Accession Number : ADA257983
Title : Identification of Toroidal Field Errors in a Modified Betatron Accelerator
Descriptive Note : Interim rept.
Corporate Author : NAVAL RESEARCH LAB WASHINGTON DC
Personal Author(s) : Loschialpo, P ; Kapetanakos, C A ; Marsh, S J ; Len, L K ; Smith, T
Report Date : Nov 1992
Pagination or Media Count : 26
Abstract : A newly developed probe has been used to detect errors in the toroidal magnetic field of the NRL modified betatron accelerator. Measurements indicate that the radial field components (errors) are 0.1 to 1% of the applied toroidal field. Such errors, in the typically 5 kG toroidal field, can excite resonances which drive the beam to the wall. Two sources of detected field errors are discussed. The first is due to the discrete nature of the twelve single turn coils which generate the toroidal field. Measurements and computer calculations indicate that it's amplitude varies from 0 to 0.2% as a function of radius. This error is a good suspect for causing the excitation of the damaging l approx. 12 resonance seen in our experiments. The other source of field error is due to the current feed gaps in the vertical magnetic field coils. A magnetic field is induced inside the vertical field coils' conductor in the opposite direction of the applied toroidal fields. Fringe fields at the gaps lead to additional field errors which have been measured as large as 1.0%. Field errors measurements.
Descriptors : *MAGNETIC FIELDS , *BETATRONS , FUNCTIONS , MEASUREMENT , COMPUTERS , RESONANCE , DRIVES , AMPLITUDE , WALLS , ERRORS , EXCITATION , PROBES , COILS
Subject Categories : Electricity and Magnetism
Distribution Statement : APPROVED FOR PUBLIC RELEASE