  A high energy beam absorber has been built for the Advanced Superconducting
Test Accelerator (ASTA) at Fermilab. In the facility's initial configuration,
an electron beam will be accelerated through 3 TTF-type or ILC-type RF
cryomodules to an energy of 750MeV. The electron beam will be directed to one
of multiple downstream experimental and diagnostic beam lines and then
deposited in one of two beam absorbers. The facility is designed to accommodate
up to 6 cryomodules, which would produce a 75kW beam at 1.5GeV; this is the
driving design condition for the beam absorbers. The beam absorbers consist of
water-cooled graphite, aluminum and copper layers contained in a Helium-filled
enclosure. This paper describes the mechanical implementation of the beam
absorbers, with a focus on thermal design and analysis. In addition, the
potential for radiation-induced degradation of the graphite is discussed.
