共查询到20条相似文献,搜索用时 31 毫秒
1.
The Low Temperature Polarised Electronic Spectra of Some Tetragonal Nickel(II) Haloacetate Complexes
We have recently reported the single crystal electronic spectra of some substituted ethylenediamine complexes of nickel(II), discussing both cis (1) and trans (2) examples. We have also reported data for their cobalt(II) analogs (3). These were analysed using the Normalised Spherical Harmonic Hamiltonian (NSH) (4) and the Orbital Angular Overlap Model (OAM) (5) approaches. We have 相似文献
2.
We synthesized tunable far-infrared radiation at frequencies higher than 9 THz (300 cm (-1)) by mixing CO(2) laser, (15)NH(3) laser, and microwave radiation in a W-Co metal-insulator-metal diode. We used this farinfrared radiation to accurately measure torsion-rotation transitions of CH(3)OH in the 8-9-THz region. We also measured the frequency of the aP(7, 3) (15)NH(3) laser transition. 相似文献
3.
Browder TE Li Y Rodriguez JL Yamamoto H Bergfeld T Eisenstein BI Ernst J Gladding GE Gollin GD Hans RM Johnson E Karliner I Marsh MA Palmer M Plager C Sedlack C Selen M Thaler JJ Williams J Edwards KW Janicek R Patel PM Sadoff AJ Ammar R Bean A Besson D Davis R Kwak N Zhao X Anderson S Frolov VV Kubota Y Lee SJ Mahapatra R O'Neill JJ Poling R Riehle T Smith A Stepaniak CJ Urheim J Ahmed S Alam MS Athar SB Jian L Ling L Saleem M Timm S Wappler F Anastassov A Duboscq JE Eckhart E Gan KK Gwon C 《Physical review letters》2001,86(14):2950-2954
We report results of a search for B-->tau(nu) in a sample of 9.7 x 10(6) charged B meson decays. We exclusively reconstruct the companion B decay to suppress background. We set an upper limit on the branching fraction B(B-->tau(nu))<8.4 x 10(-4) at 90% confidence level. We also establish B(B+/--->K+/-nu(nu))<2.4 x 10(-4) at 90% confidence level. 相似文献
4.
Artuso M Boulahouache C Blusk S Butt J Dambasuren E Dorjkhaidav O Li J Menaa N Mountain R Muramatsu H Nandakumar R Redjimi R Sia R Skwarnicki T Stone S Wang JC Zhang K Csorna SE Bonvicini G Cinabro D Dubrovin M Bornheim A Pappas SP Weinstein AJ Rosner JL Briere RA Chen GP Ferguson T Tatishvili G Vogel H Watkins ME Adam NE Alexander JP Berkelman K Cassel DG Crede V Duboscq JE Ecklund KM Ehrlich R Fields L Galik RS Gibbons L Gittelman B Gray R Gray SW Hartill DL Heltsley BK Hertz D Hsu L Jones CD 《Physical review letters》2005,94(3):032001
We have studied the inclusive photon spectra in Upsilon(2S) and Upsilon(3S) decays using a large statistics data sample obtained with the CLEO III detector. We present the most precise measurements of electric dipole (E1) photon transition rates and photon energies for Upsilon(2S) --> gammachi(bJ)(1P) and Upsilon(3S) --> gammachi(bJ)(2P) (J = 0, 1, 2). We measure the rate for a rare E1 transition Upsilon(3S) --> gammachi(b0)(1P) for the first time. We also set upper limits on the rates for the hindered magnetic dipole (M1) transitions to the eta(b)(1S) and eta(b)(2S) states. 相似文献
5.
We design and fabricate ultra-high-quality (Q) photonic nanocavities in a symmetrically glass-clad silicon (Si) two-dimensional (2D) photonic crystal (PhC) structure. We theoretically investigate the dependence of the refractive index of the glass on the Q factors for asymmetric and symmetric structures. We show that the index-symmetric distribution of the glass is a critical factor to realize ultrahigh Q factors for glass-clad 2D PhC structures. We fabricate symmetrically glass-clad Si PhC nanocavities and achieve a record Q factor of 1×10(6), comparable with the highest Q factors of nanocavities in air-bridge structures. 相似文献
6.
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
7.
Valentí R Saha-Dasgupta T Alvarez JV Pozgajcic K Gros C 《Physical review letters》2001,86(23):5381-5384
We determine the electronic structure of the one-dimensional spin- 1 / 2 Heisenberg compound gamma-LiV2O5, which has two inequivalent vanadium ions, V(1) and V(2), via density-functional calculations. We find a relative V(1)-V(2) charge ordering of roughly 70:30. We discuss the influence of the charge ordering on the electronic structure and the magnetic behavior. We give estimates of the basic hopping matrix elements and compare with the most studied (alpha)'-NaV2O5. 相似文献
8.
We review theoretical and experimental work on colloidal interactions in two-dimensional (2D) nematic emulsions. We pay particular
attention to the effects of (i) the nematic elastic constants, (ii) the size of the colloids, and (iii) the boundary conditions
at the particles and the container. We consider the interactions between colloids and fluid (deformable) interfaces and the
shape of fluid colloids in smectic-C films. 相似文献
9.
《中国光学快报(英文版)》2020,(4)
We experimentally demonstrated optical wireless power transfer(OWPT) using a near-infrared laser diode(LD)as the optical power transmitter.We considered a photovoltaic(PV) cell and a photodiode(PD) as the optical power receivers.We investigated the characteristics of the LD,PD,and PV cell in order to determine the optimum operating condition from the viewpoint of transfer efficiency.We also experimentally demonstrated a whole system optimization process to maximize the DC-to-DC transfer efficiency of the OWPT.Our experimental results showed that the optimization process can improve the OWPT efficiency by up to 48%. 相似文献
10.
T.C. Yang 《Physics letters. [Part B]》1976,65(4):358-362
We present a systematic analysis of hadronic neutral currents in low energy neutrino reactions applicable to SU(2) ? U(1) models with any number of quarks. We point out a relation to determine the Weinberg angle independent of the models for the heavy quarks. We discuss the constraints of atomic neutral current experiments on the SU(2) ? U(1) gauge models. 相似文献
11.
We present a general solution to the long-standing problem of determining the masses of pair-produced, semi-invisibly decaying particles at hadron colliders. We define two new transverse kinematic variables M(CT)(⊥) and M(CT)(∥), which are suitable one-dimensional projections of the contransverse mass M(CT). We derive analytical formulas for the boundaries of the kinematically allowed regions in the (M(CT)(⊥),M(CT)(∥)) and (M(CT)(⊥),M(CT)) parameter planes and introduce suitable variables D(CT)(∥) and D(CT) to measure the distance to those boundaries on an event per event basis. We show that the masses can be reliably extracted from the end-point measurements of M(CT)(⊥)(max) and D(CT)(min) (or D(CT)(∥)(min)). We illustrate our method with dilepton tt events at the LHC. 相似文献
12.
Aaltonen T Adelman J Akimoto T Albrow MG Alvarez González B Amerio S Amidei D Anastassov A Annovi A Antos J Aoki M Apollinari G Apresyan A Arisawa T Artikov A Ashmanskas W Attal A Aurisano A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Beauchemin PH Bedeschi F Bednar P Behari S Bellettini G Bellinger J Belloni A Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Bizjak I Blair RE Blocker C 《Physical review letters》2008,101(12):121801
We search for pair production of doubly charged Higgs particles (H+/- +/-) followed by decays into electron-tau (etau) and muon-tau (mutau) pairs using data (350 pb(-1) collected from [over]pp collisions at sqrt[s]=1.96 TeV by the CDF II experiment. We search separately for cases where three or four final-state leptons are detected, and combine results for exclusive decays to left-handed etau (mutau) pairs. We set an H+/- +/- lower mass limit of 114(112) GeV/c(2) at the 95% confidence level. 相似文献
13.
Li J Zhang ZP Schwartz AJ Abe K Abe K Aihara H Akatsu M Asano Y Aushev T Bakich AM Bay A Bedny I Bitenc U Bizjak I Bondar A Bozek A Bracko M Brodzicka J Browder TE Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dong LY Drutskoy A Eidelman S Eiges V Enari Y Fang F Fratina S Gabyshev N Garmash A Gershon T Gokhroo G Haba J Hayasaka K Hayashii H Hazumi M Higuchi T Hokuue T Hoshi H Hou S Hou WS Iijima T Imoto A Inami K Itoh R Iwasaki M 《Physical review letters》2005,94(7):071801
We have searched for mixing in the D(0)-D (0) system by measuring the decay-time distribution of D(0) --> K(+) pi(-) decays. The analysis uses 90 fb(-1) of data collected by the Belle detector at the KEKB e(+) e(-) collider. We fit the decay-time distribution for the mixing parameters x' and y' and also for the parameter R(D), which is the ratio of the rate for the doubly-Cabibbo-suppressed decay D(0)--> K+ pi(-) to that for the Cabibbo-favored decay D(0)--> K-pi(+). We do these fits both assuming CP conservation and allowing for CP violation. We use a frequentist method to obtain a 95% C.L. region in the x'(2) - y' plane. Assuming no mixing, we measure R(D) = (0.381 +/- 0.017(+0.008)(-0.016))%. 相似文献
14.
We report the infrared (IR) response of Cu-O chains in the high-T(c) superconductor YBa(2)Cu(3)O(y) over the doping range spanning y=6.28-6.75. We find evidence for a power law scaling at mid-IR frequencies consistent with predictions for Tomonaga-Luttinger liquid, thus supporting the notion of one-dimensional transport in the chains. We analyze the role of coupling to the CuO2 planes in establishing metallicity and superconductivity in disordered chain fragments. 相似文献
15.
We present the results of ab initio modeling of Ge(111)-(2 × 1) surface in the presence of atomic vacancy in surface bilayer. We showed that simple crystal structure defect affects surface electronic structure to the extent comparable with the influence of doping atom. We demonstrated the strong difference of surface LDOS structure above surface defects of different kind. We have proved that spatial oscillations of LDOS exist around individual surface vacancy in the same tunneling bias range as in case of donor doping atom on Ge(111)-(2 × 1) surface. 相似文献
16.
Y. Shigeta Y. Kitagawa H. Nagao Y. Yoshioka J. Toyoda K. Nakasuji K. Yamaguchi 《Journal of Molecular Liquids》2001,90(1-3):69-74
We investigated singly ordered phases of the charge density were (CDW), spin density wave (SDW), and singlet superconductivity (SSC) for a pseudo one-dimensional proton and electron transfer (PET) system of quinhydrone crystal by means of the two band model. We performed band structure calculations of model systems, which are (i) the quinone and the p-hydroquinone model and (ii) two semiquinones model. We found that the model (i) exhibits an insulator and the model (ii) exhibits the SDW insulator. 相似文献
17.
We investigate anomalies ascribed to quantum entanglement phenomena recently reported in deep inelastc neutron scattering (DINS) measurements by an independent neutron technique on H(2)O/D(2)O mixtures. We performed transmission experiments to study several liquid H(2)O/D(2)O mixtures at room temperature in the epithermal energy range. We obtain the total cross sections of the mixtures, which are in agreement with the expected results according to the tabulated values within a 0.3% relative error. We observe no anomalies and stress the limitations of the validity of the data-processing procedures employed in the DINS experiments where the anomalies were reported. 相似文献
18.
Chen KF Hara K Hazumi M Higuchi T Miyabayashi K Nakahama Y Sumisawa K Tajima O Ushiroda Y Yusa Y Abe K Abe K Adachi I Aihara H Anipko D Arinstein K Aulchenko V Aushev T Aziz T Bakich AM Balagura V Banerjee S Barberio E Barbero M Bay A Belous K Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen WT Cheon BG Chistov R Choi SK Choi Y Choi YK Chuvikov A Cole S Dalseno J Danilov M Dash M Dragic J Drutskoy A Eidelman S Epifanov D Fratina S Garmash A 《Physical review letters》2007,98(3):031802
We present improved measurements of CP-violation parameters in B(0) --> phiK(0), eta(')K(0), KS(0)KS(0)KS(0) decays based on a sample of 535 x 10(6) BB pairs collected at the Upsilon(4S) resonance with the Belle detector at the KEKB energy-asymmetric e(+)e(-) collider. We obtain sin2phi1(eff)=+0.64+/-0.10(stat)+/-0.04(syst) for B(0) --> eta(')K(0), +0.50+/-0.21(stat)+/-0.06(syst) for B(0) --> phiK(0), and +0.30+/-0.32(stat)+/-0.08(syst) for B(0) --> KS(0)KS(0)KS(0) decays. We have observed CP violation in the B(0) --> eta(')K(0) decay with a significance of 5.6 standard deviations. We also perform an improved measurement of CP asymmetries in B(0) --> J/psiK(0) decays and obtain sin2phi1=+0.642+/-0.031(stat)+/-0.017(syst). 相似文献
19.
ZHU Shi-Lin GAO Chong-Shou 《理论物理通讯》2006,46(2):291-293
We point out that the large pp^- coupling of X(1835) and the suppression of the three-body strange final states strongly indicate that X(1835) may be a pp^- baryonium. We also point out that the branching ratio of X(1835) →ηππ should be bigger than that of X(1835) →η′ππ. We suggest BES search X(1835) in the ηππ channel Finally, X(1835) may be used a tetraquark generator if X(1835) is really established as a baryonium state. 相似文献
20.
Wang MH Berisso MC Christian DC Félix J Gara A Gottschalk E Gutiérrez G Hartouni EP Knapp BC Kreisler MN Lee S Markianos K Moreno G Reyes MA Sosa M Wehmann A Wesson D 《Physical review letters》2001,87(8):082002
We report the first observation of diffractively produced open charm in 800-GeV/c pp collisions of the type pp-->pD*X. We measure cross sections of sigma(diff)(D*+) = (0.185+/-0.044+/-0.054) (mu)b and sigma(diff)(D(*-)) = (0.174+/-0.034+/-0.029) (mu)b. Our measurements are based on 4.3x10(9) events recorded by FNAL E690 in the fixed-target run of 1991. We compare our results with previous fixed-target charm experiments. 相似文献