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Related papers: Polarized Protons in HERA

200 papers

The main goals of `spin physics' are recalled, and some theoretical and phenomenological aspects of longitudinally polarized deep inelastic scattering and other hard processes are reviewed. The spin dependent parton densities of protons and…

High Energy Physics - Phenomenology · Physics 2007-05-23 M. Stratmann

We study the prospects for HERA with polarized electron and/or proton beams to determine the functions describing the fragmentation of a longitudinally polarized parton into a polarized Lambda baryon. We examine both semi-inclusive…

High Energy Physics - Phenomenology · Physics 2007-05-23 D. de Florian , M. Stratmann , W. Vogelsang

We consider the possibility of a direct determination of the polarized gluon density in the proton using charm production with polarized beams at HERA. We study total cross sections and distributions at leading order using different…

High Energy Physics - Phenomenology · Physics 2011-07-19 S. Frixione , G. Ridolfi

In situ generation of a high-energy, high-current, spin-polarized electron beam is an outstanding scientific challenge to the development of plasma-based accelerators for high-energy colliders. In this Letter we show how such a…

Polarized antiprotons can be produced in a storage ring by spin--dependent interaction in a purely electron--polarized hydrogen gas target. The polarizing process is based on spin transfer from the polarized electrons of the target atoms to…

A method of generating spin polarized proton beams from a gas jet by using a multi-petawatt laser is put forward. With currently available techniques of producing pre-polarized monatomic gases from photodissociated hydrogen halide molecules…

Plasma Physics · Physics 2020-07-29 Luling Jin , Meng Wen , Xiaomei Zhang , Anna Hützen , Johannes Thomas , Markus Büscher , Baifei Shen

We propose a filter method to generate electron beams of high polarization from bubble and blow-out wakefield accelerators. The mechanism is based on the idea to identify all electron-beam subsets with low-polarization and to filter them…

The physics scope of a possible future experiment utilizing an internal polarized nucleon target in the HERA proton beam is discussed. By measuring single spin asymmetries in inclusive particle production at 820~GeV beam energy the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wolf-Dieter Nowak

Relativistic positron sources with high spin polarization have important applications in nuclear and particle physics and many frontier fields. However, it is challenging to produce dense polarized positrons. Here we present a simple and…

Plasma Physics · Physics 2024-05-22 Xing-Long Zhu , Wei-Yuan Liu , Tong-Pu Yu , Min Chen , Su-Ming Weng , Wei-Min Wang , Zheng-Ming Sheng

The acceleration of polarized electron beams in the blowout regime of plasma-based acceleration is explored. An analytical model for the spin precession of single beam electrons, and depolarization rates of zero emittance electron beams, is…

Accelerator Physics · Physics 2011-08-22 J. Vieira , C. -K. Huang , W. B. Mori , L. O. Silva

A brief review is given of the status of nucleon spin structure functions as determined from polarized deep inelastic lepton-nucleon scatttering, including current outstanding problems. The characteristics of a polarized HERA collider, some…

High Energy Physics - Experiment · Physics 2009-10-31 V. W. Hughes , A. Deshpande

We discuss polarized proton-positron scattering in the context of the excess of large $Q^2$ events at HERA. We define and estimate a polarized asymmetry to examine two scenarios, the contact interaction and the stop scenario with broken…

High Energy Physics - Phenomenology · Physics 2009-10-31 J. Hashida , Y. Kiyo

Relativistic spin-polarized positron beams are indispensable for future electron-positron colliders to test modern high-energy physics theory with high precision. However, present techniques require very large scale facilities for those…

From the point of view of the R-parity breaking supersymmetric model, we propose a scalar top (stop) search with longitudinally polarized electron (e-) and positron(e+) beams which will soon be available at the upgraded HERA. Fully…

High Energy Physics - Phenomenology · Physics 2011-03-23 Shoichi Kitamura , Tadashi Kon , Tetsuro Kobayashi

The acceleration of polarized electrons, positrons, protons and ions in strong laser and plasma fields is a very attractive option to obtain polarized beams in the multi-MeV range. Recently, there has been substantial progress in the…

Accelerator Physics · Physics 2020-11-04 Markus Büscher , Anna Hützen , Liangliang Ji , Andreas Lehrach

We propose a method for polarising antiprotons in a storage ring by means of a polarised positron beam moving parallel to the antiprotons. If the relative velocity is adjusted to $v/c \approx 0.002$ the cross section for spin-flip is as…

Accelerator Physics · Physics 2009-02-19 Th. Walcher , H. Arenhoevel , K. Aulenbacher , R. Barday , A. Jankowiak

The generation of polarized particle beams still relies on conventional particle accelerators, which are typically very large in scale and budget. Concepts based on laser-driven wake-field acceleration have strongly been promoted during the…

A summary is given on the physics potential of measuring singly polarized proton--nucleon collisions using a polarized internal target in the 820 GeV HERA proton beam. This summary is based upon talks given at the 2nd Meeting on 'Possible…

High Energy Physics - Phenomenology · Physics 2007-05-23 Wolf-Dieter Nowak

Estimates for longitudinal spin asymmetries which single out new polarized nucleon structure functions in deeply inelastic charged current interactions at HERA energies are given, exploiting their interpretation in terms of polarized quark…

High Energy Physics - Phenomenology · Physics 2009-10-28 M. Anselmino , P. Gambino , J. Kalinowski