The principal accelerator used in this laboratory for materials analysis is an RPEA 4.0 Dynamitron. This accelerator was purchased from Radiation Dynamics, Inc. in 1965. Since that time, it has been extensively updated to remain abreast of current technology.
The Dynamitron uses an all-electronic power supply, which allows rapid and easy computer control for any voltage from 0.3 MeV to 4.0 MeV. This normally allows particle energies in the same range. In addition, by using doubly charged ions, the energy range can be extended to 8.0 MeV. The user can choose either mode merely by changing a setting in the computer. The doubly-charged mode gives a much weaker beam, and is therefore not used for energies below 4.0 MeV.
Six beamlines are installed with the Dynamitron. Each one is designed for a somewhat different class of operation.
The 20 beamline is dedicated to ion implantation. Ions currently available are listed below.
The 30 beamline has a seven-sample target wheel and is equipped for RBS and NRA.
The 45 beamline has two principal sample holders. The single-sample goniometer is intended for channeling measurements. The ten-sample wheel is intended for general-purpose measurement. The chamber is equipped for simultaneous RBS and PIXE measurements.
The 60 beamline has a UHV surface studies chamber equipped for RBS.
The 70 beamline is dedicated to the HIRRBS facility for high-resolution RBS measurements.
The 90 beamline is dedicated to the Microbeam facility, which can place a 1-micron diameter beam anywhere on the sample and can analyze samples using simultaneous RBS and PIXE.
DYNAMITRON OPERATING LIMITS
ABSOLUTE VOLTAGE LIMIT --- 4.5 MV
PRACTICAL VOLTAGE LIMIT -- 4.0 MV
MASS-ENERGY PRODUCT LIMITS
||M-E PRODUCT LIMIT
||EXAMPLE UPPER LIMIT
||Xe-134 at 4.0 MeV
||Kr -84 at 1.9 MeV
||Ar -40 at 2.7 MeV
||Ne-20 at 2.7 MeV
||O -16 at 2.18 MeV
||He- 4 at 4 MeV
SOURCE IONS AVAILABLE