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Perspectives on High-Luminosity Muon-Nucleon Experiments
Nuclear Physics B (Proc. Suppl.) 147 (2005) 141 www.elsevierphysics.com
Perspectives on High-Luminosity Muon-Nucleon Experiments Wolf-Dieter Nowaka a
DESY, Platanenallee 6, D-15738 Zeuthen, Germany
Perspectives are discussed on fixed-target muon-nucleon scattering experiments using polarized and unpolarized beams and targets in various combinations. The goal envisioned is a deep and complete understanding of the momentum and spin structure of hadrons in the context of Quantum Chromodynamics, based on measurements at moderate and low photon virtualities. This program can be realized by performing muon-nucleon experiments with high resolution and high luminosity, in the beam energy range 30-200 GeV.
Over more than two decades the momentum and spin structure of single partons in the nucleon has been investigated by now, preferentially using charged leptons as probe(s). A great variety of measurements, performed in fixed-target and collider experiments, turned Quantum Chromodynamics (QCD) from a candidate theory into the widely accepted field theory of strong interactions. Large enough photon virtualities Q2 were required to successfully test the abilities of perturbative QCD to describe short-range phenomena. In contrast, the description of long-range phenomena and especially of parton correlations in hadrons, over a broad range in Q2 , is still in its infancy.
principle be produced either conventionally as a tertiary beam from protons through a kaon/pion decay beam line, or it can be ejected from a possible future muon collider. A variety of experimental questions remains to be addressed when thinking about target and spectrometer for a high-luminosity muon-nucleon experiment including doubly polarized running mode. Certain aspects have already been discussed in two recent proposals based on electron beams [3,4]. It appears feasible in principle to accomplish most of these goals by a future upgrade of the COMPASS [5] target and spectrometer.
Based on recent theoretical developments in the field, in two recent publications [1,2] experimentalist’s perspectives were described on physics prospects for possible future electronnucleon fixed-target experiments in the beam energy range 30-200 GeV, with high resolution, high luminosity and polarized beams or targets. Projections were given for future high-luminosity measurements of polarized quark and gluon distributions, as well as for first attempts to explore the angular momentum structure of the nucleon through measurements of Generalized Parton Distributions.
1. W.-D. Nowak, Nucl. Phys. B (Proc. Suppl.) 105 (2002) 171-177. 2. W.-D. Nowak, in: Spin Structure of the Nucleon, ed.s E. Steffens and R. Shanidze, NATO Science Series, II. Mathematics, Physics and Chemistry - Vol. 111, 37-49. 3. M. Anselmino et al., ELFE: Physics Motivations, NuPECC Report, Sept. 2001. in: TESLA Technical Design Report, DESY 2001-011, Part VI, Appendices. 4. M. Anselmino et al., TESLA-N: DESY 00160, hep-ph/0011299 in: TESLA Technical Design Report, DESY 2001-011, Part VI. 5. The COMPASS Collaboration, Common Muon and Proton Apparatus for Structure and Spectroscopy, CERN/SPSLC 96-14, SPSC/P297, March 1, 1996
Because of lepton universality, muon-nucleon scattering can serve the same physics purpose. In the future a high intensity muon beam can in 0920-5632/$ – see front matter © 2005 Published by Elsevier B.V. doi:10.1016/j.nuclphysbps.2005.03.017
REFERENCES
Perspectives on High-Luminosity Muon-Nucleon Experiments Wolf-Dieter Nowaka a
DESY, Platanenallee 6, D-15738 Zeuthen, Germany
Perspectives are discussed on fixed-target muon-nucleon scattering experiments using polarized and unpolarized beams and targets in various combinations. The goal envisioned is a deep and complete understanding of the momentum and spin structure of hadrons in the context of Quantum Chromodynamics, based on measurements at moderate and low photon virtualities. This program can be realized by performing muon-nucleon experiments with high resolution and high luminosity, in the beam energy range 30-200 GeV.
Over more than two decades the momentum and spin structure of single partons in the nucleon has been investigated by now, preferentially using charged leptons as probe(s). A great variety of measurements, performed in fixed-target and collider experiments, turned Quantum Chromodynamics (QCD) from a candidate theory into the widely accepted field theory of strong interactions. Large enough photon virtualities Q2 were required to successfully test the abilities of perturbative QCD to describe short-range phenomena. In contrast, the description of long-range phenomena and especially of parton correlations in hadrons, over a broad range in Q2 , is still in its infancy.
principle be produced either conventionally as a tertiary beam from protons through a kaon/pion decay beam line, or it can be ejected from a possible future muon collider. A variety of experimental questions remains to be addressed when thinking about target and spectrometer for a high-luminosity muon-nucleon experiment including doubly polarized running mode. Certain aspects have already been discussed in two recent proposals based on electron beams [3,4]. It appears feasible in principle to accomplish most of these goals by a future upgrade of the COMPASS [5] target and spectrometer.
Based on recent theoretical developments in the field, in two recent publications [1,2] experimentalist’s perspectives were described on physics prospects for possible future electronnucleon fixed-target experiments in the beam energy range 30-200 GeV, with high resolution, high luminosity and polarized beams or targets. Projections were given for future high-luminosity measurements of polarized quark and gluon distributions, as well as for first attempts to explore the angular momentum structure of the nucleon through measurements of Generalized Parton Distributions.
1. W.-D. Nowak, Nucl. Phys. B (Proc. Suppl.) 105 (2002) 171-177. 2. W.-D. Nowak, in: Spin Structure of the Nucleon, ed.s E. Steffens and R. Shanidze, NATO Science Series, II. Mathematics, Physics and Chemistry - Vol. 111, 37-49. 3. M. Anselmino et al., ELFE: Physics Motivations, NuPECC Report, Sept. 2001. in: TESLA Technical Design Report, DESY 2001-011, Part VI, Appendices. 4. M. Anselmino et al., TESLA-N: DESY 00160, hep-ph/0011299 in: TESLA Technical Design Report, DESY 2001-011, Part VI. 5. The COMPASS Collaboration, Common Muon and Proton Apparatus for Structure and Spectroscopy, CERN/SPSLC 96-14, SPSC/P297, March 1, 1996
Because of lepton universality, muon-nucleon scattering can serve the same physics purpose. In the future a high intensity muon beam can in 0920-5632/$ – see front matter © 2005 Published by Elsevier B.V. doi:10.1016/j.nuclphysbps.2005.03.017
REFERENCES