TY  - GEN
AV  - public
A1  - Allmendinger, Fabian
N2  - Effects of theories beyond the Standard Model would become directly apparent at high energies, which are probably out of reach for colliders. As an alternative, low-energy
high-precision measurements of quantities are performed, looking for deviations from the Standard Model (SM) predictions. In this case: Firstly, a small amount of the large effects of quantum gravity at the Planck scale should remain at low energies, which is tested by looking for Lorentz invariance violation in the neutron sector. Secondly, new sources of CP-violation would cause permanent electric dipole moments (EDMs)of particles that are many orders of magnitude larger than the EDMs predicted by
the SM. The experimental approach is to measure the free precession of nuclear spin polarized 3He and 129Xe atoms in a homogeneous magnetic guiding field of about 400 nT using LTC SQUIDs as low-noise magnetic flux detectors. This dissertation reports on the search for a CPT and Lorentz invariance violating coupling of the 3He and 129Xe nuclear spins to posited background fields. An upper limit on the
equatorial component of the background field interacting with the spin of the bound
neutron bn < 8.4 10^-34 GeV (68% C.L.) was obtained. Furthermore, the technical developments and preparations for measurements of the 129Xe EDM are described.
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/18104/
ID  - heidok18104
TI  - Precise Tests of Fundamental Symmetries at Low Energies
using a 3He-129Xe Comagnetometer
Y1  - 2015///
ER  -