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Title: The design and initial testing of a beam phase and energy measurement for LEDA

Journal Article · · AIP Conference Proceedings
DOI:https://doi.org/10.1063/1.57053· OSTI ID:344473
;  [1]
  1. Los Alamos National Laboratory Los Alamos, New Maxico 87545 (United States)

A diagnostic system being designed to measure the beam phase and beam energy of the Low Energy Demonstration Accelerator (LEDA) is described and the characterization of the prototype presented. The accelerator, being built at LANL, is a 350 MHz proton linac with a 100 mA beam. In the first beam experiments, the 6.7 MeV RFQ will be characterized. Signals received from an rf cavity probe in the RFQ and capacitive pick-ups along the high-energy beam transport line will be compared in phase in order to calculate the beam phase and energy. The 350 MHz signals from four pick-ups will be converted to 2 MHz in a VXI-based down converter module. A second VXI phase processor module makes two, differential-phase measurements based on its four 2 MHz inputs. The heart of this system is the phase processor module. The phase processor consists of an analog front end (AFE), digital front end (DFE), digital signal processing (DSP) modules and the VXI bus interface. The AFE has an AGC circuit with a {gt}60 dB dynamic range with a few degrees of phase shift. Following the AFE is the DFE which uses an in-phase and quadrature-phase (I and Q) technique to make the phase measurement. The DSP is used to correct the real-time data for phase variations as a function of dynamic range and system offsets. The prototype phase module gives an absolute accuracy of {plus_minus}0.5 degrees with a resolution of {lt}0.1 degrees and a bandwidth of 200 kHz. {copyright} {ital 1998 American Institute of Physics.}

Sponsoring Organization:
USDOE
OSTI ID:
344473
Report Number(s):
CONF-980573-; ISSN 0094-243X; TRN: 99:005673
Journal Information:
AIP Conference Proceedings, Vol. 451, Issue 1; Conference: 8. beam instrumentation workshop (BIW-98), Stanford, CA (United States), 4-7 May 1998; Other Information: PBD: Dec 1998
Country of Publication:
United States
Language:
English