TY  - JOUR
AU  - Belle II Collaboration (Abudinen, F. et al
AU  - Marinas, C.
PY  - 2021
DA  - 2021//
TI  - Search for B+ -> K+nu(nu)over-bar Decays Using an Inclusive Tagging Method at Belle H
T2  - Phys. Rev. Lett.
JO  - Physical Review Letters
SP  - 181802 - 10pp
VL  - 127
IS  - 18
PB  - Amer Physical Soc
AB  - A search for the flavor-changing neutral-current decay B+ -> K+nu(nu) over bar is performed at the Belle II experiment at the SuperKEKB asymmetric energy electron-positron collider. The data sample corresponds to an integrated luminosity of 63 fb(-1) collected at the Upsilon(4S) resonance and a sample of 9 fb(-1) collected at an energy 60 MeV below the resonance. Because the measurable decay signature involves only a single charged kaon, a novel measurement approach is used that exploits not only the properties of the B+ -> K+nu(nu) over bar decay, but also the inclusive properties of the other B meson in the Upsilon(4S) -> B (B) over bar event, to suppress the background from other B meson decays and light-quark pair production. This inclusive tagging approach offers a higher signal efficiency compared to previous searches. No significant signal is observed. An upper limit on the branching fraction of B+ -> K+nu(nu) over bar of 4.1 x 10(-5) is set at the 90% confidence level.
SN  - 0031-9007
UR  - https://arxiv.org/abs/2104.12624
UR  - https://doi.org/10.1103/PhysRevLett.127.181802
DO  - 10.1103/PhysRevLett.127.181802
LA  - English
N1  - WOS:000712526000010
ID  - BelleIICollaborationAbudinen+Marinas2021
ER  -