Transport efficiency of the Argonne fragment mass analyzer

• Published in: Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment Accelerators, spectrometers, detectors and associated equipment, 1996-09, Vol.379 (2), p.206-211
• Main Authors: Back, B.B, Blumenthal, D.J, Davids, C.N, Henderson, D.J, Hermann, R.H, Jiang, C.L, Penttilä, H.T, Wuosmaa, A.H
• Format: Article
• Language: English
• ISSN: 0168-9002; 1872-9576
• DOI: 10.1016/0168-9002(96)00650-X

Absolute transmission efficiencies for the Argonne fragment mass analyzer (FMA) have been measured for ions of 184W, 208Pb, and 232Th with energies in the range E = 20–45 MeV. These were obtained by Rutherford scattering of 32S beams of 50, 80 and 100 MeV into backward angles. Measurements were performed for a range of settings for the FMA in order to determine the acceptance of the instrument as a function of energy and angle of the incident ion. The transport efficiency across the focal plane was also measured. The results are compared with predictions of the transport code GIOS [H. Wollnik et al., Nucl. Instr. and Meth. A 258 (1987) 408], which agree well with the data. With these data we conclude that the transport efficiency of the FMA is sufficiently well known to support measurements of absolute cross sections with an accuracy of ±10%.