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27 results on '"nucleon: spin"'

1. Measurement of the proton spin structure at long distances

Author

P. Eugenio, J. Brock, N. Dashyan, I. Bedlinskiy, S. Choi, P. Nadel-Turonski, A. Hobart, M. Defurne, S. E. Kuhn, Latifa Elouadrhiri, P. Chatagnon, M. Ripani, C. D. Keith, D. Bulumulla, Aditya R. Khanal, S. Adhikari, B. McKinnon, T. Holmstrom, V. Mokeev, G. V. Fedotov, H. S. Jo, L. Guo, Alessandro Rizzo, Andrea Bianconi, L. Barion, M. Mirazita, K. Livingston, M. Hattawy, N. Markov, G. Rosner, Simon Širca, S. Fegan, Y. Ghandilyan, Jie Zhang, P. Bosted, Michael Paolone, C. Carlin, M. Guidal, M. L. Seely, E. Pasyuk, D. P. Watts, F. Bossu, Laura Clark, S. Niccolai, N. Guler, M. Holtrop, B. Yale, R. A. Schumacher, P. Rossi, W. Phelps, V. Mascagna, S. Joosten, Axel Schmidt, Alexandre Deur, Luciano Pappalardo, Nikolaos Sparveris, V. Crede, I. I. Strakovsky, W. Kim, Fatiha Benmokhtar, M. Ehrhart, D. I. Glazier, V. P. Kubarovsky, T. A. Forest, O. Pogorelko, Z. W. Zhao, J. Rowley, S. Stepanyan, A. I. Ostrovidov, K. Park, Krishna Neupane, R. De Vita, A. El Alaoui, Y. Ilieva, Nicholas Zachariou, D. G. Ireland, C. W. Kim, H. Avakian, C. Mullen, W. K. Brooks, A. Kripko, Andrea Celentano, Volker D. Burkert, A. S. Biselli, J. C. Carvajal, V. Sulkosky, H. Atac, Karl Slifer, M. Leali, F. Sabatié, L. Venturelli, Y. G. Sharabian, X. Zheng, M. Bondì, H. Voskanyan, P. Lenisa, W. J. Briscoe, I. J. D. MacGregor, M. Contalbrigo, S. K. Phillips, T. Mineeva, T. B. Hayward, Friedrich Klein, Brian Raue, J. Poudel, N. Tyler, C. Djalali, G. Ciullo, M. Osipenko, Y. Prok, D. S. Carman, X. Wei, K. A. Griffioen, E. Voutier, Dustin Keller, S. Strauch, L. Lanza, R. W. Gothe, Michael Wood, T. Chetry, K. Hafidi, R. Dupre, M. Battaglieri, Gerard Gilfoyle, E. L. Isupov, V. A. Drozdov, S. Boiarinov, H. Kang, U. Shrestha, F.-X. Girod, K. P. Adhikari, H. Hakobyan, J. Ritman, S. Diehl, C. Salgado, R. G. Fersch, M. Ungaro, E. Long, J. P. Chen, D. Heddle, P. L. Cole, D. G. Meekins, A. D'Angelo, K. Hicks, L. El Fassi, K. Joo, M. Khandaker, M. J. Amaryan, A. Filippi, K. L. Giovanetti, Larry Weinstein, L. Marsicano, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
polarizabilities, Photon, Proton, High Energy Physics::Lattice, Nuclear Theory, General Physics and Astronomy, polarized target, polarized beam, 01 natural sciences, 7. Clean energy, 010305 fluids & plasmas, High Energy Physics - Experiment, Theoretical Nuclear Physics, Experimental Nuclear Physics, High Energy Physics - Experiment (hep-ex), effective field theory, Economica, Proton spin crisis, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Experimental particle Physics, order, Nuclear Experiment (nucl-ex), Nuclear Experiment, Spin-½, Quantum chromodynamics, Physics, Settore FIS/04, nucleon, virtual compton-scattering, chiral perturbation-theory, sum-rule, moments, evolution, sum rule, kinematics, Quantum electrodynamics, nuclear matter, Nucleon, nucleon: structure, Strong interaction, FOS: Physical sciences, Socio-culturale, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], p: spin, PE2_2, momentum transfer: low, PE2_1, CLAS, 0103 physical sciences, quantum chromodynamics, ddc:530, 010306 general physics, PE2_3, quark gluon, Coupling constant, nuclear force, scattering, Ambientale, Physics::Accelerator Physics, nucleon: spin, High Energy Physics::Experiment, experimental results
Abstract

Measuring the spin structure of protons and neutrons tests our understanding of how they arise from quarks and gluons, the fundamental building blocks of nuclear matter. At long distances the coupling constant of the strong interaction becomes large, requiring non-perturbative methods to calculate quantum chromodynamics processes, such as lattice gauge theory or effective field theories. Here we report proton spin structure measurements from scattering a polarized electron beam off polarized protons. The spin-dependent cross-sections were measured at large distances, corresponding to the region of low momentum transfer squared between 0.012 and 1.0 GeV$^2$. This kinematic range provides unique tests of chiral effective field theory predictions. Our results show that a complete description of the nucleon spin remains elusive, and call for further theoretical works, e.g. in lattice quantum chromodynamics. Finally, our data extrapolated to the photon point agree with the Gerasimov-Drell-Hearn sum rule, a fundamental prediction of quantum field theory that relates the anomalous magnetic moment of the proton to its integrated spin-dependent cross-sections., Published version. 10 pages, 5 figures. 20 pages of supplementary material (data tables and a figure)

Published
2021
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2. On the canonical formulation of gauge field theories and Poincaré transformations

Author

Daniel N. Blaschke, Francois Gieres, Institut de Physique des 2 Infinis de Lyon (IP2I Lyon), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)

Subjects
High Energy Physics - Theory, Poisson bracket, Nuclear Theory, High Energy Physics::Lattice, energy-momentum, rotation, 01 natural sciences, Hamiltonian formalism: classical, Quantization (physics), High Energy Physics - Phenomenology (hep-ph), Poincare, radiation: gauge, quantization: canonical, invariance: gauge, Gauge theory, Becchi-Rouet-Stora, Mathematical physics, Physics, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], 16. Peace & justice, High Energy Physics - Phenomenology, space-time, kinematics, covariance, symbols, Hamiltonian (quantum mechanics), Lorentz, Nuclear and High Energy Physics, Angular momentum, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Canonical quantization, Lorentz transformation, gauge field theory: translation, FOS: Physical sciences, angular momentum, Nuclear Theory (nucl-th), p: spin, symbols.namesake, electromagnetic field, 0103 physical sciences, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, 010306 general physics, 010308 nuclear & particles physics, gluon, BRST quantization, High Energy Physics - Theory (hep-th), [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], lcsh:QC770-798, nucleon: spin, path integral
Abstract

We address the Hamiltonian formulation of classical gauge field theories while putting forward results some of which are not entirely new, though they do not appear to be well known. We refer in particular to the fact that neither the canonical energy momentum vector $(P^\mu )$ nor the gauge invariant energy momentum vector $(P_{\textrm{inv}} ^\mu )$ do generate space-time translations of the gauge field by means of the Poisson brackets: In a general gauge, one has to consider the so-called kinematical energy momentum vector and, in a specific gauge (like the radiation gauge in electrodynamics), one has to consider the Dirac brackets rather than the Poisson brackets. Similar arguments apply to rotations and to Lorentz boosts and are of direct relevance to the "nucleon spin crisis" since the spin of the proton involves a contribution which is due to the angular momentum vector of gluons and thereby requires a proper treatment of the latter. We conclude with some comments on the relationships between the different approaches to quantization (canonical quantization based on the classical Hamiltonian formulation, Gupta-Bleuler, path integrals, BRST, covariant canonical approaches)., Comment: 43 pages; Version accepted for publication in Nucl. Phys. B. Includes the interpretation of results on Hamiltonian symmetry generators as well as a concise and unified derivation of the gauge invariant currents associated to conformal invariance

Published
2021
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3. Timelike Compton Scattering with CLAS12 at Jefferson Lab

Author

Pierre Chatagnon, Institut de Physique Nucléaire d'Orsay (IPNO), Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11), and CLAS

Subjects
Quark, History, Particle physics, Angular momentum, angular distribution: asymmetry, generalized parton distribution, Nuclear Theory, Parton, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], angular momentum, 01 natural sciences, Education, Momentum, deeply virtual Compton scattering, 0103 physical sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], quark: helicity, Nuclear Experiment, 010306 general physics, Spin-½, Physics, longitudinal momentum, higher-order: 0, quark: flavor, 010308 nuclear & particles physics, Compton scattering, Helicity, Computer Science Applications, transverse, correlation, nucleon: spin, High Energy Physics::Experiment, Nucleon, talk, Jefferson Lab
Abstract

International audience; Generalized Parton Distributions (GPDs) describe the correlations between the longitudinal momentum and the transverse position of the partons inside the nucleon. At leading order, four quark helicity conserving GPDs per quark flavor describe the nucleon structure. For their direct relation to the angular momentum contribution of partons to the spin of the nucleon and to the pressure distribution in the nucleon, GPDs have been at the center of many experimental programs. GPDs have been studied mainly using Deeply Virtual Compton Scattering (DVCS). Here we highlight the measurement of the time-reversal conjugate process of DVCS, Timelike Compton Scattering (TCS), using data taken by CLAS12. The experimental measurement of the TCS angular asymmetry will provide new information on the real part of GPDs.This proceeding assesses the current status of the TCS analysis andpresents preliminary results based on CLAS12 data.

Published
2020
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4. Measurement of P T -weighted Sivers asymmetries in leptoproduction of hadrons

Author

Alexeev, M.G., Alexeev, G.D., Amoroso, A., Andrieux, V., Anfimov, N.V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Azevedo, C.D.R., Badełek, B., Balestra, F., Ball, M., Barth, J., Barone, V., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E.R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Büchele, M., Burtsev, V.E., Chang, W.-C., Chatterjee, C., Chiosso, M., Chumakov, A.G., Chung, S.-U., Cicuttin, A., Crespo, M.L., Dalla Torre, S., Dasgupta, S.S., Dasgupta, S., Denisov, O.Yu., Dhara, L., Donskov, S.V., Doshita, N., Dreisbach, Ch., Dünnweber, W., Dusaev, R.R., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P.D., Faessler, M., Ferrero, A., Finger, M., Finger, Michael, Jr., Fischer, H., Franco, C., du Fresne von Hohenesche, N., Friedrich, J.M., Frolov, V., Gautheron, F., Gavrichtchouk, O.P., Gerassimov, S., Giarra, J., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Grosse Perdekamp, M., Grube, B., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C.-Y., Huber, S., Ishimoto, S., Ivanov, A., Iwata, T., Jandek, M., Jary, V., Joosten, R., Jörg, P., Juraskova, K., Kabuß, E., Kaspar, F., Kerbizi, A., Ketzer, B., Khaustov, G.V., Khokhlov, Yu.A., Kisselev, Yu., Klein, F., Koivuniemi, J.H., Kolosov, V.N., Kondo, K., Konorov, I., Konstantinov, V.F., Kotzinian, A.M., Kouznetsov, O.M., Kral, Z., Krämer, M., Krinner, F., Kroumchtein, Z.V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R.P., Kveton, A., Lednev, A.A., Levorato, S., Lian, Y.-S., Lichtenstadt, J., Longo, R., Lyubovitskij, V.E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G.K., Mamon, S.A., Marianski, B., Martin, A., Marzec, J., Matoušek, J., Matsuda, T., Meshcheryakov, G.V., Meyer, M., Meyer, W., Mikhailov, Yu.V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Neyret, D., Nový, J., Nowak, W.-D., Nukazuka, G., Nunes, A.S., Olshevsky, A.G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J.-C., Pereira, F., Pešek, M., Pešková, M., Peshekhonov, D.V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V.A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Ryabchikov, D.I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V.D., Sandacz, A., Sarkar, S., Savin, I.A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmieden, H., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B.I., Vauth, A., Veit, B.M., Veloso, J., Vidon, A., Virius, M., Wagner, M., Wallner, S., Wilfert, M., Zaremba, K., Zavada, P., Zavertyaev, M., Zhao, Y., Zemlyanichkina, E., Ziembicki, M., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Azevedo, C. D. R., Badełek, B., Balestra, F., Ball, M., Barth, J., Barone, V., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Büchele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Dalla Torre, S., Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Dünnweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Elia, C., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Fischer, H., Franco, C., du Fresne von Hohenesche, N., Friedrich, J. M., Frolov, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Grosse Perdekamp, M., Grube, B., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heitz, R., Herrmann, F., Horikawa, N., D'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Iwata, T., Jandek, M., Jary, V., Joosten, R., Jörg, P., Juraskova, K., Kabuß, E., Kaspar, F., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Krämer, M., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kveton, A., Lednev, A. A., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matoušek, J., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Neyret, D., Nový, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pešek, M., Pešková, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmieden, H., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Sozzi, F., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veit, B. M., Veloso, J., Vidon, A., Virius, M., Wagner, M., Wallner, S., Wilfert, M., Zaremba, K., Zavada, P., Zavertyaev, M., Zhao, Y., Zemlyanichkina, E., Ziembicki, M., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and COMPASS

Subjects
Nuclear and High Energy Physics, Nuclear Theory, FOS: Physical sciences, hadron: transverse momentum, COMPASS, fragmentation function, High Energy Physics - Experiment, hadron: leptoproduction, p: target, Sivers function, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], polarization: transverse, Nuclear Experiment, spin: transverse, Particle Physics - Phenomenology, hep-ex, hep-ph, distribution function: transverse momentum dependence, semi-inclusive reaction, High Energy Physics - Phenomenology, spin: asymmetry: measured, nucleon: spin, High Energy Physics::Experiment, quark: polarization, Particle Physics - Experiment
Abstract

The transverse spin asymmetries measured in semi-inclusive leptoproduction of hadrons, when weighted with the hadron transverse momentum $P_T$, allow for the extraction of important transverse-momentum-dependent distribution functions. In particular, the weighted Sivers asymmetries provide direct information on the Sivers function, which is a leading-twist distribution that arises from a correlation between the transverse momentum of an unpolarised quark in a transversely polarised nucleon and the spin of the nucleon. Using the high-statistics data collected by the COMPASS Collaboration in 2010 with a transversely polarised proton target, we have evaluated two types of $P_T$-weighted Sivers asymmetries, which are both proportional to the product of the firsttransverse moment of the Sivers function and of the fragmentation function. The results are compared to the standard unweighted Sivers asymmetries and used to extract the first transverse moments of the Sivers distributions for $u$ and $d$ quarks., Comment: 23 pages, 12 figures

Published
2019
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5. Longitudinal spin structure of the nucleon at COMPASS

Author

Yann Bedfer, Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and COMPASS

Subjects
Quark, Physics, Particle physics, quark: sea, deep inelastic scattering: semi-inclusive reaction, sum rule: Bjorken, gluon, Spin structure, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], deep inelastic scattering: inclusive reaction, COMPASS, Gluon, quark: spin, structure function: longitudinal, Compass, Quark–gluon plasma, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Physics - Experiment, High Energy Physics::Experiment, nucleon: spin, Sum rule in quantum mechanics, muon nucleon: scattering, Nucleon, Particle Physics - Experiment, Spin-½
Abstract

International audience; For a large fraction of its already twenty year long existence, the COMPASS collaboration hasstudied the polarised structure of the nucleon via muon-nucleon scattering. This paper summa-rizes the final results obtained in longitudinally polarised DIS, either inclusive or semi-inclusive.For inclusive DIS, these cover the measurements of structure function $g_1$, and the information ex-tracted from them in terms of polarised PDFs (pPDFs) and Bjorken sum rule. From $g_1$ measure-ments alone, combining COMPASS with world data, the quark spin contribution to the nucleonspin is determined to be 0.26 < ∆Σ < 0.36. And from COMPASS data alone, the Bjorken sumrule is verified to 9% accuracy. In semi-inclusive DIS, more information can be gained on the pPDFs of sea quarks and gluons. A selection of our achievements along this line are reported.

Published
2018
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6. A Fixed-Target Programme at the LHC: Physics Case and Projected Performances for Heavy-Ion, Hadron, Spin and Astroparticle Studies

Author

Laure Marie Massacrier, C. Hadjidakis, A. Zelenski, D. P. Kikola, J. Seixas, E.G. Ferreiro, Jakub Wagner, Zishuo Yang, Nataliya Topilskaya, W. Scandale, A. Klein, S. Porteboeuf Houssais, Cédric Lorcé, Patrick Robbe, Jean-Philippe Lansberg, Antonio Uras, C. L. Da Silva, Andrea Signori, Barbara Antonina Trzeciak, Miguel G. Echevarria, I. Hřivnáčová, G. Cavoto, F. Donato, Hua-Sheng Shao, Florian Lyonnet, Stanley J. Brodsky, Nodoka Yamanaka, A. B. Kurepin, C. Quintans, Ingo Schienbein, A. Rakotozafindrabe, A. Kusina, Y. I. Makdisi, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique Subatomique et de Cosmologie (LPSC), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Institut Polytechnique de Grenoble - Grenoble Institute of Technology-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA), Laboratoire de Physique Théorique et Hautes Energies (LPTHE), Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), Laboratoire Leprince-Ringuet (LLR), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Centre de Physique Théorique [Palaiseau] (CPHT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique de Clermont (LPC), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Clermont Auvergne (UCA)-Centre National de la Recherche Scientifique (CNRS), Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Laboratoire de l'Accélérateur Linéaire (LAL), Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique des 2 Infinis Irène Joliot-Curie (IJCLab), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP ), Université Grenoble Alpes (UGA), Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
heavy ion: scattering, Nuclear Theory, Physics::Instrumentation and Detectors, p nucleus: interaction, Hadron, heavy-ion physics, General Physics and Astronomy, parton: distribution function, beam transport, nucl-ex, hadron structure, fixed-target program for the Large Hadron Collider, 01 natural sciences, COMPASS, High Energy Physics - Experiment, Sivers function, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), ALICE, Compass, target: wire, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], Nuclear Experiment (nucl-ex), Nuclear Experiment, bent crystal, gas: polarized target, Spin-½, Physics, Large Hadron Collider, Detector, hep-ph, collective phenomena, hadronization, nuclear physics, TMD physics, spin physics, astrophysics, Proton (rocket family), High Energy Physics - Phenomenology, CERN LHC Coll, Nuclear Physics - Theory, proposed experiment, Particle Physics - Experiment, performance, astroparticles, p p: scattering, nucl-th, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], energy loss, FOS: Physical sciences, Context (language use), [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], gluon: polarization, Nuclear Theory (nucl-th), Nuclear physics, 0103 physical sciences, Nuclear Physics - Experiment, heavy ion physics, 010306 general physics, Particle Physics - Phenomenology, hep-ex, 010308 nuclear & particles physics, transverse momentum: dependence, nuclear matter: effect, nucleon: structure function, LHC-B, Beamline, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], Physics::Accelerator Physics, nucleon: spin, ion, quarkonium: hadroproduction, quark: polarization
Abstract

We review the context, the motivations and the expected performances of a comprehensive and ambitious fixed-target program using the multi-TeV proton and ion LHC beams. We also provide a detailed account of the different possible technical implementations ranging from an internal wire target to a full dedicated beam line extracted with a bent crystal. The possibilities offered by the use of the ALICE and LHCb detectors in the fixed-target mode are also reviewed., LaTeX, 115 pages. v2: version submitted to Physics Reports. A few figures added and some text improved. v3: accepted for publication in Physics Reports

Published
2018
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7. Longitudinal double-spin asymmetry $A_1^{\rm p}$ and spin-dependent structure function $g_1^{\rm p}$ of the proton at small values of $x$ and $Q^2$

Author

Aghasyan, M., Akhunzyanov, R., Alexeev, M. G., Alexeev, G. D., Amoroso, A., Andrieux, V., Anfimov, N. V., Anosov, V., Antoshkin, A., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C. D. R., Badelek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Bressan, A., Buechele, M., Burtsev, V. E., Chang, W. -C., Chatterjee, C., Chiosso, M., Choi, I., Chumakov, A. G., Chung, S. -U., Cicuttin, A., Crespo, M. L., Torre, S. Dalla, Dasgupta, S. S., Dasgupta, S., Denisov, O. Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duennweber, W., Dusaev, R. R., Dziewiecki, M., Efremov, A., Eversheim, P. D., Faessler, M., Ferrero, A., Finger, M., Fischer, H., Franco, C., von Hohenesche, N. du Fresne, Friedrich, J. M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grasso, A., Gridin, A., Perdekamp, M. Grosse, Grube, B., Grussenmeyer, T., Guskov, A., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C. -Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Joerg, P., Kabuss, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Koivuniemi, J. H., Kolosov, V. N., Kondo, K., Koenigsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Kral, Z., Kraemer, M., Kremser, P., Krinner, F., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Kuznetsov, I. I., Kveton, A., Lednev, A. A., Levchenko, E. A., Levillain, M., Levorato, S., Lian, Y. -S., Lichtenstadt, J., Longo, R., Lyubovitskij, V. E., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G. K., Mamon, S. A., Marianski, B., Martin, A., Marzec, J., Matousek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Moretti, A., Nagaytsev, A., Nerling, F., Neyret, D., Novy, J., Nowak, W. -D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J. -C., Pereira, F., Pesek, M., Peskova, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V. A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Rogacheva, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schoenning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Tasevsky, M., Tessaro, S., Tessarotto, F., Thiel, A., Tomsa, J., Tosello, F., Tskhay, V., Uhl, S., Vasilishin, B. I., Vauth, A., Veloso, J., Vidon, A., Virius, M., Wallner, S., Weisrock, T., Wilfert, M., ter Wolbeek, J., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay, Laboratoire AIM, Université Paris Diderot - Paris 7 ( UPD7 ) -Centre d'Etudes de Saclay, COMPASS, Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), and Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112))

Subjects
small-x, CERN Lab, [formula omitted], FOS: Physical sciences, sum rule: Bjorken, structure function: spin, spin: dependence, COMPASS, beam: energy, High Energy Physics - Experiment, x-dependence, High Energy Physics - Experiment (hep-ex), p: spin, momentum transfer: low, [ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex], [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], p: structure function, Nuclear Experiment, A1, hep-ex, muon: beam, spin: effect, photon, Inelastic muon scattering, CERN SPS, Low [formula omitted], Low Q2, Low x, Spin structure function, g1, muon p: deep inelastic scattering, Physics::Accelerator Physics, High Energy Physics::Experiment, nucleon: spin, muon: polarized beam, spin: longitudinal, statistical, spin: asymmetry, Particle Physics - Experiment, experimental results
Abstract

We present a precise measurement of the proton longitudinal double-spin asymmetry $A_1^{\rm p}$ and the proton spin-dependent structure function $g_1^{\rm p}$ at photon virtualities $0.006~({\rm GeV}/c)^2, Comment: 19 pages, 7 figures

Published
2018
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8. The relativistic center of mass in field theory with spin

Author

Cédric Lorcé, Centre de Physique Théorique [Palaiseau] (CPHT), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Centre de Physique Théorique [Palaiseau] ( CPHT ), and École polytechnique ( X ) -Centre National de la Recherche Scientifique ( CNRS )

Subjects
High Energy Physics - Theory, Angular momentum, Physics and Astronomy (miscellaneous), Observer (quantum physics), FOS: Physical sciences, parton: distribution function, Parton, lcsh:Astrophysics, plane wave, field theory, angular momentum, 01 natural sciences, [ PHYS.HTHE ] Physics [physics]/High Energy Physics - Theory [hep-th], Theoretical physics, High Energy Physics - Phenomenology (hep-ph), 13.88.+e, 0103 physical sciences, lcsh:QB460-466, lcsh:Nuclear and particle physics. Atomic energy. Radioactivity, 010306 general physics, Engineering (miscellaneous), spin: transverse, Physics, light front, 010308 nuclear & particles physics, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], quantum mechanics: relativistic, High Energy Physics - Phenomenology, Transverse plane, Formalism (philosophy of mathematics), High Energy Physics - Theory (hep-th), quantum mechanics: effect, tensor: energy-momentum, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], lcsh:QC770-798, [ PHYS.HPHE ] Physics [physics]/High Energy Physics - Phenomenology [hep-ph], nucleon: spin, 11.30.Cp, Nucleon, spin: longitudinal
Abstract

In order to unravel the origin of the nucleon spin, one has to study in detail the question of orbital angular momentum, and in particular the reference point about which it is defined. With this in mind, we review the concept of relativistic center of mass, generalize the discussion to the case of asymmetric energy-momentum tensors, and establish the link with the light-front formalism. We find that the $p$-wave in the Dirac plane-wave solutions arises from a relativistic quantum-mechanical effect which forces the canonical reference point to depend on the observer. This explains why longitudinal spin is much simpler to study than transverse spin. It is also the reason behind the observation of induced shifts and distortions in the parton distributions defined within the light-front formalism., Comment: 41 pages, 1 figure, version accepted in EPJC

Published
2018
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9. Deeply Virtual Compton Scattering at 11GeV in Jefferson Lab Hall A

Author

Frédéric Georges, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Jefferson Lab Hall A, and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
Angular momentum, Particle physics, generalized parton distribution, electron p: inelastic scattering, electron: polarized beam, interference, parton: distribution function, Parton, Nucleon spin structure, polarized beam, Bethe-Heitler, Momentum, p: target, talk: Salamanca 2017/09/25, deeply virtual Compton scattering, 11 GeV, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], electron: beam, Nuclear Experiment, parton: momentum spectrum, Physics, quark: angular momentum, Momentum transfer, Compton scattering, nucleon: structure function, sum rule, sum rule: spin, total cross section: measured, kinematics, accelerator: upgrade, nucleon: spin, High Energy Physics::Experiment, Sum rule in quantum mechanics, Nucleon, momentum transfer: high, experimental results, Jefferson Lab
Abstract

International audience; Introduced in the mid 90's, Generalized Parton Distributions (GPDs) are now a key element in the study of the nucleon internal structure. Indeed, GPDs encapsulate both spatial and momentum distributions of partons inside a nucleon. Through the Ji sum rule, they also allow to derive the total orbital angular momentum of quarks, which is a crucial point to unravel the nucleon spin structure.GPDs are experimentally accessible through Deeply Virtual Compton Scattering (DVCS) and its interference with the Bethe-Heitler process at high momentum transfer $Q^{2}$. A worldwide experimental program was started in the early 2000's to extract these GPDs. The subject of this document, a DVCS $ep \rightarrow e'p'\gamma$ experiment performed at Jefferson Laboratory, Hall A (Virginia, USA) between 2014 and 2016, is encompassed in this program.The aim of this experiment is to extract with high precision the DVCS helicity-dependent cross sections as a function of the momentum transfer $Q^{2}$, for fixed values of the Bjorken variable $x_{Bj}$, on a proton target. The recent upgrade of the accelerator facility to 12 GeV allows to cover a larger $Q^{2}$ lever arm than for previous measurements and probe yet unexplored kinematic regions, while the polarized electron beam will allow the separation of the contributions from the real and imaginary parts of the DVCS amplitude to the total cross section.This document will give an overview of the ongoing data analysis for this experiment, followed by the presentation of the obtained preliminary results.

Published
2017
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10. Longitudinal spin structure of the nucleon: COMPASS legacy

Author

Yann Bedfer, Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, and COMPASS

Subjects
Physics, History, Particle physics, [PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], 010308 nuclear & particles physics, polarization: longitudinal, sum rule: Bjorken, Spin structure, [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], gluon: polarization, 01 natural sciences, COMPASS, Computer Science Applications, Education, quark: spin, structure function: polarization, semi-inclusive reaction, Compass, 0103 physical sciences, High Energy Physics::Experiment, nucleon: spin, 010306 general physics, Nucleon, charge: axial
Abstract

International audience; The COMPASS collaboration has dedicated a large fraction of its already twenty year long existence to the study of the polarised structure of the nucleon. This presentation addresses two of the investigated aspects: inclusive measurements and direct measurements of the gluon polarised PDF, Δg. In the first case, a summary of what constitutes COMPASS legacy is presented. This covers the actual measurements of structure function g 1, at both high and low Q 2, and the information extracted from them in terms of polarised PDFs, axial charge and Bjorken sum rule. In particular, the quark spin contribution to the nucleon spin is determined to be 0.26 < Δ∑ < 0.36 and from COMPASS data alone the Bjorken sum rule is verified to 9% accuracy. In the second case, the latest developments in the analysis of our data on semi-inclusive single-hadron production at high-pT are reported.

Published
2017
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11. Spin-dependent $\mu \to e$ conversion

Author

Cirigliano, Vincenzo, Davidson, Sacha, Kuno, Yoshitaka, Institut de Physique Nucléaire de Lyon (IPNL), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique Nucléaire de Lyon ( IPNL ), Université Claude Bernard Lyon 1 ( UCBL ), Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS ( IN2P3 ) -Centre National de la Recherche Scientifique ( CNRS ), Centre National de la Recherche Scientifique (CNRS)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)

Subjects
operator: vector, new physics, effective Lagrangian, lepton: flavor: violation, operator: axial-vector, operator: dipole, spin: dependence, High Energy Physics - Phenomenology, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], recoil: effect, operator: flavor changing, [ PHYS.HPHE ] Physics [physics]/High Energy Physics - Phenomenology [hep-ph], nucleon: spin, four-fermion interaction, numerical calculations
Abstract

The experimental sensitivity to $\mu \to e$ conversion on nuclei is expected to improve by four orders of magnitude in coming years. We consider the impact of $\mu \to e$ flavour-changing tensor and axial-vector four-fermion operators which couple to the spin of nucleons. Such operators, which have not previously been considered, contribute to $\mu \to e$ conversion in three ways: in nuclei with spin they mediate a spin-dependent transition; in all nuclei they contribute to the coherent ($A^2$-enhanced) spin-independent conversion via finite recoil effects and via loop mixing with dipole, scalar, and vector operators. We estimate the spin-dependent rate in Aluminium (the target of the upcoming COMET and Mu2e experiments), show that the loop effects give the greatest sensitivity to tensor and axial-vector operators involving first-generation quarks, and discuss the complementarity of the spin-dependent and independent contributions to $\mu \to e$ conversion, Comment: 6 pages, I figure, typo corrected in eqn 6

Published
2017
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12. Final COMPASS results on the deuteron spin-dependent structure function gd1 and the Bjorken sum rule

Author

Adolph, C., Aghasyan, M., Augustyniak, W., Kolosov, V. N., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V. F., Kotzinian, A. M., Kouznetsov, O. M., Krämer, M., Kremser, P., Krinner, F., Austregesilo, A., Kroumchtein, Z. V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R. P., Lednev, A. A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y.-S., Azevedo, C. D. R., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, Gerhard K., Marianski, B., Martin, A., Marzec, J., Badelek, B., Matoušek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G. V., Meyer, M., Meyer, W., Mikhailov, Yu. V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Balestra, F., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Nový, J., Nowak, W.-D., Nukazuka, G., Nunes, A. S., Olshevsky, A. G., Orlov, I., Ball, M., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J.-C., Pereira, F., Pešek, M., Peshekhonov, D. V., Pierre, N., Platchkov, S., Barth, J., Pochodzalla, J., Polyakov, V. A., Pretz, Jörg, Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Beck, R., Rossiyskaya, N. S., Ryabchikov, D. I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V. D., Sandacz, A., Santos, C., Sarkar, S., Savin, I. A., Bedfer, Y., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schönning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Bernhard, J., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Akhunzyanov, R., Bicker, K., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Bielert, E. R., Uhl, S., Vauth, A., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, Malte Christian, Windmolders, R., Wolbeek, J. ter, Birsa, R., Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., Zink, A., COMPASS Collaboration, Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Büchele, M., Chang, W.-C., Alexeev, M. G., Chatterjee, C., Chiosso, M., Choi, I., Chung, S.-U., Cicuttin, A., Crespo, M. L., Curiel, Q., Dalla Torre, S., Dasgupta, S. S., Dasgupta, S., Alexeev, G. D., Denisov, Oleg Yu., Dhara, L., Donskov, S. V., Doshita, N., Dreisbach, Ch., Duic, V., Dünnweber, W., Dziewiecki, M., Efremov, A., Eversheim, P. D., Amoroso, A., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Fischer, H., Franco, C., du Fresne von Hohenesche, N., Friedrich, J. M., Frolov, V., Fuchey, E., Andrieux, V., Gautheron, F., Gavrichtchouk, O. P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmüller, S., Grasso, A., Grosse-Perdekamp, M., Anfimov, N. V., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F. H., Heitz, R., Herrmann, F., Anosov, V., Horikawa, N., d'Hose, N., Hsieh, C.-Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Augsten, K., Jörg, P., Kabuß, E., Kerbizi, A., Ketzer, B., Khaustov, G. V., Khokhlov, Yu. A., Kisselev, Yu., Klein, F., Klimaszewski, K., and Koivuniemi, J. H.

Subjects
perturbation theory [quantum chromodynamics], deep inelastic scattering [muon deuteron], cross section: ratio, sum rule: Bjorken, polarized target, muon deuteron: deep inelastic scattering, structure function: spin, momentum transfer dependence, COMPASS, energy [beam], beam: energy, scaling: Bjorken, hadronic [final state], renormalization, x-dependence, p: spin, polarization: asymmetry, axial [charge], helicity [quark], strong coupling, quark: helicity, ddc:530, quantum chromodynamics: perturbation theory, charge: axial, Bjorken [sum rule], structure function [deuteron], deuteron: structure function, coupling constant, CERN SPS, spin [p], Bjorken [scaling], kinematics, final state: hadronic, asymmetry [polarization], nucleon: spin, spin [nucleon], muon: polarized beam, ratio [cross section], spin [structure function], polarized beam [muon], statistical, experimental results
Abstract

Physics letters / B 769, 34-41 (2017). doi:10.1016/j.physletb.2017.03.018, Published by North-Holland Publ., Amsterdam

Published
2017
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13. Nucleon Spin and Momentum Decomposition Using Lattice QCD Simulations

Author

Martha Constantinou, Giannis Koutsou, Constantia Alexandrou, A. Vaquero Avilés-Casco, Christian Wiese, Christos Kallidonis, Karl Jansen, and Kyriakos Hadjiyiannakou

Subjects
Nuclear Theory, High Energy Physics::Lattice, General Physics and Astronomy, momentum [gluon], 01 natural sciences, High Energy Physics - Experiment, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), ddc:550, Nuclear Experiment (nucl-ex), Nuclear Experiment, quark: mass dependence, Physics, Quantum chromodynamics, High Energy Physics - Lattice (hep-lat), lattice field theory, Computer Science::Computation and Language (Computational Linguistics and Natural Language and Speech Processing), Lattice QCD, mass dependence [quark], High Energy Physics - Phenomenology, current: axial-vector, valence [quark], quark: valence, Nucleon, quark: Wilson, 3 [n-point function], sea [quark], Particle physics, clover [fermion], Lattice field theory, FOS: Physical sciences, Wilson [quark], fermion: clover, Nuclear Theory (nucl-th), Pion, High Energy Physics - Lattice, Total angular momentum quantum number, quark: flavor: 2, 0103 physical sciences, quantum chromodynamics, flavor: 2 [quark], 010306 general physics, Minimal subtraction scheme, numerical calculations, quark: sea, mass: twist [quark], 010308 nuclear & particles physics, Computer Science::Information Retrieval, High Energy Physics::Phenomenology, Gluon, quark: mass: twist, axial-vector [current], current: vector, vector [current], High Energy Physics::Experiment, nucleon: spin, n-point function: 3, spin [nucleon], gluon: momentum
Abstract

Physical review letters 119(14), 142002 (2017). doi:10.1103/PhysRevLett.119.142002, We determine within lattice QCD the nucleon spin carried by valence and sea quarks and gluons.The calculation is performed using an ensemble of gauge configurations with two degenerate light quarks with mass fixed to approximately reproduce the physical pion mass.We find that the total angular momentum carried by the quarks in the nucleon is $J_{u+d+s}$ = 0.408(61)$_{stat}$(48)$_{syst}$ and the gluon contribution is $J_g$ = 0.133(11)$_{stat}$(14)$_{syst}$, giving a total of $J_N$ = 0.54(6)$_{stat}$(5)$_{syst}$ that is consistent with the spin sum. For the quark intrinsic spin contribution, we obtain $\frac 1{2} \Delta \Sigma _{u+d+s}$ 0.201(17)$_{stat}$(5)$_{syst}$. All quantities are given in the modified minimal subtraction scheme at 2 GeV. The quark and gluon momentum fractions are also computed and add up to $\langle x \rangle_{u+d+s} + \langle x \rangle _g = 0.804(121)_{stat}(95)_{syst} + 0.267(12)_{stat}(10)_{syst} = 1.07(12)_{stat}(10)_{syst}$ hxiuþdþs þ hxig ¼ 0.804ð121Þstatð95Þsyst þ 0.267ð12Þstatð10Þsyst ¼ 1.07ð12Þstatð10Þsyst, thussatisfying the momentum sum., Published by APS, College Park, Md.

Published
2017
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14. Experimental Studies of Hadron Structure via Generalized Parton Distributions

Author

Silvia Niccolai, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and CLAS

Subjects
Physics, Quark, Particle physics, hadron: structure function, generalized parton distribution, Hadron, High Energy Physics::Phenomenology, Degrees of freedom (statistics), Structure (category theory), Compton scattering, parton: distribution function, Parton, nucleon: structure function, Newport News CEBAF Linac, Nuclear physics, talk: Adelaide 2016/09/11, deeply virtual Compton scattering, nuclear physics, CLAS, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], High Energy Physics::Experiment, nucleon: spin, Nuclear Experiment, experimental results, Jefferson Lab
Abstract

International audience; Generalized Parton Distributions (GPDs) provide a unified description of hadronic structure in terms of quark and gluonic degrees of freedom. Deeply virtual Compton scattering (DVCS) is the key reaction to gain information on GPDs. In this article recent results of DVCS from Jefferson Lab, as well as those planned for the near future, are presented and discussed.

Published
2016
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15. Final COMPASS results on the deuteron spin-dependent structure function $g_1^{\rm d}$ and the Bjorken sum rule

Author

Adolph, C., Aghasyan, M., Akhunzyanov, R., Alexeev, M.G., Alexeev, G.D., Amoroso, A., Andrieux, V., Anfimov, N.V., Anosov, V., Augsten, K., Augustyniak, W., Austregesilo, A., Azevedo, C.D.R., Badełek, B., Balestra, F., Ball, M., Barth, J., Beck, R., Bedfer, Y., Bernhard, J., Bicker, K., Bielert, E. R., Birsa, R., Bodlak, M., Bordalo, P., Bradamante, F., Braun, C., Bressan, A., Büchele, M., Chang, W.-C., Chatterjee, C., Chiosso, M., Choi, I., Chung, S.-U., Cicuttin, A., Crespo, M.L., Curiel, Q., Dalla Torre, S., Dasgupta, S.S., Dasgupta, S., Denisov, O.Yu., Dhara, L., Donskov, S.V., Doshita, N., Dreisbach, Ch., Duic, V., Dünnweber, W., Dziewiecki, M., Efremov, A., Eversheim, P.D., Eyrich, W., Faessler, M., Ferrero, A., Finger, M., Finger Jr., M., Fischer, H., Franco, C., du Fresne von Hohenesche, N., Friedrich, J.M., Frolov, V., Fuchey, E., Gautheron, F., Gavrichtchouk, O.P., Gerassimov, S., Giarra, J., Giordano, F., Gnesi, I., Gorzellik, M., Grabmüller, S., Grasso, A., Grosse Perdekamp, M., Grube, B., Grussenmeyer, T., Guskov, A., Haas, F., Hahne, D., Hamar, G., von Harrach, D., Heinsius, F.H., Heitz, R., Herrmann, F., Horikawa, N., d'Hose, N., Hsieh, C.-Y., Huber, S., Ishimoto, S., Ivanov, A., Ivanshin, Yu., Iwata, T., Jary, V., Joosten, R., Jörg, P., Kabuß, E., Kerbizi, A., Ketzer, B., Khaustov, G.V., Khokhlov, Yu.A., Kisselev, Yu., Klein, F., Klimaszewski, K., Koivuniemi, J.H., Kolosov, V.N., Kondo, K., Königsmann, K., Konorov, I., Konstantinov, V.F., Kotzinian, A.M., Kouznetsov, O.M., Krämer, M., Kremser, P., Krinner, F., Kroumchtein, Z.V., Kulinich, Y., Kunne, F., Kurek, K., Kurjata, R.P., Lednev, A.A., Lehmann, A., Levillain, M., Levorato, S., Lian, Y.-S., Lichtenstadt, J., Longo, R., Maggiora, A., Magnon, A., Makins, N., Makke, N., Mallot, G.K., Marianski, B., Martin, A., Marzec, J., Matoušek, J., Matsuda, H., Matsuda, T., Meshcheryakov, G.V., Meyer, M., Meyer, W., Mikhailov, Yu.V., Mikhasenko, M., Mitrofanov, E., Mitrofanov, N., Miyachi, Y., Nagaytsev, A., Nerling, F., Neyret, D., Nový, J., Nowak, W.-D., Nukazuka, G., Nunes, A.S., Olshevsky, A.G., Orlov, I., Ostrick, M., Panzieri, D., Parsamyan, B., Paul, S., Peng, J.-C., Pereira, F., Pešek, M., Peshekhonov, D.V., Pierre, N., Platchkov, S., Pochodzalla, J., Polyakov, V.A., Pretz, J., Quaresma, M., Quintans, C., Ramos, S., Regali, C., Reicherz, G., Riedl, C., Roskot, M., Rossiyskaya, N.S., Ryabchikov, D.I., Rybnikov, A., Rychter, A., Salac, R., Samoylenko, V.D., Sandacz, A., Santos, C., Sarkar, S., Savin, I.A., Sawada, T., Sbrizzai, G., Schiavon, P., Schmidt, K., Schmieden, H., Schönning, K., Seder, E., Selyunin, A., Silva, L., Sinha, L., Sirtl, S., Slunecka, M., Smolik, J., Srnka, A., Steffen, D., Stolarski, M., Subrt, O., Sulc, M., Suzuki, H., Szabelski, A., Szameitat, T., Sznajder, P., Takekawa, S., Tasevsky, M., Tessaro, S., Tessarotto, F., Thibaud, F., Thiel, A., Tosello, F., Tskhay, V., Uhl, S., Vauth, A., Veloso, J., Virius, M., Vondra, J., Wallner, S., Weisrock, T., Wilfert, M., Windmolders, R., Wolbeek, J. ter, Zaremba, K., Zavada, P., Zavertyaev, M., Zemlyanichkina, E., Zhuravlev, N., Ziembicki, M., Zink, A., Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, COMPASS, Institut de Recherches sur les lois Fondamentales de l'Univers ( IRFU ), and Commissariat à l'énergie atomique et aux énergies alternatives ( CEA ) -Université Paris-Saclay

Subjects
cross section: ratio, sum rule: Bjorken, polarized target, FOS: Physical sciences, muon deuteron: deep inelastic scattering, structure function: spin, momentum transfer dependence, COMPASS, beam: energy, High Energy Physics - Experiment, x-dependence, renormalization, scaling: Bjorken, p: spin, High Energy Physics - Experiment (hep-ex), polarization: asymmetry, Spin, [ PHYS.HEXP ] Physics [physics]/High Energy Physics - Experiment [hep-ex], strong coupling, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], quark: helicity, quantum chromodynamics: perturbation theory, Nuclear Experiment, charge: axial, Parton helicity distributions, hep-ex, High Energy Physics::Phenomenology, coupling constant, deuteron: structure function, CERN SPS, Structure function, kinematics, final state: hadronic, nucleon: spin, High Energy Physics::Experiment, muon: polarized beam, statistical, Particle Physics - Experiment, Deep inelastic scattering, experimental results
Abstract

Final results are presented from the inclusive measurement of deep-inelastic polarised-muon scattering on longitudinally polarised deuterons using a $^6$LiD target. The data were taken at $160~{\rm GeV}$ beam energy and the results are shown for the kinematic range $1~({\rm GeV}/c)^2 < Q^2 < 100~({\rm GeV}/c)^2$ in photon virtuality, $0.004 4~{\rm GeV}/c^2$ in the mass of the hadronic final state. The deuteron double-spin asymmetry $A_1^{\rm d}$ and the deuteron longitudinal-spin structure function $g_1^{\rm d}$ are presented in bins of $x$ and $Q^2$. Towards lowest accessible values of $x$, $g_1^{\rm d}$ decreases and becomes consistent with zero within uncertainties. The presented final $g_1^{\rm d}$ values together with the recently published final $g_1^{\rm p}$ values of COMPASS are used to again evaluate the Bjorken sum rule and perform the QCD fit to the $g_1$ world data at next-to-leading order of the strong coupling constant. In both cases, changes in central values of the resulting numbers are well within statistical uncertainties. The flavour-singlet axial charge $a_0$, {which is identified in the $\overline{\rm MS}$ renormalisation scheme with the total contribution of quark helicities to the nucleon spin}, is extracted from only the COMPASS deuteron data with negligible extrapolation uncertainty: $a_0 (Q^2 = 3~({\rm GeV}/c)^2) = 0.32 \pm 0.02_{\rm stat} \pm0.04_{\rm syst} \pm 0.05_{\rm evol}$. Together with the recent results on the proton spin structure function $g_1^{\rm p}$, the results on $g_1^{\rm d}$ constitute the COMPASS legacy on the measurements of $g_1$ through inclusive spin-dependent deep inelastic scattering., Comment: 16 pages, 6 figures

Published
2016
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16. Experimental overview of Deeply Virtual Compton Scattering

Author

Nicole d’Hose, S. Niccolai, Armine Rostomyan, Département de Physique Nucléaire (ex SPhN) (DPHN), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Institut de Physique Nucléaire d'Orsay (IPNO), Université Paris-Sud - Paris 11 (UP11)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Centre National de la Recherche Scientifique (CNRS), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
generalized parton distribution, Hadron, parton: distribution function, Parton, momentum transfer dependence, 01 natural sciences, [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], asymmetry [charge], Nuclear Experiment, colliding beams [electron p], helicity: amplitude analysis, Physics, Compton scattering: form factor, colliding beams [positron p], electron p: colliding beams, asymmetry [angular distribution], off-shell [Compton scattering], Compton scattering: off-shell, distribution function [parton], Nucleon, interference: Bethe-Heitler, Nuclear and High Energy Physics, Particle physics, angular distribution: asymmetry, amplitude analysis [helicity], review, asymmetry [helicity], [PHYS.NEXP]Physics [physics]/Nuclear Experiment [nucl-ex], structure function [nucleon], energy dependence, Nuclear physics, differential cross section: momentum transfer, deeply virtual Compton scattering, 0103 physical sciences, Nuclear fusion, ddc:530, Bethe-Heitler [interference], momentum transfer [differential cross section], 010306 general physics, 010308 nuclear & particles physics, Compton scattering, helicity: asymmetry, nucleon: structure function, positron p: colliding beams, charge: asymmetry, Key (cryptography), nucleon: spin, High Energy Physics::Experiment, spin [nucleon], form factor [Compton scattering], experimental results
Abstract

The European physical journal / A 52(6), 151 (2016). doi:10.1140/epja/i2016-16151-9, Deeply Virtual Compton Scattering (DVCS) is a key reaction to gain information on Generalized Parton Distributions. In this paper the existing measurements of DVCS on the nucleon, as well as those planned for the near future, are presented and discussed., Published by Springer, Berlin

Published
2016
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17. DVCS at HERMES: The recoil detector & transverse target spin asymmetries

Author

Murray, Morgan J.

Subjects
electron p: deep inelastic scattering, generalized parton distribution, Physics::Instrumentation and Detectors, HERMES [magnetic spectrometer], polarized beam, deeply virtual Compton scattering, deep inelastic scattering [positron p], Nuclear Experiment, angular momentum [quark], magnetic spectrometer: HERMES, positron p: deep inelastic scattering, 27.6 GeV, polarized target: transverse, quark: angular momentum, transverse [polarized target], thesis, parametrization, photon: electroproduction, DESY HERA Stor, deep inelastic scattering [electron p], High Energy Physics::Experiment, nucleon: spin, electroproduction [photon], spin [nucleon], asymmetry [spin], spin: asymmetry, detector: recoil, recoil [detector], experimental results
Abstract

University of Glasgow, Diss., 2007; 129 pp., (2007). doi:10.3204/DESY-THESIS-2008-006, The HERMES experiment is a large forward angle spectrometer located at the HERA accelerator ring at DESY, Hamburg. One of the most exciting topics studied at HERMES is Deeply Virtual Compton Scattering (DVCS) which is the simplest interaction that provides a gateway for access to Generalised Parton Distributions (GPDs). GPDs are a theoretical framework which can be used to calculate the total angular momentum of the quarks in the nucleon. As such, they provide one piece of the puzzle of nucleonic spin structure. In 2005, HERMES was upgraded in the target region with a Recoil Detector that allows it to make truly exclusive measurements of the DVCS interaction for the rst time. The design and construction of the Recoil Detector is discussed herein, in addition to a complete analysis of the Transverse Target Spin Asymmetry (TTSA) in DVCS. Experimental facilities that enable measurement of this asymmetry are rare. The importance of the information on the TTSA from HERMES is made yet greater as the transversely polarised target that allows the asymmetry to be measured has been replaced by an unpolarised target. This was to allow the Recoil Detector to be installed. The nal stage of this thesis shows a model-dependent method for constraining the angular momentum of the quarks in the nucleon and speculates as to the other pieces of the spin puzzle., Published by Deutsches Elektronen-Synchrotron, DESY, Hamburg

Published
2007
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18. Polarized Parton Distributions Measured at the HERMES Experiment

Author

Jürgen Wendland

Subjects
HERMES experiment, momentum spectrum [quark], Proton, deep inelastic scattering [positron deuteron], High Energy Physics::Lattice, Nuclear Theory, sum rule: Bjorken, HERMES, Parton, electroproduction [hadron], 27.5 GeV, deep inelastic scattering [positron p], Nuclear Experiment, asymmetry [cross section], Spin-½, Physics, Bjorken [sum rule], positron p: deep inelastic scattering, thesis, cross section: polarization, quark: momentum spectrum, valence [quark], quark: valence, polarization [cross section], polarized target: internal, Nucleon, positron: polarized beam, internal [polarized target], Quark, sea [quark], Particle physics, polarization: longitudinal, hadron: electroproduction, structure function [nucleon], dependence: flavor, Nuclear physics, Pion, statistical analysis, tables, cross section: asymmetry, quark: sea, longitudinal [polarization], flavor [dependence], bibliography, polarization [quark], nucleon: structure function, Deep inelastic scattering, moment, positron deuteron: deep inelastic scattering, nucleon: spin, High Energy Physics::Experiment, polarized beam [positron], spin [nucleon], quark: polarization, experimental results
Abstract

Simon Fraser University, Diss., 2003; 219 pp., (2003). doi:10.3204/DESY-THESIS-2003-032, Published by Deutsches Elektronen-Synchrotron, DESY, Hamburg

Published
2004
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19. GENERALIZED PARTON DISTRIBUTIONS

Author

Markus Diehl

Subjects
hadron: structure function, generalized parton distribution, Hadron, diffraction, General Physics and Astronomy, higher-twist [effect], momentum transfer [expansion], Parton, 02 engineering and technology, Spin structure, 01 natural sciences, energy-momentum [tensor], Interpretation (model theory), High Energy Physics - Phenomenology (hep-ph), strong interaction: coupling constant, parton [angular momentum], Angular momentum coupling, 0202 electrical engineering, electronic engineering, information engineering, electron p: exclusive reaction, impact parameter, Nuclear Experiment, wave function [hadron], Physics, cross section, meson: electroproduction, Momentum transfer, thesis, exclusive reaction [electron p], parton [momentum spectrum], High Energy Physics - Phenomenology, momentum spectrum: parton, wave function: light cone, exclusive reaction [photon p], expansion: momentum transfer, tensor: energy-momentum, off-shell [Compton scattering], Compton scattering: off-shell, 020201 artificial intelligence & image processing, Compton scattering, Nucleon, coupling constant [strong interaction], electron p: deep inelastic scattering, Angular momentum, Particle physics, small-x, light cone [wave function], charmonium, hadron: spin, structure function [hadron], Structure (category theory), FOS: Physical sciences, Energy–momentum relation, angular momentum, interaction [photon photon], photon photon: interaction, Theoretical physics, Total angular momentum quantum number, factorization, 0103 physical sciences, photoproduction [meson], photon p: exclusive reaction, ddc:530, 010306 general physics, deep inelastic scattering [electron nucleus], Generalized normal distribution, electron nucleus: deep inelastic scattering, 010308 nuclear & particles physics, bibliography, 020206 networking & telecommunications, helicity, effect: higher-twist, meson: photoproduction, hadron: wave function, deep inelastic scattering [electron p], nucleon: spin, spin [nucleon], spin [hadron], angular momentum: parton, hadronization, electroproduction [meson]
Abstract

DESY, Diss., 2003; (2003). doi:10.1016/j.physrep.2003.08.002, We give an overview of the theory for generalized parton distributions. Topics covered are their general properties and physical interpretation, the possibility to explore the three-dimensional structure of hadrons at parton level, their potential to unravel the spin structure of the nucleon, their role in small-x physics, and efforts to model their dynamics. We review our understanding of the reactions where generalized parton distributions occur, to leading power accuracy and beyond, and present strategies for phenomenological analysis. We emphasize the close connection between generalized parton distributions and generalized distribution amplitudes, whose properties and physics we also present. We finally discuss the use of these quantities for describing soft contributions to exclusive processes at large energy and momentum transfer., Published by Elsevier Science, North-Holland, Amsterdam [u.a.]

Published
2003
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20. Electron deuteron scattering with HERA, a letter of intent for an experimental programme with the H1 detector

Author

Alexopoulos, T., Andreev, V., Aschenauer, E., Babaev, A., Backovic, S., Baranov, P., Barber, D., Belostotsky, S., Belousov, A., Bianchi, N., Bracinik, J., Brisson, V., Bruncko, D., Bunyatyan, A., Bystritskaya, L., Campbell, A. J., Shevyakov, I., Shtarkov, L., Ciullo, G., Contalbrigo, M., Contreras, J. G., Dainton, J. B., Dalpiaz, P., Danilov, M., Daum, K., De Sanctis, E., De Wolf, E. A., Di Nezza, P., Dodonov, V., Dris, M., Dubak, A., Efremenko, V., Eliseev, A., Esenov, S., Fantoni, A., Fedotov, A., Ferencei, J., Fomenko, A., Gavrilov, G., Gayler, Joerg, Gerhards, R., Ghazarian, S., Glazov, A. A., Goerlich, L., Gogitidze, N., Gorbov, L., Gorbunov, S., Grebenyuk, O., Greenshaw, T., Grindhammer, Guenter, Gustafson, G., Guzey, V., Haas, Tobias M., Hajduk, L., Haller, J., Haynes, W. J., Herynek, I., Hiller, K. H., Hovhannisyan, A., Ingelman, G., Jacquet, M., Jgoun, A., Jonsson, L., Jung, H., Kabuss, E., Kalburov, S., Kapishin, M., Karlsson, M., Kekelidze, V., Kenyon, I. R., Kiesling, Christian M., Kinney, E., Kiryushin, Y., Kiselev, A., Klein, M., Kostka, P., Knutsson, A., Kropivnitskaya, A., Kuhn, S. E., Lange, W., Lastovicka, T., Lebedev, A., Lendermann, V., Lenisa, P., Levonian, S., Lipka, K., Lobodzinska, E., Lonnblad, L., Loktionova, N., Lopez-Fernandez, R., Lundberg, B., Lytkin, L., Lubimov, V., Ma, B. Q., Makins, N., Malinovsky, E., Martyn, H. U., Martyniak, J., Medin, G., Mehta, A., Melnitchouk, W., Meyer, J., Mishin, S., Mikocki, S., Milstead, D., Mjornmark, U., Morozov, A., Muccifora, V., Murin, P., Nagovitsyn, V., Naryshkin, Yu., Naumann, T., Newman, Paul R., Niebuhr, C., Nikiforov, A., Nikitin, D., Nowak, G., Nowak, W. D., Olivier, B., Olsson, J. E., Usik, A., Ozerov, D., Pascaud, C., Patel, G. D., Peng, J. C., Pitzl, D., Povh, B., Raicevic, N., Reimer, P., Rith, K., Rizvi, E., Roosen, R., Rostovtsev, A., Rusakov, S., Sanjiev, I., Schilling, F. P., Schroder, V., Shekelian, V., Sjostrand, T., Sloan, T., Smirnov, P., Solovev, Yu., Soskov, V., Spaskov, V., Stella, B., Stewart, J., Stosslein, U., Cholakov, V., Thompson, Graham, Thompson, P., Traynor, D., Tsakov, I., Tsipolitis, Y., Tsurin, I., Turnau, J., Tytgat, M., Tzamariudaki, E., Uraev, A., Valkarova, A., Van Mechelen, P., Vazdik, Ya., Vikhrov, V., Vogt, M., Volchinsky, V., Wallny, R., Zacek, J., Zalesak, J., Zhang, Z., Zhelezov, A., Zhokin, A., and Zomer, F.

Subjects
colliding beams [electron deuteron], perturbation theory [quantum chromodynamics], small-x, generalized parton distribution, momentum spectrum [quark], diffraction, proposed experiment: DESY HERA Stor, electron deuteron: colliding beams, upgrade: proposed, calorimeter: readout, nonperturbative, structure function [nucleon], momentum spectrum [gluon], strong interaction: coupling constant, quark: recombination, proposed [upgrade], spin [photon], quantum chromodynamics: perturbation theory, numerical calculations, polarization, photon: spin, recombination [quark], high [momentum transfer], gluon: momentum spectrum, bibliography, nucleon: structure function, quark: momentum spectrum, DESY HERA Stor [proposed experiment], valence [quark], H1, proportional chamber, quark: valence, proposal, semiconductor detector, nucleon: spin, shadowing, readout [calorimeter], spin [nucleon], coupling constant [strong interaction], momentum transfer: high
Abstract

97 pp. (2003)., This document outlines the case for a programme of electron-deuteron scattering mea- surements at HERA using the H1 detector. The goals of the $e^\pm D$ programme are to map the partonic structure of the nucleon at large $Q^2$ and low $x$, to explore the valence quark distributions at the highest $x$ values, to provide a precise measurement of the strong coupling constant and to investigate the parton recombination phenomena revealed in shadowing and their relationship to diffraction. The importance of these measurements for the under- standing of the perturbative and non-perturbative aspects of QCD thought to be responsible for nucleon structure is discussed, as is the significance of the measurements for future experimental programmes. Some modifications to both the H1 apparatus and the HERA accelerator are necessary to realise this programme; these are presented in the document. Mention is also made of questions that will remain unanswered following the completion of the above programme and the potential role of HERA and of H1 in investigating these questions is outlined.Physicists and Institutes interested in supporting this project are asked to inform Max Klein (klein@ifh.de) and Tim Greenshaw (green@hep.ph.liv.ac.uk) that they would like to have their names on the Letter of Intent by Wednesday 30th April 2003.

Published
2003
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21. Generalized parton distributions. I

Author

Diehl, Markus

Subjects
meson: electroproduction, angular momentum, exclusive reaction [electron p], parton [momentum spectrum], momentum spectrum: parton, exclusive reaction [photon p], meson: photoproduction, hadron: wave function, photoproduction [meson], electron p: exclusive reaction, photon p: exclusive reaction, nucleon: spin, ddc:530, spin [nucleon], light cone, Compton scattering, electroproduction [meson], wave function [hadron]
Abstract

6 pp. (2002)., I give a brief introduction to generalized Parton distributions and to the phenomenology of the exclusive processes where they can be measured.

Published
2002
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22. Extraction of the polarized quark distributions of the nucleon at the HERMES experiment with emphasis on the sea quarks

Author

Lindemann, T.

Subjects
internal [polarized target], sea [quark], momentum spectrum [quark], deep inelastic scattering [positron deuteron], strangeness [nucleon], pi, HERMES [magnetic spectrometer], hadron: electroproduction, structure function [nucleon], dependence: flavor, electroproduction [hadron], nucleon: strangeness, deep inelastic scattering [positron p], tables, quark: sea, magnetic spectrometer: HERMES, positron p: deep inelastic scattering, flavor [dependence], 27.6 GeV, thesis, parametrization, bibliography, polarization [quark], nucleon: structure function, quark: momentum spectrum, structure function: polarization, DESY HERA Stor, positron deuteron: deep inelastic scattering, polarization [structure function], valence [quark], quark: valence, polarized target: internal, nucleon: spin, spin [nucleon], quark: polarization, asymmetry [spin], spin: asymmetry, experimental results
Abstract

Universität Hamburg, Diss., 2001; 211 pp. (2001). = Universität Hamburg, Diss., 2001

Published
2001
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23. Spin asymmetry of kaon productions in polarized deep-inelastic scattering on deuterium target by HERMES experiment

Author

Yoneyama, S.

Subjects
polarized beam [electron], electron: polarized beam, polarization: longitudinal, polarized target [deuterium], HERMES, +K+electron+anything%22">electron deuteron --> K electron anything, x-dependence, Cherenkov counter: experimental results, tables, longitudinal [polarization], experimental results [Cherenkov counter], thesis, bibliography, electron deuteron: deep inelastic scattering, K-: electroproduction, DESY HERA Stor, deuterium: polarized target, electroproduction [K+], electroproduction [K-], K+: electroproduction, nucleon: spin, deep inelastic scattering [electron deuteron], spin [nucleon], asymmetry [spin], spin: asymmetry
Abstract

Tokyo Institute of Technology - Department of Physics, Diss., 2001; 240 pp. (2001). = Tokyo Institute of Technology - Department of Physics, Diss., 2001

Published
2001
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24. Hard exclusive pseudoscalar meson electroproduction and spin structure of a nucleon

Author

Frankfurt, L. L., Pobylitsa, P. V., Polyakov, Maxim V., and Strikman, M.

Subjects
pi, baryon: electroproduction, photon: longitudinal, expansion 1/N: color, hard scattering, momentum spectrum: parton, symmetry: chiral, p: polarized target, electron nucleus: coherent interaction, pseudoscalar meson: electroproduction, quark: soliton, PCAC model, electron p: exclusive reaction, photon p: exclusive reaction, nucleon: spin, quantum chromodynamics: perturbation theory, numerical calculations, spin: asymmetry
Abstract

Physical review / D 60(1), 014010 (1999). doi:10.1103/PhysRevD.60.014010, The amplitude for hard exclusive pseudoscalar meson electroproduction off nucleon (nuclear) targets is computed in QCD within the leading $\alpha_s \ln {Q^2/\lambda_{QCD}^{2}}$ approximation. We show that the distribution of recoil nucleons depends strongly on the angle between the momentum of the recoil nucleon and the polarization vector of the target (or outgoing nucleon). This dependence is especially sensitive to the spin flip skewed parton distribution (SPD) $\widetilde E$. We argue also that the scaling for this spin asymmetry sets in at lower Q^2 than that for the absolute cross section. Basing on the chiral quark-soliton model of the nucleon we estimate quantitatively the spin asymmetry. In the case of pi+ production this asymmetry is dominated at small t by the contribution of the pion pole in the isovector SPD $\widetilde E$ as required by PCAC. In the case of K0 production off a proton we find a large enhancement of the cross section as compared to the case of pi0 production. For the forward production of neutral pseudoscalar mesons off a deuteron target we find the cross section should be zero for the zero deuteron helicity (along the $\gamma^*D$ direction). We consider also cross sections of quasielastic processes off nuclei including the feasibility to implant K+,rho-mesons into nuclear volume., Published by Inst., Woodbury, NY

Published
1999
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25. Measurement of the Polarized Quark Distributions of the Nucleon at HERMES

Author

Ruh, Michael and Königsmann, K.

Subjects
positron: polarized beam, sea [quark], momentum spectrum [quark], polarized target, HERMES, structure function [nucleon], 27.5 GeV, deep inelastic scattering [positron p], nuclide [helium], quark: sea, positron p: deep inelastic scattering, quark: flavor, thesis, lattice field theory, SU(3) [symmetry], bibliography, polarization [quark], nucleon: structure function, quark: momentum spectrum, positron nucleus: deep inelastic scattering, moment, DESY HERA Stor, deep inelastic scattering [positron nucleus], valence [quark], flavor [quark], quark: valence, symmetry: SU(3), nucleon: spin, polarized beam [positron], spin [nucleon], helium: nuclide, quark: polarization, experimental results
Abstract

137 pp. (1999)., The outline of this work is as follows. Chapter 2 gives an introduction to polarised deep inelastic scattering and provides the formalism used to extract the quark spin distributions from inclusive and semi-inclusive spin-dependcnt cross section asymmetries. In chapter 3 the HERMES experimental apparatus is introduced. The analysis of inclusive and semi-inclusive charged hadron asymmetries is presented in chapter 4 and the extraction of the polarised quark distributions from the measured cross section asymmetries is described in chapter 5. The HERMES results on the polarised quark distributions are discussed and compared to existing experimental results and to predictions from quark models and lattice QCD.

Published
1999
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26. The SMC Experiment: New Data on the Deuteron from the 1994 Run

Author

Baum, Günter, Boffi, Sigfrido, Ciofi Degli Atti, Claudio, and Giannini, Mauro

Subjects
deuteron: polarized target, polarized target: deuteron, Nuclear Theory, sum rule: Bjorken, deep inelastic scattering: muon+ p, FOS: Physical sciences, structure function: spin, muon+ deuteron: deep inelastic scattering, spin: nucleon, High Energy Physics - Experiment, x-dependence, asymmetry: polarization, quark: valence | polarization: asymmetry, High Energy Physics - Experiment (hep-ex), High Energy Physics - Phenomenology (hep-ph), hadron: multiple production, 100: 190 GeV/c, Nuclear Experiment, polarized beam: muon, moment: structure function, spin: structure function, deep inelastic scattering: muon+ deuteron, nucleon: structure function, talk: Trieste 1995/05/08, CERN SPS, quark: spin, magnetic spectrometer: experimental results, High Energy Physics - Phenomenology, muon+ p: deep inelastic scattering, multiple production: hadron, nucleon: spin, High Energy Physics::Experiment, muon: polarized beam, Particle Physics - Experiment, spin: quark
Abstract

An overview of the SMC data taking and the polarized deep inelastic scattering experiment is given. The new data on the deuteron extend the kinematic range and have considerably reduced statistical and systematic errors. The evaluation of the first moment of the spin dependent structure function is presented and the result for the Bjorken sum rule from SMC data alone is given. The spin contribution of the quarks to the spin of the nucleon is obtained with information from weak decays of baryons. In a new polarized semi-inclusive analysis the asymmetry of the difference between the number of positive and negative charged hadrons was studied. Preliminary results are shown., Comment: 14 pages including 8 figures, uuencoded gz-compressed ps-file, to be published in the Proceedings of the Seventh Conference on Perspectives in Nuclear Physics at Intermediate Energies, ICTP Trieste on 8-12 May 1995

Published
1995
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27. Community Support for A Fixed-Target Programme for the LHC

Author

Bjorken, J. D., Brodsky, S. J., Cleymans, J., Donato, F., Miguel G. Echevarria, Halzen, F., Hoyer, P., Kusina, A., Lansberg, J. P., Mulders, P. J., Pajares, C., Satz, H., Signori, A., Sivers, D., Strikman, M., Szymanowski, L., Martinez Vidal, F., Seixas, J., Brambilla, N., Institut de Physique Nucléaire d'Orsay (IPNO), and Centre National de la Recherche Scientifique (CNRS)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris-Sud - Paris 11 (UP11)

Subjects
[PHYS.NUCL]Physics [physics]/Nuclear Theory [nucl-th], Physics::Instrumentation and Detectors, [PHYS.HTHE]Physics [physics]/High Energy Physics - Theory [hep-th], nucleus, helium: target, p: beam, ion: beam, LHC-B, rapidity, ALICE, CERN LHC Coll, polarization: target, nuclear matter, [PHYS.HPHE]Physics [physics]/High Energy Physics - Phenomenology [hep-ph], [PHYS.HEXP]Physics [physics]/High Energy Physics - Experiment [hep-ex], luminosity, heavy quark, nucleon: spin, spin: asymmetry, quarkonium, performance, activity report
Abstract

This contribution aims at promoting the ground-breaking physics programme accessible with the multi-TeV LHC proton and ion beams used in the fixed-target mode. It can be realised in a parasitic mode for the LHC complex using existing detectors like those of the LHCb and ALICE collaborations or new dedicated systems during the LHC lifetime. It contains a brief description of the different technical implementations which are currently under investigation as well as the basic performances offered by the use of the ALICE and LHCb detectors in the fixed-target mode. In short, the multi-TeV LHC beams allow for the most energetic fixed-target experiment ever performed opening the way for unique studies of the nucleon and nuclear structure at high x, of the spin content of the nucleon and of the phases of the nuclear matter from a new rapidity viewpoint at seldom explored energies.

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