Speaker
Description
I will discuss some recent lattice QCD calculations of $DK$ and $D\bar{K}$ scattering, relevant for the enigmatic $D^\ast_{s0}(2317)$, with light-quark masses corresponding to $m_\pi = 239$ MeV and $m_\pi = 391$ MeV. The S-waves contain interesting features including a near-threshold $J^P = 0^+$ bound state in isospin-0 $DK$, corresponding to the $D^\ast_{s0}(2317)$, with an effect that is clearly visible above threshold, and suggestions of a $0^+$ virtual bound state in isospin-0 $D\bar{K}$. The S-wave isospin-1 $D\bar{K}$ amplitude is found to be weakly repulsive. There is a deeply bound $D^\ast$ vector resonance, but negligibly small P-wave $DK$ interactions are observed in the energy region considered; the P and D-wave $D\bar{K}$ amplitudes are also small.
Based on material in arXiv:2008.06432
G. K. C. Cheung, C. E. Thomas, D. J. Wilson, G. Moir, M. Peardon, S. M. Ryan,
for the Hadron Spectrum Collaboration