0000000000185917
AUTHOR
Yuri Sobolev
Spin clocks: Probing fundamental symmetries in nature
The detection of the free precession of co-located 3He/129Xe nuclear spins (clock comparison) is used as ultra-sensitive probe for non-magnetic spin interactions, since the magnetic dipole interaction (Zeeman-term) drops out in the weighted frequency difference, i.e., Δω = ωHe- γHe/γXe·ωXe of the respective Larmor frequencies. Recent results are reported on searches for (i) short-range P- and T-violating interactions between nucleons, and (ii) Lorentz violating signatures by monitoring the Larmor frequencies as the laboratory reference frame rotates with respect to distant stars (sidereal modulation). Finally, a new experimental initiative to search for an electric dipole moment of 129Xe (C…
Spin-parity of the 13.35 MeV state and high-lying states around 20 MeV in excitation energy in 12C nucleus
A study of the 11B(3He,d)12C reaction at incident 3He energy Elab = 25 MeV has been performed at the K-130 cyclotron at the University of Jyväskylä, Finland. Differential cross sections have been measured for the 13.35 MeV state and for the states with excitation energy around 20 MeV in 12C. The data were analyzed with the DWBA method. A tentative assignment, 4−, is given for the state at 13.35 MeV in a joint study of the reaction and inelastic scattering of α-particles with the energy of 110 MeV. For the state at 20.98 MeV, the possible spin-parity 3− and the isospin T =0 are assigned for the first time. Our model description of the broad state at 21.6 MeV is consistent with the previous as…
Constraints on Spin-Dependent Short-Range Interaction between Nucleons
We report on the search for a new spin-dependent P- and T-violating interaction between nucleons mediated by light, pseudoscalar bosons such as the axion which was invented to solve the strong CP problem. Our experimental approach is to use an ultra-sensitive low-field magnetometer based on the detection of free precession of co-located 3He and 129Xe nuclear spins using SQUIDs as low-noise magnetic flux detectors. In the presence of an unpolarized mass the precession frequency shif
Search for Spin-Dependent Short-Range Interaction with an 3He/129Xe Clock Comparison Experiment
We performed an experiment to search for a new spin-dependent P- and T-violating nucleon–nucleon interaction [Formula: see text] which is mediated by light pseudoscalar bosons such as axions or axionlike particles. This interaction causes a shift [Formula: see text] in the precession frequency of nuclear spin polarized gases in the presence of an unpolarized mass. In order to measure this frequency shift a 3He/[Formula: see text]Xe comagnetometer was used which is based on the detection of free precession of 3He and [Formula: see text]Xe nuclear spins using SQUIDs as detectors. For the upper limit of [Formula: see text] we obtained 7.1[Formula: see text]nHz. With this value, an upper limit…