Regular Article

Line shape analysis of the Kβ transition in muonic hydrogen

¹ LIBPhys, Physics Department, University of Coimbra, 3004-526 Coimbra, Portugal
² Laboratory for Particle Physics, Paul Scherrer Institut, CH-5232 Villigen, Switzerland
³ Department of Materials Science and Engineering, University of Ioannina, 45110 Ioannina, Greece
⁴ Stefan Meyer Institute for Subatomic Physics, Austrian Academy of Sciences, 1090 Vienna, Austria
⁵ Zentralinstitut für Elektronik, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
⁶ Institut für Kernphysik, Forschungszentrum Jülich, 52425 Jülich, Germany
⁷ Laboratoire Kastler Brossel, Sorbonne Universités, UPMC Univ. Paris 06, Case 74, 4 Place Jussieu, 75005 Paris, France
⁸ Laboratoire Kastler Brossel, CNRS, 75005 Paris, France
⁹ Laboratoire Kastler Brossel, Département de Physique de l’École Normale Supérieure, 24 Rue Lhomond, 75005 Paris, France
¹⁰ Institut für Theoretische Physik Universität Zürich, CH-8057 Zürich, Switzerland
¹¹ Skobeltsyn Institut of Nuclear Physics, Lomonosov Moscow State University, 119991 Moscow, Russia
¹² Institut des NanoSciences de Paris, CNRS-UMR 7588, Sorbonne Universités, UPMC Univ. Paris 06, 75005 Paris, France
¹³ I3N, Department of Physics, Aveiro University, 3810 Aveiro, Portugal

^b e-mail: d.gotta@fz-juelich.de

Received: 18 September 2017
Received in final form: 20 February 2018
Published online: 30 April 2018

Abstract

The Kβ transition in muonic hydrogen was measured with a high-resolution crystal spectrometer. The spectrum is shown to be sensitive to the ground-state hyperfine splitting, the corresponding triplet-to-singlet ratio, and the kinetic energy distribution in the 3p state. The hyperfine splitting and triplet-to-singlet ratio are found to be consistent with the values expected from theoretical and experimental investigations and, therefore, were fixed accordingly in order to reduce the uncertainties in the further reconstruction of the kinetic energy distribution. The presence of high-energetic components was established and quantified in both a phenomenological, i.e. cascade-model-free fit, and in a direct deconvolution of the Doppler broadening based on the Bayesian method.