CEBAF beam loss accounting

Ursic, R.; Mahoney, K.; Hovater, C.; Hutton, A.; Sinclair, C. K.

doi:10.1109/pac.1995.505648

Cited by 6 publications

(3 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The threshold for beam loss at which beam operation is terminated has been set to 20% of this value, 5000 pA-pec, with a 2 pA minimum current. To measure this integrated loss, a system based on beam current accounting [4], as opposed to loss monitoring, was instituted. The system uses cavity monitors in the beamlines to measure the beam current at the exit of the injector and the entrances to the experimental halls and other beam dumps; e.g beam switchyard dump.…”

Section: Figurementioning

confidence: 99%

Operating experience at CEBAF

Legg¹

1996

View full text Add to dashboard Cite

Section: Figurementioning

confidence: 99%

Operating experience at CEBAF

Legg¹

1996

View full text Add to dashboard Cite

“…The cavity is a simple pill box cavity, resonating the TM,,lo mode at 1497 MHz. Constructed of stainless steel in order to minimize drifts due to temperature, Q is approximately 3000 and the geometric shunt impedance is 180 S2 [2]. The signal from the cavity is sent to the isochronous measurement chassis as shown in Figure 2 .…”

Section: Path Length / Ms Measuremnt Hardwarementioning

confidence: 99%

Automated path length and M/sub 56/ measurements at Jefferson Lab

Hardy

Tang²,

Legg³

et al.

Proceedings of the 1997 Particle Accelerator Conference (Cat. No.97CH36167)

View full text Add to dashboard Cite

Accurate measurement of path length and path length changes versus momentum (Msa) are critical for maintaining minimum beam energy spread in the CEBAF (Continuous Electron Beam Accelerator Facility) accelerator at the Thomas Jefferson National Accelerator Facility (Jefferson Lab). The relative path length for each circuit of the beam (1256m) must be equal within 1.5 degrees [l] of 1497 M H z RF phase. A relative path length measurement is made by measuring the relative phases of RF signals from a cavity that is separately excited for each pass of a 4.2 ps pulsed beam. This method distinguishes the path length to less than 0.5 degrees of RF (<280 pn) and gives the direction of the path length error. The development of a VME based automated measurement system for path length and M56 has contributed to faster machine setup time and has the potential for use as a feedback parameter for automated control.

show abstract

“…The IF signal is envelopedetected using a true RMS-DC converter, where the output is compared to the other end-station signals and injector signal. Resulting beam loss is integrated, and a fast-shutdown occurs if the integrated loss exceeds a threshold of 5000 µA-µS [1].…”

Section: Beam Current Monitormentioning

confidence: 99%

A DSP-based beam current monitoring system for machine protection using adaptive filtering

Musson

Dong

Flood

et al.

PACS2001. Proceedings of the 2001 Particle Accelerator Conference (Cat. No.01CH37268)

Self Cite

View full text Add to dashboard Cite

The CEBAF accelerator at Jefferson Lab is currently using an analog beam current monitoring (BCM) system for its machine protection system (MPS), which has a loss accuracy of 2 µA. Recent burn-through simulations predict catastrophic beam line component failures below 1 µA of loss, resulting in a blind spot for the MPS. Revised MPS requirements target an ultimate beam loss accuracy of 250 nA. A new beam current monitoring system has been developed which utilizes modern digital receiver technology and digital signal processing concepts. The receiver employs a direct-digital down converter integrated circuit, mated with a Jefferson Lab digital signal processor VME card. Adaptive filtering is used to take advantage of current-dependent burn through rates. Benefits of such a system include elimination of DC offsets, generic algorithm development, extensive filter options, and interfaces to UNIX -based control systems.

show abstract

CEBAF beam loss accounting

Cited by 6 publications

References 0 publications

Operating experience at CEBAF

Operating experience at CEBAF

Automated path length and M/sub 56/ measurements at Jefferson Lab

A DSP-based beam current monitoring system for machine protection using adaptive filtering

Contact Info

Product

Resources

About