50/spl times/50 GeV /spl mu//sup +//spl mu//sup -/ collider beam collimation

A summary of different techniques and systems to scrape beam halo in a 50/spl times/50 GeV /spl mu//sup +//spl mu//sup -/-collider is presented. Such systems are installed in a special utility section with optics specifically designed to meet both the requirements of the scraping system and of injection. Results from a realistic Monte Carlo simulation (STRUCT-MARS) show that a system consisting of steel absorbers several meters in length suppresses halo-induced backgrounds in the collider detector by more than three orders of magnitude. The heat load in superconducting magnets near the scraper system can be reduced to tolerable levels by appropriate collimator design and location. This reduction applies to both injection and collider mode of operation. Also discussed is extraction of halo particles using electrostatic deflectors and bent crystals, although neither appears to be effective for a muon collider at this energy.