Noise Reduction and Correction in the IPNS Linac ESEM
- Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439 (United States)
The Energy Spread and Energy Monitor (ESEM) is an on-line, non-intrusive diagnostic used to characterize the output beam from the 200-MHz, 50-MeV IPNS linac. The energy spread is determined from a 3-size, longitudinal emittance measurement; whereas the energy is derived from time of flight (TOF) analysis. Signals are detected on 50-ohm, stripline beam position monitors (BPMs) terminated in their characteristic impedance. Each BPM is constructed with four striplines: top, bottom, left and right. The ESEM signals are taken from the bottom stripline in four separate BPM locations in the 50-MeV transport line between the linac and the synchrotron. Deterministic linac noise is sampled before and after the 70-microsecond macropulse. The noise phasor is vectorially subtracted from the beam signal. Noise subtraction is required at several frequencies, especially the fundamental and fifth harmonics (200 MHz and 1 GHz). It is also necessary to correct for attenuation and dispersion in the co-axial signal cables. Presently, the analysis assumes a single particle distribution to determine energy and energy spread. Work is on-going to allow for more realistic longitudinal distributions to be included in the analysis.
- OSTI ID:
- 20630279
- Journal Information:
- AIP Conference Proceedings, Vol. 732, Issue 1; Conference: 11. beam instrumentation workshop, Knoxville, TN (United States), 3-6 May 2004; Other Information: DOI: 10.1063/1.1831155; (c) 2004 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
Similar Records
Vertical Instability at IPNS RCS.
Diagnostic and numerical studies of the IPNS LINAC with a recently installed buncher amplifier.