116536256
Two-body B meson decays to eta and eta-prime Observation of B ---> eta-prime K
181671081
Search for B ---> K lepton+ lepton- and B ---> K* lepton+ lepton- decays
34604877
Measurement of Cabibbo-suppressed decays of the tau lepton.
Branching ratios for the dominant Cabibbo-suppressed decays of the [tau] lepton have been measured by CLEO II in [ital e][sup +][ital e][sup [minus]] annihilation at the Cornell Electron Storage Ring ([radical][ital s] [similar to]10.6 GeV) using kaons with momenta below 0.7 GeV/[ital c]. The inclusive branching ratio into one charged kaon is (1.60[plus minus]0.12[plus minus]0.19)%. For the exclusive decays, [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]][nu][sub [tau]])=(0.66[plus minus]0.07[plus minus]0.09)%, [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]][pi][sup 0][nu][sub [tau]])=(0.51 [plus minus]0.10[plus minus]0.07)%, and, based on three events, [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]]2[pi][sup 0][nu][sub [tau]])[lt]0.3% at the 90% confidence level. These represent significant improvements over previous results. [ital B]([tau][sup [minus]][r arrow][ital K][sup [minus]][pi][sup 0][nu][sub [tau]]) is measured for the first time with exclusive [pi][sup 0] reconstruction.
117035924
Measurement of B (tau- ---> tau-neutrino K- K0) and b (tau- ---> tau-neutrino K- K0 pi0)
12584275
Study of charmless hadronic B meson decays to pseudoscalar-vector final states.
We report results of searches for charmless hadronic B meson decays to pseudoscalar( pi(+/-), K+/-, pi(0), or K(0)(S))-vector( rho, K(*), or omega) final states. By using 9.7x10(6) BB pairs collected with the CLEO detector, we report the first observation of B(-)--->pi(-)rho(0), B(0)-->pi(+/-)rho(-/+), and B(-)-->pi(-)omega, which are expected to be dominated by hadronic b-->u transitions. The measured branching fractions are (10.4(+3.3)(-3.4)+/-2.1)x10(-6), (27.6(+8.4)(-7.4)+/-4.2)x10(-6), and (11.3(+3.3)(-2.9)+/-1. 4)x10(-6), respectively. Branching fraction upper limits are set for all of the other decay modes investigated.
16089528
Observation of radiative leptonic decay of the tau lepton
Using 4.68 fb(-1) of e(+)e(-) annihilation data collected with the CLEO II detector at the Cornell Electron Storage Ring, we have studied tau radiative decays tau(-)-->nu(tau)&mgr;(-)nu;(&mgr;)gamma and tau(-)-->nu(tau)e(-)nu;(e)gamma. For a 10 MeV minimum photon energy in the tau rest frame, the branching fraction for radiative tau decay to a muon or electron is measured to be (3.61+/-0.16+/-0. 35)x10(-3) or (1.75+/-0.06+/-0.17)x10(-2), respectively. The branching fractions are in agreement with standard model theoretical predictions.
118396807
Study of exclusive charmless semileptonic decays of the B meson
5767438
Detection of Pulsed Gamma Rays Above 100 GeV from the Crab Pulsar
This detection constrains the mechanism and emission region of gamma-ray radiation in the pulsar’s magnetosphere. We report the detection of pulsed gamma rays from the Crab pulsar at energies above 100 giga–electron volts (GeV) with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) array of atmospheric Cherenkov telescopes. The detection cannot be explained on the basis of current pulsar models. The photon spectrum of pulsed emission between 100 mega–electron volts and 400 GeV is described by a broken power law that is statistically preferred over a power law with an exponential cutoff. It is unlikely that the observation can be explained by invoking curvature radiation as the origin of the observed gamma rays above 100 GeV. Our findings require that these gamma rays be produced more than 10 stellar radii from the neutron star.
120014189
Fat bundles and symplectic manifolds
A fat bundle is, roughly speaking, a bundle which has a lot of curvature, as opposed to a flat bundle, which has none. (The precise definition is given in Section 1.) For example, a bundle with structure group S’ is fat if it has a connection whose curvature is a symplectic structure on the base. The notion of fat bundle arises naturally from the study of riemannian fibre bundles with totally geodesic fibres. Positivity of certain sectional curvatures turns out to be equivalent to fatness of the connection determined by the orthogonal complements to the fibres. It was for this reason that fat bundles were introduced in a manuscript written at MIT in 1968 and circulated informally [20]. (The term unj7at used in that manuscript to mean fat is rather lacking in euphony; it is also slightly misleading, since a bundle which is not flat might not be unflat either-most bundles are somewhere in between.) Some of the results in this paper are taken from the 1968 manuscript, in particular Lemma 3.1, Theorem 4.1 and its corollaries, Theorem 6.1, and Theorem 7.2, but there are substantial additions as well. Using an idea of Sternberg, we show in Section 3 how to construct symplectic manifolds out of any fat bundle, using coadjoint orbits of the structure group; we then continue the discussion by using an idea of Thurston [ 181 to show that, whatever the connection, it is often possible to put a symplectic structure on the total space of a bundle whose tibres and base are symplectic. (In particular, it is sufficient that the bundle be compact and have simply connected fibres.) A problem which was posed and partially solved in [20] was to determine the fat 3-sphere bundles over S4. This problem has just been solved by Derdziriski and Rigas [7]-there is only the Hopf tibration S3 + S’ + S4. Their solution (see Section 7) uses ideas generated by the recent revival of interest in 4-dimensional riemarmian geometry [2] centered around the notion of self-duality. Several important contributions to the theory of fat bundles have been
42542272
A Search for Dark Matter Annihilation with the Whipple 10 m Telescope
We present observations of the dwarf galaxies Draco and Ursa Minor, the Local Group galaxies M32 and M33, and the globular cluster M15 conducted with the Whipple 10 m gamma-ray telescope to search for the gamma-ray signature of self-annihilating weakly interacting massive particles (WIMPs), which may constitute astrophysical dark matter (DM). We review the motivations for selecting these sources based on their unique astrophysical environments and report the results of the data analysis that produced upper limits on the excess rate of gamma rays for each source. We consider models for the DM distribution in each source based on the available observational constraints and discuss possible scenarios for the enhancement of the gamma-ray luminosity. Limits on the thermally averaged product of the total self-annihilation cross section and velocity of the WIMP, -->?? , are derived using conservative estimates for the magnitude of the astrophysical contribution to the gamma-ray flux. Although these limits do not constrain predictions from the currently favored theoretical models of supersymmetry (SUSY), future observations with VERITAS will probe a larger region of the WIMP parameter phase space, -->?? , and WIMP particle mass ( -->m?).
115175355
GROUPOID SYMMETRY AND CONSTRAINTS IN GENERAL RELATIVITY
When the vacuum Einstein equations are cast in the form of Hamiltonian evolution equations, the initial data lie in the cotangent bundle of the manifold of Riemannian metrics on a Cauchy hypersurface Σ. As in every Lagrangian field theory with symmetries, the initial data must satisfy constraints. But, unlike those of gauge theories, the constraints of general relativity do not arise as momenta of any Hamiltonian group action. In this paper, we show that the bracket relations among the constraints of general relativity are identical to the bracket relations in the Lie algebroid of a groupoid consisting of diffeomorphisms between space-like hypersurfaces in spacetimes. A direct connection is still missing between the constraints themselves, whose definition is closely related to the Einstein equations, and our groupoid, in which the Einstein equations play no role at all. We discuss some of the difficulties involved in making such a connection. In an appendix, we develop some aspects of diffeology, the basic framework for our treatment of function spaces.