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61.
Esen S Schwartz AJ Adachi I Aihara H Arinstein K Aulchenko V Aushev T Aziz T Bakich AM Balagura V Barberio E Bay A Bischofberger M Bondar A Bozek A Bračko M Browder TE Chang MC Chang P Chen A Chen P Cheon BG Chiang CC Choi Y Dalseno J Dash M Doležal Z Drásal Z Drutskoy A Eidelman S Goldenzweig P Golob B Ha H Haba J Hara T Hayasaka K Higuchi T Hoshi Y Hou WS Hsiung YB Hyun HJ Iijima T Inami K Itoh R Iwabuchi M Joshi NJ Julius T Kang JH Kawasaki T Kichimi H Kim HJ Kim HO Kim JH Kim YJ Kinoshita K 《Physical review letters》2010,105(20):201802
We have made the first observation of B(s)(0)→D(s)(*)+ D(s)(*)- decays using 23.6 fb(-1) of data recorded by the Belle experiment running on the Υ(5S) resonance. The branching fractions are measured to be B(B(s)(0)→D(s)+ D(s)-)=(1.03(-0.32-0.25)(+0.39+0.26))%, B(B(s)(0)→D(s)(*±) D(s)(?))=(2.75(-0.71)(+0.83)±0.69)%, and B(B(s)(0)→D(s)*+ D(s)*-)=(3.08(-1.04-0.86)(+1.22+0.85))%; the sum is B[B(s)(0)→D(s)(*)+ D(s)(*)-]=(6.85(-1.30-1.80)(+1.53+1.79))%. Assuming B(s)(0)→D(s)(*)+ D(s)(*)- saturates decays to CP-even final states, the branching fraction determines the ratio ΔΓ(s)/cosφ, where ΔΓ(s) is the difference in widths between the two B(s)-B(s) mass eigenstates, and φ is a CP-violating weak phase. Taking CP violation to be negligibly small, we obtain ΔΓ(s)/Γ(s)=0.147(-0.030)(+0.036)(stat)(-0.041)(+0.042)(syst), where Γ(s) is the mean decay width. 相似文献
62.
A novel method is proposed for non-contact measurement of the distribution of electrostatic charge on a surface based on scanning the sample surface with a focused high frequency acoustic beam to excite movement of the sample surface. An electric field is induced by exciting a charged film-like object, and an electric field sensor measures it instead of an electrostatic field. The focused ultrasound waves are generated by controlling individually the phase of each 285 airborne ultrasound transducers. 相似文献
63.
Brodzicka J Palka H Adachi I Aihara H Aulchenko V Bakich AM Barberio E Bay A Bedny I Bitenc U Bondar A Bracko M Browder TE Chang MC Chang P Chen A Chen WT Cheon BG Chiang CC Chistov R Cho IS Choi SK Choi Y Dalseno J Danilov M Dash M Drutskoy A Eidelman S Gabyshev N Go A Gokhroo G Golob B Ha H Haba J Hara T Hayasaka K Hayashii H Hazumi M Heffernan D Hoshi Y Hou WS Hyun HJ Iijima T Ikado K Inami K Ishikawa A Ishino H Itoh R Iwasaki M Iwasaki Y Joshi NJ Kah DH Kang JH Kawai H Kawasaki T Kichimi H 《Physical review letters》2008,100(9):092001
We report the observation of a new DsJ meson produced in B+-->D0DsJ-->D0D0K+. This state has a mass of M=2708+/-9(-10)(+11) MeV/c2, a width Gamma=108+/-23(-31)(+36) MeV/c2 and a 1- spin-parity. The statistical significance of this observation is 8.4 sigma. The results are based on an analysis of 449 x 10(6) BB events collected at the Upsilon(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. 相似文献
64.
Isozaki Y Yao J Ji Z Saitoh M Kobayashi N Sakai H 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2008,84(8):344-353
The Capitanian (Late Guadalupian) Maokou Formation at Chaotian in northern Sichuan, South China, is composed mainly of shallow marine shelf carbonates deposited on the Tethyan side of South China. By detailed field mapping and scientific drilling, we newly found out unique fossil assemblages and a sharp lithologic change in the upper part of the Maokou Formation. The main part of the Maokou Formation (over 130 m thick) is composed of algal packstone with Wordian-Capitanian large-tested fusulines, rugose corals and other sessile benthos, whereas the Uppermost Member (13 m thick) is composed of black limy mudstone/chert with Capitanian offshore biota (ammonoids, radiolarians, and conodonts). The topmost Capitanian conodont zones are missing; however, the Maokou Formation is disconformably overlain by 260+/-4 Ma volcanic ash (Wangpo bed) and the Early Lopingian Wujiaping Formation with plant-bearing coaly mudstone and shallow marine carbonates (packstone). The newly identified facies change indicates that northern Sichuan has experienced rapid sea-level changes in the late Guadalupian, i.e., first a transgression in the mid-Capitanian and then a regression across the Guadalupian-Lopingian boundary. As the end-Guadalupian is characterized by a global regression, such a volatile sea-level fluctuation, in particular the sea-level rise, is unique to the Tethyan side of South China. The newly recognized relatively deep-water late Guadalupian sequence adds new paleo-environmental information and further provides a paleotectonic interpretation of the low-latitude eastern Tethyan margin immediately before the end-Guadalupian mass extinction. 相似文献
65.
Natural enantiomers of unique tricyclic sesquiterpenoids, valeriananoids A-C 1-3, have been synthesized starting from bicyclo[2.2.2]octane-2,5-dione derivative 11, which was obtained by diastereoselective catalytic domino Michael reaction of oxophorone 5 with 8-phenylmenthyl acrylate 10 by LDA or silica-gel-base (NMAP-Li). The tricyclic ring was closed selectively by intramolecular 6-endo-trig mode cyclization of the ketyl radical, which was generated from keto-allylether 25 by either lithium or sodium naphthalenide. 相似文献
66.
Fujiwara A Kameo Y Hoshi A Haraga T Nakashima M 《Journal of chromatography. A》2007,1140(1-2):163-167
Extraction chromatography with commercially available UTEVA resin (for uranium and tetravalent actinide) was applied for the separation of Th and U from control solutions prepared from a multi-element control solution and from sample solutions of solidified simulated waste. Thorium and U in control solutions with 1-5mol/dm(3) HNO(3) were extracted with UTEVA resin and recovered with a solution containing 0.1mol/dm(3) HNO(3) and 0.05mol/dm(3) oxalic acid to be separated from the other metallic elements. Extraction behavior of U in the sample solutions was similar to that in the control solutions, but extraction of Th was dependent on the concentration of HNO(3). Thorium was extracted from 5mol/dm(3) HNO(3) sample solutions but not from 1mol/dm(3) HNO(3) sample solutions. We conjecture that thorium fluoride formation interferes with extraction of Th. Addition of Al(NO(3))(3) and Fe(NO(3))(3), which have higher stability constant with fluoride ion than Th, does improve extractability of Th from 1mol/dm(3) HNO(3) sample solution. 相似文献
67.
68.
Asako Shimada-Fujiwara Akiko Hoshi Yutaka Kameo Mikio Nakashima 《Journal of chromatography. A》2009,1216(18):4125-4127
The dependence of Th recovery on hydrofluoric acid (HF) concentration in nitric acid (HNO3) solutions (1–5 mol/dm3) containing 1 × 10−6 mol/dm3 of Th and various concentrations of HF and the elution behavior were studied using a commercially available UTEVA (for uranium and tetravalent actinide) resin column. Thorium recovery decreased with an increase in HF concentration in the sample solutions. The concentration of HF at which Th recovery started to decrease was ∼1 × 10−4 mol/dm3 in 1 mol/dm3 HNO3 solution, ∼1 × 10−3 mol/dm3 in 3 mol/dm3 HNO3 solution, and ∼1 × 10−2 mol/dm3 in 5 mol/dm3 HNO3 solution. When Al(NO3)3 (0.2 mol/dm3) or Fe(NO3)3 (0.6 mol/dm3) was added as a masking agent for F− to the Th solution containing 1 × 10−1 mol/dm3 HF and 1 mol/dm3 HNO3, Th recovery improved from 1.4 ± 0.3% to 95 ± 5% or 93 ± 3%. Effective extraction of Th using UTEVA resin was achieved by selecting the concentration of HNO3 and/or adding masking agents such as Al(NO3)3 according to the concentration of HF in the sample solution. 相似文献
69.
The largest discrete octadecameric architecture based on a lanthanide ion has been found in the crystal structure of a La{N,N'-bis(2-pyridylmethyl)-N,N'-1,2-ethanediylbis(D-alaninate)} complex. 相似文献
70.
A new preparation method of 1,1,2,2-tetrafluoro-2-(trifluoroethenyloxy)-ethanesulfonyl fluoride (8) has been developed utilizing the unique performance of the imidazole protective group. Namely, the electrodonating character of the imidazole protective group on the sulfonyl group enables the formation of the novel intermediate monomer, which can be easily converted to 8 by the reaction with HF. 相似文献