Creating highly charged ions of very rare isotopes

DEC 06, 2019

Researchers have developed a new technique to produce highly charged ions of rare isotopes, which they plan to use in neutrino mass studies.

Anashe Bandari

DOI: 10.1063/10.0000377

Creating highly charged ions of very rare isotopes internal name — Creating highly charged ions of very rare isotopes lead image

The mechanisms governing the existence of a finite neutrino mass remain one of the open questions in modern physics, and a more precise measurement of the neutrino mass may shed light on this mystery. The Electron Capture in Holmium (ECHo) collaboration aims to achieve a sub-electron-volt measurement of the electron neutrino mass. A new paper by the Pentatrap group, a part of the ECHo collaboration, proposes a unique technique to efficiently produce highly charged ions of a rare isotope of holmium, ¹⁶³Ho, for potential contributions to neutrino mass investigations.

The group developed the new method by combining two common experimental techniques – pulsed laser ablation and electron beam ion traps. First, pulsed laser ablation is used to remove small quantities of atoms and ions from the surface of the sample inside the ion trap to produce highly charged ions, which are then loaded into PENTATRAP, a high-precision Penning trap mass spectrometer. PENTATRAP is then used to determine the amount of energy available for decay. This parameter, called the Q-value, reflects the mass difference of the nuclides before and after decay.

“The presented technique allows the production of highly charged ions of the very rare isotope ¹⁶³Ho for a high-precision measurement of the Q-value with Pentatrap, and is therefore an essential part of the neutrino mass investigation,” said author Christoph Schweiger.

The authors said they are ready to begin taking data to measure the Q-value for electron capture decay from ¹⁶³Ho. They note this method can be used to produce other types of highly charged ions and expand on the range of rare isotopes.

Source: “Production of highly charged ions of rare species by laser-induced desorption inside an electron beam ion trap,” by Ch. Schweiger, C. M. König, J. R. Crespo López-Urrutia, M. Door, H. Dorrer, C. E. Düllmann, S. Eliseev, P. Filianin, W. Huang, K. Kromer, P. Micke, M. Müller, D. Renisch, A. Rischka, R. X. Schüssler, and K. Blaum, Review of Scientific Instruments (2019). The article can be accessed at https://doi.org/10.1063/1.5128331 .