RESULTS FROM THE COMMISSIONING OF THE NSRL BEAM TRANSFER LINE AT BNL

The NASA SPACE RADIATION LABORATORY (NSRL) has been constructed and started operations at the Brookhaven National Laboratory in 2003. The NSRL facility will be used by NASA to perform radiation effect studies on materials and biological samples for the space program. The facility utilizes proton and heavy-ion beams of energies from 50 to 3000 MeV/n which are accelerated by the AGS_Booster synchrotron accelerator. To date, 1H, 12 C, 56 Fe, 48 Ti, and 197 Au ion beams of various magnetic rigidities have been extracted from the Booster, and transported by the NSRL beam transport line to the sample location which is located 100 m from the extraction point. The NSRL beam transport line has been designed to employ octupole magnetic elements (1) which transform the normal (Gaussian) beam distribution at the location of the sample into a beam with rectangular cross section, and with uniform distribution over the sample. When using the octupole magnetic elements to obtain the uniform beam distribution on the sample, no beam- collimation is applied at any location along the NSRL beam transport line and the beam focusing on the sample is purely magnetic. The main subject of this paper will be the performance of the octupoles (third order optics) in obtaining uniform beam distributions at the target location of the NSRL beam transport line.