Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude
Abstract
A beam current limiter for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region.more »
- Inventors:
-
- Lombard, IL
- Park Forest, IL
- Downers Grove, IL
- Issue Date:
- Research Org.:
- Argonne National Laboratory (ANL), Argonne, IL (United States)
- OSTI Identifier:
- 870016
- Patent Number(s):
- 5440210
- Assignee:
- University of Chicago (Chicago, IL)
- Patent Classifications (CPCs):
-
A - HUMAN NECESSITIES A61 - MEDICAL OR VETERINARY SCIENCE A61B - DIAGNOSIS
G - PHYSICS G01 - MEASURING G01R - MEASURING ELECTRIC VARIABLES
- DOE Contract Number:
- W-31109-ENG-38
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- indirectly; sensing; accelerator; beam; currents; limiting; maximum; current; magnitude; limiter; particle; cyclotron; linear; scientific; medical; treatment; pair; independently; operable; capacitive; electrodes; sense; passage; charged; bunches; rf; signal; indicative; produced; output; bunched; electrode; converted; variable; dc; voltage; voltages; developed; compared; verify; proper; function; references; detect; excess; pre-established; limits; event; malfunction; detected; exceeds; automatically; inhibits; operation; tank; circuit; associated; provides; narrow; bandwidth; reduce; noise; enhance; dynamic; range; linearity; provided; injecting; offset; bunching; frequency; pre-determined; beat; ensure; subsequent; rectifying; diodes; operate; response; region; combination; accelerator beam; tank circuit; independently operable; beam current; particle accelerator; rf signal; beam accelerator; dynamic range; charged particle; dc voltage; linear accelerator; signal indicative; beat frequency; current limiter; sensing electrode; signal produced; beam currents; electrode provides; current magnitude; dc voltages; particle accelera; directly sensing; linear response; current limit; /315/348/
Citation Formats
Bogaty, John M, Clifft, Benny E, and Bollinger, Lowell M. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude. United States: N. p., 1995.
Web.
Bogaty, John M, Clifft, Benny E, & Bollinger, Lowell M. Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude. United States.
Bogaty, John M, Clifft, Benny E, and Bollinger, Lowell M. Sun .
"Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude". United States. https://www.osti.gov/servlets/purl/870016.
@article{osti_870016,
title = {Indirectly sensing accelerator beam currents for limiting maximum beam current magnitude},
author = {Bogaty, John M and Clifft, Benny E and Bollinger, Lowell M},
abstractNote = {A beam current limiter for sensing and limiting the beam current in a particle accelerator, such as a cyclotron or linear accelerator, used in scientific research and medical treatment. A pair of independently operable capacitive electrodes sense the passage of charged particle bunches to develop an RF signal indicative of the beam current magnitude produced at the output of a bunched beam accelerator. The RF signal produced by each sensing electrode is converted to a variable DC voltage indicative of the beam current magnitude. The variable DC voltages thus developed are compared to each other to verify proper system function and are further compared to known references to detect beam currents in excess of pre-established limits. In the event of a system malfunction, or if the detected beam current exceeds pre-established limits, the beam current limiter automatically inhibits further accelerator operation. A high Q tank circuit associated with each sensing electrode provides a narrow system bandwidth to reduce noise and enhance dynamic range. System linearity is provided by injecting, into each sensing electrode, an RF signal that is offset from the bunching frequency by a pre-determined beat frequency to ensure that subsequent rectifying diodes operate in a linear response region. The system thus provides a large dynamic range in combination with good linearity.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 1995},
month = {Sun Jan 01 00:00:00 EST 1995}
}