| Paper | Title | Page |
|---|---|---|
| WEPC27 | Segmented Foil SEM Grids for High-Intensity Proton Beams at Fermilab | 370 |
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| The extracted beam transport lines and transfer lines between accelerators at Fermilab must operate at ever higher proton fluences to service the neutrino program and the production of antiprotons for the Tevatron collider program. The high proton fluences place stringent criteria on invasive instrumentation to measure proton beam profiles. Based on a design from CERN, we have built SEM's consisting of Ti foils segmented at either 1.0mm or 0.5mm pitch. The foils are 5um thick Titanium, and two planes of the segmented foils per SEM chamber provides both horizontal and vertical beam profiles. The foil SEM's provide several features over the Au-plated 75 um Ø W-wire SEM's previously in use at Fermilab: (1) a factor 50-60 lower fractional beam loss; (2) greater longevity of Ti signal yield, as compared with W or Au-W; (3) a 'bayonnette'-style frame permitting insertion/retraction from the beam without interruption of operations; and (4) reduced calculated beam-heating from the high-intensity proton-pulses, which results in less sag of the wires/foils. Experience with these detectors after two years' operations in 8 and 120GeV beams will be summarized. |