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951.
Acosta D Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arisawa T Arguin JF Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Bacchetta N Bachacou H Badgett W Barbaro-Galtieri A Barker GJ Barnes VE Barnett BA Baroiant S Barone M Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Ben-Haim E Benjamin D Beretvas A Bhatti A Binkley M Bisello D Bishai M Blair RE Blocker C Bloom K Blumenfeld B Bocci A 《Physical review letters》2005,94(10):101803
We present measurements of the lifetimes and polarization amplitudes for B(0)(s)-->J/psiphi and B(0)(d)-->J/psiK(*0) decays. Lifetimes of the heavy and light mass eigenstates in the B(0)(s) system are separately measured for the first time by determining the relative contributions of amplitudes with definite CP as a function of the decay time. Using 203+/-15 B(0)(s) decays we obtain tau(L) = (1.05(+0.16)(-0.13) +/- 0.02) ps and tau(H) = (2.07(+0.58)(-0.46) +/- 0.03) ps. Expressed in terms of the difference DeltaGamma(s) and average Gamma(s), of the decay rates of the two eigenstates, the results are DeltaGamma(s)/Gamma(s) = (65(+25)(-33) +/- 1)% and DeltaGamma(s) = (0.47(+0.19)(-0.24) +/- 0.01) ps(-1). 相似文献
952.
Aoki Y Wada Y Saitoh M Nomura R Okuda Y Nagato Y Yamamoto M Higashitani S Nagai K 《Physical review letters》2005,95(7):075301
Complex transverse acoustic impedance of the superfluid (3)He-B was measured at the frequencies of 10 to 80 MHz at 17.0 bar by a cw bridge method. The observed temperature dependence was well explained by the quasiclassical theory with random S-matrix model for a diffusive surface. The temperature dependence was influenced by pair breaking and by quasiparticle density of states at the surface, which was drastically modified from the bulk one by the presence of surface Andreev bound states. 相似文献
953.
Kuwahara K Iwasa K Kohgi M Kaneko K Metoki N Raymond S Méasson MA Flouquet J Sugawara H Aoki Y Sato H 《Physical review letters》2005,95(10):107003
We report inelastic neutron scattering experiments performed to investigate the low energy magnetic excitations on single crystals of the heavy-fermion superconductor PrOs(4)Sb(12). The observed excitation clearly softens at a wave vector Q=(1,0,0), which is the same as the modulation vector of the field-induced antiferro-quadrupolar ordering, and its intensity at Q=(1,0,0) is smaller than that around the zone center. This result directly evidences that this excitonic behavior is derived mainly from nonmagnetic quadrupolar interactions. Furthermore, the narrowing of the linewidths of the excitations below the superconducting transition temperature indicates the close connection between the superconductivity and the excitons. 相似文献
954.
Abulencia A Acosta D Adelman J Affolder T Akimoto T Albrow MG Ambrose D Amerio S Amidei D Anastassov A Anikeev K Annovi A Antos J Aoki M Apollinari G Arguin JF Arisawa T Artikov A Ashmanskas W Attal A Azfar F Azzi-Bacchetta P Azzurri P Bacchetta N Bachacou H Badgett W Barbaro-Galtieri A Barnes VE Barnett BA Baroiant S Bartsch V Bauer G Bedeschi F Behari S Belforte S Bellettini G Bellinger J Belloni A Ben-Haim E Benjamin D Beretvas A Beringer J Berry T Bhatti A Binkley M Bisello D Bishai M 《Physical review letters》2005,95(25):252001
A search for new particles (X) that decay to electron or muon pairs has been performed using approximately 200 pb(-1) of pp collision data at (square root) s = 1.96 TeV collected by the CDF II experiment at the Fermilab Tevatron. Limits on sigma(pp --> X)BR (X --> ll) are presented as a function of dilepton invariant mass m(ll) > 150 GeV/c2, for different spin hypotheses (0, 1, or 2). The limits are approximately 25 fb for m(ll) > GeV/c2. Lower mass bounds for X from representative models beyond the standard model including heavy neutral gauge bosons are presented. 相似文献
955.
956.
Akio Sanpei Kiyokazu Ito Yukihiro Soga Jun Aoki Yasuhito Kiwamoto 《Hyperfine Interactions》2007,174(1-3):71-76
In the formation of vortical crystal structures of electrons, the distribution of background electrons works as a “cooler”
of randomly moving, intense vortices. We examine the supporting effect of background electrons to forming crystal structures
from the perspective of a reduction of the vortices’ random motion. 相似文献
957.
Y. Ma S. Ajimura K. Aoki M. Dairaku Y. Y. Fu H. Fujioka T. Fukuda K. Futatsukawa K. Hosomi W. Imoto M. Kawai Y. Kakiguchi S. Kinoshita T. Koike N. Maruyama M. Mimori S. Minami Y. Miura K. Miwa Y. Miyagi T. Nagae D. Nakajima H. Noumi K. Shirotori T. Suzuki T. Takahashi T. N. Takahashi H. Tamura K. Tanida N. Terada A. Toyoda K. Tsukada M. Ukai S. H. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2007,33(3):243-246
In this paper, a preliminary result from the latest hypernuclear γ -ray spectroscopy experiment (KEK-E566) is presented together
with a short discussion. The experiment was performed at the KEK-PS K6 beam line in 2005. In this experiment, the 12C(π+, K
+)12
ΛC reaction was employed to populate 12
ΛC/11
ΛB hypernuclei. A germanium detector array, Hyperball2, was constructed to detect γ -rays emitted from the hypernuclei produced.
Three hypernuclear γ -ray peaks were observed and assigned. 相似文献
958.
We studied a method of estimating the number of contacts in a solid dosage form using thermal analysis. Ibuprofen (IB) and Ethenzamide (ET) were used as model actives. IB and ET were granulated and sieved with each other. We prepared mixtures of IB and ET using different diameter granules. The number of contacts between the samples was calculated by the expression method of Ouchiyama and Tanaka. By thermal analysis, we measured the quantity of endotherm up to 60-63 degrees C from 56 degrees C. The quantity of endotherm up to 61 degrees C from 56 degrees C was in good proportion to the number of contacts calculated by the expression. 相似文献
959.
We perform a Wilson Chiral Perturbation Theory (WChPT) analysis of quenched twisted mass lattice data. The data were generated
by two independent groups with three different choices for the critical mass. For one choice, the so-called pion mass definition,
one observes a strong curvature for small quark masses in various mesonic observables (“bending phenomenon”). Performing a
combined fit to the next-to-leading (NLO) expressions, we find that WChPT describes the data very well and the fits provide
very reasonable values for the low-energy parameters. 相似文献
960.
Novel materials processing by a multiwavelength excitation process using F(2) and KrF excimer lasers for high-efficiency and high-speed refractive-index modification of fused silica is demonstrated. We find this process to be essentially superior to single-wavelength F(2) -laser processing: The multiwavelength excitation process achieves more than twice the diffraction efficiency of fused silica modified by a F(2) laser at the same total number of photons in each irradiated laser beam supplied to the fused-silica substrate. This superiority is attributed to a resonance-photoionization-like process based on excited-state absorption. 相似文献