https://doi.org/10.1140/epja/i2015-15089-8
Regular Article - Experimental Physics
Preparatory studies for a high-precision Penning-trap measurement of the 163Ho electron capture Q-value
1
Institut für Kernchemie, Johannes Gutenberg-Universität, 55128, Mainz, Germany
2
Institut für Physik, Johannes Gutenberg-Universität, 55128, Mainz, Germany
3
Max-Planck-Institut für Kernphysik, 69117, Heidelberg, Germany
4
GSI Helmholtzzentrum für Schwerionenforschung GmbH, 64291, Darmstadt, Germany
5
Helmholtz-Institut Mainz, 55099, Mainz, Germany
6
Physical Faculty, Saint Petersburg State University, 199034, Saint Petersburg, Russia
7
Paul Scherrer Institute, 5232, Villigen, Switzerland
8
Universität Bern, 3012, Bern, Switzerland
9
PRISMA Cluster of Excellence, Johannes Gutenberg-Universität, 55099, Mainz, Germany
10
Institut Laue-Langevin, 38000, Grenoble, France
* e-mail: Fabian.Schneider@uni-mainz.de
Received:
6
March
2015
Accepted:
25
June
2015
Published online:
22
July
2015
The ECHo Collaboration (Electron Capture 163Ho aims to investigate the calorimetric spectrum following the electron capture decay of 163Ho to determine the mass of the electron neutrino. The size of the neutrino mass is reflected in the endpoint region of the spectrum, i.e., the last few eV below the transition energy. To check for systematic uncertainties, an independent determination of this transition energy, the Q-value, is mandatory. Using the TRIGA-TRAP setup, we demonstrate the feasibility of performing this measurement by Penning-trap mass spectrometry. With the currently available, purified 163Ho sample and an improved laser ablation mini-RFQ ion source, we were able to perform direct mass measurements of 163Ho and 163Dy with a sample size of less than 1017 atoms. The measurements were carried out by determining the ratio of the cyclotron frequencies of the two isotopes to those of carbon cluster ions using the time-of-flight ion cyclotron resonance method. The obtained mass excess values are ME(163Ho)= −66379.3(9) keV and ME(163Dy)= −66381.7(8) keV. In addition, the Q-value was measured for the first time by Penning-trap mass spectrometry to be Q = 2.5(7) keV.
© SIF, Springer-Verlag Berlin Heidelberg, 2015