Doubly heavy diquark-antiquark symmetry: The little symmetry that might

Paul Hohler, University of Maryland
3:30 PM, March 18, 2008, NC State

In the limit of heavy quark masses going to infinity, a symmetry is known to emerge in QCD relating properties of hadrons with two heavy quarks to analogous states with one heavy antiquark. A key question is whether the charm mass is heavy enough so that this symmetry is manifest in at least an approximate manner. This issue is crucial in attempting to understand the recent reports by the SELEX Collaboration of doubly charmed baryons. It will be argued in this talk on very general grounds that the charm quark mass is substantially too light for the symmetry to emerge automatically via color coulombic interactions. However, the symmetry could emerge approximately depending on the dynamical details of the non-perturbative physics.