Europhys. Lett.
Volume 76, Number 5, December 2006
Page(s) 794 - 800
Section The physics of elementary particles and fields
Published online 03 November 2006
Europhys. Lett., 76 (5), pp. 794-800 (2006)
DOI: 10.1209/epl/i2006-10356-5

Accelerator cavities as a probe of millicharged particles

H. Gies1, J. Jaeckel2 and A. Ringwald2

1  Institut für Theoretische Physik, Universität Heidelberg - Philosophenweg 16 D-69120 Heidelberg, Germany
2  Deutsches Elektronen-Synchrotron DESY - Notkestraße 85 D-22607 Hamburg, Germany

received 29 August 2006; accepted 9 October 2006
published online 3 November 2006

We investigate Schwinger pair production of millicharged fermions in the strong electric field of cavities used for particle accelerators. Even without a direct detection mechanism at hand, millicharged particles, if they exist, contribute to the energy loss of the cavity and thus leave an imprint on the cavity's quality factor. Already conservative estimates substantially constrain the electric charge of these hypothetical particles; the resulting bounds are competitive with the currently best laboratory bounds which arise from experiments based on polarized laser light propagating in a magnetic field. We propose an experimental setup for measuring the electric current comprised of the millicharged particles produced in the cavity.

12.20.Fv - Quantum electrodynamics: Experimental tests.
14.80.-j - Other particles (including hypothetical).

© EDP Sciences 2006