{"id":39010,"date":"2026-08-21T15:27:57","date_gmt":"2026-08-21T15:27:57","guid":{"rendered":"https:\/\/lamarr-institute.org\/publication\/searches-for-b0-to-kpi-tautau-and-b0_s-to-kk-tautau-decays\/"},"modified":"2026-09-17T11:18:07","modified_gmt":"2026-09-17T11:18:07","slug":"searches-for-b0-to-kpi-tautau-and-b0_s-to-kk-tautau-decays","status":"publish","type":"publication","link":"https:\/\/lamarr-institute.org\/de\/publication\/searches-for-b0-to-kpi-tautau-and-b0_s-to-kk-tautau-decays\/","title":{"rendered":"Searches for $B^0 \\to K^+\\pi^-\\tau^+\\tau^-$ and $B^0_s \\to K^+K^-\\tau^+\\tau^-$ Decays"},"content":{"rendered":"<p>The first searches for $B^0 \\to K^+\\pi^-\\tau^+\\tau^-$ and $B^0_s \\to K^+K^-\\tau^+\\tau^-$ decays at the LHCb experiment are conducted with $pp$ collision data corresponding to an integrated luminosity of 5.4 fb$^{-1}$. The tau leptons are reconstructed using the $\\tau^+ \\to \\mu^+\\bar{\\nu}_\\tau\\nu_\\mu$ decay and the results are presented in bins of $K^+\\pi^-$ or $K^+K^-$ mass. No signal is observed and upper limits are set on the branching fractions. The searches result in the first upper limits for $B^0 \\to K^+\\pi^-\\tau^+\\tau^-$ decays outside the $K(892)^0$ region in $K^+\\pi^-$ mass and the first limits for $B^0_s \\to K^+K^-\\tau^+\\tau^-$ decays. The searches are recast into limits on the decays $B^0 \\to K(892)^0\\tau^+\\tau^-$ and $B^0_s \\to \\phi(1020)\\tau^+\\tau^-$, yielding $2.8 \\times 10^{-4}$ ($2.5 \\times 10^{-4}$) and $4.7 \\times 10^{-4}$ ($4.1 \\times 10^{-4}$) at the 95\\% (90\\%) confidence level, respectively. For the decay $B^0 \\to K(892)^0\\tau^+\\tau^-$, this result improves on the current best upper limit by an order of magnitude.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>The first searches for $B^0 \\to K^+\\pi^-\\tau^+\\tau^-$ and $B^0_s \\to K^+K^-\\tau^+\\tau^-$ decays at the LHCb experiment are conducted with $pp$ collision data corresponding to an integrated luminosity of 5.4 fb$^{-1}$. The tau leptons are reconstructed using the $\\tau^+ \\to \\mu^+\\bar{\\nu}_\\tau\\nu_\\mu$ decay and the results are presented in bins of $K^+\\pi^-$ or $K^+K^-$ mass. No signal is observed and upper limits are set on the branching fractions. The searches result in [&hellip;]<\/p>\n","protected":false},"author":14,"featured_media":0,"template":"","meta":{"_acf_changed":false,"footnotes":""},"publication-type":[30],"class_list":["post-39010","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\/39010","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\/39010\/revisions"}],"wp:attachment":[{"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/media?parent=39010"}],"wp:term":[{"taxonomy":"publication-type","embeddable":true,"href":"https:\/\/lamarr-institute.org\/de\/wp-json\/wp\/v2\/publication-type?post=39010"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}