by Dr Michael Albrow (Fermilab)
In some high-energy proton-proton collisions, the colliding protons are both scattered through small angles with little (at most a few %) energy loss, and a simple state is produced in the central region. "Exclusive" means that the central state is fully specified and measured; there are then limitations on its possible quantum numbers. Examples range from pi+pi- and K+K- production for glueball searches at the ISR, gamma->e+e-, mu+mu- (QED), photo-production of psi, psi', and upsilon states, exclusive gamma-gamma, chi(c/b) and Di-Jet production at the Tevatron, to exclusive Higgs boson production p+p -> p+H+p and p+WW+p production at the LHC. A proposal to measure the latter processes will be described; in some scenarios it is uniquely (pre-ILC) able to measure such Higgs properties as widths and quantum numbers.