Casimir effect and spontaneous chiral symmetry braking in D mesons

Suzuki, Kei   ; Ishikawa, Tsutomu*; Nakayama, Katsumasa*; Suenaga, Daiki*

D mesons are expected to be clear probes of the chiral condensate. For the Casimir effect in the QCD vacuum, non-perturbative properties of the QCD vacuum are modified by the volume size and boundary conditions. In this talk, we focus on the modification of the chiral symmetry breaking by the Casimir effect and the response of D mesons. By using an effective Lagrangian based on chiral partner structures for D mesons, we discuss the dependences on volume, boundary, and temperature, and the applications to lattice QCD simulations.