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71.
Lakshminarasimhan Damodharan Vasantha Pattabhi Manoranjan Behera Sambasivarao Kotha 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(4):o216-o218
The title compounds, C19H19I2NO3 and C19H19Br2NO3, are derivatives of α‐aminoisobutyric acid with halogen substituents at the para and meta positions, respectively. The ethoxycarbonyl and formamide side chains attached to the Cα atom of the molecule adopt extended and folded conformations, respectively. The crystal structures are stabilized by N—H⃛O, C—H⃛O, C—Br⃛O and C—I⃛O interactions. 相似文献
72.
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
73.
Wang MZ Lee YJ Abe K Abe K Abe T Aihara H Akatsu M Asano Y Aso T Aushev T Bakich AM Ban Y Banas E Bay A 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 Y Choi YK Drutskoy A Eidelman S Eiges V Fukunaga C Gabyshev N Garmash A Gershon T Golob B Guo R Hagner C Hara T Hazumi M Hojo T Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igaki T Igarashi Y Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki Y Jang HK Kang JH Kang JS 《Physical review letters》2003,90(20):201802
We report the first observation of the charmless hyperonic B decay, B0-->pLambda(pi)(-), using a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. The measured branching fraction is B(B0-->pLambda(pi)(-))=(3.97(+1.00)(-0.80)+/-0.56)x10(-6). Searches for B0-->pLambda(K)- and pSigma(0)pi(-) yield no significant signals and we set 90% confidence-level upper limits of B(B0-->pLambda(K)-)<8.2x10(-7) and B(B0-->pSigma(0)pi(-))<3.8x10(-6). 相似文献
74.
Laxmidhar?Behera Indrani?Kar Avshalom C.?ElitzurEmail author 《Foundations of Physics Letters》2005,18(4):357-370
A theoretical quantum neural network model is proposed using a nonlinear Schrödinger wave equation. The model proposes that there exists a nonlinear Schrödinger wave equation that mediates the collective response of a neural lattice. The model is used to explain eye movements when tracking moving targets. Using a recurrent quantum neural network(RQNN) while simulating the eye tracking model, two very interesting phenomena are observed. First, as eye sensor data is processed in a classical neural network, a wave packet is triggered in the quantum neural network.This wave packet moves like a particle. Second, when the eye tracks a fixed target, this wave packet moves not in a continuous but rather in a discrete mode. This result reminds one of the saccadic movements of the eye consisting of ‘jumps’ and ‘rests’. However, such a saccadic movement is intertwined with smooth pursuit movements when the eye has to track a dynamic trajectory. In a sense, this is the first theoretical model explaining the experimental observation reported concerning eye movements in a static scene situation. The resulting prediction is found to be very precise and efficient in comparison to classical objective modeling schemes such as the Kalman filter. 相似文献
75.
The concentration dependence of the reststrahl absorption in various mixed crystals exhibiting one, two and mixed mode behaviour
is investigated using the coherent potential approximation (cpa). The phonon Green’s function, the impurity mode frequencies and the strength of absorption are calculated in the Einstein
model from the generalizedcpa proposed by Tripathi and Behera which takes into account both mass and force constant changes. The introduction of a phenomenological
concentration dependence of the force constant change parameter is shown to provide a satisfactory explanation of the concentration
dependence of the experimental data for the twenty mixed crystal systems analysed. It is conjectured that the nearest neighbour
force constant of an impurity atom substituted at a host site is very much different from that of a perfect crystal consisting
of these impurity atoms and that both these play an important role in determining the one, two and mixed mode behaviour of
the mixed crystals. 相似文献
76.
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
77.
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
78.
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
79.
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
80.
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