The Cryogenic Electron Beam Ion Source (Cryebis) is a plasma
device designed to generate very highly-charged ions at low velocity.
This makes it an excellent complement to the larger high-velocity
machines in the laboratory, the
Tandem and the
Linac .
Cryebis consists of an electron gun that fires a space-charge-limited
beam down the bore of a high-field superconducting solenoid. The solenoidal
field acts to compress the electrons into the flow regime known as
"Brillouin flow". Arrayed around the beam, down the bore of the solenoid
are sets of cylindrical electrodes. Collisionally ionized atoms are trapped
radially by the space-charge of the electron beam and axially by
the fields put on the electrodes. Continuous bombardment of the
trapped ions results in high charge states. When the ions have
"cooked" enough, the fields on the electrodes can be ramped to expel
them. The ions are magnetically analyzed and directed through a
beamline switchyard to experiments.
One of those beamlines can intersect with another from the
ECR
source and allow unique studies of ion-ion collisions.
Together, the EBIS and ECR constitute the JRM Low Energy Ion Collision Facility (LEICF).
A tutorial on Cryebis operations was created
as part of our contribution to
the APS Centennial celebration in March 1999.
A paper is available
(
pdf,
ps
)
on the newest improvements made to the Cryebis.
The Cryebis/LEICF project is managed by
Charles Fehrenbach.