A method of obtaining parasitic e/sup +/ or e/sup -/ beams during SLAC linear collider operation

We have developed a technique that allows SLAC to provide parasitic low-intensity secondary e/sup +/ and e/sup -/ beams up to 25 GeV to End Stations A and B and to the FFTB during SLC operation. This beam was successfully used for a one-month-long experimental run in End Station A by the SLAC E146 collaboration. The experiment used 400 MeV to 25 GeV electron beams at intensities averaging one electron per pulse and 120 pulses per second. The method for producing such a beam without the need for dedicated beam time was to operate parasitically from SLC: photons produced in the SLC beam scrapers in linac sectors 28, 29 and 30 were converted to positrons and electrons in a target downstream from the SLC splitter magnet. The secondary electrons or positrons were then transported to ESA with the A-line.<
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