Measurement of the real part of the K/sup -/p elastic scattering amplitude at 10 GeV/c

Bubble chamber film of 10 GeV/c K/sup -/p interactions was scanned automatically by an H.P.D to look for small angle scatters in the mod t mod -range from 0.008 to 0.1 GeV/sup 2/. Combining the 1800 events so obtained with 22000 elastic events obtained from normal scanning ( mod t mod >0.06 GeV/sup 2/), the real part of the elastic scattering amplitude was found to be (+25+or-10)% of the imaginary part. Evidence is found for a change in slope in the differential cross-section distribution, from 9.8+or-0.6 GeV/sup -2/ in the mod t mod -range below 0.1 GeV/sup 2/ to 7.1+or-0.2 GeV/sup -2/ in the range 0.12< mod t mod <or=0.4 GeV/sup 2/. (19 refs)