0000000000633975
AUTHOR
Lorenz Willmann
A new limit of the 129 Xenon Electric Dipole Moment
We report on the first preliminary result of our 129Xe EDM measurement performed by the MIXed collaboration. The aim of this report is to demonstrate the feasibility of a new method to set limits on nuclear EDMs by investigating the EDM of the diamagnetic 129Xe atoms. In our setup, hyperpolarized 3He serves as a comagnetometer needed to suppress magnetic field fluctuations. The free induction decay of the two polarized spin species is directly measured by low noise DC SQUIDs, and the weighted phase difference extracted from these measurements is used to determine a preliminary upper limit on the 129Xe EDM.
Nuclear structure with radioactive muonic atoms
Muonic atoms have been used to extract the most accurate nuclear charge radii based on the detection of X-rays from the muonic cascades. Most stable and a few unstable isotopes have been investigated with muonic atom spectroscopy techniques. A new research project recently started at the Paul Scherrer Institut aims to extend the highresolution muonic atom spectroscopy for the precise determination of nuclear charge radii and other nuclear structure properties of radioactive isotopes. The challenge to combine the high-energy muon beam with small quantity of stopping mass is being addressed by developing the concept of stopping the muon in a high-density, a high-pressure hydrogen cell and sub…
HP-Xe to go: Storage and Transportation of Hyperpolarized 129-Xe
Abstract Recently the spin–lattice relaxation time T 1 of hyperpolarized (HP)- 129 Xe was significantly improved by using uncoated and Rb-free storage vessels of GE180 glass. For these cells, a simple procedure was established to obtain reproducible wall relaxation times of about 18 h. Then the limiting relaxation mechanism in pure Xe is due to the coupling between the nuclear spins and the angular momentum of the Xe–Xe van-der-Waals-molecules. This mechanism can be significantly reduced by using different buffer gases of which CO 2 was discovered to be the most efficient so far. From these values, it was estimated that for a 1:1 mixture of HP-Xe with CO 2 a longitudinal relaxation time of …
Measurement of the quadrupole moment of Re185 and Re187 from the hyperfine structure of muonic X rays
The hyperfine splitting of the 5g→4f transitions in muonic Re185,187 has been measured using high resolution high purity germanium detectors and compared to state-of-the-art atomic theoretical predictions. The spectroscopic quadrupole moment has been extracted using modern fitting procedures and compared to the values available in literature obtained from muonic x rays of natural rhenium. The extracted values of the nuclear spectroscopic quadrupole moment are 2.07(5) b and 1.94(5) b, respectively for Re185 and Re187.