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排序方式: 共有268条查询结果,搜索用时 15 毫秒
91.
Zhang J Nakao M Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bahinipati S Bakich AM Ban Y Banas E Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Gordon A Guo R Handa F Hara T Hastings NC Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igarashi Y Iijima T 《Physical review letters》2003,91(22):221801
We report the first observation of the charmless vector-vector decay process B-/+-->rho(-/+)rho(0). The measurement uses a 78 fb(-1) data sample collected with the Belle detector at the KEKB asymmetric e(+)e(-) collider operating at the Upsilon(4S) resonance. We obtain a branching fraction of B(B-/+-->rho(-/+)rho(0))=[31.7+/-7.1(stat)+3.8-6.7(syst)]x10(-6). An analysis of the rho helicity-angle distributions gives a longitudinal polarization fraction of Gamma(L)/Gamma=0.95+/-0.11(stat)+/-0.02(syst). We also measure the direct-CP-violating asymmetry A(CP)(B-/+-->rho(-/+)rho(0))=0.00+/-0.22(stat)+/-0.03(syst). 相似文献
92.
A dilatometer with an imprecision of less than 0.4% is described for the determination of partial molar volumes of gases dissolved in liquids. Measurements at 298.15 K are reported for 40 liquid-gas systems having n-alkanes and 1-alkanols as the liquid component. The results are interpreted in terms of a number of empirical and semiempirical correlations. 相似文献
93.
T Fujii H Kanai J Mirayama K Handa S Kusama K Yano M Miyazawa M Takizawa 《Radioisotopes》1979,28(12):751-756
The dual radioisotope techniques with 201TlCl and 99mTcO4- were performed in 30 cases inclusive of various heart and lung diseases, using a scintillation camera coupling to a small digital computer. The scintigraphic procedures were started about 5 minutes after intravenous injection of 201TlCl. The myocardial images such as anterior, 60 degrees left anterior oblique, and left lateral view, were obtained. Next, 30 degrees left anterior oblique view was taken and radionuclide angiogram with 99mTcO4- was done in the same position too. This joint use of the myocardial imaging and radionuclide angiography could increase diagnostic reliability. Superimposing the image as iso-count map extracted out of radionuclide angiogram to the brightness image of 201TlCl, the anatomic orientation of the image of 201TlCl was improved. Subtracting the blood pool image with 99mTcO4- or radionuclide angiogram, which showed visualization of the right ventricle, lungs and left ventricle, from the image of 201TlCl, the subtraction image was obtained. The right ventricle was visualized more clearly on this subtraction image than the original image of 201TlCl. Good visualization of the right ventricle was shown in 25 cases on the subtraction image, and in 17 cases on the original image of 201TlCl. 相似文献
94.
95.
Enari Y Abe K Abe K Abe T Adachi I Aihara H Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Bedny I Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Cheon BG Choi SK Choi Y Choi YK Chuvikov A Danilov M Dong LY Eidelman S Eiges V Epifanov D Fukunaga C Gabyshev N Garmash A Gershon T Gokhroo G Golob B Handa F Hara T Hayasaka K Hayashii H Hazumi M Hokuue T Hoshi Y Hou WS Huang HC Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki M Iwasaki Y Kang JH Kang JS Kataoka SU Katayama N Kawai H 《Physical review letters》2004,93(8):081803
We have searched for the lepton flavor violating decay tau(-)-->micro(-)eta using a data sample of 84.3 fb(-1) accumulated with the Belle detector at KEK. The eta meson was detected through the decay modes: eta-->gammagamma and pi(+)pi(-)pi(0). No signal candidates are found, and we obtain an upper limit for the branching fraction B(tau(-)-->micro(-)eta)<3.4 x 10(-7) at the 90% confidence level. 相似文献
96.
Abe K Abe K Abe R Abe T Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bay A Bedny I Behera PK Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Danilov M Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Fang F Fukunaga C Gabyshev N Garmash A Gershon T Gordon A Guo R Handa F Hara T Harada Y Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hojo T Hokune T Hoshi Y Hoshina K Hou SR 《Physical review letters》2002,89(15):151802
The B meson decay modes B-->Dpp; and B-->D(*)pp; have been studied using 29.4 fb(-1) of data collected with the Belle detector at KEKB. The B;(0)-->D(0)pp; and B;(0)-->D(*0)pp; decays have been observed for the first time with branching fractions B(B;(0)-->D(0)pp;)=(1.18+/-0.15+/-0.16)x10(-4) and B(B;(0)-->D(*0)pp;)=(1.20(+0.33)(-0.29)+/-0.21)x10(-4). No signal has been found for the B+-->D(+)pp; and B+-->D(*+)pp; decay modes, and the corresponding upper limits at 90% C.L. are presented. 相似文献
97.
Abe K Abe K Abe R Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aushev T Bakich AM Ban Y Banas E Behari S Behera PK Bondar A Bozek A Brodzicka J Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Dong LY Dragic J Drutskoy A Eidelman S Eiges V Enari Y Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Gordon A Guler H Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T 《Physical review letters》2002,88(17):171801
The lifetimes of the B(0) and B- mesons are extracted from 29.1 fb(-1) of data collected with the Belle detector at the KEK B factory. A fit to the decay length differences of neutral and charged B meson pairs, measured in events where one of the B mesons is fully reconstructed in several hadronic modes, yields tau(B(0)) = 1.554+/-0.030(stat)+/-0.019(syst) ps, tau(B-) = 1.695+/-0.026(stat)+/-0.015(syst) ps, and tau(B-)/tau(B(0)) = 1.091+/-0.023(stat)+/-0.014(syst). 相似文献
98.
Abe K Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Behari S Behera PK Bondar A Bozek A Bracko M Browder TE Casey BC Chang P Chao Y Cheon BG Chistov R Choi SK Choi Y Dong LY Dragic J Drutskoy A Eidelman S Eiges V Everton CW Fang F Fujii H Fukunaga C Fukushima M Gabyshev N Garmash A Gershon T Golob B Gordon A Gotow K Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hojo T 《Physical review letters》2002,89(1):011803
We report the first observation of chi(c2) production in B meson decays. We find an inclusive B-->chi(c2)X branching fraction of (1.80(+0.23)(-0.28)+/-0.26) x 10(-3). The data set, collected with the Belle detector at the KEKB e(+)e(-) collider, consists of 31.9 x 10(6) BB events. We also present branching fractions and momentum spectra for both chi(c1) and chi(c2) production. 相似文献
99.
Abe K Abe K Adachi I Ahn BS Aihara H Akatsu M Alimonti G Asano Y Aso T Aulchenko V Aushev T Bakich AM Bartel W Behari S Behera PK Beiline D Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Choi SK Choi Y Eidelman S Enari Y Enomoto R Fang F Fujii H Fukushima M Garmash A Gordon A Gotow K Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hirano H Hojo T Hoshi Y Hou WS Hsu SC Huang HC Igarashi Y Iijima T 《Physical review letters》2001,87(10):101801
100.
Abe K Abe K Adachi I Ahn BS Aihara H Akatsu M Alimonti G Asano Y Aso T Aulchenko V Aushev T Bakich AM Bartel W Behari S Behera PK Beiline D Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Cheon BG Choi SK Choi Y Eidelman S Enari Y Enomoto R Fang F Fujii H Fukunaga C Fukushima M Garmash A Gordon A Gotow K Guo R Haba J Hamasaki H Hanagaki K Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hirano H Hojo T Hoshi Y Hou WS Hsu SC Huang HC Igarashi Y Iijima T 《Physical review letters》2001,87(11):111801
We report observations of the Cabibbo suppressed decays B-->D((*))K- using a 10.4 fb(-1) data sample accumulated at the Upsilon(4S) resonance with the Belle detector at the KEKB e(+)e(-) storage ring. We find that the ratios of Cabibbo suppressed to Cabibbo favored branching fractions are B(B--->D0K-)/B(B--->D0pi(-)) = 0.079+/-0.009+/-0.006, B(B(0)-->D+K-)/B(B(0)-->D+pi(-)) = 0.068+/-0.015+/-0.007, B(B--->D(*0)K-)/B(B--->D(*0)pi(-)) = 0.078+/-0.019+/-0.009, and B(B(0)-->D(*+)K-)/B(B(0)-->D(*+)pi(-)) = 0.074+/-0.015+/-0.006. These are the first observations of the B-->D+K-, D(*0)K-, and D(*+)K- decay processes. 相似文献