Mossbauer Spectra of Iron Sulfide Fe1-xS

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Anisotropy of Electrical Transport and Superconductivity in Metal Chains of Nb2Se3

In this work we have shown bulk superconductivity and studied the anisotropy in both the normal and superconducting states in quasi-1D conductor Nb2Se3. Electron - electron Umklapp scattering dominates electronic transport along the direction of Nb metal chains as well as perpendicular to it. The superconducting state is rather anisotropic with possible multi - band features.Comment: 5 pages, 5 figure

Search for the Electric Dipole Moment of the tau Lepton

We have searched for a CP violation signature arising from an electric dipole moment (d_tau) of the tau lepton in the e+e- -> tau+tau- reaction. Using an optimal observable method and 29.5 fb^{-1} of data collected with the Belle detector at the KEKB collider at sqrt{s} = 10.58 GeV, we find Re(d_tau) = (1.15 +- 1.70) x 10^{-17} ecm and Im(d_tau) = (-0.83 +- 0.86) x 10^{-17} ecm and set the 95% confidence level limits -2.2 < Re(d_tau) < 4.5 (10^{-17}ecm) and -2.5 < Im(d_tau) < 0.8 (10^{-17}ecm).Comment: 15 pages, LaTeX, 21 figures, submitted to Phys. Lett.

Measurement of Branching Fractions for B→ηcK(∗)B\to \eta_c K^{(*)} Decays

We report measurements of branching fractions for charged and neutral $B\to \eta_c K$ decays where the $\eta_c$ meson is reconstructed in the $K_S^0 K^{\pm}\pi^{\mp}, K^+ K^- \pi^0, K^{*0} K^-\pi^+$ and $p \bar{p}$ decay channels. The neutral $B^0$ channel is a CP eigenstate and can be used to measure the CP violation parameter $\sin 2\phi_1$. We also report the first observation of the $B^0\to \eta_c K^{*0}$ mode. The results are based on an analysis of 29.1 fb$^{-1}$ of data collected by the Belle detector at KEKB.Comment: To appear in Physical Review Letter

Observation of the decay B^0->D+D*-

We report the first observation of the decay B^0->D+-D*-+ with the Belle detector at the KEKB e^+e^- collider operated at the Upsilon(4S) resonance. The sum of branching fractions B(B^0->D+D*-)+B(B^0->D-D*+) is measured to be (1.17+-0.26+0.22-0.25)x10^-3 using the full reconstruction method where both charmed mesons from B^0 decays are reconstructed. A consistent value ((1.48+-0.38+0.28-0.31)x10^-3) is obtained using a partial reconstruction technique that only uses the slow pion from the D*- ->bar D^0pi- decay and a fully reconstructed D+ to reconstruct the B^0.Comment: 10 pages, 3 figure

Study of Exclusive B decays to Charmed Baryons

Using 29.1fb-1 of data accumulated at the Upsilon(4S) with the Belle detector at KEKB, we have studied the decay modes B0bar->Lambda_c+ pbar pi+pi-, B- -> Lambda_c+ pbar pi-, and B0bar ->Lambda_c+ pbar. We report branching fractions of exclusive B decays to charmed baryons with four-, three- and two-body final states, including intermediate Sigma_c++ and Sigma_c0 states. We observed B0bar -> Sigma_c(2455)++pbar pi- for the first time with a branching fraction of (2.38+0.63-0.55+-0.41+-0.62)x10-4 and observed evidence for the two-body decay B- ->Sigma_c(2455)0 pbar with a branching fraction of (0.45+0.26-0.19+-0.07+-0.12)x10-4. We also set improved upper limits for the two-body decays B0bar -> Lambda_c+ pbar and B- -> Sigma_c(2520)0 pbar.Comment: accepted for publication in Phys. Rev.

Observation of B+- -> omega K+- Decay

We report the first observation of the charmless two-body mode $B^{\pm} \to \omega K^{\pm}$ decay, and a new measurement of the branching fraction for the $B^{\pm} \to \omega \pi^{\pm}$ decay. The measured branching fractions are ${\cal B} (B^{\pm} \to \omega K^{\pm}) = (9.2{}^{+2.6}_{-2.3}\pm 1.0) \times 10^{-6}$ and ${\cal B} (B^{\pm} \to \omega \pi^{\pm}) = (4.2{}^{+2.0}_{-1.8}\pm 0.5) \times 10^{-6}$. %and we set 90% confidence level upper limits of %${\cal B} (B^- \to \omega \pi^-) < 8.1\times 10^{-6}$. We also measure the partial rate asymmetry of $B^{\pm}\to\omega K^{\pm}$ decays and obtain ${\cal A}_{CP} = -0.21 \pm 0.28 \pm 0.03$. The results are based on a data sample of 29.4 fb$^{-1}$ collected on the $\Upsilon(4S)$ resonance by the Belle detector at the KEKB $e^{+} e^{-}$ collider.Comment: 5 pages, 4 figures, resubmitted to Phys. Rev. Let

Measurements of Branching Fractions and Decay Amplitudes in B-> J/\psi K^* decays

The branching fractions and the decay amplitudes of B -> J/psi K^* decays are measured in a 29.4/fb data sample collected with the Belle detector at the KEKB electron-positron collider. The decay amplitudes of helicity states of the J/psi K^* system are determined from the full angular distribution of the final state particles in the transversity basis. The branching fractions are measured to be (1.29\pm0.05\pm0.13) \times 10^{-3} for neutral mesons and (1.28\pm0.07\pm0.14) \times 10^{-3} for charged mesons. The measured longitudinal and transverse (perpendicular to the transversity plane) amplitudes are |A_0|^2 = 0.62\pm0.02\pm0.03 and |A_{\perp}|^2 = 0.19\pm0.02\pm0.03, respectively. The value of |A_{\perp}|^2 shows that the CP even component dominates in the B^0 \to J/\psi K^{*0}(K_S\pi^0) decay.Comment: 17 pages, 3 figures, 5 tables, to appear in Phys. Lett.