Hard Collisions of Spinning Protons - History and Future

TL;DR

This paper reviews the history of polarized proton beams, discusses unexplained large transverse spin effects observed in high energy experiments, and explores future experimental prospects at international accelerators.

Contribution

It provides a comprehensive overview of past findings and discusses potential future experiments on polarized proton collisions at high energies.

Findings

Large transverse spin effects observed in experiments remain unexplained.

Historical development of polarized proton beam technology.

Future experiments planned at U-70 and J-PARC accelerators.

Abstract

There will be a review of the history of polarized proton beams, and a discussion of the unexpected and still unexplained large transverse spin effects found in several high energy proton-proton spin experiments at the ZGS, AGS, Fermilab and RHIC. Next there will be a discussion of possible future experiments on the violent collisions elastic collisions of polarized protons at the 70 GeV U-70 accelerator at IHEP-Protvino in Russia and the new high intensity 50 GeV J-PARC at Tokai in Japan.