AP-Seminare

# Spectroscopy of highly charged ions at the ALPHATRAP experiment

## by Alexander Egl (MPIK)

Wednesday, April 17, 2019 from to (Europe/Berlin)
at GSI ( KBW Lecture Hall - Side Room )
 Description The ALPHATRAP experiment at the Max-Planck-Institut für Kernphysik is a cryogenic Penning-trap setup to perform high-precision g-factor measurements on highly charged ions (HCI) up to hydrogenlike 208Pb81+. HCI are excellent candidates to test fundamental theories such as bound-state quantum electrodynamics (BS-QED) in strong fields. Furthermore, ALPHATRAP can provide access to fundamental constants, such as the fine-structure constant α or the electron’s atomic mass. We completed our first measurement campaigns dedicated to the determination of the ground-state g-factor of a single boronlike 40Ar13+ achieving a few parts per billion precision measurement. In the second campaign we recently performed laser spectroscopy of an electric-dipole-forbidden fine structure transition (2𝑝 2𝑃1/2− 2𝑃3/2) with a single 40Ar13+ ion, using a novel method that does not rely on any fluorescence signal which allows finding straight forward a transition by using the continuous Stern Gerlach effect. In this talk an overview over the ALPHATRAP experiment and techniques is given and first results will be presented.