Charmonium and XYZ Physics Too much to cover in 10 minutes Will show a few topics Keith Gollwitzer –Fermilab Antiproton Source – Nov 17, 2007
Charmonium and XYZ Physics Spectroscopy based upon method exploited by Fermilab E760/E835 and to be used at GSI FAIR by PANDA Annihilation of pbar p to form each state All quantum numbers can be formed Keith Gollwitzer –Fermilab Antiproton Source – Nov 17, 2007
Yuan at QWG
Charmonium and XYZ Physics Spectroscopy based upon method exploited by Fermilab E760/E835 and to be used at GSI FAIR by PANDA Annihilation of pbar p to form each state All quantum numbers can be formed Scan beam energy to map out resonance Keith Gollwitzer –Fermilab Antiproton Source – Nov 17, 2007
Beam Profiles Breit-Wigner line shape Beam Scan of ψ(2S) Convolution results in the observed cross section Most precise measurement of the ψ(2S) width despite much smaller statistics than e + e - E835
The precision of the mass and width of the c needs to be improved E760 & E835 only reported pbarp 2photons Need to observe in more channels
1 P 1 or h c J PC = The h c mass is important to understanding hyperfine splitting. The h c width has not been measured
Interference can be your friend The continuum “amplifies” the resonance E835 example in 4 photons pbarp c0 π 0 π 0, , / Should expand interference analyses to more channels; in particular pbarp at 90 o
XYZ States StateJ PC MassDecay Modes X(3872) ±0.5J/ψ π + π -, J/ψ π + π - π 0, J/ψ γ X(3872)? ?? ±0.7D 0 D 0 π 0, D 0 D * Z(3930) ±6D 0 D 0, D + D - Y(3940)? ±17J/ψ ω X(3940)? ?+ 3942±9D D*D D* Y(4008) ±65J/ψ π + π - X(4160)? ?+ 4156±27D * Y(4260) ,4284,4247J/ψ π + π -, J/ψ π 0 π 0, J/ψ K + K - Y(4350) , 4361ψ(2S) π + π - Z + (4430)? 4433±5ψ(2S) π + Y(4620) ±13ψ(2S) π + π -
X(3872) seen in several J/ channels
X(3872) seen also in charm meson channels with a slightly different mass
XYZ States Can precisely measure –Mass & width (ranging few MeV to ~100MeV) Can determine J PC What are these states???? –Charmonium, hybrids, molecules, tetraquarks
Charmonium and XYZ Physics The Accumulator can be ready four months after the conclusion of Tevatron Run II Keith Gollwitzer –Fermilab Antiproton Source – Nov 17, 2007