A system for mitigating a gas load imposed upon a high vacuum chamber,
thereby reducing the overall pressure, includes a device mounted onto a
rotating gantry. The device has a first chamber enclosing a high vacuum
and a first region in which anode bearings are positioned. A rotatable
shaft has a first portion extending into the first chamber and a second
portion extending into the first region. A ferrofluid seal is positioned
about the rotatable shaft and positioned between the first portion and
the second portion, the ferrofluid seal fluidically separating the first
chamber from the first region. At least one pressure-reducing unit is
fluidically connected to the first chamber.