Magnetic Field and Beam Dynamics Calculations for SUSE
The SuSe magnet system is designed using the program GFUN3D. A small version of this program was connected to a general fit program by means of which the current in the main and trim coils was determined for a given isochronous mean field B¿(r). For beam dynamics calculations with the code GOC accurate fields (¿B¿/B¿ ¿ 1%) were used which were obtained by means of the program GFUN400 where the unique part of the magnet iron is subdivided into 400 elements at maximum. Several coil systems have been investigated. In an alternative design all coils have straigth sections which are easier to manufacture than coils with negative curvature. The main coils have a largest radial extension of 3.08 m. There are 22 correcting coils inside each main coil.
Magnetic field optimization and beam dynamics calculations for SuSe
The superconducting sector magnets of SuSe have been designed using the newly developed program GFUNFIT. By means of this program the deviation of the desired magnetic field from the actual value, which is produced by the magnetic system, can be minimized to within 0.5 Gauss by variation of several parameters, such as conductor current, geometry of conductors and of iron. Varying these parameters, fields with an absolute accuracy of ΔB/B ≲ 1 % have been obtained using the finite-element programs GFUN3D and GETM400. The code GOC has been used to study the beam dynamics in these fields. Two examples for fully stripped heavy ions (q/A = 0.5) with maximum and half maximum final energies (T2/A = 300 MeV/n and 150 MeV/n) are given.
Anomalous Annealing Behavior of Arsenic Implanted Silicon as a Function of Dose and Energy
Anomalous annealing behavior of damage in As implanted Si has been investigated by channeling effect measurements. Room temperature As implants with doses from 1014 to 2 × 1016cm-2 at energies ranging from 50 to 250 keV into Si were annealed over the range of 600°C to 1100°C. Anneal temperatures ≥ 950°C reduce the disorder for ion doses of 0.5 to 1 × 1016 cm-2 at energies between 50 and 250 keV. Anomalously high residual disorder was found for the intermediate doses of 2 × 1014 to 2 × 10/cm2 implanted above 100 keV. For this intermediate dose, annealing of implants performed at liquid nitrogen temperatures did not show significant reduction in this damage. However implants at 200° to 300°C indicate a lower amount of damage compared to the room temperature implants.