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 Physics , 2015, DOI: 10.1103/PhysRevD.91.071101 Abstract: We report a search for the rare charmless decay $B^+\rightarrow\overline{K}{}^{*0}K^{*+}$ using a data sample of $772\times10^6$ $B\bar{B}$ pairs collected at the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. No statistically significant signal is found and a 90% confidence-level upper limit is set on the decay branching fraction as $\mathcal{B}(B^+\rightarrow\overline{K}{}^{*0}K^{*+}) <1.31\times 10^{-6}$.
 KamLAND Collaboration Physics , 2015, DOI: 10.1103/PhysRevD.92.052006 Abstract: We present a search for the proton decay mode $p \rightarrow \overline{\nu} K^{+}$ based on an exposure of 8.97 kton-years in the KamLAND experiment. The liquid scintillator detector is sensitive to successive signals from $p \rightarrow \overline{\nu} K^{+}$ with unique kinematics, which allow us to achieve a detection efficiency of 44%, higher than previous searches in water Cherenkov detectors. We find no evidence of proton decays for this mode. The expected background, which is dominated by atmospheric neutrinos, is $0.9 \pm 0.2$ events. The nonbackground-subtracted limit on the partial proton lifetime is $\tau / B(p \rightarrow \overline{\nu} K^{+}) > 5.4 \times 10^{32}$ years at 90% C.L.
 Physics , 1993, Abstract: Preliminary results are presented on the calculation of the relevant form factor for the radiative decay $\overline{B} \rightarrow K^* \gamma$ We find that the form factor is weakly dependent on the spectator quark mass. We compare the results obtained for a full chiral extrapolation and where this independence is assumed. Both results are found to be statistically consistent with the experimental data.
 Physics , 2015, Abstract: We measure the decay $B_s^0\rightarrow K^0\overline{K}^0$ using data collected at the $\Upsilon(5S)$ resonance with the Belle detector at the KEKB $e^+e^-$ collider. The data sample used corresponds to an integrated luminosity of 121.4 ${\rm fb^{-1}}$. We measure a branching fraction $\mathcal{B}(B_s^0\rightarrow K^0\overline{K}^0) = [19.6\,^{+5.8}_{-5.1}({\rm stat.})\,\pm1.0({\rm sys.})\,\pm 2.0(N^{}_{B_s^0\overline{B}_s^0})]\times 10^{-6}$ with a significance of 5.1 standard deviations. This measurement constitutes the first observation of this decay.
 The BABAR Collaboration Physics , 2013, DOI: 10.1103/PhysRevD.89.071102 Abstract: We report a search for the decay ${\overline B}^{0}\rightarrow{\Lambda_{\rm c}^{+}}{\overline p}{p}{\overline p}$. Using a data sample of $471 \times 10^6\: B{\overline B}$ pairs collected with the BABAR detector at the PEP-II storage ring at SLAC, we find no events and set an upper limit on the branching fraction ${\cal B}({\overline B}^{0}\rightarrow{\Lambda_{\rm c}^{+}}{\overline p}{p}{\overline p}) \times\frac{{\cal B}(\Lambda_{\rm c}^{+}\rightarrow p K^{-} \pi^{+})}{0.050} < 2.8\times10^{-6}$ at $90\,%$ C.L., where we have normalized ${\cal B}(\Lambda_{\rm c}^{+}\rightarrow p K^{-} \pi^{+})$ to the world average value.
 Physics , 2013, DOI: 10.1016/j.physletb.2013.12.039 Abstract: A search for $K^-pp$ bound state (the lightest kaonic nucleus) has been performed using the $\gamma d \rightarrow K^+ \pi^- \rm{X}$ reaction at E$_\gamma$=1.5-2.4 GeV at LEPS/SPring-8. The differential cross section of $K^+ \pi^-$ photo-production off deuterium has been measured for the first time in this energy region, and a bump structure was searched for in the inclusive missing mass spectrum. A statistically significant bump structure was not observed in the region from 2.22 to 2.36 GeV/$c^2$, and the upper limits of the differential cross section for the $K^-pp$ bound state production were determined to be 0.1$-$0.7 $\mu$ b (95$%$ confidence level) for a set of assumed binding energy and width values.
 Physics , 1995, DOI: 10.1103/PhysRevLett.76.1421 Abstract: An upper limit on the branching ratio for the decay $K^+ \! \rightarrow \! \pi^+ \nu \overline{\nu}$ is set at $2.4 \times 10^{-9}$ at the 90\% C.L. using pions in the kinematic region $214~{\rm MeV}/c < P_\pi < 231~{\rm MeV}/c$. An upper limit of $5.2 \times 10^{-10}$ is found on the branching ratio for decays $K^+ \! \rightarrow \! \pi^+ X^0$, where $X^0$ is any massless, weakly interacting neutral particle. Limits are also set for cases where $M_{X^0}>0$.
 Physics , 1995, DOI: 10.1016/0370-2693(96)00845-3 Abstract: We study the reactions $K \rightarrow \pi \pi \nu \overline{\nu}$ within the minimal standard model. We use isospin symmetry to relate the matrix elements to the form factors measured in $K_{\ell 4}$. We argue that these modes are short distance dominated and can be used for precise determinations of the CKM parameters $\rho$ and $\eta$. Depending on the value of the CKM angles we find branching ratios in the following ranges: $B(K_L \rightarrow \pi^+ \pi^- \nu \overline{\nu}) = [2-5] \times 10^{-13}$; $B(K_L \rightarrow \pi^0 \pi^0 \nu \overline{\nu}) = [1-3] \times 10^{-13}$; $B(K^+ \rightarrow \pi^+ \pi^0 \nu \overline{\nu}) = [1-2] \times 10^{-14}$. We also discuss a possible $CP$-odd observable.
 Physics , 2015, Abstract: We report on a study of the exchange tunneling reaction D+HD$\rightarrow$D$_{2}$+H in solid HD at temperatures between 130~mK and 1.5~K by electron spin resonance. The reaction proceeds at almost the same rate ($\sim3\times10^{-27}$cm$^{3}$s$^{-1}$) within this temperature range. This observation differs strongly with the recombination rate of H atoms in solid H$_{2}$ which was found substantially reduced upon lowering temperature below 1$\,$K. These results suggest that the tunneling exchange reaction $\textrm{H}+\textrm{H}_{2}\rightarrow\textrm{H}_{2}+\textrm{H}$ can take place in solid H$_{2}$ even though recombination is suppressed at ultra low temperatures in pure hydrogen.
 Physics , 1996, Abstract: A simple partial wave amplitude analysis of $\overline{p}p \rightarrow K^-K^+$ has been performed for data in the range $p_{\rm lab}$ = 360 -- 1000 MeV/$c$. In this low momentum interval only partial wave amplitudes with $J$ equal to 0, 1 and 2 are needed to obtain a good fit to the experimental data. This maximal $J$ = 2 value is smaller than what is required for the data of the reaction $\overline{p}p \rightarrow \pi^-\pi^+$ in the same momentum interval.
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