Charge-conjugation asymmetry and molecular content: the D_s0^∗(2317)^± in matter

We analyze the modifications that a dense nuclear medium induces in the D_s0^∗(2317)^± and D_s1(2460)^±. In the vacuum, we consider them as isoscalar D^(*)K and D^(*)K S-wave bound states, which are dynamically generated from effective interactions that lead to different Weinberg compositeness scenarios. Matter effects are incorporated through the two-meson loop functions, taking into account the self energies that the D^(*), D^(*), K, and K develop when embedded in a nuclear medium. Although particle-antiparticle [D^(∗)_s0,s1(2317,2460)^+ versus D^(∗)_s0,s1(2317,2460)^-] lineshapes are the same in vacuum, we find extremely different density patterns in matter. This charge-conjugation asymmetry mainly stems from the very different kaon and antikaon interaction with the nucleons of the dense medium. We show that the in-medium lineshapes found for these resonances strongly depend on their D^(*)K/D^(*)K molecular content, and discuss how this novel feature can be used to better determine/constrain the inner structure of these exotic states.