Stability of Breakwater Armor Units against Tsunami Attacks

The design of breakwater armour units against tsunami attacks has received little attention in the past because of the comparative low frequency of these events and the rarity of structures designed specifically to withstand them. However, field surveys of recent events, such as the 2011 Great Eastern Japan Earthquake Tsunami and the 2004 Indian Ocean Tsunami, have shown flaws in the design of protection structures. During these extreme events, many breakwaters suffered partial or catastrophic damage. Although it is to be expected that most normal structures fail due to such high order events, practicing engineers need to possess tools to design certain important breakwaters that should not fail even during level 2 events. Research into the design of critical structures that only partially fail (i.e., “resilient” or “tenacious” structures) during a very extreme level 2 tsunami event should be prioritized in the future, and in this sense the present paper proposes a formula that allows the estimation of armour unit damage depending on the tsunami wave height

Measurements of Branching Fractions and Polarization in B > K^* rho Decays

We present results of a study of the charmless vector-vector decays B^0 -> K^{*0} rho^0 and B^+ ->K^{*0} rho^+. The results are based on a 140 fb^{-1} data sample collected by the Belle detector at the KEKB asymmetric e^+e^- collider. We obtain the branching fraction B(B^+ -> K^{*0} rho^+)=(6.6 +- 2.2(stat.) +- 0.8 (syst.)) x 10^{-6}, and set upper limits on the branching fractions B(B^0 -> K^{*0} rho^0) f_0(980) K^{*0})<5.2 x 10^{-6}. We also perform a helicity analysis of the rho and K^* vector mesons in the decay B^+ -> K^{*0} rho^+, and obtain the longitudinal polarization fraction R_0(B^+ -> K^{*0} rho^+)=0.50 +- 0.19(stat.)+0.05-0.07}(syst.).Comment: 11 pages, 4 figures, submitted to ICHEP04, Beijing, Chin

Measurements of the DsJD_{sJ} resonance properties

We report measurements of the properties of the $D_{sJ}^+(2317)$ and $D_{sJ}^+(2457)$ resonances produced in continuum $e^+ e^-$ annihilation near $\sqrt{s}=10.6 \mathrm{GeV}$. The analysis is based on an $86.9 \mathrm{fb^{-1}}$ data sample collected %at and 60 MeV below the $\Upsilon(4S)$ resonance with with the Belle detector at KEKB. We determine the masses to be $M(D_{sJ}^+(2317)) = 2317.2 \pm 0.5(\mathrm{stat}) \pm 0.9(\mathrm{syst}) \mathrm{MeV}/c^2$ and $M(D_{sJ}^+(2457))=2456.5 \pm 1.3(\mathrm{stat}) \pm 1.3(\mathrm{syst}) \mathrm{MeV}/c^2$. We observe the radiative decay mode $D_{sJ}^+(2457) \to D_s^+ \gamma$ and the dipion decay mode $D_{sJ}^+(2457) \to D_s^+ \pi^+ \pi^-$, and determine their branching fractions. No corresponding decays are observed for the $D_{sJ}(2317)$ state. These results are consistent with the spin-parity assignments of $0^+$ for the $D_{sJ}(2317)$ and $1^+$ for the $D_{sJ}(2457)$.Comment: 5 pages, 6 figures; Added content, updated and paper submitted to PR

Study of CP Violating Effects in Time Dependent B0(B0ˉ)→D(∗)∓π±B^0(\bar{B^0}) \to D^{(*)\mp}\pi^{\pm} Decays

We report measurements of time dependent decay rates for $B^0(\bar{B}^0) \to D^{(*)\mp}\pi^{\pm}$ decays and extraction of CP violation parameters containing $\phi_3$. Using fully reconstructed $D^{(*)}\pi$ events from a $140 {\rm fb}^{-1}$ data sample collected at the $\Upsilon(4S)$ resonance, we obtain the CP violation parameters for $D^* \pi$ and $D \pi$ decays, $2R_{D^{(*)} \pi} \sin (2\phi_1 + \phi_3 \pm \delta_{D^{(*)} \pi})$, where $R_{D^{(*)} \pi}$ is the ratio of the magnitudes of the doubly-Cabibbo-suppressed and Cabibbo-favoured amplitudes, and $\delta_{D^{(*)} \pi}$ is the strong phase difference between them. Under the assumption of $\delta_{D^{(*)} \pi}$ being close to either 0 or $180^{\circ}$, we obtain $|2R_{D^* \pi} \sin (2\phi_1 + \phi_3)| = 0.060 \pm 0.040(\mathrm{stat}) \pm 0.019(\mathrm{sys})$ and $|2R_{D \pi} \sin (2\phi_1 + \phi_3)| = 0.061 \pm 0.037(\mathrm{stat}) \pm 0.018(\mathrm{sys})$.Comment: 9 pages, 3 figures, Submitted to Physical Review Letter

Search for the b --> d gamma process

We report the results of a search for the flavor-changing neutral current process b --> d gamma using a sample of 275 million B meson pairs accumulated by the Belle detector at KEKB. We find no significant signal for the exclusive decays B- --> rho- gamma, B0B --> rho0 gamma, or B0B --> omega gamma. Assuming an isospin relation between the three modes, we set an upper limit for the combined branching fraction Br(B --> (rho,omega) gamma) < 1.4 x 10-6 at the 90% confidence level. This limit can be used to constrain the ratio of CKM matrix elements |Vtd/Vts|.Comment: 6 pages, 2 figures, submitted to Phys. Rev. D (RC

Observation of the DsJ(2317) and DsJ(2457) in B decays

We report the first observation of the B --> Dbar DsJ(2317) and B --> Dbar DsJ(2457) decays based on 123.8 10^6 BBar events collected with the Belle detector at KEKB. We observe the DsJ(2317) decay to Ds pi0 and DsJ(2457) decay to the Ds* pi0 and Ds gamma final states. We also set 90% CL upper limits for the decays DsJ(2317) --> Ds* gamma, DsJ(2457) --> Ds* gamma, DsJ(2457) --> Ds pi0 and DsJ(2457) --> Ds pi+ pi-.Comment: 6 pages, 3 figures. A few minor corrections. Replaced by version accepted to publication in Phys. Rev. Let

Measurement of the B --> K^* gamma Branching Fractions and Asymmetries

We report measurements of the radiative decay B --> K^*\gamma. The analysis is based on a data sample containing 85.0*10^6 B meson pairs collected by the Belle detector at the KEKB storage ring. We measure branching fractions of Br(B^0 --> K^{*0}\gamma) = (4.01 \pm 0.21 \pm 0.17)*10^{-5} and Br(B^+ --> K^{*+}\gamma) = (4.25 \pm 0.31 \pm 0.24)*10^{-5}, where the first and second errors are statistical and systematic, respectively. The isospin asymmetry between B^0 and B^+ decay widths is measured to be \Delta_{0+} = +0.012 \pm 0.044 \pm 0.026. We search for a partial rate asymmetry between CP conjugate modes, and find A_{cp}(B --> K^*\gamma) = =0.015 \pm 0.044 \pm 0.012.Comment: 10 pages, 5 figures, submitted to Phys. Rev.

Observation of Radiative Decay D0→ϕγD^0 \to \phi \gamma

We report the observation of the decay $D^{0} \to \phi \gamma$ with a statistical significance of $5.4\sigma$ in 78.1 \ifb of data collected by the Belle experiment at the KEKB $e^+ e^-$ collider. This is the first observation of a flavor-changing radiative decay of a charmed meson. The Cabibbo- and color-suppressed decays $D^0 \to \phi \pi^0$, $\phi \eta$ are also observed for the first time. We measure branching fractions \br(D^{0} \to \phi \gamma) = [ 2.60^{+0.70}_{-0.61} \stat {}^{+0.15}_{-0.17} \syst ] \times 10^{-5}, \br(D^{0} \to \phi \pi^{0}) = [ 8.01 \pm 0.26 \stat \pm 0.47 \syst ] \times 10^{-4}, and \br(D^{0} \to \phi \eta) = [ 1.48 \pm 0.47 \stat \pm 0.09 \syst ] \times 10^{-4}.Comment: 9 pages, 4 figures, Belle Preprint 2003-24, KEK Preprint 2003-75, updated version of BELLE-CONF-0346 (contributed paper to the XXI International Symposium on Lepton and Photon Interactions at High Energies,Fermilab Aug 11-16,2003). to appear in Phys. Rev. Let

Study of B0 -> rho+-pi-+ Time-dependent CP Violation at Belle

We present a time-dependent analysis of CP violation in B0 -> rho pi decays based on a 140 1/fb data sample collected at the Y(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e- collider. We fully reconstruct one neutral B meson in the rho+-pi-+ final state and identify the flavor of the accompanying B meson from its decay products. We obtain the charge asymmetry ACP = -0.16+-0.10(stat)+-0.02(syst). An unbinned maximum likelihood fit to the proper-time distributions yields C = 0.25+-0.17(stat)+0.02-0.06(syst), DC = 0.38+-0.18(stat)+0.02-0.04(syst), S = -0.28+-0.23(stat)+0.10-0.08(syst), and DS = -0.30+-0.24(stat)+-0.09(syst). The direct CP violation parameters for B -> rho+pi- and B -> rho-pi+ decays are A+- = -0.02+-0.16(stat)+0.05-0.02(syst) and A-+ = -0.53+-0.29(stat)+0.09-0.04(syst).Comment: 10 pages, 3 figures, submitted to Phys. Rev. Let

Determination of |V_ub| from Measurements of the Inclusive Charmless Semileptonic Partial Rates of B Mesons using Full Reconstruction Tags

We present a measurement of the Cabibbo-Kobayashi-Maskawa matrix element |V_ub|, based on 253 fb^-1 of data collected by the Belle detector at the KEKB e^+e^- asymmetric collider. Events are tagged by fully reconstructing one of the B mesons, produced in pairs from Upsilon(4S). The signal for b->u semileptonic decay is distinguished from the b->c background using the hadronic mass M_X, the leptonic invariant mass squared q^2 and the variable P_+ = E_X-|\vec{p}_X|. The results are obtained for events with the prompt-lepton momentum, p_l^* >= 1GeV/c, in three kinematic regions (1) M_X < 1.7 Gev/c^2, (2) M_X 8 GeV^2/c^2, and by (3) P_+ < 0.66 GeV/c, allowing for a comparison of the three methods. The matrix element |V_ub| is found to be (4.09+-0.19+-0.20(+0.14-0.15)+-0.18), where the errors are statistical, systematic including Monte Carlo modeling, theoretical, and from shape function parameter determination, respectively.Comment: 6 pages, 3 figures, 3 tables. Version as it appears in PRL. Changes from v1: |V_ub| recalculated using mb(SF)=4.60+-0.04 and mu_pi^2(SF)=0.20+-0.04. Title and text changed to reflect the calculation of partial rate instead of partial Br. Fig. 3 changed. Explicit dependence of the result on mb(SF) is give