Experiments with Supersonic Beams as a Source of Cold Atoms

Figure 5.3: Photograph of the hydrogen coilgun coil wound around the slowing chamber.
The coils are held in place by Delrin clamps, which are clamped onto the chamber
before the coil is wound.
is 19.5 mm. The overall length of the coil is 7.26 mm. When the coil is pulsed, a peak
current of approximately 825 A flows through the coil, producing peak on axis fields
of 1.4 T. The finite element numerical calculation of the field profile can be seen in
figure 5.2.
The coils are wound around the vacuum chamber and held in place by Delrin
spacers that are clamped to the chamber, as shown in figure 5.3. This allows the
coils to be as close as possible to the atoms without being in vacuum. The Delrin
spacers place the coils 12.45 mm apart center-to-center. This spacing is set by the
wire thickness, as the wire from the inner layer of a coil needs a path to the outside
of the coils. Making the coils much closer together would make it difficult to insert
the inner winding if the adjacent coil is already wound.
5.2.1.2 Slowing Coil Electronics and Switching
Due to the increased size of the coils, the inductance of the hydrogen coilgun
coils is larger than the coils used in the previous coilgun iterations (10 μH instead
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