検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年
検索結果: 3 件中 1件目~3件目を表示
  • 1

発表形式

Initialising ...

選択項目を絞り込む

掲載資料名

Initialising ...

発表会議名

Initialising ...

筆頭著者名

Initialising ...

キーワード

Initialising ...

使用言語

Initialising ...

発行年

Initialising ...

開催年

Initialising ...

選択した検索結果をダウンロード

論文

Search for transitions from $$Upsilon(4S)$$ and $$Upsilon(5S)$$ to $$eta_b(1S)$$ and $$eta_b(2S)$$ with emission of an $$omega$$ meson

Oskin, P.*; 谷田 聖; Belle Collaboration*; 他198名*

Physical Review D, 102(9), p.092011_1 - 092011_8, 2020/11

 被引用回数:0 パーセンタイル:0.01(Astronomy & Astrophysics)

Using data collected in the Belle experiment at the KEKB asymmetric-energy $$e^+e^-$$ collider we search for transitions $$Upsilon(4S) rightarrow eta_b(1S)omega$$, $$Upsilon(5S) rightarrow eta_b(1S)omega$$ and $$Upsilon(5S) rightarrow eta_b(2S)omega$$. No significant signals are observed and we set 90% confidence level upper limits on the corresponding visible cross sections: $$0.2 ~textrm{pb}, 0.4 ~textrm{pb}$$ and $$1.9 ~textrm{pb}$$, respectively.

論文

Observation of $$tau^- rightarrow pi^- nu_{tau} e^+ e^- $$ and search for $$tau^- rightarrow pi^- nu_{tau} mu^+ mu^-$$

Jin, Y.*; 谷田 聖; Belle Collaboration*; 他198名*

Physical Review D, 100(7), p.071101_1 - 071101_9, 2019/10

 被引用回数:3 パーセンタイル:20.44(Astronomy & Astrophysics)

We present the first measurements of branching fractions of rare tau-lepton decays, $$tau^- rightarrow pi^- nu_{tau} ell^+ ell^-$$ ($$ell = e$$ or $$mu$$), using a data sample corresponding to 562 fb$$^{-1}$$ collected at a center-of-mass energy of 10.58 GeV with the Belle detector at the KEKB asymmetric-energy $$e^+ e^-$$ collider. The $$tau^- rightarrow pi^- nu_tau e^+ e^-$$ decay is observed for the first time with 7.0$$sigma$$ significance. The partial branching fraction determined by the structure-dependent mechanisms mediated by either a vector or an axial-vector current for the mass region $$M_{pi e e} > 1.05$$ GeV/$$c^2$$ is measured to be $$mathcal{B}(tau^-rightarrow pi^- nu_tau e^+ e^-)[M_{pi^- e^+ e^-} > 1.05~{rm GeV}/c^2] = (5.90 pm 0.53 pm 0.85 pm 0.11) times 10^{-6}$$, where the first uncertainty is statistical, the second is systematic, and the third is due to the model dependence. In the full phase space, due to the different detection efficiencies for the structure-dependent mechanisms mediated by axial-vector and vector currents, the branching fraction varies from $$mathcal{B}_{A}(tau^-rightarrow pi^- nu_tau e^+ e^-) = (1.46 pm 0.13 pm 0.21) times 10^{-5}$$ to $$mathcal{B}_{V}(tau^-rightarrow pi^- nu_tau e^+ e^-) = (3.01 pm 0.27 pm 0.43) times 10^{-5}$$, respectively. An upper limit is set on the branching fraction of the $$tau^- rightarrow pi^- nu_tau mu^+ mu^-$$ decay, $$mathcal{B}(tau^-rightarrow pi^- nu_tau mu^+ mu^-) < 1.14 times 10^{-5}$$, at the 90% confidence level.

論文

Search for $$CP$$ violation and measurement of the branching fraction in the decay $$D^{0} to K^0_S K^0_S$$

Dash, N.*; 谷田 聖; Belle Collaboration*; 他198名*

Physical Review Letters, 119(17), p.171801_1 - 171801_7, 2017/10

AA2017-0514.pdf:0.35MB

 被引用回数:32 パーセンタイル:86.53(Physics, Multidisciplinary)

We report a study of the decay $$D^{0} to K^0_S K^0_S$$ using 921 fb$$^{-1}$$ of data collected at or near the $$Upsilon(4S)$$ and $$Upsilon(5S)$$ resonances with the Belle detector at the KEKB asymmetric energy $$e^+e^-$$ collider. The measured time-integrated $$CP$$ asymmetry is $$A_{CP}(D^{0} to K^0_S K^0_S)=(-0.02 pm 1.53 pm 0.02 pm 0.17)%$$, and the branching fraction is $$B(D^{0} to K^0_S K^0_S)=(1.321 pm 0.023 pm 0.036 pm 0.044) times 10^{-4}$$, where the first uncertainty is statistical, the second is systematic, and the third is due to the normalization mode ($$D^{0} to K^0_S pi^0$$). These results are significantly more precise than previous measurements available for this mode. The $$A_{CP}$$ measurement is consistent with the standard model expectation.

3 件中 1件目~3件目を表示
  • 1