Experimental evaluation of a negative ion source for a heavy ionfusion negative ion driver

PDF Version Also Available for Download.

Description

Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photodetached to neutrals [1,2,3]. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 … continued below

Creation Information

Grisham, L. R.; Hahto, S. K.; Hahto, S. T.; Kwan, J. W. & Leung, K. N. January 18, 2005.

Context

This article is part of the collection entitled: Office of Scientific & Technical Information Technical Reports and was provided by the UNT Libraries Government Documents Department to the UNT Digital Library, a digital repository hosted by the UNT Libraries. It has been viewed 14 times. More information about this article can be viewed below.

Who

People and organizations associated with either the creation of this article or its content.

Sponsor

Publisher

Provided By

UNT Libraries Government Documents Department

Serving as both a federal and a state depository library, the UNT Libraries Government Documents Department maintains millions of items in a variety of formats. The department is a member of the FDLP Content Partnerships Program and an Affiliated Archive of the National Archives.

Contact Us

What

Descriptive information to help identify this article. Follow the links below to find similar items on the Digital Library.

Description

Negative halogen ions have recently been proposed as a possible alternative to positive ions for heavy ion fusion drivers because electron accumulation would not be a problem in the accelerator, and if desired, the beams could be photodetached to neutrals [1,2,3]. To test the ability to make suitable quality beams, an experiment was conducted at Lawrence Berkeley National Laboratory using chlorine in an RF-driven ion source. Without introducing any cesium (which is required to enhance negative ion production in hydrogen ion sources) a negative chlorine current density of 45 mA/cm{sup 2} was obtained under the same conditions that gave 57 mA/cm{sup 2} of positive chlorine, suggesting the presence of nearly as many negative ions as positive ions in the plasma near the extraction plane. The negative ion spectrum was 99.5% atomic chlorine ions, with only 0.5% molecular chlorine, and essentially no impurities. Although this experiment did not incorporate the type of electron suppression technology that is used in negative hydrogen beam extraction, the ratio of co-extracted electrons to Cl{sup -} was as low as 7 to 1, many times lower than the ratio of their mobilities, suggesting that few electrons are present in the near-extractor plasma. This, along with the near-equivalence of the positive and negative ion currents, suggests that the plasma in this region was mostly an ion-ion plasma. The negative chlorine current density was relatively insensitive to pressure, and scaled linearly with RF power. If this linear scaling continues to hold at higher RF powers, it should permit current densities of 100 mA/cm{sup 2}, sufficient for present heavy ion fusion injector concepts. The effective ion temperatures of the positive and negative ions appeared to be similar and relatively low for a plasma source.

Source

  • 15th International Symposiuson Heavy Ion Fusion,Princeton, NJ, 06/7-11/ 2004

Language

Item Type

Identifier

Unique identifying numbers for this article in the Digital Library or other systems.

  • Report No.: LBNL--56914
  • Report No.: HIFAN 1387
  • Grant Number: DE-AC02-05CH11231
  • Office of Scientific & Technical Information Report Number: 861590
  • Archival Resource Key: ark:/67531/metadc794201

Collections

This article is part of the following collection of related materials.

Office of Scientific & Technical Information Technical Reports

Reports, articles and other documents harvested from the Office of Scientific and Technical Information.

Office of Scientific and Technical Information (OSTI) is the Department of Energy (DOE) office that collects, preserves, and disseminates DOE-sponsored research and development (R&D) results that are the outcomes of R&D projects or other funded activities at DOE labs and facilities nationwide and grantees at universities and other institutions.

What responsibilities do I have when using this article?

When

Dates and time periods associated with this article.

Creation Date

  • January 18, 2005

Added to The UNT Digital Library

  • Dec. 19, 2015, 7:14 p.m.

Description Last Updated

  • Dec. 6, 2017, 4:14 p.m.

Usage Statistics

When was this article last used?

Yesterday: 0
Past 30 days: 0
Total Uses: 14

Interact With This Article

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Grisham, L. R.; Hahto, S. K.; Hahto, S. T.; Kwan, J. W. & Leung, K. N. Experimental evaluation of a negative ion source for a heavy ionfusion negative ion driver, article, January 18, 2005; Berkeley, California. (https://digital.library.unt.edu/ark:/67531/metadc794201/: accessed July 16, 2024), University of North Texas Libraries, UNT Digital Library, https://digital.library.unt.edu; crediting UNT Libraries Government Documents Department.

Back to Top of Screen