Proposed precision laser spectrometer for trapped, highly charged ions

Abstract

We propose a type of precision laser spectrometer for trapped, highly charged ions nearly at rest. It consists of a cylindrical, open-endcap Penning trap in which an externally produced bunch of highly charged ions can be confined and investigated by means of laser spectroscopy. The combination of confinement, cooling, and compression of a dense ion cloud will allow the ground-state hyperfine splitting in highly charged ions to be measured with an accuracy three orders of magnitude better than in any previous experiment. A systematic study of different charge states and different isotopes of the same element allows for highly sensitive tests of bound-state quantum electrodynamics and for a precision determination of nuclear properties. Apart from stable isotopes, radioactive species with half-lives longer than about 1 hour also can be investigated.

Rapid crystallization of externally produced ions in a Penning trap

“…The experiments were performed with the SpecTrap experiment [18,25] located at the HITRAP facility [26] at GSI and FAIR, Germany. The experimental setup ( Fig.…”

Half-open Penning trap with efficient light collection for precision laser spectroscopy of highly charged ions

“…The fraction of the light power arriving at each end face is close to 20 % of the total emitted power due to the angular intensity distribution (6). To illustrate light collection, figure 4 shows a false-colour CCD image of a fluorescing ion cloud confined in the trap as seen from above through the mesh.…”

“…A sixth-order perturbation c 6 (z/d) 6 can be calculated from equation (4) when an effective fourth-order termc…”

“…In this design, the light collection efficiency is limited by the required ratio of diameter to length of the arrangement. Radial trap openings as used in experiments like [5,6,7] circumvent this limitation, but are likely to be unsuitable when high precision of the confining fields comparable to experiments like [8,9,10,11] is required. Also, they necessitate either complicated light collection schemes [5] or radial access to the trap [6,7].…”

“…Radial trap openings as used in experiments like [5,6,7] circumvent this limitation, but are likely to be unsuitable when high precision of the confining fields comparable to experiments like [8,9,10,11] is required. Also, they necessitate either complicated light collection schemes [5] or radial access to the trap [6,7]. Open access to confined particles has been a good part of the motivation when designing planar Penning traps [12,13,14,15,16] as well as numerous other types of traps such as wire Penning traps [17], stylus traps [18] and others [19,20,21].…”