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Sample records for hard exclusive electroproduction

  1. What did we learn about GPDs from hard exclusive electroproduction of mesons

    SciTech Connect

    Kroll, Peter

    2011-10-24

    It is reported on an analysis of electroproduction of light mesons at small Bjorken-x (x{sup Bj}) within the handbag approach. The partonic subprocesses, meson electroproduction off quarks or gluons, are calculated within the modified per-turbative approach (m.p.a.) in which quark transverse momenta are retained. The soft hadronic matrix elements, generalized parton distributions (GPDs), are constructed by means of double distributions. The constraints from parton distributions and sum rules are taken into account. Various moments of these GPDs are compared to recent results from lattice gauge theories.

  2. Exclusive electroproduction of two pions at HERA

    NASA Astrophysics Data System (ADS)

    Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Antonelli, S.; Antonioli, P.; Antonov, A.; Arneodo, M.; Ashery, D.; Aushev, V.; Aushev, Y.; Bachynska, O.; Bamberger, A.; Barakbaev, A. N.; Barbagli, G.; Bari, G.; Barreiro, F.; Bartosik, N.; Bartsch, D.; Basile, M.; Behnke, O.; Behr, J.; Behrens, U.; Bellagamba, L.; Bertolin, A.; Bhadra, S.; Bindi, M.; Blohm, C.; Bokhonov, V.; Bołd, T.; Bondarenko, K.; Boos, E. G.; Borras, K.; Boscherini, D.; Bot, D.; Brock, I.; Brownson, E.; Brugnera, R.; Brümmer, N.; Bruni, A.; Bruni, G.; Brzozowska, B.; Bussey, P. J.; Bylsma, B.; Caldwell, A.; Capua, M.; Carlin, R.; Catterall, C. D.; Chekanov, S.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; Cooper-Sarkar, A. M.; Coppola, N.; Corradi, M.; Corriveau, F.; Costa, M.; D'Agostini, G.; Dal Corso, F.; del Peso, J.; Dementiev, R. K.; De Pasquale, S.; Derrick, M.; Devenish, R. C. E.; Dobur, D.; Dolgoshein, B. A.; Dolinska, G.; Doyle, A. T.; Drugakov, V.; Durkin, L. S.; Dusini, S.; Eisenberg, Y.; Ermolov, P. F.; Eskreys, S.; Fang, S.; Fazio, S.; Ferrando, J.; Ferrero, M. I.; Figiel, J.; Forrest, M.; Foster, B.; Gach, G.; Galas, A.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gialas, I.; Gladilin, L. K.; Gladkov, D.; Glasman, C.; Gogota, O.; Golubkov, Yu. A.; Göttlicher, P.; Grabowska-Bołd, I.; Grebenyuk, J.; Gregor, I.; Grigorescu, G.; Grzelak, G.; Gueta, O.; Gurvich, E.; Guzik, M.; Gwenlan, C.; Haas, T.; Hain, W.; Hamatsu, R.; Hart, J. C.; Hartmann, H.; Hartner, G.; Hilger, E.; Hochman, D.; Hori, R.; Horton, K.; Hüttmann, A.; Ibrahim, Z. A.; Iga, Y.; Ingbir, R.; Ishitsuka, M.; Jakob, H.-P.; Januschek, F.; Jones, T. W.; Jüngst, M.; Kadenko, I.; Kahle, B.; Kananov, S.; Kanno, T.; Karshon, U.; Karstens, F.; Katkov, I. I.; Kaur, M.; Kaur, P.; Keramidas, A.; Khein, L. A.; Kim, J. Y.; Kisielewska, D.; Kitamura, S.; Klanner, R.; Klein, U.; Koffeman, E.; Kooijman, P.; Korol, Ie.; Korzhavina, I. A.; Kotański, A.; Kötz, U.; Kowalski, H.; Kuprash, O.; Kuze, M.; Lee, A.; Levchenko, B. B.; Levy, A.; Libov, V.; Limentani, S.; Ling, T. Y.; Lisovyi, M.; Lobodzinska, E.; Lohmann, W.; Löhr, B.; Lohrmann, E.; Long, K. R.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; Maeda, J.; Magill, S.; Makarenko, I.; Malka, J.; Mankel, R.; Margotti, A.; Marini, G.; Martin, J. F.; Mastroberardino, A.; Mattingly, M. C. K.; Melzer-Pellmann, I.-A.; Mergelmeyer, S.; Miglioranzi, S.; Mohamad Idris, F.; Monaco, V.; Montanari, A.; Morris, J. D.; Mujkic, K.; Musgrave, B.; Nagano, K.; Namsoo, T.; Nania, R.; Nigro, A.; Ning, Y.; Nobe, T.; Noor, U.; Notz, D.; Nowak, R. J.; Nuncio-Quiroz, A. E.; Oh, B. Y.; Okazaki, N.; Oliver, K.; Olkiewicz, K.; Onishchuk, Yu.; Papageorgiu, K.; Parenti, A.; Paul, E.; Pawlak, J. M.; Pawlik, B.; Pelfer, P. G.; Pellegrino, A.; Perlański, W.; Perrey, H.; Piotrzkowski, K.; Pluciński, P.; Pokrovskiy, N. S.; Polini, A.; Proskuryakov, A. S.; Przybycień, M.; Raval, A.; Reeder, D. D.; Reisert, B.; Ren, Z.; Repond, J.; Ri, Y. D.; Robertson, A.; Roloff, P.; Rubinsky, I.; Ruspa, M.; Sacchi, R.; Salii, A.; Samson, U.; Sartorelli, G.; Savin, A. A.; Saxon, D. H.; Schioppa, M.; Schlenstedt, S.; Schleper, P.; Schmidke, W. B.; Schneekloth, U.; Schönberg, V.; Schörner-Sadenius, T.; Schwartz, J.; Sciulli, F.; Shcheglova, L. M.; Shehzadi, R.; Shimizu, S.; Singh, I.; Skillicorn, I. O.; Słomiński, W.; Smith, W. H.; Sola, V.; Solano, A.; Son, D.; Sosnovtsev, V.; Spiridonov, A.; Stadie, H.; Stanco, L.; Stern, A.; Stewart, T. P.; Stifutkin, A.; Stopa, P.; Suchkov, S.; Susinno, G.; Suszycki, L.; Sztuk-Dambietz, J.; Szuba, D.; Szuba, J.; Tapper, A. D.; Tassi, E.; Terrón, J.; Theedt, T.; Tiecke, H.; Tokushuku, K.; Tomalak, O.; Tomaszewska, J.; Tsurugai, T.; Turcato, M.; Tymieniecka, T.; Vázquez, M.; Verbytskyi, A.; Viazlo, O.; Vlasov, N. N.; Volynets, O.; Walczak, R.; Wan Abdullah, W. A. T.; Whitmore, J. J.; Wiggers, L.; Wing, M.; Wlasenko, M.; Wolf, G.; Wolfe, H.; Wrona, K.; Yagües-Molina, A. G.; Yamada, S.; Yamazaki, Y.; Yoshida, R.; Youngman, C.; Żarnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zeuner, W.; Zhautykov, B. O.; Zhmak, N.; Zhou, C.; Zichichi, A.; Zolkapli, Z.; Zolko, M.; Zotkin, D. S.

    2012-01-01

    The exclusive electroproduction of two pions in the mass range 0.4< M ππ <2.5 GeV has been studied with the ZEUS detector at HERA using an integrated luminosity of 82 pb-1. The analysis was carried out in the kinematic range of 2< Q 2<80 GeV2, 32< W<180 GeV and | t|<0.6 GeV2, where Q 2 is the photon virtuality, W is the photon-proton centre-of-mass energy and t is the squared four-momentum transfer at the proton vertex. The two-pion invariant-mass distribution is interpreted in terms of the pion electromagnetic form factor, | F( M ππ )|, assuming that the studied mass range includes the contributions of the ρ, ρ' and ρ'' vector-meson states. The masses and widths of the resonances were obtained and the Q 2 dependence of the cross-section ratios σ( ρ'→ ππ)/ σ( ρ) and σ( ρ''→ ππ)/ σ( ρ) was extracted. The pion form factor obtained in the present analysis is compared to that obtained in e + e -→ π + π -.

  3. Exclusive electroproduction of the rho+ meson on the proton @ CLAS

    SciTech Connect

    Ahmed Fradi

    2011-10-01

    We present preliminary results of the exclusive electroproduction of {rho}{sup +} on the proton at CLAS. We discuss the interpretation of the cross sections in terms of t-channel Reggeon exchanges and in terms of Generalized Parton Distributions (GPDs) formalism.

  4. Two Photon Exchange for Exclusive Pion Electroproduction

    SciTech Connect

    Afanaciev, Andrei V.; Aleksejevs, Aleksandrs G.; Barkanova, Svetlana G.

    2013-09-01

    We perform detailed calculations of two-photon-exchange QED corrections to the cross section of pion electroproduction. The results are obtained with and without the soft-photon approximation; analytic expressions for the radiative corrections are derived. The relative importance of the two-photon correction is analyzed for the kinematics of several experiments at Jefferson Lab. A significant, over 20%, effect due to two-photon exchange is predicted for the backward angles of electron scattering at large transferred momenta.

  5. A fresh look at exclusive electroproduction of light vector mesons

    NASA Astrophysics Data System (ADS)

    Meškauskas, M.; Müller, D.

    2014-02-01

    Relying on the collinear factorization approach, we demonstrate that H1 and ZEUS measurements of exclusive light vector meson and photon electroproduction cross sections can be simultaneously described for photon virtualities of . Our findings reveal that quark exchanges are important in this small region and that in leading order approximation the gluonic component is suppressed, e.g., the skewness ratio can be much smaller than one.

  6. Exclusive J/Psi electroproduction in a dual model

    SciTech Connect

    R. Fiore, L.L. Jenkovszky, V.K. Magas, S. Melis, A. Prokudin

    2009-12-01

    Exclusive J/Psi electroproduction is studied in the framework of the analytic S-matrix theory. The differential and integrated elastic cross sections are calculated using the Modified Dual Amplitude with Mandelstam Analyticity (M-DAMA) model. The model is applied to the description of the available experimantal data and proves to be valid in a wide region of the kinematical variables s, t and Q^2. Our amplitude can be used also as a universal background parametrization for the extraction of tiny resonance signals.

  7. Exclusive J/{psi} electroproduction in a dual model

    SciTech Connect

    Fiore, R.; Jenkovszky, L. L.; Magas, V. K.; Melis, S.; Prokudin, A.

    2009-12-01

    Exclusive J/{psi} electroproduction is studied in the framework of the analytic S-matrix theory. The differential and integrated elastic cross sections are calculated using the modified dual amplitude with Mandelstam analyticity model. The model is applied to the description of the available experimental data and proves to be valid in a wide region of the kinematical variables s, t, and Q{sup 2}. Our amplitude can be used also as a universal background parametrization for the extraction of tiny resonance signals.

  8. Nucleon Resonance Structure Studies via Exclusive KY Electroproduction

    NASA Astrophysics Data System (ADS)

    Carman, Daniel S.

    2016-10-01

    Studying the structure of excited nucleon states employing the electroproduction of exclusive reactions is an important avenue for exploring the nature of the non-perturbative strong interaction. The electrocouplings of N^* states in the mass range below 1.8 GeV have been determined from analyses of CLAS π N, η N, and π π N data. This work has made it clear that consistent results from independent analyses of several exclusive channels with different couplings and non-resonant backgrounds but the same N^* electro-excitation amplitudes, is essential to have confidence in the extracted results. In terms of hadronic coupling, many high-lying N^* states preferentially decay through the π π N channel instead of π N. Data from the KY channels will therefore be critical to provide an independent analysis to compare the extracted electrocouplings for the high-lying N^* states against those determined from the π N and π π {N} channels. A program to study excited N^* state structure in both non-strange and strange exclusive electroproduction channels using CLAS12 will measure differential cross sections and polarization observables to be used as input to extract the γ _v{it{NN}}^* electrocoupling amplitudes for the most prominent N^* states in the range of invariant energy W up 3 GeV in the virtually unexplored domain of momentum transfers Q^2 up to 12 GeV^2.

  9. Nucleon resonance structure studies via exclusive KY electroproduction

    DOE PAGES

    Carman, Daniel S.

    2016-06-16

    Studying the structure of excited nucleon states employing the electroproduction of exclusive reactions is an important avenue for exploring the nature of the non-perturbative strong interaction. The electrocouplings ofmore » $N^*$ states in the mass range below 1.8~GeV have been determined from analyses of CLAS $$\\pi N$$, $$\\eta N$$, and $$\\pi \\pi N$$ data. This work has made it clear that consistent results from independent analyses of several exclusive channels with different couplings and non-resonant backgrounds but the same $N^*$ electro excitation amplitudes, is essential to have confidence in the extracted results. In terms of hadronic coupling, many high-lying $N^*$ states preferentially decay through the $$\\pi \\pi N$$ channel instead of $$\\pi N$$. Data from the $KY$ channels will therefore be critical to provide an independent analysis to compare the extracted electrocouplings for the high-lying $N^*$ states against those determined from the $$\\pi N$$ and $$\\pi \\pi N$$ channels. Lastly, a program to study excited $N^*$ state structure in both non-strange and strange exclusive electroproduction channels using CLAS12 will measure differential cross sections and polarization observables to be used as input to extract the $$\\gamma_vNN^*$$ electrocoupling amplitudes for the most prominent $N^*$ states in the range of invariant energy $W$ up 3~GeV in the virtually unexplored domain of momentum transfers $Q^2$ up to 12~GeV$^2$.« less

  10. Nucleon resonance structure studies via exclusive KY electroproduction

    SciTech Connect

    Carman, Daniel S.

    2016-06-16

    Studying the structure of excited nucleon states employing the electroproduction of exclusive reactions is an important avenue for exploring the nature of the non-perturbative strong interaction. The electrocouplings of $N^*$ states in the mass range below 1.8~GeV have been determined from analyses of CLAS $\\pi N$, $\\eta N$, and $\\pi \\pi N$ data. This work has made it clear that consistent results from independent analyses of several exclusive channels with different couplings and non-resonant backgrounds but the same $N^*$ electro excitation amplitudes, is essential to have confidence in the extracted results. In terms of hadronic coupling, many high-lying $N^*$ states preferentially decay through the $\\pi \\pi N$ channel instead of $\\pi N$. Data from the $KY$ channels will therefore be critical to provide an independent analysis to compare the extracted electrocouplings for the high-lying $N^*$ states against those determined from the $\\pi N$ and $\\pi \\pi N$ channels. Lastly, a program to study excited $N^*$ state structure in both non-strange and strange exclusive electroproduction channels using CLAS12 will measure differential cross sections and polarization observables to be used as input to extract the $\\gamma_vNN^*$ electrocoupling amplitudes for the most prominent $N^*$ states in the range of invariant energy $W$ up 3~GeV in the virtually unexplored domain of momentum transfers $Q^2$ up to 12~GeV$^2$.

  11. Exclusive single pion electroproduction off the proton: Results from CLAS

    DOE PAGES

    Park, Kijun

    2016-08-13

    Exclusive meson electroproduction off protons is a powerful tool to probe the effective degrees of freedom in excited nucleon states at the varying distance scale where the transition from the contributions of both quark core and meson-baryon cloud to the quark core dominance. During the past decade, the CLAS collaboration has executed a broad experimental program to study the excited states of the proton using polarized electron beam and both polarized and unpolarized proton targets. The measurements covered a broad kinematic range in the invariant massmore » $W$ and photon virtuality $Q^2$ with nearly full coverage in polar and azimuthal angles in the hadronic CM system. As results, several low-lying nucleon resonance states in particular from pion threshold to $W < 1.6$ GeV have been explored. These include $$\\Delta$$(1232)$$\\frac{3}{2}^+$$, $$N(1440)\\frac{1}{2}^+$$, $$N(1520)\\frac{3}{2}^-$$, and $$N(1535)\\frac{1}{2}^-$$ states. In addition, we recently published the differential cross sections and helicity amplitudes of the reaction $$\\gamma^*p\\to n\\pi^+$$ at higher $W$ (1.6 to 2.0 GeV) which are the $$N(1675)\\frac{5}{2}^-$$, $$N(1680)\\frac{5}{2}^+$$, and $$N(1710)\\frac{1}{2}^+$$ states. These excited states with isospin $1/2$ and with masses near 1.7 GeV can be accessed in single $$n\\pi^+$$ production as there are no isospin $3/2$ states present in this mass range with the same spin-parity assignments. As a result, I will briefly discuss these states from CLAS results of the single charged pion electroproduction data.« less

  12. Exclusive single pion electroproduction off the proton: Results from CLAS

    SciTech Connect

    Park, Kijun

    2016-08-13

    Exclusive meson electroproduction off protons is a powerful tool to probe the effective degrees of freedom in excited nucleon states at the varying distance scale where the transition from the contributions of both quark core and meson-baryon cloud to the quark core dominance. During the past decade, the CLAS collaboration has executed a broad experimental program to study the excited states of the proton using polarized electron beam and both polarized and unpolarized proton targets. The measurements covered a broad kinematic range in the invariant mass $W$ and photon virtuality $Q^2$ with nearly full coverage in polar and azimuthal angles in the hadronic CM system. As results, several low-lying nucleon resonance states in particular from pion threshold to $W < 1.6$ GeV have been explored. These include $\\Delta$(1232)$\\frac{3}{2}^+$, $N(1440)\\frac{1}{2}^+$, $N(1520)\\frac{3}{2}^-$, and $N(1535)\\frac{1}{2}^-$ states. In addition, we recently published the differential cross sections and helicity amplitudes of the reaction $\\gamma^*p\\to n\\pi^+$ at higher $W$ (1.6 to 2.0 GeV) which are the $N(1675)\\frac{5}{2}^-$, $N(1680)\\frac{5}{2}^+$, and $N(1710)\\frac{1}{2}^+$ states. These excited states with isospin $1/2$ and with masses near 1.7 GeV can be accessed in single $n\\pi^+$ production as there are no isospin $3/2$ states present in this mass range with the same spin-parity assignments. As a result, I will briefly discuss these states from CLAS results of the single charged pion electroproduction data.

  13. Exclusive Single Pion Electroproduction off the Proton: Results from CLAS

    NASA Astrophysics Data System (ADS)

    Park, Kijun

    2016-11-01

    Exclusive meson electroproduction off protons is a powerful tool to probe the effective degrees of freedom in excited nucleon states at the varying distance scale where the transition from the contributions of both quark core and meson-baryon cloud to the quark core dominance. During the past decade, the CLAS collaboration has executed a broad experimental program to study the excited states of the proton using polarized electron beam and both polarized and unpolarized proton targets. The measurements covered a broad kinematic range in the invariant mass W and photon virtuality Q^2 with nearly full coverage in polar and azimuthal angles in the hadronic CM system. As results, several low-lying nucleon resonance states in particular from pion threshold to W < 1.6 GeV have been explored. These include Δ (1232)3/2^+, N(1440)1/2^+, N(1520)3/2^-, and N(1535)1/2^- states. In addition, we recently published the differential cross sections and helicity amplitudes of the reaction γ ^*p→ nπ ^+ at higher W (1.6-2.0 GeV) which are the N(1675)5/2^-, N(1680)5/2^+, and N(1710)1/2^+ states. These excited states with isospin 1/2 and with masses near 1.7 GeV can be accessed in single nπ ^+ production as there are no isospin 3/2 states present in this mass range with the same spin-parity assignments. I will briefly discuss these states from CLAS results of the single charged pion electroproduction data.

  14. Deeply virtual and exclusive electroproduction of omega mesons

    SciTech Connect

    Morand, L; Et. Al.

    2005-04-01

    The exclusive omega electroproduction off the proton was studied in a large kinematical domain above the nucleon resonance region and for the highest possible photon virtuality (Q{sup 2}) with the 5.75 GeV beam at CEBAF and the CLAS spectrometer. Cross sections were measured up to large values of the four-momentum transfer (-t < 2.7 GeV{sup 2}) to the proton. The contributions of the interference terms sigma{sub TT} and sigma{sub TL} to the cross sections, as well as an analysis of the omega spin density matrix, indicate that helicity is not conserved in this process. The t-channel pi{sup 0} exchange, or more generally the exchange of the associated Regge trajectory, seems to dominate the reaction {gamma}* p {yields} omega p, even for Q{sup 2} as large as 5 GeV{sub 2}. Contributions of handbag diagrams, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract for this process. Remarkably, the high-t behavior of the cross sections is nearly Q{sup 2}-independent, which may be interpreted as a coupling of the photon to a point-like object in this kinematical limit.

  15. Transverse-Target-Spin Asymmetry in Exclusive {omega}-Meson Electroproduction

    SciTech Connect

    Airapetian, A.; Akopov, N.; Akopov, Z.; Aschenauer, E. C.; Augustyniak, W.; Avetissian, A.; Belostotski, S.; Blok, H. P.; Borissov, A.; Bryzgalov, V.; Jackson, H. E.; Reimer, P. E.

    2015-12-17

    Hard exclusive electroproduction of omega mesons is studied with the HERMES spectrometer at the DESY laboratory by scattering 27.6 GeV positron and electron beams off a transversely polarized hydrogen target. The amplitudes of five azimuthal modulations of the single-spin asymmetry of the cross section with respect to the transverse proton polarization are measured. They are determined in the entire kinematic region as well as for two bins in photon virtuality and momentum transfer to the nucleon. Also, a separation of asymmetry amplitudes into longitudinal and transverse components is done. These results are compared to a phenomenological model that includes the pion pole contribution. Within this model, the data favor a positive pi omega transition form factor.

  16. Nucleon resonances in exclusive reactions of photo- and electroproduction of mesons

    SciTech Connect

    Skorodumina, Iu. A.; Burkert, V. D.; Golovach, E. N.; Gothe, R. W.; Isupov, E. L.; Ishkhanov, B. S.; Mokeev, V. I.; Fedotov, G. V.

    2015-11-01

    Methods for extracting nucleon resonance parameters from experimental data are reviewed. The formalism for the description of exclusive reactions of meson photo- and electroproduction off nucleons is discussed. Recent experimental data on exclusive meson production in the scattering of electrons and photons off protons are analyzed.

  17. Exclusive measurements of omega electroproduction off the proton in the resonance region

    SciTech Connect

    Phelps, Evan

    2014-01-01

    A complete theory of strong interactions must describe the excited baryon spectrum as well as the structure of prominent states, which reflects the dynamics of nonperturbative QCD. Beyond the discriminating power of exclusive single- and double-pion electroproduction, the omega channel provides an additional probe of high-mass excited states. The current analysis provides preliminary differential and integrated cross sections of omega electroproduction off the proton from W = 1.7 to 3.2 GeV and Q{sup 2} = 1.5 to 5.5 GeV{sup 2}. The data was collected by JLab's CLAS detector during two run periods and comprises the largest sample of exclusive resonance-region omega electroproduction ever analyzed. Preliminary Legendre decomposition of the cross sections supports previous indications of s-channel contributions to cross sections in the resonance region.

  18. Hard Exclusive Meson Production at COMPASS

    NASA Astrophysics Data System (ADS)

    Ter Wolbeek, Johannes

    2016-02-01

    The concept of Generalized Parton Distributions (GPDs) combines two-dimensional spatial information given by form factors, with longitudinal momentum information from Parton Distribution Functions. GPDs provide comprehensive description of the nucleon structure involving a wealth of new information. For instance, according to Ji’s sum rule, the GPDs H and E enable access to the total angular momenta of quarks, antiquarks and gluons. While H can be approached using measurements of electroproduction cross sections, asymmetry measurements in hard exclusive meson production off transversely polarized targets can help to constrain the GPD E and chiral-odd GPDs. In 2007 and 2010 the COMPASS experiment at CERN collected data by scattering a 160GeV/c muon beam off a transversely polarized NH3 target. Exclusive vector-meson production μ + p → μ‧ + p + V with a ρ0 or ω meson in the final state is studied and five single-spin and three double-spin azimuthal asymmetries are measured.

  19. Global analysis of exclusive kaon and pion electroproduction

    NASA Astrophysics Data System (ADS)

    Horn, T.

    2012-01-01

    The p(e,e'π+)n and p(e,e',K+)Λ (Σ0) reactions are important tools in the study of hadron structure. In particular, the flavor degree of freedom introduced with the addition of the strange quark helps us understand the reaction mechanism underlying strangeness production, and the transition from hadronic to partonic degrees of freedom in exclusive processes. In this study, we examine the world's data on exclusive p(e,e'π+)n and p(e,e'K+)Λ cross sections. The data were combined into a superset with one global uncertainty, and examined for -t dependence of the longitudinal and transverse components of the cross section as function of Q2 and the longitudinal momentum fraction, xB. The data suggest that the importance of t-channel meson exchange decreases at higher values of xB. The Q2 dependence of the longitudinal to transverse cross section ratio was compared with the Q2-scaling expectation for hard exclusive processes.

  20. Exclusive Electroproduction of meson rho on the nucleon Virtualite Intermediate With the CLAS Detector at Jlab; Electroproduction Exclusive de meson rho sur le nucleon Virtualite Intermediaire Avec le Detecteur CLAS at Jlab

    SciTech Connect

    Hadjidakis, Cynthia

    2002-12-17

    This report presents the exclusive rho0 meson electroproduction on the nucleon at intermediate square momentum transfers Q2 (1.5 < Q2 < 3 GeV2) and above the resonance region. The experiment has been taken place at the Jefferson laboratory with the CLAS detector, with a 4.2 GeV beam energy on a hydrogen target in the February-March 1999 period. They present the results and in particular the L/T separated cross sections. This experimentally unexplored domain experimentally is at the intersection between traditional ''soft'' hadronic physics models (VDM and Regge inspired models) and ''hard'' pQCD inspired approaches (recently introduced Generalized Parton Distribution). They discuss both approaches and their domain of validity.

  1. Separated Response Function Ratios in Exclusive, Forward π± Electroproduction

    NASA Astrophysics Data System (ADS)

    Huber, G. M.; Blok, H. P.; Butuceanu, C.; Gaskell, D.; Horn, T.; Mack, D. J.; Abbott, D.; Aniol, K.; Anklin, H.; Armstrong, C.; Arrington, J.; Assamagan, K.; Avery, S.; Baker, O. K.; Barrett, B.; Beise, E. J.; Bochna, C.; Boeglin, W.; Brash, E. J.; Breuer, H.; Chang, C. C.; Chant, N.; Christy, M. E.; Dunne, J.; Eden, T.; Ent, R.; Fenker, H.; Gibson, E. F.; Gilman, R.; Gustafsson, K.; Hinton, W.; Holt, R. J.; Jackson, H.; Jin, S.; Jones, M. K.; Keppel, C. E.; Kim, P. H.; Kim, W.; King, P. M.; Klein, A.; Koltenuk, D.; Kovaltchouk, V.; Liang, M.; Liu, J.; Lolos, G. J.; Lung, A.; Margaziotis, D. J.; Markowitz, P.; Matsumura, A.; McKee, D.; Meekins, D.; Mitchell, J.; Miyoshi, T.; Mkrtchyan, H.; Mueller, B.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pentchev, L.; Perdrisat, C.; Pitz, D.; Potterveld, D.; Punjabi, V.; Qin, L. M.; Reimer, P. E.; Reinhold, J.; Roche, J.; Roos, P. G.; Sarty, A.; Shin, I. K.; Smith, G. R.; Stepanyan, S.; Tang, L. G.; Tadevosyan, V.; Tvaskis, V.; van der Meer, R. L. J.; Vansyoc, K.; Van Westrum, D.; Vidakovic, S.; Volmer, J.; Vulcan, W.; Warren, G.; Wood, S. A.; Xu, C.; Yan, C.; Zhao, W.-X.; Zheng, X.; Zihlmann, B.; Jefferson Lab Fπ Collaboration

    2014-05-01

    The study of exclusive π± electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σLπ-/σLπ+ is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σTπ-/σTπ+ from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π± electroproduction on the deuteron at central Q2 values of 0.6, 1.0, 1.6 GeV2 at W =1.95 GeV, and Q2=2.45 GeV2 at W =2.22 GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

  2. Nucleon Resonance Structure from Exclusive Meson Electroproduction with CLAS and CLAS12

    SciTech Connect

    Philip L. Cole, Volker D. Burkert, Ralf W. Gothe, Victor I. Mokeev

    2012-12-01

    The CLAS detector at Jefferson Lab is a unique instrument, which has provided the lion's share of the world's data on meson photo- and electroproduction in the resonance excitation region. The electroexcitation amplitudes for the low-lying resonances P{sub 33} (1232), P{sub 11} (1440), D{sub 13} (1520), and S {sub 11} (1535) were determined over a wide range of Q{sub 2} < 5.0 GeV{sub 2} in a comprehensive analysis of exclusive single-meson ( {pi}{sup +} n, {pi}{sup 0} p) reactions in the electroproduction off protons. Further, we were able to precisely measure {pi}{sup +}{pi}{sup -}p electroproduction differential cross sections provided by the nearly full kinematic coverage of the CLAS detector. And, for the first time, the electrocouplings of the P{sub 11} (1440), D{sub 13} (1520) excited states are determined from the exclusive-{pi}{sup +}{pi}{sup -}p reaction. Consistent results on the electrocouplings from two-independent analyses (single- and double-pion electroproduction) have provided compelling evidence for the reliable extraction of the N* electrocouplings. And preliminary results on the electrocouplings of the S{sub 31} (1620), S{sub 11} (1650), D{sub 33} (1700), and P{sub 13} (1720) states, which decay preferentially to the N{pi} {pi} final states, have recently become available. Theoretical analyses of these results have revealed that there are two major contributions to the resonance structure: a) an internal quark core and b) an external meson-baryon cloud. These CLAS results have had considerable impact on QCD-based studies on N* structure and in the search for manifestations of the dynamical masses of the dressed quarks. Future CLAS12 N* structure studies at high photon virtualities will considerably extend our capabilities in exploring the nature of confinement in baryons.

  3. Separated response function ratios in exclusive, forward π(±) electroproduction.

    PubMed

    Huber, G M; Blok, H P; Butuceanu, C; Gaskell, D; Horn, T; Mack, D J; Abbott, D; Aniol, K; Anklin, H; Armstrong, C; Arrington, J; Assamagan, K; Avery, S; Baker, O K; Barrett, B; Beise, E J; Bochna, C; Boeglin, W; Brash, E J; Breuer, H; Chang, C C; Chant, N; Christy, M E; Dunne, J; Eden, T; Ent, R; Fenker, H; Gibson, E F; Gilman, R; Gustafsson, K; Hinton, W; Holt, R J; Jackson, H; Jin, S; Jones, M K; Keppel, C E; Kim, P H; Kim, W; King, P M; Klein, A; Koltenuk, D; Kovaltchouk, V; Liang, M; Liu, J; Lolos, G J; Lung, A; Margaziotis, D J; Markowitz, P; Matsumura, A; McKee, D; Meekins, D; Mitchell, J; Miyoshi, T; Mkrtchyan, H; Mueller, B; Niculescu, G; Niculescu, I; Okayasu, Y; Pentchev, L; Perdrisat, C; Pitz, D; Potterveld, D; Punjabi, V; Qin, L M; Reimer, P E; Reinhold, J; Roche, J; Roos, P G; Sarty, A; Shin, I K; Smith, G R; Stepanyan, S; Tang, L G; Tadevosyan, V; Tvaskis, V; van der Meer, R L J; Vansyoc, K; Van Westrum, D; Vidakovic, S; Volmer, J; Vulcan, W; Warren, G; Wood, S A; Xu, C; Yan, C; Zhao, W-X; Zheng, X; Zihlmann, B

    2014-05-09

    The study of exclusive π(±) electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio RL=σL(π-)/σL(π+) is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of RT=σT(π-)/σT(π+) from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to perturbative QCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π(±) electroproduction on the deuteron at central Q(2) values of 0.6, 1.0, 1.6  GeV(2) at W=1.95  GeV, and Q(2)=2.45  GeV(2) at W=2.22  GeV. Here, we present the L and T cross sections, with emphasis on RL and RT, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for RT are consistent with a transition between pion knockout and quark knockout mechanisms.

  4. Measurement of Exclusive $π^0$ Electroproduction Structure Functions and their Relationship to Transverse Generalized Parton Distributions

    SciTech Connect

    Bedlinskiy, Ivan; Niccolai, Silvia; Stoler, Paul; Adhikari, Krishna; Aghasyan, Mher; Amaryan, Moskov; Anghinolfi, Marco; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Ball, Jacques; Baltzell, Nathan; Battaglieri, Marco; Bennett, Robert; Biselli, Angela; Bookwalter, Craig; Boyarinov, Sergey; Briscoe, William; Brooks, Williams; Burkert, Volker; Carman, Daniel; Celentano, Andrea; Chandavar, Shloka; Charles, Gabriel; Contalbrigo, Marco; Crede, Volker; D'Angelo, Annalisa; Daniel, Aji; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Deur, Alexandre; Djalali, Chaden; Doughty, David; Dupre, Raphael; Egiyan, Hovanes; El Alaoui, Ahmed; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Fegan, Stuart; Fleming, Jamie; Forest, Tony; Garcon, Michel; Gevorgyan, Nerses; Giovanetti, Kevin; Girod, Francoi-Xavier; Gohn, Wesley; Gothe, Ralf; Graham, Lewis; Griffioen, Keith; Guegan, Baptiste; Guidal, Michel; Guo, Lei; Hafidi, Kawtar; Hakobyan, Hayk; Hanretty, Charles; Heddle, David; Hicks, Kenneth; Holtrop, Maurik; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Jo, Hyon-Suk; Joo, Kyungseon; Keller, Dustin; Khanddaker, Mahbubul; Khertarpal, Puneet; Kim, Andrey; Kim, Wooyoung; Klein, Franz; Koirala, Suman; Kubarovsky, A; Kuhn, Sebastian; Kuleshov, Sergey; Kvaltine, Nicholas; Livingston, Kenneth; Lu, Haiyun; MacGregor, Ian; Mao, Yuqing; Markov, Nikolai; Martinez, D; Mayer, Michael; McKinnon, Bryan; Meyer, Curtis; Mineeva, Taisiya; Mirazita, Marco; Mokeev, Viktor; Moutarde, Herve; Munevar Espitia, Edwin; Munoz Camacho, Carlos; Nadel-Turonski, Pawel; Niculescu, Gabriel; Niculescu, Maria-Ioana; Osipenko, Mikhail; Ostrovidov, Alexander; Pappalardo, Luciano; Permuzyan, Rafayel; Park, Kijun; Park, Sungkyun; Pasyuk, Eugene; Pereira, Sergio; Phelps, Evan; Pisano, Silvia; Pogorelko, Oleg; Pozdnyakov, Sergey; Price, John; Procureur, Sebastien; Prok, Yelena; Protopopescu, Dan; Puckett, Andrew; Raue, Brian; Ricco, Giovanni; Rimal, Dipak; Ripani, Marco; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Saini, Mukesh; Salgado, Carlos; Saylor, Nicholas; Schott, Diane; Schumacher, Reinhard; Seder, Erin; Seraydaryan, Heghine; Sharabian, Youri; Smith, Gregory; Sober, Daniel; Sokhan, Daria; Stepanyan, Samuel; Strauch, Steffen; Taiuti, Mauro; Tang, Wei; Taylor, Charles; Tian, Ye; Tkachenko, Svyatoslav; Ungaro, Maurizio; Vineyard, Michael; Vlasov, Alexander; Voskanyan, Hakob; Voutier, Eric; Walford, Natalie; Watts, Daniel; Weinstein, Lawrence; Weygan, Dennis; Wood, Michael; Zachariou, Nicholas; Zhang, Jixie; Zhao, Zhiwen; Zonta, Irene

    2012-09-01

    Exclusive $\\pi^0$ electroproduction at a beam energy of 5.75 GeV has been measured with the Jefferson Lab CLAS spectrometer. Differential cross sections were measured at more than 1800 kinematic values in $Q^2$, $x_B$, $t$, and $\\phi_\\pi$, in the $Q^2$ range from 1.0 to 4.6 GeV$^2$,\\ $-t$ up to 2 GeV$^2$, and $x_B$ from 0.1 to 0.58. Structure functions $\\sigma_T +\\epsilon \\sigma_L, \\sigma_{TT}$ and $\\sigma_{LT}$ were extracted as functions of $t$ for each of 17 combinations of $Q^2$ and $x_B$. The data were compared directly with two handbag-based calculations including both longitudinal and transversity GPDs. Inclusion of only longitudinal GPDs very strongly underestimates $\\sigma_T +\\epsilon \\sigma_L$ and fails to account for $\\sigma_{TT}$ and $\\sigma_{LT}$, while inclusion of transversity GPDs brings the calculations into substantially better agreement with the data. There is very strong sensitivity to the relative contributions of nucleon helicity flip and helicity non-flip processes. The results confirm that exclusive $\\pi^0$ electroproduction offers direct experimental access to the transversity GPDs.

  5. Exclusive rho^0 electroproduction on the proton at CLAS

    SciTech Connect

    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

    2009-01-01

    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

  6. Exclusive pi- Electroproduction off the Neutron in Deuterium in the Resonance Region

    SciTech Connect

    Tian, Ye; Gothe, Ralf W.

    2016-03-01

    The goal of our research is to provide the exclusive γ*(n) → p+π− reaction cross section from deuterium data using the correction factor that account for the final state re-scattering that can be determined from the data set itself. The “e1e” Jefferson Lab CLAS data set that we analyze includes both a hydrogen and deuterium target run period, which allows a combined analysis of pion electroproduction off the free proton, the bound proton, and the bound neutron under the same experimental conditions. Hence it will provide the experimentally best possible information about the off-shell and final state interaction effects in deuterium, which must be considered in order to extract the neutron information. This data set will provide results with a kinematic coverage for the hadronic invariant mass W up to 1.7 GeV and in the momentum transfer Q2 range of 0.4 − 1.0 GeV/c2. The cross section analysis of this data set is currently underway, which will considerably improve our knowledge of the Q2 evolution of π−p electroproduction cross sections off bound neutron needed for the extraction of excited neutron state electrocouplings for the first time.

  7. Exclusive η electroproduction at W >2 GeV with CLAS and transversity generalized parton distributions

    NASA Astrophysics Data System (ADS)

    Bedlinskiy, I.; Kubarovsky, V.; Stoler, P.; Adhikari, K. P.; Akbar, Z.; Anefalos Pereira, S.; Avakian, H.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Fersch, R.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Garçon, M.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Hicks, K.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khachatryan, G.; Khachatryan, M.; Khandaker, M.; Kim, A.; Kim, W.; Klein, F. J.; Kuhn, S. E.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; MacGregor, I. J. D.; Markov, N.; McKinnon, B.; Meziani, Z. E.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Saini, M. S.; Salgado, C.; Schumacher, R. A.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Torayev, B.; Turisini, M.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Yurov, M.; Zachariou, N.; Zhang, J.; Zonta, I.; CLAS Collaboration

    2017-03-01

    The cross section of the exclusive η electroproduction reaction e p →e'p'η was measured at Jefferson Laboratory with a 5.75 GeV electron beam and the CLAS detector. Differential cross sections d4σ /d t d Q2d xBd ϕη and structure functions σU=σT+ɛ σL,σT T , and σL T, as functions of t , were obtained over a wide range of Q2 and xB. The η structure functions are compared with those previously measured for π0 at the same kinematics. At low t , both π0 and η are described reasonably well by generalized parton distributions (GPDs) in which chiral-odd transversity GPDs are dominant. The π0 and η data, when taken together, can facilitate the flavor decomposition of the transversity GPDs.

  8. Single and double polarization asymmetries from deeply virtual exclusive pi^0 electroproduction

    SciTech Connect

    Kim, Andrey; Avakian, Harut A.; Burkert, Volker D.

    2014-10-01

    The target and double spin asymmetry measurements of exclusive p0 electroproduction were performed for the first time in DIS region at Jefferson Lab using the CEBAF Large Acceptance Spectrometer (CLAS) and longitudinally polarized proton target. The wide kinematic coverage and good resolution of CLAS allowed measurements in full azimuthal range providing an opportunity to extract single and double spin asymmetries proportional to polarized structure functions. Their angular dependencies in hadronic center-of-mass system were analyzed, and extracted moments are compared to recent theoretical handbag-based calculations based on chiral-even and chiral-odd GPDs contributions. The interpretation of present results within the framework of the modified perturbative approach and their use as a constraint for models of the t behavior will be discussed.

  9. Exclusive η electroproduction at W>2 GeV with CLAS and transversity generalized parton distributions

    DOE PAGES

    Bedlinskiy, I.; Kubarovsky, V.; Stoler, P.; ...

    2017-03-10

    The cross section of the exclusive η electroproduction reaction ep → e'p'η was measured at Jefferson Laboratory with a 5.75 GeV electron beam and the CLAS detector. Differential cross sections d4σ/dtdQ2dxBdΦη and structure functions σU = σT + εσL, σTT, and σLT, as functions of t, were obtained over a wide range of Q2 and xB. The η structure functions are compared with those previously measured for π0 at the same kinematics. At low t, both π0 and η are described reasonably well by generalized parton distributions (GPDs) in which chiral-odd transversity GPDs are dominant. As a result, the π0more » and η data, when taken together, can facilitate the flavor decomposition of the transversity GPDs.« less

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

    SciTech Connect

    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; Sabatié, 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

    2014-08-01

    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 σLT 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.

  11. Separated response functions in exclusive, forward π± electroproduction on deuterium

    NASA Astrophysics Data System (ADS)

    Huber, G. M.; Blok, H. P.; Butuceanu, C.; Gaskell, D.; Horn, T.; Mack, D. J.; Abbott, D.; Aniol, K.; Anklin, H.; Armstrong, C.; Arrington, J.; Assamagan, K.; Avery, S.; Baker, O. K.; Barrett, B.; Beise, E. J.; Bochna, C.; Boeglin, W.; Brash, E. J.; Breuer, H.; Chang, C. C.; Chant, N.; Christy, M. E.; Dunne, J.; Eden, T.; Ent, R.; Fenker, H.; Gibson, E. F.; Gilman, R.; Gustafsson, K.; Hinton, W.; Holt, R. J.; Jackson, H.; Jin, S.; Jones, M. K.; Keppel, C. E.; Kim, P. H.; Kim, W.; King, P. M.; Klein, A.; Koltenuk, D.; Kovaltchouk, V.; Liang, M.; Liu, J.; Lolos, G. J.; Lung, A.; Margaziotis, D. J.; Markowitz, P.; Matsumura, A.; McKee, D.; Meekins, D.; Mitchell, J.; Miyoshi, T.; Mkrtchyan, H.; Mueller, B.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pentchev, L.; Perdrisat, C.; Pitz, D.; Potterveld, D.; Punjabi, V.; Qin, L. M.; Reimer, P. E.; Reinhold, J.; Roche, J.; Roos, P. G.; Sarty, A.; Shin, I. K.; Smith, G. R.; Stepanyan, S.; Tang, L. G.; Tadevosyan, V.; Tvaskis, V.; van der Meer, R. L. J.; Vansyoc, K.; Van Westrum, D.; Vidakovic, S.; Volmer, J.; Vulcan, W.; Warren, G.; Wood, S. A.; Xu, C.; Yan, C.; Zhao, W.-X.; Zheng, X.; Zihlmann, B.; Jefferson Lab Fπ Collaboration

    2015-01-01

    Background: Measurements of forward exclusive meson production at different squared four-momenta of the exchanged virtual photon, Q2, and at different four-momentum transfer, t , can be used to probe QCD's transition from meson-nucleon degrees of freedom at long distances to quark-gluon degrees of freedom at short scales. Ratios of separated response functions in π- and π+ electroproduction are particularly informative. The ratio for transverse photons may allow this transition to be more easily observed, while the ratio for longitudinal photons provides a crucial verification of the assumed pole dominance, needed for reliable extraction of the pion form factor from electroproduction data. Purpose: We perform the first complete separation of the four unpolarized electromagnetic structure functions L /T /L T /T T in forward, exclusive π± electroproduction on deuterium above the dominant resonances. Method: Data were acquired with 2.6-5.2-GeV electron beams and the HMS +SOS spectrometers in Jefferson Lab Hall C at central Q2 values of 0.6, 1.0, and 1.6 GeV2 at W =1.95 GeV, and Q2=2.45 GeV2 at W =2.22 GeV. There was significant coverage in ϕ and ɛ , which allowed separation of σL ,T ,L T ,T T. Results: σL shows a clear signature of the pion pole, with a sharp rise at small -t . In contrast, σT is much flatter versus t . The longitudinal/transverse ratios evolve with Q2 and t and at the highest Q2=2.45 GeV2 show a slight enhancement for π- production compared to π+. The π-/π+ ratio for transverse photons exhibits only a small Q2 dependence, following a nearly universal curve with t , with a steep transition to a value of about 0.25, consistent with s -channel quark knockout. The σT T/σT ratio also drops rapidly with Q2, qualitatively consistent with s -channel helicity conservation. The π-/π+ ratio for longitudinal photons indicates a small isoscalar contamination at W =1.95 GeV, consistent with what was observed in our earlier determination of the

  12. Exclusive π0 electroproduction at W >2 GeV with CLAS

    NASA Astrophysics Data System (ADS)

    Bedlinskiy, I.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Anderson, M. D.; Anefalos Pereira, S.; 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.; Garçon, 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.; Sabatié, 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.; CLAS Collaboration

    2014-08-01

    Exclusive neutral-pion electroproduction (ep→e'p'π0) was measured at Jefferson Lab with a 5.75-GeV electron beam and the CLAS detector. Differential cross sections d4σ/dtdQ2dxBdϕπ and structure functions σT+ɛσL,σTT, and σLT 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.

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

    SciTech Connect

    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

    2013-01-01

    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

  14. Deep Exclusive PI0 and ETA Electroproduction with CLAS at Jefferson Lab

    NASA Astrophysics Data System (ADS)

    Stoler, Paul

    2012-03-01

    The CLAS collaboration at Jefferson Lab has undertaken a series of measurements of exclusive 0̂ and η electroproduction at a beam energy 6 GeV over a large kinematic coverage in Q^2, t and xB. New results of extracted structure functions σL+σT, σLT and σTT, are presented in the kinematic range Q^2 from 1.2 to 3.2 GeV^2/c^2, |t| from |tmin| to 1.2 GeV^2/c^2 and xB from 0.1 to 0.6. Recent theoretical work [1,2] indicate that pseudoscalar meson production is uniquely sensitive to quark helicity-flip processes. The new results, together with CLAS measurements of beam spin asymmetries Aφ [3] and cross section ratios σ(π0)/σ(η) , compared with theoretical calculations [1,2] that are based on the helicity-flip transversity GPDs, provide supporting evidence that pseudoscalar meson production at these kinematics may be dominated by the handbag mechanism and helicity-flip transversity GPDs. [4pt] [1] S.V.Goloskokov and P.Kroll, Eur.Phys.J. A47,112 (2011).[0pt] [2] G.R. Goldstein,J.O.Gonzalez and S.Liuti, Phys. Rev., D84,034007(2011).[0pt] [3] R.DeMasi,et,al.(CLAS Collaboration),Phys.Rev.,C77,042201(2008)

  15. Nucleon Resonance Electrocouplings from the CLAS Data on Exclusive Meson Electroproduction off Protons

    SciTech Connect

    Victor I. Mokeev, Inna G. Aznauryan, Volker D. Burkert

    2011-12-01

    {gamma}{sub v}NN* transition helicity amplitudes (electrocouplings) of several prominent excited proton states are determined for the first time in independent analyses of {pi}{sup +}n, {pi}{sup 0}p, and {pi}{sup +}{pi}{sup -}p electroproduction off protons. Consistent results on resonance electrocouplings obtained from major meson electroproduction channels offer an evidence for reliable extraction of these fundamental quantities. Analysis of {pi}{sup +}{pi}{sup -}p electroproduction has extended considerably information on electrocouplings of high lying N* states, which decay preferentially to the N{pi}{pi} final states.

  16. Separated response functions in exclusive, forward π± electroproduction on deuterium

    DOE PAGES

    Huber, G. M.; Blok, H. P.; Butuceanu, C.; ...

    2015-01-07

    Background: Measurements of forward exclusive meson production at different squared four-momenta of the exchanged virtual photon, Q2, and at different four-momentum transfer, t, can be used to probe QCD's transition from meson-nucleon degrees of freedom at long distances to quark-gluon degrees of freedom at short scales. Ratios of separated response functions in π⁻ and π⁺ electroproduction are particularly informative. Ratio for transverse photons may allow this transition to be more easily observed, while the ratio for longitudinal photons provides a crucial verification of the assumed pole dominance, needed for reliable extraction of the pion form factor from electroproduction data. Method:more » Data were acquired with 2.6-5.2 GeV electron beams and the HMS+SOS spectrometers in Jefferson Lab Hall C, at central Q2 values of 0.6, 1.0, 1.6 GeV2 at W=1.95 GeV, and Q2=2.45 GeV2 at W=2.22 GeV. There was significant coverage in Φ And ϵ, which allowed separation of σL,T,LT,TT. Results: σL shows a clear signature of the pion pole, with a sharp rise at small -t. In contrast, σT is much flatter versus t. The longitudinal/transverse ratios evolve with Q2 and t, and at the highest Q2=2.45 GeV2 show a slight enhancement for π⁻ Production compared to π⁺. The π⁻/π⁺+ ratio for transverse photons exhibits only a small Q2-dependence, following a nearly universal curve with t, with a steep transition to a value of about 0.25, consistent with s-channel quark knockout. The σTT/σT ratio also drops rapidly with Q2, qualitatively consistent with s-channel helicity conservation. The π⁻/π⁺ ratio for longitudinal photons indicates a small isoscalar contamination at W=1.95 GeV, consistent with what was observed in our earlier determination of the pion form factor at these kinematics.« less

  17. Hard Exclusive Vector Meson Leptoproduction At HERMES

    SciTech Connect

    Golembiovskaya, M.

    2011-07-15

    The HERMES experiment at DESY, Hamburg collected a set of data on hard exclusive vector meson ({rho}{sup 0}{phi},{omega}) leptoproduction using the 27.6 GeV longitudinally polarized lepton beam of HERA accelerator and longitudinally or transversely polarized or unpolarized gas targets. Measurements of exclusive vector meson production provide access to the structure of the nucleon since the process can be described in terms of Generalized Parton Distributions (GPDs). An overview of the HERMES results on exclusive vector mesons production is presented.

  18. Radiative effects in the processes of exclusive photon electroproduction from polarized protons

    SciTech Connect

    Igor Akushevich, Alexander Ilyichev

    2012-03-01

    Radiative effects in the electroproduction of photons in polarized ep-scattering are calculated in the leading log approximation and analyzed numerically for kinematical conditions of current measurement at Jefferson Lab. Radiative corrections to the cross sections, their azimuthal distributions and Fourier coefficients are in particular focus. Kinematical regions where the radiative corrections are considerable are identified.

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

    SciTech Connect

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

    2006-11-19

    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.

  20. Precise π^-/π^+ Ratios from Exclusive Forward Pion Electroproduction on the Deuteron \\unboldmath

    NASA Astrophysics Data System (ADS)

    Mkrtchyan, Hamlet

    1998-10-01

    for the Charged Pion Form Factor (F_π) Collaboration at the Thomas Jefferson National Accelerator Facility (TJNAF). During the F_π experiment E93-021, forward charged pion electroproduction data were acquired on a Deuterium target over a -t range of 0.02-0.50 GeV^2. The goal of this experiment is to extract F_π(Q^2) from the pion pole-dominated forward longitudinal response, so a thorough understanding of the physics backgrounds is necessary. The cross-section ratio π^-/π^+ is sensitive to the reaction mechanism, and the longitudinal and transverse separated ratios are even more revealing. Preliminary ratios will be presented and compared with the recent Regge model calculations of Vanderhaeghen et al.

  1. Separated Response Function Ratios in Exclusive, Forward π± Electroproduction

    SciTech Connect

    Huber, G. M.; Blok, H. P.; Butuceanu, C.; Gaskell, D.; Horn, T.; Mack, D. J.; Abbott, D.; Aniol, K.; Anklin, H.; Armstrong, C.; Arrington, J.; Assamagan, K.; Avery, S.; Baker, O. K.; Barrett, B.; Beise, E. J.; Bochna, C.; Boeglin, W.; Brash, E. J.; Breuer, H.; Chang, C. C.; Chant, N.; Christy, M. E.; Dunne, J.; Eden, T.; Ent, R.; Fenker, H.; Gibson, E. F.; Gilman, R.; Gustafsson, K.; Hinton, W.; Holt, R. J.; Jackson, H.; Jin, S.; Jones, M. K.; Keppel, C. E.; Kim, P. H.; Kim, W.; King, P. M.; Klein, A.; Koltenuk, D.; Kovaltchouk, V.; Liang, M.; Liu, J.; Lolos, G. J.; Lung, A.; Margaziotis, D. J.; Markowitz, P.; Matsumura, A.; McKee, D.; Meekins, D.; Mitchell, J.; Miyoshi, T.; Mkrtchyan, H.; Mueller, B.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pentchev, L.; Perdrisat, C.; Pitz, D.; Potterveld, D.; Punjabi, V.; Qin, L. M.; Reimer, P. E.; Reinhold, J.; Roche, J.; Roos, P. G.; Sarty, A.; Shin, I. K.; Smith, G. R.; Stepanyan, S.; Tang, L. G.; Tadevosyan, V.; Tvaskis, V.; van der Meer, R. L. J.; Vansyoc, K.; Van Westrum, D.; Vidakovic, S.; Volmer, J.; Vulcan, W.; Warren, G.; Wood, S. A.; Xu, C.; Yan, C.; Zhao, W. -X.; Zheng, X.; Zihlmann, B.

    2014-05-01

    The study of exclusive π{sup ±} electroproduction on the nucleon, including separation of the various structure functions, is of interest for a number of reasons. The ratio R{sub L}=σ{sup π{sup -}}{sub L}/σ{sup π{sup +}}{sub L} is sensitive to isoscalar contamination to the dominant isovector pion exchange amplitude, which is the basis for the determination of the charged pion form factor from electroproduction data. A change in the value of R{sub T}=σ{sup π{sup -}}{sub T}/σ{sup π{sup +}}{sub T} from unity at small -t, to 1/4 at large -t, would suggest a transition from coupling to a (virtual) pion to coupling to individual quarks. Furthermore, the mentioned ratios may show an earlier approach to pQCD than the individual cross sections. We have performed the first complete separation of the four unpolarized electromagnetic structure functions above the dominant resonances in forward, exclusive π± electroproduction on the deuteron at central Q{sup 2} values of 0.6, 1.0, 1.6 GeV{sup 2} at W=1.95 GeV, and Q{sup 2}=2.45 GeV{sup 2} at W=2.22 GeV. Here, we present the L and T cross sections, with emphasis on R{sub L} and R{sub T}, and compare them with theoretical calculations. Results for the separated ratio RL indicate dominance of the pion-pole diagram at low -t, while results for R{sub T} are consistent with a transition between pion knockout and quark knockout mechanisms.

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

    SciTech Connect

    Park, Kijun

    2014-09-01

    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.

  3. QED radiative effects in the processes of exclusive photon electroproduction from polarized protons with the next-to-leading accuracy

    SciTech Connect

    Akushevich, Igor V.; Ilyichev, Alexander; Shumeiko, Nikolai M

    2014-08-01

    Radiative effects in the electroproduction of photons in polarized ep-scattering are calculated with the next-to-leading (NLO) accuracy. The contributions of loops and two photon emission were presented in analytical form. The covariant approach of Bardin and Shumeiko was used to extract the infrared divergence. All contributions to the radiative correction were presented in the form of the correction to the leptonic tensor thus allowing for further applications in other experiments, e.g., deep inelastic scattering. The radiative corrections (RC) to the cross sections and polarization asymmetries were analyzed numerically for kinematical conditions of the current measurement at Jefferson Lab. Specific attention was paid on analyzing kinematical conditions for the process with large radiative effect when momenta of two photons in the final state are collinear to momenta of initial and final electrons, respectively.

  4. Target and beam-target spin asymmetries in exclusive π+ and π- electroproduction with 1.6- to 5.7-GeV electrons

    NASA Astrophysics Data System (ADS)

    Bosted, P. E.; Biselli, A. S.; Careccia, S.; Dodge, G.; Fersch, R.; Guler, N.; Kuhn, S. E.; Pierce, J.; Prok, Y.; Zheng, X.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Asryan, G.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Boiarinov, S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Garçon, M.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Minehart, R.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sparveris, N.; Stankovic, Ivana; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2016-11-01

    Beam-target double-spin asymmetries and target single-spin asymmetries in exclusive π+ and quasiexclusive π- electroproduction were obtained from scattering of 1.6- to 5.7-GeV longitudinally polarized electrons from longitudinally polarized protons (for π+) and deuterons (for π-) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic range covered is 1.1 1.5 GeV. Very large target-spin asymmetries are observed for W >1.6 GeV. When combined with cross-section measurements, the present results can provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.3 GeV.

  5. Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1GeV2 . I. ep→eπ+n

    DOE PAGES

    Bosted, P. E.; Amaryan, M. J.; Anefalos Pereira, S.; ...

    2017-03-20

    Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π+ electroproduction reaction γ*p→nπ+. The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic range covered is 1.1 < W < 3 GeV and 1 < Q2 < 6GeV2. Results were obtained for about 6000 bins in W, Q2, cos(θ*), and Φ*. Except at forward angles, very large target-spin asymmetries are observed over the entire W region. Reasonable agreement is found with phenomenological fits to previous data for W < 1.6 GeV,more » but very large differences are seen at higher values of W. A generalized parton distributions (GPD)-based model is in poor agreement with the data. As a result, when combined with cross-sectional measurements, the present results provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.4 GeV.« less

  6. Target and beam-target spin asymmetries in exclusive π+ and π– electroproduction with 1.6- to 5.7-GeV electrons

    DOE PAGES

    Bosted, P. E.; Biselli, A. S.; Careccia, S.; ...

    2016-11-01

    Here, beam-target double-spin asymmetries and target single-spin asymmetries in exclusive π+ and quasiexclusive π– electroproduction were obtained from scattering of 1.6- to 5.7-GeV longitudinally polarized electrons from longitudinally polarized protons (for π+) and deuterons (for π–) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic range covered is 1.1 < W < 2.6 GeV and 0.05 < Q2 < 5GeV2, with good angular coverage in the forward hemisphere. The asymmetry results were divided into approximately 40 000 kinematic bins for π+ from free protons and 15 000 bins for π– production from bound nucleons in the deuteron.more » The present results are found to be in reasonable agreement with fits to previous world data for W < 1.7 GeV and Q2 < 0.5GeV2, with discrepancies increasing at higher values of Q2, especially for W > 1.5 GeV. Very large target-spin asymmetries are observed for W > 1.6 GeV. When combined with cross-section measurements, the present results can provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.3 GeV.« less

  7. Separated response functions in exclusive, forward π± electroproduction on deuterium

    SciTech Connect

    Huber, G. M.; Blok, H. P.; Butuceanu, C.; Gaskell, D.; Horn, T.; Mack, D. J.; Abbott, D.; Aniol, K.; Anklin, H.; Armstrong, C.; Arrington, J.; Assamagan, K.; Avery, S.; Baker, O. K.; Barrett, B.; Beise, E. J.; Bochna, C.; Boeglin, W.; Brash, E. J.; Breuer, H.; Chang, C. C.; Chant, N.; Christy, M. E.; Dunne, J.; Eden, T.; Ent, R.; Fenker, H.; Gibson, E. F.; Gilman, R.; Gustafsson, K.; Hinton, W.; Holt, R. J.; Jackson, H.; Jin, S.; Jones, M. K.; Keppel, C. E.; Kim, P. H.; Kim, W.; King, P. M.; Klein, A.; Koltenuk, D.; Kovaltchouk, V.; Liang, M.; Liu, J.; Lolos, G. J.; Lung, A.; Margaziotis, D. J.; Markowitz, P.; Matsumura, A.; McKee, D.; Meekins, D.; Mitchell, J.; Miyoshi, T.; Mkrtchyan, H.; Mueller, B.; Niculescu, G.; Niculescu, I.; Okayasu, Y.; Pentchev, L.; Perdrisat, C.; Pitz, D.; Potterveld, D.; Punjabi, V.; Qin, L. M.; Reimer, P. E.; Reinhold, J.; Roche, J.; Roos, P. G.; Sarty, A.; Shin, I. K.; Smith, G. R.; Stepanyan, S.; Tang, L. G.; Tadevosyan, V.; Tvaskis, V.; van der Meer, R. L. J.; Vansyoc, K.; Van Westrum, D.; Vidakovic, S.; Volmer, J.; Vulcan, W.; Warren, G.; Wood, S. A.; Xu, C.; Yan, C.; Zhao, W. -X.; Zheng, X.; Zihlmann, B.

    2015-01-07

    Background: Measurements of forward exclusive meson production at different squared four-momenta of the exchanged virtual photon, Q2, and at different four-momentum transfer, t, can be used to probe QCD's transition from meson-nucleon degrees of freedom at long distances to quark-gluon degrees of freedom at short scales. Ratios of separated response functions in π⁻ and π⁺ electroproduction are particularly informative. Ratio for transverse photons may allow this transition to be more easily observed, while the ratio for longitudinal photons provides a crucial verification of the assumed pole dominance, needed for reliable extraction of the pion form factor from electroproduction data. Method: Data were acquired with 2.6-5.2 GeV electron beams and the HMS+SOS spectrometers in Jefferson Lab Hall C, at central Q2 values of 0.6, 1.0, 1.6 GeV2 at W=1.95 GeV, and Q2=2.45 GeV2 at W=2.22 GeV. There was significant coverage in Φ And ϵ, which allowed separation of σL,T,LT,TT. Results: σL shows a clear signature of the pion pole, with a sharp rise at small -t. In contrast, σT is much flatter versus t. The longitudinal/transverse ratios evolve with Q2 and t, and at the highest Q2=2.45 GeV2 show a slight enhancement for π⁻ Production compared to π⁺. The π⁻/π⁺+ ratio for transverse photons exhibits only a small Q2-dependence, following a nearly universal curve with t, with a steep transition to a value of about 0.25, consistent with s-channel quark knockout. The σTTT ratio also drops rapidly with Q2, qualitatively consistent with s-channel helicity conservation. The π⁻/π⁺ ratio for longitudinal photons indicates a small isoscalar contamination at W=1.95 GeV, consistent with what was observed in our earlier determination of the pion form factor at these kinematics.

  8. Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1 GeV2. II. e p →e π0p

    NASA Astrophysics Data System (ADS)

    Bosted, P. E.; Kim, A.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Avakian, H.; Badui, R. A.; Ball, J.; Balossino, I.; Battaglieri, M.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Bültmann, S.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; 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.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Fegan, S.; Fersch, R.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Ghandilyan, Y.; Gilfoyle, G. P.; Girod, F. X.; Glazier, D. I.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Guler, N.; Hakobyan, H.; Guo, L.; Hafidi, K.; Hakobyan, H.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Hollis, G.; Holtrop, M.; Hughes, S. M.; Ireland, D. G.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, W.; Klei, A.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; Mayer, M.; McCracken, M. E.; McKinnon, B.; Mineeva, T.; Mirazita, M.; Mokeev, V. I.; Montgomery, R. A.; Movsisyan, A.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Ni, A.; Niccolai, S.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Saini, M. S.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Stepanyan, S.; Stoler, P.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2017-03-01

    Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π0 electroproduction reaction γ*p →p π0 , expanding an analysis of the γ*p →n π+ reaction from the same experiment. The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic ranges covered are 1.1 electroproduction. Reasonable agreement is found with phenomenological fits to previous data for W <1.6 GeV, but significant differences are seen at higher W . When combined with cross-sectional measurements, as well as π+ observables, the present results will provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.4 GeV.

  9. Investigating of the exclusive reaction of π⁺π⁻ pair electroproduction on a proton bound in a deuteron

    SciTech Connect

    Skorodumina, Yu. A.; Golovach, Evgeny N.; Gothe, Ralf W.; Ishkhanov, Boris S.; Isupov, Evgeny L.; Mokeev, Viktor I.; Fedotov, Gleb V.

    2015-04-01

    Preliminary results from analyzing π⁺π⁻ pair electroproduction on a proton bound in a deuteron are presented. Procedures for considering the Fermi motion of the initial proton in the deuteron and assessing the effects of interaction in the final states are developed. The yield of the reaction ep(n) → e'p'(n')π⁺π⁻ is obtained for the first time.

  10. Kaon electroproduction

    SciTech Connect

    Markowitz, P.

    1994-04-01

    The talk will focus on the physics which can be addressed by looking at semi-inclusive and exclusive channels in the DIS region. In particular, the author examines how this physics is reflected in the separated response functions.

  11. The space-time structure of hard scattering processes

    SciTech Connect

    J.-M. Laget

    2004-09-01

    Recent studies of exclusive electroproduction of vector mesons at JLab make it possible for the first time to play with two independent hard scales: the virtuality Q{sup 2}2 of the photon, which sets the observation scale, and the momentum transfer t to the hadronic system, which sets the interaction scale. They reinforce the description of hard scattering processes in terms of few effective degrees of freedom relevant to the Jlab-Hermes energy range.

  12. Imaging the proton via hard exclusive production in diffractive pp scattering

    SciTech Connect

    Charles Hyde; Leonid Frankfurt; Mark Strikman; Christian Weiss

    2007-05-21

    We discuss the prospects for probing Generalized Parton Distributions (GPDs) via exclusive production of a high-mass system (H = heavy quarkonium, di-photon, di-jet, Higgs boson) in diffractive pp scattering, pp -> p + H + p. In such processes the interplay of hard and soft interactions gives rise to a diffraction pattern in the final-state proton transverse momenta, which is sensitive to the transverse spatial distribution of partons in the colliding protons. We comment on the plans for diffractive pp measurements at RHIC and LHC. Such studies could complement future measurements of GPDs in hard exclusive ep scattering (JLab, COMPASS, EIC).

  13. Kaon Electroproduction on Deuterium

    SciTech Connect

    David Abbott; Abdellah Ahmidouch, Pawel Ambrozewicz; Chris Armstrong; John Arrington; K. Assamagan; Kevin Bailey; Oliver K. Baker; Shelton Beedoe; Elizabeth Beise; Herbert Breuer; Roger Carlini; Jinseok Cha; G. Collins; C. Cothran; W.J. Cummings; Samuel Danagoulian; Fraser Duncan; Jim Dunne; Dipangkar Dutta; Tom Eden; Rolf Ent; Lars Ewell; H.T. Fortune; Haiyan Gao; Donald Geesaman; Kenneth Gustafsson; Paul Gueye; Jens-Ole Hansen; Wendy Hinton; Hal Jackson; Cynthia Keppel; Andi Klein; D. Koltenok; David Mack; Richard Madey; Pete Markowitz; C.J. Martoff; David Meekins; Joseph Mitchell; R. Mohring; Hamlet Mkrtchyan; S.K. Mtingwa; Tom O'Neill; Gabriel Niculescu; Ioana Niculescu; Dave Potterveld; John Price; Philip Roos; Brian Raue; J.J. Reidy; Juerg Reinhold; G. Savage; Reyad Sawafta; J.P. Schiffer; Ralph Segel; Stepan Stepanyan; V. Tadevosian; Liguang Tang; B. Terburg; Stephen Wood; Chen Yan; Ben Zeidman; Beni Zihlmann

    1998-08-01

    Kaon electroproduction on deuterium and hydrogen targets has been measured at beam energies of 3.245 and 2.445GeV and momentum transfer Q{sup 2}=0.38 and O.5(GeV/c ){sup 2} Associated production off a proton in the deuteron exhibits a quasifree production mechanism. The electroproduction of a Sigma - off the neutron could be extracted for the first time with reasonable errors.

  14. Target and beam-target spin asymmetries in exclusive pion electroproduction for Q2>1 GeV2 . I. e p →e π+n

    NASA Astrophysics Data System (ADS)

    Bosted, P. E.; Amaryan, M. J.; Anefalos Pereira, S.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; De Vita, R.; Deur, A.; De Sanctis, E.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Elouadrhiri, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Forest, T.; Fradi, A.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guidal, M.; Hakobyan, H.; Hattawy, M.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, F. J.; Koirala, S.; Kubarovsky, V.; Kuhn, S. E.; Lanza, L.; Net, L. A.; Lenisa, P.; Livingston, K.; MacGregor, I. J. D.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Mirazita, M.; Mokeev, V. I.; Montgomery, R. A.; Munevar, E.; Munoz Camacho, C.; Murdoch, G.; Nadel-Turonski, P.; Niccolai, S.; Osipenko, M.; Ostrovidov, A. I.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Prok, Y.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rosner, G.; Rossi, P.; Schumacher, R. A.; Seder, E.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stankovic, I.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Wei, X.; Weinstein, L. B.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2017-03-01

    Beam-target double-spin asymmetries and target single-spin asymmetries were measured for the exclusive π+ electroproduction reaction γ*p →n π+ . The results were obtained from scattering of 6-GeV longitudinally polarized electrons off longitudinally polarized protons using the CEBAF Large Acceptance Spectrometer at Jefferson Laboratory. The kinematic range covered is 1.1

  15. Meson Form Factors and Deep Exclusive Meson Production Experiments

    NASA Astrophysics Data System (ADS)

    Horn, Tanja

    2017-03-01

    Pion and kaon electroproduction data play a unique role in Nature and our understanding of them is essential for explaining hadron structure. Precision longitudinaltransverse separated pion and kaon cross sections are of particular interest. They allow for the extraction of meson form factors and validation of understanding of hard exclusive and semi-inclusive reactions (π+, K+, π0, γ) towards 3D hadron imaging and potential future flavor decomposition. We review recent data and present prospects for deep exclusive pion and kaon electroproduction at the 12 GeV Jefferson Lab including the prospects to use projected charged- and neutral pion data to further determine the spin, charge-parity and flavor of GPDs, including the helicity-flip GPDs.

  16. Studies of semi-inclusive and hard exclusive processes at Jlab

    SciTech Connect

    Harutyun Avagyan

    2008-06-19

    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}.

  17. New results from the studies of the Ν (1440) 1/2+, Ν (1520) 3/2–, and Δ (1620) 1/2– resonances in exclusive ep → e'p'π+π– electroproduction with the CLAS detector

    DOE PAGES

    Mokeev, Viktor I.; Burkert, Volker D.; Carman, Daniel S.; ...

    2016-02-25

    In this study, the transition helicity amplitudes from the proton ground state to the N(1440)1/2+, N(1520)3/2–, and Δ(1620)1/2– resonances (γvpN* electrocouplings) were determined from the analysis of nine independent onefold differential π+π–p electroproduction cross sections off a proton target, taken with CLAS at photon virtualities 0.5GeV2 < Q2 < 1.5 GeV2. The phenomenological reaction model employed for separation of the resonant and nonresonant contributions to this exclusive channel was further developed.

  18. Measurement of the N --> Delta^+ (1232) Transition at High-Momentum Transfer by pi^0 Electroproduction

    SciTech Connect

    M. Ungaro; P. Stoler; I. Aznauryan; V. D. Burkert; K. Joo; L. C. Smith; G. Adams; M. Amarian; P. Ambrozewicz; M. Anghinolfi; G. Asryan; G. Audit; H. Avakian; H. Bagdasaryan; J. P. Ball; N. A. Baltzell; S. Barrow; V. Batourine; M. Battaglieri; I. Bedliski; M. Bektasoglu; M. Bellis; N. Benmouna; B. L. Berman; A. S. Biselli; B. E. Bonner; S. Bouchigny; S. Boiarinov; R. Bradford; D. Branford; W. J. Briscoe; W. K. Brooks; S. Bültmann; C. Butuceanu; J. R. Calarco; S. L. Careccia; D. S. Carman; A. Cazes; S. Chen; P. L. Cole; P. Coltharp; D. Cords; P. Corvisiero; D. Crabb; J. P. Cummings; E. De Sanctis; R. DeVita; P. V. Degtyarenko; H. Denizli; L. Dennis; A. Deur; K. V. Dharmawardane; C. Djalali; G. E. Dodge; J. Donnelly; D. Doughty; M. Dugger; S. Dytman; O. P. Dzyubak; H. Egiyan; K. S. Egiyan; L. Elouadrhiri; P. Eugenio; R. Fatemi; G. Fedotov; G. Feldman; R. J. Feuerbach; H. Funsten; M. Garçon; G. Gavalian; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; J. Goetz; C. I. O. Gordon; R. W. Gothe; K. A. Griffioen; M. Guidal; M. Guillo; N. Guler; L. Guo; V. Gyurjyan; C. Hadjidakis; R. S. Hakobyan; J. Hardie; D. Heddle; F. W. Hersman; I. Hleiqawi; M. Holtrop; K. Hicks; C. E. Hyde-Wright; Y. Ilieva; D. G. Ireland; B. S. Ishkhanov; M. M. Ito; D. Jenkins; H. S. Jo; H. G. Juengst; J. D. Kellie; M. Khandaker; W. Kim; A. Klein; F. J. Klein; A. V. Klimenko; M. Kossov; L. H. Kramer; V. Kubarovsky; J. Kuhn; S. E. Kuhn; J. Lachniet; J. M. Laget; J. Langheinrich; D. Lawrence; T. Lee; Ji Li; K. Livingston; C. Marchand; N. Markov; S. McAleer; B. McKinnon; J. W. C. McNabb; B. A. Mecking; S. Mehrabyan; J. J. Melone; M. D. Mestayer; C. A. Meyer; K. Mikhailov; R. Minehart; M. Mirazita; R. Miskimen; V. Mokeev; L. Morand; S. A. Morrow; J. Mueller; G. S. Mutchler; J. Napolitano; R. Nasseripour; S. Niccolai; G. Niculescu; I. Niculescu; B. B. Niczyporuk; M. Niroula; R. A. Niyazov; M. Nozar; G. V. O'Rielly; M. Osipenko; A. I. Ostrovidov; K. Park; E. Pasyuk; S. A. Philips; N. Pivnyuk; D. Pocanic; O. Pogorelko; E. Polli; S. Pozdniakov; B. M. Preedom; J. W. Price; Y. Prok; D. Protopopescu; L. M. Qin; B. A. Raue; G. Riccardi; G. Ricco; M. Ripani; B. G. Ritchie; F. Ronchetti; G. Rosner; P. Rossi; P. D. Rubin; F. Sabatié; C. Salgado; J. P. Santoro; V. Sapunenko; R. A. Schumacher; V. S. Serov; Y. G. Sharabian; A. V. Skabelin; E. S. Smith; D. I. Sober; A. Stavinsky; S. S. Stepanyan; S. Stepanyan; B. E. Stokes; I. I. Strakovsky; S. Strauch; M. Taiuti; D. J. Tedeschi; U. Thoma; A. Tkabladze; L. Todor; S. Tkachenko; C. Tur; M. F. Vineyard; A. V. Vlassov; L. B. Weinstein; D. P. Weygand; M. Williams; E. Wolin; M. H. Wood; A. Yegneswaran; L. Zana; B. Zhang; J. Zhang; and B. Zhao

    2006-09-01

    We report a new measurement of the exclusive electroproduction reaction gamma*_p --> pi0_p to explore the evolution from soft nonperturbative physics to hard processes via the Q2 dependence of the magnetic (M1+), electric (E1+), and scalar (S1+) multipoles in the N --> Delta transition. 9000 differential cross section data points cover W from threshold to 1.4 GeV/c2, 4pi center-of-mass solid angle, and Q2 from 3 to 6 GeV2/c2, the highest yet achieved. It is found that the magnetic form factor G^*M decreases with Q2 more steeply than the proton magnetic form factor, the ratio E1+/M1+ is small and negative, indicating strong helicity nonconservation, and the ratio S1+/M1+ is negative, while its magnitude increases with Q2.

  19. Electroproduction of Strange Nuclei

    SciTech Connect

    E.V. Hungerford

    2002-06-01

    The advent of high-energy, CW-beams of electrons now allows electro-production and precision studies of nuclei containing hyperons. Previously, the injection of strangeness into a nucleus was accomplished using secondary beams of mesons, where beam quality and target thickness limited the missing mass resolution. We review here the theoretical description of the (e, e'K+) reaction mechanism, and discuss the first experiment demonstrating that this reaction can be used to precisely study the spectra of light hypernuclei. Future experiments based on similar techniques, are expected to attain even better resolutions and rates.

  20. Deeply Pseudoscalar Meson Electroproduction with CLAS and Generalized Parton Distributions

    SciTech Connect

    Guidal, Michel; Kubarovsky, Valery P.

    2015-06-01

    We discuss the recent data of exclusive $\\pi^0$ (and $\\pi^+$) electroproduction on the proton obtained by the CLAS collaboration at Jefferson Lab. It is observed that the cross sections, which have been decomposed in $\\sigma_T+\\epsilon\\sigma_L$, $\\sigma_{TT}$ and $\\sigma_{LT}$ structure functions, are dominated by transverse amplitude contributions. The data can be interpreted in the Generalized Parton Distribution formalism provided that one includes helicity-flip transversity GPDs.

  1. New results from the studies of the Ν (1440) 1/2+, Ν (1520) 3/2, and Δ (1620) 1/2 resonances in exclusive ep → e'p'π+π electroproduction with the CLAS detector

    SciTech Connect

    Mokeev, Viktor I.; Burkert, Volker D.; Carman, Daniel S.; Elouadrhiri, Latifa; Fedotov, Gleb V.; Golovatch, Evgeny N.; Gothe, Ralf W.; Hicks, Ken; Ishkhanov, Boris S.; Isupov, Evgeny L.; Skorodumina, Iuliia

    2016-02-25

    In this study, the transition helicity amplitudes from the proton ground state to the N(1440)1/2+, N(1520)3/2, and Δ(1620)1/2 resonances (γvpN* electrocouplings) were determined from the analysis of nine independent onefold differential π+πp electroproduction cross sections off a proton target, taken with CLAS at photon virtualities 0.5GeV2 < Q2 < 1.5 GeV2. The phenomenological reaction model employed for separation of the resonant and nonresonant contributions to this exclusive channel was further developed.

  2. Electroproduction of the {Delta}(1232) Resonance at High Momentum Transfer

    SciTech Connect

    Frolov, V.V.; Adams, G.S.; Davidson, R.M.; Klusman, M.; Mukhopadhyay, N.C.; Napolitano, J.; Nozar, M.; Price, J.W.; Stoler, P.; Witkowski, M.; Bosted, P.; Armstrong, C.S.; Meekins, D.; Assamagan, K.; Avery, S.; Baker, O.K.; Eden, T.; Gaskell, D.; Gueye, P.; Hinton, W.; Keppel, C.; Madey, R.; Niculescu, G.; Niculescu, I.; Tang, L.; Ahmidouch, A.; Madey, R.; Kim, W.; Baker, O.K.; Burkert, V.; Carlini, R.; Dunne, J.; Ent, R.; Keppel, C.; Mack, D.; Mitchell, J.; Tang, L.; Wood, S.; Koltenuk, D.; Minehart, R.; Mkrtchyan, H.; Tadevosian, V.

    1999-01-01

    We studied the electroproduction of the {Delta}(1232) resonance via the reaction p(e,thinspe{sup {prime}}p){pi}{sup 0} at four-momentum transfers Q{sup 2}=2.8 and 4.0 GeV{sup 2} . This is the highest Q{sup 2} for which exclusive resonance electroproduction has ever been observed. Decay angular distributions for {Delta}{r_arrow}p{pi}{sup 0} were measured over a wide range of barycentric energies covering the resonance. The N{endash}{Delta} transition form factor G{sup {asterisk}}{sub M} and ratios of resonant multipoles E{sub 1+}/M{sub 1+} and S{sub 1+}/M{sub 1+} were extracted from the decay angular distributions. These ratios remain small, indicating that perturbative QCD is not applicable for this reaction at these momentum transfers. {copyright} {ital 1998} {ital The American Physical Society }

  3. Electroproduction of the Delta(1232) Resonance at High Momentum Transfer

    SciTech Connect

    Valera Frolov; Gary Adams; Abdellah Ahmidouch; Christopher Armstrong; Ketevi Assamagan; Steven Avery; O. Baker; Peter Bosted; Volker Burkert; Roger Carlini; R.M. Davidson; James Dunne; T. Eden; Rolf Ent; David Gaskell; Paul Gueye; Wendy Hinton; Cynthia Keppel; Wooyoung Kim; Mike Klusman; Douglas Koltenuk; David Mack; Richard Madey; David Meekins; Ralph Minehart; Joseph Mitchell; Hamlet Mkrtchyan; N.C.A Mukhopadhyay; James Napolitano; Gabriel Niculescu; Maria-Ioana Niculescu; Mina Nozar; John Price; Paul Stoler; Vardan Tadevosyan; Liguang Tang; Michael Witkowski; Stephen Wood

    1999-01-04

    Jefferson Lab experiment E94-014 measured the excitation of the Delta (1232) resonance via the reaction p(e,e{prime}p){pi}{sup 0} at Q{sup 2} near 2.8 and 4 Gev{sup 2}. This is the highest Q{sup 2} for which exclusive resonance electroproduction has ever been observed. Decay distributions of the Delta (1232) resonance into the ppi{sup 0} final state were measured over a wide range of barycentric decay angles and energies. The goal of this experiment is to assess the transition in Q{sup 2} from the constituent quark model (CQM) to the regime where hard processes become important. At Q{sup 2} {approx} few GeV{sup 2}/c{sup 2} the ratio E{sub 1+}/M{sub 1+} depends dramatically on the theoretical description, varying from a few 10{sup -2} in the CQM limit, to about 1 in the pQCD limit. Preliminary analysis of the data shows that the ratio E{sub 1+}/M{sub 1+} remains small at Q{sup 2} up to 4 Gev{sup 2}/c{sup 2}. After first pass analysis we obtain E{sub 1+}/M{sub 1+} = -4.1 {+-} 1.2 at Q{sup 2} = 2.8 Gev{sup 2}/c{sup 2} and E{sub 1+}/M{sub 1+} = -7.9 {+-} 0.8 at Q{sup 2} = 4 Gev{sup 2}/c{sup 2} (statistical errors only).

  4. Electroproduction in the Target Fragmentation Region

    NASA Astrophysics Data System (ADS)

    Avagyan, Harut

    2014-09-01

    The Semi-Inclusive DIS process in the Target Fragmentation Region (TFR), when the hadron is produced in the fragmentation process of the target remnants, can be described through the so-called Fracture Functions (FFs). They represent the joint probability of producing the final hadron from the target remnants, when a parton of the target nucleon is struck by the virtual photon in a hard scattering process. Like the ordinary parton distribution functions, the FFs are universal objects, thus they can be measured in one experiment at a given hard scale and then used to make predictions for other experiments, at another hard scale. Measurements of the Lambda multiplicities and polarization asymmetries in TFR, in particular, will provide information on corresponding Fracture Functions. The study of its Q2 dependence at JLab and EIC also will test the perturbative framework implied by Fracture Functions, simultaneously encoding the information on the interacting parton and on the fragmentation of the spectator system. We will present ongoing studies of electroproduction in TFR at Jefferson Lab, and proposed future measurement at upgraded JLab and Electron Ion Collider.

  5. Studies of N* Structure from the CLAS Meson Electroproduction Data

    SciTech Connect

    Mokeev, Viktor I.; Aznauryan, Inna G.

    2014-01-01

    The transition {gamma}{sub v}pN amplitudes (electrocouplings) for prominent excited nucleon states obtained in a wide area of photon virtualities offer valuable information for the exploration of the N 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 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 structure is discussed.

  6. Exclusive Reactions at High Momentum Transfer

    NASA Astrophysics Data System (ADS)

    Radyushkin, Anatoly; Stoler, Paul

    2008-03-01

    Hard exclusive scattering at JLab / P. Kroll -- AdS/CFT and exclusive processes in QCD / S. J. Brodsky and G. F. de Téramond -- Hadron structure matters in collisions at high energy and momentum / A. W. Thomas -- Inclusive perspectives / P. Hoyer -- Fitting DVCS at NLO and beyond / K. Kumericki, D. Müller and K. Passek-Kumericki -- Spin-orbit correlations and single-spin asymmetries / M. Burkardt -- Electroproduction of soft pions at large momentum transfers / V. M. Braun, D. Yu. Ivanov and A. Peters -- Color transparency: 33 years and still running / M. Strikman -- Meson clouds and nucleon electromagnetic form factors / G. A. Miller -- Covariance, dynamics and symmetries, and hadron form factors / M. S. Bhagwat, I. C. Cloët and C. D. Roberts -- N to [symbol] electromagnetic and axial form factors in full QCD / C. Alexandrou -- Real and virtual compton scattering in perturbative QCD / C.-R. Ji and R. Thomson -- Deeply virtual compton scattering at Jefferson Lab / F. Sabatie -- DVCS at HERMES: recent results / F. Ellinghaus -- Deeply virtual compton scattering with CLAS / F. X. Girod -- Deeply virtual compton scattering off the neutron at JLab Hall A / M. Mazouz -- The future DVCS experiments in Hall A at JLab / J. Roche -- Deeply virtual compton scattering with CLAS12 / L. Elouadrhiri -- Quark helicity flip and the transverse spin dependence of inclusive DIS / A. Afanasev, M. Strikman and C. Weiss -- Deeply virtual pseudoscalar meson production / V. Kubarovsky and P. Stoler -- Exclusive p[symbol] electroproduction on the proton: GPDs or not GPDs? / M. Guidal and S. Morrow -- p[symbol] transverse target spin asymmetry at HERMES / A. Airapetian -- Electroproduction of ø(1020) mesons / J. P. Santoro and E. S. Smith -- Generalized parton distributions from hadronic observables / S. Ahmad ... [et al.] -- Imaging the proton via hard exclusive production in diffractive pp scattering / G. E. Hyde ... [et al.] -- Regge contributions to exclusive electro-production / A

  7. Vector meson electroproduction in QCD

    NASA Astrophysics Data System (ADS)

    Lu, Juan; Cai, Xian-Hao; Zhou, Li-Juan

    2012-08-01

    Based on the generalized QCD vector meson dominance model, we study the electroproduction of a vector meson off a proton in the QCD inspired eikonalized model. Numerical calculations for the total cross section σtot and differential cross section dσ/dt are performed for ρ, ω and varphi meson electroproduction in this paper. Since gluons interact among themselves (self-interaction), two gluons can form a glueball with quantum numbers IG, JPC = 0+,2++, decay width Γt ≈ 100 MeV, and mass of mG = 2.23 GeV. The three gluons can form a three-gluon colorless bound state with charge conjugation quantum number C = -1, called the Odderon. The mediators of interactions between projectiles (the quark and antiquark pair fluctuated from the virtual photon) and the proton target (a three-quark system) are the tensor glueball and the Odderon. Our calculated results in the tensor glueball and Odderon exchange model fit to the existing data successfully, which evidently shows that our present QCD mechanism is a good description of meson electroproduction off a proton. It should be emphasized that our mechanism is different from the theoretical framework of Block et al. We also believe that the present study and its success are important for the investigation of other vector meson electro- and photoproduction at high energies, as well as for searching for new particles such as tensor glueballs and Odderons, which have been predicted by QCD and the color glass condensate model (CGC). Therefore, in return, it can test the validity of QCD and the CGC model.

  8. Electroproduction of baryon-meson states and strangeness suppression

    NASA Astrophysics Data System (ADS)

    Santopinto, E.; García-Tecocoatzi, H.; Bijker, R.

    2016-08-01

    We describe the electroproduction ratios of baryon-meson states from nucleon, inferring from the sea quarks in the nucleon using an extension of the quark model that takes into account the sea. As a result we provide, with no adjustable parameters, the predictions of ratios of exclusive meson-baryon final states: ΛK+, Σ* K, ΣK, pπ0, and nπ+. These predictions are in agreement with the new JLab experimental data showing that sea quarks play an important role in the electroproduction. We also predicted further ratios of exclusive reactions that can be measured and tested in future experiments. In particular, we suggested new experiments on deuterium and tritium. Such measurements can provide crucial tests of different predictions concerning the structure of nucleon and its sea quarks helping to solve an outstanding problem. Finally, we compute the so called strangeness suppression factor, λs, that is the suppression of strange quark-antiquark pairs compared to nonstrange pairs, and we found that our finding with this simple extension of the quark model is in good agreement with the results of JLab and CERN experiments.

  9. Neutral Pion Electroproduction in the Δ Resonance Region

    SciTech Connect

    Villano, Anthony

    2007-11-01

    The electroproduction of baryon resonances at high Q2 is examined. Analysis focuses on the Δ(1232) resonance via exclusive pseudoscalar meson production of π0 particles. Differential cross sections are extracted for exclusive π0 electroproduction. In the central invariant mass (W) region the cross sections are used to extract resonant multipole amplitudes. In particular, the ratio of the electric quadrupole to magnetic dipole amplitudes (E2/M1) will be discussed for the Δ(1232) resonance. The transition to pQCD is discussed in terms of E2/M1 and other multipoles. The helicity amplitude A3/2 can be used as a baryon helicity conservation meter in this context and will be discussed. The fast shrinking of the resonant contribution in the Δ region is observed at this high momentum transfer. Apart from the observables related to pQCD scaling, the transition form factor G$*\\atop{M}$ is extracted along with the scalar to magnetic dipole ratio C2/M1.

  10. Target and beam-target spin asymmetries in exclusive π+ and π electroproduction with 1.6- to 5.7-GeV electrons

    SciTech Connect

    Bosted, P. E.; Biselli, A. S.; Careccia, S.; Dodge, G.; Fersch, R.; Guler, N.; Kuhn, S. E.; Pierce, J.; Prok, Y.; Zheng, X.; Adhikari, K. P.; Adikaram, D.; Akbar, Z.; Amaryan, M. J.; Anefalos Pereira, S.; Asryan, G.; Avakian, H.; Badui, R. A.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Boiarinov, S.; Briscoe, W. J.; Bültmann, S.; Burkert, V. D.; Cao, T.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Chetry, T.; Ciullo, G.; Clark, L.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; Deur, A.; Djalali, C.; Dupre, R.; Egiyan, H.; El Alaoui, A.; El Fassi, L.; Eugenio, P.; Fanchini, E.; Fedotov, G.; Filippi, A.; Fleming, J. A.; Forest, T. A.; Fradi, A.; Garçon, M.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Gleason, C.; Gohn, W.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guo, L.; Hafidi, K.; Hanretty, C.; Harrison, N.; Hattawy, M.; Heddle, D.; Hicks, K.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Isupov, E. L.; Jenkins, D.; Jiang, H.; Jo, H. S.; Joo, K.; Joosten, S.; Keller, D.; Khandaker, M.; Kim, W.; Klein, A.; Klein, F. J.; Kubarovsky, V.; Kuleshov, S. V.; Lanza, L.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Markov, N.; McCracken, M. E.; McKinnon, B.; Meyer, C. A.; Minehart, R.; Mirazita, M.; Mokeev, V.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Ni, A.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Paremuzyan, R.; Park, K.; Pasyuk, E.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schumacher, R. A.; Seder, E.; Sharabian, Y. G.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sparveris, N.; Stankovic, Ivana; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Taiuti, M.; Tian, Ye; Torayev, B.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2016-11-01

    Here, beam-target double-spin asymmetries and target single-spin asymmetries in exclusive π+ and quasiexclusive π electroproduction were obtained from scattering of 1.6- to 5.7-GeV longitudinally polarized electrons from longitudinally polarized protons (for π+) and deuterons (for π) using the CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab. The kinematic range covered is 1.1 < W < 2.6 GeV and 0.05 < Q2 < 5GeV2, with good angular coverage in the forward hemisphere. The asymmetry results were divided into approximately 40 000 kinematic bins for π+ from free protons and 15 000 bins for π production from bound nucleons in the deuteron. The present results are found to be in reasonable agreement with fits to previous world data for W < 1.7 GeV and Q2 < 0.5GeV2, with discrepancies increasing at higher values of Q2, especially for W > 1.5 GeV. Very large target-spin asymmetries are observed for W > 1.6 GeV. When combined with cross-section measurements, the present results can provide powerful constraints on nucleon resonance amplitudes at moderate and large values of Q2, for resonances with masses as high as 2.3 GeV.

  11. Measurement of the N ---> Delta+(1232) transition at high momentum transfer by pi0 electroproduction

    SciTech Connect

    M. Ungaro; K. Joo; P. Stoler

    2006-06-01

    The measurement of the differential cross section of the exclusive electroproduction reaction gamma*p --> pi^0p in W region of the Delta^+(1232) resonance is reported. The magnetic form factor (G*_M) and ratios of electric to magnetic and scaler to magnetic multipole amplitudes R_EM = E_1+/M_1+ and R_SM = S_1+/M_1+ for the gamma*p --> Delta+(1232) transition are extracted in the framework of a unitary isobar model.

  12. Electroproduction of pseudoscalar mesons above the resonance region

    SciTech Connect

    Niczyporuk, B.B.

    1994-04-01

    In this paper, the author has revisited twenty year old data considering the progress achieved in related fields. To make further progress in our understanding of strong interactions, one needs much better quality of exclusive electroproduction data. A measurement of the differential cross section {sigma}(t, W, Q{sup 2}) for the reactions e{sup {minus}} + p {r_arrow} e{sup {minus}} + {pi}{sup +}(K{sup +}) + n({Lambda}{degrees}) at a beam energy of {ge} 4 GeV is proposed. Data will be collected simultaneously for both reactions using the CLAS detector at CEBAF in the following kinematical region: Q{sup 2} > 1 GeV{sup 2} and W > 2 GeV. One of the most interesting aspects of electroproduction is that it can be used to measure photoproduction amplitudes as functions of the photon mass squared Q{sup 2} and momentum transfer t. Emphasis is given to measuring the differential cross sections for t {approximately} m{sup 2}{sub {pi},{kappa}}. Above the resonance region (W > 2 GeV), the cross section is dominated by the amplitudes for scalar photons. Measured angular distributions of produced mesons will be used to estimate the contribution of various amplitudes to the cross sections. High statistics and good quality data collected simultaneously using a large acceptance detector will improve our understanding of nucleon structure as well as the hadronic properties of the photon.

  13. Nucleon Resonance Electrocouplings from the CLAS Meson Electroproduction Data.

    SciTech Connect

    Inna Aznauryan, Volker Burkert, Viktor Mokeev

    2012-04-01

    Transition helicity amplitudes {gamma}{sub {nu}}NN* (electrocouplings) were determined for prominent excited proton states with masses less than 1.8 GeV in independent analyses of major meson electroproduction channels: {pi}{sup +}n, {pi}{sup 0}p and {pi}{sup +}{pi}{sup -}p. Consistent results on resonance electrocouplings obtained from analyses of these exclusive reactions with very different non-resonant contributions demonstrated reliable extraction of these fundamental quantities for states that have significant decays for either N{pi} or N{pi}{pi} channels. Preliminary results on electrocouplings of N* states with masses above 1.6 GeV have become available from the CLAS data on {pi}{sup +}{pi}{sup -}p electroproduction off protons for the first time. Comparison with quark models and coupled channel approaches strongly suggest that N* structure is determined by contributions from an internal core of three constituent quarks and an external meson-baryon cloud at the distance scales covered in measurements with the CLAS detector.

  14. Spin Observables in Kaon Electroproduction

    SciTech Connect

    O.K. Baker

    1998-06-01

    The CEBAF accelerator at Jefferson Lab has proven to be a powerful tool for use in studying the electromagnetic production of hadronic systems containing a strange constituent quark. The electromagnetic probe only marginally disturbs the system being investigated, and is well understood. Its use as a means to probe the internal structure of hadronic systems has been well documented. Among the most studied of these hadronic systems, currently, is the nucleon. The unique opportunities afforded by the use of polarized, high-current, high-duty-factor electron beams provides an even more powerful probe of the electromagnetic structure of hadronic systems; the study of the spin dependence of the electromagnetic production and weak decay of the hyperon, specifically the {Lambda}-hyperon, becomes feasible. An experiment to study the electroproduction of the {Lambda} as a function of virtual photon momentum transfer, angle, and energy, using spin polarization observables in order to extract insights into its production and weak decay dynamics has already been approved at Jefferson Lab (E98-101; Spin Polarization in Kaon Electroproduction). The experiment aims to study the mechanism of polarization transfer in the reaction e + p {yields} e' + K + {Lambda}. The experiment requires only moderate momentum resolution and no specialized equipment other than that associated with the polarized beam. The data quality is expected to improve with higher electron beam energies, for higher Q{sup 2} measurements. Additionally, at higher energies the increased virtual photon flux allows the 4experiment to be run at lower currents (and therefore high beam polarization). A polarized electron beam and an unpolarized cryogenic hydrogen target are required. The study uses the electron arm spectrometer and the hadron arm spectrometer to detect the scattered electron and the electroproduced kaon before it decays in flight, respectively. Additionally, the hadron arm will be used to detect the

  15. Exclusive Neutral Pion Electroproduction in the Deeply Virtual Regime

    SciTech Connect

    Fuchey, E; Camsonne, A; Mazouz, M; Gavalian, G; Kuchina, E; Amarian, M; Aniol, K A; Beaumel, M; Benaoum, H; Bertin, P; Brossard, M; Canan, M; Chen, J -P; Chudakov, E; Craver, B; Cusanno, F; de Jager, C W; Deur, A; Ferdi, C; Feuerbach, R; Fieschi, J -M; Frullani, S; Garcon, M; Garibaldi, F; Gayou, O; Gilman, R; Gomez, J; Gueye, P; Guichon, P.A.M.; Guillon, B; Hansen, O; Hayes, D; Higinbotham, D W; Homstrom, T; Hyde, C E; Ibrahim, H; Igarashi, R; Itard, F; Jiang, X; Jo, H S; Kaufman, L J; Kelleher, A; Kolarkar, A; Kumbartzki, G; Laveissiere, G; LeRose, J J; Lindgren, R; Liyanage, N; Lu, H -J; Margaziotis, D J; Meziani, Z -E; McCormick, K; Michaels, R; Michel, B; Moffit, B; Monaghan, P; Nanda, S; Nelyubin, V; Potokar, M; Qiang, Y; Ransome, R D; Real, J -S; Reitz, B; Roblin, Y; Roche, J; Sabatie, F; Saha, A; Sirca, S; Slifer, K; Solvignon, P; Subedi, R; Sulkosky, V; Ulmer, P E; Voutier, E; Wang, K; Weinstein, L B; Wojtsekhowski, B; Zheng, X; Zhu, L

    2011-02-01

    We present measurements of the ep->ep pi^0 cross section extracted at two values of four-momentum transfer Q^2=1.9 GeV^2 and Q^2=2.3 GeV^2 at Jefferson Lab Hall A. The kinematic range allows to study the evolution of the extracted hadronic tensor as a function of Q^2 and W. Results will be confronted with Regge inspired calculations and GPD predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering has also been attempted.

  16. Exclusive neutral pion electroproduction in the deeply virtual regime

    SciTech Connect

    Fuchey, E.; Camsonne, A.; Bertin, P.; Munoz Camacho, C.; Gavalian, G.; Amarian, M.; Canan, M.; Hayes, D.; Ibrahim, H.; Ulmer, P. E.; Weinstein, L. B.; Kuchina, E.; Gilman, R.; Jiang, X.; Kumbartzki, G.; McCormick, K.; Ransome, R. D.; Aniol, K. A.; Margaziotis, D. J.

    2011-02-15

    We present measurements of the ep{yields}ep{pi}{sup 0} cross section extracted at two values of four-momentum transfer Q{sup 2}=1.9 GeV{sup 2} and Q{sup 2}=2.3 GeV{sup 2} at Jefferson Lab Hall A. The kinematic range allows one to study the evolution of the extracted cross section as a function of Q{sup 2} and W. Results are confronted with Regge-inspired calculations and GPD predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering is also discussed.

  17. Delta Electroproduction in 12-C

    SciTech Connect

    McLauchlan, Steven

    2003-01-01

    The Δ-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 Δ mass indicating that this potential is dependent on the momentum of the Δ. 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 Δ resonance in 12C, performed using the high energy electron beam at the Thomas Jefferson National Accelerator Facility, and the near 4π 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 Δ mass was only observed in the exclusive measurements indicating that the Δ-nucleus potential is affected by the momentum of the Δ.

  18. Unitary constraints on neutral pion electroproduction

    DOE PAGES

    Laget, J. -M.

    2010-11-10

    At large virtualitymore » $Q^2$, the coupling to the vector meson production channels provides us with a natural explanation of the surprisingly large cross section of the neutral pion electroproduction recently measured at Jefferson Laboratory, without destroying the good agreement between the Regge pole model and the data at the real photon point. Lastly, elastic rescattering of the $$\\pi^0$$ provides us with a way to explain why the node, that appears at $$t\\sim -0.5$$~GeV$^2$ at the real photon point, disappears as soon as $Q^2$ differs from zero.« less

  19. Generalized Parton Distributions and Deep Exclusive Reactions: Present Program at Jlab

    SciTech Connect

    Michel Garcon

    2004-07-01

    We review briefly the physical concept of generalized parton distributions and the experimental challenges associated with the corresponding measurements of deep exclusive reactions. The first data obtained at Jefferson Lab for exclusive photon (DVCS) and vector meson (DVMP) electroproduction above the resonance-excitation region are described. Two upcoming dedicated DVCS experiments are presented in some detail.

  20. Onset of quark-hadron duality in pion electroproduction.

    PubMed

    Navasardyan, T; Adams, G S; Ahmidouch, A; Angelescu, T; Arrington, J; Asaturyan, R; Baker, O K; Benmouna, N; Bertoncini, C; Blok, H P; Boeglin, W U; Bosted, P E; Breuer, H; Christy, M E; Connell, S H; Cui, Y; Dalton, M M; Danagoulian, S; Day, D; Dodario, T; Dunne, J A; Dutta, D; El Khayari, N; Ent, R; Fenker, H C; Frolov, V V; Gan, L; Gaskell, D; Hafidi, K; Hinton, W; Holt, R J; Horn, T; Huber, G M; Hungerford, E; Jiang, X; Jones, M; Joo, K; Kalantarians, N; Kelly, J J; Keppel, C E; Kubarovski, V; Li, Y; Liang, Y; Malace, S; Markowitz, P; McGrath, E; McKee, P; Meekins, D G; Mkrtchyan, H; Moziak, B; Niculescu, G; Niculescu, I; Opper, A K; Ostapenko, T; Reimer, P; Reinhold, J; Roche, J; Rock, S E; Schulte, E; Segbefia, E; Smith, C; Smith, G R; Stoler, P; Tadevosyan, V; Tang, L; Ungaro, M; Uzzle, A; Vidakovic, S; Villano, A; Vulcan, W F; Wang, M; Warren, G; Wesselmann, F; Wojtsekhowski, B; Wood, S A; Xu, C; Yuan, L; Zheng, X; Zhu, H

    2007-01-12

    A large data set of charged-pion (pi+/-) electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-->pion production mechanisms.

  1. The Onset of Quark-Hadron Duality in Pion Electroproduction

    SciTech Connect

    Tigran Navasardyan; Gary Adams; Abdellah Ahmidouch; Tatiana Angelescu; John Arrington; Razmik Asaturyan; O. Baker; Nawal Benmouna; Crystal Bertoncini; Henk Blok; Werner Boeglin; Peter Bosted; Herbert Breuer; Michael Christy; Simon Connell; Yonggang Cui; Mark Dalton; Samuel Danagoulian; Donal Day; T. Dodario; James Dunne; Dipangkar Dutta; Najib Elkhayari; Rolf Ent; Howard Fenker; Valera Frolov; Liping Gan; David Gaskell; Kawtar Hafidi; Wendy Hinton; Roy Holt; Tanja Horn; Garth Huber; Ed Hungerford; Xiaodong Jiang; Mark Jones; Kyungseon Joo; Narbe Kalantarians; James Kelly; Cynthia Keppel; Edward Kinney; V. Kubarovski; Ya Li; Yongguang Liang; Simona Malace; Pete Markowitz; Erin McGrath; Daniella Mckee; David Meekins; Hamlet Mkrtchyan; Brian Moziak; Gabriel Niculescu; Maria-Ioana Niculescu; Allena Opper; Tanya Ostapenko; Paul Reimer; Joerg Reinhold; Julie Roche; Stephen Rock; Elaine Schulte; Edwin Segbefia; C. Smith; G.R. Smith; Paul Stoler; Vardan Tadevosyan; Liguang Tang; Maurizio Ungaro; Alicia Uzzle; Sandra Vidakovic; Anthony Villano; William Vulcan; Miao Wang; Glen Warren; Frank Wesselmann; Bogdan Wojtsekhowski; Stephen Wood; Chuncheng Xu; Lulin Yuan; Xiaochao Zheng; Hong Guo Zhu

    2006-08-29

    A large data set of charged-pion electroproduction from both hydrogen and deuterium targets has been obtained spanning the low-energy residual-mass region. These data conclusively show the onset of the quark-hadron duality phenomenon, as predicted for high-energy hadron electroproduction. We construct several ratios from these data to exhibit the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark-to- pion production mechanisms.

  2. Electroproduction of kaons and light hypernuclei

    SciTech Connect

    Geesaman, D.F.; Jackson, H.E.; Jones, C.E.

    1995-08-01

    A detailed investigation of the basic hyperon-nucleon interactions in nuclei is one of the aims of Experiment 91-016, approved with high priority at CEBAF, to study the electroproduction of kaons on targets of deuterium, {sup 3}He, and {sup 4}He. Inasmuch as both the electron and K{sup +} are particles that interact relatively weakly with nucleons, electroproduction of light hypernuclei provides a low-distortion method for investigating the fundamental interactions between nucleons, {Alpha}`s, and {Epsilon}`s in few-body systems. In particular, the (e,e`K{sup +}) reactions on cryogenic targets of D, {sup 3}He, and {sup 4}He will be studied at incident electron energies near 3 GeV with coincident detection of the emergent e and K{sup +} in the HMS and SOS magnetic spectrometers in Hall C. Construction of the He target, operating at {approximately}10 atm, {approximately}50 K and capable of dissipating {approximately}30 W, is expected to be complete prior to commencement of production runs in Hall C. The first data runs for E91-016, expected to begin late in FY 1995, will also be the basis for a doctoral thesis at Hampton University. In addition to providing new information on the phases of hyperon-nucleon interactions, measurements of cross sections for hypernuclear formation, and interference phenomena, the data may provide evidence for the presence of bound {Epsilon}`s and strange di-baryonic states that are the subject of considerable theoretical discussion.

  3. Kaon electro-production on protons at JLab in Hall A

    SciTech Connect

    Mauro Iodice

    2003-07-15

    The elementary reaction of kaon exclusive electro-production on protons has been studied in a broad kinematical range at Jefferson Lab in Hall A. Data have been taken at different values of the invariant center-of-mass energy W in the range W=1.8-2.2 GeV, for two values of the transferred 4-momentum Q2 =1.9 and 2.4 (GeV/c)2. Each kinematics was measured at different electron beam energies so as to separate the longitudinal (L) and transverse (T) contributions to the cross-section. The LT interference term has also been measured for a limited number of kinematics. The preliminary data are compared to results of different models developed in the framework of hadronic field and Regge theories.

  4. Electroproduction of pions at threshold in chiral perturbation theory

    SciTech Connect

    Lee, T.S.H.; Bernard, V.; Kaiser, N.; Meissner, U.G.

    1995-08-01

    The electroproduction of pions off protons close to threshold is studied within the framework of baryon chiral perturbation theory. The approach is based on the fundamental QCD property that at low energies the strong interactions are dictated by the spontaneously broken chiral symmetry. The calculation was done up to the 1-loop level by carrying out order-by-order renormalization procedures. A thorough study of the low-energy theorems related to electroproduction of pions was carried out. Our study showed how the axial radius of the nucleon can be related to the S-wave multipoles E{sub 0+}{sup (-)} and L{sub 0+}{sup (-)}.

  5. Longitudinal Electroproduction of Charged Pions from

    SciTech Connect

    David Gaskell; Abdellah Ahmidouch; Pawel Ambrozewicz; H. Anklin; John Arrington; K. Assamagan; Steven Avery; Kevin Bailey; Oliver K. Baker; Shelton Beedoe; Elizabeth Beise; Herbert Breuer; D. S. Brown; Roger Carlini; Jinseok Cha; Nicholas Chant; Anthony Cowley; Samuel Danagoulian; D. De Schepper; Jim Dunne; Dipangkar Dutta; Rolf Ent; Liping Gan; Ashot Gasparian; Donald Geesaman; Ron Gilman; Charles Glashausser; Paul Gueye; M. Harvey; O. Hashimoto; Wendy Hinton; G. Hofman; Ceasar Jackson; Hal Jackson; Cynthia Keppel; Ed Kinney; Doug Koltenuk; G. Kyle; Allison Lung; David Mack; D. McKee; Joseph Mitchell; Hamlet Mkrtchyan; B. Mueller; Gabriel Niculescu; Ioana Niculescu; Tom O'Neill; V. Papavassiliou; Dave Potterveld; Juerg Reinhold; Philip Roos; Reyad Sawafta; Ralph Segel; Stepan Stepanyan; Vardan Tadevosyan; T. Takahashi; Liguang Tang; B. Terburg; D. Van Westrum; J. Volmer; T. P. Welch; Stephen Wood; Lulin Yuan; Ben Zeidman; Beni Zihlmann

    2001-11-12

    Separated longitudinal and transverse cross sections for charged pion electroproduction from {sup 1}H, {sup 2}H, and {sup 3}He were measured at Q{sup 2} = 0.4 (GeV/c){sup 2} for two values of the invariant mass, {bar W} = 1.15 GeV and {bar W} = 1.60 GeV, in a search for a mass dependence which would signal the effect of nuclear pions. This is the first such study that includes recoil momenta significantly above the Fermi surface. The longitudinal cross section, if dominated by the pion-pole process, should be sensitive to nuclear pion currents. Comparisons of the longitudinal cross section target ratios to a quasifree calculation reveal a significant suppression in {sup 3>}He at {bar W} = 1.60 GeV. The {bar W} = 1.15 GeV results are consistent with simple estimates of the effect of nuclear pion currents, but are also consistent with pure quasifree production.

  6. Spin O decay angular distribution for interfering mesons in electroproduction

    SciTech Connect

    Funsten, H.; Gilfoyle, G.

    1994-04-01

    Self analyzing meson electroproduction experiments are currently being planned for the CEBAF CLAS detector. These experiments deduce the spin polarization of outgoing unstable spin s (?)0 mesons from their decay angular distribution, W({theta},{psi}). The large angular acceptance of the CLAS detector permits kinematic tracking of a sufficient number of these events to accurately determine electroproduction amplitudes from the deduced polarization. Maximum polarization information is obtained from W({theta},{psi}) for decay into spin 0 daughters. The helicity of the decaying meson is transferred to the daughter`s relative orbital angular momentum m-projection; none is {open_quotes}absorbed{close_quotes} into daughter helicities. The decaying meson`s helicity maximally appears in W({theta},{psi}). W({theta},{psi}) for spin 0 daughters has been derived for (1) vector meson electroproduction and (2) general interfering mesons produced by incident pions. This paper derives W({theta},{psi}) for electroproduction of two interfering mesons that decay into spin 0 daughters. An application is made to the case of interfering scalar and vector mesons. The derivation is an extension of work by Schil using the general decay formalism of Martin. The expressions can be easily extended to the case of N interfering mesons since interference occurs pairwise in the observable W ({theta},{psi}), a quadratic function of the meson amplitudes. The derivation uses the virtual photon density matrix of Schil which is transformed by a meson electroproduction transition operator, T. The resulting density matrix for the interfering mesons is then converted into a corresponding statistical tensor and contracted into the efficiency tensor for spin 0 daughters.

  7. Deeply Virtual Exclusive Reactions with CLAS

    SciTech Connect

    Kubarovsky, Valery

    2011-03-01

    Deeply virtual exclusive reactions offer an unique opportunity to study the structure of the nucleon at the parton level as one has access to Bjorken xB and momentum transfer to the nucleon t at the same time. Such processes can reveal much more information about the structure of the nucleon than either inclusive electroproduction or elastic form factors alone. Dedicated experiments to study Deeply Virtual Compton Scattering (DVCS) and Deeply VirtualMeson Production (DVMP) have been carried out in Hall B at Jefferson Lab. DVCS helicity–dependent and helicity–independent cross sections and beam spin asymmetries have been measured with CLAS, as well as cross sections and asymmetries for the p 0, h, r 0, r+, w and f for exclusive electroproduction. The data were taken in a wide kinematic range in Q2=1–4.5 GeV2, xB=0.1–0.5, and |t| up to 2 GeV2. We will discuss the interpretation of these data in terms of traditional Regge and Generalized Parton Distributions models. We view the work presented in this report as leading into the program of the Jefferson Lab 12 GeV upgrade. The increased energy and luminosity will allow us to acquire data at much higher Q2 and xB, and perform Rosenbluth L/T separations of the cross sections.

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

    SciTech Connect

    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

    2008-08-01

    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.

  9. Rosenbluth Separation of the π^{0} Electroproduction Cross Section.

    PubMed

    Defurne, M; Mazouz, M; Ahmed, Z; Albataineh, H; Allada, K; Aniol, K A; Bellini, V; Benali, M; Boeglin, W; Bertin, P; Brossard, M; Camsonne, A; Canan, M; Chandavar, S; Chen, C; Chen, J-P; de Jager, C W; de Leo, R; Desnault, C; Deur, A; El Fassi, L; Ent, R; Flay, D; Friend, M; Fuchey, E; Frullani, S; Garibaldi, F; Gaskell, D; Giusa, A; Glamazdin, O; Golge, S; Gomez, J; Hansen, O; Higinbotham, D; Holmstrom, T; Horn, T; Huang, J; Huang, M; Huber, G M; Hyde, C E; Iqbal, S; Itard, F; Kang, Ho; Kang, Hy; Kelleher, A; Keppel, C; Koirala, S; Korover, I; LeRose, J J; Lindgren, R; Long, E; Magne, M; Mammei, J; Margaziotis, D J; Markowitz, P; Martí Jiménez-Argüello, A; Meddi, F; Meekins, D; Michaels, R; Mihovilovic, M; Muangma, N; Muñoz Camacho, C; Nadel-Turonski, P; Nuruzzaman, N; Paremuzyan, R; Puckett, A; Punjabi, V; Qiang, Y; Rakhman, A; Rashad, M N H; Riordan, S; Roche, J; Russo, G; Sabatié, F; Saenboonruang, K; Saha, A; Sawatzky, B; Selvy, L; Shahinyan, A; Sirca, S; Solvignon, P; Sperduto, M L; Subedi, R; Sulkosky, V; Sutera, C; Tobias, W A; Urciuoli, G M; Wang, D; Wojtsekhowski, B; Yao, H; Ye, Z; Zana, L; Zhan, X; Zhang, J; Zhao, B; Zhao, Z; Zheng, X; Zhu, P

    2016-12-23

    We present deeply virtual π^{0} electroproduction cross-section measurements at x_{B}=0.36 and three different Q^{2} values ranging from 1.5 to 2  GeV^{2}, obtained from Jefferson Lab Hall A experiment E07-007. The Rosenbluth technique is used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component and, thus, is far from the asymptotic limit predicted by perturbative quantum chromodynamics. Nonetheless, an indication of a nonzero longitudinal contribution is provided by the measured interference term σ_{LT}. Results are compared with several models based on the leading-twist approach of generalized parton distributions (GPDs). In particular, a fair agreement is obtained with models in which the scattering amplitude includes convolution terms of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. This experiment, together with previous extensive unseparated measurements, provides strong support to the exciting idea that transversity GPDs can be accessed via neutral pion electroproduction in the high-Q^{2} regime.

  10. Rosenbluth Separation of the π0 Electroproduction Cross Section

    NASA Astrophysics Data System (ADS)

    Defurne, M.; Mazouz, M.; Ahmed, Z.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J.-P.; de Jager, C. W.; de Leo, R.; Desnault, C.; Deur, A.; El Fassi, L.; Ent, R.; Flay, D.; Friend, M.; Fuchey, E.; Frullani, S.; Garibaldi, F.; Gaskell, D.; Giusa, A.; Glamazdin, O.; Golge, S.; Gomez, J.; Hansen, O.; Higinbotham, D.; Holmstrom, T.; Horn, T.; Huang, J.; Huang, M.; Huber, G. M.; Hyde, C. E.; Iqbal, S.; Itard, F.; Kang, Ho.; Kang, Hy.; Kelleher, A.; Keppel, C.; Koirala, S.; Korover, I.; LeRose, J. J.; Lindgren, R.; Long, E.; Magne, M.; Mammei, J.; Margaziotis, D. J.; Markowitz, P.; Martí Jiménez-Argüello, A.; Meddi, F.; Meekins, D.; Michaels, R.; Mihovilovic, M.; Muangma, N.; Muñoz Camacho, C.; Nadel-Turonski, P.; Nuruzzaman, N.; Paremuzyan, R.; Puckett, A.; Punjabi, V.; Qiang, Y.; Rakhman, A.; Rashad, M. N. H.; Riordan, S.; Roche, J.; Russo, G.; Sabatié, F.; Saenboonruang, K.; Saha, A.; Sawatzky, B.; Selvy, L.; Shahinyan, A.; Sirca, S.; Solvignon, P.; Sperduto, M. L.; Subedi, R.; Sulkosky, V.; Sutera, C.; Tobias, W. A.; Urciuoli, G. M.; Wang, D.; Wojtsekhowski, B.; Yao, H.; Ye, Z.; Zana, L.; Zhan, X.; Zhang, J.; Zhao, B.; Zhao, Z.; Zheng, X.; Zhu, P.; Jefferson Lab Hall A Collaboration

    2016-12-01

    We present deeply virtual π0 electroproduction cross-section measurements at xB=0.36 and three different Q2 values ranging from 1.5 to 2 GeV 2 , obtained from Jefferson Lab Hall A experiment E07-007. The Rosenbluth technique is used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component and, thus, is far from the asymptotic limit predicted by perturbative quantum chromodynamics. Nonetheless, an indication of a nonzero longitudinal contribution is provided by the measured interference term σL T. Results are compared with several models based on the leading-twist approach of generalized parton distributions (GPDs). In particular, a fair agreement is obtained with models in which the scattering amplitude includes convolution terms of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. This experiment, together with previous extensive unseparated measurements, provides strong support to the exciting idea that transversity GPDs can be accessed via neutral pion electroproduction in the high-Q2 regime.

  11. AdS/QCD holographic wave function for the ρ meson and diffractive ρ meson electroproduction.

    PubMed

    Forshaw, J R; Sandapen, R

    2012-08-24

    We show that anti-de Sitter/quantum chromodynamics generates predictions for the rate of diffractive ρ-meson electroproduction that are in agreement with data collected at the Hadron Electron Ring Accelerator electron-proton collider.

  12. Recoil Polarization for Delta Excitation in Pion Electroproduction

    SciTech Connect

    J. J. Kelly; R. E. Roche; Z. Chai; M. K. Jones; O. Gayou; A. J. Sarty; S. Frullani; K. Aniol; E. J. Beise; F. Benmokhtar; W. Bertozzi; W. U. Boeglin; T. Botto; E. J. Brash; H. Breuer; E. Brown; E. Burtin; J. R. Calarco; C. Cavata; C. C. Chang; N. S. Chant; J.-P. Chen; M. Coman; D. Crovelli; R. De Leo; S. Dieterich; S. Escoffier; K. G. Fissum; V. Garde; F. Garibaldi; S. Georgakopoulus; S. Gilad; R. Gilman; C. Glashausser; J.-O. Hansen; D. W. Higinbotham; A. Hotta; G. M. Huber; H. Ibrahim; M. Iodice; C. W. de Jager; X. Jiang; A. Klimenko; A. Kozlov; G. Kumbartzki; M. Kuss; L. Lagamba; G. Laveissiere; J. J. LeRose; R. A. Lindgren; N. Liyanage; G. J. Lolos; R. W. Lourie; D. J. Margaziotis; F. Marie; P. Markowitz; S. McAleer; D. Meekins; R. Michaels; B. D. Milbrath; J. Mitchell; J. Nappa; D. Neyret; C. F. Perdrisat; M. Potokar; V. A. Punjabi; T. Pussieux; R. D. Ransome; P. G. Roos; M. Rvachev; A. Saha; S. Sirca; R. Suleiman; S. Strauch; J. A. Templon; L. Todor; P. E. Ulmer; G. M. Urciuoli; L. B. Weinstein; K. Wijesooriya; B. Wojtsekhowski; X. Zheng; and L. Zhu

    2005-08-01

    We measured angular distributions of recoil-polarization response functions for neutral pion electroproduction for W=1.23 GeV at Q{sup 2}=1.0 (GeV/c){sup 2}, obtaining 14 separated response functions plus 2 Rosenbluth combinations; of these, 12 have been observed for the first time. Dynamical models do not describe quantities governed by imaginary parts of interference products well, indicating the need for adjusting magnitudes and phases for nonresonant amplitudes. We performed a nearly model-independent multipole analysis and obtained values for Re(S1+/M1+)=-(6.84+/-0.15)% and Re(E1+/M1+)=-(2.91+/-0.19)% that are distinctly different from those from the traditional Legendre analysis based upon M1+ dominance and sp truncation.

  13. Electroproduction of K+ Λ at JLab Hall-C

    SciTech Connect

    Gogami, T.; Achenbach, P.; Ahmidouch, A.; Albayrak, I.; Androic, D.; Asaturyan, A.; Asaturyan, R.; Ates, O.; Baturin, P.; Badui, R.; Boeglin, W.; Bono, J.; Brash, E.; Carter, P.; Chen, C.; Chiba, A.; Christy, E.; Dalton, M.; Danagoulian, S.; De Leo, R.; Doi, D.; Elaasar, M.; Ent, R.; Fujii, Y.; Furic, M.; Gabrielyan, M.; Gan, L.; Garibaldi, F.; Gaskell, D.; Gasparian, A.; Hashimoto, O.; Horn, T.; Hu, B.; Hungerford, Ed. V.; Jones, M.; Kanda, H.; Kaneta, M.; Kato, S.; Kawai, M.; Kawama, D.; Khanal, H.; Kohl, M.; Liyanage, A.; Luo, W.; Maeda, K.; Margaryan, A.; Markowitz, P.; Maruta, T.; Matsumura, A.; Maxwell, V.; Mkrtchyan, A.; Mkrtchyan, H.; Nagao, S.; Nakamura, S. N.; Narayan, A.; Neville, C.; Niculescu, G.; Niculescu, M. I.; Nunez, A.; Nuruzzaman, .; Okayasu, Y.; Petkovic, T.; Pochodzalla, J.; Qiu, X.; Reinhold, J.; Rodriguez, V. M.; Samanta, C.; Sawatzky, B.; Seva, T.; Shichijo, A.; Tadevosyan, V.; Tang, L.; Taniya, N.; Tsukada, K.; Veilleux, M.; Vulcan, W.; Wesselmann, F. R.; Wood, S. A.; Yamamoto, T.; Ya, L.; Ye, Z.; Yokota, K.; Yuan, L.; Zhamkochyan, S.; Zhu, L.

    2013-02-07

    A Λ hypernuclear spectroscopic experiment, JLab E05-115 was performed at JLab Hall-C in 2009 by the (e, e' K+) reaction. Data of Λ hypernuclei with mass numbers from A = 7 to A = 52 were successfully taken, and the analyses are in progress. A polyethylene (CH2) target was used as a proton target to calibrate energy scales, and to study elementary process of the p(e, e' K+)Λ, Σ0reaction. We report a preliminary differential cross section of K+ Λ electro-production at low Q2 [~0.01 (GeV/c)2] and at small kaon angles (cosΘ$CM\\atop{K}$ ~0.97) in the present article.

  14. Pion Electroproduction form Helium 3, Deuterium, and Hydrogen

    SciTech Connect

    Avery, Stephen Milton

    2002-05-01

    A series of measurements for pion electroproduction from helium-3, deuterium, and hydrogen were completed at the Thomas Jefferson National Accelerator Facility by the NucPi Collaboration. E91003 began taking data in February 1998 and was completed in April 1998. The longitudinal and transverse parts of the differential cross section were extracted, by means of a Rosenbluth type separation, in the direction parallel to the virtual photon, at Q 2 = 0.4 GeV 2 , for W = 1.15 and W = 1.6 GeV. The mass dependence of the longitudinal cross section should provide insight into the surprising apparent absence of any significant cross section enhancement due to excess pions in the nuclear medium.

  15. Color transparency in incoherent electroproduction of {rho} mesons off nuclei

    SciTech Connect

    Nemchik, J.; Kopeliovich, B. Z.; Potashnikova, I. K.

    2013-04-15

    Color transparency (CT) phenomena in elastic electroproduction of vector mesons off nuclei are usually infected by the onset of coherence length (CL) effects. However, at low energies corresponding to the CLAS experiment at Jefferson Lab (JLab), one can study practically the net CT effects, since CL is much shorter than the nuclear radius. We investigate various manifestations of CT effects using rigorous quantum mechanical approach based on the path integral technique. We include also the effects of {rho} meson decay inside the nucleus leading to a rise of the nuclear suppression towards small values of Q{sup 2}. Motivated by the last CLAS data we predict the A, Q{sup 2} and l{sub c} dependence of nuclear transparency for {rho}{sup 0} mesons produced incoherently off nuclei. We also perform predictions for expected signal of CT corresponding to the planned JLab upgrade to 12 GeV electron beam.

  16. Electroproduction of pions on the three-nucleon systems

    SciTech Connect

    Lee, T.S.H.; Chmielewski, C.; Sauer, P.U.

    1995-08-01

    The electroproduction of pions on {sup 3}He is being studied with the assumption that the basic pion production mechanisms can be described by the N(e,e{prime}{pi}) model developed by Nozawa and Lee. In the impulse approximation, the {sup 3}He(e,e{prime}{pi}) cross section is then determined from the N and {Delta} spectral functions generated from Hannover`s three-body calculation including the {Delta}. The objective is to investigate the effects due to the {Delta} components in {sup 3}He, as suggested by Lipkin and Lee. This is being investigated by calculating the ratio between {sup 3}He(e,e{prime}{pi}{sup +}p) and {sup 3}He(e,e{prime}{pi}{sup -}). In a calculation for {sup 3}He(e,e{prime}{pi}{sup +}p) at very high momentum transfer, questions concerning color transparency of {Delta}{sup ++} propagation can be addressed.

  17. Single-spin beam asymmetry in semi-exclusive deep-inelastic electroproduction

    SciTech Connect

    Andrei Afanasev; C. E. Carlson

    2003-05-01

    Recent measurements from Jefferson Lab show significant beam single spin asymmetries in deep inelastic scattering. The asymmetry is due to interference of longitudinal and transverse photoabsorption amplitudes which have different phases induced by the final-state interaction between the struck quark and the target spectators. We developed a dynamical model for a single-spin beam asymmetry in deep-inelastic scattering. Our results are consistent with the experimentally observed magnitude of this effect. We conclude that similar mechanisms involving quark orbital angular momentum ('Sivers effect') are responsible for both target and beam single-spin asymmetries.

  18. Cross sections for the exclusive photon electroproduction on the proton and Generalized Parton Distributions

    SciTech Connect

    Jo, Hyon -Suk

    2015-11-17

    Unpolarized and beam-polarized four-fold cross sections $\\frac{d^4 \\sigma}{dQ^2 dx_B dt d\\phi}$ for the $ep\\to e^\\prime p^\\prime \\gamma$ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 ($Q^2,x_B,t$) bins over the widest phase space ever explored in the valence-quark region. Several models of Generalized Parton Distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD $H$, expected to be the dominant contributor to these observables. Thus, through a leading-twist extraction of Compton Form Factors, these results reveal a tomographic image of the nucleon.

  19. Exclusive {rho}{sup 0} meson electroproduction from hydrogen at CLAS

    SciTech Connect

    Cynthia Hadjidakis; Michel Guidal; Michel Garcon; Jean Laget; Elton Smith; Marc Vanderhaeghen

    2004-08-01

    The longitudinal and transverse components of the cross section for the ep {yields} e{prime}pp{sup 0} reaction were measured in Hall B at Jefferson Laboratory using the CLAS detector. The data were taken with a 4.247 GeV electron beam and were analyzed in a range of x{sub B} from 0.2 to 0.6 and of Q{sup 2} from 1.5 to 3.0 GeV{sup 2}. The data are compared to a Regge model based on effective hadronic degrees of freedom and to a calculation based on Generalized Parton Distributions. It is found that the transverse part of the cross section is well described by the former approach while the longitudinal part can be reproduced by the latter.

  20. Cross sections for the exclusive photon electroproduction on the proton and Generalized Parton Distributions

    DOE PAGES

    Jo, Hyon -Suk

    2015-11-17

    Unpolarized and beam-polarized four-fold cross sectionsmore » $$\\frac{d^4 \\sigma}{dQ^2 dx_B dt d\\phi}$$ for the $$ep\\to e^\\prime p^\\prime \\gamma$$ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 ($$Q^2,x_B,t$$) bins over the widest phase space ever explored in the valence-quark region. Several models of Generalized Parton Distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD $H$, expected to be the dominant contributor to these observables. Thus, through a leading-twist extraction of Compton Form Factors, these results reveal a tomographic image of the nucleon.« less

  1. Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions.

    PubMed

    Jo, H S; Girod, F X; Avakian, H; Burkert, V D; Garçon, M; Guidal, M; Kubarovsky, V; Niccolai, S; Stoler, P; Adhikari, K P; Adikaram, D; Amaryan, M J; Anderson, M D; Anefalos Pereira, S; Ball, J; Baltzell, N A; Battaglieri, M; Batourine, V; Bedlinskiy, I; Biselli, A S; Boiarinov, S; Briscoe, W J; Brooks, W K; Carman, D S; Celentano, A; Chandavar, S; Charles, G; Colaneri, L; Cole, P L; Compton, N; Contalbrigo, M; Crede, V; D'Angelo, A; Dashyan, N; De Vita, R; De Sanctis, E; Deur, A; Djalali, C; Dupre, R; Alaoui, A El; Fassi, L El; Elouadrhiri, L; Fedotov, G; Fegan, S; Filippi, A; Fleming, J A; Garillon, B; Gevorgyan, N; Ghandilyan, Y; Gilfoyle, G P; Giovanetti, K L; Goetz, J T; Golovatch, E; Gothe, R W; Griffioen, K A; Guegan, B; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Harrison, N; Hattawy, M; Hicks, K; Hirlinger Saylor, N; Ho, D; Holtrop, M; Hughes, S M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Jenkins, D; Joo, K; Joosten, S; Keller, D; Khachatryan, G; Khandaker, M; Kim, A; Kim, W; Klein, A; Klein, F J; Kuhn, S E; Kuleshov, S V; Lenisa, P; Livingston, K; Lu, H Y; MacGregor, I J D; McKinnon, B; Meziani, Z E; Mirazita, M; Mokeev, V; Montgomery, R A; Moutarde, H; Movsisyan, A; Munevar, E; Munoz Camacho, C; Nadel-Turonski, P; Net, L A; Niculescu, G; Osipenko, M; Ostrovidov, A I; Paolone, M; Park, K; Pasyuk, E; Phillips, J J; Pisano, S; Pogorelko, O; Price, J W; Procureur, S; Prok, Y; Puckett, A J R; Raue, B A; Ripani, M; Rizzo, A; Rosner, G; Rossi, P; Roy, P; Sabatié, F; Salgado, C; Schott, D; Schumacher, R A; Seder, E; Simonyan, A; Skorodumina, Iu; Smith, G D; Sokhan, D; Sparveris, N; Stepanyan, S; Strakovsky, I I; Strauch, S; Sytnik, V; Tian, Ye; Tkachenko, S; Ungaro, M; Voskanyan, H; Voutier, E; Walford, N K; Watts, D P; Wei, X; Weinstein, L B; Wood, M H; Zachariou, N; Zana, L; Zhang, J; Zhao, Z W; Zonta, I

    2015-11-20

    Unpolarized and beam-polarized fourfold cross sections (d^{4}σ/dQ^{2}dx_{B}dtdϕ) for the ep→e^{'}p^{'}γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q^{2},x_{B},t) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H, expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction x_{B}.

  2. Cross Sections for the Exclusive Photon Electroproduction on the Proton and Generalized Parton Distributions

    NASA Astrophysics Data System (ADS)

    Jo, H. S.; Girod, F. X.; Avakian, H.; Burkert, V. D.; Garçon, M.; Guidal, M.; Kubarovsky, V.; Niccolai, S.; Stoler, P.; Adhikari, K. P.; Adikaram, D.; Amaryan, M. J.; Anderson, M. D.; Anefalos Pereira, S.; Ball, J.; Baltzell, N. A.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Compton, N.; Contalbrigo, M.; Crede, V.; D'Angelo, A.; Dashyan, N.; De Vita, R.; De Sanctis, E.; Deur, A.; Djalali, C.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Fedotov, G.; Fegan, S.; Filippi, A.; Fleming, J. A.; Garillon, B.; Gevorgyan, N.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guler, N.; Guo, L.; Hafidi, K.; Hakobyan, H.; Harrison, N.; Hattawy, M.; Hicks, K.; Hirlinger Saylor, N.; Ho, D.; Holtrop, M.; Hughes, S. M.; Ilieva, Y.; Ireland, D. G.; Ishkhanov, B. S.; Jenkins, D.; Joo, K.; Joosten, S.; Keller, D.; Khachatryan, G.; Khandaker, M.; Kim, A.; Kim, W.; Klein, A.; Klein, F. J.; Kuhn, S. E.; Kuleshov, S. V.; Lenisa, P.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; McKinnon, B.; Meziani, Z. E.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moutarde, H.; Movsisyan, A.; Munevar, E.; Munoz Camacho, C.; Nadel-Turonski, P.; Net, L. A.; Niculescu, G.; Osipenko, M.; Ostrovidov, A. I.; Paolone, M.; Park, K.; Pasyuk, E.; Phillips, J. J.; Pisano, S.; Pogorelko, O.; Price, J. W.; Procureur, S.; Prok, Y.; Puckett, A. J. R.; Raue, B. A.; Ripani, M.; Rizzo, A.; Rosner, G.; Rossi, P.; Roy, P.; Sabatié, F.; Salgado, C.; Schott, D.; Schumacher, R. A.; Seder, E.; Simonyan, A.; Skorodumina, Iu.; Smith, G. D.; Sokhan, D.; Sparveris, N.; Stepanyan, S.; Strakovsky, I. I.; Strauch, S.; Sytnik, V.; Tian, Ye; Tkachenko, S.; Ungaro, M.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zana, L.; Zhang, J.; Zhao, Z. W.; Zonta, I.; CLAS Collaboration

    2015-11-01

    Unpolarized and beam-polarized fourfold cross sections (d4σ /d Q2d xBd t d ϕ ) for the e p →e'p'γ reaction were measured using the CLAS detector and the 5.75-GeV polarized electron beam of the Jefferson Lab accelerator, for 110 (Q2,xB,t ) bins over the widest phase space ever explored in the valence-quark region. Several models of generalized parton distributions (GPDs) describe the data well at most of our kinematics. This increases our confidence that we understand the GPD H , expected to be the dominant contributor to these observables. Through a leading-twist extraction of Compton form factors, these results support the model predictions of a larger nucleon size at lower quark-momentum fraction xB.

  3. Strangeness suppression of qq¯ creation observed in exclusive reactions

    DOE PAGES

    Mestayer, M. D.; Park, K.; Adhikari, K. P.; ...

    2014-10-10

    In this study, we measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK+, pπ0, and nπ+, 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.

  4. Exclusive processes: Tests of coherent QCD phenomena and nucleon substructure at CEBAF

    SciTech Connect

    Brodsky, S.J.

    1994-07-01

    Measurements of exclusive processes such as electroproduction, photoproduction, and Compton scattering are among the most sensitive probes of proton structure and coherent phenomena in quantum chromodynamics. The continuous electron beam at CEBAF, upgraded in laboratory energy to 10--12 GeV, will allow a systematic study of exclusive, semi-inclusive, and inclusive reactions in a kinematic range well-tuned to the study of fundamental nucleon and nuclear substructure. I also discuss the potential at CEBAF for studying novel QCD phenomena at the charm production threshold, including the possible production of nuclear-bound quarkonium.

  5. Induced polarization of Λ(1116) in kaon electroproduction with CLAS

    NASA Astrophysics Data System (ADS)

    Gabrielyan, Marianna; Raue, Brian; Carman, Daniel S.; Park, Kijun

    2013-10-01

    The CLAS Collaboration is using the p(e,e'K+p)π- reaction to perform a measurement of the induced polarization of the electroproduced Λ(1116). The parity-violating weak decay of the Λ into p&pgr- (64%) allows extraction of the recoil polarization of the Λ. This study uses the CEBAF Large Acceptance Spectrometer (CLAS) to detect the scattered electron, the kaon, and the decay proton. CLAS allows for a large kinematic acceptance with 0.8 ≤ Q2 ≤ 3.5 GeV2, 1.6 ≤ W ≤ 3.0 GeV, as well as the kaon scattering angle. In this experiment a 5.5 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. The goal is to map out the kinematic dependencies for this polarization observable to provide new constraints for theoretical models of the electromagnetic production of kaon-hyperon final states. Along with previously published photo- and electro-production cross sections and polarization observables from CLAS, SAPHIR, and GRAAL, these data are needed in a coupled-channel analysis to identify previously unobserved s-channel resonances.

  6. Spectroscopy of LiΛ9 by electroproduction

    DOE PAGES

    Urciuoli, G. M.; Cusanno, F.; Marrone, S.; ...

    2015-03-01

    Background: In the absence of accurate data on the free two-body hyperon-nucleon interaction, the spectra of hypernuclei can provide information on the details of the effective hyperon-nucleon interaction. Purpose: To obtain a high-resolution spectrum for the 9Be(e,e'K+)9ΛLi reaction. Method: Electroproduction of the hypernucleus 9ΛLi has been studied for the first time with sub-MeV energy resolution in Hall A at Jefferson Lab on a 9Be target. In order to increase the counting rate and to provide unambiguous kaon identification, two superconducting septum magnets and a Ring Imaging CHerenkov detector (RICH) were added to the Hall A standard equipment. Results: The crossmore » section to low-lying states of 9ΛLi is concentrated within 3 MeV of the ground state and can be fitted with four peaks. The positions of the doublets agree with theory while a disagreement could exist with respect to the relative strengths of the peaks in the doublets. A Λ separation energy, BΛ, of 8.36±0.08 (stat.) ±0.08 (syst.) MeV was measured, in agreement with an earlier experiment.« less

  7. Scaling study of the pion electroproduction cross sections and the pion form factor

    SciTech Connect

    Tanja Horn; Xin Qian; John Arrington; Razmik Asaturyan; Fatiha Benmokthar; Werner Boeglin; Peter Bosted; Antje Bruell; Eric Christy; Eugene Chudakov; Ben Clasie; Mark Dalton; AJI Daniel; Donal Day; Dipangkar Dutta; Lamiaa El Fassi; Rolf Ent; Howard Fenker; J. Ferrer; Nadia Fomin; H. Gao; K Garrow; Dave Gaskell; C Gray; G. Huber; M. Jones; N Kalantarians; C. Keppel; K Kramer; Y Li; Y Liang; A. Lung; S Malace; P. Markowitz; A. Matsumura; D. Meekins; T Mertens; T Miyoshi; H. Mykrtchyan; R. Monson; T. Navasardyan; G. Niculescu; I. Niculescu; Y. Okayasu; A. Opper; C Perdrisat; V. Punjabi; A. Rauf; V. Rodriguez; D. Rohe; J Seely; E Segbefia; G. Smith; M. Sumihama; V. Tadevoyan; L Tang; V. Tvaskis; A. Villano; W. Vulcan; F. Wesselmann; S. Wood; L. Yuan; X. Zheng

    2007-07-12

    The $^{1}$H($e,e^\\prime \\pi^+$)n cross section was measured for a range of four-momentum transfer up to $Q^2$=3.91 GeV$^2$ at values of the invariant mass, $W$, above the resonance region. The $Q^2$-dependence of the longitudinal component is consistent with the $Q^2$-scaling prediction for hard exclusive processes. This suggests that perturbative QCD concepts are applicable at rather low values of $Q^2$. Pion form factor results, while consistent with the $Q^2$-scaling prediction, are inconsistent in magnitude with perturbative QCD calculations. The extraction of Generalized Parton Distributions from hard exclusive processes assumes the dominance of the longitudinal term. However, transverse contributions to the cross section are still significant at $Q^2$=3.91 GeV$^2$.

  8. Electroproduction of neutral pions in the Hall A at the Jefferson Laboratory; Electroproduction de pions neutres dans le Hall A au Jefferson Laboratory

    SciTech Connect

    Fuchey, Eric

    2010-06-01

    The past decade has seen a strong evolution of the study of the hadron structure through exclusive processes, allowing to access to a more complete description of this structure. Exclusive processes include DVCS (Deeply Virtual Compton Scattering) as well as hard exclusive meson production. This document is particularly focussed on the latter, and more particularly on exclusive neutral pion production. In this thesis is described the analysis of triple coincidence events H(e, e'γγ)X, which were a consequent by-product of the DVCS experiment which occured during Fall 2004 at Jefferson Lab Hall A, to extract the ep → epπ0 cross section. This cross section has been measured at two values of four-momentum transfer Q2 = 1.9 GeV2 and Q2 = 2.3 GeV2. The statistical precision for these measurements is achieved at better than 5 %. The kinematic range allows to study the evolution of the extracted cross section as a function of Q2 and W. Results are be confronted with Regge inspired calculations and Generalized (GPD) predictions. An intepretation of our

  9. Quasifree Lambda, Sigma^0, and Sigma^- electroproduction from 1,2H, 3,4He, and Carbon

    SciTech Connect

    F. Dohrmann; A. Ahmidouch; C.S. Armstrong; J. Arrington; R. Asaturyan; S. Avery; K. Bailey; H. Bitao; H. Breuer; D.S. Brown; R. Carlini; J. Cha; N. Chant; E. Christy; A. Cochran; L. Cole; J. Crowder; S. Danagoulian; M. Elaasar; R. Ent; H. Fenker; Y. Fujii; L. Gan; K. Garrow; D.F. Geesaman; P. Gueye; K. Hafidi; W. Hinton; H. Juengst; C. Keppel; Y. Liang; J.H. Liu; A. Lung; D. Mack; P. Markowitz; J. Mitchell; T. Miyoshi; H. Mkrtchyan; S.K. Mtingwa; B. Mueller; G. Niculescu; I. Niculescu; D. Potterveld; B.A. Raue; P.E. Reimer; J. Reinhold; J. Roche; M. Sarsour; Y. Sato; R.E. Segel; A. Semenov; S. Stepanyan; V. Tadevosyan; S. Tajima; L. Tang; A. Uzzle; S. Wood; H. Yamaguchi; C. Yan; L. Yuan; B. Zeidman; M. Zeier; B. Zihlmann

    2007-07-30

    Kaon electroproduction from light nuclei and hydrogen, using 1H, 2H, 3He, 4He, and Carbon targets has been measured at Jefferson Laboratory. The quasifree angular distributions of Lambda and Sigma hyperons were determined at Q^2= 0.35(GeV/c)^2 and W= 1.91GeV. Electroproduction on hydrogen was measured at the same kinematics for reference.

  10. Semi-inclusive charged-pion electroproduction off protons and deuterons: Cross sections, ratios, and access to the quark-parton model at low energies

    DOE PAGES

    Asaturyan, R.; Ent, R.; Mkrtchyan, H.; ...

    2012-01-01

    A large set of cross sections for semi-inclusive electroproduction of charged pions (π±) from both proton and deuteron targets was measured. The data are in the deep-inelastic scattering region with invariant mass squared W2 > 4 GeV2 and range in four-momentum transfer squared 2 < Q2 < 4 (GeV/c)2, and cover a range in the Bjorken scaling variable 0.2 < x < 0.6. The fractional energy of the pions spans a range 0.3 < z < 1, with small transverse momenta with respect to the virtual-photon direction, Pt2 < 0.2 (GeV/c)2. The invariant mass that goes undetected, Mx or W',more » is in the nucleon resonance region, W' < 2 GeV. The new data conclusively show the onset of quark-hadron duality in this process, and the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark → pion production mechanisms. The x, z and Pt2 dependences of several ratios (the ratios of favored-unfavored fragmentation functions, charged pion ratios, deuteron-hydrogen and aluminum-deuteron ratios for π+ and π-) have been studied. The ratios are found to be in good agreement with expectations based upon a high-energy quark-parton model description. We find the azimuthal dependences to be small, as compared to exclusive pion electroproduction, and consistent with theoretical expectations based on tree-level factorization in terms of transverse-momentum-dependent parton distribution and fragmentation functions. In the context of a simple model, the initial transverse momenta of d quarks are found to be slightly smaller than for u quarks, while the transverse momentum width of the favored fragmentation function is about the same as for the unfavored one, and both fragmentation widths are larger than the quark widths.« less

  11. Deeply virtual and exclusive production of the omega meson

    SciTech Connect

    M. Garcon; L. Morand; D. Dore; J.-M. Laget; S. Morrow; F. Sabatie

    2005-04-01

    Exclusive {omega} electroproduction off the proton was measured at the highest possible four-momentum transfer with the (close to) 6 GeV beam now available at CEBAF. Cross sections are presented, together with an analysis of the {omega} spin density matrix elements. Indications are that {pi}{sup 0} exchange in the t-channel (or rather the exchange of the corresponding saturating Regge trajectory) seems to dominate the process {gamma}*p {yields} {omega}p, even for photon virtuality Q{sup 2} as large as 5 GeV{sup 2}. Contributions of the handbag type, related to Generalized Parton Distributions in the nucleon, are therefore difficult to extract from this particular process.

  12. Observation of Scaling in the Ratio of Electroproduction Yields of Three Meson-Baryon Final States: K+ Λ , nπ+ , pπ0

    NASA Astrophysics Data System (ADS)

    Mestayer, Mac; Park, Kijun; CLAS Collaboration

    2013-10-01

    We measured the ratios of electroproduction cross-sections for three exclusive meson-baryon final states: K+ Λ , pπ0 , and nπ+ . After averaging over the angle between leptonic and hadronic production planes we observe only a moderate kinematic dependence (``scaling'') of the ratios with respect to Q2, W and cosθ* . Our results agree well with a simple calculation based on the ``Lund model'' for hadronization in which the color flux-tube is broken by the creation of q q pairs and which works well up to center-of-mass energies equal to the Z0 mass. Interestingly, our measured global average K+ Λ / nπ+ production ratio of 0 . 278 +/- 0 . 013 +/- 0 . 042 agrees with the nominal value of the ``strangeness suppression factor'' of the Lund model of 0 . 3 ; extending the universality of this concept to the exclusive limit in which only a single qq pair is created and for which an explict two-body phase-space correction can be performed. In addition, our measurement of the pπ0 / nπ+ ratio of 0 . 467 +/- 0 . 008 +/- 0 . 086 is consistent with equality of the uū and dd pair creation probabilities.

  13. Nucleon resonance electroproduction at high momentum transers: Results from SLAC and suggestions for CEBAF

    SciTech Connect

    Keppel, C.

    1994-04-01

    Nucleon resonance electroproduction results from SLAC Experiment E14OX are presented. A CEBAF facility with doubled energy would enable similar high momentum transfer measurements to be made with greater accuracy. Of particular interest are the Delta P{sub 33}(1232) resonance form factor and R = {sigma}{sub L}/{sigma}{sub T}, the ratio of the longitudinal and transverse components of the cross section. A suggestion is made to study these quantities in conjunction with Bloom-Gilman duality.

  14. Electroproduction of strangeness on (Lambda)H-3,4 bound states on helium

    SciTech Connect

    F. Dohrmann; D. Abbott; A. Ahmidouch; P. Ambrozewicz; C. S. Armstrong; J. Arrington; R. Asaturyan; K. Assamagan; S. Avery; K. Bailey; S. Beedoe; H. Bitao; H. Breuer; D. S. Brown; R. Carlini; J. Cha; N. Chant; E. Christy; A. Cochran; L. Cole; G. Collins; C. Cothran; J. Crowder; W. J. Cummings; S. Danagoulian; F. Duncan; J. Dunne; D. Dutta; T. Eden; M. Elaasar; R. Ent; L. Ewell; H. Fenker; H. T. Fortune; Y. Fujii; L. Gan; H. Gao; K. Garrow; D. F. Geesaman; P. Gueye; K. Gustafsson; K. Hafidi; J. O. Hansen; W. Hinton; H. E. Jackson; H. Juengst; C. Keppel; A. Klein; D. Koltenuk; Y. Liang; J. H. Liu; A. Lung; D. Mack; R. Madey; P. Markowitz; C. J. Martoff; D. Meekins; J. Mitchell; T. Miyoshi; H. Mkrtchyan; R. Mohring; S. K. Mtingwa; B. Mueller; T. G. O'Neill; G. Niculescu; I. Niculescu; D. Potterveld; J. W. Price; B. A. Raue; P. E. Reimer; J. Reinhold; J. Roche; P. Roos; M. Sarsour; Y. Sato; G. Savage; R. Sawafta; R. E. Segel; A. Yu. Semenov; S. Stepanyan; V. Tadevosian; S. Tajima; L. Tang; B. Terburg; A. Uzzle; S. Wood; H. Yamaguchi; C. Yan; C. Yan; L. Yuan; M. Zeier; B. Zeidman; B. Zihlmann

    2005-05-01

    The A(e,eK+)X reaction has been investigated at Jefferson Laboratory. Data were taken for Q{sup 2} approx. 0.35 GeV{sup 2} at a beam energy of 3.245 GeV for 1H,3He and 4He targets. Evidence for Lambda-hypernuclear bound states is seen for 3,4He targets. This is the first time that the electroproduction of these hypernuclei has been observed.

  15. Probing Nucleon Structure with Meson Electro-production in Hall C

    SciTech Connect

    Wood, Stephen

    2011-02-01

    Meson electro-production is used in Hall C at Jefferson Lab to probe nucleon, baryon and nuclear structure. The experimental program in Hall C includes studies of semi-inclusive pion production, p, d(e, e'π±)X, where low energy factorization has been observed, suggesting that these reactions can be used to probe nucleon structure, including transverse momentum distributions of quarks, at energies available at JLab after the upcoming 12 GeV upgrade.

  16. Dynamical coupled-channels model of meson photo- and electroproduction in the nucleon resonance region

    NASA Astrophysics Data System (ADS)

    Sato, T.

    2007-12-01

    A dynamical approach of the meson production reaction for extracting nucleon resonance parameters has been developed. We report on the γ N Δ form factors extracted from the recent pion electroproduction data and the coupled-channels model of π N scattering up to W ≤ 2 GeV. An analysis of the resonance poles extracted using the speed-plot and time-delay methods is briefly discussed.

  17. Exclusive processes at JLab at 6 GeV

    SciTech Connect

    Kim, Andrey

    2015-01-01

    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 π0 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 π0 exclusive production data within the framework of the GPD-based model provides a unique opportunity to access the chiral-odd GPDs.

  18. Excited baryon structure using exclusive reactions with CLAS12

    NASA Astrophysics Data System (ADS)

    Carman, Daniel S.

    2016-05-01

    Studying excited nucleon structure through exclusive electroproduction reactions is an important avenue for exploring the nature of the non-perturbative strong interaction. Electrocouplings for N* states in the mass range below 1.8 GeV have been determined from analyses of CLAS πN, ηN, and ππN data. This work made it clear that consistency of independent analyses of exclusive channels with different couplings and non-resonant backgrounds but the same N* electro-excitation amplitudes, is essential to have confidence in the extracted results. In terms of hadronic coupling, many high-lying N* states preferentially decay through the ππN channel instead of πN. Data from the KY channels will therefore be critical to provide an independent analysis with which to compare the extracted electrocouplings for the high-lying N* states against those determined from the πN and ππN channels. A program to study excited N* decays to non-strange and strange exclusive final states using CLAS12 will measure differential cross sections to be used as input to extract the γvNN* transition form factors for the most prominent N* states in the range of invariant energy W up 3 GeV in the virtually unexplored domain of momentum transfers Q2 up to 12 GeV2.

  19. A study of longitudinal charged-pion electroproduction in D, {sup 3}He, and {sup 4}He

    SciTech Connect

    Jackson, H.E.; Coulter, K.P.; Geesaman, D.F.

    1995-08-01

    Recent studies of pion electroproduction on the deuteron carried out by the ANL group at ALS, Saclay, show that even in the weakly-bound deuteron, multinucleon processes alter the electroproduction amplitudes in the forward direction. The data provide the first experimental indications for a significant change in the pion-nucleon coupling for nucleons bound in nuclei. It is clear that forward-angle electroproduction may be a sensitive probe of the properties of the pion coupling in the nuclear medium. At CEBAF, we will study longitudinal charged-pion electroproduction (in the excitation region below the delta isobar) along the direction of the momentum transfer where the charge scattering process dominates. Direct comparison of the cross section per nucleon in deuterium and the helium isotopes with the experimental value for the free nucleon will provide estimates of the strength of the nuclear pion field. A Rosenbluth separation of the longitudinal and transverse cross sections will be performed for four-momentum transfers of 2.5 and 10 fm{sup -2}. Measurements for a number of light nuclei will provide useful data on the sensitivity of longitudinal electroproduction to nuclear binding effects. If current conceptions of pion-exchange currents in nuclei are correct, longitudinal electroproduction will be suppressed at the lower momentum transfer and enhanced at the higher momentum transfer by multinucleon processes. If on the other hand, as suggested by recent data from Drell-Yan studies of antiquark structure functions, there is no such enhancement, a reformulation of pion exchange models of the medium- and short-range properties of nuclear forces will be required. Our proposal to carry out such a series of measurements at CEBAF using the coincident-pair spectrometer system planned for Hall C was approved. Pions will be observed in the short-orbit spectrometer (SOS) which will serve as the second arm.

  20. Diffractive electroproduction of s{bar s} mesons off nuclei at CEBAF energies

    SciTech Connect

    Benhar, O.; Nikolaev, N.N.; Zakharov, B.G.

    1994-04-01

    The authors discuss diffractive incoherent electroproduction of s{bar s} mesons off nuclear targets at beam energies that are expected to be available at CEBAF (5-8 GeV). The Q{sup 2} and target mass dependence of the {phi} and {phi}{prime} transparency ratios has been studied within a theoretical approach in which the propagation of the s{bar s} pair through the nuclear medium is described in terms of the quantum mechanical evolution operator. The authors predict a complex pattern of nuclear effects, whose experimental study may provide information on several issues relevant to the understanding of QCD, both in the perturbative and nonperturbative regimes.

  1. Measurement of Beam-Spin Asymmetries for Deep Inelastic pi{sup +} Electroproduction

    SciTech Connect

    H. Avakian; Volker D. Burkert; Latifa Elouadrhiri; et. al.

    2002-12-01

    We report the first evidence for a non-zero beam-spin azimuthal asymmetry in the electroproduction of positive pions in the deep-inelastic region. Data have been obtained using a polarized electron beam of 4.3 GeV and with the CLAS detector at the Thomas Jefferson National Accelerator Facility (JLab). The amplitude of the sin phi modulation increases with the momentum of the pion relative to the virtual photon, z, with an average amplitude of 0.038+/-0.005+/-0.003 for 0.5

  2. Observation of coherent pi0 electroproduction on deuterons at large momentum transfer

    SciTech Connect

    Tomasi, Egle; Bimbot, Louis; Danagoulian, Samuel; Gustafsson, Kenneth; Mack, David; Mkrtchyan, Hamlet; Rekalo, M.P.

    2003-03-01

    The first experimental results for coherent $\\pi^0$-electroproduction on the deuteron, $e+d\\to e+d +\\pi^0$, at large momentum transfer, are reported. The experiment was performed at Jefferson Laboratory at an incident electron energy of 4.05 GeV. A large pion production yield has been observed in a kinematical region for 1.1$

  3. High Resolution Spectroscopy of {sub {lambda}}{sup 12}B by Electroproduction

    SciTech Connect

    Iodice, M.; Cusanno, F.; Urciuoli, G. M.; Acha, A.; Ambrozewicz, P.; Coman, L.; Markowitz, P.; Moteabbed, M.; Raue, B.; Reinhold, J.; Aniol, K. A.; Margaziotis, D. J.; Baturin, P.; Jiang, X.; McCormick, K.; Bertin, P. Y.; Camsonne, A.; Ferdi, C.; Blomqvist, K. I.

    2007-08-03

    An experiment measuring electroproduction of hypernuclei has been performed in hall A at Jefferson Lab on a {sup 12}C target. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a ring imaging Cherenkov detector were added to the hall A standard equipment. An unprecedented energy resolution of less than 700 keV FWHM has been achieved. Thus, the observed {sub {lambda}}{sup 12}B spectrum shows for the first time identifiable strength in the core-excited region between the ground-state s-wave {lambda} peak and the 11 MeV p-wave {lambda} peak.

  4. Semi-inclusive charged-pion electroproduction off protons and deuterons: Cross sections, ratios, and access to the quark-parton model at low energies

    SciTech Connect

    Asaturyan, R.; Ent, R.; Mkrtchyan, H.; Navasardyan, T.; Tadevosyan, V.; Adams, G. S.; Ahmidouch, A.; Angelescu, T.; Arrington, J.; Asaturyan, A.; Baker, O. K.; Benmouna, N.; Bertoncini, C.; Blok, H. P.; Boeglin, W. U.; Bosted, P. E.; Breuer, H.; Christy, M. E.; Connell, S. H.; Cui, Y.; Dalton, M. M.; Danagoulian, S.; Day, D.; Dunne, J. A.; Dutta, D.; El Khayari, N.; Fenker, H. C.; Frolov, V. V.; Gan, L.; Gaskell, D.; Hafidi, K.; Hinton, W.; Holt, R. J.; Horn, T.; Huber, G. M.; Hungerford, E.; Jiang, X.; Jones, M.; Joo, K.; Kalantarians, N.; Kelly, J. J.; Keppel, C. E.; Kubarovsky, V.; Li, Y.; Liang, Y.; Mack, D.; Malace, S. P.; Markowitz, P.; McGrath, E.; McKee, P.; Meekins, D. G.; Mkrtchyan, A.; Moziak, B.; Niculescu, G.; Niculescu, I.; Opper, A. K.; Ostapenko, T.; Reimer, P. E.; Reinhold, J.; Roche, J.; Rock, S. E.; Schulte, E.; Segbefia, E.; Smith, C.; Smith, G. R.; Stoler, P.; Tang, L.; Ungaro, M.; Uzzle, A.; Vidakovic, S.; Villano, A.; Vulcan, W. F.; Wang, M.; Warren, G.; Wesselmann, F. R.; Wojtsekhowski, B.; Wood, S. A.; Xu, C.; Yuan, L.; Zheng, X.

    2012-01-01

    A large set of cross sections for semi-inclusive electroproduction of charged pions (π±) from both proton and deuteron targets was measured. The data are in the deep-inelastic scattering region with invariant mass squared W2 > 4 GeV2 and range in four-momentum transfer squared 2 < Q2 < 4 (GeV/c)2, and cover a range in the Bjorken scaling variable 0.2 < x < 0.6. The fractional energy of the pions spans a range 0.3 < z < 1, with small transverse momenta with respect to the virtual-photon direction, Pt2 < 0.2 (GeV/c)2. The invariant mass that goes undetected, Mx or W', is in the nucleon resonance region, W' < 2 GeV. The new data conclusively show the onset of quark-hadron duality in this process, and the relation of this phenomenon to the high-energy factorization ansatz of electron-quark scattering and subsequent quark → pion production mechanisms. The x, z and Pt2 dependences of several ratios (the ratios of favored-unfavored fragmentation functions, charged pion ratios, deuteron-hydrogen and aluminum-deuteron ratios for π+ and π-) have been studied. The ratios are found to be in good agreement with expectations based upon a high-energy quark-parton model description. We find the azimuthal dependences to be small, as compared to exclusive pion electroproduction, and consistent with theoretical expectations based on tree-level factorization in terms of transverse-momentum-dependent parton distribution and fragmentation functions. In the context of a simple model, the initial transverse momenta of d quarks are found to be slightly smaller than for u quarks, while the transverse momentum width of the favored fragmentation function is about the same as for the unfavored one, and both fragmentation widths are larger than the quark widths.

  5. High Resolution Spectroscopy of 16N_Lambda by Electroproduction

    SciTech Connect

    Cusanno, Francesco; Urciuoli, Guido; Acha Quimper, Armando; Ambrozewicz, Pawel; Aniol, Konrad; Baturin, Pavlo; Bertin, Pierre; Benaoum, Hachemi; Blomqvist, Ingvar; Boeglin, Werner; Breuer, Herbert; Brindza, Paul; Bydzovsky, Petr; Camsonne, Alexandre; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chen, Jian-Ping; Choi, Seonho; Chudakov, Eugene; Cisbani, Evaristo; Colilli, Stefano; Coman, Luminita; Craver, Brandon; de Cataldo, Giacinto; De Jager, Cornelis; De Leo, Raffaele; Deur, Alexandre; Ferdi, Catherine; Feuerbach, Robert; Folts, Edward; Frullani, Salvatore; Garibaldi, Franco; Gayou, Olivier; Giuliani, Fausto; Gomez, Javier; Gricia, Massimo; Hansen, Jens-Ole; Hayes, David; Higinbotham, Douglas; Holmstrom, Timothy; Hyde, Charles; Ibrahim, Hassan; Iodice, Mauro; Jiang, Xiaodong; Kaufman, Lisa; Kino, Kouichi; Kross, Brian; Lagamba, Luigi; LeRose, John; Lindgren, Richard; Lucentini, Maurizio; Margaziotis, Demetrius; Markowitz, Pete; Marrone, Stefano; Meziani, Zein-Eddine; McCormick, Kathy; Michaels, Robert; Millener, D.; Miyoshi, Toshinobu; Moffit, Bryan; Monaghan, Peter; Moteabbed, Maryam; Munoz Camacho, Carlos; Nanda, Sirish; Nappi, E.; Nelyubin, Vladimir; Norum, Blaine; Okasyasu, Y.; Paschke, Kent; Perdrisat, Charles; Piasetzky, Eliazer; Punjabi, Vina; Qiang, Yi; Raue, Brian; Reimer, Paul; Reinhold, Joerg; Reitz, Bodo; Roche, Rikki; Rodriguez, Victor; Saha, Arunava; Santavenere, Fabio; Sarty, Adam; Segal, John; Shahinyan, Albert; Singh, Jaideep; Sirca, Simon; Snyder, Ryan; Solvignon, Patricia; Sotona, M.; Sotona, Miloslav; Sotona, M.; Sotona, Miloslav; Sotona, M.; Sotona, Miloslav; Sotona, M.; Sotona, Miloslav; Subedi, Ramesh; Sulkosky, Vince; Sulkosky, Vincent; Sulkosky, Vince; Sulkosky, Vincent; Suzuki, Tomokazu; Ueno, Hiroaki; Ulmer, Paul; Veneroni, P.P.; Voutier, Eric; Wojtsekhowski, Bogdan; Zeng, X.; Zorn, Carl

    2009-01-01

    An experimental study of the 16O(e, e'K+)16N_Lambda reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e, e'K+)Lambda,Sigma_0 exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76 ± 0.16 MeV was obtained for 16N_Lambda with better precision than previous measurements on the mirror hypernucleus 16O_Lambda. Precise energies have been determined for peaks arising from a Lambda in s and p orbits coupled to the p1/2 and p3/2 hole states of the 15N core nucleus.

  6. Precision Measurements of Neutral Pion Electroproduction Near Threshold: A Test of Chiral QCD Dynamics

    SciTech Connect

    Lindgren, Richard A.; Chirapatpimol, Khem; Smith, Lee Cole

    2013-08-01

    Preliminary results are presented from an experiment to measure {pi}{sup 0} electroproduction at and above threshold using the p(e;e' p){pi}{sup 0} reaction. The data were taken at a beam energy of 1192 MeV using a two-spectrometer setup in Hall A at Jefferson Lab. For the first time in {pi}{sup 0} threshold electroproduction, complete coverage of the {phi}{sub {pi}}* and {theta}{sub {pi}}* angles in the center-of-mass (C.M.) was obtained for the invariant mass region up to {Delta}W=18 MeV above the {pi}{sup 0} threshold. At the same time our invariant momentum transfer squared covers the range Q{sup 2} = 0.05-0.15 (GeV/c){sup 2} with twelve bins in Q{sup 2}. The improved kinematic coverage in C.M., W and Q{sup 2} will better constrain theoretical interpretations of the data using phenomenological models and QCD-inspired models such as Heavy Baryon Chiral Perturbation Theory.

  7. 37 CFR 404.7 - Exclusive, co-exclusive and partially exclusive licenses.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Exclusive, co-exclusive and... Exclusive, co-exclusive and partially exclusive licenses. (a)(1) Exclusive, co-exclusive or partially... practical application or otherwise promote the invention's utilization by the public. (B) Exclusive,...

  8. 37 CFR 404.7 - Exclusive, co-exclusive and partially exclusive licenses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Exclusive, co-exclusive and..., co-exclusive and partially exclusive licenses. (a)(1) Exclusive, co-exclusive or partially exclusive... practical application or otherwise promote the invention's utilization by the public. (B) Exclusive,...

  9. 37 CFR 404.7 - Exclusive, co-exclusive and partially exclusive licenses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Exclusive, co-exclusive and... Exclusive, co-exclusive and partially exclusive licenses. (a)(1) Exclusive, co-exclusive or partially... practical application or otherwise promote the invention's utilization by the public. (B) Exclusive,...

  10. 37 CFR 404.7 - Exclusive, co-exclusive and partially exclusive licenses.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Exclusive, co-exclusive and... Exclusive, co-exclusive and partially exclusive licenses. (a)(1) Exclusive, co-exclusive or partially... practical application or otherwise promote the invention's utilization by the public. (B) Exclusive,...

  11. 37 CFR 404.7 - Exclusive, co-exclusive and partially exclusive licenses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Exclusive, co-exclusive and..., co-exclusive and partially exclusive licenses. (a)(1) Exclusive, co-exclusive or partially exclusive... practical application or otherwise promote the invention's utilization by the public. (B) Exclusive,...

  12. Strangeness suppression of qq¯ creation observed in exclusive reactions

    SciTech Connect

    Mestayer, M. D.; Park, K.; Adhikari, K. P.; Aghasyan, M.; Pereira, S. Anefalos; Ball, J.; Battaglieri, M.; Batourine, V.; Bedlinskiy, I.; Biselli, A. S.; Boiarinov, S.; Briscoe, W. J.; Brooks, W. K.; Burkert, V. D.; Carman, D. S.; Celentano, A.; Chandavar, S.; Charles, G.; Colaneri, L.; Cole, P. L.; Contalbrigo, M.; Cortes, O.; Crede, V.; D’Angelo, A.; Dashyan, N.; De Vita, R.; Deur, A.; Djalali, C.; Doughty, D.; Dupre, R.; Alaoui, A. El; Fassi, L. El; Elouadrhiri, L.; Eugenio, P.; Fedotov, G.; Fleming, J. A.; Forest, T. A.; Garillon, B.; Garçon, M.; Ghandilyan, Y.; Gilfoyle, G. P.; Giovanetti, K. L.; Girod, F. X.; Goetz, J. T.; Golovatch, E.; Gothe, R. W.; Griffioen, K. A.; Guegan, B.; Guidal, M.; Hakobyan, H.; Hanretty, C.; Hattawy, M.; Holtrop, M.; Hughes, S. M.; Hyde, C. E.; Ilieva, Y.; Ireland, D. G.; Jiang, H.; Jo, H. S.; Joo, K.; Keller, D.; Khandaker, M.; Kim, A.; Kim, W.; Koirala, S.; Kubarovsky, V.; Kuleshov, S. V.; Lenisa, P.; Levine, W. I.; Livingston, K.; Lu, H. Y.; MacGregor, I. J. D.; Mayer, M.; McKinnon, B.; Meyer, C. A.; Mirazita, M.; Mokeev, V.; Montgomery, R. A.; Moody, C. I.; Moutarde, H.; Movsisyan, A.; Camacho, C. Munoz; Nadel-Turonski, P.; Niccolai, S.; Niculescu, G.; Niculescu, I.; Osipenko, M.; Ostrovidov, A. I.; Pappalardo, L. L.; Paremuzyan, R.; Peng, P.; Phelps, W.; Pisano, S.; Pogorelko, O.; Pozdniakov, S.; Price, J. W.; Protopopescu, D.; Puckett, A. J. R.; Raue, B. A.; Rimal, D.; Ripani, M.; Rizzo, A.; Rosner, G.; Roy, P.; Sabatié, F.; Saini, M. S.; Schott, D.; Schumacher, R. A.; Simonyan, A.; Sokhan, D.; Strauch, S.; Sytnik, V.; Tang, W.; Tian, Ye; Ungaro, M.; Vernarsky, B.; Vlassov, A. V.; Voskanyan, H.; Voutier, E.; Walford, N. K.; Watts, D. P.; Wei, X.; Weinstein, L. B.; Wood, M. H.; Zachariou, N.; Zhang, J.; Zhao, Z. W.; Zonta, I.

    2014-10-10

    In this study, we measured the ratios of electroproduction cross sections from a proton target for three exclusive meson-baryon final states: ΛK+, pπ0, and nπ+, 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.

  13. Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry

    NASA Astrophysics Data System (ADS)

    McKenney, J. R.; Sato, Nobuo; Melnitchouk, W.; Ji, Chueng-Ryong

    2016-03-01

    We examine the efficacy of pion exchange models to simultaneously describe leading neutron electroproduction at HERA and the d ¯ -u ¯ flavor asymmetry in the proton. A detailed χ2 analysis of the ZEUS and H1 cross sections, when combined with constraints on the pion flux from Drell-Yan data, allows regions of applicability of one-pion exchange to be delineated. The analysis disfavors several models of the pion flux used in the literature and yields an improved extraction of the pion structure function and its uncertainties at parton momentum fractions in the pion of 4 ×10-4≲xπ≲0.05 at a scale of Q2=10 GeV2 . Based on the fit results, we provide estimates for leading proton structure functions in upcoming tagged deep-inelastic scattering experiments at Jefferson Lab on the deuteron with forward protons.

  14. Vector meson J/Ψ,phi electro-production in QCD

    NASA Astrophysics Data System (ADS)

    Lu, Juan; Zhou, Li-Juan

    2010-04-01

    We study the vector meson electro-production off the proton in a QCD inspired model. A calculation of the differential cross section is performed for the J/Ψ,phi meson off the proton. The theoretical results are consistent with the experimental data, and remind us to consider the contribution from the tensor glueball and Odderon to the differential cross section. Since gluons interact among themselves via self-interaction, the gluons can form a glueball with quantum numbers IG, JPC = 0+, 2++, with a decay width Γt = 100 MeV and mass of mG = 2.23 GeV. The three gluons can form a three gluon color bound state with charge conjugation quantum number C = -1. This study is quite important to verify the validity of QCD and to search for new particles (tensor glueball and Odderon) as well as quest for new physics.

  15. Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry

    SciTech Connect

    McKenney, Joshua R.; Sato, Nobuo; Melnitchouk, Wally; Ji, Chueng-Ryong

    2016-03-07

    In this paper, we examine the efficacy of pion exchange models to simultaneously describe leading neutron electroproduction at HERA and the $\\bar{d}-\\bar{u}$ flavor asymmetry in the proton. A detailed $\\chi^2$ analysis of the ZEUS and H1 cross sections, when combined with constraints on the pion flux from Drell-Yan data, allows regions of applicability of one-pion exchange to be delineated. The analysis disfavors several models of the pion flux used in the literature, and yields an improved extraction of the pion structure function and its uncertainties at parton momentum fractions in the pion of $4 \\times 10^{-4} \\lesssim x_\\pi \\lesssim 0.05$ at a scale of $Q^2$=10 GeV$^2$. Also, we provide estimates for leading proton structure functions in upcoming tagged deep-inelastic scattering experiments on the deuteron with forward protons, based on the fit results, at Jefferson Lab.

  16. Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry

    SciTech Connect

    McKenney, Joshua R.; Sato Gonzalez, Nobuo; Melnitchouk, Wally; Ji, Chueng-Ryong

    2016-03-01

    We examine the efficacy of pion exchange models to simultaneously describe leading neutron electroproduction at HERA and the $\\bar{d}-\\bar{u}$ flavor asymmetry in the proton. A detailed $\\chi^2$ analysis of the ZEUS and H1 cross sections, when combined with constraints on the pion flux from Drell-Yan data, allows regions of applicability of one-pion exchange to be delineated. The analysis disfavors several models of the pion flux used in the literature, and yields an improved extraction of the pion structure function and its uncertainties at parton momentum fractions in the pion of $4 \\times 10^{-4} \\lesssim x_\\pi \\lesssim 0.05$ at a scale of $Q^2$=10 GeV$^2$. Based on the fit results, we provide estimates for leading proton structure functions in upcoming tagged deep-inelastic scattering experiments at Jefferson Lab on the deuteron with forward protons.

  17. DISE: directed sphere exclusion.

    PubMed

    Gobbi, Alberto; Lee, Man-Ling

    2003-01-01

    The Sphere Exclusion algorithm is a well-known algorithm used to select diverse subsets from chemical-compound libraries or collections. It can be applied with any given distance measure between two structures. It is popular because of the intuitive geometrical interpretation of the method and its good performance on large data sets. This paper describes Directed Sphere Exclusion (DISE), a modification of the Sphere Exclusion algorithm, which retains all positive properties of the Sphere Exclusion algorithm but generates a more even distribution of the selected compounds in the chemical space. In addition, the computational requirement is significantly reduced, thus it can be applied to very large data sets.

  18. Hard exclusive neutral pion production at Jefferson Lab Hall A

    SciTech Connect

    E. Fuchey

    2011-10-01

    We present measurements of the ep {yields} ep{pi}{sup 0} cross section extracted at two values of four-momentum transfer Q{sup 2} = 1.9 GeV{sup 2} and Q{sup 2} = 2.3 GeV{sup 2} at Jefferson Lab Hall A. The kinematic range allows to study the evolution of the cross section as a function of Q{sup 2} and W. Results will be confronted with Regge inspired calculations and GPD predictions. An interpretation of our data within the framework of semi-inclusive deep inelastic scattering has also been attempted.

  19. Hard exclusive neutral pion production at Jefferson Lab Hall A

    SciTech Connect

    Fuchey, E.

    2011-10-24

    We present measurements of the ep{yields}ep{pi}{sup 0} cross section extracted at two values of four-momentum transfer Q{sup 2} = 1.9 GeV{sup 2} and Q{sup 2} = 2.3 GeV{sup 2} at Jefferson Lab Hall A. The kinematic range allows to study the evolution of the cross section as a function of Q{sup 2} and W. Results will be confronted with Regge inspired calculations and GPD predictions. An intepretation of our data within the framework of semi-inclusive deep inelastic scattering has also been attempted.

  20. Model of reversible vesicular transport with exclusion

    NASA Astrophysics Data System (ADS)

    Bressloff, Paul C.; Karamched, Bhargav R.

    2016-08-01

    A major question in neurobiology concerns the mechanics behind the motor-driven transport and delivery of vesicles to synaptic targets along the axon of a neuron. Experimental evidence suggests that the distribution of vesicles along the axon is relatively uniform and that vesicular delivery to synapses is reversible. A recent modeling study has made explicit the crucial role that reversibility in vesicular delivery to synapses plays in achieving uniformity in vesicle distribution, so called synaptic democracy (Bressloff et al 2015 Phys. Rev. Lett. 114 168101). In this paper we generalize the previous model by accounting for exclusion effects (hard-core repulsion) that may occur between molecular motor-cargo complexes (particles) moving along the same microtubule track. The resulting model takes the form of an exclusion process with four internal states, which distinguish between motile and stationary particles, and whether or not a particle is carrying vesicles. By applying a mean field approximation and an adiabatic approximation we reduce the system of ODEs describing the evolution of occupation numbers of the sites on a 1D lattice to a system of hydrodynamic equations in the continuum limit. We find that reversibility in vesicular delivery allows for synaptic democracy even in the presence of exclusion effects, although exclusion does exacerbate nonuniform distributions of vesicles in an axon when compared with a model without exclusion. We also uncover the relationship between our model and other models of exclusion processes with internal states.

  1. Mutually Exclusive Uncertainty Relations

    NASA Astrophysics Data System (ADS)

    Xiao, Yunlong; Jing, Naihuan

    2016-11-01

    The uncertainty principle is one of the characteristic properties of quantum theory based on incompatibility. Apart from the incompatible relation of quantum states, mutually exclusiveness is another remarkable phenomenon in the information- theoretic foundation of quantum theory. We investigate the role of mutual exclusive physical states in the recent work of stronger uncertainty relations for all incompatible observables by Mccone and Pati and generalize the weighted uncertainty relation to the product form as well as their multi-observable analogues. The new bounds capture both incompatibility and mutually exclusiveness, and are tighter compared with the existing bounds.

  2. Mutually Exclusive Uncertainty Relations.

    PubMed

    Xiao, Yunlong; Jing, Naihuan

    2016-11-08

    The uncertainty principle is one of the characteristic properties of quantum theory based on incompatibility. Apart from the incompatible relation of quantum states, mutually exclusiveness is another remarkable phenomenon in the information- theoretic foundation of quantum theory. We investigate the role of mutual exclusive physical states in the recent work of stronger uncertainty relations for all incompatible observables by Mccone and Pati and generalize the weighted uncertainty relation to the product form as well as their multi-observable analogues. The new bounds capture both incompatibility and mutually exclusiveness, and are tighter compared with the existing bounds.

  3. Mutually Exclusive Uncertainty Relations

    PubMed Central

    Xiao, Yunlong; Jing, Naihuan

    2016-01-01

    The uncertainty principle is one of the characteristic properties of quantum theory based on incompatibility. Apart from the incompatible relation of quantum states, mutually exclusiveness is another remarkable phenomenon in the information- theoretic foundation of quantum theory. We investigate the role of mutual exclusive physical states in the recent work of stronger uncertainty relations for all incompatible observables by Mccone and Pati and generalize the weighted uncertainty relation to the product form as well as their multi-observable analogues. The new bounds capture both incompatibility and mutually exclusiveness, and are tighter compared with the existing bounds. PMID:27824161

  4. Omega Electroproduction

    SciTech Connect

    Unwuchola, A. D.; Connell, Simon H.; Aurousseau, M.; Dalton, Mark M.

    2013-08-01

    The differential cross section for p(e, e'ω)p has been studied at Q{sup 2} ~ 5.5 (GeV/c)2. Here Q{sup 2} represents the four momentum squared of the virtual photon in the excitation of baryonic resonances by an electron projectile. In order to extract the ω-meson differential cross section from the JLAB data, the data was compared to a full Monte Carlo simulation of the detector based on events generated for omega production in a way that the production cross section was varied to achieve a match to the data. The bin selected for this procedure takes into account the measure of robustness of the stripping of the ω peak from the multi-pion background as well as the statistics in the measured data and the Monte Carlo simulation of the signal and background physics. An error estimation technique for the cross section was based on determining the dependence of the extracted cross section parameters on the experimental set-up (including parameters for the spectrometer, target beam geometeries and performance). We compare our results with a Regge-based model for hadronic content in the t-channel exchange of a photon in Q{sup 2} region of overlap. There is an extension of this data into a completely new region, which is the highest yet measured.

  5. Precision Measurement of Electroproduction of pi0 near Threshold

    SciTech Connect

    Chirapatpimol, Khem

    2012-05-01

    Electromagnetic production of neutral pions near threshold is the most basic, lowest energy reaction in which a new hadron is created. The electromagnetic interaction is well understood so measurements of this reaction can yield direct insight into the hadronic production mechanism. During the past three decades there have been many developments in both the measurement and theory of threshold pion production, starting with measurements of photo-production at Saclay in 1986 and at Mainz in 1990. These measurements indicated a surprising discrepancy with so-called Low Energy Theorems (LETs) which are based on quite fundamental symmetries and considerations. Chiral Perturbation Theory (ChPT) is an effective field theoretic description of the nuclear force which contains the underlying symmetries of the force but deals with nucleons and pions rather than quarks and gluons. It has the advantage of being applicable at low energies but requires tuning some parameters to experimental data. Once these parameters have been determined ChPT predicts how the reaction should behave as a function of the kinematic variable. When applied to the reaction, p(γ,π0)p, near threshold it explained the discrepancy with the LETs and made predictions for electroproduction, p(e,e'p)π 0. Electroproduction measurements at Mainz in the 1990's showed a clear discrepancy with these predictions of ChPT; with parameters determined from one set of kinematics the data for a second set lay far from the predicted value. However, recently completed measurements at Mainz disagreed with their previous measurements. In the experiment presented here, measurements of neutral pion electroproduction,p(e,e'p)π0, were made in bins of momentum transfer, Q2, between Q2 = 0.05 [GeV/c]2 and Q2 = 0.15 [GeV/c]0 and of center-of-mass energy, W, between 0 ≤ W ≤ 30 MeV (above threshold). The experiment was performed in Hall A

  6. Exclusive processes and the fundamental structure of hadrons

    SciTech Connect

    Brodsky, Stanley J.

    2015-01-20

    I review the historical development of QCD predictions for exclusive hadronic processes, beginning with constituent counting rules and the quark interchange mechanism, phenomena which gave early validation for the quark structure of hadrons. The subsequent development of pQCD factorization theorems for hard exclusive amplitudes and the development of evolution equations for the hadron distribution amplitudes provided a rigorous framework for calculating hadronic form factors and hard scattering exclusive scattering processes at high momentum transfer. I also give a brief introduction to the field of "light-front holography" and the insights it brings to quark confinement, the behavior of the QCD coupling in the nonperturbative domain, as well as hadron spectroscopy and the dynamics of exclusive processes.

  7. Exclusive processes and the fundamental structure of hadrons

    DOE PAGES

    Brodsky, Stanley J.

    2015-01-20

    I review the historical development of QCD predictions for exclusive hadronic processes, beginning with constituent counting rules and the quark interchange mechanism, phenomena which gave early validation for the quark structure of hadrons. The subsequent development of pQCD factorization theorems for hard exclusive amplitudes and the development of evolution equations for the hadron distribution amplitudes provided a rigorous framework for calculating hadronic form factors and hard scattering exclusive scattering processes at high momentum transfer. I also give a brief introduction to the field of "light-front holography" and the insights it brings to quark confinement, the behavior of the QCD couplingmore » in the nonperturbative domain, as well as hadron spectroscopy and the dynamics of exclusive processes.« less

  8. ''Follow that quarkexclamation'' (and other exclusive stories)

    SciTech Connect

    Carroll, A.S.

    1987-06-17

    Quarks are considered to be the basic constituents of matter. In a series of recent experiments, Carroll studied exclusive reactions as a means of determining the interactions between quarks. Quantum Chromo-dynamics (QCD) is the modern theory of the interaction of quarks. This theory explains how quarks are held together via the strong interaction in particles known as hadrons. Hadrons consisting of three quarks are called baryons. Hadrons made up of a quark and an antiquark are called mesons. In his lecture, Carroll describes what happens when two hadrons collide and scatter to large angles. The violence of the collision causes the gluons that bind the quarks in a particular hadron to temporarily lose their grip on particular quarks. Quarks scramble toward renewed unity with other quarks, and they undergo rearrangement, which generally results in additional new particles. A two-body exclusive reaction has occurred when the same number of particles exist before and after the collisions. At large angles these exclusive reactions are very rare. The labels on the quarks known as flavor enable the experimenter to follow the history of individual quarks in detail during these exclusive reactions. Carroll describes the equipment used in the experiment to measure short distance, hard collisions at large angles. The collisions he discusses occur when a known beam of mesons or protons collide with a stationary proton target. Finally, Carroll summarizes what the experiments have shown from the study of exclusive reactions and what light some of their results shed on the theory of QCD.

  9. Single π+ Electroproduction in the First and Second Resonance Regions Using CLAS

    SciTech Connect

    Egiyan, Hovanes

    2001-01-01

    The study of single pion electroproduction can provide valuable information on the structure of the nucleon and its excited states. Although these reactions have been studied for decades, never has the n π+ channel been measured over the complete phase space of the reaction. The CEBAF Large Acceptance Spectrometer (CLAS) located in Hall B of Jefferson Lab is well-suited for conducting these measurements. The CLAS data were taken using a 1.515 GeV electron beam incident on a liquid H2 target. The cross sections have been extracted, and their phi-dependence has been fit to obtain the sigmaTT, sigmaTL and the sigmaT + epsilon sigmaL linear combination of the structure functions. An analysis program based on the Mainz unitary isobar model was used to analyze the experimental data from the π+ channel only. The resonant amplitudes for P33(1232), SL(1535) and D{sub 13}(1520) were obtained from the fit.

  10. Consistent model for πN transition distribution amplitudes and backward pion electroproduction

    NASA Astrophysics Data System (ADS)

    Lansberg, J. P.; Pire, B.; Semenov-Tian-Shansky, K.; Szymanowski, L.

    2012-03-01

    The extension of the concept of generalized parton distributions leads to the introduction of baryon to meson transition distribution amplitudes (TDAs), nondiagonal matrix elements of the nonlocal three quark operator between a nucleon and a meson state. We present a general framework for modeling nucleon to pion (πN) TDAs. Our main tool is the spectral representation for πN TDAs in terms of quadruple distributions. We propose a factorized Ansatz for quadruple distributions with input from the soft-pion theorem for πN TDAs. The spectral representation is complemented with a D-term like contribution from the nucleon exchange in the cross channel. We then study backward pion electroproduction in the QCD collinear factorization approach in which the nonperturbative part of the amplitude involves πN TDAs. Within our two component model for πN TDAs, we update previous leading-twist estimates of the unpolarized cross section. Finally, we compute the transverse target single spin asymmetry as a function of skewness. We find it to be sizable in the valence region and sensitive to the phenomenological input of our πN TDA model.

  11. Measurement of the induced Λ0(1116) polarization in K+ electroproduction at CLAS

    NASA Astrophysics Data System (ADS)

    Gabrielyan, M.; Raue, B.; Carman, D. S.; Park, K.; CLAS Collaboration

    2012-04-01

    We are using the p(e, e' K+p)π- reaction to perform a measurement of the induced polarization of the electroproduced L(1116) using its pπ- parity-violating weak decay. This study uses the CEBAF Large Acceptance Spectrometer (CLAS) to detect the scattered electron, the kaon, and the decay proton over the kinematics 0.8 ≤ Q2 ≤ 3.5 GeV2, 1.6 ≤ W ≤ 3.0 GeV, and the full kaon CM angle range. In this experiment a 5.5 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. The goal is to map out the kinematic dependencies for this polarization observable to provide new constraints for models of the electromagnetic production of K-hyperon final states. Along with previously published photo- and electroproduction cross sections and polarization observables from CLAS, SAPHIR, LEPS, and GRAAL, these data are needed in a coupled-channel analysis to identify previously unobserved s-channel resonances. Preliminary polarization results will be presented.

  12. Study of photon electroproduction on the nucleon at high and low energy by Virtual Compton Scattering

    NASA Astrophysics Data System (ADS)

    Benali, M.; Mazouz, M.; Fonvieille, H.

    2017-01-01

    Virtual Compton Scattering (VCS) and Deeply Virtual Compton Scattering (DVCS) on the nucleon are two processes accessed via the photon electroproduction reaction ( eN → eγ N). In the first part of this paper we are interested by the DVCS on the neutron. We measured the ( D( e, eγ) X- H( e, e'γ) X) unpolarized cross section and we extracted, for the first time, a non-zero contribution of (neutron-DVCS + coherent- deuteron-DVCS) at Q 2 = 1.75 GeV2 and x B = 36 from Jefferson Lab experiment E08-025. VCS on the proton has been studied at Mainz Microtron MAMI at the four-momentum transfer squared Q 2 = 0.5 GeV2, below the pion production threshold. In the second part of this paper we present our preliminary results of the structure functions ( P LL - ( P TT/ɛ)) and P LT, and the electric and magnetic generalized polarizabilities α E ( Q 2) and β M ( Q 2) extracted from this experiment.

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

    SciTech Connect

    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,

    2008-01-01

    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

  14. Pion structure function from leading neutron electroproduction and SU(2) flavor asymmetry

    DOE PAGES

    McKenney, Joshua R.; Sato, Nobuo; Melnitchouk, Wally; ...

    2016-03-07

    In this paper, we examine the efficacy of pion exchange models to simultaneously describe leading neutron electroproduction at HERA and themore » $$\\bar{d}-\\bar{u}$$ flavor asymmetry in the proton. A detailed $$\\chi^2$$ analysis of the ZEUS and H1 cross sections, when combined with constraints on the pion flux from Drell-Yan data, allows regions of applicability of one-pion exchange to be delineated. The analysis disfavors several models of the pion flux used in the literature, and yields an improved extraction of the pion structure function and its uncertainties at parton momentum fractions in the pion of $$4 \\times 10^{-4} \\lesssim x_\\pi \\lesssim 0.05$$ at a scale of $Q^2$=10 GeV$^2$. Also, we provide estimates for leading proton structure functions in upcoming tagged deep-inelastic scattering experiments on the deuteron with forward protons, based on the fit results, at Jefferson Lab.« less

  15. Reaction Mechanism for Forward Pion Electroproduction from π^-/π^+ ratios on the Deuteron

    NASA Astrophysics Data System (ADS)

    Assamagan, Ketevi

    1998-04-01

    for the Charged Pion Form Factor (F_π) Collaboration at the Thomas Jefferson National Accelerator Facility (E93-021). During the F_π experiment, forward pion electroproduction data were acquired on the deuteron for Q^2 = 0.6-1.6 at W = 1.95 for both π^+ and π^-. Measurements were made in Hall C with two beam energies at fixed momentum transfer in order to separate the longitudinal and transverse response functions. The ratio of π^-/π^+ production on the deuteron yields an important test of the reaction mechanism, and most systematic errors cancel in this ratio. Previous results using unseparated cross sections were consistent with pion pole dominance at low -t and s-channel quark knockout at higher -t. Ratios for the separated response functions should make more definitive conclusions possible. The F_π experiment will extract F_π(Q^2) from the pion-pole dominated longitudinal response. Reaction mechanism studies will help us to understand any longitudinal non-pole physics backgrounds which may become important at larger -t. The state of the analysis will be summarized as well as our improving knowledge of the reaction mechanism.

  16. Exclusive production at CMS

    NASA Astrophysics Data System (ADS)

    Khakzad, Mohsen

    2017-03-01

    A search for exclusive or quasi-exclusive γγ → W+W- production, pp → p(∗)W+W-p(∗) → p(∗)μ±e∓p(∗), at √{s }=8 TeV (7 TeV) is reported using data corresponding to an integrated luminosity of 19.7 fb-1 (5.5fb-1), respectively. In this study, we look for any deviations that there might be from the Standard Model, and the results are used to set limits on the Anomalous Quartic Gauge Couplings. We also report a measurement of the exclusive production of pairs of charged pions in proton-proton collisions. The differential cross sections for π+π- pairs as a function of the pion pair invariant mass is measured and compared to several phenomenological predictions.

  17. Mutually Exclusive, Complementary, or . . .

    ERIC Educational Resources Information Center

    Schloemer, Cathy G.

    2016-01-01

    Whether students are beginning their study of probability or are well into it, distinctions between complementary sets and mutually exclusive sets can be confusing. Cathy Schloemer writes in this article that for years she used typical classroom examples but was not happy with the student engagement or the level of understanding they produced.…

  18. Generalized parton distributions and exclusive processes

    SciTech Connect

    Guzey, Vadim

    2013-10-01

    In last fifteen years, GPDs have emerged as a powerful tool to reveal such aspects of the QCD structure of the nucleon as: - 3D parton correlations and distributions; - spin content of the nucleon. Further advances in the field of GPDs and hard exclusive processes rely on: - developments in theory and new methods in phenomenology such as new flexible parameterizations, neural networks, global QCD fits - new high-precision data covering unexplored kinematics: JLab at 6 and 12 GeV, Hermes with recoil detector, Compass, EIC. This slide-show presents: Nucleon structure in QCD, particularly hard processes, factorization and parton distributions; and a brief overview of GPD phenomenology, including basic properties of GPDs, GPDs and QCD structure of the nucleon, and constraining GPDs from experiments.

  19. Electroproduction of the Φ(1020) Vector Meson at 4 GeV

    SciTech Connect

    Loukachine, Konstantin

    2000-02-01

    We studied the reaction ep → e'p'Φ with a 4.2 GeV incident electron beam in the region of the electroproduction variables Q2 from 0.7 to 2.2 GeV2 and W from 2.0 to 2.6 GeV. The data were taken and analyzed at the Thomas Jefferson National Accelerator Facility. For the first time, we observe the expected t-slope dependence on Q2 and Δτ in Φ vector meson production. We find that the width of the forward Φ-meson diffraction peak increases rapidly as the interaction time decreases below cΔτ of 1 fm. Within a simple optical model framework, the data show that Φ meson has a smaller size than the ρ. The measured Φ cross-section dependence on Q2 is in a good agreement with previous measurements and well-described by the phenomenological Pomeron exchange model. Our cross-section data do not favor the standard Vector Meson Dominance and s$\\bar{s}$-knockout model predictions. From the angular distribution of the decay Φ → K+ K-, assuming the s-channel helicity conservation, we extracted the longitudinal-to-transverse cross-section ratio, R, and Vector Meson Dominance scaling parameter, ζ2, which are consistent with the previous measurements and the model expectations.

  20. Measurement of the Double Spin Asymmetry in π- Electroproduction with CLAS

    SciTech Connect

    Bektasoglu, Mehmet

    2002-12-01

    The double spin asymmetry σet/ σ0 has been measured in π- electro-production using a polarized electron beam and a polarized ND3 target, and using a CEBAF Large Acceptance Spectrometer (CLAS). The electron beam was polarized using a GaAs-cathode and the target was polarized via Dynamic Nuclear Polarization. The beam polarization was around 70% and the target polarization was between 10 and 20 percent. The data at 2.5 GeV beam energy and two different magnetic field settings (2250 A and -1500 A) were collected in Hall B at Jefferson Lab in the Fall of 1998. The eπ- channel was selected using the missing mass technique and applying a cut around the proton peak (0.78 GeV2 < MM2 < 0.95 GeV2). The asymmetry (A1 + ηA2)/(1+ϵR), where both A1 and A2 depend on θ*, has been extracted as a function of the invariant mass W for two Q2 (four-momentum-transfer-squared) bins (0.08 GeV2 < Q2 < 0.4 GeV2 and 0.4 GeV2 < Q2 < 1.2 GeV2). The results were integrated over the angular acceptance of the channel as well as for a narrower range in θ* (0.17 < cosθ* < 1). The data have been compared to two phenomenological models, MAID and AO.

  1. Social exclusion in finite populations

    NASA Astrophysics Data System (ADS)

    Li, Kun; Cong, Rui; Wu, Te; Wang, Long

    2015-04-01

    Social exclusion, keeping free riders from benefit sharing, plays an important role in sustaining cooperation in our world. Here we propose two different exclusion regimes, namely, peer exclusion and pool exclusion, to investigate the evolution of social exclusion in finite populations. In the peer exclusion regime, each excluder expels all the defectors independently, and thus bears the total cost on his own, while in the pool exclusion regime, excluders spontaneously form an institution to carry out rejection of the free riders, and each excluder shares the cost equally. In a public goods game containing only excluders and defectors, it is found that peer excluders outperform pool excluders if the exclusion costs are small, and the situation is converse once the exclusion costs exceed some critical points, which holds true for all the selection intensities and different update rules. Moreover, excluders can dominate the whole population under a suitable parameters range in the presence of second-order free riders (cooperators), showing that exclusion has prominent advantages over common costly punishment. More importantly, our finding indicates that the group exclusion mechanism helps the cooperative union to survive under unfavorable conditions. Our results may give some insights into better understanding the prevalence of such a strategy in the real world and its significance in sustaining cooperation.

  2. Ordering of hard particles between hard walls

    NASA Astrophysics Data System (ADS)

    Chrzanowska, A.; Teixeira, P. I. C.; Ehrentraut, H.; Cleaver, D. J.

    2001-05-01

    The structure of a fluid of hard Gaussian overlap particles of elongation κ = 5, confined between two hard walls, has been calculated from density-functional theory and Monte Carlo simulations. By using the exact expression for the excluded volume kernel (Velasco E and Mederos L 1998 J. Chem. Phys. 109 2361) and solving the appropriate Euler-Lagrange equation entirely numerically, we have been able to extend our theoretical predictions into the nematic phase, which had up till now remained relatively unexplored due to the high computational cost. Simulation reveals a rich adsorption behaviour with increasing bulk density, which is described semi-quantitatively by the theory without any adjustable parameters.

  3. Exclusion processes with avalanches.

    PubMed

    Bhat, Uttam; Krapivsky, P L

    2014-07-01

    In an exclusion process with avalanches, when a particle hops to a neighboring empty site which is adjacent to an island the particle on the other end of the island immediately hops, and if it joins another island this triggers another hop. There are no restrictions on the length of the islands and the duration of the avalanche. This process is well defined in the low-density region ρ < 1/2. We describe the nature of steady states (on a ring) and determine all correlation functions. For the asymmetric version of the process, we compute the steady state current, and we describe shock and rarefaction waves which arise in the evolution of the step-function initial profile. For the symmetric version, we determine the diffusion coefficient and examine the evolution of a tagged particle.

  4. Exclusion performance and learning by exclusion in dogs.

    PubMed

    Zaine, Isabela; Domeniconi, Camila; de Rose, Julio C

    2016-05-01

    Responding by exclusion is a type of emergent repertoire in which an individual chooses an alternative by the apparent exclusion of other available alternatives. In this case it is possible to respond appropriately to an undefined stimulus (one that has not previously acquired discriminative functions) by excluding the defined alternatives. There is evidence of exclusion in humans and nonhuman animals, although learning as an outcome of exclusion does not always occur. This study aimed to investigate exclusion in visual simple discriminations and learning of new simple discriminations resulting from exclusion in four border collies. Subjects were trained to perform simple simultaneous discriminations between pairs of tridimensional objects, and were then tested for exclusion, novelty control and learning of new simple discriminations. All dogs successfully responded by exclusion, choosing an undefined stimulus displayed with an S-. For three dogs, it was possible to conclude that these previously undefined stimuli acquired S+ functions, documenting learning of new simple discriminations. However, this required up to four exposures to exclusion trials with each pair of stimuli.

  5. Hardness Tester for Polyur

    NASA Technical Reports Server (NTRS)

    Hauser, D. L.; Buras, D. F.; Corbin, J. M.

    1987-01-01

    Rubber-hardness tester modified for use on rigid polyurethane foam. Provides objective basis for evaluation of improvements in foam manufacturing and inspection. Typical acceptance criterion requires minimum hardness reading of 80 on modified tester. With adequate correlation tests, modified tester used to measure indirectly tensile and compressive strengths of foam.

  6. Session: Hard Rock Penetration

    SciTech Connect

    Tennyson, George P. Jr.; Dunn, James C.; Drumheller, Douglas S.; Glowka, David A.; Lysne, Peter

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hard Rock Penetration - Summary'' by George P. Tennyson, Jr.; ''Overview - Hard Rock Penetration'' by James C. Dunn; ''An Overview of Acoustic Telemetry'' by Douglas S. Drumheller; ''Lost Circulation Technology Development Status'' by David A. Glowka; ''Downhole Memory-Logging Tools'' by Peter Lysne.

  7. Hard Photodisintegration of Proton Pairs in {sup 3}He

    SciTech Connect

    Piasetzky, Eli; Pomerantz, Ishay; Higinbotham, D.; Strauch, S.; Gilman, R.

    2008-10-13

    Hard deuteron photodisintegration has been investigated for 20 years, as its cross section follows the constituent counting rule and it provides insight into the interplay between hadronic and quark-gluon degrees of freedom in high-momentum transfer exclusive reactions. We have now measured for the first time hard pp-pair disintegration in the reaction {gamma}{sup 3}He{yields}pp+n, using kinematics corresponding to a spectator neutron. Cross sections were measured for 90 deg. c.m. at 8 beam energies, from 0.8 to 4.7 GeV. Preliminary results will be presented and compared to the hard deuteron photodisintegration data.

  8. Exclusive Processes in Quantum Chromodynamics

    NASA Astrophysics Data System (ADS)

    Brodsky, Stanley J.; Peter Lepage, G.

    The following sections are included: * INTRODUCTION * NONRELATIVISTIC FORM FACTORS FOR HEAVY-QUARK MESONS * HADRONIC WAVEFUNCTIONS * DEFINITIONS * LIGHT-CONE BOUND-STATE EQUATIONS * GENERAL PROPERTIES OF LIGHT-CONE WAVEFUNCTIONS * RENORMALIZATION * CALCULATING * A PERTURBATIVE ANALYSIS * FACTORIZATION—LEADING ORDER ANALYSIS * THE QUARK DISTRIBUTION AMPLITUDE * DETERMINATION OF DISTRIBUTION AMPLITUDES * HIGHER ORDER ANALYSIS * COMPLICATIONS * How LARGE IS ASYMPTOTIC Q? * APPLICATIONS OF QCD TO THE PHENOMENOLOGY OF EXCLUSIVE REACTIONS * GENERAL FEATURES OF EXCLUSIVE PROCESSES IN QCD * ELECTROMAGNETIC FORM FACTORS * COMPARISON OF QCD SCALING WITH EXPERIMENT * EXCLUSIVE ANTI-PROTON PROTON ANNIHILATION PROCESSES * ADDITIONAL TESTS OF GLUON SPIN IN EXCLUSIVE PROCESSES * HADRONIC WAVEFUNCTION PHENOMENOLOGY * CALCULATING TH * THE PRE-QCD DEVELOPMENT OF EXCLUSIVE REACTIONS * EXCLUSIVE e+ e- ANNIHILATION PROCESSES * J/ψ DECAY TO HADRON PAIRS * THE π-ρ PUZZLE * FORM FACTOR ZEROS IN QCD * EXCLUSIVE γγ REACTIONS * QCD PROCESSES IN NUCLEI * EXCLUSIVE NUCLEAR REACTIONS - REDUCED AMPLITUDES * COLOR TRANSPARENCY * SPIN CORRELATIONS IN PROTON-PROTON SCATTERING * CONCLUSIONS * APPENDIX I BARYON FORM FACTORS AND EVOLUTION EQUATIONS * APPENDIX II LIGHT CONE QUANTIZATION AND PERTURBATION THEORY * APPENDIX III A NONPERTURBATIVE ANALYSIS OF EXCLUSIVE REACTIONS-DISCRETIZED LIGHT-CONE QUANTIZATION * ACKNOWLEDGEMENTS * REFERENCES

  9. Hard diffractive results and prospects at the Tevatron

    SciTech Connect

    Peters, Krisztian; /Manchester U.

    2006-01-01

    We review hard diffractive results and prospects at the Tevatron with an emphasis on factorization breaking in diffractive processes. Upper limits on the exclusive di-jet and {chi}{sub c}{sup 0} production cross sections at CDF and the status of the D0 Forward Proton Detectors are discussed.

  10. Exact results for the one dimensional asymmetric exclusion model

    NASA Astrophysics Data System (ADS)

    Derrida, B.; Evans, M. R.; Hakim, V.; Pasquier, V.

    1993-11-01

    The asymmetric exclusion model describes a system of particles hopping in a preferred direction with hard core repulsion. These particles can be thought of as charged particles in a field, as steps of an interface, as cars in a queue. Several exact results concerning the steady state of this system have been obtained recently. The solution consists of representing the weights of the configurations in the steady state as products of non-commuting matrices.

  11. Deeply exclusive processes and generalized parton distributions

    SciTech Connect

    Marc Vanderhaegen

    2005-02-01

    We discuss how generalized parton distributions (GPDs) enter into hard exclusive processes, and focuses on the links between GPDs and elastic nucleon form factors. These links, in the form of sum rules, represent powerful constraints on parameterizations of GPDs. A Regge parameterization for the GPDs at small momentum transfer -t is extended to the large-t region and it is found to catch the basic features of proton and neutron electromagnetic form factor data. This parameterization allows to estimate the quark contribution to the nucleon spin. It is furthermore discussed how these GPDs at large-t enter into two-photon exchange processes and resolve the discrepancy between Rosenbluth and polarization experiments of elastic electron nucleon scattering.

  12. Diffractive and exclusive measurements at CDF

    SciTech Connect

    Gallinaro, Michele; /Rockefeller U.

    2006-06-01

    Experimental results from the CDF experiment at the Tevatron in p{bar p} collisions at {radical}s = 1.96 TeV are presented on the diffractive structure function at different values of the exchanged momentum transfer squared in the range 0 < Q{sup 2} < 10,000 GeV{sup 2}, on the four-momentum transfer |t| distribution in the region 0 < |t| < 1 GeV{sup 2} for both soft and hard diffractive events up to Q{sup 2} {approx} 4,500 GeV{sup 2}, and on the first experimental evidence of exclusive production in both dijet and diphoton events. A novel technique to align the Roman Pot detectors is also presented.

  13. Dynamic hardness of metals

    NASA Astrophysics Data System (ADS)

    Liang, Xuecheng

    Dynamic hardness (Pd) of 22 different pure metals and alloys having a wide range of elastic modulus, static hardness, and crystal structure were measured in a gas pulse system. The indentation contact diameter with an indenting sphere and the radius (r2) of curvature of the indentation were determined by the curve fitting of the indentation profile data. r 2 measured by the profilometer was compared with that calculated from Hertz equation in both dynamic and static conditions. The results indicated that the curvature change due to elastic recovery after unloading is approximately proportional to the parameters predicted by Hertz equation. However, r 2 is less than the radius of indenting sphere in many cases which is contradictory to Hertz analysis. This discrepancy is believed due to the difference between Hertzian and actual stress distributions underneath the indentation. Factors which influence indentation elastic recovery were also discussed. It was found that Tabor dynamic hardness formula always gives a lower value than that directly from dynamic hardness definition DeltaE/V because of errors mainly from Tabor's rebound equation and the assumption that dynamic hardness at the beginning of rebound process (Pr) is equal to kinetic energy change of an impact sphere over the formed crater volume (Pd) in the derivation process for Tabor's dynamic hardness formula. Experimental results also suggested that dynamic to static hardness ratio of a material is primarily determined by its crystal structure and static hardness. The effects of strain rate and temperature rise on this ratio were discussed. A vacuum rotating arm apparatus was built to measure Pd at 70, 127, and 381 mum sphere sizes, these results exhibited that Pd is highly depended on the sphere size due to the strain rate effects. P d was also used to substitute for static hardness to correlate with abrasion and erosion resistance of metals and alloys. The particle size effects observed in erosion were

  14. Inference by Exclusion in Goffin Cockatoos (Cacatua goffini)

    PubMed Central

    O’Hara, Mark; Auersperg, Alice M. I.; Bugnyar, Thomas; Huber, Ludwig

    2015-01-01

    Inference by exclusion, the ability to base choices on the systematic exclusion of alternatives, has been studied in many nonhuman species over the past decade. However, the majority of methodologies employed so far are hard to integrate into a comparative framework as they rarely use controls for the effect of neophilia. Here, we present an improved approach that takes neophilia into account, using an abstract two-choice task on a touch screen, which is equally feasible for a large variety of species. To test this approach we chose Goffin cockatoos (Cacatua goffini), a highly explorative Indonesian parrot species, which have recently been reported to have sophisticated cognitive skills in the technical domain. Our results indicate that Goffin cockatoos are able to solve such abstract two-choice tasks employing inference by exclusion but also highlight the importance of other response strategies. PMID:26244692

  15. Organizing Your Hard Disk.

    ERIC Educational Resources Information Center

    Stocker, H. Robert; Hilton, Thomas S. E.

    1991-01-01

    Suggests strategies that make hard disk organization easy and efficient, such as making, changing, and removing directories; grouping files by subject; naming files effectively; backing up efficiently; and using PATH. (JOW)

  16. Radiation from hard objects

    SciTech Connect

    Canavan, G.H.

    1997-02-01

    The inference of the diameter of hard objects is insensitive to radiation efficiency. Deductions of radiation efficiency from observations are very sensitive - possibly overly so. Inferences of the initial velocity and trajectory vary similarly, and hence are comparably sensitive.

  17. Measurement of the photon electroproduction cross section at JLAB with the goal of performing a Rosenbluth separation of the DVCS contribution

    SciTech Connect

    Jimenez-Arguello, Alejandro Marti

    2014-07-11

    The study of the inner structure of hadrons allows us to understand the nature of the interactions between partons, quarks and gluons, described by Quantum Chromodynamics. The elastic scattering reactions, which have been studied in order to measure the nucleon form factors, are included in this frame. The inelastic scattering reactions are also included in this frame, they allow us to obtain information about the nucleon structure thanks to the development of the parton distribution functions (PDFs). While through elastic scattering we can obtain information about the charge distribution of the nucleon, and hence, about the spatial distribution of the partons, through inelastic scattering we obtain information about the momentum distributions of partons, by employing the PDFs. However, we can study the exclusive inelastic scattering reactions, such as the Deeply Virtual Compton Scattering (DVCS), wich allow us to access to the spatial and momentum distributions simultaneously. This is possible thanks to the generalized parton distributions (GPDs), which allow us to correlate both types of distributions. The process known as DVCS is the easiest way to access the GPDs. This process can be expressed as the scattering of an electron by a proton by means of a virtual photon with the result of the scattered initial particles plus a real photon. We find a process competing with DVCS known as Bethe-Heitler (BH), in which the real photon is radiated by the lepton rather than the quark. Due to the small cross section of DVCS, of the order of nb, in order to conduct these kind of experiments it is necessary to make use of facilities capable of providing high beam intensities. One of these facilities is the Thomas Jefferson National Accelerator Facility , where the experiment JLab E07-007, "Complete Separation of Virtual Photon and π⁰ Electroproduction Observables of Unpolarized Protons", took place during the months of October to December of 2010. The main goal of this

  18. Budgeting in Hard Times.

    ERIC Educational Resources Information Center

    Parrino, Frank M.

    2003-01-01

    Interviews with school board members and administrators produced a list of suggestions for balancing a budget in hard times. Among these are changing calendars and schedules to reduce heating and cooling costs; sharing personnel; rescheduling some extracurricular activities; and forming cooperative agreements with other districts. (MLF)

  19. Running in Hard Times

    ERIC Educational Resources Information Center

    Berry, John N., III

    2009-01-01

    Roberta Stevens and Kent Oliver are campaigning hard for the presidency of the American Library Association (ALA). Stevens is outreach projects and partnerships officer at the Library of Congress. Oliver is executive director of the Stark County District Library in Canton, Ohio. They have debated, discussed, and posted web sites, Facebook pages,…

  20. CSI: Hard Drive

    ERIC Educational Resources Information Center

    Sturgeon, Julie

    2008-01-01

    Acting on information from students who reported seeing a classmate looking at inappropriate material on a school computer, school officials used forensics software to plunge the depths of the PC's hard drive, searching for evidence of improper activity. Images were found in a deleted Internet Explorer cache as well as deleted file space.…

  1. Induced Proton Polarization for pi0 Electroproduction at Q2 = 0.126 GeV2/c2 Around the Delta(1232) Resonance

    SciTech Connect

    Glen Warren; Ricardo Alarcon; Christopher Armstrong; Burin Asavapibhop; David Barkhuff; William Bertozzi; Volker Burkert; J. Chen; Jian-Ping Chen; Joseph Comfort; Daniel Dale; George Dodson; S. Dolfini; K. Dow; Martin Epstein; Manouchehr Farkhondeh; John Finn; Shalev Gilad; Ralf Gothe; Xiaodong Jiang; Mark Jones; Kyungseon Joo; A. Karabarbounis; James Kelly; Stanley Kowalski; C. Kunz; D. Liu; R.W. Lourie; Richard Madey; Demetrius Margaziotis; Pete Markowitz; Justin McIntyre; C. Mertz; Brian Milbrath; Rory Miskimen; Joseph Mitchell; S. Mukhopadhyay; Costas Papanicolas; Charles Perdrisat; Vina Punjabi; Liming Qin; Paul Rutt; Adam Sarty; Jeffrey Shaw; S.B. Soong; D. Tieger; Christoph Tschalaer; William Turchinetz; Paul Ulmer; Scott Van Verst; C. Vellidis; Lawrence Weinstein; Steven Williamson; Rhett Woo; Alaen Young

    1998-12-01

    We present a measurement of the induced proton polarization P{sub n} in {pi}{sup 0} electroproduction on the proton around the {Delta} resonance. The measurement was made at a central invariant mass and a squared four-momentum transfer of W = 1231 MeV and Q{sup 2} = 0.126 GeV{sup 2}/c{sup 2}, respectively. We measured a large induced polarization, P{sub n} = -0.397 {+-} 0.055 {+-} 0.009. The data suggest that the scalar background is larger than expected from a recent effective Hamiltonian model.

  2. Electroproduction of the S{sub 11}(1535) resonance at high momentum transfer

    SciTech Connect

    Bosted, P.; Armstrong, C.S.; Meekins, D.; Ahmidouch, A.; Assamagan, K.; Avery, S.; Baker, O.K.; Eden, T.; Gaskell, D.; Gueye, P.; Hinton, W.; Keppel, C.; Madey, R.; Niculescu, G.; Niculescu, I.; Tang, L.; Ahmidouch, A.; Madey, R.; Kim, W.; Stoler, P.; Adams, G.S.; Frolov, V.V.; Klusman, M.; Napolitano, J.; Nozar, M.; Price, J.W.; Witkowski, M.; Baker, O.K.; Burkert, V.; Carlini, R.; Dunne, J.; Ent, R.; Keppel, C.; Mack, D.; Mitchell, J.; Tang, L.; Wood, S.; Koltenuk, D.; Minehart, R.

    1999-09-01

    The differential cross section for the process p(e,e{sup {prime}}p){eta} has been measured at Q{sup 2}=2.4 and 3.6 (GeV/c){sup 2} at center-of-mass energies encompassing the S{sub 11}(1535) resonance. The latter point is the highest-Q{sup 2} exclusive measurement of this process to date. The resonance width and the helicity-1/2 transition amplitude are extracted from the data, and evidence for the possible onset of scaling in this reaction is shown. A lower bound of {approx}0.45 is placed on the S{sub 11}(1535){r_arrow}p{eta} branching fraction. {copyright} {ital 1999} {ital The American Physical Society}

  3. Electroproduction of Eta Mesons in the S11(1535) Resonance Region at High Momentum Transfer

    SciTech Connect

    Dalton, Mark; Adams, Gary; Ahmidouch, Abdellah; Angelescu, Tatiana; Arrington, John; Asaturyan, Razmik; Baker, Keith; Benmouna, Nawal; Bertoncini, Crystal; Boeglin, Werner; Bosted, Peter; Breuer, Herbert; Christy, Michael; Connell, S.; Cui, Y.; Danagoulian, Samuel; Day, Donal; Dodario, T.; Dunne, James; Dutta, Dipangkar; Khayari, N.El; Ent, R.; Fenker, Howard; Frolov, Valera; Gan, Liping; Gaskell, David; Hafidi, Kawtar; Hinton, Wendy; Holt, Roy; Horn, Tanja; Huber, Garth; Hungerford, Ed; Jiang, Xiaodong; Jones, Mark; Joo, Kyungseon; Kalantarians, Narbe; Kelly, J.J.; Keppel, Cynthia; Koubarovski, Valeri; Kubarovsky, Valery; Kubarovsky, Valery; Kubarovsky, Valery; Li, Y.; Liang, Y.; Malace, S.; Markowitz, Pete; McKee, Paul; Meekins, David; Mkrtchyan, Hamlet; Moziak, B.; Navasardyan, Tigran; Niculescu, Gabriel; Niculescu, Maria-Ioana; Opper, Allena; Ostapenko, Tanya; Reimer, Paul; Reinhold, Joerg; Roche, Julie; ROCK, S.E.; Schulte, Elaine; Segbefia, Edwin; Smith, C.; Smith, Gregory; Stoler, Paul; Tadevosyan, Vardan; Tang, Liguang; Tvaskis, Vladas; Ungaro, Maurizio; Uzzle, Alicia; Vidakovic, S.; Villano, A.; Vulcan, William; WANG, M.; Warren, Glen; Wesselmann, Frank; Wojtsekhowski, Bogdan; Wood, Stephen; Xu, C.; Yuan, Lulin; Zheng, Xiaochao; Guo Zhu, Hong

    2009-01-01

    The differential cross-section for the process p(e,e'p)eta has been measured at Q2 ~ 5.7 and 7.0 (GeV/c)2 for centre-of-mass energies from threshold to 1.8 GeV, encompassing the S11(1535) resonance, which dominates the channel. This is the highest momentum transfer measurement of this exclusive process to date. The helicity-conserving transition amplitude A_1/2, for the production of the S11(1535) resonance, is extracted from the data. This quantity appears to begin scaling as 1/Q3, a predicted signal of the dominance of perturbative QCD, at Q2 ~ 5 (GeV/c)2.

  4. High-Resolution Spectroscopy of {sub L}AMBDA{sup 16}N by Electroproduction

    SciTech Connect

    Cusanno, F.; Urciuoli, G. M.; Acha, A.; Ambrozewicz, P.; Boeglin, W. U.; Coman, L.; Markowitz, P.; Moteabbed, M.; Raue, B.; Reinhold, J.; Aniol, K. A.; Margaziotis, D. J.; Baturin, P.; Jiang, X.; McCormick, K.; Bertin, P. Y.; Camsonne, A.; Ferdi, C.; Blomqvist, K. I.

    2009-11-13

    An experimental study of the {sup 16}O(e,e{sup '}K{sup +}){sub L}AMBDA{sup 16}N reaction has been performed at Jefferson Lab. A thin film of falling water was used as a target. This permitted a simultaneous measurement of the p(e,e{sup '}K{sup +})LAMBDA,SIGMA{sup 0} exclusive reactions and a precise calibration of the energy scale. A ground-state binding energy of 13.76+-0.16 MeV was obtained for {sub L}AMBDA{sup 16}N with better precision than previous measurements on the mirror hypernucleus {sub L}AMBDA{sup 16}O. Precise energies have been determined for peaks arising from a LAMBDA in s and p orbits coupled to the p{sub 1/2} and p{sub 3/2} hole states of the {sup 15}N core nucleus.

  5. Unemployment: Hard-Core or Hard-Shell?

    ERIC Educational Resources Information Center

    Lauer, Robert H.

    1972-01-01

    The term hard-core'' makes the unemployed culpable; the term hard shell'' shifts the burden to the employer, and the evidence from the suburban plant indicates that a substantial part of the problem must lie there. (DM)

  6. Super-Hard Superconductivity

    NASA Astrophysics Data System (ADS)

    Adams, Philip; Prozorov, Ruslan

    2005-03-01

    We present the magnetic response of Type-II superconductivity in the extreme pinning limit, where screening currents within an order of magnitude of the Ginzburg-Landau depairing critical current density develop upon the application of a magnetic field. We show that this ``super-hard'' limit is well approximated in highly disordered, cold drawn, Nb wire whose magnetization response is characterized by a cascade of Meissner-like phases, each terminated by a catastrophic collapse of the magnetization. Direct magneto-optic measurements of the flux penetration depth in the virgin magnetization branch are in excellent agreement with the exponential model in which Jc(B)=Jco(-B/Bo), where Jco˜5x10^6 A/cm^2 for Nb. The implications for the fundamental limiting hardness of a superconductor will be discussed.

  7. 47 CFR 76.107 - Exclusivity contracts.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Exclusivity contracts. 76.107 Section 76.107... § 76.107 Exclusivity contracts. A distributor or television station exercising exclusivity pursuant to... exclusivity contracts, such portions to be signed by both the distributor and the television station,...

  8. Inclusive and Exclusive Compton Processes in Quantum Chromodynamics

    SciTech Connect

    Psaker, Ales

    2005-12-01

    In our work, we describe two types of Compton processes. As an example of an inclusive process, we consider the high-energy photoproduction of massive muon pairs off the nucleon. We analyze the process in the framework of the QCD parton model, in which the usual parton distributions emerge as a tool to describe the nucleon in terms of quark and gluonic degrees of freedom. To study its exclusive version, a new class of phenomenological functions is required, namely, generalized parton distributions. They can be considered as a generalization of the usual parton distributions measured in deeply inelastic lepton-nucleon scattering. Generalized parton distributions (GPDs) may be observed in hard exclusive reactions such as deeply virtual Compton scattering. We develop an extension of this particular process into the weak interaction sector. We also investigate a possible application of the GPD formalism to wide-angle real Compton scattering.

  9. Electroproduction of Photons and of Pawns on the Proton in Quadrimoment of Transfer Q2=1.0GeV2. Measure Cross Sections and Extraction of Polarizabilities Generalities; Electroproduction de Photons et de Pions sur le Proton au Quadrimoment de Transfert Q2=1.0GeV2. Mesure des Sections Efficaces et Extraction des Polarisabilites Generalisees

    SciTech Connect

    Laveissiere, Geraud

    2001-11-06

    In hadronic physics, the nucleon structure and the quarks confinement are still topical issues. The neutral pion electroproduction and virtual Compton scattering (VCS) reactions allow us to access new observables that describe this structure. This work is focused on the VCS experiment performed at Jefferson Lab in 1998.

  10. Exclusive processes in quantum chromodynamics

    SciTech Connect

    Brodsky, S.J.; Lepage, G.P.

    1981-06-01

    Large momentum transfer exclusive processes and the short distance structure of hadronic wave functions can be systematically analyzed within the context of perturbative QCD. Predictions for meson form factors, two-photon processes ..gamma gamma.. ..-->.. M anti M, hadronic decays of heavy quark systems, and a number of other related QCD phenomena are reviewed.

  11. University Ranking as Social Exclusion

    ERIC Educational Resources Information Center

    Amsler, Sarah S.; Bolsmann, Chris

    2012-01-01

    In this article we explore the dual role of global university rankings in the creation of a new, knowledge-identified, transnational capitalist class and in facilitating new forms of social exclusion. We examine how and why the practice of ranking universities has become widely defined by national and international organisations as an important…

  12. Rosenbluth Separation of the π0 Electroproduction Cross Section

    SciTech Connect

    Defurne, M.; Mazouz, M.; Ahmed, Z.; Albataineh, H.; Allada, K.; Aniol, K. A.; Bellini, V.; Benali, M.; Boeglin, W.; Bertin, P.; Brossard, M.; Camsonne, A.; Canan, M.; Chandavar, S.; Chen, C.; Chen, J. -P.; de Jager, C. W.; de Leo, R.; Desnault, C.; Deur, A.; El Fassi, L.; Ent, R.; Flay, D.; Friend, M.; Fuchey, E.; Frullani, S.; Garibaldi, F.; Gaskell, D.; Giusa, A.; Glamazdin, O.; Golge, S.; Gomez, J.; Hansen, O.; Higinbotham, D.; Holmstrom, T.; Horn, T.; Huang, J.; Huang, M.; Huber, G. M.; Hyde, C. E.; Iqbal, S.; Itard, F.; Kang, Ho.; Kang, Hy.; Kelleher, A.; Keppel, C.; Koirala, S.; Korover, I.; LeRose, J. J.; Lindgren, R.; Long, E.; Magne, M.; Mammei, J.; Margaziotis, D. J.; Markowitz, P.; Martí Jiménez-Argüello, A.; Meddi, F.; Meekins, D.; Michaels, R.; Mihovilovic, M.; Muangma, N.; Muñoz Camacho, C.; Nadel-Turonski, P.; Nuruzzaman, N.; Paremuzyan, R.; Puckett, A.; Punjabi, V.; Qiang, Y.; Rakhman, A.; Rashad, M. N. H.; Riordan, S.; Roche, J.; Russo, G.; Sabatié, F.; Saenboonruang, K.; Saha, A.; Sawatzky, B.; Selvy, L.; Shahinyan, A.; Sirca, S.; Solvignon, P.; Sperduto, M. L.; Subedi, R.; Sulkosky, V.; Sutera, C.; Tobias, W. A.; Urciuoli, G. M.; Wang, D.; Wojtsekhowski, B.; Yao, H.; Ye, Z.; Zana, L.; Zhan, X.; Zhang, J.; Zhao, B.; Zhao, Z.; Zheng, X.; Zhu, P.

    2016-12-01

    We present deeply virtual $\\pi^0$ electroproduction cross-section measurements at $x_B$=0.36 and three different $Q^2$--values ranging from 1.5 to 2 GeV$^2$, obtained from experiment E07-007 that ran in the Hall A at Jefferson Lab. The Rosenbluth technique was used to separate the longitudinal and transverse responses. Results demonstrate that the cross section is dominated by its transverse component, and thus is far from the asymptotic limit predicted by perturbative Quantum Chromodynamics. An indication of a non-zero longitudinal contribution is provided by the interference term $\\sigma_{LT}$ also measured. Results are compared with several models based on the leading twist approach of Generalized Parton Distributions (GPDs). In particular, a fair agreement is obtained with models where the scattering amplitude is described by a convolution of chiral-odd (transversity) GPDs of the nucleon with the twist-3 pion distribution amplitude. Therefore, neutral pion electroproduction may offer the exciting possibility of accessing transversity GPDs through experiment.

  13. Hard metal composition

    DOEpatents

    Sheinberg, H.

    1983-07-26

    A composition of matter having a Rockwell A hardness of at least 85 is formed from a precursor mixture comprising between 3 and 10 wt % boron carbide and the remainder a metal mixture comprising from 70 to 90% tungsten or molybdenum, with the remainder of the metal mixture comprising nickel and iron or a mixture thereof. The composition has a relatively low density of between 7 and 14 g/cc. The precursor is preferably hot pressed to yield a composition having greater than 100% of theoretical density.

  14. Hard metal composition

    DOEpatents

    Sheinberg, Haskell

    1986-01-01

    A composition of matter having a Rockwell A hardness of at least 85 is formed from a precursor mixture comprising between 3 and 10 weight percent boron carbide and the remainder a metal mixture comprising from 70 to 90 percent tungsten or molybdenum, with the remainder of the metal mixture comprising nickel and iron or a mixture thereof. The composition has a relatively low density of between 7 to 14 g/cc. The precursor is preferably hot pressed to yield a composition having greater than 100% of theoretical density.

  15. Intrapersonal and interpersonal processes of social exclusion

    PubMed Central

    Kawamoto, Taishi; Ura, Mitsuhiro; Nittono, Hiroshi

    2015-01-01

    People have a fundamental need to belong with others. Social exclusion impairs this need and has various effects on cognition, affect, and the behavior of excluded individuals. We have previously reported that activity in the dorsal anterior cingulate cortex (dACC) and right ventrolateral prefrontal cortex (rVLPFC) could be a neurocognitive index of social exclusion (Kawamoto et al., 2012). In this article, we provide an integrative framework for understanding occurrences during and after social exclusion, by reviewing neuroimaging, electrophysiological, and behavioral studies of dACC and rVLPFC, within the framework of intrapersonal and interpersonal processes of social exclusion. As a result, we have indicated directions for future studies to further clarify the phenomenon of social exclusion from the following perspectives: (1) constructional elements of social exclusion, (2) detection sensitivity and interpretation bias in social exclusion, (3) development of new methods to assess the reactivity to social exclusion, and (4) sources of social exclusion. PMID:25798081

  16. Hard Metal Disease

    PubMed Central

    Bech, A. O.; Kipling, M. D.; Heather, J. C.

    1962-01-01

    In Great Britain there have been no published reports of respiratory disease occurring amongst workers in the hard metal (tungsten carbide) industry. In this paper the clinical and radiological findings in six cases and the pathological findings in one are described. In two cases physiological studies indicated mild alveolar diffusion defects. Histological examination in a fatal case revealed diffuse pulmonary interstitial fibrosis with marked peribronchial and perivascular fibrosis and bronchial epithelial hyperplasia and metaplasia. Radiological surveys revealed the sporadic occurrence and low incidence of the disease. The alterations in respiratory mechanics which occurred in two workers following a day's exposure to dust are described. Airborne dust concentrations are given. The industrial process is outlined and the literature is reviewed. The toxicity of the metals is discussed, and our findings are compared with those reported from Europe and the United States. We are of the opinion that the changes which we would describe as hard metal disease are caused by the inhalation of dust at work and that the component responsible may be cobalt. Images PMID:13970036

  17. Nanofluidic Size-Exclusion Chromatograph

    NASA Technical Reports Server (NTRS)

    Feldman, Sabrina; Svehla, Danielle; Grunthaner, Frank; Feldman, Jason; Shakkottai, P.

    2004-01-01

    Efforts are under way to develop a nanofluidic size-exclusion chromatograph (SEC), which would be a compact, robust, lightweight instrument for separating molecules of interest according to their sizes and measuring their relative abundances in small samples. About as large as a deck of playing cards, the nanofluidic SEC would serve, in effect, as a laboratory on a chip that would perform the functions of a much larger, conventional, bench-top SEC and ancillary equipment, while consuming much less power and much smaller quantities of reagent and sample materials. Its compactness and low power demand would render it attractive for field applications in which, typically, it would be used to identify and quantitate a broad range of polar and nonpolar organic compounds in soil, ice, and water samples. Size-exclusion chromatography is a special case of high-performance liquid chromatography. In a conventional SEC, a sample plug is driven by pressure along a column packed with silica or polymer beads that contain uniform nanopores. The interstices between, and the pores in, the beads collectively constitute a size-exclusion network. Molecules follow different paths through the size-exclusion network, such that characteristic elution times can be related to sizes of molecules: basically, smaller molecules reach the downstream end of the column after the larger ones do because the smaller ones enter minor pores and stay there for a while, whereas the larger ones do not enter the pores. The volume accessible to molecules gradually diminishes as their size increases. All molecules bigger than a pore size elute together. For most substances, the elution times and sizes of molecules can be correlated directly with molecular weights. Hence, by measuring the flux of molecules arriving at the downstream end as a function of time, one can obtain a liquid mass spectrum for the molecules present in a sample over a broad range of molecular weights.

  18. Measurement of the cross section ratio σψ(2S)/σJ/ψ(1S) in deep inelastic exclusive ep scattering at HERA

    NASA Astrophysics Data System (ADS)

    Ciborowsk, Jacek

    2016-11-01

    The exclusive deep inelastic electroproduction of ψ (2S) and J/ψ (1S) at an ep centre-of-mass energy of 317 GeV has been studied with the ZEUS detector at HERA in the kinematic range 2 < Q2 < 80 GeV2, 30 < W < 210 GeV and |t| < 1 GeV2, where Q2 is the photon virtuality, W is the photon-proton centre-of-mass energy and t is the squared four-momentum transfer at the proton vertex. The data for 2 < Q2 < 5 GeV2 were taken in the HERAI running period and correspond to an integrated luminosity of 114 pb-1. The data for 5 < Q2 < 80 GeV2 are from both HERAI and HERAII periods and correspond to an integrated luminosity of 468 pb-1. The decay modes analysed were μ+ μ- and J/ψ (1S) π+ π- for the ψ (2S) and μ+ μ- for the J/ψ(1S). The cross-section ratio σψ(2S)/σJ/ψ(1S) has been measured as a function of Q2; W and t. The results are compared to predictions of QCD-inspired models of exclusive vector-meson production.

  19. Measurement of the cross-section ratio σψ(2S)/σJ/ψ(1S) in deep inelastic exclusive ep scattering at HERA

    NASA Astrophysics Data System (ADS)

    Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Antonelli, S.; Aushev, V.; Aushev, Y.; Behnke, O.; Behrens, U.; Bertolin, A.; Bloch, I.; Boos, E. G.; Borras, K.; Brock, I.; Brook, N. H.; Brugnera, R.; Bruni, A.; Bussey, P. J.; Caldwell, A.; Capua, M.; Catterall, C. D.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cooper-Sarkar, A. M.; Corradi, M.; Corriveau, F.; Dementiev, R. K.; Devenish, R. C. E.; Dolinska, G.; Dusini, S.; Figiel, J.; Foster, B.; Gach, G.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gizhko, A.; Gladilin, L. K.; Golubkov, Yu. A.; Grebenyuk, J.; Gregor, I.; Grzelak, G.; Gueta, O.; Guzik, M.; Hain, W.; Hochman, D.; Hori, R.; Ibrahim, Z. A.; Iga, Y.; Ishitsuka, M.; Iudin, A.; Januschek, F.; Jomhari, N. Z.; Kadenko, I.; Kananov, S.; Karshon, U.; Kaur, M.; Kaur, P.; Kisielewska, D.; Klanner, R.; Klein, U.; Kondrashova, N.; Kononenko, O.; Korol, Ie.; Korzhavina, I. A.; Kotański, A.; Kötz, U.; Kovalchuk, N.; Kowalski, H.; Krupa, B.; Kuprash, O.; Kuze, M.; Levchenko, B. B.; Levy, A.; Libov, V.; Limentani, S.; Lisovyi, M.; Lobodzinska, E.; Löhr, B.; Lohrmann, E.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; Makarenko, I.; Malka, J.; Mergelmeyer, S.; Mohamad Idris, F.; Mohammad Nasir, N.; Myronenko, V.; Nagano, K.; Nobe, T.; Notz, D.; Nowak, R. J.; Onishchuk, Yu.; Paul, E.; Perlański, W.; Pokrovskiy, N. S.; Przybycień, M.; Roloff, P.; Rubinsky, I.; Ruspa, M.; Saxon, D. H.; Schioppa, M.; Schmidke, W. B.; Schneekloth, U.; Schörner-Sadenius, T.; Shcheglova, L. M.; Shevchenko, R.; Shkola, O.; Shyrma, Yu.; Singh, I.; Skillicorn, I. O.; Słomiński, W.; Solano, A.; Stanco, L.; Stefaniuk, N.; Stern, A.; Stopa, P.; Sztuk-Dambietz, J.; Szuba, D.; Szuba, J.; Tassi, E.; Tokushuku, K.; Tomaszewska, J.; Trofymov, A.; Tsurugai, T.; Turcato, M.; Turkot, O.; Tymieniecka, T.; Verbytskyi, A.; Viazlo, O.; Walczak, R.; Wan Abdullah, W. A. T.; Wichmann, K.; Wing, M.; Wolf, G.; Yamada, S.; Yamazaki, Y.; Zakharchuk, N.; Żarnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zhautykov, B. O.; Zhmak, N.; Zotkin, D. S.

    2016-08-01

    The exclusive deep inelastic electroproduction of ψ (2 S) and J / ψ (1 S) at an ep centre-of-mass energy of 317 GeV has been studied with the ZEUS detector at HERA in the kinematic range 2 exclusive vector-meson production.

  20. 77 FR 2278 - Notice of Availability for Exclusive, Non-Exclusive, or Partially-Exclusive Licensing of an...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF DEFENSE Department of the Army Notice of Availability for Exclusive, Non-Exclusive, or Partially-Exclusive Licensing of an Invention Concerning a Method and Device for Detection of Bioavailable Drug Concentration in...

  1. A perturbative approach to central exclusive production

    NASA Astrophysics Data System (ADS)

    Harland-Lang, L. A.; Khoze, V. A.; Ryskin, M. G.

    2015-02-01

    We review some selected results within the Durham model of central exclusive production. We present a detailed discussion of this theoretical approach for modeling exclusive processes and we briefly review some of its phenomenological applications.

  2. 40 CFR 1508.4 - Categorical exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 32 2010-07-01 2010-07-01 false Categorical exclusion. 1508.4 Section 1508.4 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX § 1508.4 Categorical exclusion. Categorical exclusion means a category of actions which do not individually...

  3. Approximating spatially exclusive invasion processes

    NASA Astrophysics Data System (ADS)

    Ross, Joshua V.; Binder, Benjamin J.

    2014-05-01

    A number of biological processes, such as invasive plant species and cell migration, are composed of two key mechanisms: motility and reproduction. Due to the spatially exclusive interacting behavior of these processes a cellular automata (CA) model is specified to simulate a one-dimensional invasion process. Three (independence, Poisson, and 2D-Markov chain) approximations are considered that attempt to capture the average behavior of the CA. We show that our 2D-Markov chain approximation accurately predicts the state of the CA for a wide range of motility and reproduction rates.

  4. Exclusive Dijet production from CDF2LHC

    SciTech Connect

    Gallinaro, Michele; /Rockefeller U.

    2005-04-01

    Exclusive dijet production at the Tevatron can be used as a benchmark to establish predictions on exclusive diffractive Higgs production, a process with a much smaller cross section. Exclusive dijet production in Double Pomeron Exchange processes, including diffractive Higgs production with measurements at the Tevatron and predictions for the Large Hadron Collider are presented. Using new data from the Tevatron and dedicated diffractive triggers, no excess over a smooth falling distribution for exclusive dijet events could be found. Upper limits on the exclusive dijet production cross section are presented and compared to current theoretical predictions.

  5. Beam-helicity asymmetry in photon and pion electroproduction in the Δ(1232)-resonance region at Q2 = 0.35(GeV/c)2

    NASA Astrophysics Data System (ADS)

    Bensafa, I. K.; Achenbach, P.; Ases Antelo, M.; Ayerbe, C.; Baumann, D.; Böhm, R.; Bosnar, D.; Burtin, E.; Defaÿ, X.; D'Hose, N.; Ding, M.; Distler, M. O.; Doria, L.; Fonvieille, H.; Friedrich, J. M.; Friedrich, J.; García Llongo, J.; Janssens, P.; Jover Mañas, G.; Kohl, M.; Laveissière, G.; Lloyd, M.; Makek, M.; Marroncle, J.; Merkel, H.; Merle, P.; Müller, U.; Nungesser, L.; Pasquini, B.; Pérez Benito, R.; Pochodzalla, J.; Potokar, M.; Rosner, G.; Sánchez Majos, S.; Seimetz, M.; Širca, S.; Spitzenberg, T.; Tamas, G.; van de Vyver, R.; van Hoorebeke, L.; Walcher, Th.; Weis, M.

    2007-04-01

    The beam-helicity asymmetry has been measured simultaneously for the reactions stackrel{{rightarrow}}{{e}} p→ epγ and stackrel{{rightarrow}}{{e}} p→ epπ 0 in the Δ(1232)-resonance region at Q 2 = 0.35( GeV/ c)2. The experiment was performed at MAMI with a longitudinally polarized beam and an out-of-plane detection of the proton. The results are compared with calculations based on dispersion relations for virtual Compton scattering and with the MAID model for pion electroproduction. There is an overall good agreement between experiment and theoretical calculations. The remaining discrepancies may be ascribed to an imperfect parametrization of some γ (*) N→ πN multipoles, mainly contributing to the non-resonant background. The beam-helicity asymmetry in both channels ( γ and π 0) shows a good sensitivity to these multipoles and should allow future improvement in their parametrization.

  6. Choreography of Ig allelic exclusion.

    PubMed

    Cedar, Howard; Bergman, Yehudit

    2008-06-01

    Allelic exclusion guarantees that each B or T cell only produces a single antigen receptor, and in this way contributes to immune diversity. This process is actually initiated in the early embryo when the immune receptor loci become asynchronously replicating in a stochastic manner with one early and one late allele in each cell. This distinct differential replication timing feature then serves an instructive mark that directs a series of allele-specific epigenetic events in the immune system, including programmed histone modification, nuclear localization and DNA demethylation that ultimately bring about preferred rearrangement on a single allele, and this decision is temporally stabilized by feedback mechanisms that inhibit recombination on the second allele. In principle, these same molecular components are also used for controlling monoallelic expression at other genomic loci, such as those carrying interleukins and olfactory receptor genes that require the choice of one gene out of a large array. Thus, allelic exclusion appears to represent a general epigenetic phenomenon that is modeled on the same basis as X chromosome inactivation.

  7. Incorporating cultural beliefs in promoting exclusive breastfeeding

    PubMed Central

    Reinsma, Kathryn; Bolima, Nancy; Fonteh, Florence; Okwen, Patrick; Yota, Daniel; Montgomery, Susanne

    2015-01-01

    Introduction Since 2003, the World Health Organization has recommended exclusive breastfeeding for the first 6 months of life. In the Northwest region of Cameroon approximately 90% of women initiate breastfeeding, yet only 34% of these women exclusively breastfeed for the recommended six months. Aim To determine influences on women’s exclusive breastfeeding practices. Methods Semi-structured interviews were conducted with six women and six men followed by focus group discussions with three groups of women and three groups of men in the Kumbo West Health District, Northwest region, Cameroon. All participants were selected using theoretical sampling to assure triangulation. Results Three themes emerged that influence exclusive breastfeeding practices: woman’s readiness to exclusively breastfeed; cultural influences towards exclusive breastfeeding; and perceived constraints to exclusive breastfeeding. Conclusion These emergent themes were used to create a theoretical framework that is useful for developing a breastfeeding health education intervention in non-Western settings. PMID:26973717

  8. Overview: Hard Rock Penetration

    SciTech Connect

    Dunn, J.C.

    1992-08-01

    The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

  9. Overview - Hard Rock Penetration

    SciTech Connect

    Dunn, James C.

    1992-03-24

    The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling Organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

  10. Overview: Hard Rock Penetration

    SciTech Connect

    Dunn, J.C.

    1992-01-01

    The Hard Rock Penetration program is developing technology to reduce the costs of drilling and completing geothermal wells. Current projects include: lost circulation control, rock penetration mechanics, instrumentation, and industry/DOE cost shared projects of the Geothermal Drilling organization. Last year, a number of accomplishments were achieved in each of these areas. A new flow meter being developed to accurately measure drilling fluid outflow was tested extensively during Long Valley drilling. Results show that this meter is rugged, reliable, and can provide useful measurements of small differences in fluid inflow and outflow rates. By providing early indications of fluid gain or loss, improved control of blow-out and lost circulation problems during geothermal drilling can be expected. In the area of downhole tools for lost circulation control, the concept of a downhole injector for injecting a two-component, fast-setting cementitious mud was developed. DOE filed a patent application for this concept during FY 91. The design criteria for a high-temperature potassium, uranium, thorium logging tool featuring a downhole data storage computer were established, and a request for proposals was submitted to tool development companies. The fundamental theory of acoustic telemetry in drill strings was significantly advanced through field experimentation and analysis. A new understanding of energy loss mechanisms was developed.

  11. Measuring the Hardness of Minerals

    ERIC Educational Resources Information Center

    Bushby, Jessica

    2005-01-01

    The author discusses Moh's hardness scale, a comparative scale for minerals, whereby the softest mineral (talc) is placed at 1 and the hardest mineral (diamond) is placed at 10, with all other minerals ordered in between, according to their hardness. Development history of the scale is outlined, as well as a description of how the scale is used…

  12. The AdS/QCD Correspondence and Exclusive Processes

    SciTech Connect

    Brodsky, Stanley J.; de Teramond, Guy F.; Deur, Alexandre; /Jefferson Lab

    2010-08-25

    The AdS/CFT correspondence between theories in AdS space and conformal field theories in physical space-time provides an analytic, semi-classical, color-confining model for strongly-coupled QCD. The soft-wall AdS/QCD model modified by a positive-sign dilaton metric leads to a remarkable one-parameter description of nonperturbative hadron dynamics at zero quark mass, including a zero-mass pion and a Regge spectrum of linear trajectories with the same slope in orbital angular momentum L and radial quantum number n for both mesons and baryons. One also predicts the form of the non-perturbative effective coupling {alpha}{sub s}{sup AdS}(q) and its {beta}-function which agrees with the effective coupling {alpha}{sub ga} extracted from the Bjorken sum rule. Light-front holography, which connects the fifth-dimensional coordinate of AdS space z to an invariant impact separation variable {zeta}, allows one to compute the analytic form of the frame-independent light-front wavefunctions, the fundamental entities which encode hadron properties as well as decay constants, form factors, deeply virtual Compton scattering, exclusive heavy hadron decays and other exclusive scattering amplitudes. One thus obtains a relativistic description of hadrons in QCD at the amplitude level with dimensional counting for hard exclusive reactions at high momentum transfer. As specific examples we discuss the behavior of the pion and nucleon form factors in the space-like and time-like regions. We also review the phenomenology of exclusive processes including some anomalous empirical results.

  13. Central exclusive production at RHIC

    SciTech Connect

    Adamczyk, Leszek; Guryn, Włodek; Turnau, Jacek

    2014-11-10

    The present status and future plans of the physics program of Central Exclusive Production (CEP) at RHIC are described. The measurements are based on the detection of the forward protons from the Double Pomeron Exchange (DPE) process in the Roman Pot system and of the recoil system of charged particles from the DPE process measured in the STAR experiment’s Time Projection Chamber (TPC). The data described here were taken using polarized proton-proton collisions at ps = 200 GeV. The preliminary spectra of two pion and four pion invariant mass reconstructed by STAR TPC in central region of pseudo-rapidity | | < 1, are presented. Near future plans to take data with the current system at center-of-mass energy ps = 200 GeV and plans to upgrade the forward proton tagging sys- tem are presented. Also a possible addition of the Roman Pots to the sPHENIX detector is discussed.

  14. Effects of calcium and magnesium hardness on the fertilization and hatching success of hybrid catfish eggs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hybrid catfish are exclusively produced by strip spawning of channel catfish females, fertilizing stripped eggs with blue catfish sperm, and hatching the fertilized eggs. As egg development takes outside the fish’s body, water hardness is one abioitic parameter, suggested to have a major effect on ...

  15. Beta Backscatter Measures the Hardness of Rubber

    NASA Technical Reports Server (NTRS)

    Morrissey, E. T.; Roje, F. N.

    1986-01-01

    Nondestructive testing method determines hardness, on Shore scale, of room-temperature-vulcanizing silicone rubber. Measures backscattered beta particles; backscattered radiation count directly proportional to Shore hardness. Test set calibrated with specimen, Shore hardness known from mechanical durometer test. Specimen of unknown hardness tested, and radiation count recorded. Count compared with known sample to find Shore hardness of unknown.

  16. Thin coatings and films hardness evaluation

    NASA Astrophysics Data System (ADS)

    Matyunin, V. M.; Marchenkov, A. Yu; Demidov, A. N.; Karimbekov, M. A.

    2016-10-01

    The existing thin coatings and films hardness evaluation methods based on indentation with pyramidal indenter on various scale levels are expounded. The impact of scale factor on hardness values is performed. The experimental verification of several existing hardness evaluation methods regarding the substrate hardness value and the “coating - substrate” composite hardness value is made.

  17. Nano-fabricated size exclusion chromatograph

    NASA Technical Reports Server (NTRS)

    Svehla, D.; Feldman, S.; Feldman, J.; Grunthaner, F.; Shakkottai, P.; Castillo, L. del; White, V.

    2002-01-01

    This paper describes the development of a nano-fabricated size exclusion chromatograph (nSEC) based on the principle that molecules traveling through amicrocolumn containing nano-fabricated features will have characteristic elution times that directly correlate to molecular weight. Compared to conventional size exclusion chromatography, the nSEC offers greater control over the size exclusion process; mass fabrication; integration of the separation column with associated valves, pumps, and detectors; and dramatic reductions in instrument mass and power requirements.

  18. Nanoindentation hardness of mineralized tissues.

    PubMed

    Oyen, Michelle L

    2006-01-01

    A series elastic and plastic deformation model [Sakai, M., 1999. The Meyer hardness: a measure for plasticity? Journal of Materials Research 14(9), 3630-3639] is used to deconvolute the resistance to plastic deformation from the plane strain modulus and contact hardness parameters obtained in a nanoindentation test. Different functional dependencies of contact hardness on the plane strain modulus are examined. Plastic deformation resistance values are computed from the modulus and contact hardness for engineering materials and mineralized tissues. Elastic modulus and plastic deformation resistance parameters are used to calculate elastic and plastic deformation components, and to examine the partitioning of indentation deformation between elastic and plastic. Both the numerical values of plastic deformation resistance and the direct computation of deformation partitioning reveal the intermediate mechanical responses of mineralized composites when compared with homogeneous engineering materials.

  19. Generalized parton distributions and rapidity gap survival in exclusive diffractive pp scattering

    SciTech Connect

    Frankfurt, L.; Hyde, C. E.; Strikman, M.; Weiss, C.

    2007-03-01

    We study rapidity gap survival (RGS) in the production of high-mass systems (H=dijet, heavy quarkonium, Higgs boson) in double-gap exclusive diffractive pp scattering, pp{yields}p+(gap)+H+(gap)+p. Our approach is based on the idea that hard and soft interactions are approximately independent because they proceed over widely different time and distance scales. We implement this idea in a partonic description of proton structure, which allows for a model-independent treatment of the interplay of hard and soft interactions. The high-mass system is produced in a hard scattering process with exchange of two gluons between the protons, whose amplitude is calculable in terms of the gluon generalized parton distribution (GPD), measured in exclusive ep scattering. The hard scattering process is modified by soft spectator interactions, which we calculate neglecting correlations between hard and soft interactions (independent interaction approximation). We obtain an analytic expression for the RGS probability in terms of the phenomenological pp elastic scattering amplitude, without reference to the eikonal approximation. Contributions from inelastic intermediate states are suppressed. The onset of the black-disk limit in pp scattering at TeV energies strongly suppresses diffraction at small impact parameters and is the main factor in determining the RGS probability. Correlations between hard and soft interactions (e.g. due to scattering from the long-range pion field of the proton or due to possible short-range transverse correlations between partons) further decrease the RGS probability. We also investigate the dependence of the diffractive cross section on the transverse momenta of the final-state protons ('diffraction pattern'). By measuring this dependence one can perform detailed tests of the interplay of hard and soft interactions and even extract information about the gluon GPD in the proton. Such studies appear to be feasible with the planned forward detectors at the

  20. Central exclusive production at RHIC

    DOE PAGES

    Adamczyk, Leszek; Guryn, Włodek; Turnau, Jacek

    2014-11-10

    The present status and future plans of the physics program of Central Exclusive Production (CEP) at RHIC are described. The measurements are based on the detection of the forward protons from the Double Pomeron Exchange (DPE) process in the Roman Pot system and of the recoil system of charged particles from the DPE process measured in the STAR experiment’s Time Projection Chamber (TPC). The data described here were taken using polarized proton-proton collisions at ps = 200 GeV. The preliminary spectra of two pion and four pion invariant mass reconstructed by STAR TPC in central region of pseudo-rapidity | |more » < 1, are presented. Near future plans to take data with the current system at center-of-mass energy ps = 200 GeV and plans to upgrade the forward proton tagging sys- tem are presented. Also a possible addition of the Roman Pots to the sPHENIX detector is discussed.« less

  1. A multispecies exclusion model inspired by transcriptional interference

    NASA Astrophysics Data System (ADS)

    Ghosh, Soumendu; Bameta, Tripti; Ghanti, Dipanwita; Chowdhury, Debashish

    2016-12-01

    We introduce exclusion models of two distinguishable species of hard rods with their distinct sites of entry and exit under open boundary conditions. In the first model both species of rods move in the same direction whereas in the other two models they move in the opposite direction. These models are motivated by the biological phenomenon known as transcriptional interference. Therefore, the rules for the kinetics of the models, particularly the rules for the outcome of the encounter of the rods, are also formulated to mimic those observed in transcriptional interference. By a combination of mean-field theory and computer simulation of these models we demonstrate how the flux of one species of rods is completely switched off by the other. Exploring the parameter space of the model we also establish the conditions under which switch-like regulation of two fluxes is possible; from the extensive analysis we discover more than one possible mechanism of this phenomenon.

  2. CMS results on exclusive and diffractive production

    SciTech Connect

    Alves, Gilvan A.

    2015-04-10

    We present recent CMS measurements of diffractive and exclusive processes, using data collected at 7 TeV at the LHC. Measurements of soft single- and double-diffractive cross sections are presented, as well as measurements of photon-induced processes including studies of exclusive WW production via photon-photon exchange.

  3. 10 CFR 830.2 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Exclusions. 830.2 Section 830.2 Energy DEPARTMENT OF ENERGY NUCLEAR SAFETY MANAGEMENT § 830.2 Exclusions. This part does not apply to: (a) Activities that are... 1974, as amended; and (e) Activities related to the launch approval and actual launch of nuclear...

  4. 47 CFR 76.107 - Exclusivity contracts.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Exclusivity contracts. 76.107 Section 76.107 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports...

  5. 47 CFR 1.6005 - Exclusive defenses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 1 2010-10-01 2010-10-01 false Exclusive defenses. 1.6005 Section 1.6005... Against Satellite Carriers for Retransmission Without Consent § 1.6005 Exclusive defenses. (a) The defenses listed in paragraphs (a)(1) through (a)(4) of this section, are the only defenses available to...

  6. 47 CFR 1.6005 - Exclusive defenses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 1 2011-10-01 2011-10-01 false Exclusive defenses. 1.6005 Section 1.6005... Against Satellite Carriers for Retransmission Without Consent § 1.6005 Exclusive defenses. (a) The defenses listed in paragraphs (a)(1) through (a)(4) of this section, are the only defenses available to...

  7. 32 CFR 536.46 - Other exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Other exclusions. 536.46 Section 536.46 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY CLAIMS AND ACCOUNTS CLAIMS AGAINST THE UNITED STATES Investigation and Processing of Claims § 536.46 Other exclusions. (a) Statutory employer....

  8. 10 CFR 830.2 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 4 2012-01-01 2012-01-01 false Exclusions. 830.2 Section 830.2 Energy DEPARTMENT OF ENERGY NUCLEAR SAFETY MANAGEMENT § 830.2 Exclusions. This part does not apply to: (a) Activities that are... 1974, as amended; and (e) Activities related to the launch approval and actual launch of nuclear...

  9. 10 CFR 830.2 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 4 2013-01-01 2013-01-01 false Exclusions. 830.2 Section 830.2 Energy DEPARTMENT OF ENERGY NUCLEAR SAFETY MANAGEMENT § 830.2 Exclusions. This part does not apply to: (a) Activities that are... 1974, as amended; and (e) Activities related to the launch approval and actual launch of nuclear...

  10. 10 CFR 830.2 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 4 2011-01-01 2011-01-01 false Exclusions. 830.2 Section 830.2 Energy DEPARTMENT OF ENERGY NUCLEAR SAFETY MANAGEMENT § 830.2 Exclusions. This part does not apply to: (a) Activities that are... 1974, as amended; and (e) Activities related to the launch approval and actual launch of nuclear...

  11. 10 CFR 830.2 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 4 2014-01-01 2014-01-01 false Exclusions. 830.2 Section 830.2 Energy DEPARTMENT OF ENERGY NUCLEAR SAFETY MANAGEMENT § 830.2 Exclusions. This part does not apply to: (a) Activities that are... 1974, as amended; and (e) Activities related to the launch approval and actual launch of nuclear...

  12. 47 CFR 73.232 - Territorial exclusivity.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 4 2010-10-01 2010-10-01 false Territorial exclusivity. 73.232 Section 73.232 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES FM Broadcast Stations § 73.232 Territorial exclusivity. No licensee of an FM broadcast station shall have...

  13. 47 CFR 73.232 - Territorial exclusivity.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Territorial exclusivity. 73.232 Section 73.232 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES RADIO BROADCAST SERVICES FM Broadcast Stations § 73.232 Territorial exclusivity. No licensee of an FM broadcast station shall have...

  14. 47 CFR 76.107 - Exclusivity contracts.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 4 2011-10-01 2011-10-01 false Exclusivity contracts. 76.107 Section 76.107 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports...

  15. 48 CFR 19.1504 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 1 2011-10-01 2011-10-01 false Exclusions. 19.1504 Section 19.1504 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS Women-Owned Small Business (WOSB) Program 19.1504 Exclusions. This...

  16. 12 CFR 229.42 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Exclusions. 229.42 Section 229.42 Banks and Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM AVAILABILITY OF FUNDS AND COLLECTION OF CHECKS (REGULATION CC) Collection of Checks § 229.42 Exclusions....

  17. 47 CFR 76.107 - Exclusivity contracts.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Exclusivity contracts. 76.107 Section 76.107 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports...

  18. 47 CFR 76.107 - Exclusivity contracts.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 4 2012-10-01 2012-10-01 false Exclusivity contracts. 76.107 Section 76.107 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) BROADCAST RADIO SERVICES MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports...

  19. Exclusion from School and Recognition of Difference

    ERIC Educational Resources Information Center

    McCluskey, Gillean; Riddell, Sheila; Weedon, Elisabet; Fordyce, Mariela

    2016-01-01

    There has been an overall decrease in exclusion rates and numbers in recent years across the UK. This change has often been heralded as evidence that national inclusion policies are "working" and that schools themselves are becoming increasingly inclusive. This article examines findings from a recent study on school exclusion in Wales,…

  20. 24 CFR 58.35 - Categorical exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Environmental Review Process: Documentation, Range of Activities, Project Aggregation and Classification § 58.35 Categorical exclusions. Categorical exclusion refers to a category of activities for which no environmental... needed with respect to environmental requirements, except where paragraph (c) of this section...

  1. 12 CFR 367.5 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... EXCLUSION OF CONTRACTOR AND TERMINATION OF CONTRACTS § 367.5 Exclusions. (a) The Ethics Counselor may... also prohibited from conducting business with FDIC as agents or representatives of other contractors... Ethics Counselor's decision to exclude the contractor pursuant to § 367.16. Provided further, that...

  2. Exclusion and Education in South Africa: An Education Law Perspective of Emerging Alternative Understandings of Exclusion

    ERIC Educational Resources Information Center

    Beckmann, Johan

    2016-01-01

    The new democratic dispensation in South Africa (1994) was accompanied by law and policy aimed at preventing unfair exclusion from educational opportunities and promoting equal access to educational opportunities. However, feelings of unfair exclusion remain and new understandings of exclusion are emerging. This paper examines the new policy and…

  3. Monodisperse hard rods in external potentials.

    PubMed

    Bakhti, Benaoumeur; Karbach, Michael; Maass, Philipp; Müller, Gerhard

    2015-10-01

    We consider linear arrays of cells of volume V(c) populated by monodisperse rods of size σV(c),σ=1,2,..., subject to hardcore exclusion interaction. Each rod experiences a position-dependent external potential. In one application we also examine effects of contact forces between rods. We employ two distinct methods of exact analysis with complementary strengths and different limits of spatial resolution to calculate profiles of pressure and density on mesoscopic and microscopic length scales at thermal equilibrium. One method uses density functionals and the other statistically interacting vacancy particles. The applications worked out include gravity, power-law traps, and hard walls. We identify oscillations in the profiles on a microscopic length scale and show how they are systematically averaged out on a well-defined mesoscopic length scale to establish full consistency between the two approaches. The continuum limit, realized as V(c)→0,σ→∞ at nonzero and finite σV(c), connects our highest-resolution results with known exact results for monodisperse rods in a continuum. We also compare the pressure profiles obtained from density functionals with the average microscopic pressure profiles derived from the pair distribution function.

  4. Factors associated with latent fingerprint exclusion determinations.

    PubMed

    Ulery, Bradford T; Hicklin, R Austin; Roberts, Maria Antonia; Buscaglia, JoAnn

    2017-02-22

    Exclusion is the determination by a latent print examiner that two friction ridge impressions did not originate from the same source. The concept and terminology of exclusion vary among agencies. Much of the literature on latent print examination focuses on individualization, and much less attention has been paid to exclusion. This experimental study assesses the associations between a variety of factors and exclusion determinations. Although erroneous exclusions are more likely to occur on some images and for some examiners, they were widely distributed among images and examiners. Measurable factors found to be associated with exclusion rates include the quality of the latent, value determinations, analysis minutia count, comparison difficulty, and the presence of cores or deltas. An understanding of these associations will help explain the circumstances under which errors are more likely to occur and when determinations are less likely to be reproduced by other examiners; the results should also lead to improved effectiveness and efficiency of training and casework quality assurance. This research is intended to assist examiners in improving the examination process and provide information to the broader community regarding the accuracy, reliability, and implications of exclusion decisions.

  5. Future hard disk drive systems

    NASA Astrophysics Data System (ADS)

    Wood, Roger

    2009-03-01

    This paper briefly reviews the evolution of today's hard disk drive with the additional intention of orienting the reader to the overall mechanical and electrical architecture. The modern hard disk drive is a miracle of storage capacity and function together with remarkable economy of design. This paper presents a personal view of future customer requirements and the anticipated design evolution of the components. There are critical decisions and great challenges ahead for the key technologies of heads, media, head-disk interface, mechanics, and electronics.

  6. Magnetic levitation for hard superconductors

    SciTech Connect

    Kordyuk, A.A.

    1998-01-01

    An approach for calculating the interaction between a hard superconductor and a permanent magnet in the field-cooled case is proposed. The exact solutions were obtained for the point magnetic dipole over a flat ideally hard superconductor. We have shown that such an approach is adaptable to a wide practical range of melt-textured high-temperature superconductors{close_quote} systems with magnetic levitation. In this case, the energy losses can be calculated from the alternating magnetic field distribution on the superconducting sample surface. {copyright} {ital 1998 American Institute of Physics.}

  7. Dynamic indentation hardness of materials

    NASA Astrophysics Data System (ADS)

    Koeppel, Brian James

    Indentation hardness is one of the simplest and most commonly used measures for quickly characterizing material response under static loads. Hardness may mean resistance to cutting to a machinist, resistance to wear to a tribologist, or a measure of flow stress to a design engineer. In this simple technique, a predetermined force is applied to an indenter for 5-30 seconds causing it to penetrate a specimen. By measuring the load and the indentation size, a hardness value is determined. However, the rate of deformation during indenter penetration is of the order of 10sp{-4}\\ ssp{-1}. In most practical applications, such as high speed machining or impact, material deforms at strain rates in excess of 10sp3{-}10sp5\\ ssp{-1}. At such high rates, it is well established that the plastic behavior of materials is considerably different from their static counterpart. For example, materials exhibit an increase in their yield stress, flow stress, fracture stress, and fracture toughness at high strain rates. Hence, the use of static hardness as an indicator of material response under dynamic loads may not be appropriate. Accordingly, a simple dynamic indentation hardness tester is developed for characterizing materials at strain rates similar to those encountered in realistic situations. The experimental technique uses elastic stress wave propagation phenomena in a slender rod. The technique is designed to deliver a single indentation load of 100-200 mus duration. Similar to static measurements, the dynamic hardness is determined from the measured load and indentation size. Hardness measurements on a range of metals have revealed that the dynamic hardness is consistently greater than the static hardness. The increase in hardness is strongly dependent on the crystal structure of the material. The observed trends in hardness are also found to be consistent with the yield and flow stresses of these materials under uniaxial compression. Therefore, it is suggested that the

  8. 42 CFR 1001.1901 - Scope and effect of exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Scope and effect of exclusion. 1001.1901 Section... SERVICES OIG AUTHORITIES PROGRAM INTEGRITY-MEDICARE AND STATE HEALTH CARE PROGRAMS Waivers and Effect of Exclusion § 1001.1901 Scope and effect of exclusion. (a) Scope of exclusion. Exclusions of individuals...

  9. Induced polarization of Λ(1116) in kaon electroproduction

    SciTech Connect

    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.; 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.; El Fassi, 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.; Sabatié, 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.; Zonta, I.

    2014-09-01

    We have measured the induced polarization of the Λ(1116) in the reaction ep→e'K+Λ, detecting the scattered e' and K+ in the final state along with the proton from the decay Λ→pπ-.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.

  10. Spectroscopy of LiΛ9 by electroproduction

    SciTech Connect

    Urciuoli, G. M.; Cusanno, F.; Marrone, S.; Acha, A.; Ambrozewicz, P.; Aniol, K. A.; Baturin, P.; Bertin, P. Y.; Benaoum, H.; Blomqvist, K. I.; Boeglin, W. U.; Breuer, H.; Brindza, P.; Bydžovský, P.; Camsonne, A.; Chang, C. C.; Chen, J.-P.; Choi, Seonho; Chudakov, E. A.; Cisbani, E.; Colilli, S.; Coman, L.; Craver, B. J.; De Cataldo, G.; de Jager, C. W.; De Leo, R.; Deur, A. P.; Ferdi, C.; Feuerbach, R. J.; Folts, E.; Fratoni, R.; Frullani, S.; Garibaldi, F.; Gayou, O.; Giuliani, F.; Gomez, J.; Gricia, M.; Hansen, J. O.; Hayes, D.; Higinbotham, D. W.; Holmstrom, T. K.; Hyde, C. E.; Ibrahim, H. F.; Iodice, M.; Jiang, X.; Kaufman, L. J.; Kino, K.; Kross, B.; Lagamba, L.; LeRose, J. J.; Lindgren, R. A.; Lucentini, M.; Margaziotis, D. J.; Markowitz, P.; Meziani, Z. E.; McCormick, K.; Michaels, R. W.; Millener, D. J.; Miyoshi, T.; Moffit, B.; Monaghan, P. A.; Moteabbed, M.; Camacho, C. Muñoz; Nanda, S.; Nappi, E.; Nelyubin, V. V.; Norum, B. E.; Okasyasu, Y.; Paschke, K. D.; Perdrisat, C. F.; Piasetzky, E.; Punjabi, V. A.; Qiang, Y.; Reimer, P. E.; Reinhold, J.; Reitz, B.; Roche, R. E.; Rodriguez, V. M.; Saha, A.; Santavenere, F.; Sarty, A. J.; Segal, J.; Shahinyan, A.; Singh, J.; Širca, S.; Snyder, R.; Solvignon, P. H.; Sotona, M.; Subedi, R.; Sulkosky, V. A.; Suzuki, T.; Ueno, H.; Ulmer, P. E.; Veneroni, P.; Voutier, E.; Wojtsekhowski, B. B.; Zheng, X.; Zorn, C.

    2015-03-01

    Background: In the absence of accurate data on the free two-body hyperon-nucleon interaction, the spectra of hypernuclei can provide information on the details of the effective hyperon-nucleon interaction. Purpose: To obtain a high-resolution spectrum for the 9Be(e,e'K+)9ΛLi reaction. Method: Electroproduction of the hypernucleus 9ΛLi has been studied for the first time with sub-MeV energy resolution in Hall A at Jefferson Lab on a 9Be target. In order to increase the counting rate and to provide unambiguous kaon identification, two superconducting septum magnets and a Ring Imaging CHerenkov detector (RICH) were added to the Hall A standard equipment. Results: The cross section to low-lying states of 9ΛLi is concentrated within 3 MeV of the ground state and can be fitted with four peaks. The positions of the doublets agree with theory while a disagreement could exist with respect to the relative strengths of the peaks in the doublets. A Λ separation energy, BΛ, of 8.36±0.08 (stat.) ±0.08 (syst.) MeV was measured, in agreement with an earlier experiment.

  11. Accessing proton generalized parton distributions and pion distribution amplitudes with the exclusive pion-induced Drell-Yan process at J-PARC

    NASA Astrophysics Data System (ADS)

    Sawada, Takahiro; Chang, Wen-Chen; Kumano, Shunzo; Peng, Jen-Chieh; Sawada, Shinya; Tanaka, Kazuhiro

    2016-06-01

    Generalized parton distributions (GPDs) encoding multidimensional information of hadron partonic structure appear as the building blocks in a factorized description of hard exclusive reactions. The nucleon GPDs have been accessed by deeply virtual Compton scattering and deeply virtual meson production with lepton beam. A complementary probe with hadron beam is the exclusive pion-induced Drell-Yan process. In this paper, we discuss recent theoretical advances on describing this process in terms of nucleon GPDs and pion distribution amplitudes. Furthermore, we address the feasibility of measuring the exclusive pion-induced Drell-Yan process π-p →μ+μ-n via a spectrometer at the High Momentum Beamline being constructed at J-PARC in Japan. Realization of such measurement at J-PARC will provide a new test of perturbative QCD descriptions of a novel class of hard exclusive reactions. It will also offer the possibility of experimentally accessing nucleon GPDs at large timelike virtuality.

  12. Central exclusive production and the Durham model

    NASA Astrophysics Data System (ADS)

    Harland-Lang, L. A.; Khoze, V. A.; Ryskin, M. G.

    2014-11-01

    We review some selected results within the Durham model of central exclusive production. We discuss the theoretical aspects of this approach and consider the phenomenological implications for a selection of processes.

  13. Teaching With Documents: Chinese Exclusion Forms.

    ERIC Educational Resources Information Center

    Simmons, Linda, Ed.

    1986-01-01

    Reviews the history of Chinese immigration to the United States and provides a facsimilie of a form used to document immigrants under the Chinese Exclusion Act. Teaching suggestions are included. (JDH)

  14. Exclusion of pneumothorax by radionuclide lung scan

    SciTech Connect

    Weiss, P.E.

    1986-05-01

    A case is reported in which ventilation lung imaging was useful in excluding a large pneumothorax. This technique may be helpful in patients with emphysema in whom exclusion of pneumothorax by radiographic criteria might be difficult.

  15. 48 CFR 37.202 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... CONTRACTING SERVICE CONTRACTING Advisory and Assistance Services 37.202 Exclusions. The following activities...) Routine information technology services unless they are an integral part of a contract for the acquisition... research involving medical, biological, physical, social, psychological, or other phenomena....

  16. 40 CFR 113.5 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... SMALL ONSHORE STORAGE FACILITIES Oil Storage Facilities § 113.5 Exclusions. This subpart does not apply to: (a) Those facilities whose average daily oil throughout is more than their fixed oil...

  17. 40 CFR 113.5 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... SMALL ONSHORE STORAGE FACILITIES Oil Storage Facilities § 113.5 Exclusions. This subpart does not apply to: (a) Those facilities whose average daily oil throughout is more than their fixed oil...

  18. 40 CFR 113.5 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... SMALL ONSHORE STORAGE FACILITIES Oil Storage Facilities § 113.5 Exclusions. This subpart does not apply to: (a) Those facilities whose average daily oil throughout is more than their fixed oil...

  19. 40 CFR 113.5 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... SMALL ONSHORE STORAGE FACILITIES Oil Storage Facilities § 113.5 Exclusions. This subpart does not apply to: (a) Those facilities whose average daily oil throughout is more than their fixed oil...

  20. 40 CFR 113.5 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... SMALL ONSHORE STORAGE FACILITIES Oil Storage Facilities § 113.5 Exclusions. This subpart does not apply to: (a) Those facilities whose average daily oil throughout is more than their fixed oil...

  1. 32 CFR 989.13 - Categorical exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.13 Categorical exclusion. (a) CATEXs define those categories... environment and do not, therefore, require further environmental analysis in an EA or an EIS. The list of...

  2. Metrics for Hard Goods Merchandising.

    ERIC Educational Resources Information Center

    Cooper, Gloria S., Ed.; Magisos, Joel H., Ed.

    Designed to meet the job-related metric measurement needs of students interested in hard goods merchandising, this instructional package is one of five for the marketing and distribution cluster, part of a set of 55 packages for metric instruction in different occupations. The package is intended for students who already know the occupational…

  3. Playing the Numbers: Hard Choices

    ERIC Educational Resources Information Center

    Doyle, William R.

    2009-01-01

    Stateline.org recently called this recession the worst in 50 years for state budgets. As has been the case in past economic downturns, higher education looks to be particularly hard hit. Funds from the American Recovery and Relief Act may have postponed some of the difficulty for many colleges and universities, but the outlook for public higher…

  4. Hard Trying and These Recipes

    ERIC Educational Resources Information Center

    Atwell, Nancie

    2003-01-01

    Writers thrive when they are motivated to work hard, have regular opportunities to practice and reflect, and benefit from a knowledgeable teacher who knows writing. Student feedback to lessons during writing workshop helped guide Nancie Atwell in her quest to provide the richest and most efficient path to better writing.

  5. FATIGUE OF BIOMATERIALS: HARD TISSUES

    PubMed Central

    Arola, D.; Bajaj, D.; Ivancik, J.; Majd, H.; Zhang, D.

    2009-01-01

    The fatigue and fracture behavior of hard tissues are topics of considerable interest today. This special group of organic materials comprises the highly mineralized and load-bearing tissues of the human body, and includes bone, cementum, dentin and enamel. An understanding of their fatigue behavior and the influence of loading conditions and physiological factors (e.g. aging and disease) on the mechanisms of degradation are essential for achieving lifelong health. But there is much more to this topic than the immediate medical issues. There are many challenges to characterizing the fatigue behavior of hard tissues, much of which is attributed to size constraints and the complexity of their microstructure. The relative importance of the constituents on the type and distribution of defects, rate of coalescence, and their contributions to the initiation and growth of cracks, are formidable topics that have not reached maturity. Hard tissues also provide a medium for learning and a source of inspiration in the design of new microstructures for engineering materials. This article briefly reviews fatigue of hard tissues with shared emphasis on current understanding, the challenges and the unanswered questions. PMID:20563239

  6. Exclusive Reactions Involving Pions and Nucleons

    NASA Technical Reports Server (NTRS)

    Norbury, John W.; Blattnig, Steve R.; Tripathi, R. K.

    2002-01-01

    The HZETRN code requires inclusive cross sections as input. One of the methods used to calculate these cross sections requires knowledge of all exclusive processes contributing to the inclusive reaction. Conservation laws are used to determine all possible exclusive reactions involving strong interactions between pions and nucleons. Inclusive particle masses are subsequently determined and are needed in cross-section calculations for inclusive pion production.

  7. Rescinding the Ground Combat Exclusion Policy

    DTIC Science & Technology

    2011-04-07

    memorandum, he then issued DoD’s current policy regarding the assignment of women : Rule. Service members are eligible to be assigned to all positioi). S ...Miller, " Feminism and the Exclusion of Army Women from Combat," in Women in the Military, ed. Rita James Simon (New Brunswick, NJ: Transaction...index.php/issuepapers (accessed November 23, 2010). Miller, Laura L. " Feminism and the Exclusion of Army Women from Combat." In Women in the Military

  8. Hard processes in hadronic interactions

    SciTech Connect

    Satz, H. |; Wang, X.N.

    1995-07-01

    Quantum chromodynamics is today accepted as the fundamental theory of strong interactions, even though most hadronic collisions lead to final states for which quantitative QCD predictions are still lacking. It therefore seems worthwhile to take stock of where we stand today and to what extent the presently available data on hard processes in hadronic collisions can be accounted for in terms of QCD. This is one reason for this work. The second reason - and in fact its original trigger - is the search for the quark-gluon plasma in high energy nuclear collisions. The hard processes to be considered here are the production of prompt photons, Drell-Yan dileptons, open charm, quarkonium states, and hard jets. For each of these, we discuss the present theoretical understanding, compare the resulting predictions to available data, and then show what behaviour it leads to at RHIC and LHC energies. All of these processes have the structure mentioned above: they contain a hard partonic interaction, calculable perturbatively, but also the non-perturbative parton distribution within a hadron. These parton distributions, however, can be studied theoretically in terms of counting rule arguments, and they can be checked independently by measurements of the parton structure functions in deep inelastic lepton-hadron scattering. The present volume is the work of Hard Probe Collaboration, a group of theorists who are interested in the problem and were willing to dedicate a considerable amount of their time and work on it. The necessary preparation, planning and coordination of the project were carried out in two workshops of two weeks` duration each, in February 1994 at CERn in Geneva andin July 1994 at LBL in Berkeley.

  9. 5 CFR 919.1020 - Voluntary exclusion or voluntarily excluded.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...) CIVIL SERVICE REGULATIONS (CONTINUED) GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 919.1020 Voluntary exclusion or voluntarily excluded. (a) Voluntary exclusion means a person's.... Voluntary exclusion must have governmentwide effect. (b) Voluntarily excluded means the status of a...

  10. Details on Exclusive Use Data Protection for Minor Use Registrations

    EPA Pesticide Factsheets

    This document provides information about issues related to exclusive use data protection for minor use registrations, including extension of the exclusive use period and establishing a new exclusive use period.

  11. 78 FR 27181 - Notice of Intent To Grant Exclusive Licenses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-09

    ..., an exclusive license to the blackberry variety named ``Columbia Star,'' an exclusive license to the... Agriculture. The ] prospective exclusive licenses will be royalty-bearing and will comply with the terms...

  12. Enthalpy versus Entropy: the Thermodynamic Origin of Hard Particle Ordering

    NASA Astrophysics Data System (ADS)

    Anthamatten, Mitchell; Chen, Shaw; Ou, Jane; Weinfeld, Jeffrey; Department of Chemical Engineering Team

    The topic of hard particle ordering transitions is important in the development of molecular to mesoscale materials with potential applications in biomedicine, catalysis, optoelectronics, and renewable energy. The first step toward deterministic materials design rests on understanding the thermodynamic nature of ordering transitions involving two phases in equilibrium. We apply classical thermodynamics to show that (i) first-order, hard particle ordering transitions are forbidden at constant volume; and that (ii) hard-particle ordering is driven by a loss in enthalpy through volume reduction that outweighs a concomitant entropy loss upon ordering. The traditional approach considers minimization of Helmholtz energy, at constant volume, whereas the current study exclusively focuses on equilibrium phase transitions and, therefore, targets minimization of Gibbs energy at constant pressure. The Gibbs energy platform offers physically intuitive interpretations consistent with existing computation and experiments. The prevalent idea of entropy-driven ordering at constant V is restricted to transitions from non-equilibrium initial states that have yet to be properly defined for quantification. Laboratory of Laser Energetics, DE-FC52-08NA28302.

  13. Probing young drinking water biofilms with hard and soft particles.

    PubMed

    Paris, Tony; Skali-Lami, Salaheddine; Block, Jean-Claude

    2009-01-01

    The aim of our study was to investigate, through the use of soft (Escherichia coli) and hard (polystyrene microspheres) particles, the distribution and persistence of allochthonous particles inoculated in drinking water flow chambers. Biofilms were allowed to grow for 7-10 months in tap water from Nancy's drinking water network and were composed of bacterial aggregates and filamentous fungi. Both model particles adhered almost exclusively on the biofilms (i.e. on the bacterial aggregates and on the filamentous structures) and not directly on the uncolonized walls (glass or Plexiglas). Biofilm age (i.e. bacterial density and biofilm properties) and convective-diffusion were found to govern particle accumulation: older biofilms and higher wall shear rates both increased the velocity and the amount of particle deposition on the biofilm. Persistence of the polystyrene particles was measured over a two-month period after inoculation. Accumulation amounts were found to be very different between hard and soft particles as only 0.03 per thousand of the soft particles inoculated accumulated in the biofilm against 0.3-0.8% for hard particles.

  14. Improved self-exclusion program: preliminary results.

    PubMed

    Tremblay, Nicole; Boutin, Claude; Ladouceur, Robert

    2008-12-01

    The gambling industry has offered self-exclusion programs for quite a long time. Such measures are designed to limit access to gaming opportunities and provide problem gamblers with the help they need to cease or limit their gambling behaviour. However, few studies have empirically evaluated these programs. This study has three objectives: (1) to observe the participation in an improved self-exclusion program that includes an initial voluntary evaluation, phone support, and a mandatory meeting, (2) to evaluate satisfaction and usefulness of this service as perceived by self-excluders, (3) to measure the preliminary impact of this improved program. One hundred sixteen self-excluders completed a questionnaire about their satisfaction and their perception of the usefulness during the mandatory meeting. Among those participants, 39 attended an initial meeting. Comparisons between data collected at the initial meeting and data taken at the final meeting were made for those 39 participants. Data showed that gamblers chose the improved self-exclusion program 75% of the time; 25% preferred to sign a regular self-exclusion contract. Among those who chose the improved service, 40% wanted an initial voluntary evaluation and 37% of these individuals actually attended that meeting. Seventy percent of gamblers came to the mandatory meeting, which was a required condition to end their self-exclusion. The majority of participants were satisfied with the improved self-exclusion service and perceived it as useful. Major improvements were observed between the final and the initial evaluation on time and money spent, consequences of gambling, DSM-IV score, and psychological distress. The applicability of an improved self-exclusion program is discussed and, as shown in our study, the inclusion of a final mandatory meeting might not be so repulsive for self-excluders. Future research directives are also proposed.

  15. Electroproduction of {eta} mesons in the S{sub 11}(1535) resonance region at high momentum transfer

    SciTech Connect

    Dalton, M. M.; Adams, G. S.; Moziak, B.; Stoler, P.; Villano, A.; Ahmidouch, A.; Danagoulian, S.; Angelescu, T.; Malace, S.; Arrington, J.; Hafidi, K.; Holt, R. J.; Reimer, P. E.; Schulte, E.; Zheng, X.; Asaturyan, R.; Mkrtchyan, H.; Navasardyan, T.; Tadevosyan, V.; Baker, O. K.

    2009-07-15

    The differential cross section for the process p(e,e{sup '}p){eta} has been measured at Q{sup 2}{approx}5.7 and 7.0(GeV/c){sup 2} for center-of-mass energies from threshold to 1.8 GeV, encompassing the S{sub 11}(1535) resonance, which dominates the channel. This is the highest momentum-transfer measurement of this exclusive process to date. The helicity-conserving transition amplitude A{sub 1/2}, for the production of the S{sub 11}(1535) resonance, is extracted from the data. Within the limited Q{sup 2} now measured, this quantity appears to begin scaling as Q{sup -3}--a predicted, but not definitive, signal of the dominance of perturbative QCD at Q{sup 2}{approx}5 (GeV/c){sup 2}.

  16. Electroproduction of {eta} mesons in the S{sub 11} (1535) resonance region at high momentum transfer.

    SciTech Connect

    Dalton, M. M.; Adams, G. S.; Ahmidouch, A.; Angelescu, T.; Arrington, J.; Holt, R. J.; Hafidi, K.; Reimer, P.; Schulte, E.; Zheng, X.; Physics; Univ. of Witwatersrand; Rensselaer Polytechnic Inst.; North Carolina A & T State Univ.; Bucharest Univ.; Yerevan Physics Inst.

    2009-07-01

    The differential cross section for the process p(e,e{prime}p) {eta} has been measured at Q{sup 2} {approx} 5.7 and 7.0(GeV/c){sup 2} for center-of-mass energies from threshold to 1.8 GeV, encompassing the S{sub 11}(1535) resonance, which dominates the channel. This is the highest momentum-transfer measurement of this exclusive process to date. The helicity-conserving transition amplitude A{sub 1/2}, for the production of the S{sub 11}(1535) resonance, is extracted from the data. Within the limited Q{sup 2} now measured, this quantity appears to begin scaling as Q{sup -3} - a predicted, but not definitive, signal of the dominance of perturbative QCD at Q{sup 2} {approx} 5 (GeV/c){sup 2}.

  17. Transpecific microsatellites for hard pines.

    PubMed

    Shepherd, M.; Cross, M.; Maguire, L.; Dieters, J.; Williams, G.; Henry, J.

    2002-04-01

    Microsatellites are difficult to recover from large plant genomes so cross-specific utilisation is an important source of markers. Fifty microsatellites were tested for cross-specific amplification and polymorphism to two New World hard pine species, slash pine ( Pinus elliottii var. elliottii) and Caribbean pine ( P. caribaea var. hondurensis). Twenty-nine (58%) markers amplified in both hard pine species, and 23 of these 29 were polymorphic. Soft pine (subgenus Strobus) microsatellite markers did amplify, but none were polymorphic. Pinus elliottii var. elliottii and P. caribaea var. hondurensis showed mutational changes in the flanking regions and the repeat motif that were informative for Pinus spp. phylogenetic relationships. Most allele length variation could be attributed to variability in repeat unit number. There was no evidence for ascertainment bias.

  18. Ultrasonic material hardness depth measurement

    DOEpatents

    Good, Morris S.; Schuster, George J.; Skorpik, James R.

    1997-01-01

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part.

  19. Ultrasonic material hardness depth measurement

    DOEpatents

    Good, M.S.; Schuster, G.J.; Skorpik, J.R.

    1997-07-08

    The invention is an ultrasonic surface hardness depth measurement apparatus and method permitting rapid determination of hardness depth of shafts, rods, tubes and other cylindrical parts. The apparatus of the invention has a part handler, sensor, ultrasonic electronics component, computer, computer instruction sets, and may include a display screen. The part handler has a vessel filled with a couplant, and a part rotator for rotating a cylindrical metal part with respect to the sensor. The part handler further has a surface follower upon which the sensor is mounted, thereby maintaining a constant distance between the sensor and the exterior surface of the cylindrical metal part. The sensor is mounted so that a front surface of the sensor is within the vessel with couplant between the front surface of the sensor and the part. 12 figs.

  20. Effect of flour polymeric proteins on dough thermal properties and breadmaking characteristics for hard red spring wheat genotypes

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The aim of this research was to investigate the effect of variation of flour polymeric proteins on rheological properties of dough under continuous mixing and thermal treatment for hard red spring (HRS) wheat genotypes grown in North Dakota, USA. Flour polymeric proteins were analyzed by size exclus...

  1. Schwannoma of the hard palate

    PubMed Central

    Sahoo, Pradyumna Kumar; Mandal, Palash Kumar; Ghosh, Saradindu

    2014-01-01

    Schwannomas are benign encapsulated perineural tumors. The head and neck region is the most common site. Intraoral origin is seen in only 1% of cases, tongue being the most common site; its location in the palate is rare. We report a case of hard-palate schwannoma with bony erosion which was immunohistochemically confirmed. The tumor was excised completely intraorally. After two months of follow-up, the defect was found to be completely covered with palatal mucosa. PMID:25298716

  2. Rad-Hard Silicon Detectors

    NASA Astrophysics Data System (ADS)

    Giorgi, Marco

    2005-06-01

    For the next generation of High Energy Physics (HEP) Experiments silicon microstrip detectors working in harsh radiation environments with excellent performances are necessary. The irradiation causes bulk and surface damages that modify the electrical properties of the detector. Solutions like AC coupled strips, overhanging metal contact, <100> crystal lattice orientation, low resistivity n-bulk and Oxygenated substrate are studied for rad-hard detectors. The paper presents an outlook of these technologies.

  3. Microwave assisted hard rock cutting

    DOEpatents

    Lindroth, David P.; Morrell, Roger J.; Blair, James R.

    1991-01-01

    An apparatus for the sequential fracturing and cutting of subsurface volume of hard rock (102) in the strata (101) of a mining environment (100) by subjecting the volume of rock to a beam (25) of microwave energy to fracture the subsurface volume of rock by differential expansion; and , then bringing the cutting edge (52) of a piece of conventional mining machinery (50) into contact with the fractured rock (102).

  4. Cooperation induced by random sequential exclusion

    NASA Astrophysics Data System (ADS)

    Li, Kun; Cong, Rui; Wang, Long

    2016-06-01

    Social exclusion is a common and powerful tool to penalize deviators in human societies, and thus to effectively elevate collaborative efforts. Current models on the evolution of exclusion behaviors mostly assume that each peer excluder independently makes the decision to expel the defectors, but has no idea what others in the group would do or how the actual punishment effect will be. Thus, a more realistic model, random sequential exclusion, is proposed. In this mechanism, each excluder has to pay an extra scheduling cost and then all the excluders are arranged in a random order to implement the exclusion actions. If one free rider has already been excluded by an excluder, the remaining excluders will not participate in expelling this defector. We find that this mechanism can help stabilize cooperation under more unfavorable conditions than the normal peer exclusion can do, either in well-mixed population or on social networks. However, too large a scheduling cost may undermine the advantage of this mechanism. Our work validates the fact that collaborative practice among punishers plays an important role in further boosting cooperation.

  5. Why Are Drugs So Hard to Quit?

    MedlinePlus Videos and Cool Tools

    ... Quitting drugs is hard because addiction is a brain disease. Your brain is like a control tower that sends out ... and choices. Addiction changes the signals in your brain and makes it hard to feel OK without ...

  6. More Older Women Hitting the Bottle Hard

    MedlinePlus

    ... medlineplus.gov/news/fullstory_164321.html More Older Women Hitting the Bottle Hard Study found dramatic jump ... March 28, 2017 (HealthDay News) -- More older American women than ever are drinking -- and drinking hard, a ...

  7. 42 CFR 402.13 - Penalty, assessment, and exclusion not exclusive.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Penalty, assessment, and exclusion not exclusive. 402.13 Section 402.13 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND... imposed under this part are in addition to any other penalties prescribed by law....

  8. 42 CFR 1003.108 - Penalty, assessment, and exclusion not exclusive.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Penalty, assessment, and exclusion not exclusive. 1003.108 Section 1003.108 Public Health OFFICE OF INSPECTOR GENERAL-HEALTH CARE, DEPARTMENT OF HEALTH... this part are in addition to any other penalties prescribed by law....

  9. 42 CFR 1003.108 - Penalty, assessment, and exclusion not exclusive.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 5 2013-10-01 2013-10-01 false Penalty, assessment, and exclusion not exclusive. 1003.108 Section 1003.108 Public Health OFFICE OF INSPECTOR GENERAL-HEALTH CARE, DEPARTMENT OF HEALTH... this part are in addition to any other penalties prescribed by law....

  10. 42 CFR 402.13 - Penalty, assessment, and exclusion not exclusive.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Penalty, assessment, and exclusion not exclusive. 402.13 Section 402.13 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND... imposed under this part are in addition to any other penalties prescribed by law....

  11. Ion exclusion chromatography of aromatic acids.

    PubMed

    Mansour, Fotouh R; Kirkpatrick, Christine L; Danielson, Neil D

    2013-08-01

    The determination of aromatic acids by ion exclusion chromatography is challenging due to peak tailing and the long retention time of hydrophobic solutes. This review discusses the retention mechanisms and the factors affecting retention, eluents and detection methods used in ion exclusion chromatography of aromatic acids such as mono-, di-, tri- and tetra-carboxylic acids, amino acids, sulfonates and phenol. In addition, the different approaches used to improve the chromatographic separation of these compounds are also discussed. These approaches include introducing an internal gradient of the ionic strength, using vacancy ion exclusion chromatography, employing a hydrophilic cation exchange resin or adding a modifier such as heptanol to the dilute sulfuric acid mobile phase. The applications of these methods in the analysis of aromatic acids are provided with a table summarizing the stationary phases, the mobile phases and the detection methods.

  12. Reggeometry of lepton- and hadron-induced reactions

    SciTech Connect

    Fiore, Roberto; Jenkovszky, Laszlo; Lavorini, Adelmo; Salii, Andrii

    2013-04-15

    We append a simple Pomeron pole amplitude by t and Q{sup 2}, MV dependencies inspired by geometrical ideas. The experimentally transition from soft to hard dynamics is realized by the introduction of a two-component Pomeron with different Q{sup 2} and M{sub V}-dependent residues. A unified description of deeply virtual Compton scattering (DVCS), of exclusive electroproduction of all vector mesons as well as of elastic pp scattering is suggested.

  13. Reggeometry of lepton- and hadron-induced reactions

    NASA Astrophysics Data System (ADS)

    Fiore, Roberto; Jenkovszky, László; Lavorini, Adelmo; Salii, Andrii

    2013-04-01

    We append a simple Pomeron pole amplitude by t and Q2, MV dependencies inspired by geometrical ideas. The experimentally transition from soft to hard dynamics is realized by the introduction of a two-component Pomeron with different Q2 and MV-dependent residues. A unified description of deeply virtual Compton scattering (DVCS), of exclusive electroproduction of all vector mesons as well as of elastic pp scattering is suggested.

  14. Warren G. Harding and the Press.

    ERIC Educational Resources Information Center

    Whitaker, W. Richard

    There are many parallels between the Richard M. Nixon administration and Warren G. Harding's term: both Republicans, both touched by scandal, and both having a unique relationship with the press. But in Harding's case the relationship was a positive one. One of Harding's first official acts as president was to restore the regular White House news…

  15. 30 CFR 56.15002 - Hard hats.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hard hats. 56.15002 Section 56.15002 Mineral... HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Personal Protection § 56.15002 Hard hats. All persons shall wear suitable hard hats when in or around a mine or plant where falling...

  16. 30 CFR 57.15002 - Hard hats.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hard hats. 57.15002 Section 57.15002 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Underground § 57.15002 Hard hats. All persons shall wear suitable hard hats when in or around a mine or...

  17. 7 CFR 201.21 - Hard seed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Hard seed. 201.21 Section 201.21 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Agricultural Seeds § 201.21 Hard seed. The label shall show the percentage of hard...

  18. 7 CFR 201.30 - Hard seed.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Hard seed. 201.30 Section 201.30 Agriculture..., Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED) FEDERAL SEED ACT FEDERAL SEED ACT REGULATIONS Labeling Vegetable Seeds § 201.30 Hard seed. The label shall show the percentage of hard seed,...

  19. 7 CFR 201.57 - Hard seeds.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... REGULATIONS Germination Tests in the Administration of the Act § 201.57 Hard seeds. Seeds which remain hard at..., are to be counted as “hard seed.” If at the end of the germination period provided for legumes, okra... percentage of germination. For flatpea, continue the swollen seed in test for 14 days when germinating at...

  20. 7 CFR 201.57 - Hard seeds.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... REGULATIONS Germination Tests in the Administration of the Act § 201.57 Hard seeds. Seeds which remain hard at..., are to be counted as “hard seed.” If at the end of the germination period provided for legumes, okra... percentage of germination. For flatpea, continue the swollen seed in test for 14 days when germinating at...

  1. 7 CFR 201.57 - Hard seeds.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... REGULATIONS Germination Tests in the Administration of the Act § 201.57 Hard seeds. Seeds which remain hard at..., are to be counted as “hard seed.” If at the end of the germination period provided for legumes, okra... percentage of germination. For flatpea, continue the swollen seed in test for 14 days when germinating at...

  2. 7 CFR 201.57 - Hard seeds.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... REGULATIONS Germination Tests in the Administration of the Act § 201.57 Hard seeds. Seeds which remain hard at..., are to be counted as “hard seed.” If at the end of the germination period provided for legumes, okra... percentage of germination. For flatpea, continue the swollen seed in test for 14 days when germinating at...

  3. 7 CFR 201.57 - Hard seeds.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... REGULATIONS Germination Tests in the Administration of the Act § 201.57 Hard seeds. Seeds which remain hard at..., are to be counted as “hard seed.” If at the end of the germination period provided for legumes, okra... percentage of germination. For flatpea, continue the swollen seed in test for 14 days when germinating at...

  4. Recoil Polarization Measurements for Neutral Pion Electroproduction at Q^2=1 (GeV/c)^2 Near the Delta Resonance

    SciTech Connect

    James Kelly; et. Al.

    2005-09-01

    We measured angular distributions of differential cross section, beam analyzing power, and recoil polarization for neutral pion electroproduction at Q{sup 2} = 1.0 (GeV/c){sup 2} in 10 bins of W across the Delta resonance. A total of 16 independent response functions were extracted, of which 12 were observed for the first time. Comparisons with recent model calculations show that response functions governed by real parts of interference products are determined relatively well near 1.232 GeV, but variations among models is large for response functions governed by imaginary parts and for both increases rapidly with W. We performed a nearly model-independent multipole analysis that adjusts complex multipoles with high partial waves constrained by baseline models. Parabolic fits to the W dependence of the multipole analysis around the Delta mass gives values for SMR = (-6.61 +/- 0.18)% and EMR = (-2.87 +/- 0.19)% that are distinctly larger than those from Legendre analysis of the same data. Similarly, the multipole analysis gives Re(S0+/M1+) = (+7.1 +/- 0.8)% at W=1.232 GeV, consistent with recent models, while the traditional Legendre analysis gives the opposite sign because its truncation errors are quite severe. Finally, using a unitary isobar model (UIM), we find that excitation of the Roper resonance is dominantly longitudinal with S1/2 = (0.05 +/- 0.01) GeV{sup (-1/2)} at Q{sup 2}=1. The ReS0+ and ReE0+ multipoles favor pseudovector coupling over pseudoscalar coupling or a recently proposed mixed-coupling scheme, but the UIM does not reproduce the imaginary parts of 0+ multipoles well.

  5. 42 CFR 402.209 - Scope and effect of exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Scope and effect of exclusion. 402.209 Section 402.209 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CIVIL MONEY PENALTIES, ASSESSMENTS, AND EXCLUSIONS Exclusions § 402.209 Scope and effect of exclusion. (a) Scope of...

  6. 42 CFR 402.214 - Appeal of exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CIVIL MONEY PENALTIES, ASSESSMENTS, AND EXCLUSIONS Exclusions § 402.214 Appeal of exclusion. (a... defenses that the person intends to assert. (4) Reasons why the proposed length of exclusion should...

  7. 42 CFR 402.214 - Appeal of exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL PROVISIONS CIVIL MONEY PENALTIES, ASSESSMENTS, AND EXCLUSIONS Exclusions § 402.214 Appeal of exclusion. (a... defenses that the person intends to assert. (4) Reasons why the proposed length of exclusion should...

  8. 42 CFR 402.209 - Scope and effect of exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 2 2014-10-01 2014-10-01 false Scope and effect of exclusion. 402.209 Section 402... effect of exclusion. (a) Scope of exclusion. Under this title, persons may be excluded from the Medicare, Medicaid, and, where applicable, any other Federal health care programs. (b) Effect of exclusion on...

  9. Evidence for high mass exclusive dijet production in the D0 experiment

    SciTech Connect

    Hubacek, Zdenek; /Prague, Tech. U.

    2010-10-01

    Exclusive diffractive Higgs boson production is an interesting process which could be studied at the Large Hadron Collider. While the cross section for the Higgs boson production at the Fermilab Tevatron Collider is too low for this channel, it is important to check if the class of exclusive diffraction events exists. We present the evidence for the high mass exclusive dijet production in the D0 experiment. Hard diffractive processes are usually described by the exchange of a colorless object called Pomeron. In diffractive hadron hadron collisions, the hadrons will exchange the Pomeron and either one or both hadrons will not dissolve. The events are identified by either a presence of a large forward region of the detector devoid of any activity (rapidity gap) or by a tagging of the intact beam hadron(s). A subset of diffractive events is called exclusive when the whole Pomeron energy is used to produce the diffractive state, i.e there are no Pomeron remnants. Exclusive diffractive production (EDP) of the Higgs boson or any other new final state X pp {yields} p + X + p has been recently proposed as a search channel at the LHC. The cross section for the Higgs boson production is too low at the Tevatron (0.2fb is predicted for a Higgs boson mass of 120 GeV), but it is important to check if this class of events exists in this kinematic region. The CDF Collaboration has recently confirmed the existence of EDP in several channels. In this report, we present the evidence for the exclusive production of high dijet invariant mass events, i.e. a dijet event accompanied by large rapidity gaps on both sides of the calorimeter.

  10. The Hard Problem of Cooperation

    PubMed Central

    Eriksson, Kimmo; Strimling, Pontus

    2012-01-01

    Based on individual variation in cooperative inclinations, we define the “hard problem of cooperation” as that of achieving high levels of cooperation in a group of non-cooperative types. Can the hard problem be solved by institutions with monitoring and sanctions? In a laboratory experiment we find that the answer is affirmative if the institution is imposed on the group but negative if development of the institution is left to the group to vote on. In the experiment, participants were divided into groups of either cooperative types or non-cooperative types depending on their behavior in a public goods game. In these homogeneous groups they repeatedly played a public goods game regulated by an institution that incorporated several of the key properties identified by Ostrom: operational rules, monitoring, rewards, punishments, and (in one condition) change of rules. When change of rules was not possible and punishments were set to be high, groups of both types generally abided by operational rules demanding high contributions to the common good, and thereby achieved high levels of payoffs. Under less severe rules, both types of groups did worse but non-cooperative types did worst. Thus, non-cooperative groups profited the most from being governed by an institution demanding high contributions and employing high punishments. Nevertheless, in a condition where change of rules through voting was made possible, development of the institution in this direction was more often voted down in groups of non-cooperative types. We discuss the relevance of the hard problem and fit our results into a bigger picture of institutional and individual determinants of cooperative behavior. PMID:22792282

  11. The hard problem of cooperation.

    PubMed

    Eriksson, Kimmo; Strimling, Pontus

    2012-01-01

    Based on individual variation in cooperative inclinations, we define the "hard problem of cooperation" as that of achieving high levels of cooperation in a group of non-cooperative types. Can the hard problem be solved by institutions with monitoring and sanctions? In a laboratory experiment we find that the answer is affirmative if the institution is imposed on the group but negative if development of the institution is left to the group to vote on. In the experiment, participants were divided into groups of either cooperative types or non-cooperative types depending on their behavior in a public goods game. In these homogeneous groups they repeatedly played a public goods game regulated by an institution that incorporated several of the key properties identified by Ostrom: operational rules, monitoring, rewards, punishments, and (in one condition) change of rules. When change of rules was not possible and punishments were set to be high, groups of both types generally abided by operational rules demanding high contributions to the common good, and thereby achieved high levels of payoffs. Under less severe rules, both types of groups did worse but non-cooperative types did worst. Thus, non-cooperative groups profited the most from being governed by an institution demanding high contributions and employing high punishments. Nevertheless, in a condition where change of rules through voting was made possible, development of the institution in this direction was more often voted down in groups of non-cooperative types. We discuss the relevance of the hard problem and fit our results into a bigger picture of institutional and individual determinants of cooperative behavior.

  12. Virtual Compton scattering and neutral pion electroproduction in the resonance region up to the deep inelastic region at backward angles

    SciTech Connect

    Laveissiere, Geraud; Degrande, Natalie; Jaminion, Stephanie; Jutier, Christophe; Todor, Luminita; Di Salvo, Rachele; Van Hoorebeke, L.; Alexa, L.C.; Anderson, Brian; Aniol, Konrad; Arundell, Kathleen; Audit, Gerard; Auerbach, Leonard; Baker, F.; Baylac, Maud; Berthot, J.; Bertin, Pierre; Bertozzi, William; Bimbot, Louis; Boeglin, Werner; Brash, Edward; Breton, Vincent; Breuer, Herbert; Burtin, Etienne; Calarco, John; Cardman, Lawrence; Cavata, Christian; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chang, C.; Chang, C.C.; Chen, Jian-Ping; Chudakov, Eugene; Cisbani, Evaristo; Dale, Daniel; De Jager, Cornelis; De Leo, Raffaele; Deur, Alexandre; D'Hose, Nicole; Dodge, Gail; Domingo, John; Elouadrhiri, Latifa; Epstein, Martin; Ewell, Lars; Finn, John; Fissum, Kevin; Fonvieille, Helene; Fournier, Guy; Frois, Bernard; Frullani, Salvatore; Furget, Christophe; Gao, Haiyan; Gao, Juncai; Garibaldi, Franco; Gasparian, Ashot; Gilad, Shalev; Gilman, Ronald; Glamazdin, Oleksandr; Glashausser, Charles; Gomez, Javier; Gorbenko, Viktor; Grenier, Philippe; Guichon, Pierre; Hansen, Jens-Ole; Holmes, Richard; Holtrop, Maurik; Howell, Calvin; Huber, Garth; Hyde, Charles; Incerti, Sebastien; Iodice, Mauro; Jardillier, Johann; Jones, Mark; Kahl, William; Kamalov, Sabit; Kato, Seigo; Katramatou, A.T.; Kelly, James; Kerhoas, Sophie; Ketikyan, Armen; Khayat, Mohammad; Kino, Kouichi; Kox, Serge; Kramer, Laird; Kumar, Krishna; Kumbartzki, Gerfried; Kuss, Michael; Leone, Antonio; LeRose, John; Liang, Meihua; Lindgren, Richard; Liyanage, Nilanga; Lolos, George; Lourie, Robert; Madey, Richard; Maeda, Kazushige; Malov, Sergey; Manley, D.; Marchand, Claude; Marchand, Dominique; Margaziotis, Demetrius; Markowitz, Pete; Marroncle, Jacques; Martino, Jacques; McCormick, Kathy; McIntyre, Justin; Mehrabyan, Surik; Merchez, Fernand; Meziani, Zein-Eddine; Michaels, Robert; Miller, Gerald; Mougey, Jean; Nanda, Sirish; Neyret, Damien; Offermann, Edmond; Papandreou, Zisis; Perdrisat, Charles; Perrino, R.; Petratos, Gerassimos; Platchkov, Stephane; Pomatsalyuk, Roman; Prout, David; Punjabi, Vina; Pussieux, Thierry; Quemener, Gilles; Ransome, Ronald; Ravel, Oliver; Real, Jean-Sebastien; Renard, F.; Roblin, Yves; Rowntree, David; Rutledge, Gary; Rutt, Paul; Saha, Arunava; Saito, Teijiro; Sarty, Adam; Serdarevic, A.; Smith, T.; Smirnov, G.; Soldi, K.; Sorokin, Pavel; Souder, Paul; Suleiman, Riad; Templon, Jeffrey; Terasawa, Tatsuo; Tiator, Lothar; Tieulent, Raphael; Tomasi-Gustaffson, E.; Tsubota, Hiroaki; Ueno, Hiroaki; Ulmer, Paul; Urciuoli, Guido; Van De Vyver, R.; van der Meer, Rob; Vernin, Pascal; Vlahovic, B.; Voskanyan, Hakob; Voutier, Eric; Watson, J.W.; Weinstein, Lawrence; Wijesooriya, Krishni; Wilson, R.; Wojtsekhowski, Bogdan; Zainea, Dan; Zhang, Wei-Ming; Zhao, Jie; Zhou, Z.-L.

    2009-01-01

    We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e,e'p)? exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the W-dependence at fixed Q2=1 GeV2, and for the Q2-dependence at fixed W near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed Q2-dependence is smooth. The measured ratio of H(e,e'p)? to H(e,e'p)?0 cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to Real Compton Scattering (RCS) at high energy and large angles, our VCS data at the highest W (1.8-1.9 GeV) show a striking Q2-independence, which may suggest a transition to a perturbative scattering mechanism at the quark level.

  13. Electroproduction of η Mesons in the S11(1535) Resonance Region at High Momentum Transfer

    SciTech Connect

    Dalton, Mark Macrae

    2008-08-01

    The differential cross-section for the exclusive process p(e, e0p) has been measured at Q2 5.7 and 7.0 (GeV/c)2, which represents the highest momentum transfer measurement of this to date, significantly higher than the previous highest at Q2 3.6 (GeV/c)2. Data was taken for centre-of-mass energies from threshold to 1.8 GeV, encompassing the S11(1535) resonance, which dominates the pη channel. The total cross section is obtained, from which is extracted the helicity-conserving transition amplitude A1/2, for the production of the S11(1535) resonance. This quantity appears to begin scaling as Q-3, a predicted signal of the dominance of perturbative QCD, within the Q2 range of this measurement. No currently available theoretical predictions can account for the behaviour of this quantity over the full measured range of Q2.

  14. Virtual Compton scattering and neutral pion electroproduction in the resonance region up to the deep inelastic region at backward angles

    SciTech Connect

    Laveissiere, G.; Jaminion, S.; Salvo, R. Di; Berthot, J.; Bertin, P. Y.; Breton, V.; Fonvieille, H.; Grenier, P.; Ravel, O.; Roblin, Y.; Smirnov, G.; Jutier, C.; Hyde, C. E.; Todor, L.; Dodge, G. E.; McCormick, K.; Ulmer, P. E.

    2009-01-15

    We have made the first measurements of the virtual Compton scattering (VCS) process via the H(e, e{sup '}p){gamma} exclusive reaction in the nucleon resonance region, at backward angles. Results are presented for the W-dependence at fixed Q{sup 2}=1 GeV{sup 2} and for the Q{sup 2} dependence at fixed W near 1.5 GeV. The VCS data show resonant structures in the first and second resonance regions. The observed Q{sup 2} dependence is smooth. The measured ratio of H(e, e{sup '}p){gamma} to H(e, e{sup '}p){pi}{sup 0} cross sections emphasizes the different sensitivity of these two reactions to the various nucleon resonances. Finally, when compared to real Compton scattering (RCS) at high energy and large angles, our VCS data at the highest W (1.8-1.9 GeV) show a striking Q{sup 2} independence, which may suggest a transition to a perturbative scattering mechanism at the quark level.

  15. Radiation Hardness Assurance (RHA) Guideline

    NASA Technical Reports Server (NTRS)

    Campola, Michael J.

    2016-01-01

    Radiation Hardness Assurance (RHA) consists of all activities undertaken to ensure that the electronics and materials of a space system perform to their design specifications after exposure to the mission space environment. The subset of interests for NEPP and the REAG, are EEE parts. It is important to register that all of these undertakings are in a feedback loop and require constant iteration and updating throughout the mission life. More detail can be found in the reference materials on applicable test data for usage on parts.

  16. Radiation hard electronics for LHC

    NASA Astrophysics Data System (ADS)

    Raymond, M.; Millmore, M.; Hall, G.; Sachdeva, R.; French, M.; Nygård, E.; Yoshioka, K.

    1995-02-01

    A CMOS front end electronics chain is being developed by the RD20 collaboration for microstrip detector readout at LHC. It is based on a preamplifier and CR-RC filter, analogue pipeline and an analogue signal processor. Amplifiers and transistor test structures have been constructed and evaluated in detail using a Harris 1.2 μm radiation hardened CMOS process. Progress with larger scale elements, including 32 channel front end chips, is described. A radiation hard 128 channel chip, with a 40 MHz analogue multiplexer, is to be submitted for fabrication in July 1994 which will form the basis of the readout of the tracking system of the CMS experiment.

  17. Hard Scattering Studies at Jlab

    SciTech Connect

    Harutyun Avagyan; Peter Bosted; Volker Burkert; Latifa Elouadrhiri

    2005-09-01

    We present current activities and future prospects for studies of hard scattering processes using the CLAS detector and the CEBAF polarized electron beam. Kinematic dependences of single and double spin asymmetries have been measured in a wide kinematic range at CLAS with a polarized NH{sub 3} and unpolarized liquid hydrogen targets. It has been shown that the data are consistent with factorization and observed target and beam asymmetries are in good agreement with measurements performed at higher energies, suggesting that the high energy-description of the semi-inclusive DIS process can be extended to the moderate energies of JLab measurements.

  18. Thermopile detector radiation hard readout

    NASA Astrophysics Data System (ADS)

    Gaalema, Stephen; Van Duyne, Stephen; Gates, James L.; Foote, Marc C.

    2010-08-01

    The NASA Jupiter Europa Orbiter (JEO) conceptual payload contains a thermal instrument with six different spectral bands ranging from 8μm to 100μm. The thermal instrument is based on multiple linear arrays of thermopile detectors that are intrinsically radiation hard; however, the thermopile CMOS readout needs to be hardened to tolerate the radiation sources of the JEO mission. Black Forest Engineering is developing a thermopile readout to tolerate the JEO mission radiation sources. The thermal instrument and ROIC process/design techniques are described to meet the JEO mission requirements.

  19. 40 CFR 503.6 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... treatment of domestic sewage in a treatment works. (i) Drinking water treatment sludge. This part does not... DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.6 Exclusions. (a) Treatment processes. This part does... requirements for the use or disposal of sludge generated at an industrial facility during the treatment...

  20. 40 CFR 503.6 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... treatment of domestic sewage in a treatment works. (i) Drinking water treatment sludge. This part does not... DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.6 Exclusions. (a) Treatment processes. This part does... requirements for the use or disposal of sludge generated at an industrial facility during the treatment...

  1. 40 CFR 503.6 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... treatment of domestic sewage in a treatment works. (i) Drinking water treatment sludge. This part does not... DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.6 Exclusions. (a) Treatment processes. This part does... requirements for the use or disposal of sludge generated at an industrial facility during the treatment...

  2. 40 CFR 503.6 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... treatment of domestic sewage in a treatment works. (i) Drinking water treatment sludge. This part does not... DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.6 Exclusions. (a) Treatment processes. This part does... requirements for the use or disposal of sludge generated at an industrial facility during the treatment...

  3. 40 CFR 503.6 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... treatment of domestic sewage in a treatment works. (i) Drinking water treatment sludge. This part does not... DISPOSAL OF SEWAGE SLUDGE General Provisions § 503.6 Exclusions. (a) Treatment processes. This part does... requirements for the use or disposal of sludge generated at an industrial facility during the treatment...

  4. 21 CFR 110.19 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 2 2013-04-01 2013-04-01 false Exclusions. 110.19 Section 110.19 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKING, OR HOLDING HUMAN FOOD...

  5. 21 CFR 110.19 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 2 2012-04-01 2012-04-01 false Exclusions. 110.19 Section 110.19 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKING, OR HOLDING HUMAN FOOD...

  6. 21 CFR 110.19 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 2 2011-04-01 2011-04-01 false Exclusions. 110.19 Section 110.19 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKING, OR HOLDING HUMAN FOOD...

  7. 40 CFR 763.99 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.99 Exclusions. (a) A local education agency shall not be... that school. (4) The lead agency responsible for asbestos inspection in a State that has been granted...

  8. 40 CFR 763.99 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.99 Exclusions. (a) A local education agency shall not be... that school. (4) The lead agency responsible for asbestos inspection in a State that has been granted...

  9. 40 CFR 763.99 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.99 Exclusions. (a) A local education agency shall not be... that school. (4) The lead agency responsible for asbestos inspection in a State that has been granted...

  10. 40 CFR 763.99 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.99 Exclusions. (a) A local education agency shall not be... that school. (4) The lead agency responsible for asbestos inspection in a State that has been granted...

  11. 40 CFR 763.99 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT ASBESTOS Asbestos-Containing Materials in Schools § 763.99 Exclusions. (a) A local education agency shall not be... that school. (4) The lead agency responsible for asbestos inspection in a State that has been granted...

  12. 24 CFR 58.35 - Categorical exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ..., except in extraordinary circumstances (see § 58.2(a)(3)) in which a normally excluded activity may have a... 24 Housing and Urban Development 1 2014-04-01 2014-04-01 false Categorical exclusions. 58.35 Section 58.35 Housing and Urban Development Office of the Secretary, Department of Housing and...

  13. 24 CFR 58.35 - Categorical exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., except in extraordinary circumstances (see § 58.2(a)(3)) in which a normally excluded activity may have a... 24 Housing and Urban Development 1 2013-04-01 2013-04-01 false Categorical exclusions. 58.35 Section 58.35 Housing and Urban Development Office of the Secretary, Department of Housing and...

  14. 24 CFR 58.35 - Categorical exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., except in extraordinary circumstances (see § 58.2(a)(3)) in which a normally excluded activity may have a... 24 Housing and Urban Development 1 2012-04-01 2012-04-01 false Categorical exclusions. 58.35 Section 58.35 Housing and Urban Development Office of the Secretary, Department of Housing and...

  15. 21 CFR 110.19 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 2 2014-04-01 2014-04-01 false Exclusions. 110.19 Section 110.19 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKING, OR HOLDING HUMAN FOOD...

  16. 32 CFR 220.3 - Exclusions impermissible.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 2 2013-07-01 2013-07-01 false Exclusions impermissible. 220.3 Section 220.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS COLLECTION FROM THIRD PARTY PAYERS OF REASONABLE CHARGES FOR HEALTHCARE SERVICES §...

  17. 32 CFR 220.3 - Exclusions impermissible.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 2 2014-07-01 2014-07-01 false Exclusions impermissible. 220.3 Section 220.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS COLLECTION FROM THIRD PARTY PAYERS OF REASONABLE CHARGES FOR HEALTHCARE SERVICES §...

  18. 32 CFR 220.3 - Exclusions impermissible.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 2 2012-07-01 2012-07-01 false Exclusions impermissible. 220.3 Section 220.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS COLLECTION FROM THIRD PARTY PAYERS OF REASONABLE CHARGES FOR HEALTHCARE SERVICES §...

  19. 49 CFR 236.911 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Exclusions. 236.911 Section 236.911 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND...

  20. 49 CFR 236.911 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Exclusions. 236.911 Section 236.911 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND...

  1. 49 CFR 236.911 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Exclusions. 236.911 Section 236.911 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND...

  2. 49 CFR 236.911 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Exclusions. 236.911 Section 236.911 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RULES, STANDARDS, AND INSTRUCTIONS GOVERNING THE INSTALLATION, INSPECTION, MAINTENANCE, AND...

  3. A Phenomenographical Study of Voluntary Digital Exclusion

    ERIC Educational Resources Information Center

    Anderson, Derrick L.

    2012-01-01

    Traditionally scholars have used the digital divide and technology acceptance model definitions when examining why some people elect not to use certain information and communications technologies. When examining the phenomenon referred to as voluntary digital exclusion, the use of these classic definitions is woefully inadequate. They do not…

  4. 40 CFR 1508.4 - Categorical exclusion.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... cumulatively have a significant effect on the human environment and which have been found to have no such... 40 Protection of Environment 33 2011-07-01 2011-07-01 false Categorical exclusion. 1508.4 Section 1508.4 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX §...

  5. 40 CFR 1508.4 - Categorical exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... cumulatively have a significant effect on the human environment and which have been found to have no such... 40 Protection of Environment 33 2014-07-01 2014-07-01 false Categorical exclusion. 1508.4 Section 1508.4 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX §...

  6. 40 CFR 1508.4 - Categorical exclusion.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... cumulatively have a significant effect on the human environment and which have been found to have no such... 40 Protection of Environment 34 2012-07-01 2012-07-01 false Categorical exclusion. 1508.4 Section 1508.4 Protection of Environment COUNCIL ON ENVIRONMENTAL QUALITY TERMINOLOGY AND INDEX §...

  7. 32 CFR 220.3 - Exclusions impermissible.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 2 2010-07-01 2010-07-01 false Exclusions impermissible. 220.3 Section 220.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS COLLECTION FROM THIRD PARTY PAYERS OF REASONABLE CHARGES FOR HEALTHCARE SERVICES §...

  8. 32 CFR 220.3 - Exclusions impermissible.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 2 2011-07-01 2011-07-01 false Exclusions impermissible. 220.3 Section 220.3 National Defense Department of Defense (Continued) OFFICE OF THE SECRETARY OF DEFENSE (CONTINUED) MISCELLANEOUS COLLECTION FROM THIRD PARTY PAYERS OF REASONABLE CHARGES FOR HEALTHCARE SERVICES §...

  9. 5 CFR 870.302 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Exclusions. 870.302 Section 870.302 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL... Pretrial Services, Parole, Adult Probation and Offender Supervision Trustee and employees of these...

  10. 5 CFR 846.712 - Statutory exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Statutory exclusions. 846.712 Section 846.712 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS... District of Columbia Pretrial Services, Defense Services, Parole, Adult Probation and Offender...

  11. 10 CFR 851.2 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., as set forth in Public Law 98-525, 42 U.S.C. 7158 note. (b) This part does not apply to radiological... ENERGY WORKER SAFETY AND HEALTH PROGRAM General Provisions § 851.2 Exclusions. (a) This part does not apply to work at a DOE site: (1) Regulated by the Occupational Safety and Health Administration; or...

  12. 10 CFR 851.2 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., as set forth in Public Law 98-525, 42 U.S.C. 7158 note. (b) This part does not apply to radiological... ENERGY WORKER SAFETY AND HEALTH PROGRAM General Provisions § 851.2 Exclusions. (a) This part does not apply to work at a DOE site: (1) Regulated by the Occupational Safety and Health Administration; or...

  13. Case Study of Chinese Exclusion Act Enforcement

    ERIC Educational Resources Information Center

    Dufour, Joanne, Comp.

    2012-01-01

    While nearly 85 percent of the U.S. population is currently made up of immigrants and their descendants, some groups were specifically targeted for exclusion and deliberately expelled. The Chinese were the first to experience this. In the 1850s, many Chinese who came to this land to search for gold or to help build the transcontinental railroad,…

  14. 48 CFR 832.404 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Section 832.404 Federal Acquisition Regulations System DEPARTMENT OF VETERANS AFFAIRS GENERAL CONTRACTING REQUIREMENTS CONTRACT FINANCING Advance Payments for Non-Commercial Items 832.404 Exclusions. (a) Under 31 U.S... payment for services and supplies obtained from another Government agency. (c) Under 5 U.S.C. 4109,...

  15. Citizenship Education in Turkey: Inclusive or Exclusive

    ERIC Educational Resources Information Center

    Ince, Basak

    2012-01-01

    This paper scrutinises citizenship education in Turkey from the foundation of the Turkish Republic (1923) to the present and explores the extent to which it encourages inclusive or exclusive concepts of national identity and citizenship. In Turkey, where there are citizens belonging to ethnic and religious minorities, civic education plays a…

  16. 41 CFR 109-28.5102 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false Exclusions. 109-28.5102 Section 109-28.5102 Public Contracts and Property Management Federal Property Management Regulations System (Continued) DEPARTMENT OF ENERGY PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT...

  17. 28 CFR 91.55 - Categorical exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., a proposed or listed endangered or threatened species, a proposed or listed critical habitat, a... that caused the loss of the exclusion. (a) Minor renovations. Projects for minor renovations within an...) Will affect a federally proposed or listed endangered or threatened species or its habitat; (5)...

  18. 21 CFR 110.19 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Exclusions. 110.19 Section 110.19 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CURRENT GOOD MANUFACTURING PRACTICE IN MANUFACTURING, PACKING, OR HOLDING HUMAN FOOD...

  19. New College Diversity Laws: Banning Racial Exclusion?

    ERIC Educational Resources Information Center

    Adam, Michelle

    2006-01-01

    Race-exclusive programs of American universities and colleges, created initially to level the playing fields for under-represented students in higher education, are now considered discriminatory and illegal. The concerns levied against higher education institutions have been in response to two 2003 U.S. Supreme Court cases on race and admission at…

  20. 43 CFR 20.302 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... and Payment of Travel and Related Expenses § 20.302 Exclusions. (a) Where employee travel is for... employee and/or the employee's spouse's travel from a non-Federal source when proper consideration is given... is issued in advance of the travel. (1) Conditions. Such travel expenses paid for by a...

  1. 43 CFR 20.302 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... and Payment of Travel and Related Expenses § 20.302 Exclusions. (a) Where employee travel is for... employee and/or the employee's spouse's travel from a non-Federal source when proper consideration is given... is issued in advance of the travel. (1) Conditions. Such travel expenses paid for by a...

  2. 43 CFR 20.302 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... and Payment of Travel and Related Expenses § 20.302 Exclusions. (a) Where employee travel is for... employee and/or the employee's spouse's travel from a non-Federal source when proper consideration is given... is issued in advance of the travel. (1) Conditions. Such travel expenses paid for by a...

  3. 29 CFR 9.4 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... amended. (2) Application to subcontracts. While the § 9.4(a)(1) exclusion applies to subcontracts that are...) of this section. (c) Federal service work constituting only part of employee's job. This part does... nonfederal service contracts as part of a single job, provided that the employees were not deployed in...

  4. 29 CFR 9.4 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Procurement Policy Act, as amended. (2) Application to subcontracts. While the § 9.4(a)(1) exclusion applies... paragraphs (b)(1)-(3) of this section. (c) Federal service work constituting only part of employee's job... or more nonfederal service contracts as part of a single job, provided that the employees were...

  5. 29 CFR 9.4 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...) Application to subcontracts. While the § 9.4(a)(1) exclusion applies to subcontracts that are less than the... section. (c) Federal service work constituting only part of employee's job. This part does not apply to... contracts as part of a single job, provided that the employees were not deployed in a manner that...

  6. 41 CFR 101-26.802 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...-Discrepancies or Deficiencies in GSA or DOD Shipments, Material, or Billings § 101-26.802 Exclusions. The provisions of this regulation are not applicable to shipments and billings related to the stockpile of strategic and critical materials or excess or surplus property; or to billings for services,...

  7. 41 CFR 101-26.802 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-Discrepancies or Deficiencies in GSA or DOD Shipments, Material, or Billings § 101-26.802 Exclusions. The provisions of this regulation are not applicable to shipments and billings related to the stockpile of strategic and critical materials or excess or surplus property; or to billings for services,...

  8. 41 CFR 101-26.802 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 2 2013-07-01 2012-07-01 true Exclusions. 101-26.802 Section 101-26.802 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 26-PROCUREMENT SOURCES AND PROGRAM...

  9. 41 CFR 101-26.802 - Exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 2 2014-07-01 2012-07-01 true Exclusions. 101-26.802 Section 101-26.802 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 26-PROCUREMENT SOURCES AND PROGRAM...

  10. 41 CFR 101-26.802 - Exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 2 2012-07-01 2012-07-01 false Exclusions. 101-26.802 Section 101-26.802 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS SUPPLY AND PROCUREMENT 26-PROCUREMENT SOURCES AND PROGRAM...

  11. Nano-fabricated size exclusion chromatograph

    NASA Technical Reports Server (NTRS)

    Svehla, D.; Feldman, S.; Feldman, J.; Grunthaner, F.; Shakkottai, P.; dle Castillo, L.; White, V.

    2002-01-01

    This poster describes the development of a nano-fabricated size exclusion chromatograph (nSEC) based on the principle that molecules traveling through a microcolumn containing nano-fabricated features will have characteristics elution times that directly correlate to molecular weight.

  12. 22 CFR 513.210 - Voluntary exclusion.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 22 Foreign Relations 2 2011-04-01 2009-04-01 true Voluntary exclusion. 513.210 Section 513.210 Foreign Relations BROADCASTING BOARD OF GOVERNORS GOVERNMENT DEBARMENT AND SUSPENSION (NONPROCUREMENT) AND GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Effect of Action § 513.210 Voluntary...

  13. 22 CFR 513.210 - Voluntary exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 22 Foreign Relations 2 2014-04-01 2014-04-01 false Voluntary exclusion. 513.210 Section 513.210 Foreign Relations BROADCASTING BOARD OF GOVERNORS GOVERNMENT DEBARMENT AND SUSPENSION (NONPROCUREMENT) AND GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Effect of Action § 513.210 Voluntary...

  14. 22 CFR 513.210 - Voluntary exclusion.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 22 Foreign Relations 2 2012-04-01 2009-04-01 true Voluntary exclusion. 513.210 Section 513.210 Foreign Relations BROADCASTING BOARD OF GOVERNORS GOVERNMENT DEBARMENT AND SUSPENSION (NONPROCUREMENT) AND GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Effect of Action § 513.210 Voluntary...

  15. 22 CFR 513.210 - Voluntary exclusion.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 22 Foreign Relations 2 2013-04-01 2009-04-01 true Voluntary exclusion. 513.210 Section 513.210 Foreign Relations BROADCASTING BOARD OF GOVERNORS GOVERNMENT DEBARMENT AND SUSPENSION (NONPROCUREMENT) AND GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Effect of Action § 513.210 Voluntary...

  16. 22 CFR 513.210 - Voluntary exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Voluntary exclusion. 513.210 Section 513.210 Foreign Relations BROADCASTING BOARD OF GOVERNORS GOVERNMENT DEBARMENT AND SUSPENSION (NONPROCUREMENT) AND GOVERNMENTWIDE REQUIREMENTS FOR DRUG-FREE WORKPLACE (GRANTS) Effect of Action § 513.210 Voluntary...

  17. 32 CFR 651.55 - Categorical exclusions.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Categorical exclusions. 651.55 Section 651.55 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Effects of Major Army Action Abroad §...

  18. 32 CFR 651.55 - Categorical exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Categorical exclusions. 651.55 Section 651.55 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Effects of Major Army Action Abroad §...

  19. 32 CFR 651.55 - Categorical exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Categorical exclusions. 651.55 Section 651.55 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Effects of Major Army Action Abroad §...

  20. 32 CFR 651.55 - Categorical exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Categorical exclusions. 651.55 Section 651.55 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Effects of Major Army Action Abroad §...

  1. 32 CFR 651.55 - Categorical exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Categorical exclusions. 651.55 Section 651.55 National Defense Department of Defense (Continued) DEPARTMENT OF THE ARMY (CONTINUED) ENVIRONMENTAL QUALITY ENVIRONMENTAL ANALYSIS OF ARMY ACTIONS (AR 200-2) Environmental Effects of Major Army Action Abroad §...

  2. 5 CFR 551.214 - Statutory exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Statutory exclusion. 551.214 Section 551.214 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS PAY... customs officer who receives overtime pay under subsection (a) or premium pay under subsection (b) of 19...

  3. 46 CFR 504.4 - Categorical exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... FEDERAL MARITIME COMMISSION GENERAL AND ADMINISTRATIVE PROVISIONS PROCEDURES FOR ENVIRONMENTAL POLICY ANALYSIS § 504.4 Categorical exclusions. (a) No environmental analyses need be undertaken or environmental... effect on the quality of the human environment because they are purely ministerial actions or...

  4. 46 CFR 504.4 - Categorical exclusions.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... FEDERAL MARITIME COMMISSION GENERAL AND ADMINISTRATIVE PROVISIONS PROCEDURES FOR ENVIRONMENTAL POLICY ANALYSIS § 504.4 Categorical exclusions. (a) No environmental analyses need be undertaken or environmental... effect on the quality of the human environment because they are purely ministerial actions or...

  5. 12 CFR 1815.110 - Categorical exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... ENVIRONMENTAL QUALITY § 1815.110 Categorical exclusion. The CEQ regulations provide for the categorical..., equipment, supplies and services; space acquisition; property management; and security); (b) Actions... replacement after rehabilitation; and (4) The Project does not involve the demolition of one or more...

  6. 12 CFR 1815.110 - Categorical exclusion.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... ENVIRONMENTAL QUALITY § 1815.110 Categorical exclusion. The CEQ regulations provide for the categorical..., equipment, supplies and services; space acquisition; property management; and security); (b) Actions... replacement after rehabilitation; and (4) The Project does not involve the demolition of one or more...

  7. Diffraction and central exclusive production at ATLAS

    SciTech Connect

    Tasevsky, Marek

    2011-07-15

    The diffractive physics program for the ATLAS experiment with an emphasis on the central exclusive production is discussed. The key point in this discussion is the need for an unambiguous experimental definition of diffractive signature which would be acceptable and reproducible by theorists. Recent ATLAS results from samples enhanced in diffraction contribution underline this need.

  8. Teaching the Exclusion Principle with Philosophical Flavor

    ERIC Educational Resources Information Center

    Shadmi, Y.

    1978-01-01

    Outlines an approach to the teaching of a chapter in a quantum mechanics course. The exclusion principle is confronted with the principle of the "identity of the indiscernible" of Leibnitz. Concludes that philosophy can never replace scientific research, thus predicting directions of advances of physical theories. (GA)

  9. 12 CFR 1815.110 - Categorical exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 7 2010-01-01 2010-01-01 false Categorical exclusion. 1815.110 Section 1815.110 Banks and Banking COMMUNITY DEVELOPMENT FINANCIAL INSTITUTIONS FUND, DEPARTMENT OF THE TREASURY... assessment and EIS have been prepared; (c) Actions directly related to the granting or receipt of...

  10. Sexism and Permanent Exclusion from School

    ERIC Educational Resources Information Center

    Carlile, Anna

    2009-01-01

    Focussing on narratives collected during a two year participant observation research project in the children's services department of an urban local authority, this article addresses the intersection between incidents of permanent exclusion from school and assumptions made on the basis of a young person's gender. The article considers gendered…

  11. 47 CFR 2.1202 - Exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Importation of Devices Capable of Causing Harmful Interference § 2.1202 Exclusions...) Radio frequency devices manufactured and assembled in the U.S.A. that meet applicable FCC...

  12. 47 CFR 2.1202 - Exclusions.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL FREQUENCY ALLOCATIONS AND RADIO TREATY MATTERS; GENERAL RULES AND REGULATIONS Importation of Devices Capable of Causing Harmful Interference § 2.1202 Exclusions...) Radio frequency devices manufactured and assembled in the U.S.A. that meet applicable FCC...

  13. Exclusive breakup measurements for {sup 9}Be

    SciTech Connect

    Fulton, B.R.; Cowin, R.L.; Woolliscroft, R.J.; Clarke, N.M.; Donadille, L.; Freer, M.; Leask, P.J.; Singer, S.M.; Nicoli, M.P.; Benoit, B.; Hanappe, F.; Ninane, A.; Orr, N.A.; Tillier, J.; Stuttge, L.

    2004-10-01

    The first exclusive breakup measurements for the nucleus {sup 9}Be are presented. Breakup via several discrete states is observed following scattering off {sup 12}C and {sup 208}Pb. The results support the prediction of a recent microscopic cluster calculation for a strong n+{sup 8}Be(2{sup +}) state component in the second excited state.

  14. 19 CFR 10.452 - Exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Exclusions. 10.452 Section 10.452 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY ARTICLES CONDITIONALLY FREE, SUBJECT TO A REDUCED RATE, ETC. United States-Chile Free Trade Agreement...

  15. 5 CFR 359.401 - General exclusions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false General exclusions. 359.401 Section 359.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REMOVAL FROM THE SENIOR EXECUTIVE SERVICE; GUARANTEED PLACEMENT IN OTHER PERSONNEL SYSTEMS Removal of Career...

  16. 5 CFR 359.401 - General exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false General exclusions. 359.401 Section 359.401 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS REMOVAL FROM THE SENIOR EXECUTIVE SERVICE; GUARANTEED PLACEMENT IN OTHER PERSONNEL SYSTEMS Removal of Career...

  17. Nucleon-to-Pion Transition Distribution Amplitudes: A Challenge for P¯ANDA

    NASA Astrophysics Data System (ADS)

    Pire, B.; Semenov-Tian-Shansky, K.; Szymanowski, L.

    2014-06-01

    Baryon-to-meson transition distribution amplitudes (TDAs) appear as building blocks in the collinear factorized description of amplitudes for a class of hard exclusive reactions, prominent examples being hard exclusive pion electroproduction off a nucleon in the backward region and baryon-antibaryon annihilation into a pion and a lepton pair or a charmonium. Baryon-to-meson TDAs extend both the concepts of generalized parton distributions and baryon distribution amplitudes encoding valuable complementary information on the hadronic structure. We review the basic properties of baryon-to-meson TDAs and discuss the perspectives for the experimental access with the P¯ANDA detector.

  18. Thermodynamic properties of lattice hard-sphere models.

    PubMed

    Panagiotopoulos, A Z

    2005-09-08

    Thermodynamic properties of several lattice hard-sphere models were obtained from grand canonical histogram- reweighting Monte Carlo simulations. Sphere centers occupy positions on a simple cubic lattice of unit spacing and exclude neighboring sites up to a distance sigma. The nearestneighbor exclusion model, sigma = radical2, was previously found to have a second-order transition. Models with integer values of sigma = 1 or 2 do not have any transitions. Models with sigma = radical3 and sigma = 3 have weak first-order fluid-solid transitions while those with sigma = 2 radical2, 2 radical3, and 3 radical2 have strong fluid-solid transitions. Pressure, chemical potential, and density are reported for all models and compared to the results for the continuum, theoretical predictions, and prior simulations when available.

  19. Hardness correlation for uranium and its alloys

    SciTech Connect

    Humphreys, D L; Romig, Jr, A D

    1983-03-01

    The hardness of 16 different uranium-titanium (U-Ti) alloys was measured on six (6) different hardness scales (R/sub A/, R/sub B/, R/sub C/, R/sub D/, Knoop, and Vickers). The alloys contained between 0.75 and 2.0 wt % Ti. All of the alloys were solutionized (850/sup 0/C, 1 h) and ice-water quenched to produce a supersaturated martensitic phase. A range of hardnesses was obtained by aging the samples for various times and temperatures. The correlation of various hardness scales was shown to be virtually identical to the hardness-scale correlation for steels. For more-accurate conversion from one hardness scale to another, least-squares-curve fits were determined for the various hardness-scale correlations. 34 figures, 5 tables.

  20. Unnecessary Child Care Exclusions in a State That Endorses National Exclusion Guidelines

    PubMed Central

    Hashikawa, Andrew N.; Juhn, Young J.; Nimmer, Mark; Copeland, Kristen; Shun-Hwa, Li; Simpson, Pippa; Stevens, Martha W.; Brousseau, David C.

    2011-01-01

    OBJECTIVE No study has evaluated the association between state endorsement of American Academy of Pediatrics (AAP) and American Public Health Association (APHA) national guidelines and unnecessary exclusion decisions. We sought to determine the rate of unnecessary exclusion decisions by child care directors in a state that endorses AAP/APHA guidelines and to identify factors that are associated with higher unnecessary exclusion decisions. METHODS A telephone survey was administered to directors in metropolitan Milwaukee, Wisconsin. Directors were randomly sampled from a list of 971 registered centers. Director, center, and neighborhood characteristics were obtained. Directors reported whether immediate exclusion was indicated for 5 vignettes that featured children with mild illness that do not require exclusion by AAP/APHA guidelines. Weighted data were summarized by using descriptive statistics. Regression analysis was used to identify factors that were associated with directors’ exclusion decisions. RESULTS A total of 305 directors completed the survey. Overall, directors would unnecessarily exclude 57% of children. More than 62% had never heard of the AAP/APHA guidelines. Regression analysis showed fewer exclusions among more experienced compared with less experienced directors, among larger centers compared with smaller centers, and among centers that were located in areas with a higher percentage of female heads of household. Centers with ≤10% children on state-assisted tuition excluded more. CONCLUSIONS High rates of inappropriate exclusion persist despite state endorsement of AAP/APHA guidelines. Focused initial and ongoing training of directors regarding AAP/APHA guidelines may help to reduce high rates of unnecessary exclusions. PMID:20403929

  1. Hard and Soft Safety Verifications

    NASA Technical Reports Server (NTRS)

    Wetherholt, Jon; Anderson, Brenda

    2012-01-01

    The purpose of this paper is to examine the differences between and the effects of hard and soft safety verifications. Initially, the terminology should be defined and clarified. A hard safety verification is datum which demonstrates how a safety control is enacted. An example of this is relief valve testing. A soft safety verification is something which is usually described as nice to have but it is not necessary to prove safe operation. An example of a soft verification is the loss of the Solid Rocket Booster (SRB) casings from Shuttle flight, STS-4. When the main parachutes failed, the casings impacted the water and sank. In the nose cap of the SRBs, video cameras recorded the release of the parachutes to determine safe operation and to provide information for potential anomaly resolution. Generally, examination of the casings and nozzles contributed to understanding of the newly developed boosters and their operation. Safety verification of SRB operation was demonstrated by examination for erosion or wear of the casings and nozzle. Loss of the SRBs and associated data did not delay the launch of the next Shuttle flight.

  2. Density functional theory for nearest-neighbor exclusion lattice gases in two and three dimensions

    NASA Astrophysics Data System (ADS)

    Lafuente, Luis; Cuesta, José A.

    2003-12-01

    To speak about fundamental measure theory obliges us to mention dimensional crossover. This feature, inherent to the systems themselves, was incorporated in the theory almost from the beginning. Although at first it was thought to be a consistency check for the theory, it rapidly became its fundamental pillar, thus becoming the only density functional theory which possesses such a property. It is straightforward that dimensional crossover connects, for instance, the parallel hard cube system (three dimensional) with that of squares (two dimensional) and rods (one dimensional). We show here that there are many more connections which can be established in this way. Through them we deduce from the functional for parallel hard (hyper)cubes in the simple (hyper)cubic lattice the corresponding functionals for the nearest-neighbor exclusion lattice gases in the square, triangular, simple cubic, face-centered-cubic, and body-centered-cubic lattices. As an application, the bulk phase diagram for all these systems is obtained.

  3. Exclusive meson pair production in {gamma}*{gamma} scattering at small momentum transfer

    SciTech Connect

    Lansberg, J.P.; Pire, B.; Szymanowski, L.

    2006-04-01

    We study the exclusive production of {pi}{pi} and {rho}{pi} in hard {gamma}*{gamma} scattering in the forward kinematical region where the virtuality of one photon provides us with a hard scale in the process. The newly introduced concept of Transition Distribution Amplitudes (TDA) is used to perform a QCD calculation of these reactions thanks to two simple models for TDAs. Cross sections for {rho}{pi} and {pi}{pi} production are evaluated and compared to the possible background from the Bremsstrahlung process. This picture may be tested at intense electron-positron colliders such as CLEO and B factories. The cross section e{gamma}{yields}e{sup '}{pi}{sup 0}{pi}{sup 0} is finally shown to provide a possible determination of the {pi}{sup 0} axial form factor, F{sub A}{sup {pi}{sup 0}}, at small t, which seems not to be measurable elsewhere.

  4. Development of radiation hard scintillators

    SciTech Connect

    Markley, F.; Woods, D.; Pla-Dalmau, A.; Foster, G. ); Blackburn, R. )

    1992-05-01

    Substantial improvements have been made in the radiation hardness of plastic scintillators. Cylinders of scintillating materials 2.2 cm in diameter and 1 cm thick have been exposed to 10 Mrads of gamma rays at a dose rate of 1 Mrad/h in a nitrogen atmosphere. One of the formulations tested showed an immediate decrease in pulse height of only 4% and has remained stable for 12 days while annealing in air. By comparison a commercial PVT scintillator showed an immediate decrease of 58% and after 43 days of annealing in air it improved to a 14% loss. The formulated sample consisted of 70 parts by weight of Dow polystyrene, 30 pbw of pentaphenyltrimethyltrisiloxane (Dow Corning DC 705 oil), 2 pbw of p-terphenyl, 0.2 pbw of tetraphenylbutadiene, and 0.5 pbw of UVASIL299LM from Ferro.

  5. Hard X-ray astrophysics

    NASA Technical Reports Server (NTRS)

    Rothschild, R. E.

    1981-01-01

    Past hard X-ray and lower energy satellite instruments are reviewed and it is shown that observation above 20 keV and up to hundreds of keV can provide much valuable information on the astrophysics of cosmic sources. To calculate possible sensitivities of future arrays, the efficiencies of a one-atmosphere inch gas counter (the HEAO-1 A-2 xenon filled HED3) and a 3 mm phoswich scintillator (the HEAO-1 A-4 Na1 LED1) were compared. Above 15 keV, the scintillator was more efficient. In a similar comparison, the sensitivity of germanium detectors did not differ much from that of the scintillators, except at high energies where the sensitivity would remain flat and not rise with loss of efficiency. Questions to be addressed concerning the physics of active galaxies and the diffuse radiation background, black holes, radio pulsars, X-ray pulsars, and galactic clusters are examined.

  6. A study of Central Exclusive Production

    SciTech Connect

    Monk, James

    2006-01-01

    Central exclusive production of a system X in a collision between two hadrons h is defined as hh → h + X + h with no other activity apart from the decay products of X. This thesis presents predictions for the production cross section of a CP violating supersymmetric Higgs boson and the radion of the Randall-Sundrum model. The ExHuME Monte Carlo generator was written to simulate central exclusive processes and is described and explored. A comparison to di-jet observations made by the D0 detector at the Tevatron, Fermilab between January and June 2004 is made and the distributions found support the predictions of ExHuME.

  7. Exclusive hadronic decays of B mesons

    NASA Astrophysics Data System (ADS)

    Hölscher, Andreas

    1991-06-01

    The recent experimental results on exclusive hadronic decays of B mesons obtained by the ARGUS collaboration are presented in the talk. The results include exclusive hadronic decays involving a b → c transition, namely B decays with a D, D ∗ plus several pions and B decays to J/ψ or ψ' mesons plus Kaons have been studied. The measurements of branching ratios for two-body B decays involving a J/ψ or ψ' meson are of wide interest in the light of proposals for the study of CP violation in future experiments. The branching ratios are compared with the predictions of the model of Bauer, Stech and Wirbel and with a model of A.V. Dobrovolskaya. Using the cleanest decay channels, the masses and mass difference of the charged and neutral B meson are obtained. This mass difference is then compared with the mass splitting in other isospinmultipletts and with theoretical models.

  8. Gendered racial exclusion among White internet daters.

    PubMed

    Feliciano, Cynthia; Robnett, Belinda; Komaie, Golnaz

    2009-03-01

    Acceptance by the dominant group reveals the current standing of racial groups in the U.S. hierarchy, as well as the possibility for assimilation. However, few researchers have addressed the gendered nature of racial preferences by whites. We examine whites' exclusion of blacks, Latinos, Asians, Middle Easterners, East Indians and Native Americans as possible dates, using a sample of profiles collected from an internet dating website. We find that white men are more willing than white women to date non-whites in general, yet, with the exception of their top two preferences for dates, whites and Latinos, the racial hierarchies of males and females differ. Among daters with stated racial preferences, white men are more likely to exclude blacks as possible dates, while white women are more likely to exclude Asians. We argue that exclusion relates to racialized images of masculinity and femininity, and shapes dating and marriage outcomes, and thus minority groups' possibilities for full social incorporation.

  9. Mesoscopic full counting statistics and exclusion models

    NASA Astrophysics Data System (ADS)

    Roche, P.-E.; Derrida, B.; Douçot, B.

    2005-02-01

    We calculate the distribution of current fluctuations in two simple exclusion models. Although these models are classical, we recover even for small systems such as a simple or a double barrier, the same distibution of current as given by traditional formalisms for quantum mesoscopic conductors. Due to their simplicity, the full counting statistics in exclusion models can be reduced to the calculation of the largest eigenvalue of a matrix, the size of which is the number of internal configurations of the system. As examples, we derive the shot noise power and higher order statistics of current fluctuations (skewness, full counting statistics, ....) of various conductors, including multiple barriers, diffusive islands between tunnel barriers and diffusive media. A special attention is dedicated to the third cumulant, which experimental measurability has been demonstrated lately.

  10. Exclusive nonleptonic B→VV decays

    NASA Astrophysics Data System (ADS)

    Barik, N.; Naimuddin, Sk.; Dash, P. C.; Kar, Susmita

    2009-07-01

    The exclusive two-body nonleptonic B→VV decays are investigated, within the factorization approximation, in the relativistic independent quark model based on a confining potential in the scalar-vector harmonic form. The branching ratios and the logitudinal polarization fraction (RL) are calculated yielding the model predictions in agreement with experiment. Our predicted CP-odd fraction (R⊥) for B→D*D(s)* decays are in general agreement with other model predictions and within the existing experimental limit.

  11. Haldane exclusion statistics and second virial coefficient

    SciTech Connect

    Murthy, M.V.N.; Shankar, R. )

    1994-06-06

    We show that Haldane's new definition of statistics, when generalized to infinite dimensional Hilbert spaces, is determined by the high temperature limit of the second virial coefficient. We thus show that this exclusion statistics parameter [ital g] of anyone is nontrivial and is completely determined by its exchange statistics parameter [alpha]. We also compute [ital g] for quasiparticles in the Luttinger model and show that it is equal to [alpha].

  12. Combat Exclusion: An Equal Protection Analysis

    DTIC Science & Technology

    1997-04-01

    uniforms, they served without the benefits of rank, officer status, equal pay , or veteran’s benefits. The Army also contracted women to serve in the Signal...accomplish the elimination of hearings on the merits, is to make the very kind of arbitrary legislative choice forbidden by the Equal Protection...wUGmm’" LOAN DOCUMENT * COMBAT EXCLUSION: AN EQUAL PROTECTION ANALYSIS A Thesis Presented to The Judge Advocate General’s School United States Army The

  13. The Asymmetric Exclusion Process and Brownian Excursions

    NASA Astrophysics Data System (ADS)

    Derrida, B.; Enaud, C.; Lebowitz, J. L.

    2004-04-01

    We consider the totally asymmetric exclusion process (TASEP) in one dimension in its maximal current phase. We show, by an exact calculation, that the non-Gaussian part of the fluctuations of density can be described in terms of the statistical properties of a Brownian excursion. Numerical simulations indicate that the description in terms of a Brownian excursion remains valid for more general one dimensional driven systems in their maximal current phase.

  14. The evolution of cooperation by social exclusion

    PubMed Central

    Sasaki, Tatsuya; Uchida, Satoshi

    2013-01-01

    The exclusion of freeriders from common privileges or public acceptance is widely found in the real world. Current models on the evolution of cooperation with incentives mostly assume peer sanctioning, whereby a punisher imposes penalties on freeriders at a cost to itself. It is well known that such costly punishment has two substantial difficulties. First, a rare punishing cooperator barely subverts the asocial society of freeriders, and second, natural selection often eliminates punishing cooperators in the presence of non-punishing cooperators (namely, ‘second-order’ freeriders). We present a game-theoretical model of social exclusion in which a punishing cooperator can exclude freeriders from benefit sharing. We show that such social exclusion can overcome the above-mentioned difficulties even if it is costly and stochastic. The results do not require a genetic relationship, repeated interaction, reputation or group selection. Instead, only a limited number of freeriders are required to prevent the second-order freeriders from eroding the social immune system. PMID:23222449

  15. Exclusion testing in pregnancy for Huntington's disease.

    PubMed Central

    Tyler, A; Quarrell, O W; Lazarou, L P; Meredith, A L; Harper, P S

    1990-01-01

    The results of DNA analysis are presented for a series of 90 couples, with one partner at 50% risk for Huntington's disease (HD), who were referred for exclusion testing in pregnancy over a three year period. Thirty-seven couples were studied in detail. The aims of the study were to evaluate attitudes towards prenatal testing, before pregnancy and afterwards, and the effectiveness of our counseling and methods of organising the service. Problems which could arise in relation to presymptomatic testing are documented. It is concluded that exclusion testing is a valuable form of prediction for some couples, particularly where family structure does not permit prediction for the person at risk. The need for intensive counselling was highlighted by the difficulties experienced by many couples in understanding how the test worked. Particular ethical and organisational problems may arise which require careful consideration beforehand and some recommendations are made. The proportion of couples who will continue to request exclusion testing as pre-symptomatic testing becomes more widely applicable remains unknown. PMID:2145437

  16. Density profiles of the exclusive queuing process

    NASA Astrophysics Data System (ADS)

    Arita, Chikashi; Schadschneider, Andreas

    2012-12-01

    The exclusive queuing process (EQP) incorporates the exclusion principle into classic queuing models. It is characterized by, in addition to the entrance probability α and exit probability β, a third parameter: the hopping probability p. The EQP can be interpreted as an exclusion process of variable system length. Its phase diagram in the parameter space (α,β) is divided into a convergent phase and a divergent phase by a critical line which consists of a curved part and a straight part. Here we extend previous studies of this phase diagram. We identify subphases in the divergent phase, which can be distinguished by means of the shape of the density profile, and determine the velocity of the system length growth. This is done for EQPs with different update rules (parallel, backward sequential and continuous time). We also investigate the dynamics of the system length and the number of customers on the critical line. They are diffusive or subdiffusive with non-universal exponents that also depend on the update rules.

  17. Habitat Suitability Index Models: Hard clam

    USGS Publications Warehouse

    Mulholland, Rosemarie

    1984-01-01

    Two species of hard clams occur along the Atlantic and Gulf of Mexico coasts of North America: the southern hard clam, Mercenaria campechiensis Gmelin 1791, and the northern hard clam, ~lercenaria mercenaria Linne 1758 (Wells 1957b). The latter species, also commonly kno\\'m as the quahog, was formerly named Venus mercenaria. The two species are closely related, produce viable hybrids (Menzel and Menzel 1965), and may be a single species.

  18. Measurement of the Unpolarized K+ Λ and K+ Σ0 Electroproduction Cross Sections and Interference Terms from the Proton with the CLAS Detector

    SciTech Connect

    Feuerbach, Robert J.

    2002-12-01

    Using the CLAS detector, we measure the K+ Λ and K+ Σ0 electroproduction response functions over the continuous kinematic range from threshold to W = 2.05 GeV and for Q2 between 0.5 and 1.5 (GeV/c)2, with nearly complete angular coverage in the center-of-momentum frame angles. The σT + ϵσL, σTT terms are extracted and compared to recent theoretical calculations based upon a hadrodynamic effective-Lagrangian framework. From examining the W-dependence of the response functions for the K+ Λ final state, we find features in the (σT + ϵσL) term in the W = 1.75 to 1.90GeV region, similar to features seen in recent photoproduction results. In general, the σTT and σLT response-functions for Λ production are of the same order of magnitude as the (σT + ϵσL) term, suggesting that both σT and σL contribute significantly. For the K+ Σ0 final state the W-dependence of the (σT + ϵσL) and σTT terms have large, resonant-like features near W = 1.9GeV. Unlike in Λ electroproduction, the σLT interference term for Σ0 electroproduction is found to be consistent with zero across nearly the entire kinematic range, while σTT is comparable in magnitude to the σT + ϵσL differential cross-section. The models, while achieving some qualitative agreement with the data, fail to both describe the details of the angular distributions and reproduce the resonant-like behavior observed.

  19. 30 CFR 77.1710-1 - Distinctively colored hard hats or hard caps; identification for newly employed, inexperienced...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Distinctively colored hard hats or hard caps... Distinctively colored hard hats or hard caps; identification for newly employed, inexperienced miners. Hard hats or hard caps distinctively different in color from those worn by experienced miners shall be worn...

  20. 30 CFR 75.1720-1 - Distinctively colored hard hats, or hard caps; identification for newly employed, inexperienced...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Distinctively colored hard hats, or hard caps... STANDARDS-UNDERGROUND COAL MINES Miscellaneous § 75.1720-1 Distinctively colored hard hats, or hard caps; identification for newly employed, inexperienced miners. Hard hats or hard caps distinctively different in...

  1. 76 FR 67763 - Notice of Intent To Grant Exclusive License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-02

    ... From the Federal Register Online via the Government Publishing Office NATIONAL AERONAUTICS AND SPACE ADMINISTRATION Notice of Intent To Grant Exclusive License AGENCY: National Aeronautics and Space... of the National Aeronautics and Space Administration. The prospective exclusive license will...

  2. Exclusive-or logic circuit has useful properties

    NASA Technical Reports Server (NTRS)

    Batte, W. G.

    1966-01-01

    Single, simple exclusive-or logic connective eliminates excessive hardware and the number of interconnections between logic modules. This circuit performs the necessary switching for the exclusive-or operation and amplifies, restores, and inverts the signal.

  3. 47 CFR 90.165 - Procedures for mutually exclusive applications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Applications and Authorizations Special Rules Governing Facilities Used to Provide Commercial Mobile Radio Services § 90.165 Procedures for mutually exclusive applications. Mutually exclusive commercial mobile radio service applications are processed...

  4. 27 CFR 6.151 - Exclusion, in general.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Exclusion, in general. 6.151 Section 6.151 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS âTIED-HOUSEâ Exclusion § 6.151 Exclusion, in general. (a) Exclusion, in whole or in part occurs: (1) When a...

  5. Hardness of cubic solid solutions

    PubMed Central

    Gao, Faming

    2017-01-01

    We demonstrate that a hardening rule exists in cubic solid solutions with various combinations of ionic, covalent and metallic bonding. It is revealed that the hardening stress ∆τFcg is determined by three factors: shear modulus G, the volume fraction of solute atoms fv, and the size misfit degree δb. A simple hardening correlation in KCl-KBr solid-solution is proposed as ∆τFcg = 0.27 G. It is applied to calculate the hardening behavior of the Ag-Au, KCl-KBr, InP-GaP, TiN-TiC, HfN-HfC, TiC-NbC and ZrC-NbC solid-solution systems. The composition dependence of hardness is elucidated quantitatively. The BN-BP solid-solution system is quantitatively predicted. We find a hardening plateau region around the x = 0.55–0.85 in BNxP1−x, where BNxP1−x solid solutions are far harder than cubic BN. Because the prediction is quantitative, it sets the stage for a broad range of applications. PMID:28054659

  6. Hardness of cubic solid solutions

    NASA Astrophysics Data System (ADS)

    Gao, Faming

    2017-01-01

    We demonstrate that a hardening rule exists in cubic solid solutions with various combinations of ionic, covalent and metallic bonding. It is revealed that the hardening stress ∆τFcg is determined by three factors: shear modulus G, the volume fraction of solute atoms fv, and the size misfit degree δb. A simple hardening correlation in KCl-KBr solid-solution is proposed as ∆τFcg = 0.27 G. It is applied to calculate the hardening behavior of the Ag-Au, KCl-KBr, InP-GaP, TiN-TiC, HfN-HfC, TiC-NbC and ZrC-NbC solid-solution systems. The composition dependence of hardness is elucidated quantitatively. The BN-BP solid-solution system is quantitatively predicted. We find a hardening plateau region around the x = 0.55–0.85 in BNxP1‑x, where BNxP1‑x solid solutions are far harder than cubic BN. Because the prediction is quantitative, it sets the stage for a broad range of applications.

  7. Hard X-ray delays

    NASA Technical Reports Server (NTRS)

    Schwartz, Richard A.

    1986-01-01

    High time resolution hard X-ray rates with good counting statistics over 5 energy intervals were obtained using a large area balloon-borne scintillation detector during the 27 June 1980 solar flare. The impulsive phase of the flare was comprised of a series of major bursts of several to several tens of seconds long. Superimposed on these longer bursts are numerous smaller approximately 0.5 to 1.0 second spikes. The time profiles for different energies were cross-correlated for the major bursts. The rapid burst decay rates and the simultaneous peaks below 120 keV both indicate a rapid electron energy loss process. Thus, the flux profiles reflect the electron acceleration/injection process. The fast rate data was obtained by a burst memory in 8 and 32 msec resolution over the entire main impulsive phase. These rates will be cross-correlated to look for short time delays and to find rapid fluctuations. However, a cursory examination shows that almost all fluctuations, down to the 5% level, were resolved with 256 msec bins.

  8. 21 CFR 1404.945 - Excluded or exclusion.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Excluded or exclusion. 1404.945 Section 1404.945 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.945 Excluded or exclusion. Excluded or exclusion means— (a) That a person...

  9. 78 FR 23886 - Notice of Intent To Grant Exclusive License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... Agricultural Research Service Notice of Intent To Grant Exclusive License AGENCY: Agricultural Research Service..., Agricultural Research Service, intends to grant to Biosortia Pharmaceuticals of Dublin, Ohio, an exclusive... prospective exclusive license may be granted unless, within thirty (30) days from the date of this...

  10. 20 CFR 416.1218 - Exclusion of the automobile.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ..., BLIND, AND DISABLED Resources and Exclusions § 416.1218 Exclusion of the automobile. (a) Automobile; defined. As used in this section, the term automobile includes, in addition to passenger cars, other... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Exclusion of the automobile. 416.1218...

  11. Why is entry exclusion an essential feature of conjugative plasmids?

    PubMed

    Garcillán-Barcia, M Pilar; de la Cruz, Fernando

    2008-07-01

    Entry exclusion is a property of plasmids by which the cells that contain them become bad recipients in additional conjugation rounds. This work reviews entry exclusion essential features and analyzes the mechanisms of action of the best studied systems. We searched for homologs of the proteins responsible for experimentally known exclusion systems. Results were used to classify exclusion systems in families of related elements. We arrive to the conclusion that all conjugative plasmids contain at least one entry exclusion gene. Although entry exclusion genes seem to be part of the plasmid conjugative machinery, they are systematically absent in phylogenetically related type IV protein exporting machines involved in virulence for plants and animals. We infer from this fact that entry exclusion is an essential feature of conjugative plasmid biology. Mathematical models suggest that plasmids expressing entry exclusion selectively eliminate plasmids lacking it, reinforcing its essential character and suggesting that entry exclusion plays a direct role in plasmid survival. Other experimental results confirm that entry exclusion is essential for the stability of a conjugative plasmid. We suggest that entry exclusion limits the damage of lethal zygosis (bacterial death produced by excessive rounds of conjugation). Additionally, it avoids competition in a host among identical plasmid backbones. Conversely, the lack of entry exclusion in conjugative transposons can be understood as a means of generating rapid evolutionary change.

  12. 46 CFR 16.109 - Public Interest Exclusion (PIE).

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Public Interest Exclusion (PIE). 16.109 Section 16.109... General § 16.109 Public Interest Exclusion (PIE). Service agents are subject to Public Interest Exclusion (PIE) actions in accordance with 49 CFR Part 40, subpart R. The PIE is an action which excludes...

  13. 40 CFR 152.83 - Definition of exclusive use study.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 24 2014-07-01 2014-07-01 false Definition of exclusive use study. 152... Protection of Data Submitters' Rights § 152.83 Definition of exclusive use study. A study is an exclusive use study if it meets the conditions of either paragraph (a) or paragraph (b) of this section. (a)...

  14. 47 CFR 90.165 - Procedures for mutually exclusive applications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... SPECIAL RADIO SERVICES PRIVATE LAND MOBILE RADIO SERVICES Applications and Authorizations Special Rules... exclusive applications. Mutually exclusive commercial mobile radio service applications are processed in... 47 Telecommunication 5 2011-10-01 2011-10-01 false Procedures for mutually exclusive...

  15. 20 CFR 416.1230 - Exclusion of life insurance.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Exclusion of life insurance. 416.1230 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1230 Exclusion of life insurance. (a) General. In determining the resources of an individual (and spouse, if any), life insurance owned by the individual...

  16. 29 CFR 794.121 - Exclusion of excise taxes.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 3 2010-07-01 2010-07-01 false Exclusion of excise taxes. 794.121 Section 794.121 Labor... Exclusion of excise taxes. The computation of the annual gross volume of sales of the enterprise for purposes of section 7(b)(3) is made “exclusive of excise taxes.” It will be noted that the excise...

  17. 20 CFR 416.1230 - Exclusion of life insurance.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Exclusion of life insurance. 416.1230 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1230 Exclusion of life insurance. (a) General. In determining the resources of an individual (and spouse, if any), life insurance owned by the individual...

  18. 20 CFR 416.1230 - Exclusion of life insurance.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Exclusion of life insurance. 416.1230 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1230 Exclusion of life insurance. (a) General. In determining the resources of an individual (and spouse, if any), life insurance owned by the individual...

  19. Social Exclusion and Career Development: A United Kingdom Perspective

    ERIC Educational Resources Information Center

    Watts, A. G.

    2010-01-01

    Social exclusion can be defined in different ways, but a prominent definition--in relation to young people in particular--is exclusion from formal learning and paid employment. This ignores the role of informal learning and the informal economies. In England, career guidance services were remodelled to deal with the issue of social exclusion by…

  20. 77 FR 31399 - Notice of Intent To Grant Exclusive License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-25

    ... SPACE ADMINISTRATION Notice of Intent To Grant Exclusive License AGENCY: National Aeronautics and Space Administration. ACTION: Notice of Intent To Grant Exclusive Research Only License. SUMMARY: This notice is issued... to grant an exclusive, research only license in the United States to practice the invention...

  1. 42 CFR 402.308 - Waivers of exclusions.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... authorization to obtain information from private health insurers, peer review organizations (including, but not... of exclusion request. An excluded person must submit a request for waiver of exclusion in writing to... the submitter that the waiver of exclusion request has been received. (2) Reviews and validates...

  2. 78 FR 27181 - Notice of Intent To Grant Exclusive License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-09

    ... Agricultural Research Service Notice of Intent To Grant Exclusive License AGENCY: Agricultural Research Service..., Agricultural Research Service, intends To grant to AIC Partners Group, LLC of Sylvester, Georgia, an exclusive... conditions of 35 U.S.C. 209 and 37 CFR 404.7. The prospective exclusive license may be granted unless,...

  3. 76 FR 14417 - Prospective Grant of Exclusive License

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-16

    ... HUMAN SERVICES National Institutes of Health Prospective Grant of Exclusive License AGENCY: National Institutes of Health, Public Health Service, HHS. ACTION: Notice of intent to grant exclusive license... grant of an exclusive patent license to intellectual property broker ICAP Ocean Tomo to promote...

  4. Social Judgments and Emotion Attributions about Exclusion in Switzerland

    ERIC Educational Resources Information Center

    Malti, Tina; Killen, Melanie; Gasser, Luciano

    2012-01-01

    Adolescents' social judgments and emotion attributions about exclusion in three contexts, nationality, gender, and personality, were measured in a sample of 12- and 15-year-old Swiss and non-Swiss adolescents (N = 247). Overall, adolescents judged exclusion based on nationality as less acceptable than exclusion based on gender or personality.…

  5. 20 CFR 416.1210 - Exclusions from resources; general.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Exclusions from resources; general. 416.1210... AGED, BLIND, AND DISABLED Resources and Exclusions § 416.1210 Exclusions from resources; general. In determining the resources of an individual (and spouse, if any), the following items shall be excluded:...

  6. 20 CFR 416.1210 - Exclusions from resources; general.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Exclusions from resources; general. 416.1210... AGED, BLIND, AND DISABLED Resources and Exclusions § 416.1210 Exclusions from resources; general. In determining the resources of an individual (and spouse, if any), the following items shall be excluded:...

  7. 20 CFR 416.1210 - Exclusions from resources; general.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Exclusions from resources; general. 416.1210... AGED, BLIND, AND DISABLED Resources and Exclusions § 416.1210 Exclusions from resources; general. In determining the resources of an individual (and spouse, if any), the following items shall be excluded:...

  8. 20 CFR 416.1210 - Exclusions from resources; general.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Exclusions from resources; general. 416.1210... AGED, BLIND, AND DISABLED Resources and Exclusions § 416.1210 Exclusions from resources; general. In determining the resources of an individual (and spouse, if any), the following items shall be excluded:...

  9. 20 CFR 416.1210 - Exclusions from resources; general.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Exclusions from resources; general. 416.1210... AGED, BLIND, AND DISABLED Resources and Exclusions § 416.1210 Exclusions from resources; general. In determining the resources of an individual (and spouse, if any), the following items shall be excluded:...

  10. 33 CFR 2.30 - Exclusive Economic Zone.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 1 2014-07-01 2014-07-01 false Exclusive Economic Zone. 2.30... JURISDICTION Jurisdictional Terms § 2.30 Exclusive Economic Zone. (a) With respect to the United States... States exercises sovereignty, exclusive economic zone means the zone seaward of and adjacent to...

  11. 33 CFR 2.30 - Exclusive Economic Zone.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 1 2013-07-01 2013-07-01 false Exclusive Economic Zone. 2.30... JURISDICTION Jurisdictional Terms § 2.30 Exclusive Economic Zone. (a) With respect to the United States... States exercises sovereignty, exclusive economic zone means the zone seaward of and adjacent to...

  12. 33 CFR 2.30 - Exclusive Economic Zone.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 1 2011-07-01 2011-07-01 false Exclusive Economic Zone. 2.30... JURISDICTION Jurisdictional Terms § 2.30 Exclusive Economic Zone. (a) With respect to the United States... States exercises sovereignty, exclusive economic zone means the zone seaward of and adjacent to...

  13. 33 CFR 2.30 - Exclusive Economic Zone.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 1 2012-07-01 2012-07-01 false Exclusive Economic Zone. 2.30... JURISDICTION Jurisdictional Terms § 2.30 Exclusive Economic Zone. (a) With respect to the United States... States exercises sovereignty, exclusive economic zone means the zone seaward of and adjacent to...

  14. 42 CFR 1003.134 - Effect of exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Effect of exclusion. 1003.134 Section 1003.134 Public Health OFFICE OF INSPECTOR GENERAL-HEALTH CARE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OIG AUTHORITIES CIVIL MONEY PENALTIES, ASSESSMENTS AND EXCLUSIONS § 1003.134 Effect of exclusion. The effect of...

  15. 42 CFR 1002.211 - Effect of exclusion.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Effect of exclusion. 1002.211 Section 1002.211 Public Health OFFICE OF INSPECTOR GENERAL-HEALTH CARE, DEPARTMENT OF HEALTH AND HUMAN SERVICES OIG AUTHORITIES PROGRAM INTEGRITY-STATE-INITIATED EXCLUSIONS FROM MEDICAID Permissive Exclusions § 1002.211...

  16. 21 CFR 1404.945 - Excluded or exclusion.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Excluded or exclusion. 1404.945 Section 1404.945 Food and Drugs OFFICE OF NATIONAL DRUG CONTROL POLICY GOVERNMENTWIDE DEBARMENT AND SUSPENSION (NONPROCUREMENT) Definitions § 1404.945 Excluded or exclusion. Excluded or exclusion means— (a) That a person...

  17. 20 CFR 416.1234 - Exclusion of Indian lands.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Exclusion of Indian lands. 416.1234 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1234 Exclusion of Indian lands. In determining the... tribe, we will exclude any interest of the individual (or spouse, if any) in land which is held in...

  18. 20 CFR 416.1234 - Exclusion of Indian lands.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Exclusion of Indian lands. 416.1234 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1234 Exclusion of Indian lands. In determining the... tribe, we will exclude any interest of the individual (or spouse, if any) in land which is held in...

  19. 20 CFR 416.1234 - Exclusion of Indian lands.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Exclusion of Indian lands. 416.1234 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1234 Exclusion of Indian lands. In determining the... tribe, we will exclude any interest of the individual (or spouse, if any) in land which is held in...

  20. 47 CFR 76.123 - Satellite syndicated program exclusivity.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 4 2013-10-01 2013-10-01 false Satellite syndicated program exclusivity. 76... Exclusivity and Sports Blackout § 76.123 Satellite syndicated program exclusivity. (a) Upon receiving notification pursuant to paragraph (d) of this section, a satellite carrier shall not deliver, to...

  1. 47 CFR 76.123 - Satellite syndicated program exclusivity.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 4 2014-10-01 2014-10-01 false Satellite syndicated program exclusivity. 76... Exclusivity and Sports Blackout § 76.123 Satellite syndicated program exclusivity. (a) Upon receiving notification pursuant to paragraph (d) of this section, a satellite carrier shall not deliver, to...

  2. 20 CFR 416.1218 - Exclusion of the automobile.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Exclusion of the automobile. 416.1218 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1218 Exclusion of the automobile. (a) Automobile; defined. As used in this section, the term automobile includes, in addition to passenger cars,...

  3. 20 CFR 416.1218 - Exclusion of the automobile.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Exclusion of the automobile. 416.1218 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1218 Exclusion of the automobile. (a) Automobile; defined. As used in this section, the term automobile includes, in addition to passenger cars,...

  4. 20 CFR 416.1218 - Exclusion of the automobile.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Exclusion of the automobile. 416.1218 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1218 Exclusion of the automobile. (a) Automobile; defined. As used in this section, the term automobile includes, in addition to passenger cars,...

  5. 20 CFR 416.1218 - Exclusion of the automobile.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Exclusion of the automobile. 416.1218 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1218 Exclusion of the automobile. (a) Automobile; defined. As used in this section, the term automobile includes, in addition to passenger cars,...

  6. 20 CFR 416.1230 - Exclusion of life insurance.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Exclusion of life insurance. 416.1230 Section..., BLIND, AND DISABLED Resources and Exclusions § 416.1230 Exclusion of life insurance. (a) General. In determining the resources of an individual (and spouse, if any), life insurance owned by the individual...

  7. 26 CFR 1.72-4 - Exclusion ratio.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 26 Internal Revenue 2 2013-04-01 2013-04-01 false Exclusion ratio. 1.72-4 Section 1.72-4 Internal... TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.72-4 Exclusion ratio. (a) General rule... annuities described in section 72(o) and § 1.122-1), an exclusion ratio is to be determined for...

  8. 26 CFR 1.72-4 - Exclusion ratio.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 26 Internal Revenue 2 2012-04-01 2012-04-01 false Exclusion ratio. 1.72-4 Section 1.72-4 Internal... TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.72-4 Exclusion ratio. (a) General rule... annuities described in section 72(o) and § 1.122-1), an exclusion ratio is to be determined for...

  9. 26 CFR 1.72-4 - Exclusion ratio.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 2 2010-04-01 2010-04-01 false Exclusion ratio. 1.72-4 Section 1.72-4 Internal... TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.72-4 Exclusion ratio. (a) General rule... annuities described in section 72(o) and § 1.122-1), an exclusion ratio is to be determined for...

  10. 26 CFR 1.72-4 - Exclusion ratio.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 26 Internal Revenue 2 2014-04-01 2014-04-01 false Exclusion ratio. 1.72-4 Section 1.72-4 Internal... TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.72-4 Exclusion ratio. (a) General rule... annuities described in section 72(o) and § 1.122-1), an exclusion ratio is to be determined for...

  11. 26 CFR 1.72-4 - Exclusion ratio.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 26 Internal Revenue 2 2011-04-01 2011-04-01 false Exclusion ratio. 1.72-4 Section 1.72-4 Internal... TAXES (CONTINUED) Items Specifically Included in Gross Income § 1.72-4 Exclusion ratio. (a) General rule... annuities described in section 72(o) and § 1.122-1), an exclusion ratio is to be determined for...

  12. 21 CFR 316.34 - FDA recognition of exclusive approval.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false FDA recognition of exclusive approval. 316.34... (CONTINUED) DRUGS FOR HUMAN USE ORPHAN DRUGS Orphan-drug Exclusive Approval § 316.34 FDA recognition of exclusive approval. (a) FDA will send the sponsor (or, the permanent-resident agent, if applicable)...

  13. New approaches to hard bubble suppression

    NASA Technical Reports Server (NTRS)

    Henry, R. D.; Besser, P. J.; Warren, R. G.; Whitcomb, E. C.

    1973-01-01

    Description of a new double-layer method for the suppression of hard bubbles that is more versatile than previously reported suppression techniques. It is shown that it may be possible to prevent hard bubble generation without recourse to exchange coupling of multilayer films.

  14. Hard Spring Wheat Technical Committee 2016 Crop

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Seven experimental lines of hard spring wheat were grown at up to five locations in 2016 and evaluated for kernel, milling, and bread baking quality against the check variety Glenn. Wheat samples were submitted through the Wheat Quality Council and processed and milled at the USDA-ARS Hard Red Spri...

  15. "Hard Science" for Gifted 1st Graders

    ERIC Educational Resources Information Center

    DeGennaro, April

    2006-01-01

    "Hard Science" is designed to teach 1st grade gifted students accurate and high level science concepts. It is based upon their experience of the world and attempts to build a foundation for continued love and enjoyment of science. "Hard Science" provides field experiences and opportunities for hands-on discovery working beside experts in the field…

  16. Hardness methods for testing maize kernels.

    PubMed

    Fox, Glen; Manley, Marena

    2009-07-08

    Maize is a highly important crop to many countries around the world, through the sale of the maize crop to domestic processors and subsequent production of maize products and also provides a staple food to subsistance farms in undeveloped countries. In many countries, there have been long-term research efforts to develop a suitable hardness method that could assist the maize industry in improving efficiency in processing as well as possibly providing a quality specification for maize growers, which could attract a premium. This paper focuses specifically on hardness and reviews a number of methodologies as well as important biochemical aspects of maize that contribute to maize hardness used internationally. Numerous foods are produced from maize, and hardness has been described as having an impact on food quality. However, the basis of hardness and measurement of hardness are very general and would apply to any use of maize from any country. From the published literature, it would appear that one of the simpler methods used to measure hardness is a grinding step followed by a sieving step, using multiple sieve sizes. This would allow the range in hardness within a sample as well as average particle size and/or coarse/fine ratio to be calculated. Any of these parameters could easily be used as reference values for the development of near-infrared (NIR) spectroscopy calibrations. The development of precise NIR calibrations will provide an excellent tool for breeders, handlers, and processors to deliver specific cultivars in the case of growers and bulk loads in the case of handlers, thereby ensuring the most efficient use of maize by domestic and international processors. This paper also considers previous research describing the biochemical aspects of maize that have been related to maize hardness. Both starch and protein affect hardness, with most research focusing on the storage proteins (zeins). Both the content and composition of the zein fractions affect

  17. Softening the Blow of Social Exclusion: The Responsive Theory of Social Exclusion.

    PubMed

    Freedman, Gili; Williams, Kipling D; Beer, Jennifer S

    2016-01-01

    Social exclusion is an interactive process between multiple people, yet previous research has focused almost solely on the negative impacts on targets. What advice is there for people on the other side (i.e., sources) who want to minimize its negative impact and preserve their own reputation? To provide an impetus for research on the interactive nature of exclusion, we propose the Responsive Theory of Social Exclusion. Our theory postulates that targets and sources' needs are better maintained if sources use clear, explicit verbal communication. We propose that sources have three options: explicit rejection (clearly stating no), ostracism (ignoring), and ambiguous rejection (being unclear). Drawing on psychology, sociology, communications, and business research, we propose that when sources use explicit rejection, targets' feelings will be less hurt, their needs will be better protected, and sources will experience less backlash and emotional toil than if sources use ambiguous rejection or ostracism. Finally, we propose how the language of rejections may impact both parties.

  18. Death to perturbative QCD in exclusive processes?

    SciTech Connect

    Eckardt, R.; Hansper, J.; Gari, M.F.

    1994-04-01

    The authors discuss the question of whether perturbative QCD is applicable in calculations of exclusive processes at available momentum transfers. They show that the currently used method of determining hadronic quark distribution amplitudes from QCD sum rules yields wave functions which are completely undetermined because the polynomial expansion diverges. Because of the indeterminacy of the wave functions no statement can be made at present as to whether perturbative QCD is valid. The authors emphasize the necessity of a rigorous discussion of the subject and the importance of experimental data in the range of interest.

  19. Central exclusive production at the Tevatron

    NASA Astrophysics Data System (ADS)

    Albrow, Michael

    2014-11-01

    The Collider Detector at Fermilab, CDF, observed for the first time in hadron-hadron collisions photon-photon (γ + γ → e+e-, μ+μ-) and photon-pomeron (γ + ℙ → J/ψ, ψ(2S)) interactions, as well as p+\\bar {p}-> p+χc+\\bar {p} by double pomeron exchange, ℙ + ℙ or DPE. Exclusive π+π- production was also measured at √ {s} = 900 GeV and 1960 GeV; resonance structures are discussed.

  20. Exclusive lower extremity mirror movements and diastematomyelia.

    PubMed

    Tubbs, R Shane; Smyth, Matthew D; Dure, Leon S; Oakes, W Jerry

    2004-01-01

    Mirror movements usually seen in the Klippel-Feil syndrome are most commonly appreciated in the upper extremities. Lower extremity involvement is seen rarely and when observed, is found in conjunction with upper extremity mirror movements. We report what we believe to be the first case of mirror movements found exclusively in the lower extremities in a female patient presenting with tethered cord syndrome. Our hopes are that this report will help elucidate mechanisms involved with these anomalous movements, as currently there is no commonly accepted etiology.

  1. Hardness Evolution of Gamma-Irradiated Polyoxymethylene

    NASA Astrophysics Data System (ADS)

    Hung, Chuan-Hao; Harmon, Julie P.; Lee, Sanboh

    2016-12-01

    This study focuses on analyzing hardness evolution in gamma-irradiated polyoxymethylene (POM) exposed to elevated temperatures after irradiation. Hardness increases with increasing annealing temperature and time, but decreases with increasing gamma ray dose. Hardness changes are attributed to defects generated in the microstructure and molecular structure. Gamma irradiation causes a decrease in the glass transition temperature, melting point, and extent of crystallinity. The kinetics of defects resulting in hardness changes follow a first-order structure relaxation. The rate constant adheres to an Arrhenius equation, and the corresponding activation energy decreases with increasing dose due to chain scission during gamma irradiation. The structure relaxation of POM has a lower energy barrier in crystalline regions than in amorphous ones. The hardness evolution in POM is an endothermic process due to the semi-crystalline nature of this polymer.

  2. Thermal spray coatings replace hard chrome

    SciTech Connect

    Schroeder, M.; Unger, R.

    1997-08-01

    Hard chrome plating provides good wear and erosion resistance, as well as good corrosion protection and fine surface finishes. Until a few years ago, it could also be applied at a reasonable cost. However, because of the many environmental and financial sanctions that have been imposed on the process over the past several years, cost has been on a consistent upward trend, and is projected to continue to escalate. Therefore, it is very important to find a coating or a process that offers the same characteristics as hard chrome plating, but without the consequent risks. This article lists the benefits and limitations of hard chrome plating, and describes the performance of two thermal spray coatings (tungsten carbide and chromium carbide) that compared favorably with hard chrome plating in a series of tests. It also lists three criteria to determine whether plasma spray or hard chrome plating should be selected.

  3. Social Exclusion/Inclusion: Foucault's Analytics of Exclusion, the Political Ecology of Social Inclusion and the Legitimation of Inclusive Education

    ERIC Educational Resources Information Center

    Peters, Michael A.; Besley, Tina A. C.

    2014-01-01

    This article offers a broad philosophical and historical background to the dyad of social exclusion/inclusion by examining the analytics and politics of exclusion first by reference to Michel Foucault who studies the modern history of exclusion and makes it central to his approach in understanding the development of modern institutions of emerging…

  4. Action co-representation and social exclusion.

    PubMed

    Costantini, Marcello; Ferri, Francesca

    2013-05-01

    Humans are thought to be able to form shared representations, considered a keystone of social cognition. However, whether and to what extent such representations are social in nature is still open for debate. In the present study, we address the question of whether action co-representation can be modulated by social attitudes, such as judgments about one's own social status. Two groups of participants performed an Interactive Simon task after the experimental induction of a feeling of social inclusion or exclusion (ostracism) by means of a virtual ball tossing game. Results showed a compatibility effect in included, but not in excluded participants. This indicates that judgments about one's own social status modulate action co-representation. We suggest that this modulation may occur by way of a redirection of one's attentional focus away from others when one experiences social exclusion. This is a far-reaching issue given the increasing need for integration in modern society. Indeed, if integration fails, modern society fails also.

  5. Hoarding Symptoms Are Not Exclusive to Hoarders

    PubMed Central

    Novara, Caterina; Bottesi, Gioia; Dorz, Stella; Sanavio, Ezio

    2016-01-01

    Hoarding disorder (HD) was originally conceptualized as a subcategory of obsessive compulsive disorder (OCD), and numerous studies have in fact focused exclusively on investigating the comorbidity between OCD and HD. Hoarding behavior can nevertheless also be found in other clinical populations and in particular in patients with eating disorders (ED), anxiety disorders (AD), major depression (MD), and psychotic disorders (PD). The current study was carried out with the aim of investigating, using a validated instrument such as the Saving Inventory-Revised (SI-R), the presence of HD symptoms in patients diagnosed with ED, AD, MD, and PD. Hoarding symptomatology was also assessed in groups of self-identified hoarders and healthy controls. The results revealed that 22.5% of the ED patients exceeded the cut-off for the diagnosis of HD, followed by 7.7% of the patients with MD, 7.4% of the patients with AD, and 5.9% of the patients with PD. The patients with ED had significantly higher SI-R scores than the other groups in the Acquisition and Difficulty Discarding scales while the AD, MD, and PD patients were characterized exclusively by Difficulty Discarding. These data suggest to clinicians that hoarding symptoms should be assessed in other types of patients and especially in those affected by Bulimia and Binge eating. PMID:27891104

  6. Exclusion of Nitrate from Frozen Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Marrocco, H. A.; Michelsen, R. R.

    2013-12-01

    Reactions occurring at the surface of ice, sea ice, and snow in Earth's cryosphere have an impact on the composition of the overlying atmosphere. In order to elucidate reaction mechanisms and model their contributions to atmospheric processes, the morphology of frozen aqueous surfaces and amounts of reactants contained therein must be determined. To this end, the exclusion of nitrate ions to the surface of frozen aqueous solutions has been studied by attenuated total reflection infrared spectroscopy (ATR-IR). In this technique the near-surface region of the frozen films are interrogated to a depth of a few hundred nanometers from the film-crystal interface. Aqueous solutions (0.001 to 0.01 M) of sodium nitrate (NaNO3), magnesium nitrate (Mg(NO3)2), and nitric acid (HNO3) were quickly frozen on the germanium ATR crystal and observed at a constant temperature of about -18°C. In addition to ice and the solutes, liquid water in varying amounts was observed in the spectra. The amount of nitrate in the surface liquid is three to four orders of magnitude higher than in the unfrozen solution. While all the nitrate salts exhibit exclusion to the unfrozen surface, the dynamics are different for different counter-ions. Results are compared to freezing point depression data and the predictions of equilibrium thermodynamics.

  7. Cluster analysis of historical and modern hard red spring wheat cultivars based on parentage and HPLC analysis of gluten forming proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, 30 hard red spring (HRS) wheat cultivars released between 1910 and 2013 were analyzed to determine how they cluster in terms of parentage and protein data, analyzed by reverse-phase HPLC (RP-HPLC) of gliadins, and size-exclusion HPLC (SE-HPLC) of unreduced proteins. Dwarfing genes in...

  8. Does Walking Mitigate Affective and Cognitive Responses to Social Exclusion?

    PubMed

    Paoli, Anthony G Delli; Smith, Alan L; Pontifex, Matthew B

    2017-03-02

    Social exclusion can produce harmful affective and cognitive responses that undermine healthy functioning. Physical activity is known to have acute affective and cognitive effects that are adaptive, and therefore may mitigate these responses. The purpose of this study was to assess walking as a strategy to reduce the effects of social exclusion on affect and working memory performance. Healthy female college students (N = 96, M(age) = 19.2 ± 0.8 years) were randomly assigned to one of four experimental conditions: (a) sedentary plus neutral feedback, (b) sedentary plus exclusion feedback, (c) walking plus neutral feedback, or (d) walking plus exclusion feedback. Pre and post activity and pre and post feedback measures of affect and working memory performance were recorded. Excluded participants had a significant negative shift in affect following feedback, p < .05. Those who were sedentary prior to exclusion had lower affect scores following exclusion than the walking plus exclusion and the neutral feedback groups, p < .05. There were no direct effects of walking or social exclusion on working memory. However, perceptions of being ignored predicted smaller improvements in working memory performance for participants who were sedentary prior to exclusion, p < .05. The findings suggest that walking prior to social exclusion may mitigate the affective response to social exclusion as well as social perceptions that can undermine working memory. More broadly, this work supports continued examination of physical activity as a potential strategy for helping individuals cope with negative social experiences.

  9. Exclusion and Marginalisation in Adolescence: The Experience of School Exclusion on Drug Use and Antisocial Behaviour

    ERIC Educational Resources Information Center

    McCrystal, Patrick; Percy, Andrew; Higgins, Kathryn

    2007-01-01

    Young people excluded from school are a group at an increased risk of drug use and antisocial behaviour during adolescence and later marginalisation and exclusion from society in adulthood. As part of the Belfast Youth Development Study, a longitudinal study of the onset and development of adolescent drug use, young people who entered post-primary…

  10. Evaluation of exclusion prenatal and exclusion preimplantation genetic diagnosis for Huntington's disease in the Netherlands.

    PubMed

    van Rij, M C; de Die-Smulders, C E M; Bijlsma, E K; de Wert, G M W R; Geraedts, J P; Roos, R A C; Tibben, A

    2013-02-01

    Individuals at 50% risk of Huntington's disease (HD) who prefer not to know their carrier status, might opt for exclusion prenatal diagnosis (ePND) or exclusion preimplantation genetic diagnosis (ePGD). This study aims to provide a better understanding of couples' motives for choosing ePND or ePND, and surveys couples' experiences in order to make recommendations for the improvement of counselling for exclusion testing. This qualitative retrospective interview study focussed on couples who underwent ePND or ePGD for HD in the period 1996-2010. Seventeen couples were included of which 13 had experienced ePND and 6 ePGD. Mean time-interval since exclusion-testing was 3.9 years. Couples' moral reservations regarding termination of pregnancy (TOP) or discarding healthy embryos were counterbalanced by the wish to protect their future child against HD. Seven couples had terminated a total of 11 pregnancies with a 50% HD risk, none showed regret. ePGD was used by couples who wanted to avoid (another) TOP. ePND and ePGD are acceptable reproductive options for a specific group of counsellees. To guarantee sound standards of care, it is imperative that candidate couples be given in-depth non-directive counselling about all possible scenarios, and adequate professional and psychological support prior to, during and after ePND/ePGD.

  11. Analysis of Hard Thin Film Coating

    NASA Technical Reports Server (NTRS)

    Shen, Dashen

    1998-01-01

    MSFC is interested in developing hard thin film coating for bearings. The wearing of the bearing is an important problem for space flight engine. Hard thin film coating can drastically improve the surface of the bearing and improve the wear-endurance of the bearing. However, many fundamental problems in surface physics, plasma deposition, etc, need further research. The approach is using electron cyclotron resonance chemical vapor deposition (ECRCVD) to deposit hard thin film an stainless steel bearing. The thin films in consideration include SiC, SiN and other materials. An ECRCVD deposition system is being assembled at MSFC.

  12. Analysis of Hard Thin Film Coating

    NASA Technical Reports Server (NTRS)

    Shen, Dashen

    1998-01-01

    Marshall Space Flight Center (MSFC) is interested in developing hard thin film coating for bearings. The wearing of the bearing is an important problem for space flight engine. Hard thin film coating can drastically improve the surface of the bearing and improve the wear-endurance of the bearing. However, many fundamental problems in surface physics, plasma deposition, etc, need further research. The approach is using Electron Cyclotron Resonance Chemical Vapor Deposition (ECRCVD) to deposit hard thin film on stainless steel bearing. The thin films in consideration include SiC, SiN and other materials. An ECRCVD deposition system is being assembled at MSFC.

  13. Exclusive photoproduction of the cascade (Xi) hyperon

    SciTech Connect

    John Price; Bernard Nefkens; Justin Ducote; John Goetz; et. Al.

    2004-09-01

    We report on the first measurement of exclusive {Xi}{sup -}(1321) hyperon photoproduction in {gamma}p {yields} K{sup +}K{sup +}{Xi}{sup -} for 3.2 < E{sub {gamma}} < 3.9 GeV. The final state is identified by the missing mass in p({gamma}, K{sup +}K{sup +})X measured with the CLAS detector at Jefferson Laboratory. We have detected a significant number of the ground-state {Xi}{sup -}(132)1/2{sup +}, and have estimated the total cross section for its production. We have also observed the first excited state {Xi}{sup -}(1530)3/2{sup +}. Photoproduction provides a copious source of {Xi}'s. We discuss the possibilities of a search for the recently proposed {Xi}{sub 5}{sup --} and {Xi}{sub 5}{sup +} pentaquarks.

  14. Novel phases in an accelerated exclusion process

    NASA Astrophysics Data System (ADS)

    Dong, Jiajia; Klumpp, Stefan; Zia, Royce K. P.

    2013-03-01

    We introduce a class of distance-dependent interactions in an accelerated exclusion process (AEP) inspired by the cooperative speed-up observed in transcribing RNA polymerases. In the simplest scenario, each particle hops to the neighboring site if vacant and when joining a cluster of particles, triggers the frontmost particle to hop. Through both simulation and theoretical work, we discover that the steady state of AEP displays a discontinuous transition with periodic boundary condition. The system transitions from being homogeneous (with augmented currents) to phase-segregated. More surprisingly, the current-density relation in the phase-segregated state is simply J = 1 - ρ , indicating the particles (or holes) are moving at unit velocity despite the inclusion of long-range interactions. US NSF DMR- 1104820 and DMR-1005417

  15. {lambda}0 Polarization in Exclusive pp Reactions

    SciTech Connect

    Felix, J.

    2006-09-25

    Among all properties of baryons, the polarization they acquire when created from unpolarized p-nucleus collisions is the most recent discovered one; so far, the origin of this polarization remains unexplained in spite of the experimental evidences accumulated in the past thirty years. Up to these days, {lambda}0 is the most studied baryon for polarization, due to it is very easy to produce {lambda}0's at the energies of the principal high energy physics accelerators of the world. This article is a review of the experimental experience accumulated on the polarization of {lambda}0 in unpolarized exclusive pp collisions as function of xF, PT, and M({lambda}0K+) in the past fifteen years here at the Instituto de Fisica, Universidad de Guanajuato, inside Fermilab e690 and Brookhaven National Laboratory e766 collaborations.

  16. Exclusive photoproduction of the cascade ({xi}) hyperons

    SciTech Connect

    Price, J.W.; Nefkens, B.M.K.; Ducote, J.L.; Goetz, J.T.; Adams, G.; Cummings, J.P.; Empl, A.; Frolov, V.; Hu, J.; Klusman, M.; Kubarovsky, V.; Li Ji; Napolitano, J.; Stoler, P.; Ungaro, M.; Witkowski, M.; Ambrozewicz, P.; Kramer, L.H.; Nasseripour, R.; Raue, B.A.

    2005-05-01

    We report on the first measurement of exclusive {xi}{sup -}(1321) hyperon photoproduction in {gamma}p{yields}K{sup +}K{sup +}{xi}{sup -} for 3.2

  17. Gompertz law and aging as exclusion effects.

    PubMed

    Hallén, Anund

    2007-10-01

    The exponential increase with age in mortality rate, the Gompertz law, indicates that the decrease in vitality and viability linked to aging depends on phenomena with exponential or logarithmic dynamics. Gompertz slope (alpha) is assumed to be a measure of aging rate, provided the studied cohort is homogeneous and in a supporting environment. The law provides no clue about the cause of aging, but may be formally correlated with various physical or mathematical functions. A possible correlation between the Ogston-Laurent exclusion equation and human aging is examined. An increase with age of an inert cross-linked insoluble protein network is assumed to result in a logarithmic decrease in water volume available to colloidal macromolecules. In this model, alpha is assumed to be a measure of the rate of accumulation of the polypeptide network.

  18. Concurrent behavior: Are the interpretations mutually exclusive?

    PubMed Central

    Lyon, David O.

    1982-01-01

    The experimental literature is replete with examples of behavior which occur concurrently with a schedule of reinforcement. These concurrent behaviors, often with similar topographies and occurring under like circumstances, may be interpreted as functionally autonomous, collateral, adjunctive, superstitious or mediating behavior. The degree to which the interaction of concurrent and schedule controlled behavior is used in the interpretation of behavior illustrated the importance of distinguishing among these interpretations by experimental procedure. The present paper reviews the characteristics of these interpretations, and discusses the experimental procedures necessary to distinguish among them. The paper concludes that the interpretations are mutually exclusive and refer to distinct behaviors, but that the distinction between any two of the interpretations requires more than one experimental procedure. PMID:22478568

  19. Synchronized shocks in an inhomogeneous exclusion process

    NASA Astrophysics Data System (ADS)

    Arita, Chikashi

    2015-11-01

    We study an exclusion process with 4 segments, which was recently introduced by T. Banerjee, N. Sarkar and A. Basu (J. Stat. Mech. (2015) P01024). The segments have hopping rates 1, r(<1) , 1 and r, respectively. In a certain parameter region, two shocks appear, which are not static but synchronized. We explore dynamical properties of each shock and correlation of shocks, by means of the so-called second-class particle. The mean-squared displacement of shocks has three diffusive regimes, and the asymptotic diffusion coefficient is different from the known formula. In some time interval, it also exhibits sub-diffusion, being proportional to t1/2 . Furthermore we introduce a correlation function and a crossover time, in order to quantitatively characterize the synchronization. We numerically estimate the dynamical exponent for the crossover time. We also revisit the 2-segment case and the open boundary condition for comparison.

  20. Propagating Resource Constraints Using Mutual Exclusion Reasoning

    NASA Technical Reports Server (NTRS)

    Frank, Jeremy; Sanchez, Romeo; Do, Minh B.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    One of the most recent techniques for propagating resource constraints in Constraint Based scheduling is Energy Constraint. This technique focuses in precedence based scheduling, where precedence relations are taken into account rather than the absolute position of activities. Although, this particular technique proved to be efficient on discrete unary resources, it provides only loose bounds for jobs using discrete multi-capacity resources. In this paper we show how mutual exclusion reasoning can be used to propagate time bounds for activities using discrete resources. We show that our technique based on critical path analysis and mutex reasoning is just as effective on unary resources, and also shows that it is more effective on multi-capacity resources, through both examples and empirical study.