The
University of Michigan Spin Physics Center focuses on studies of spin effects in high polarized proton-proton elastic and inelastic scattering. These polarized scattering experiments use the world-class solid and jet polarized proton targets, which are developed, upgraded and tested at the center. The Center obtained a record density of about 10
12 spin-polarized hydrogen atoms per cm
3.
The center also led the development of the world's first accelerated polarized beams at the 12 GeV Argonne
ZGS (in 1973) and then at the 28 GeV Brookhaven
AGS. The Center led pioneering experiments at the IUCF Cooler Ring from 1988 until its 2003 shutdown, which developed and tested
Siberian snakes and
Spin-flippers, which are now used to accelerate, store and use high energy
polarized proton beams.
The center also leads the
International SPIN Collaboration and its proton polarization know-how is used in many experiments worldwide.
Main discoveries
In 1978 the Center found that protons with parallel spins interact much stronger than protons with anti-parallel spin.
According to
Quantum Chromodynamics the interaction between parallel and anti-parallel spinning proton beams should be the same.
Sheldon Glashow
Sheldon Lee Glashow (, ; born December 5, 1932) is a Nobel Prize-winning American theoretical physicist. He is the Metcalf Professor of Mathematics and Physics at Boston University and Eugene Higgins Professor of Physics, Emeritus, at Harvard U ...
called this effect "the thorn in the side of QCD".
This effect remained unexplained until today. In 2005
Stanley Brodsky called it "one of the unsolved mysteries in hadronic physics".
References
{{Reflist
External links
Michigan Spin Physics Center
Quantum chromodynamics
Particle experiments
Unsolved problems in physics
University of Michigan