# Hot topics from Belle experiment

Source: [Hot topics from Belle experiment](<https://www.sota2.com/research/paper/68fa3a4c1e209131ce8c99b2>)

Collection index: [llms.txt](<https://www.sota2.com/research/llms.txt>)

Data updated: 2025-10-24T23:59:39.870Z

Authors: K. Ikado

Published: 2006-05-16T07:22:44.000Z

## Abstract

We present the first evidence of the decay B- --\> tau- nu\_tau-bar using 414 fb^-1 of data collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. Events are tagged by fully reconstructing one of the B mesons in hadronic modes. We detect the signal with a significance of 4.2 standard deviations including systematics, and measure the branching fraction to be Br(B- --\> tau- nu\_tau-bar) = (1.06 +0.34-0.28(stat) +0.22-0.25(syst))\*10^-4. We also report results based on 1.86 fb^-1 data collected by the Belle detector at the Upsilon(5S) resonance. Several exclusive Bs decays Bs --\> Ds^{(\*)+} pi- (rho-) and Bs --\> J/psi phi(eta) are studied. The Bs meson production is found to proceed predominantly through the creation of Bs^\* Bsbar^\* pairs. Upper limits on Bs --\> K+K-, Bs --\> phi gamma, Bs --\> gamma gamma and Bs --\> Ds^{(\*)+} Ds^{(\*)-} decays are also reported.

## Recorded benchmark results

A research result applies to its stated dataset, split, metric and evaluation configuration. Compare like-for-like settings, preserve the metric's unit and direction, and distinguish paper-reported results from independent reproduction. The best result recorded here is not a claim of exhaustive, current global coverage.

## Original sources and implementation

[Original paper](<https://arxiv.org/abs/hep-ex/0605068>)

[PDF](<https://arxiv.org/pdf/hep-ex/0605068.pdf>)