Speaker
Description
The LHCb collaboration has observed a pentaquark system, $udsc\bar{c}$, with
$J^{\pi} = 1/2^{-}$, whose mass is $4338.2$ MeV with $\Gamma = 7$ MeV [1].
To describe this state, I use a constituent quark model, and the employed
Hamiltonian is based on Semay and Silvestre-Brac [2]. This Hamiltonian
reproduces all of the meson and baryon states which appear in the open channels
of this pentaquark system. For the color wavefunction, we include the excited
effect of color, namely the color octet state. To consider the resonant state of
this pentaquark system, we utilize the real scaling method. The result will be
shown in the workshop.
Reference
[1] S. K. Choi et al. (Belle Collaboration), Phys. Rev. Lett. 91, 262001 (2003).
[2] C. Semay and B. Silvestre-Brac, Z. Phys. C 61, 271 (1994);
B. Silvestre-Brac, Few-Body Syst. 20, 1 (1996).
