Design of the Magnet System of the Neutron Decay Facility PERC

Xiangzun Wang; Carmen Ziener; Hartmut Abele; Stefan Bodmaier; Dirk Dubbers; Jaqueline Erhart; Alexander Hollering; Erwin Jericha; Jens Klenke; Harald Fillunger; Werner Heil; Christine Klauser; Gertrud Konrad; Max Lamparth; Thorsten Lauer; Michael Klopf; Reinhard Maix; Bastian Märkisch; Wilfried Mach; Holger Mest; Daniel Moser; Alexander Pethoukov; Lukas Raffelt; Nataliya Rebrova; Christoph Roick; Heiko Saul; Ulrich Schmidt; Torsten Soldner; Romain Virot; Oliver Zimmer

doi:10.1051/epjconf/201921904007

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arXiv · 1905.10249

Design of the Magnet System of the Neutron Decay Facility PERC

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Abstract

The PERC (Proton and Electron Radiation Channel) facility is currently under construction at the research reactor FRM II, Garching. It will serve as an intense and clean source of electrons and protons from neutron beta decay for precision studies. It aims to contribute to the determination of the Cabibbo-Kobayashi-Maskawa quark-mixing element $V_{ud}$ from neutron decay data and to search for new physics via new effective couplings. PERC's central component is a 12m long superconducting magnet system. It hosts an 8m long decay region in a uniform field. An additional high-field region selects the phase space of electrons and protons which can reach the detectors and largely improves systematic uncertainties. We discuss the design of the magnet system and the resulting properties of the magnetic field.

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Xiangzun Wang, Carmen Ziener, Hartmut Abele, Stefan Bodmaier, Dirk Dubbers, Jaqueline Erhart, Alexander Hollering, Erwin Jericha, Jens Klenke, Harald Fillunger, Werner Heil, Christine Klauser, Gertrud Konrad, Max Lamparth, Thorsten Lauer, Michael Klopf, Reinhard Maix, Bastian Märkisch, Wilfried Mach, Holger Mest, Daniel Moser, Alexander Pethoukov, Lukas Raffelt, Nataliya Rebrova, Christoph Roick, Heiko Saul, Ulrich Schmidt, Torsten Soldner, Romain Virot, Oliver Zimmer. 2019-05-24. Design of the Magnet System of the Neutron Decay Facility PERC. https://doi.org/10.1051/epjconf/201921904007

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