58 research outputs found
CP Violating B ---> s Gamma Decay in Supersymmetric Models
Supersymmetric models with nonuniversal down type squark masses can enrich
the chiral structure and CP violating phenomena in decays.
Direct CP violation in , mixing induced CP violation in
radiative decays (such as and ), and polarization in
can be substantially different from the Standard Model. Future experiements at
and hadronic B factories will give important information on the
underlying theory for radiative decays.Comment: 19 pages, 8 figures, Latex. To appear in Phys. Rev.
25th-order high-temperature expansion results for three-dimensional Ising-like systems on the simple cubic lattice
25th-order high-temperature series are computed for a general
nearest-neighbor three-dimensional Ising model with arbitrary potential on the
simple cubic lattice. In particular, we consider three improved potentials
characterized by suppressed leading scaling corrections. Critical exponents are
extracted from high-temperature series specialized to improved potentials,
obtaining , , ,
, , . Moreover, biased
analyses of the 25th-order series of the standard Ising model provide the
estimate for the exponent associated with the leading scaling
corrections. By the same technique, we study the small-magnetization expansion
of the Helmholtz free energy. The results are then applied to the construction
of parametric representations of the critical equation of state, using a
systematic approach based on a global stationarity condition. Accurate
estimates of several universal amplitude ratios are also presented.Comment: 40 pages, 15 figure
Search for Lepton-Flavor-Violating tau Decays into a Lepton and an f0(980) Meson
We search for lepton-flavor-violating tau decays into a lepton (electron or
muon) and an f0(980) meson using 671 fb-1 of data collected with the Belle
detector at the KEKB asymmetric-energy e+e- collider. No events are observed
and we set the following 90% C.L. upper limits on the branching fraction
products: B(tau- -> e-f0(980))*B(f0(980)->pi+pi-)
mu-f0(980))*B(f0(980) -> pi+pi-)<3.4x10^-8. This is the first search performed
for these modes.Comment: 10 pages, 4 figures, submitted to Phys. Lett.
Search for neutrinoless decays tau -> 3l
We have searched for neutrinoless tau lepton decays into three charged
leptons using an 87.1 fb^{-1} data sample collected with the Belle detector at
the KEKB e^+e^- collider. Since the number of signal candidate events is
compatible with that expected from the background, we set 90% confidence level
upper limits on the branching fractions in the range (1.9-3.5) x 10^{-7} for
various decay modes tau -> l l l where l represents e or mu.Comment: 12 pages, 4figure
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
Search for lepton flavor violating decays tau- -> l- pi0, l- eta, l- eta'
We have searched for lepton flavor violating semileptonic tau decays using a
data sample of 153.8/fb accumulated with the Belle detector at the KEKB e+e-
collider. For the six decay modes studied, the observed yield is compatible
with the estimated background and the following upper limits are set at the 90%
confidence level: B(tau- -> e- eta) mu- eta) < 1.5 x
10^-7, B(tau- -> e- pi0) mu- pi0) < 4.1 x 10^-7,
B(tau- -> e- eta') mu- eta') < 4.7 x 10^-7. These
results are 10 to 64 times more restrictive than previous limits.Comment: 14 pages, 13 figures, RevTex
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