Molecular states with charm: insights from vacuum and finite-temperature analyses

This contribution to the SQM2024 conference covers the molecular hypothesis for the internal structure of some open and hidden charm states. The use of effective theories that incorporate heavy-quark spin symmetry, combined with unitarization techniques, has provided strong evidences supporting this interpretation. In the heavy-light sector, we discuss the double pole structure of the $D_0^{\ast }(2300)$ and the generation of the $D_{s0}^{\ast }(2317)$. In the hidden charm sector, we focus on the exotic $X(3872)$ and its heavy-quark partner, the $X(4014)$. Furthermore, we emphasize the benefits of femtoscopic measurements in $p+p$ collisions to establish the nature of these states, as well as the potential role of temperature to discern their internal structure.