Measurement of the branching fraction of the decay ▫$B^- \to D^0 \rho(770)^-$▫ at Belle IIAdachi, Ichiro (Avtor) Bračko, Marko (Avtor) Feichtinger, Paul (Avtor) Ganiev, Eldar (Avtor) Marino, Gaetano de (Avtor) Korpar, Samo (Avtor) Križan, Peter (Avtor) Mrvar, Manca (Avtor) Novosel, Anja (Avtor) Pestotnik, Rok (Avtor) Podobnik, Tomaž (Avtor) Prudiiev, Ihor (Avtor) Starič, Marko (Avtor) Šantelj, Luka (Avtor) Zhukova, Valentina (Avtor) Belle experimentbeyond standard modelmagnetic spectrometerWe measure the branching fraction of the decay �−→�0⁢�⁢(770)− using data collected with the Belle II detector. The data contain 387 million �⁢ ¯ � pairs produced in �+⁢�− collisions at the ϒ⁡(4⁢�) resonance. We reconstruct 8360±180 decays from an analysis of the distributions of the �− energy and the �⁢(770)− helicity angle. We determine the branching fraction to be (0.939±0.021⁢(stat)±0.050⁢(syst))%, in agreement with previous results. Our measurement improves the relative precision of the world average by more than a factor of two.American Physical Society20242026-04-20 08:26:42Neznano29041ZDAsl