Editing Inertial electrostatic confinement (section)

===Marble===

<!-- Deleted image removed: [[File:The multipole Ion-beam experiment magnet.png|thumbnail|The electromagnet used in the MIX system]] -->
MARBLE (multiple [[non-neutral plasma|ambipolar]] recirculating beam line experiment) was a device which moved electrons and ions back and forth in a line.<ref name="AlexPoster">"The Multiple Ambipolar Recirculating Beam Line Experiment" Poster presentation, 2011 US-Japan IEC conference, Dr. Alex Klein</ref> Particle beams were reflected using [[electrostatic lens|electrostatic optics]].<ref>"Dynamics of Ions in an Electrostatic Ion Beam Trap", http://www.weizmann.ac.il/conferences/frisno8/presentations05/thursday/Zajfman.pdf {{Webarchive|url=https://web.archive.org/web/20140108011658/http://www.weizmann.ac.il/conferences/frisno8/presentations05/thursday/Zajfman.pdf |date=2014-01-08}} Presentation, [[Daniel Zajfman]]</ref> These optics made static voltage surfaces in free space.{{citation needed|date=January 2014}} Such surfaces reflect only particles with a specific kinetic energy, while higher-energy particles can traverse these surfaces unimpeded, although not unaffected. Electron trapping and plasma behavior was measured by [[Langmuir probe]].<ref name="AlexPoster"/> Marble kept ions on orbits that do not intersect grid wires—the latter also improves the space charge limitations by multiple nesting of ion beams at several energies.<ref>{{cite web |title=Our Technology |website=Beam Fusion |url=http://www.beamfusion.org/technology/index.html |url-status=dead |archive-url=https://web.archive.org/web/20130406024952/http://www.beamfusion.org/technology/index.html |archive-date=2013-04-06}}</ref> Researchers encountered problems with ion losses at the reflection points. Ions slowed down when turning, spending much time there, leading to high [[electrical conductor|conduction]] losses.<ref>Alex Klein, in person interview, April 30, 2013</ref>