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USJ-TAX  -  US-Japan Triple Axis Spectrometer

Source and Guide

The cold neutron moderator is the new HB4 supercritical hydrogen moderator (505 ml) and is the brightest source of cold neutrons in the world.

The USJ-TAX will be stationed at port C of cold guide 4 (CG-4C) in HFIR’s new Cold Guide Hall. This guide carries neutrons from a new cold moderator at HFIR’s port HB4. Near the moderator, an 8° bend provides space for our monochromator shield and removes our source from line of sight with respect to HB4’s fast neutrons. This bender has four channels and 90 strait sections in order to preserve reasonable divergence and up to 20 meV neutrons for the spectrometer. The bender also includes a vertical trumpet, which exchanges vertical divergence for a higher guide-beam profile; the 15 cm tall profile for the CG-4 beam is then well exploited by USJ-TAX’s vertically focusing monochromator. The expected flux at sample will place the USJ-TAX within the set of best-in-class cols neutron triple axis spectrometers, worldwide.

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Last Modified: Wednesday, 05-Mar-2008 14:04:47 EST
Please forward all questions about this site to: Barry Winn