E. Tsyganov et A. Taratin, BEAM HALO CRYSTAL EXTRACTION FROM THE TEVATRON DURING COLLIDER RUNS, Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment, 363(3), 1995, pp. 511-519
We have shown by the computer simulation how to extract 1-TeV beam hal
o protons from the Tevatron using a bent crystal. More than 10(7) prot
ons per second, now lost on scrapers and collimators, can be extracted
in a ''passive'' mode, without interference with colliding beam exper
iments. This would reduce background in the colliding beam detectors.
The problem of an existing imperfect layer at a bent crystal surface i
s solved by means of a thin crystal that is used as a crystal mirror f
or beam halo particles. The extraction efficiency can be as large as 9
9%. The availability of an extracted beam will enhance detector R&D st
udies at Fermilab and give an additional boost to the U.S. participati
on in the LHC experiments. As a second priority, small fixed target ex
periments could be carried out. Crystal scrapers-deflectors would also
work well for the LHC where background radiation due to a beam halo l
oss could be reduced by the factor of 100.