Performance of phase II of the project: Construction and performance of an experiment to determine a possible electric charge of the free neutron with a sensitivity of gamma qn = 10-22qe.

• Applicant: Professor Dr. Tobias Reich, since 4/2014
• Subject Area: Nuclear and Elementary Particle Physics, Quantum Mechanics, Relativity, Fields
• Term: from 2010 to 2016
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 167645125

The investigation of the fundamental properties of the neutron is closely related to astroparticle physics. Besides the search for an electric dipole moment of the neutron and the precise determination of its life time, the question of its electric neutrality is of certain interest. This is related to the quantization of the electric charge. Being an empirical well-established finding, it cannot be derived however straightforward from the theoretical structure of the Standard Model. A dequantization of the electric charge could result in so-called ’rest-charges’ of the known particles like the neutron. Our project aims to measure the neutron charge with a precision of δqn= 10-22qe and with ultracold neutrons. Since April 2008 we carried out preliminary work and investigated systematic effects which concern such an experiment. In the second phase we will realize the high voltage system, define the further used materials and fix the mechanical setup. The milestones should be reached during 2 years of development after which we will begin with the construction of the experiment itself.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1491: Precision Experiments in Particle- and Astrophysics with Cold and Ultracold Neutrons
• Ehemaliger Antragsteller: Professor Dr. Christian Plonka-Spehr, until 3/2014