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61.
62.
63.
N. Adachi 《Journal of Optimization Theory and Applications》1973,11(6):590-604
Generalized variable-metric algorithms presented in Ref. 1 produce a unique search direction independently of parameters in the algorithms under several conditions. They generate a unique sequence of minimizing points for the given initial conditions if the objective function is quadratic. 相似文献
64.
Clean surfaces of GaAs and GaP were studied by field-ion microscope (FIM). Field-ion images with ordered surfaces were first obtained in pure hydrogen, neon-50% hydrogen and pure neon gases at 78 K, by using channeltron electron multiplier arrays (CEMA). The field-ion images of GaAs were quite similar to those of GaP with respect to the surface structure and the image contrast. They showed the anisotropies of the ion emission and the surface structure between the [111] and orientations. Ring steps expected from a spherical surface were observed on the (111) and {100} planes, but not on the and {110} planes. The regional brightness of the FIM patterns was discussed in terms of the Knor and Müller model and the atomic and electronic structures of the surface. The image field of these crystals was much lower than that of metals usually used in FIM. For example, the image field strength for the hydrogen and GaAs system was about 1.1 V/Å. The reduction of the field necessary to image was also discussed in terms of the field penetration effect. 相似文献
65.
Properties of the levels in 112In have been studied with the reaction 112Cd(p, nγ)112In. The level scheme of 112In below 1300 keV was constructed from the γ-ray excitation functions and γγ coincidences. In 112In, 22 excited states were observed and spins and parities of 8 excited states were newly assigned or restricted by comparing the measured angular distributions and linear polarizations of the deexciting γ-rays as well as the excitation functions of the residual levels with the predictions of the statistical compound nucleus model. Possible configurations of the low-lying levels are discussed in terms of their decay properties and the systematics of the excited states in the neighbouring doubly odd In isotopes. 相似文献
66.
The magnetic susceptibility of RB2C2 has been measured in the temperature range of 3–300 K. Curie-Weiss fits to the susceptibilities led to effective moments in agreement with those expected for R3+ ions. The RB2C2 (R = Ce, Nd, Sm, Gd, Tb, Er, and Tm) compounds are antiferromagnetic. Metamagnetic transitions at low fields were observed for CeB2C2 and TbB2C2. The compounds, DyB2C2 and HoB2C2, are ferromagnets with complex magnetic structures. Praseodymium borocarbide becomes a Van Vleck paramagnet at low temperature. The magnetic ordering temperatures of these compounds are discussed in terms of their crystal structure and the RKKY theory. 相似文献
67.
Majumder G Abe K Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bahinipati S Bakich AM Banerjee S Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS 《Physical review letters》2005,95(4):041803
We report evidence for B(0) --> D(0)D(-) and the first observation of the decay modes B(-) --> D(0)D(-) and B(-) --> D(0)D(*-) based on a sample of 152 x 10(6) BB events collected by the Belle detector at KEKB. The branching fractions for B(0) --> D(+) D(-), B--->D(0)D(-), and B--> D(0)D(*-) are found to be (1.91 +/- 0.51 +/- 0.30) x10(-4), (4.83 +/- 0.78 +/- 0.58) x 10(-4), and (4.57 +/- 0.71 +/- 0.56) x 10(-4), respectively. Charge asymmetries in the B---> D(0)D(-) and B(-) --> D(0)D(*-) channels are consistent with zero. 相似文献
68.
Sumisawa K Ushiroda Y Hazumi M Abe K Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bakich AM Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Gorisek A Haba J Hara K Hara T Hayashii H Higuchi T Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A Inami K Ishikawa A 《Physical review letters》2005,95(6):061801
We present a measurement of CP-violation parameters in the B0 --> K(s)0K(s)0K(s)0 decay based on a sample of 275 x 10(6) BB pairs collected at the upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e+e- collider. One neutral B meson is fully reconstructed in the decay B0 --> K(s)0K(s)0K(s)0, and the flavor of the accompanying B meson is identified from its decay products. CP-violation parameters are obtained from the asymmetry in the distributions of the proper-time interval between the two B decays: S = +1.26 +/- 0.68(stat) +/- 0.20(syst) and [symbol: see text] = +0.54 +/- 0.34(stat) +/- 0.09(syst). 相似文献
69.
Abe K Abe K Adachi I Aihara H Akatsu M Anipko D Asano Y Aushev T Aziz T Bahinipati S Bakich AM Banerjee S Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Dalseno J Danilov M Dash M Drutskoy A Eidelman S Eiges V Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Golob B Haba J Hastings NC Hayasaka K Hayashii H Hazumi M Higuchi T Hinz L Hokuue T Hoshi Y Hou S Hou WS Iijima T Imoto A 《Physical review letters》2005,94(22):221805
We report on the first observation of D0/1(2420)-->D0pi- pi+ and D+/1(2420-->D+ pi- pi+ decays (where the contribution from the dominant known D1-->D*pi decay mode is excluded) in the B- -->D0/1pi-) and (-)B0-->D+/1pi- decays, respectively. The observation is based on 15.2 x 10(7) B(-)B events collected with the Belle detector at the KEKB collider. We also set 90% confidence level upper limits for the branching fractions of the four following decays: B- -->D0/1pi-, D01-->D(*0)pi- pi+, (-)B0-->D+/1pi-, D+/1-->D(*+) pi- pi+, B- -->D(*0)2(2460)pi-, D(*0)2 -->D(*0) pi- pi+, (-)B0-->D(*+)2(2460)pi-, D(*+)2-->D(*+)pi- pi+. 相似文献
70.
Choi SK Olsen SL Abe K Abe K Adachi I Aihara H Asano Y Bahinipati S Bakich AM Ban Y Bedny I Bitenc U Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang MC Chang P Chen A Chen WT Cheon BG Chistov R Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Drutskoy A Eidelman S Enari Y Fang F Fratina S Gabyshev N Gershon T Gokhroo G Golob B Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T Hoshi Y Hou S Hou WS Hsiung YB Iijima T Imoto A Inami K Ishikawa A Iwasaki M 《Physical review letters》2005,94(18):182002
We report the observation of a near-threshold enhancement in the omegaJ/psi invariant mass distribution for exclusive B-->KomegaJ/psi decays. The results are obtained from a 253 fb(-1) data sample that contains 275 x 10(6) BB pairs that were collected near the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric energy e(+)e(-) collider. The statistical significance of the omegaJ/psi mass enhancement is estimated to be greater than 8sigma. 相似文献