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Abstract

The goal of this bachelor thesis is setting up a temperature stabilization of
the ultra-stable voltage source StaReP - Stable Reference for Penning Trap
Experiments - for the Alphatrap experiment. The Alphatrap experiment
is located at the Max Planck Institute for Nuclear Physics in Heidelberg and
aims to determine the g-factor of bound electrons with high precision to test
quantum electrodynamics in very strong fields. A crucial point for the highprecision
measurements is the determination of the ions’ axial frequency,
for the reason that the axial frequency is necessary to determine one of the
frequencies needed to calculate the g-factor. The axial frequency stability in
turn depends on the stability of the voltage for the Penning-trap electrodes,
which are supplied by the StaReP. To avoid that the temperature stability
of the StaReP is limiting the achievable precision, a temperature stability
better than 10 mK on a time scale of one measurement cycle - in order of
10 minutes - is desirable. Besides that the temperature stabilization should
enable a rapid temperature stabilization, due to the required refilling of the
cryostats. For the fillings the room has to be entered every three to four
days, which causes large temperature fluctuations. A desirable time scale
for the stabilization is given by the time the cryostates need to get into a
steady state due to mechanical expansion and shrinking of the frame. This is
observed to be in the range of one to two hours, the design and comissioning of
this stabilization with a PI-regulator is presented in the following bachelor’s
thesis.