QCD Confinement and the Hall D Project at Jefferson Lab
نویسنده
چکیده
An understanding of the confinement mechanism in QCD requires a detailed mapping of the spectrum of hybrid mesons. Understanding confinement means understanding the role of gluons and it is in hybrid mesons that the gluonic degrees of freedom are manifest. High statistics searches for such states with π and p beams have resulted in some tantalizing signals. There is good reason to expect beams of photons to yield hybrid mesons with JPC quantum numbers not possible within the conventional picture of mesons as qq̄ bound states. Meager data currently exist on the photoproduction of light quark mesons. At Jefferson Lab in Newport News, VA plans are underway to upgrade the energy of the electron accelerator to 12 GeV. Along with this energy upgrade, a hermetic detector housed in new experimental hall (Hall D) will be used to collect data on photoproduced mesons with unprecedented statistics [1, 2]. With 12 GeV electrons, a 9-GeV linearly polarized photon beam will be produced using the coherent bremsstrahlung technique.
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