Dual-Axis Radiographic Hydrodynamic Test Facility: Difference between revisions

Planning for DARHT began in the early 1980s.<ref name=1663news /> [[LawrenceBased Livermoreupon Nationalthe Laboratory]]success inof CaliforniaLivermore’s hadFXR, already developed an advanced electron accelerator for its own xinduction-ray hydrotestlinac facility., Inin 1987 Los Alamos chose the same type of accelerator to replace PHERMEX, an RF accelerator commissioned in 1963.

Construction was halted between 1995 and 1996 due to lawsuits by Los Alamos Study Group and Concerned Citizens for Nuclear Safety, two anti-nuclear weapons organizations demanding that the laboratory produce an [[Environmental Impact Statement]] for its construction and operation. It has also beenActivists argued by activists that DARHT is ain violation of the [[Comprehensive Test Ban Treaty]] and potentially the [[Nuclear Non-Proliferation Treaty]], though the lab and the DOE reject this view.

When completed in 1999, the first-axis accelerator couldproduced producea one short60ns electron pulse lasting 60 ns with a current of 2 kA and an energy of 20 MeV. The beam could be focused to 2-millimeter1mm diameter spot on the target. It was- the smallest spot size and shortest pulse length ever achieved at that intensity.<ref name=1663news /> As a result, image quality was about three times higher than at Livermore's x-rayFXR facility.

The second machine (second axis) is more complicated and, when first completed in 2003, was found to be unusable due to electrical breakdown.<ref>Fleck, John. "Failure of Axis Plagues Labs", ''Albuquerque Journal'' (26 December 2005): A1.</ref> The origin of the electrical breakdown turned out to be unexpectedly high electric fields between the high-voltage plate and the oil-insulated magnetic cores and at sites where metal, high-voltage insulator, and vacuum meet inside the cells. After much analysis, the design error in design was tracked to be due to faulty equipment used when doing voltage calibrations.<ref name=1663news />

An extensive design overhaul and rebuild was required, which was completed in 2008.<ref>{{cite news|title=Los Alamos National Laboratory to Begin DARHT 2 Operations|url=http://www.lanl.gov/news/index.php/fuseaction/home.story/story_id/12451|accessdate=19 September 2010|newspaper=LANL Press Release|date=29 January 2008}}</ref> The project was initially expected to cost $30 million in 1988, but costs ultimately rose to $350 million by 2008 when the facility became completely operational.<ref>[http://www.lanl.gov/news/releases/archive/99-167.shtml Los Alamos' DARHT aces first test] {{webarchive |url=https://web.archive.org/web/20081121011433/http://www.lanl.gov/news/releases/archive/99-167.shtml |date=November 21, 2008 }} November 9, 1999</ref><ref>[http://lanl-the-rest-of-the-story.blogspot.com/2008/05/doe-says-darht-fully-operational.html DOE Says DARHT Fully Operational; Questions Remain] May 26, 2008</ref>