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排序方式: 共有192条查询结果,搜索用时 31 毫秒
101.
102.
Ikado K Abe K Abe K Adachi I Aihara H Akai K Akemoto M Anipko D Arinstein K Aulchenko V Aushev T Aziz T Bakich AM Balagura V Barbero M Bay A Bedny I Belous K Bitenc U Bizjak I Bondar A Bozek A Bracko M Browder TE Chang P Chen A Chen WT Choi Y Cole S Dalseno J Danilov M Dash M Eidelman S Epifanov D Flanagan J Fratina S Furukawa K Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Ha H Haba J Hara K Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS Iida N 《Physical review letters》2006,97(25):251802
We present the first evidence of the decay B- --> tau- nu(tau), 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 3.5 standard deviations including systematics and measure the branching fraction to be B(B- --> tau- nu(tau)) = (1.79(-0.49) +0.56(stat)(-0.51) +0.46(syst)) x 10(-4). This implies that fB = 0.229(-0.031) +0.036(stat)(-0.037) +0.034(syst) GeV and is the first direct measurement of this quantity. 相似文献
103.
Schümann J Wang CH Abe K Adachi I Aihara H Anipko D Arinstein K Asano Y Aushev T Bakich AM Balagura V Barberio E Barbero M Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Browder TE Chang MC Chang P Chao Y Chen A Chen WT Cheon BG Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Ha HC Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T 《Physical review letters》2006,97(6):061802
We report evidence for the exclusive two-body charmless hadronic B meson decay B-->eta'pi, and improved measurements of B-->eta'K. The results are obtained from a data sample of 386x10(6) BB pairs collected at the Upsilon(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e+e- collider. We measure B(B+-->eta'pi+)=[1.76(-0.62)(+0.67)(stat)(-0.14)(+0.15)(syst)]x10(-6) and B(B0-->eta'pi0)=[2.79(-0.96)(+1.02)(stat)(-0.34)(+0.25)(syst)]x10(-6). We also find the ratio of B(B+-->eta'K+)/B(B0-->eta'K0)=1.17+/-0.08(stat)+/-0.03(syst) and measure the direct CP asymmetries for the charged modes. 相似文献
104.
Hisaki Otani Sakiko Fujita Yu Watanabe Michiya Fujiki Kotohiro Nomura 《Macromolecular Symposia》2010,293(1):53-57
Summary: Precise syntheses of soluble star polymers containing a sugar residue could be attained by adopting sequential ring-opening metathesis polymerizations of norbornene, 1,4,4a,5,8,8a-hexahydro-1,4,5,8-exo-endo-dimethanonaphtalene, and then 1,2:3,4-di-O-isopropylidene-α-D-galacto-pyranos-6-O-yl 5-norbornene-2-carboxylate using Mo(CHCMe2Ph)(N-2,6-iPr2C6H3)(OtBu)2. The resultant polymers possessed uniform molecular weight distributions, and the Mn values could be varied by the monomer/Mo molar ratios; their spherical images were observed in the TEM micrographs. 相似文献
105.
Hara K Hazumi M Abe K Abe K Abe T Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Bay A Bedny I Behera PK Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Dong LY Dragic J Eidelman S Eiges V Enari Y Everton CW Fang F Fukunaga C Gabyshev N Garmash A Gershon T Golob B Guo R Haba J Hanagaki K Handa F Hara T Hastings NC Hayashii H Heenan EM Higuchi I Higuchi T Hinz L 《Physical review letters》2002,89(25):251803
We present a measurement of the B0-Bmacr;(0) mixing parameter Deltam(d) using neutral B meson pairs in a 29.1 fb(-1) data sample collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. We exclusively reconstruct one neutral B meson in the semileptonic B0-->D(*-)l(+)nu decay mode and identify the flavor of the accompanying B meson from its decay products. From the distribution of the time intervals between the two flavor-tagged B meson decay points, we obtain Deltam(d)=(0.494+/-0.012+/-0.015) ps(-1), where the first error is statistical and the second error is systematic. 相似文献
106.
Abe K Abe K Abe R Adachi I Ahn BS Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Banas E Behari S Behera PK Bondar A Bozek A Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Dong LY Dragic J Drutskoy A Eidelman S Enari Y Fang F Fujii H Fukushima M Gabyshev N Garmash A Gershon T Gordon A Gotow K Guo R Haba J Hamasaki H Handa F Hara K Hara T Hastings NC Hayashii H Hazumi M Heenan EM Higuchi I Higuchi T Hirano H Hojo T Hokuue T Hoshina K Hou SR Hou WS 《Physical review letters》2002,88(5):052002
We report the first observation of color-suppressed B( 0)-->D(0)pi(0), D(*0)pi(0), D0eta, and D0omega decays, and evidence for B( 0)-->D(*0)eta and D(*0)omega. The branching fractions are B(B( 0)-->D0pi(0)) = (3.1 +/- 0.4 +/- 0.5)x10(-4), B(B( 0) -->D(*0)pi(0)) = (2.7(+0.8+0.5)(-0.7-0.6))x10(-4), B(B( 0) --> D0eta) = (1.4(+0.5)(-0.4) +/- 0.3)x10(-4), B(B( 0) --> D0omega) = (1.8 +/- 0.5(+0.4)(-0.3))x10(-4), and we set 90% confidence level upper limits of B(B( 0) --> D(*0)eta)<4.6 x 10(-4) and B(B( 0)-->D(*0)omega)<7.9 x 10(-4). The analysis is based on a data sample of 21.3 fb(-1) collected at the Upsilon(4S) resonance by the Belle detector at the KEKB e(+)e(-) collider. 相似文献
107.
Lu RS Abe K Abe K Abe N Abe R Abe T Adachi I Aihara H Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Banas E Bedny I Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chang MC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Dong LY Drutskoy A Eidelman S Eiges V Everton CW Fukunaga C Gabyshev N Gershon T Golob B Gordon A Guo R Haba J Hara T Harada Y Hayashii H Hazumi M Heenan EM Higuchi T Hinz L Hokuue T Hoshi Y Hou WS Hsu SC Huang HC Igaki T 《Physical review letters》2002,89(19):191801
We report the first observation of the charmless two-body mode B+/--->omegaK+/- decay, and a new measurement of the branching fraction for the B+/--->omegapi(+/-) decay. The measured branching fractions are B(B+/--->omegaK+/-)=(9.2(+2.6)(-2.3)+/-1.0)x10(-6) and B(B+/--->omegapi(+/-))=(4.2(+2.0)(-1.8)+/-0.5)x10(-6). We also measure the partial rate asymmetry of B+/--->omegaK+/- decays and obtain A(CP)=-0.21+/-0.28+/-0.03. The results are based on a data sample of 29.4 fb(-1) collected on the Upsilon(4S) resonance by the Belle detector at the KEKB e(+)e(-) collider. 相似文献
108.
Krokovny P Abe K Abe T Adachi I Aihara H Akatsu M Asano Y Aso T Aulchenko V Aushev T Bakich AM Ban Y Bay A Bedny I Bondar A Bozek A Bracko M Brodzicka J Browder TE Casey BC Chang P Chao Y Chen KF Cheon BG Chistov R Choi SK Choi Y Choi YK Danilov M Drutskoy A Eidelman S Eiges V Enari Y Fukunaga C Gabyshev N Garmash A Gershon T Haba J Hara T Hasuko K Hayashii H Hazumi M Higuchi I Higuchi T Hojo T Hoshi Y Hou WS Huang HC Igarashi Y Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki Y Kaneko J 《Physical review letters》2003,90(14):141802
We report on a search for B(0)-->D(*0)K(*0) decays based on 85 x 10(6) BB events collected with the Belle detector at KEKB. The B(0)-->D0K(0) and B(0)-->D0K(*0) decays have been observed for the first time with the branching fractions B(B(0)-->D0K(0))=(5.0(+1.3)(-1.2)+/-0.6)x10(-5) and B(B(0)-->D0K(*0))=(4.8(+1.1)(-1.0)+/-0.5)x10(-5). No significant signal has been found for the B(0)-->D(*0)K*0) and B(0)-->D(*0)K(*0) decay modes, and upper limits at 90% C.L. are presented. 相似文献
109.
Mikami Y Abe K Abe T Aihara H Akemoto M Asano Y Aso T Aushev T Bahinipati S Bakich AM Ban Y Bay A Bizjak I Bondar A Bozek A Bracko M Browder TE Chao Y Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Danilov M Dong LY Dragic J Eidelman S Eiges V Fukunaga C Furukawa K Gabyshev N Garmash A Gershon T Gokhroo G Golob B Handa F Hara T Hayashii H Hazumi M Higuchi I Hinz L Hokuue T Hoshi Y Hou WS Huang HC Iijima T Ikeda H Inami K Ishikawa A Iwasaki H Iwasaki M Iwasaki Y Kang JH Kang JS Kapusta P 《Physical review letters》2004,92(1):012002
We report measurements of the properties of the D(+)(sJ)(2317) and D(+)(sJ)(2457) resonances produced in continuum e(+)e(-) annihilation near sqrt[s]=10.6 GeV. The analysis is based on an 86.9 fb(-1) data sample collected with the Belle detector at KEKB. We determine the masses to be M(D(+)(sJ)(2317))=2317.2+/-0.5(stat)+/-0.9(syst) MeV/c(2) and M(D(+)(sJ)(2457))=2456.5+/-1.3(stat)+/-1.3(syst) MeV/c(2). We observe the radiative decay mode D(+)(sJ)(2457)-->D(+)(s)gamma and the dipion decay mode D(+)(sJ)(2457)-->D(+)(s)pi(+)pi(-) and determine their branching fractions. No corresponding decays are observed for the D(sJ)(2317) state. These results are consistent with the spin-parity assignments of 0(+) for the D(sJ)(2317) and 1(+) for the D(sJ)(2457). 相似文献
110.
Dr. Shunpei Nobusue Hirokazu Miyoshi Dr. Akihiro Shimizu Dr. Ichiro Hisaki Kotaro Fukuda Prof. Masayoshi Nakano Prof. Yoshito Tobe 《Angewandte Chemie (International ed. in English)》2015,54(7):2090-2094
A tetramesityl derivative of hitherto unknown tetracyclopenta[def,jkl,pqr,vwx]tetraphenylene (TCPTP), which is a potential tetraradicaloid hydrocarbon, was synthesized. Theoretical calculations based on spin‐flip time‐dependent density functional theory predict that the closed‐shell D2h form of TCPTP is more stable than the open‐shell D4h form with its slightly tetraradical character. The tetramesityl derivative (Mes)4‐TCPTP exhibits remarkable antiaromaticity as a result of the peripheral 20‐π‐electron circuit, which causes an absorption maximum at a long wavelength and a small HOMO–LUMO gap. In solution, (Mes)4‐TCPTP most likely adopts rapidly equilibrating D2h structures that interconvert via the D4h transition state. X‐ray crystallographic analysis showed (Mes)4‐TCPTP as an approximate D2h structure. 相似文献