2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/176614We present a theoretical framework that accounts for the new $D_J$ and $D_{sJ}$ mesons measured in the open-charm sector. These resonances are properly described if considered as a mixture of conventional $P-$wave quark-antiquark states and four-quark components. The narrowest states are basically $P-$wave quark-antiquark mesons, while the dominantly four-quark states are shifted above the corresponding two-meson threshold. We study the electromagnetic decay widths as basic tools to scrutiny their nature.4 pages, to appear in the proceedings of 9th International Workshop on Meson Production, Properties and Interaction (Meson2006), Kracow (Poland), 9 - 13 June 2006High Energy Physics - Phenomenologytext