SPIN@U-70: An Experiment to Measure the Analyzing Power An in Very-high-P[sub ⊥][sup 2] p-p Elastic Scattering at 70 GeV.

The SPIN@U-70 experiment plans to measure the one-spin analyzing power An for 70 GeV proton-proton elastic scattering at large P[sub ⊥][sup 2] values of 1 to 12 (GeV/c)2. The Michigan frozen NH3 polarized proton target (Solid PPT) should later be installed in the Channel 8 extracted beam-line of the 70 GeV U-70 accelerator in IHEP, Protvino. The forward-scattered protons are detected by small scintillation counters placed at about 9 m from the PPT, while the recoil-scattered protons are detected by a 35-m-long focusing magnetic spectrometer, with a 12 degree vertical bend, placed at 30 degrees to the beam. A tune-up run for testing the beam and the spectrometer, using a polyethylene target, was carried out in April 2002 at IHEP. The layout and the results of the test run are presented. © 2003 American Institute of Physics [ABSTRACT FROM AUTHOR]