Shielded capacitive electrode
Abstract
A device is described, which is sensitive to electric fields, but is insensitive to stray electrons/ions and unlike a bare, exposed conductor, it measures capacitively coupled current while rejecting currents due to charged particle collected or emitted. A charged particle beam establishes an electric field inside the beam pipe. A grounded metallic box with an aperture is placed in a drift region near the beam tube radius. The produced electric field that crosses the aperture generates a fringe field that terminates in the back surface of the front of the box and induces an image charge. An electrode is placed inside the grounded box and near the aperture, where the fringe fields terminate, in order to couple with the beam. The electrode is negatively biased to suppress collection of electrons and is protected behind the front of the box, so the beam halo cannot directly hit the electrode and produce electrons. The measured signal shows the net potential (positive ion beam plus negative electrons) variation with time, as it shall be observed from the beam pipe wall.
- Inventors:
- Issue Date:
- Research Org.:
- Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1088292
- Patent Number(s):
- 8481961
- Application Number:
- 12/368,541
- Assignee:
- The Regents of the University of California (Oakland, CA)
- Patent Classifications (CPCs):
-
G - PHYSICS G01 - MEASURING G01R - MEASURING ELECTRIC VARIABLES
G - PHYSICS G21 - NUCLEAR PHYSICS G21K - TECHNIQUES FOR HANDLING PARTICLES OR IONISING RADIATION NOT OTHERWISE PROVIDED FOR
- DOE Contract Number:
- AC02-05CH11231
- Resource Type:
- Patent
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 42 ENGINEERING; 43 PARTICLE ACCELERATORS
Citation Formats
Kireeff Covo, Michel. Shielded capacitive electrode. United States: N. p., 2013.
Web.
Kireeff Covo, Michel. Shielded capacitive electrode. United States.
Kireeff Covo, Michel. Tue .
"Shielded capacitive electrode". United States. https://www.osti.gov/servlets/purl/1088292.
@article{osti_1088292,
title = {Shielded capacitive electrode},
author = {Kireeff Covo, Michel},
abstractNote = {A device is described, which is sensitive to electric fields, but is insensitive to stray electrons/ions and unlike a bare, exposed conductor, it measures capacitively coupled current while rejecting currents due to charged particle collected or emitted. A charged particle beam establishes an electric field inside the beam pipe. A grounded metallic box with an aperture is placed in a drift region near the beam tube radius. The produced electric field that crosses the aperture generates a fringe field that terminates in the back surface of the front of the box and induces an image charge. An electrode is placed inside the grounded box and near the aperture, where the fringe fields terminate, in order to couple with the beam. The electrode is negatively biased to suppress collection of electrons and is protected behind the front of the box, so the beam halo cannot directly hit the electrode and produce electrons. The measured signal shows the net potential (positive ion beam plus negative electrons) variation with time, as it shall be observed from the beam pipe wall.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Jul 09 00:00:00 EDT 2013},
month = {Tue Jul 09 00:00:00 EDT 2013}
}