alpha-particle production in the scattering of 6He by 208Pb at energies around the Coulomb barrier

New experimental data from the scattering of 6He+208Pb at energies around and below the Coulomb barrier are presented. The yield of breakup products coming from projectile fragmentation is dominated by a strong group of $\alpha$ particles. The energy and angular distributions of this group have been analyzed and compared with theoretical calculations. This analysis indicates that the $\alpha$ particles emitted at backward angles in this reaction are mainly due to two-neutron transfer to weakly bound states of the final nucleus.Comment: 20 pages, 5 figures. Nuclear Physics A792 (2007) 2-1

Astroparticle Physics with a Customized Low-Background Broad Energy Germanium Detector

The MAJORANA Collaboration is building the MAJORANA DEMONSTRATOR, a 60 kg array of high purity germanium detectors housed in an ultra-low background shield at the Sanford Underground Laboratory in Lead, SD. The MAJORANA DEMONSTRATOR will search for neutrinoless double-beta decay of 76Ge while demonstrating the feasibility of a tonne-scale experiment. It may also carry out a dark matter search in the 1-10 GeV/c^2 mass range. We have found that customized Broad Energy Germanium (BEGe) detectors produced by Canberra have several desirable features for a neutrinoless double-beta decay experiment, including low electronic noise, excellent pulse shape analysis capabilities, and simple fabrication. We have deployed a customized BEGe, the MAJORANA Low-Background BEGe at Kimballton (MALBEK), in a low-background cryostat and shield at the Kimballton Underground Research Facility in Virginia. This paper will focus on the detector characteristics and measurements that can be performed with such a radiation detector in a low-background environment.Comment: Submitted to NIMA Proceedings, SORMA XII. 9 pages, 4 figure

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.

Search for Lepton-Flavor-Violating and Lepton-Number-Violating tau to lhh' Decay Modes

We search for lepton-flavor-violating and lepton-number-violating tau decays into a lepton (l = electron or muon) and two charged mesons (h, h' = pion or Kaon) using 854 fb^{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e^+e^- collider. We obtain 90% confidence level upper limits on the tau to lhh' branching fractions in the range (2.0-8.4)*10^{-8}. These results improve upon our previously published upper limits by factors of about 1.8 on average.Comment: 14 pages, 5 figures, submitted to Phys. Lett.

Measurement of the Branching Fractions for B→ωKB \to \omega K and B→ωπB \to \omega \pi

We report improved measurements of branching fractions for charmless hadronic two-body {\it B} meson decays containing an $\omega$ meson in the final state. The results are based on a data sample of 78 fb$^{-1}$ collected on the $\Upsilon(4S)$ resonance by the Belle detector. We measure the branching fractions ${\mathcal B}(B^+ \to \omega K^+) = (6.5^{+1.3}_{-1.2}\pm 0.6)\times 10^{-6}$ and ${\mathcal B}(B^+ \to \omega \pi^+) = (5.7^{+1.4}_{-1.3}\pm 0.6)\times 10^{-6}.$ We give 90% confidence upper limits for ${\mathcal B}(B^0 \to \omega K^0) < 7.6\times 10^{-6}$ and ${\mathcal B}(B^0 \to \omega \pi^0) < 1.9\times 10^{-6}.$ We also obtain the partial rate asymmetries ${\mathcal A}_{CP}=0.06^{+0.21}_{-0.18}\pm 0.01$ for $B^\pm \to \omega K^\pm$ and ${\mathcal A}_{CP}=0.50^{+0.23}_{-0.20}\pm 0.02$ for $B^\pm \to \omega \pi^\pm.$Comment: 7 pages, 4 figures, tar.gz files submitted to PR

Measurement of D0-D0 mixing and search for CP violation in D0→K+K-,π+π- decays with the full Belle data set

We report an improved measurement of D0 – D‾0 mixing and a search for CP violation in D0 decays to CP -even final states K+K− and π+π− . The measurement is based on the final Belle data sample of 976 fb −1 . The results are yCP=(1.11±0.22±0.09)% and AΓ=(−0.03±0.20±0.07)% , where the first uncertainty is statistical and the second is systematic

Study of the Hadronic Decays of \chi_c States

Hadronic decays of the P-wave spin-triplet charmonium states \chi_cJ (J=0,1,2) are studied using a sample of \psi(2S) decays collected by the BES detector operating at the BEPC storage ring. Branching fractions for the decays \chi_c1 going to K_s^0 K^+ \pi^- + c.c., \chi_c0 going to K_s^0 K_s^0, \chi_c2 going to K_s^0 K_s^0, \chi_c0 going to \phi \phi, \chi_c2 going to \phi \phi and \chi_cJ going to K^+ K^- K^+ K^- are measured for the first time, and those for \chi_cJ going to \pi^+ \pi^- \pi^+ \pi^-, $ \chi_cJ going to \pi^+ \pi^- K^+ K^-, \chi_cJ going to \pi^+ \pi^- p \bar{p} and \chi_cJ going to 3(\pi^+ \pi^-) are measured with improved precision. In addition, we determine the masses of the \chi_c0 and \eta_c to be M_{\chi_{c0}}=3414.1 \pm 0.6(stat) \pm 0.8 (sys) MeV and M_{\eta_c}=2975.8 \pm 3.9(stat) \pm 1.2 (sys) MeV.Comment: 24 pages, 12 figures, 6 tables, use revtex, submitted to Phys. Rev.

Partial Wave Analyses of J/ψ→γK+K−J/\psi\to\gamma K^+K^- and γKS0KS0\gamma K^0_SK^0_S

Results are presented on $J/\psi$ radiative decays to $K^+K^-$ and $K^0_SK^0_S$ based on a sample of 58M $J/\psi$ events taken with the BES II detector. A partial wave analysis is carried out using the relativistic covariant tensor amplitude method in the 1-2 GeV mass range. There is conspicuous production due to the $f'_2(1525)$ and $f_0(1710)$. The latter peaks at a mass of $1740\pm 4^{+10}_{-25}$ MeV with a width of $166{^{+5}_{-8}}{^{+15}_{-10}}$ MeV. Spin 0 is strongly preferred over spin 2. For the $f'_2(1525)$, the helicity amplitude ratios are determined to be $x^2 = 1.00\pm0.28^{+1.06}_{-0.36}$ and $y^2 = 0.44\pm{0.08}^{+0.10}_{-0.56}$.Comment: 16 pages, 5 figure