North-American MP tandem accelerators

2014 The North-American MP Tandem accelerators are six in number. Serial § 1. Yale; § 2. Minnesota; § 3. Chalk river; § 4. Rochester; and § 6 and § 7. Brookhaven. The current status and operating characteristics of these six tandem accelerators will be discussed in the order of their serial numbers. Upgrade and special improvements of the different machines will be reviewed and new developments since the last Electrostatic Conference will be discussed in detail. The overall operating characteristics of the different machines during the last year of operation will be compared. REVUE DE PHYSIQUE APPLIQUÉE TOME 12, OCTOBRE 1977, PAGE The Second International Conference on Electrostatic Accelerator Technology will review the improvements and progress in accelerator technology since the first conference held four years ago [1 ]. At the time of the first conference only a few of the MP accelerators had been upgraded with the new large diameter stainless steel acceleration tubes and relatively limited experience had been obtained at that time with these tubes in the different laboratories, with the exception of Chalk River which had the first such installation. Previous to this upgrade capability all of the MP accelerators were operating with aluminium electrode acceleration tubes and the performance was limited to the 8-10 MV region because of breakdown difficulties with this type of tube. Now, four years later, we can report that most of the North-American MP’s that have been upgraded in one way or another are operating at voltages in the vicinity of 12-13 MV on a routine basis for their associated research programs. A number of improvements and innovations have also been developed over the last four years and have contributed to improved performance and ease of operation of these accelerators as well. Some of the improvements discussed in this paper were also reported in the special issue of Nucl. Instrum Methods edited by D. A. Bromley [2]. (*) Work supported by the U.S. Energy Research and Development Administration. By serial number, the North-American MP machines are as follows : § 1. Yale University; § 2. University of Minnesota; § 3. Chalk River Laboratories in Canada; § 4. University of Rochester; and § 6 and § 7. Brookhaven National Laboratory. My review of the current operating characteristics of these machines and the various improvements in design and capability carried out over the last four-year interval will be in the order of their serial numbers. 1. The MP tandem accelerator at Yale University [3] (1). The Yale MP-1 tandem accelerator was the first of the MP machines to change from the , conventional charging belt to the NEC-developed pelletron chain-charging system [4]. Typical charging currents at 13 MV operation are reported to be 260 03BCA of charging current shared between the low and high energy resistor strings, 80 03BCA each, the control corona, 40 03BCA and 60 03BCA of losses associated with a 4 curie 13’Cs radiation source. At present the charging current appears to be limited to a maximum of 400 )lA with the six chaid pelletron system. The accelerator has also been upgraded with the large diameter stainless steel acceleration tubes [5] and the special so-called blue resistors [6] which are part of the standard upgrade kit provided by the High Voltage Engineering Corporation. They have installed (1) P. D. Parker, private communication. Article published online by EDP Sciences and available at http://dx.doi.org/10.1051/rphysap:0197700120100129100