A search for $D^0$ meson decays to the $\\pi^+\\pi^-e^+e^-$ and $K^+K^-e^+e^-$ final states is reported using a sample of proton-proton collisions collected by the LHCb experiment at a center-of-mass energy of 13\\,{Te\\kern -0.1em V}, corresponding to an integrated luminosity of 6\\,fb$^{-1}$. The decay $D^0 \\rightarrow \\pi^+\\pi^-e^+e^-$ is observed for the first time when requiring that the two electrons are consistent with coming from the decay of a $\\phi$ or $\\rho^0\/\\omega$ meson. The corresponding branching fractions are measured relative to the $D^0 \\rightarrow K^-\\pi^-[e^+e^-]_{\\rho^0\/\\omega}$ decay, where the two electrons are consistent with coming from the decay of a $\\rho^0$ or $\\omega$ meson. <\/p>\n
No evidence is found for the $D^0 \\rightarrow K^+K^-e^+e^-$ decay and world-best limits are set on its branching fraction. The results are compared to, and found to be consistent with, the branching fractions of the $D^0 \\rightarrow \\pi^+\\pi^-\\mu^+\\mu^-$ and $D^0 \\rightarrow K^+K^-\\mu^+\\mu^-$ decays recently measured by LHCb and confirm lepton universality at the current precision.<\/p>\n","protected":false},"excerpt":{"rendered":"
A search for $D^0$ meson decays to the $\\pi^+\\pi^-e^+e^-$ and $K^+K^-e^+e^-$ final states is reported using a sample of proton-proton collisions collected by the LHCb experiment at a center-of-mass energy of 13\\,{Te\\kern -0.1em V}, corresponding to an integrated luminosity of 6\\,fb$^{-1}$. The decay $D^0 \\rightarrow \\pi^+\\pi^-e^+e^-$ is observed for the first time when requiring that the two electrons are consistent with coming from the decay of a $\\phi$ or $\\rho^0\/\\omega$ […]<\/p>\n","protected":false},"author":14,"featured_media":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"publication-type":[30],"class_list":["post-32285","publication","type-publication","status-publish","hentry","publication-type-article"],"acf":[],"publishpress_future_workflow_manual_trigger":{"enabledWorkflows":[]},"_links":{"self":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication\/32285","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication"}],"about":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/types\/publication"}],"author":[{"embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/users\/14"}],"version-history":[{"count":0,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication\/32285\/revisions"}],"wp:attachment":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/media?parent=32285"}],"wp:term":[{"taxonomy":"publication-type","embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication-type?post=32285"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}