Sigma^0(1385) \\to \\Lambda \\gamma$ was studied using the CLAS detector at the Thomas Jefferson National Accelerator Facility. A real photon beam with a maximum energy of 3.8 GeV was incident on a proton target, producing an exclusive final state of $K^+\\Sigma^{*0}$. We report the decay widths ratio $\\Sigma^0(1385) \\to \\Lambda\\gamma$/ $\\Sigma^0(1385) \\to \\Lambda\\pi^0$ = $1.42 \\pm 0.12(\\text{stat})_{-0.07}^{+0.11}(\\text{sys})$%. This ratio is larger than most theoretical predictions by factors ranging from 1.5-3, but is consistent with the only other experimental measurement. From the reported ratio we calculate the partial width and electromagnetic transition magnetic moment for $\\Sigma^0(1385) \\to \\Lambda\\gamma$.

Keller, Dustin; Adhikari, Krishna; Adikaram-Mudiyanselage, Dasuni; Aghasyan, Mher; Amaryan, Moscov; Baghdasaryan, Hovhannes; Ball, J P; Ball, Jacques; Battaglieri, Marco; Batourine, V; Bedlinskiy, Ivan; Bennett, Robert; Biselli, Angela; Branford, Derek; Briscoe, Wilbert; Brooks, William; Burkert, Volker; Careccia, Sharon; Carman, Daniel; Casey, Liam; Cole, Philip; Contalbrigo, Marco; Crede, Volker; D& #x27; Angelo, Annalisa; Daniel, AJI; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Dey, Biplap; Dickson, Richard; Djalali, Chaden; Doughty, David; Dupre, Raphael; Egiyan, Hovanes; El Alaoui, Ahmed; Elfassi, Lamiaa; Eugenio, Paul; Fedotov, Gleb; Fegan, Stuart; Forest, Tony; Gabrielyan, Marianna; Gavalian, Gagik; Gevorgyan, Nerses; Giovanetti, Kevin; Girod, Francois-Xavier; Gohn, Wesley; Golovach, Evgeny; Gothe, Ralf; Graham, Lewis; Guidal, Michel; Guegan, Baptiste; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Isupov, Evgeny; Jawalkar, Sucheta; Jenkins, David; Jo, Hyon-Suk; Joo, Kyungseon; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Andrey; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Konczykowski, Piotr; Kubarovsky, Valery; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lu, Haiyun; MacGregor, Ian; Markov, Nikolai; McAndrew, Josephine; KcKinnon, Bryan; Meyer, Curtis; Micherdzinska, Anna; Mirazita, Marco; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrison, Brian; Moutarde, Herve; Munevar Espitia, Edwin; Nadel-Turonski, Pawel; Ni, Andrey; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Osipenko, Mikhail; Ostrovidov, Alexander; Paremuzyan, Rafayel; Park, Kijun; Park, Sungkyun; Pasyuk, Eugene; Pasyuk, Evgueni; Pereira, Sergio; Pappalardo, Luciano; Pisano, Silvia; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Procureur, Sebastien; Protopopescu, Dan; Raue, Brian; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Seraydaryan, Heghine; Sharabian, Youri; Smith, Elton; Smith, Gregory; Sober, Daniel; Stepanyan, Stepan; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tang, Wei; Taylor, Charles; Vernarsky, Brian; Vineyard, Michael; Voutier, Eric; Weinstein, Lawrence; Watts, Daniel; Wood, Michael; Zachariou, Nicholas; Zana, Lorenzo; Zhao, Bo

2011-04-01T23:59:59.000Z

165

Measurement of the generalized form factors near threshold via ?*p ? n?+ at high Q2  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

We report the first extraction of the pion-nucleon multipoles near the production threshold for the n?+ channel at relatively high momentum transfer (Q2 up to 4.2 GeV2). The dominance of the s-wave transverse multipole (E0+), expected in this region, allowed us to access the generalized form factor G1 within the light-cone sum rule (LCSR) framework as well as the axial form factor GA. The data analyzed in this work were collected by the nearly 4? CEBAF Large Acceptance Spectrometer (CLAS) using a 5.754-GeV electron beam on a proton target. The differential cross section and the ?-N multipole E0+/GD were measured using two different methods, the LCSR and a direct multipole fit. The results from the two methods are found to be consistent and almost Q2 independent.

Park, K; Adhikari, K P; Adikaram, D; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Batourine, V; Bedlinskiy, I; Bennett, R P; Biselli, A S; Bookwalter, C; Boiarinov, S; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Crede, V; D'Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Doughty, D; Dupre, R; El Alaoui, A; El Fassi, L; Euginio, P; Fedotov, G; Fradi, A; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Golovatch, E; Graham, L; Griffioen, K A; Guidal, M; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Heddle, D; Hicks, K; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jenkins, D; Jo, H S; Joo, K; Khandaker, M; Khertarpal, P; Kim, A; Kim, W; Klein, F J; Kubarovsky, A; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, J D; Markov, N; Mayer, M; McKinnon, B; Mestayer, M D; Meyer, C A; Mineeva, T; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Park, S; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Ricco, G; Rimal, D; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabati ee, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tian, Y; Tkachenko, S; Trivedi, A; Ungaro, M; Vernarsky, B; Vlassov, A V; Voutier, E; Watts, D P; Weygand, D P; Wood, M H; Zachariou, N; Zhao, B; Zhao, Z W

2012-03-26T23:59:59.000Z

166

Differential cross section of gamma n to K+ Sigma- on bound neutrons with incident photons from 1.1 to 3.6 GeV  

E-Print Network [OSTI]

Differential cross sections of the reaction gamma d to K+ Sigma- (p) have been measured with the CLAS detector at Jefferson Lab using incident photons with energies between 1.1 and 3.6 GeV. This is the first complete set of strangeness photoproduction data on the neutron covering a broad angular range. At energies close to threshold and up to E_gamma ~ 1.8 GeV, the shape of the angular distribution is suggestive of the presence of s-channel production mechanisms. For E_gamma > 1.8 GeV, a clear forward peak appears and becomes more prominent as the photon energy increases, suggesting contributions from t-channel production mechanisms. These data can be used to constrain future analysis of this reaction.

S. Anefalos Pereira; M. Mirazita; P. Rossi; E. De Sanctis; G. Niculescu; I. Niculescu; S. Stepanyan; for the CLAS Collaboration

2010-02-03T23:59:59.000Z

167

The internal structures of the nucleon resonances $N(1875)$ and $N(2120)$  

E-Print Network [OSTI]

A nucleon resonance with spin-parity $J^P=3/2^-$ and mass about 2.1 GeV is essential to reproduce the photoproduction cross sections for $\\Lambda(1520)$ released by the LEPS and CLAS Collaborations. It can be explained as the third nucleon resonance state $[3/2^-]_3$ in the constituent quark model so that there is no position to settle the $N(1875)$ which is listed in the PDG as the third $N3/2^-$ nucleon resonance. An interpretation is proposed that the $N(1875)$ is from the interaction of a decuplet baryon $\\Sigma(1385)$ and a octet meson $K$, which is favored by a calculation of binding energy and decay pattern in a Bethe-Salpeter approach.

He, Jun

2015-01-01T23:59:59.000Z

168

Nuclear physics research at the University of Richmond. Progress report, November 1, 1994--October 31, 1995  

SciTech Connect (OSTI)

Summarized in this report is the progress achieved during the period from November 1, 1994 to October 31, 1995. The experimental work described in this report is in electromagnetic and heavy-ion nuclear physics. The effort in electromagnetic nuclear physics is in preparation for the research program at the Continuous Electron Beam Accelerator Facility (CEBAF) and is focused on the construction and use of the CEBAF Large Acceptance Spectrometer (CLAS). The heavy-ion experiments were performed at the Argonne National Laboratory ATLAS facility and SUNY, Stony Brook. The physics interests driving these efforts at CEBAF are in the study of the structure, interactions, and nuclear-medium modifications of mesons and baryons. This year, an extension of the experiment to measure the magnetic form factor of the neutron was approved by the CEBAF Program Advisory Committee Nine (PAC9) for beam at 6 GeV. The authors also submitted updates to PAC9 on the experiments to measure inclusive {eta} photoproduction in nuclei and electroproduction of the {Lambda}, {Lambda}*(1520), and f{sub 0}(975). In addition to these experiments, the authors collaborated on a proposal to measure rare radiative decays of the {phi} meson which was also approved by PAC9. Their contributions to the construction of the CLAS include the development of the drift-chamber gas system, drift-chamber software, and controls software. Major has been leading the effort in the construction of the gas system. In the last year, the Hall B gas shed was constructed and the installation of the gas system components built at the University of Richmond has begun. Over the last six years, the efforts in low-energy heavy-ion physics have decreased due to the change in focus to electromagnetic nuclear physics at CEBAF. Most of the heavy-ion work is completed and there are now new experiments planned. Included in this report are two papers resulting from collaborations on heavy-ion experiments.

Vineyard, M.F.; Gilfoyle, G.P.; Major, R.W.

1995-12-31T23:59:59.000Z

169

Study of the Two-pion Photoproduction on the Deuteron  

SciTech Connect (OSTI)

Understanding the structure of baryons in terms of the fundamental interaction of the constituent quarks and gluons is one of the primary challenges in strong interaction physics. This interaction is governed by Quantum Chromodynamics (QCD), which is a theory for understanding the dynamics of strong. QCD displays the asymptotic freedom of hadrons at very short distances and also the confinement of quarks and gluons inside hadrons. However, solutions of this QCD theory in the non-perturbative domain of the interaction are extremely difficult to achieve, mainly because confinement happens on the hadronic scale on which the coupling constant is large and prevents any perturbative approach. Thus leaving us with strategies such as lattice QCD or formulating QCD sum rules to get around this problem. In exclusive hadron production the yN interaction is recognized for being a powerful method for investigating hadrons and the mysteries that still exist within the strong interaction. From reactions with the nucleon, the strong interaction can be investigated through the transition amplitudes to the N and Delta resonances. More specifically, if an electromagnetic interaction is well known then the intermediate resonance states may be evaluated through meson photoproduction. To gain more detailed insight into this interaction, we look to probe the baryon structure of the nucleon and the photo-excited resonance decays through photon scattering off a deuteron producing two pions in the final state. This photoproduction process off the deuteron will be used to investigate known baryon resonances in the two pion channel. The two pion final state will be investigated for unraveling new information into the photo-coupling strengths. We want to explore final state interactions, search for properties of known resonances, and to explore the possibility of seeing missing states that are predicted by quark models but have not yet been found experimentally. Using the CEBAF Large Acceptance Spectrometer (CLAS), the hadronic products are detected in coincidence with the incident scattered photon on a deuterium target. This makes it possible to measure the single differential cross sections and the decay angular distributions for the production of two pion final states. The measured cross sections will contribute significantly to a better understanding of the coupling strengths that govern the baryonic and mesonic resonances which will push the knowledge of the strong interaction to a next level. We use CLAS to study the two pion channel from the eg3 data set, for resonance production, specifically investigating the exclusive reaction of yd --> p pi^+pi^?n, and comparing the relevant cross sections to already existing data sets. The eg3 data set provided an excellent data set for investigating photo-induced baryonic and mesonic resonances. It contains a large photon tagging range from 1.1 to 5.5 GeV in the study of photo-coupling strengths, as well as an available two pion reaction channel for resonant decay study. These measurements provide unique and coherent results from tagged photons over a broad range of energy, and represent the only two pion production data above 5 GeV at this present time. We found that the data produced good comparable single-differentials cross sections to other existing CLAS (gll dataset) two pion differential cross sections, and an excellent comparable total cross section to published (ELSA and ABBHHM) two pion total cross sections.

Graham, Lewis P. [South Carolina U.

2012-12-01T23:59:59.000Z

170

UCLA Intermediate Energy Nuclear and Particle Physics Research: Final Report  

SciTech Connect (OSTI)

This project covers the following research: (a) Investigations into the structure of the proton and neutron. This is done by investigating the different resonance states of nucleons with beams of tagged, polarized photons, linearly as well as circularly, incident on polarized hydrogen/deuterium targets and measuring the production of {pi}{sup #25;0}, 2{pi}{sup #25;}0, 3{pi}{sup #25;0}, {eta}#17;, {eta}', {omega}, etc. The principal detector is the Crystal Ball multiphoton spectrometer which has an acceptance of nearly 4#25;. It has been moved to the MAMI accelerator facility of the University of Mainz, Germany. We investigate the conversion of electromagnetic energy into mesonic matter and conversely. (b) We investigate the consequences of applying the "standard" symmetries of isospin, Gâ??parity, charge conjugation, C, P, T, and chirality using rare and forbidden decays of light mesons such as the {eta}#17;,{eta}' and {omega}. We also investigate the consequences of these symmetries being slightly broken symmetries. We do this by studying selected meson decays using the Crystal Ball detector. (c) We determine the mass, or more precisely the mass difference of the three light quarks (which are inputs to Quantum Chromodynamics) by measuring the decay rate of specially selected {eta}#17; and {eta}' decay modes, again we use the Crystal Ball. (d)We have started a new program to search for the 33 missing cascade baryons using the CLAS detector at the Thomas Jefferson Laboratory. Cascade resonances are very special: they have double strangeness and are quite narrow. This implies that they can be discovered by the missing mass technique in photoproduction reactions such as in {gamma}p{yields}{Xi}{sup #4;â??}K{sup +}K{sup +}. The cascade program is of particular importance for the upgrade to 12 GeV of the CLAS detector and for design of the Hall D at JLab. (e) Finally, we are getting more involved in a new program to measure the hadronic matter form factor of complex nuclei, in particular the "neutron skin" of {sup 208}Pb, which is of great interest to astroparticle physics for determining the properties of neutron stars. Processes of study are coherent and nonâ??coherent #25;0 photoproduction. The Crystal Ball is uniquely suited for these studies because of the large acceptance, good direction and energy resolution and it is an inclusive detector for the #25;{pi}{sup 0} final state and exclusive for background such as 2#25;{pi}{sup 0}.

B.M.K. Nefkens (Principal Investigator, ed.); J. Goetz; A. Lapik; M. Korolija; S. Prakhov; A. Starostin (ed.)

2011-05-18T23:59:59.000Z

171

First measurement of target and double spin asymmetries for polarized e- polarized p --> e p pi0 in the nucleon resonance region above the Delta(1232)  

SciTech Connect (OSTI)

DOI: http://dx.doi.org/10.1103/PhysRevC.78.045204
The exclusive channel polarized proton(polarized e,e prime p)pi0 was studied in the first and second nucleon resonance regions in the Q2 range from 0.187 to 0.770 GeV2 at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS). Longitudinal target and beam-target asymmetries were extracted over a large range of center-of-mass angles of the pi0 and compared to the unitary isobar model MAID, the dynamic model by Sato and Lee, and the dynamic model DMT. A strong sensitivity to individual models was observed, in particular for the target asymmetry and in the higher invariant mass region. This data set, once included in the global fits of the above models, is expected to place strong constraints on the electrocoupling amplitudes A_{1/2} and S_{1/2} for the Roper resonance N(1400)P11, and the N(1535)S11 and N(1520)D13 states.

Biselli, Angela; Burkert, Volker; Amaryan, Moscov; Amaryan, Moskov; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bedlinskiy, Ivan; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Blaszczyk, Lukasz; Bookwalter, Craig; Boyarinov, Sergey; Bosted, Peter; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crede, Volker; Dale, Daniel; Dashyan, Natalya; De Masi, Rita; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Deur, Alexandre; Dhamija, Seema; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Doughty, David; Dugger, Michael; Dzyubak, Oleksandr; Egiyan, Hovanes; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feuerbach, Robert; Fersch, Robert; Forest, Tony; Fradi, Ahmed; Garcon, Michel; Gavalian, Gagik; Gevorgyan, Nerses; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gohn, Wesley; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Hassall, Neil; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Keller, Dustin; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Kossov, Mikhail; Krahn, Zebulun; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Kuznetsov, Viacheslav; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Mirazita, Marco; Mokeev, Viktor; Moreno, Brahim; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kil; Park, Seungkyung; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schott, Diane; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Weygand, Dennis; Williams, M.; Wolin, Elliott; Wood, Michael; Yegneswaran, Amrit; Yurov, Mikhail; Zana, Lorenzo; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen

2008-10-01T23:59:59.000Z

172

Induced polarization of ?(1116) in kaon electroproduction  

E-Print Network [OSTI]

We have measured the induced polarization of the ${\\Lambda}(1116)$ in the reaction $ep\\rightarrow e'K^+{\\Lambda}$, detecting the scattered $e'$ and $K^+$ in the final state along with the proton from the decay $\\Lambda\\rightarrow p\\pi^-$.The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy $W$ ($1.6\\leq W \\leq 2.7$ GeV) and covered the full range of the kaon production angle at an average momentum transfer $Q^2=1.90$ GeV$^2$.In this experiment a 5.50 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the $W$ and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially $Q^2$ independent in our kinematic domain, suggesting that somewhere below the $Q^2$ covered here there must be a strong $Q^2$ dependence. Along with previously published photo- and electroproduction cross sections and polarization observables, these data are needed for the development of models, such as effective field theories, and as input to coupled-channel analyses that can provide evidence of previously unobserved $s$-channel resonances.

M. Gabrielyan; B. A. Raue; D. S. Carman; K. Park; K. P. Adhikari; D. Adikaram; M. J. Amaryan; S. Anefalos Pereira; H. Avakian; J. Ball; N. A. Baltzell; M. Battaglieri; V. Baturin; I. Bedlinskiy; A. S. Biselli; J. Bono; S. Boiarinov; W. J. Briscoe; W. K. Brooks; V. D. Burkert; T. Cao; A. Celentano; S. Chandavar; G. Charles; P. L. Cole; M. Contalbrigo; O. Cortes; V. Crede; A. DAngelo; N. Dashyan; R. De Vita; E. De Sanctis; A. Deur; C. Djalali; D. Doughty; R. Dupre; L. El Fassi; P. Eugenio; G. Fedotov; S. Fegan; J. A. Fleming; T. A. Forest; B. Garillon; N. Gevorgyan; Y. Ghandilyan; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; J. T. Goetz; E. Golovatch; R. W. Gothe; K. A. Griffioen; M. Guidal; L. Guo; K. Hafidi; H. Hakobyan; M. Hattawy; K. Hicks; D. Ho; M. Holtrop; S. M. Hughes; Y. Ilieva; D. G. Ireland; B. S. Ishkhanov; D. Jenkins; H. Jiang; H. S. Jo; K. Joo; D. Keller; M. Khandaker; W. Kim; F. J. Klein; S. Koirala; V. Kubarovsky; S. E. Kuhn; S. V. Kuleshov; P. Lenisa; W. I. Levine; K. Livingston; I. J. D. MacGregor; M. Mayer; B. McKinnon; C. A. Meyer; M. D. Mestayer; M. Mirazita; V. Mokeev; C. I. Moody; H. Moutarde; A Movsisyan; E. Munevar; C. Munoz Camacho; P. Nadel-Turonski; S. Niccolai; G. Niculescu; M. Osipenko; L. L. Pappalardo; R. Paremuzyan; E. Pasyuk; P. Peng; W. Phelps; J. J. Phillips; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; D. Protopopescu; D. Rimal; M. Ripani; A. Rizzo; F. Sabatie; C. Salgado; D. Schott; R. A. Schumacher; A. Simonyan; G. D. Smith; D. I. Sober; D. Sokhan; S. S. Stepanyan; S. Stepanyan; I. I. Strakovsky; S. Strauch; V. Sytnik; W. Tang; M. Ungaro; A. V. Vlassov; H. Voskanyan; E. Voutier; N. K. Walford; D. P. Watts; X. Wei; L. B. Weinstein; N. Zachariou; L. Zana; J. Zhang

2014-06-16T23:59:59.000Z

173

Differential cross sections for gamma + p --> K^+ + Y for Lambda and Sigma^0 hyperons  

SciTech Connect (OSTI)

High-statistics cross sections for the reactions {gamma} + p {yields} K{sup +} + {Lambda} and {gamma} + p {yields} K{sup +} + {Sigma}{sup 0} have been measured using CLAS at Jefferson Lab for center-of-mass energies W between 1.6 and 2.53 GeV, and for -0.85 < cos {theta}{sub K{sup +}}{sup c.m.} < +0.95. In the K{sup +}{Lambda} channel we confirm a resonance-like structure near W=1.9 GeV at backward kaon angles. The position and width of this structure change with angle, indicating that more than one resonance is likely playing a role. The K{sup +} {Lambda} channel at forward angles and all energies is well described by a t-channel scaling characteristic of Regge exchange, while the same scaling applied to the K{sup +} {Sigma}{sup 0} channel is less successful. Several existing theoretical models are compared to the data, but none provide a good representation of the results.

R. Bradford; R.A. Schumacher; J.W.C. McNabb; L. Todor; et. Al.

2005-09-29T23:59:59.000Z

174

Measurement of unpolarized semi-inclusive pi+ electroproduction off the proton  

SciTech Connect (OSTI)

Semi-inclusive pi+ electroproduction on protons has been measured with the CLAS detector at Jefferson Lab. The measurement was performed on a liquid-hydrogen target using a 5.75 GeV electron beam. The complete five-fold differential cross sections were measured over a wide kinematic range in Q2, x, z, and pT and over the complete range of azimuthal angles, phi, enabling us to separate the different structure functions, H2+eps*H1, H3 and H4. Our measurements of H2 at low-x were found to be in fairly good agreement with pQCD calculations, suggesting a precocious factorization of the process. Indeed, the conventional f(x)*D(z) term can account for almost all of the observed cross section, even at small z. The measured xF-distributions are in qualitative agreement with high energy data, which suggests a surprising numerical similarity between the spectator diquark fragmentation in the present reaction and the anti-quark fragmentation measured in e+e- collisions. We have observed that the p

Osipenko, Mikhail; Ripani, Marco; Ricco, Giovanni; Avagyan, Harutyun; De Vita, Raffaella; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Audit, Gerard; Bagdasaryan, H.; Baillie, Nathan; Ball, J.P.; Ball, Jacques; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bonner, Billy; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, Wilbert; Brooks, William; Bultmann, S.; Bueltmann, Stephen; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Cazes, Antoine; Ceccopieri, Federico; Chen, Shifeng; Cole, Philip; Collins, Patrick; Coltharp, Philip; Corvisiero, Pietro; Crabb, Donald; Crede, Volker; Cummings, John; Dashyan, Natalya; De Masi, Rita; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dharmawardane, Kahanawita; Dhuga, Kalvir; Dickson, Richard; Djalali, Chaden; Dodge, Gail; Donnelly, J.; Doughty, David; Drozdov, V.; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fatemi, Renee; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Golovach, Evgeny; Gonenc, Atilla; Gordon, Christopher; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guillo, Matthieu; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Heddle, David; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ilyichev, Alexander; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Marchand, Claude; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McCracken, Michael; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Morand, Ludyvine; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Napolitano, James; Nasseripour, Rakhsha; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; O'Rielly, Grant; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Philips, Sasha; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Polli, Ermanno; Popa, Iulian; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Qin, Liming; Raue, Brian; Riccardi, Gregory; Ritchie, Barry; Rosner, Guenther; Rossi, Patrizia; Rubin, Philip; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Shvedunov, Nikolay; Skabelin, Alexander; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinskiy, Aleksey; Stepanyan, Samuel; Stepanyan, Stepan; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Thoma, Ulrike; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Trentadue, L.; Tur, Clarisse; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Weygand, Dennis; Williams,

2008-01-01T23:59:59.000Z

175

First Measurement of Beam-Recoil Observables Cx and Cz  

SciTech Connect (OSTI)

Spin transfer from circularly polarized real photons to recoiling hyperons has been measured for the reactions $\\vec\\gamma + p \\to K^+ + \\vec\\Lambda$ and $\\vec\\gamma + p \\to K^+ + \\vec\\Sigma^0$. The data were obtained using the CLAS detector at Jefferson Lab for center-of-mass energies $W$ between 1.6 and 2.53 GeV, and for $-0.85<\\cos\\theta_{K^+}^{c.m.}< +0.95$. For the $\\Lambda$, the polarization transfer coefficient along the photon momentum axis, $C_z$, was found to be near unity for a wide range of energy and kaon production angles. The associated transverse polarization coefficient, $C_x$, is smaller than $C_z$ by a roughly constant difference of unity. Most significantly, the {\\it total} $\\Lambda$ polarization vector, including the induced polarization $P$, has magnitude consistent with unity at all measured energies and production angles when the beam is fully polarized. For the $\\Sigma^0$ this simple phenomenology does not hold. All existing hadrodynamic models are in poor agreement with these results.

R. Bradford; R.A. Schumacher; G. Adams; M.J. Amaryan; P. Ambrozewicz; E. Anciant; M. Anghinolfi; B. Asavapibhop; G. Asryan; G. Audit; H. Avakian; H. Bagdasaryan; N. Baillie; J.P. Ball; N.A. Baltzell; S. Barrow; V. Batourine; M. Battaglieri; K. Beard; I. Bedlinskiy; M. Bektasoglu; M. Bellis; N. Benmouna; B.L. Berman; N. Bianchi; A.S. Biselli; B.E. Bonner; S. Bouchigny; S. Boiarinov; D. Branford; W.J. Briscoe; W.K. Brooks; S. Bultmann; V.D. Burkert; C. Butuceanu; J.R. Calarco; S.L. Careccia; D.S. Carman; B. Carnahan; S. Chen; P.L. Cole; A. Coleman; P. Collins; P. Coltharp; D. Cords; P. Corvisiero; D. Crabb; H. Crannell; V. Crede; J.P. Cummings; R. De Masi; E. De Sanctis; R. De Vita; P.V. Degtyarenko; H. Denizli; L. Dennis; A. Deur; K.V. Dharmawardane; R. Dickson; C. Djalali; G.E. Dodge; J. Donnelly; D. Doughty; P. Dragovitsch; M. Dugger; S. Dytman; O.P. Dzyubak; H. Egiyan; ; K.S. Egiyan; L. El Fassi; L. Elouadrhiri; A. Empl; P. Eugenio; R. Fatemi; G. Fedotov; G. Feldman; R.J. Feuerbach; T.A. Forest; H. Funsten; M. Garcon; G. Gavalian; ; G.P. Gilfoyle; K.L. Giovanetti; F.X. Girod; J.T. Goetz; A. Gonenc; R.W. Gothe; K.A. Griffioen; M. Guidal; M. Guillo; N. Guler; L. Guo; V. Gyurjyan; C. Hadjidakis; K. Hafidi; H. Hakobyan; R.S. Hakobyan; J. Hardie; D. Heddle; F.W. Hersman; K. Hicks; I. Hleiqawi; M. Holtrop; J. Hu; M. Huertas; C.E. Hyde-Wright; Y. Ilieva; D.G. Ireland; B.S. Ishkhanov; E.L. Isupov; M.M. Ito; D. Jenkins; H.S. Jo; K. Joo; H.G. Juengst; N. Kalantarians; J.D. Kellie; M. Khandaker; K.Y. Kim; K. Kim; W. Kim; A. Klein; F.J. Klein; M. Klusman; M. Kossov; L.H. Kramer; V. Kubarovsky; J. Kuhn; S.E. Kuhn; S.V. Kuleshov; J. Lachniet; J.M. Laget; J. Langheinrich; D. Lawrence; A.C.S. Lima; K. Livingston; H.Y. Lu; K. Lukashin; M. MacCormick; J.J. Manak; C. Marchand; N. Markov; S. McAleer; B. McKinnon; J.W.C. McNabb; B.A. Mecking; M.D. Mestayer; C.A. Meyer; T. Mibe; K. Mikhailov; M. Mirazita; R. Miskimen; V. Mokeev; K. Moriya; S.A. Morrow; M. Moteabbed; V. Muccifora; J. Mueller; G.S. Mutchler; P. Nadel-Turonski; J. Napolitano; R. Nasseripour; N. Natasha; S. Niccolai; G. Niculescu; I. Niculescu; B.B. Niczyporuk; M.R. Niroula; R.A. Niyazov; M. Nozar; G.V. ORielly; M. Osipenko; A.I. Ostrovidov; K. Park; E. Pasyuk; C. Paterson; S.A. Philips; J. Pierce; N. Pivnyuk; D. Pocanic; O. Pogorelko; E. Polli; I. Popa; S. Pozdniakov; B.M. Preedom; J.W. Price; Y. Prok; D. Protopopescu; L.M. Qin; B.P. Quinn; B.A. Raue; G. Riccardi; G. Ricco; M. Ripani; B.G. Ritchie; F. Ronchetti; G. Rosner; P. Rossi; D. Rowntree; P.D. Rubin; F. Sabatie; J. Salamanca; C. Salgado; J.P. Santoro; ; V. Sapunenko; V.S. Serov; A. Shafi; Y.G. Sharabian; J. Shaw; N.V. Shvedunov; S. Simionatto; A.V. Skabelin; E.S. Smith; L.C. Smith; D.I. Sober; D. Sokhan; M. Spraker; A. Stavinsky; S.S. Stepanyan; S. Stepanyan; B.E. Stokes; P. Stoler; I.I. Strakovsky; S. Strauch; M. Taiuti; S. Taylor; D.J. Tedeschi; U. Thoma; R. Thompson; A. Tkabladze; S. Tkachenko; L. Todor; C. Tur; M. Ungaro; M.F. Vineyard; A.V. Vlassov; K. Wang; D.P. Watts; L.B. Weinstein; H. Weller; D.P. Weygand; M. Williams; E. Wolin; M.H. Wood; A. Yegneswaran; J. Yun; L. Zana; J. Zhang; B. Zhao; and Z.W. Zhao

2007-03-01T23:59:59.000Z

176

Search for the photo-excitation of exotic mesons in the pi+pi+pi- system  

E-Print Network [OSTI]

A search for exotic mesons in the $\\pi^{+}\\pi^{+}\\pi^{-}$ system photoproduced by the charge exchange reaction $\\gamma p\\to \\pi^{+}\\pi^{+}\\pi^{-}(n)$ was carried out by the CLAS collaboration at Jefferson Lab. A tagged-photon beam with energies in the 4.8 to 5.4 GeV range, produced through bremsstrahlung from a 5.744 GeV electron beam, was incident on a liquid-hydrogen target. A Partial Wave Analysis (PWA) was performed on a sample of 83,000 events, the highest such statistics to date in this reaction at these energies. The main objective of this study was to look for the photoproduction of an exotic $J^{PC} = 1^{-+}$ resonant state in the 1 to 2 GeV mass range. Our PWA analysis, based on the isobar model, shows production of the $a_{2}(1320)$ and the $\\pi_{2}(1670)$ mesons, but no evidence for the $a_{1}(1260)$, nor the $\\pi_{1}(1600)$ exotic state at the expected levels. An upper limit of 13.5 nb is determined for the exotic $\\pi_1(1600)$ cross section, less than 2% of the $a_2(1320)$ production.

M. Nozar; C. Salgado; D. P. Weygand; L. Guo; the CLAS Collaboration

2008-05-28T23:59:59.000Z

177

Measurement of the generalized form factors near threshold via ?*p ? n?+ at high Q2  

SciTech Connect (OSTI)

We report the first extraction of the pion-nucleon multipoles near the production threshold for the n?+ channel at relatively high momentum transfer (Q2 up to 4.2 GeV2). The dominance of the s-wave transverse multipole (E0+), expected in this region, allowed us to access the generalized form factor G1 within the light-cone sum rule (LCSR) framework as well as the axial form factor GA. The data analyzed in this work were collected by the nearly 4? CEBAF Large Acceptance Spectrometer (CLAS) using a 5.754-GeV electron beam on a proton target. The differential cross section and the ?-N multipole E0+/GD were measured using two different methods, the LCSR and a direct multipole fit. The results from the two methods are found to be consistent and almost Q2 independent.

Park, K; Adhikari, K P; Adikaram, D; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Batourine, V; Bedlinskiy, I; Bennett, R P; Biselli, A S; Bookwalter, C; Boiarinov, S; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Cole, P L; Contalbrigo, M; Crede, V; D'Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Doughty, D; Dupre, R; El Alaoui, A; El Fassi, L; Euginio, P; Fedotov, G; Fradi, A; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Girod, F X; Goetz, J T; Gohn, W; Golovatch, E; Graham, L; Griffioen, K A; Guidal, M; Guo, L; Hafidi, K; Hakobyan, H; Hanretty, C; Heddle, D; Hicks, K; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jenkins, D; Jo, H S; Joo, K; Khandaker, M; Khertarpal, P; Kim, A; Kim, W; Klein, F J; Kubarovsky, A; Kubarovsky, V; Kuhn, S E; Kuleshov, S V; Kvaltine, N D; Livingston, K; Lu, H Y; MacGregor, J D; Markov, N; Mayer, M; McKinnon, B; Mestayer, M D; Meyer, C A; Mineeva, T; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Park, S; Anefalos Pereira, S; Phelps, E; Pisano, S; Pogorelko, O; Pozdniakov, S; Price, J W; Procureur, S; Prok, Y; Ricco, G; Rimal, D; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabati ee, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Stoler, P; Strakovsky, I I; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tian, Y; Tkachenko, S; Trivedi, A; Ungaro, M; Vernarsky, B; Vlassov, A V; Voutier, E; Watts, D P; Weygand, D P; Wood, M H; Zachariou, N; Zhao, B; Zhao, Z W

2012-03-26T23:59:59.000Z

178

Study of few-nucleon systems with the CEBAF large acceptance spectrometer  

SciTech Connect (OSTI)

The study of few-nucleon systems at intermediate energies is an important aspect of the nuclear-physics program carried out by the CLAS Collaboration at Jefferson Laboratory. Our investigations aim at understanding the nuclear dynamics at short distances, the transition from hadronic to partonic description of nuclei, and how nuclei can be described in the framework of Quantum Chromodynamics. Our data on photodisintegration of 3He and 4He at beam energies from 0.3 GeV to 1.5 GeV strongly favor theoretical calculations that include three-body mechanisms and indicate significant contributions of these mechanisms at large momentum transfer, especially in the range of photon energies from 0.6 GeV to 0.8 GeV. Our investigations of exclusive and inclusive electron scattering off nuclear targets have yielded the determination of the ratio of pp to pn correlated pairs in 3He and of the probabilities of short-range correlations in nuclei. We have studied the transition from hadronic to partonic dynamics in nuclear processes by searching for the onset of scaling of the invariant cross sections of photoinduced reactions on few-nucleon systems. Our data are consistent with scaling at momentum transfer as low as 1 (GeV/c)2

Yordanka Ilieva

2011-05-01T23:59:59.000Z

179

Measurement of cross sections of p(e,e'pi^+)n for near pion threshold and high-lying resonances at high Q^2  

SciTech Connect (OSTI)

During the last decade, remarkable experimental data have been collected in an extensive programs to study the excitation of nucleon resonance (N*) at Jefferson Laboratory through pion electroproduction using polarized electron beam and unpolarized proton target. The CEBAF Large Acceptance Spectrometer (CLAS) is well suited for the study of a broad range of kinematics in the invariant mass W and photon virtuality Q{sup 2} with nearly complete angular coverage for the hadronic decays. Electron scattering allows us to probe the effective degrees of freedom in excited nucleon states from meson-baryon to dressed quarks in terms of varying the distance scale. The study of nucleon structure allows us to understand these effective degrees of freedom. In this proceeding, I present preliminary cross sections for single pion production in mass range of high-lying resonances as well as near the pion threshold. Analysis of N{pi}{sup +} cross sections together with N{pi}{sup 0} and N {pi}{pi} exclusive electroproduction data, will allow us for the first time to determine electrocouplings of several high-lying excited proton states (W {ge} 1.6 GeV) at photon virtualities that correspond to the transition toward the dominance of quark degrees of freedom. I also present preliminary result on the E{sub 0+} multipole near pion threshold at 2.0 GeV{sup 2} {le} Q{sup 2} {le} 4.5 GeV{sup 2} using exclusive N{pi}{sup +} electroproduction data.

Kijun Park

2012-04-01T23:59:59.000Z

180

Delta Electroproduction in 12-C  

SciTech Connect (OSTI)

The Delta-nucleus potential is a crucial element in the understanding of the nuclear system. Previous electroexcitation measurements in the delta region reported a Q2 dependence of the delta mass indicating that this potential is dependent on the momentum of the delta. Such a dependence is not observed for protons and neutrons in the nuclear medium. This thesis presents the experimental study of the electroexcitation of the delta resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4(pie) acceptance detector CLAS that enables the detection of the full reaction final state. Inclusive, semi inclusive, and exclusive cross sections were measured with an incident electron beam energy of 1.162GeV over the Q2 range 0.175-0.475 (GeV/c)2. A Q2 dependence of the delta mass was only observed in the exclusive measurements indicating that the delta-nucleus potential is affected by the momentum of the delta.

Steven McLauchlan

2003-01-31T23:59:59.000Z

Note: This page contains sample records for the topic "type-of-sale clas sification" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Polarization Observables for K{sup +}{Lambda} and K{sup +}{Sigma}{sup 0} Photoproduction form Polarized Protons  

SciTech Connect (OSTI)

The search for undiscovered excited states of the nucleon continues to be a focus of experiments at Jefferson Lab. Recent LQCD calculations have confirmed long-standing quark-model predictions of many more states than have so far been identified. A large effort for the N* program has been launched using the CLAS detector to provide the database that will allow nearly model-independent partial wave analyses to be carried out in the search for such states. Polarization observables play a crucial role in this effort, as they are essential in disentangling overlapping resonant and non-resonant amplitudes. In 2010, double-polarization data were taken at JLab using circularly polarized photons incident on a transversely polarized frozen-spin butanol target. Our current analysis yields preliminary data of the T and F asymmetries of the K{sup +}{Lambda} and K{sup +}{Sigma}{sup 0} final states, which are compared to predictions of recent multipole analyses. This work is the first of its kind and will significantly broaden the world database for these reactions.

Walford, Natalie K. [Catholic University of America, Washington, DC (United States); Klein, Franz J.W. [Catholic University of America, Washington, DC (United States)

2014-01-01T23:59:59.000Z

182

Exclusive processes at JLab at 6 GeV  

SciTech Connect (OSTI)

Deeply virtual exclusive reactions provide a unique opportunity to probe the complex internal structure of the nucleon. They allow to access information about the correlations between parton transverse spatial and longitudinal momentum distributions from experimental observables. Dedicated experiments to study Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP) have been carried out at Jefferson Lab using continuous electron beam with energies up to 6 GeV. Unpolarized cross sections, beam, target and double spin asymmetries have been measured for DVCS as well as for ?0 exclusive electroproduction. The data from Hall B provide a wide kinematic coverage with Q2=1-4.5 GeV2, xB=0.1-0.5, and ?t up to 2 GeV2. Hall A data have limited kinematic range partially overlapping with Hall B kinematics but provide a high accuracy measurements. Scaling tests of the DVCS cross sections provide solid evidence of twist-2 dominance, which makes chiral-even GPDs accessible even at modest Q2. We will discuss the interpretation of these data in terms of Generalized Parton Distributions (GPDs) model. Successful description of the recent CLAS ?0 exclusive production data within the framework of the GPD-based model provides a unique opportunity to access the chiral-odd GPDs.

Kim, Andrey [University of Connecticut, JLAB

2015-01-01T23:59:59.000Z

183

Towards a Resolution of the Proton Form Factor Problem: New Electron and Positron Scattering Data  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

There is a significant discrepancy between the values of the proton electric form factor, GpE, extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of GpE from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (epsilon) and momentum transfer (Q2) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing ? at Q2=1.45 GeV2. This measurement is consistent with the size of the form factor discrepancy at Q2?1.75 GeV2 and with hadronic calculations including nucleon and Delta intermediate states, which have been shown to resolve the discrepancy up to 2-3 GeV2.

Adikaram, D.; Rimal, D.; Weinstein, L B.; Raue, B.; Khetarpal, P.; Bennett, R; Arrington, J.; Brooks, W; Adhikari, K; Afanasev, A; Amaryan, M; Anderson, M; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A; Bono, J.; Boiarinov, S.; Briscoe, W; Burkert, V; Carman, D; Careccia, S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P; Contalbrigo, M.; Crede, V.; D'Angelo, A; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dodge, G; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J; Fradi, A.; Garillon, B.; Gilfoyle, G; Giovanetti, K; Girod, F; Goetz, J; Gohn, W.; Golovatch, E.; Gothe, R; Griffioen, K; Guegan, B.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S; Hyde, C E; Ilieva, Y.; Ireland, D; Ishkhanov, B; Jenkins, D.; Jiang, H.; Jo, H; Joo, K.; Joosten, S.; Kalantarians, N.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F; Koirala, S.; Kubarovsky, V.; Kuhn, S; Livingston, K.; Lu, H; MacGregor, I; Markov, N.; Mattione, P.; Mayer, M.; McKinnon, B.; Mestayer, M; Meyer, C; Mirazita, M.; Mokeev, V.; Montgomery, R; Moody, C; Moutarde, H.; Movsisyan, A.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A; Park, K.; Pasyuk, E.; Pisano, S.; Pogorelko, O.; Price, J; Procureur, S.; Prok, Y.; Protopopescu, D.; Puckett, A; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabati, F; Salgado, C.; Schott, D.; Schumacher, R; Seder, E.; Sharabian, Y; Simonyan, A.; Skorodumina, I.; Smith, E; Smith, G; Sober, D; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Stoler, P.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Trivedi, A.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N; Watts, D; Wei, X.; Wood, M; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z; Zonta, I.

2015-02-10T23:59:59.000Z

184

Neutron observables from inclusive lepton scattering on nuclei  

SciTech Connect (OSTI)

We analyze new data from Thomas Jefferson National Accelerator Facility (JLab) for inclusive electron scattering on various targets. Computed and measured total inclusive cross sections in the range 0.3 < or approx. x < or approx. 0.95 show reasonable agreement on a logarithmic scale for all targets. However, closer inspection of the quasielastic components reveals serious discrepancies. European Muon Collaboration (EMC) ratios with conceivably smaller systematic errors fare the same. As a consequence, the new data do not enable the extraction of the magnetic form factor G{sub M}{sup n} and the structure function F{sub 2}{sup n} of the neutron, although the application of exactly the same analysis to older data had been successful. We incorporate in the above analysis older CLAS Collaboration data on F{sub 2}{sup 2H}. Removal of some scattered points from those makes it appear possible to obtain the desired neutron information. We compare our results with others from alternative sources. Special attention is paid to the A=3 isodoublet cross sections and EMC ratios. Present data exist only for {sup 3}He, but the available input in combination with charge symmetry enables computations for {sup 3}H. Their average is the computed isoscalar part and is compared with the empirical modification of {sup 3}He EMC ratios toward a fictitious A=3 isosinglet.

Rinat, A. S.; Taragin, M. F. [Weizmann Institute of Science, Department of Particle Physics, Rehovot 76100 (Israel)

2010-07-15T23:59:59.000Z

185

Measurement of the Nucleon Structure Function F2 in the Nuclear Medium and Evaluation of its Moments  

SciTech Connect (OSTI)

We report on the measurement of inclusive electron scattering off a carbon target performed with CLAS at Jefferson Laboratory. A combination of three different beam energies 1.161, 2.261 and 4.461 GeV allowed us to reach an invariant mass of the final-state hadronic system W~2.4 GeV with four-momentum transfers Q2 ranging from 0.2 to 5 GeV2. These data, together with previous measurements of the inclusive electron scattering off proton and deuteron, which cover a similar continuous two-dimensional region of Q2 and Bjorken variable x, permit the study of nuclear modifications of the nucleon structure. By using these, as well as other world data, we evaluated the F2 structure function and its moments. Using an OPE-based twist expansion, we studied the Q2-evolution of the moments, obtaining a separation of the leading-twist and the total higher-twist terms. The carbon-to-deuteron ratio of the leading-twist contributions to the F2 moments exhibits the well known EMC effect, compatible with that discovered previously in x-space. The total higher-twist term in the carbon nucleus appears, although with large systematic uncertainites, to be smaller with respect to the deuteron case for n<7, suggesting partial parton deconfinement in nuclear matter. We speculate that the spatial extension of the nucleon is changed when it is immersed in the nuclear medium.

M. Osipenko

2010-11-01T23:59:59.000Z

186

Induced polarization of Lambda(1116) in kaon electroproduction  

SciTech Connect (OSTI)

We have measured the induced polarization of the ?(1116) in the reaction ep?e?K+?, detecting the scattered e? and K+ in the final state along with the proton from the decay ??p??.The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy W (1.6?W?2.7 GeV) and covered the full range of the kaon production angle at an average momentum transfer Q2=1.90 GeV2.In this experiment a 5.50 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the W and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially Q2 independent in our kinematic domain, suggesting that somewhere below the Q2 covered here there must be a strong Q2 dependence. Along with previously published photo- and electroproduction cross sections and polarization observables, these data are needed for the development of models, such as effective field theories, and as input to coupled-channel analyses that can provide evidence of previously unobserved s-channel resonances.

Gabrielyan, M.; Raue, B.A.; Carman, D.S.; Park, K.; Adhikari, K.P.; Adikaram, D.; Amaryan, M.J.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N.A.; Battaglieri, M.; Baturin, V.; Bedlinskiy, I.; Biselli, A.S.; Bono, J.; Boiarinov, S.; Briscoe, W.J.; Brooks, W.K.; Burkert, V.D.; Cao, T.; Celentano, A.; Chandavar, S.; Charles, G.; Cole, P.L.; Contalbrigo, M.; Cortes, O.; Crede, V.; DAngelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; ElFassi, L.; Eugenio, P.; Fedotov, G.; Fegan, S.; Fleming, J.A.; Forest, T.A.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G.P.; Giovanetti, K.L.; Girod, F.X.; Goetz, J.T.; Golovatch, E.; Gothe, R.W.; Griffioen, K.A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hattawy, M.; Hicks, K.; Ho, D.; Holtrop, M.; Hughes, S.M.; Ilieva, Y.; Ireland, D.G.; Ishkhanov, B.S.; Jenkins, D.; Jiang, H.; Jo, H.S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, W.; Klein, F.J.; Koirala, S.; Kubarovsky, V.; Kuhn, S.E.; Kuleshov, S.V.; Lenisa, P.; Levine, W.I.; Livingston, K.; MacGregor, I.J.D.; Mayer, M.; McKinnon, B.; Meyer, C.A.; Mestayer, M.D.; Mirazita, M.; Mokeev, V.; Moody, C.I.; Moutarde, H.; Movsisyan, A; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Pappalardo, L.L.; Paremuzyan, R.; Pasyuk, E.; Peng, P.; Phelps, W.; Phillips, J.J.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J.W.; Procureur, S.; Protopopescu, D.; Rimal, D.; Ripani, M.; Rizzo, A.; Sabatie, F.; Salgado, C.; Schott, D.; Schumacher, R.A.; Simonyan, A.; Smith, G.D.; Sober, D.I.; Sokhan, D.; Stepanyan, S.S.; Stepanyan, S.; Strakovsky, I.I.; Strauch, S.; Sytnik, V.; Tang, W.; Ungaro, M.; Vlassov, A.V.; Voskanyan, H.; Voutier, E.; Walford, N.K.; Watts, D.P.; Wei, X.; Weinstein, L.B.; Zachariou, N.; Zana, L.; Zhang, J.

2014-09-01T23:59:59.000Z

187

Beam-spin Asymmetries from Semi-inclusive Pion Electroproduction  

SciTech Connect (OSTI)

We have measured the moment A{sup sin{phi}}{sub LU} corresponding to the polarized electron beam-spin asymmetry in SIDIS. A{sup sin{phi}}{sub LU} is a twist-3 quantity providing information about quark-gluon correlations. Data were taken with the CLAS Spectrometer at Jefferson Lab using a 5.498 GeV longitudinally polarized electron beam and an unpolarized liquid hydrogen target. All three pion channels (pi{sup +}, pi{sup 0} and pi{sup -}) were measured simultaneously over a large range of kinematics within the virtuality range Q{sup 2} ~ 1.0-4.5 GeV{sup 2}. The observable was measured with good statistical precision over a large range of z, P{sub T}, x{sub B}, and Q{sup 2}, which permits comparison with several reaction models. The discussed measurements provide an upgrade in statistics over previous measurements, and serve as the first evidence for the negative sign of the {pi}{sup -} sin{phi} Moment.

Gohn, Wesley P. [University of Connecticut, Storrs, CT (United States); Avakian, Harut A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Joo, Kyungseon [University of Connecticut, Storrs, CT (United States); Ungaro, Maurizio [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2014-04-01T23:59:59.000Z

188

Electron Scattering From High-Momentum Neutrons in Deuterium  

SciTech Connect (OSTI)

We report results from an experiment measuring the semi-inclusive reaction D(e,e'p{sub s}) where the proton p{sub s} is moving at a large angle relative to the momentum transfer. If we assume that the proton was a spectator to the reaction taking place on the neutron in deuterium, the initial state of that neutron can be inferred. This method, known as spectator tagging, can be used to study electron scattering from high-momentum (off-shell) neutrons in deuterium. The data were taken with a 5.765 GeV electron beam on a deuterium target in Jefferson Laboratory's Hall B, using the CLAS detector. A reduced cross section was extracted for different values of final-state missing mass W*, backward proton momentum {rvec p}{sub s} and momentum transfer Q{sup 2}. The data are compared to a simple PWIA spectator model. A strong enhancement in the data observed at transverse kinematics is not reproduced by the PWIA model. This enhancement can likely be associated with the contribution of final state interactions (FSI) that were not incorporated into the model. A ''bound neutron structure function'' F{sub 2n}{sup eff} was extracted as a function of W* and the scaling variable x* at extreme backward kinematics, where effects of FSI appear to be smaller. For p{sub s} > 400 MeV/c, where the neutron is far off-shell, the model overestimates the value of F{sub 2n}{sup eff} in the region of x* between 0.25 and 0.6. A modification of the bound neutron structure function is one of possible effects that can cause the observed deviation.

A.V. Klimenko; S.E. Kuhn

2005-10-12T23:59:59.000Z

189

Determination of the Azimuthal Asymmetry of Deuteron Photodisintegration in the Energy Region E{sub {gamma}} = 1.1 - 2.3 GeV  

SciTech Connect (OSTI)

Deuteron photodisintegration is a benchmark process for the investigation of the role of quarks and gluons in nuclei. Existing theoretical models of this process describe the available cross sections with the same degree of success. Therefore, spin-dependent observables are crucial for a better understanding of the underlying dynamical mechanisms. However, data on the induced polarization (P{sub y}), along with the polarization transfers (C{sub x'} and C{sub z'} ), have been shown to be insensitive to differences between theoretical models. On the other hand, the beam-spin asymmetry {Sigma} is predicted to have a large sensitivity and is expected to help in identifying the energy at which the transition from the hadronic to the quark-gluon picture of the deuteron takes place. Here, the work done to determine the experimental values of the beam-spin asymmetry in deuteron photodisintegration for photon energies between 1.1 ? 2.3 GeV is presented. The data were taken with the CLAS at the Thomas Jefferson National Accelerator Facility during the g13 experiment. Photons with linear polarization of ~80% were produced using the coherent bremsstrahlung facility in Hall B. The work done by the author to calibrate a specific detector system, select deuteron photodisintegration events, study the degree of photon polarization, and finally determine the azimuthal asymmetry and any systematic uncertainties associate with it, is comprehensively explained. This work shows that the collected data provide the kinematic coverage and statistics to test the available QCD-based models. The results of this study show that the available theoretical models in their current state do not adequately predict the azimuthal asymmetry in the energy region 1.1 ? 2.3 GeV.

Nicholas Zachariou

2012-05-20T23:59:59.000Z

190

Electron Scattering From High-Momentum Neutrons in Deuterium  

E-Print Network [OSTI]

We report results from an experiment measuring the semi-inclusive reaction $d(e,e'p_s)$ where the proton $p_s$ is moving at a large angle relative to the momentum transfer. If we assume that the proton was a spectator to the reaction taking place on the neutron in deuterium, the initial state of that neutron can be inferred. This method, known as spectator tagging, can be used to study electron scattering from high-momentum (off-shell) neutrons in deuterium. The data were taken with a 5.765 GeV electron beam on a deuterium target in Jefferson Laboratory's Hall B, using the CLAS detector. A reduced cross section was extracted for different values of final-state missing mass $W^{*}$, backward proton momentum $\\vec{p}_{s}$ and momentum transfer $Q^{2}$. The data are compared to a simple PWIA spectator model. A strong enhancement in the data observed at transverse kinematics is not reproduced by the PWIA model. This enhancement can likely be associated with the contribution of final state interactions (FSI) that were not incorporated into the model. A ``bound neutron structure function'' $F_{2n}^{eff}$ was extracted as a function of $W^{*}$ and the scaling variable $x^{*}$ at extreme backward kinematics, where effects of FSI appear to be smaller. For $p_{s}>400$ MeV/c, where the neutron is far off-shell, the model overestimates the value of $F_{2n}^{eff}$ in the region of $x^{*}$ between 0.25 and 0.6. A modification of the bound neutron structure function is one of possible effects that can cause the observed deviation.

A. V. Klimenko; S. E. Kuhn; for the CLAS collaboration

2005-10-12T23:59:59.000Z

191

Search for the Theta+ pentaquark in the reactions gammap-->[overline K]0K+n and gammap-->[overline K]0K0p  

SciTech Connect (OSTI)

The exclusive reactions {gamma}p {yields} {bar K}{sup 0} K{sup +} n and {gamma}p {yields} {bar K}{sup 0} K{sup 0} p have been studied in the photon energy range 1.6--3.8 GeV, searching for evidence of the exotic baryon {Theta}{sup +}(1540) in the decays {Theta}{sup +} {yields} nK{sup +} and {Theta}{sup +} {yields} pK{sup 0}. Data were collected with the CLAS detector at the Thomas Jefferson National Accelerator Facility. The integrated luminosity was about 70 pb{sup -1}. The reactions have been isolated by detecting the K{sup +} and proton directly, the neutral kaon via its decay to K{sub S} {yields} {pi}{sup +}{pi}{sup -} and the neutron or neutral kaon via the missing mass technique. The mass and width of known hyperons such as {Sigma}{sup +}, {Sigma}{sup -} and {Lambda}(1116) were used as a check of the mass determination accuracy and experimental resolution. Approximately 100,000 {Lambda}*(1520)'s and 150,000 {phi}'s were observed in the {bar K}{sup 0} K{sup +} n and {bar K}{sup 0} K{sup 0} p final state respectively. No evidence for the {Theta}{sup +} pentaquark was found in the nK{sup +} or pK{sub S} invariant mass spectra. Upper limits were set on the production cross section of the reaction {gamma}p {yields} {Theta}{sup +} {bar K}{sup 0} as functions of center-of-mass angle, nK{sup +} and pK{sub S} masses. Combining the results of the two reactions, the 95% C.L. upper limit on the total cross section for a resonance peaked at 1540 MeV was found to be 0.7 nb. Within most of the available theoretical models, this corresponds to an upper limit on the {Theta}{sup +} width, {Gamma}{sub {Theta}{sup +}}, ranging between 0.01 and 7 MeV.

Raffaella De Vita; Marco Battaglieri; V. Kubarovsky; Nathan Baltzell; Matthew Bellis; John Goett; Lei Guo; Gordon Mutchler; Paul Stoler; Maurizio Ungaro; Dennis Weygand; Moscov Amaryan; Pawel Ambrozewicz; Marco Anghinolfi; Gegham Asryan; Harutyun AVAKIAN; Harutyun Avakian; Hovhannes Baghdasaryan; Nathan Baillie; Jacques Ball; Vitaly Baturin; Ivan Bedlinski; Ivan Bedlinskiy; Nawal Benmouna; Barry Berman; Angela Biselli; Sergey Boyarinov; Sylvain Bouchigny; Robert Bradford; Derek Branford; William Briscoe; William Brooks; Stephen Bueltmann; Volker Burkert; Cornel Butuceanu; John Calarco; Sharon Careccia; Daniel Carman; Shifeng Chen; Eric Clinton; Philip Cole; Patrick Collins; Philip Coltharp; Donald Crabb; Hall Crannell; Volker Crede; John Cummings; D. Dale; Raffaella De Vita; Enzo De Sanctis; Pavel Degtiarenko; Alexandre Deur; Kahanawita Dharmawardane; Chaden Djalali; Gail Dodge; Joseph Donnelly; David Doughty; Michael Dugger; Oleksandr Dzyubak; Hovanes Egiyan; Kim Egiyan; Lamiaa Elfassi; Latifa Elouadrhiri; Paul Eugenio; Gleb Fedotov; Herbert Funsten; Marianna Gabrielyan; Liping Gan; Michel Garcon; Ashot Gasparian; Gagik Gavalian; Gerard Gilfoyle; Kevin Giovanetti; Francois-Xavier Girod; Oleksandr Glamazdin; John Goetz; Evgueni Golovatch; Atilla Gonenc; Christopher Gordon; Ralf Gothe; Keith Griffioen; Michel Guidal; Nevzat Guler; Harutyun Gyurjyan; Cynthia Hadjidakis; Kawtar Hafidi; Hayk Hakobyan; Rafael Hakobyan; John Hardie; F. Hersman; Kenneth Hicks; Ishaq Hleiqawi; Maurik Holtrop; Charles Hyde-Wright; Yordanka Ilieva; David Ireland; Boris Ishkhanov; Eugeny Isupov; Mark Ito; D. Jenkins; Hyon-Suk Jo; Kyungseon Joo; Henry Juengst; James Kellie; Mahbubul Khandaker; Wooyoung Kim; Andreas Klein; Franz Klein; Alexei Klimenko; Mikhail Kossov; Laird Kramer; Joachim Kuhn; Sebastian Kuhn; Sergey Kuleshov; Jeff Lachniet; Jean Laget; Jorn Langheinrich; Dave Lawrence; Tsung-shung Lee; Ji Li; K. Livingston; Haiyun Lu; Marion MacCormick; Nikolai Markov; Bryan McKinnon; Bernhard Mecking; Joseph Melone; Mac Mestayer; Curtis Meyer; Tsutomu Mibe; Konstantin Mikhaylov; Ralph Minehart; Marco Mirazita; R. Miskimen; Vasiliy Mochalov; Viktor Mokeev; Ludyvine Morand; Steven Morrow; Maryam Moteabbed; Pawel Nadel-Turonski; Itaru Nakagawa; Rakhsha Nasseripour; Silvia Niccolai; Gabriel Niculescu; Maria-Ioana Niculescu; Bogdan Niczyporuk; Megh Niroula; Rustam Niyazov; Mina Nozar; Mikhail Osipenko; Alexander Ostrovidov; Kijun Park; Evgueni Pasyuk; Craig Paterson; Joshua Pierce; Nikolay Pivnyuk; Dinko Pocanic; Oleg Pogorelko; Sergey Pozdnyakov; John Price; Yelena Prok; Dan Protopopescu; Brian Raue; Gregory Riccardi; Giovanni Ricco; Marco Ripani; Barry Ritchie; Federico Ronchetti; Guenther Rosner; Patrizia Rossi; Franck Sabatie; Carlos Salgado; Joseph Santoro; Vladimir Sapunenko; Reinhard Schumacher; Vladimir Serov; Youri Sharabian; Nikolay Shvedunov; Elton Smith; Lee Smith; Daniel Sober; Aleksey Stavinskiy; Samuel Stepanyan; Stepan Stepanyan; Burnham Stokes; Igor Strakovski; Steffen Strauch; Mauro Taiuti; David Tedeschi; Aram Teymurazyan; Ulrike Thoma; Avtandil Tkabladze; Svyatoslav Tkachenko; Luminita Todor; Clarisse Tur; Michael Vineyard; Alexander Vlassov; Daniel Watts; Lawrence Weinstein; M. Williams; Elliott Wolin; Michael Wood; Amrit Yegneswaran; Lorenzo Zana; Jixie Zhang; Bo Zhao; Zhiwen Zhao

2006-11-16T23:59:59.000Z

192

Short-Course Accelerated Radiotherapy in Palliative Treatment of Advanced Pelvic Malignancies: A Phase I Study  

SciTech Connect (OSTI)

Purpose: To define the maximum tolerated dose of a conformal short-course accelerated radiotherapy in patients with symptomatic advanced pelvic cancer. Methods and Materials: A phase I trial in 3 dose-escalation steps was designed: 14 Gy (3.5-Gy fractions), 16 Gy (4-Gy fractions), and 18 Gy (4.5-Gy fractions). The eligibility criteria included locally advanced and/or metastatic pelvic cancer and Eastern Cooperative Oncology Group performance status of {<=}3. Treatment was delivered in 2 days with twice-daily fractionation and at least an 8-hour interval. Patients were treated in cohorts of 6-12 to define the maximum tolerated dose. The dose-limiting toxicity was defined as any acute toxicity of grade 3 or greater, using the Radiation Therapy Oncology Group scale. Pain was recorded using a visual analog scale. The effect on quality of life was evaluated according to Cancer Linear Analog Scale (CLAS). Results: Of the 27 enrolled patients, 11 were male and 16 were female, with a median age of 72 years (range 47-86). The primary tumor sites were gynecologic (48%), colorectal (33.5%), and genitourinary (18.5%). The most frequent baseline symptoms were bleeding (48%) and pain (33%). Only grade 1-2 acute toxicities were recorded. No patients experienced dose-limiting toxicity. With a median follow-up time of 6 months (range 3-28), no late toxicities were observed. The overall (complete plus partial) symptom remission was 88.9% (95% confidence interval 66.0%-97.8%). Five patients (41.7%) had complete pain relief, and six (50%) showed >30% visual analog scale reduction. The overall response rate for pain was 91.67% (95% confidence interval 52.4%-99.9%). Conclusions: Conformal short course radiotherapy in twice-daily fractions for 2 consecutive days was well tolerated up to a total dose of 18 Gy. A phase II study is ongoing to confirm the efficacy on symptom control and quality of life indexes.

Caravatta, Luciana [Department of Radiation Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy)] [Department of Radiation Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Padula, Gilbert D.A. [Department of Radiation Oncology, Lacks Cancer Center Saint Mary's Health Care, Grand Rapids, MI (United States)] [Department of Radiation Oncology, Lacks Cancer Center Saint Mary's Health Care, Grand Rapids, MI (United States); Macchia, Gabriella, E-mail: gmacchia@rm.unicatt.it [Department of Radiation Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy)] [Department of Radiation Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Ferrandina, Gabriella [Department of Gynecologic Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy)] [Department of Gynecologic Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Bonomo, Pierluigi; Deodato, Francesco; Massaccesi, Mariangela [Department of Radiation Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy)] [Department of Radiation Oncology, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Mignogna, Samantha; Tambaro, Rosa [Department of Palliative Therapies, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy)] [Department of Palliative Therapies, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Rossi, Marco [Department of Anaesthesia, Intensive Care, and Pain Medicine, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy)] [Department of Anaesthesia, Intensive Care, and Pain Medicine, Fondazione di Ricercae Cura 'Giovanni Paolo II,' Universita Cattolica del S. Cuore, Campobasso (Italy); Flocco, Mariano ['Madre Teresa di Calcutta' Hospice, Larino (Italy)] ['Madre Teresa di Calcutta' Hospice, Larino (Italy); Scapati, Andrea [Department of Radiation Oncology, 'San Francesco' Hospital, Nuoro (Italy)] [Department of Radiation Oncology, 'San Francesco' Hospital, Nuoro (Italy); and others

2012-08-01T23:59:59.000Z

193

Demonstration of a novel technique to measure two-photon exchange effects in elastic ep scattering  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have significant model dependence, and there is limited direct experimental evidence for such corrections. The TPE contributions depend on the sign of the lepton charge in ep scattering, but the luminosities of secondary positron beams limited past measurement at large scattering angles, where the TPE effects are believe to be most significant. We present the results of a new experimental technique for making direct ep comparisons, which has the potential to make precise measurements over a broad range in Q2 and scattering angles. We use the Jefferson Laboratory electron beam and the Hall B photon tagger to generate a clean but untagged photon beam. The photon beam impinges on a converter foil to generate a mixed beam of electrons, positrons, and photons. A chicane is used to separate and recombine the electron and positron beams while the photon beam is stopped by a photon blocker. This provides a combined electron and positron beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen target. The large acceptance CLAS detector is used to identify and reconstruct elastic scattering events, determining both the initial lepton energy and the sign of the scattered lepton. The data were collected in two days with a primary electron beam energy of only 3.3 GeV, limiting the data from this run to smaller values of Q2 and scattering angle. Nonetheless, this measurement yields a data sample for ep with statistics comparable to those of the best previous measurements. We have shown that we can cleanly identify elastic scattering events and correct for the difference in acceptance for electron and positron scattering. Because we ran with only one polarity for the chicane, we are unable to study the difference between the incoming electron and positron beams. This systematic effect leads to the largest uncertainty in the final ratio of positron to electron scattering: R=1.0270.0050.05 for 2 >=0.206 GeV2 and 0.830 ? ? ? 0.943. We have demonstrated that the tertiary e beam generated using this technique provides the opportunity for dramatically improved comparisons of ep scattering, covering a significant range in both Q2 and scattering angle. Combining data with different chicane polarities will allow for detailed studies of the difference between the incoming e+ and e- beams.

Moteabbed, Maryam [Florida Institute of Technology; Niroula, Megh [Old Dominion University; Raue, Brian [Florida International University; Weinstein, Lawrence [Old Dominion University

2013-08-01T23:59:59.000Z

194

Demonstration of a novel technique to measure two-photon exchange effects in elastic ep scattering  

SciTech Connect (OSTI)

The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have significant model dependence, and there is limited direct experimental evidence for such corrections. The TPE contributions depend on the sign of the lepton charge in ep scattering, but the luminosities of secondary positron beams limited past measurement at large scattering angles, where the TPE effects are believe to be most significant. We present the results of a new experimental technique for making direct ep comparisons, which has the potential to make precise measurements over a broad range in Q2 and scattering angles. We use the Jefferson Laboratory electron beam and the Hall B photon tagger to generate a clean but untagged photon beam. The photon beam impinges on a converter foil to generate a mixed beam of electrons, positrons, and photons. A chicane is used to separate and recombine the electron and positron beams while the photon beam is stopped by a photon blocker. This provides a combined electron and positron beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen target. The large acceptance CLAS detector is used to identify and reconstruct elastic scattering events, determining both the initial lepton energy and the sign of the scattered lepton. The data were collected in two days with a primary electron beam energy of only 3.3 GeV, limiting the data from this run to smaller values of Q2 and scattering angle. Nonetheless, this measurement yields a data sample for ep with statistics comparable to those of the best previous measurements. We have shown that we can cleanly identify elastic scattering events and correct for the difference in acceptance for electron and positron scattering. Because we ran with only one polarity for the chicane, we are unable to study the difference between the incoming electron and positron beams. This systematic effect leads to the largest uncertainty in the final ratio of positron to electron scattering: R=1.0270.0050.05 for < Q2 >=0.206 GeV2 and 0.830 ? ? ? 0.943. We have demonstrated that the tertiary e beam generated using this technique provides the opportunity for dramatically improved comparisons of ep scattering, covering a significant range in both Q2 and scattering angle. Combining data with different chicane polarities will allow for detailed studies of the difference between the incoming e+ and e- beams.

Moteabbed, Maryam [Florida Institute of Technology; Niroula, Megh [Old Dominion University; Raue, Brian [Florida International University; Weinstein, Lawrence [Old Dominion University

2013-08-01T23:59:59.000Z