Slits

For a variety of applications involving the control of ion beam size and current, NEC manufacture three basic models of slits systems, with variations of each model.  Each model varies in beam power capabilities and geometries.

Applications
NEC slits are ideal for applications requiring accurate control of beam size, determination of beam divergence, or limiting beam current.  NEC’s slits are designed for use on injection and high energy beamlines of medium to high current or high energy electrostatic accelerators.

Design
The slit element assemblies utilize all metal seals to the slit housing and motion is transmitted to the elements through stainless steel welded bellows.  The beam aperture material and the slit elements are either molybdenum or tantalum.  This greatly limits neutron production from light ion beams while providing high temperature tolerance.  Custom element materials are also available upon request.

There are three models of slits, with various versions of each model.  Below is a brief description of each model.

Model Beam Power Rating Maximum aperture Features
BDS6 1000W per element 1.5″ (3.8cm)
  • For use on high energy beamlines of high current or high energy electrostatic accelerators
  • de-ionized water cooling
  • Molybdenum slit elements (tantalum elements optional)
  • elements are cylindrical in cross section to provide maximum cooling
BDS6, double axis (4-jaw)
BDS8 50W per element
(100W optional)
1.2″ (3.0cm)
  • For use on high energy beamlines of medium current electrostatic accelerators and on injector beamlines of large electrostatic accelerators
  • Radiation cooling
  • Tantalum elements
  • beveled edge element design to minimize slit edge scatter (other element designs available)
BDS8, double axis (4-jaw), manual
BDS18 50W per element
(100W optional)
2.0″ (5.1cm)
  • For use on high energy beamlines of medium current electrostatic accelerators and on injector beamlines of large electrostatic accelerators
  • Larger range of adjustment than BDS8 with even larger ranges available upon request
  • Radiation cooling
  • Tantalum elements
  • beveled edge element design to minimize slit edge scatter (other element designs available)
BDS18, double axis (4-jaw), motorized

Options
All three models are available in manual or motorized versions.  They are all available as either single axis (2-jaw) or double axis (4-jaw).

Several slit element options are also available.  The standard BDS8 utilizes a beveled edge element design.  This design minimizes slit edge scattering of the ion beam and is the best element configuration for beam energy control.  However, the elements can also have a folded design or square edge design.  Please contact NEC for more information regarding these options or on element options for the BDS6 and BDS18.

Accessories
For manual slits, we offer a slit current monitor to monitor up to three different slit assemblies.

For a complete motorized slit system, a slit, controller, and logarithmic amplifiers are needed.  We offer both local and remote controllers and a complete line of dual channel log amps. Please contact us for information regarding control of the BDS18.


Related Documents
Slits v1.pdf
Slit Cont v1.pdf