Decay of the vortex muon

Abstract

Muon decay is self-analyzing: the spectral-angular distribution of the emitted electron reveals the spin orientation of the polarized muon. Here, we show that the same feature applies to muons in non-plane-wave states and helps reveal the rich polarization opportunities available. We focus on the so-called vortex states, in which the muon carries a non-zero orbital angular momentum with respect to the average propagation direction and exhibits a cone structure in the momentum distribution. We compute the spectrum and the angular distribution of the electrons emitted in decays of vortex muons and show that the most revealing observable is not the angular distribution but the fixed-angle electron spectra. Even for very small cone opening angles of the vortex muons, it will be easy to observe significant modifications of the electron spectra which would allow one to distinguish vortex muons from approximately plane wave muons, as well as to differentiate among various polarization states. These features will be the key to tracking the evolution of vortex muons in external magnetic fields.

12 pages, 8 figures; v2: a numerical error corrected, plots updated, text improved, the main results stay unchanged, matches the published version. v3: Fig.8 is corrected, the other results remain unchanged

References in corpus (12)

• Semiclassical Dynamics of Electron Wave Packet States with Phase Vortices
• Muon g-2: Review of Theory and Experiment
• Colliding particles carrying non-zero orbital angular momentum
• Twisted electron in a strong laser wave
• Compton scattering of twisted light: angular distribution and polarization of scattered photons
• Elastic scattering of vortex electrons provides direct access to the Coulomb phase
• Scattering of wave packets with phases
• Scattering of twisted electron wave-packets by atoms in the Born approximation
• Radiative recombination of twisted electrons with bare nuclei: going beyond the Born approximation
• Kinematic surprises in twisted particle collisions
• Probing phase of a scattering amplitude beyond the plane-wave approximation
• Vortex particles in axially symmetric fields and applications of the quantum Busch theorem

Cited by in corpus (5)

• Promises and challenges of high-energy vortex states collisions
• Dynamical control of nuclear isomer depletion via electron vortex beams
• Generation of vortex particles via generalized measurements
• $Z_n$ symmetry in the vortex muon decay
• Nuclear Excitation by Muon Capture