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181.
Walsh MS Xu LH Lees RM Mukhopadhyay I Moruzzi G Winnewisser BP Albert S Butler RA DeLucia FC 《Journal of Molecular Spectroscopy》2000,204(1):60-71
New millimeter-wave and microwave measurements for CH(3)OD have been combined with previous literature data and with an extended body of Fourier transform far-infrared observations in a full global analysis of the first two torsional states (v(t) = 0 and 1) of the ground vibrational state. The fitted CH(3)OD data set contained 564 microwave and millimeter-wave lines and 4664 far-infrared lines, representing the most recent available information in the quantum number ranges J = 20 and K = 15. A 53-parameter converged global fit was achieved with an overall weighted standard deviation of 1.060, essentially to within the assigned measurement uncertainties of +/-100 kHz for almost all of the microwave and millimeter-wave lines and +/-6 MHz for the far-infrared lines. The new parameters for CH(3)OD are compared to previous results obtained for the (12)CH(3)OH, (13)CH(3)OH, and CD(3)OH isotopomers over the same quantum number ranges using the identical fitting program. Strong asymmetry-induced coupling between the accidentally near-degenerate 0E and -1E v(t) = 0 substates is successfully modeled by the fit. Copyright 2000 Academic Press. 相似文献
182.
R.M. Lees Li-Hong Xu B.P. Winnewisser M. Lock 《Journal of Molecular Spectroscopy》2007,243(2):168-181
Fourier transform infrared spectra of CH3OH from 930-1650 cm−1 have been analyzed to reveal details of the rotation-torsion-vibration energy manifold of the CO-stretching, CH3-rocking, OH-bending and CH3-deformation modes and their torsional combination states. Mapping of the upper-state term values as a function of the rotational quantum number J has shown the locations of numerous substate crossing resonances that give rise to J-localized spectral perturbations and substate mixing and thereby create “doorways” for collision-induced population transfer among the different modes. Other near-degenerate substates are more globally mixed over a wide range of J, corresponding to “corridors” of doorways. Where both partner substates in a doorway resonance have been identified, the perturbations have been analyzed to find estimates of the interaction matrix elements and the degree of mixing between the coupled states. Many of the resonances are between substates of differing torsional quantum number, highlighting the importance of torsion in generating the doorway channels and enhancing intermode vibrational population transfer. 相似文献
183.
Aubert B Barate R Boutigny D Couderc F Gaillard JM Hicheur A Karyotakis Y Lees JP Tisserand V Zghiche A Palano A Pompili A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Borgland AW Breon AB Brown DN Button-Shafer J Cahn RN Charles E Day CT Gill MS Gritsan AV Groysman Y Jacobsen RG Kadel RW Kadyk J Kerth LT Kolomensky YG Kukartsev G LeClerc C Levi ME Lynch G Mir LM Oddone PJ Orimoto TJ Pripstein M Roe NA Ronan MT Shelkov VG Telnov AV Wenzel WA Ford K Harrison TJ Hawkes CM 《Physical review letters》2004,92(6):061801
We present measurements of branching fractions and charge asymmetries for seven B-meson decays with an eta, eta', or omega meson in the final state. The data sample corresponds to 89x10(6) BB pairs produced from e(+)e(-) annihilation at the Upsilon(4S) resonance. We measure the following branching fractions in units of 10(-6): B(B+-->eta pi(+))=5.3+/-1.0+/-0.3, B(B+-->eta K+)=3.4+/-0.8+/-0.2, B(B0-->eta K0)=2.9+/-1.0+/-0.2 (<5.2, 90% C.L.), B(B+-->eta(')pi(+))=2.7+/-1.2+/-0.3 (<4.5, 90% C.L.), B(B+-->omega pi(+))=5.5+/-0.9+/-0.5, B(B+-->omega K+)=4.8+/-0.8+/-0.4, and B(B0-->omega K0)=5.9(+1.6)(-1.3)+/-0.5. The charge asymmetries are A(ch)(B+-->eta pi(+))=-0.44+/-0.18+/-0.01, A(ch)(B+-->eta K+)=-0.52+/-0.24+/-0.01, A(ch)(B+-->omega pi(+))=0.03+/-0.16+/-0.01, and A(ch)(B+-->omega K+)=-0.09+/-0.17+/-0.01. 相似文献
184.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Tico JG Grauges E Lopez L Palano A Eigen G Ofte I Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Pegna DL Lynch G Mir LM Orimoto TJ Pripstein M Roe NA Ronan MT Tackmann K Wenzel WA del Amo Sanchez P Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Schroeder T Steinke M Cottingham WN Walker D Asgeirsson DJ 《Physical review letters》2007,99(6):062001
We present an analysis of inclusive Omega(c)(0) baryon production and decays in 230.5 fb(-1) of data recorded with the BABAR detector. Omega(c)(0) baryons are reconstructed in four final states (Omega(-)pi(+), Omega(-)pi(+)pi(0), Omega(-)pi(+)pi(+)pi(-), Xi(-)K(-)pi(+)pi(+)) and the corresponding ratios of branching fractions are measured. We also measure the momentum spectrum in the e(+)e(-) center-of-mass frame. From the spectrum, we observe Omega(c)(0) production from B decays and in cc events, and extract the two rates of production. 相似文献
185.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Grauges E Palano A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Pegna DL Lynch G Mir LM Orimoto TJ Osipenkov I Pripstein M Roe NA Ronan MT Tackmann K Wenzel WA Sanchez Pdel A Barrett M Harrison TJ Hart AJ Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Peters K 《Physical review letters》2007,98(11):111801
We search for the decays B(0) --> rho(0)rho(0), B(0) --> rho(0)f(0)(980), and B(0) --> f(0)(980)f(0)(980) in a sample of about 384 x 10(6) Upsilon(4S) --> BB[over] decays collected with the BABAR detector at the PEP-II asymmetric-energy e(+)e(-) collider at Stanford Linear Accelerator Center. We find evidence for B(0) --> rho(0)rho(0) with 3.5 sigma significance and measure the branching fraction B = (1.07 +/- 0.33 +/- 0.19) x 10(-6) and longitudinal polarization fraction f(L) = 0.87 +/- 0.13 +/- 0.04, where the first uncertainty is statistical, and the second is systematic. The uncertainty on the Cabibbo-Kobayashi-Maskawa quark-mixing matrix unitarity angle alpha due to penguin contributions in B --> rho rho decays is 18 degrees at the 1 sigma level. We also set upper limits on the B(0) --> rho(0)f(0)(980) and B(0) --> f(0)(980)f(0)(980) decay rates. 相似文献
186.
Aubert B Bona M Boutigny D Couderc F Karyotakis Y Lees JP Poireau V Tisserand V Zghiche A Grauges E Palano A Chen JC Qi ND Rong G Wang P Zhu YS Eigen G Ofte I Stugu B Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Charles E Gill MS Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Pegna DL Lynch G Mir LM Orimoto TJ Pripstein M Roe NA Ronan MT Wenzel WA Sanchez Pdel A Barrett M Ford KE Harrison TJ Hart AJ Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M 《Physical review letters》2007,98(5):051801
We perform an amplitude analysis of the decays B(0)-->phiK*(2)(1430)(0), phiK*(892)(0), and phi(Kpi)(0)(S-wave) with a sample of about 384x10(6) BB[over ] pairs recorded with the BABAR detector. The fractions of longitudinal polarization f(L) of the vector-tensor and vector-vector decay modes are measured to be 0.853(-0.069+0.061)+/-0.036 and 0.506+/-0.040+/-0.015, respectively. Overall, twelve parameters are measured for the vector-vector decay and seven parameters for the vector-tensor decay, including the branching fractions and parameters sensitive to CP violation. 相似文献
187.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Ronan MT Tackmann K Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Held T Koch H Lewandowski B Pelizaeus M Schroeder T Steinke M Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG 《Physical review letters》2007,98(21):211803
We observe evidence for D(0)-D(0) mixing by measuring the difference in the apparent lifetime when a D(0) meson decays to the CP eigenstates K(+)K(-) and pi(+)pi(-) and when it decays to the final state K(-)pi(+). We find the relative difference of the lifetimes y(CP) to be [1.31+/-0.32(stat)+/-0.25(syst)]%, 3.2 standard deviations from zero. We also search for a CP asymmetry between D(0) and D(0) decays; no evidence for CP violation is found. These results are based on 540 fb(-1) of data recorded by the Belle detector at the KEKB e(+)e(-) collider. 相似文献
188.
Aubert B Bona M Boutigny D Karyotakis Y Lees JP Poireau V Prudent X Tisserand V Zghiche A Garra Tico J Grauges E Lopez L Palano A Pappagallo M Eigen G Stugu B Sun L Abrams GS Battaglia M Brown DN Button-Shafer J Cahn RN Groysman Y Jacobsen RG Kadyk JA Kerth LT Kolomensky YG Kukartsev G Lopes Pegna D Lynch G Mir LM Orimoto TJ Osipenkov IL Ronan MT Tackmann K Tanabe T Wenzel WA Del Amo Sanchez P Hawkes CM Watson AT Koch H Schroeder T Walker D Asgeirsson DJ Cuhadar-Donszelmann T Fulsom BG Hearty C 《Physical review letters》2007,99(25):251803
A search for the neutrinoless, lepton-flavor violating decay of the tau lepton into three charged leptons has been performed using 376 fb{-1} of data collected at an e{+}e{-} center-of-mass energy around 10.58 GeV with the BABAR detector at the SLAC PEP-II storage rings. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (4-8)x10{-8} at 90% confidence level. 相似文献
189.
This study investigates the use of high resolution 1H NMR as a suitable alternative to the standard chromatographic method for the determination of adulteration of orange juice (Citrus sinensis) with grapefruit juice (Citrus paradisi) based on flavonoid glycoside content. Fifty-nine orange juices (OJ), 23 grapefruit juices (GJ) and 10 blends (OG), obtained from local retail outlets were used to assess the performance of the 1H NMR method. The work presented here introduces the Evolving Window Zone Selection (EWZS) function that holds promise for the automatic detection of spectral regions tailored to discriminate predefined groups. This technique was applied on the pre-processed 1H NMR spectra of the 92 juices. Independent Component Analysis (ICA) is a good alternative to Principal Component Analysis (PCA) for recovering linearly-mixed unobserved multidimensional independent signals and has been used in this study to build supervised models that classify the samples into three categories, OJ, GJ, OG. The regions containing the known flavonoid glycoside markers were selected as well as another zone containing the signals of sucrose, α-glucose and other components that were tentatively attributed. ICA was applied on three different groups of selected variables and showed good results for both discrimination and interpretation of the signals. Up to 97.8% of the juices were correctly attributed. This method gave better results than the commonly used PCA method. In addition, the time required to carry out the 1H NMR analysis was less than half the time of the standard chromatographic method. 相似文献
190.
In this work, a Control Volume Radial Basis Function technique (CV-RBF) is adapted to solve ground water flow in the saturated
zone of the semi-confined aquifer. The CV-RBF method differs from classical CV methods in the way that the flux at the cell
surfaces is computed. A local RBF interpolation of the field variable is performed at the centres of the cell being integrated
and its neighbours. This interpolation is then used to reconstruct the solution and its gradient in the integration points
which support the flux computation. In addition, it is required that such interpolation satisfies the governing equation in
a certain number of points placed around the cell centres. In this way, the local interpolations become equivalent to local
boundary-value problems. The CV-RBF method is combined with a local remeshing technique in order to track the phreatic surface,
where the gradients required to satisfy the kinematic condition are computed by the same local RBF interpolations used for
the flux computation. The proposed numerical approach is validated in a series of three-dimensional groundwater flow problems
where the operations of recharging and extracting water from a semi-confined aquifer are modelled. 相似文献