3,595 research outputs found
Getting beta-alpha without penguins
Oscillation effects in B0 -> Ks D0 and related processes are considered to
determine delta=beta-alpha+pi. We suggest that D0 decays to CP eigenstates used
in concert with inclusive D0 decays provide a powerful method for determining
delta cleanly i.e. without any complication from penguin processes. The CP
asymmetry is expected to be <=40% for D0 decays to non-CP eigenstates and <=80%
for decays to CP eigenstates. This method can lead to a fairly accurate
determination of delta with O(10^8-10^9) B-mesons.Comment: 4 pages 1 figure; Version 2: minor changes; references added; Some
changes in response to Referee Comment
Desperately Seeking Non-Standard Phases via Direct CP Violation in Process
Attributing the recent CLEO discovery of to originate
(primarily) from the fragmentation of an off-shell gluon () via , , we emphasize that many such states () should
materialize. Indeed the hadronic fragments () of states are closely
related to those seen in . A particular
final state of considerable interest is . Signals from such states
in decays can be combined to provide a very sensitive search for CP
violating phase(s) from non-standard physics. The method should work even if
the contribution of these source(s) to the rates is rather small () to
the point that a comparison between theory and experiment may find it extremely
difficult to reveal the presence of such a new physics.Comment: 16 pages, 5 figure
Genetics Analysis Workshop 16 Problem 2: tTe Framingham Heart Study Data
Genetic Analysis Workshop 16 (GAW16) Problem 2 presented data from the Framingham Heart Study (FHS), an observational, prospective study of risk factors for cardiovascular disease begun in 1948. Data have been collected in three generations of family participants in the study and the data presented for GAW16 included phenotype data from all three generations, with four examinations of data collected repeatedly for the first two generations. The trait data consisted of information on blood pressure, hypertension treatment, lipid levels, diabetes and blood glucose, smoking, alcohol consumed, weight, and coronary heart disease incidence. Additionally, genotype data obtained through a genome-wide scan (FHS SHARe) of 550,000 single-nucleotide polymorphisms from Affymetrix chips were included with the GAW16 data. The genotype data were also used for GAW16 Problem 3, where simulated phenotypes were generated using the actual FHS genotypes. These data served to provide investigators with a rich resource to study the behavior of genome-wide scans with longitudinally collected family data and to develop and apply new procedures.National Heart, Lung and Blood Institute (2 N01-HC-25195-06); National Institutes of Health (National Institute of General Medical Sciences R01 GM031575
The Anomalous Magnetic Moment of the Muon and Higgs-Mediated Flavor Changing Neutral Currents
In the two-Higgs doublet extension of the standard model, flavor-changing
neutral couplings arise naturally. In the lepton sector, the largest such
coupling is expected to be $\mu-\tau-\phi#. We consider the effects of this
coupling on the anomalous magnetic moment of the muon. The resulting bound on
the coupling, unlike previous bounds, is independent of the value of other
unknown couplings. It will be significantly improved by the upcoming E821
experiment at Brookhaven National Lab.Comment: 7 pages Latex, 2 figure
Structure and composition of commercial copper chelate extractants
Journal ArticleThe structure, properties, and composition of commercial chelating-type copper extractants are examined. Characterization of these extractants was accomplished using organic separation techniques and analytical tools such as NMR and infrared spectroscopy. Results indicate that only the trans isomer of the diphenylhydroxyoxime (LIXÂź64N) is capable of copper chelation. The effects of structural modification of the extractants on the extraction and stripping reactions are discussed
Texture of Yukawa coupling matrices in general two-Higgs-doublet model
We discuss possible parallel textures of the Yukawa coupling matrices in the
generaltwo-Higgs-doublet model (2HDM). In those textures the flavor changing
neutral currentsare naturally suppressed. Motivated by a phenomenologically
successful texturewith four texture zeros in the standard model, we propose a
predictive ansatz for the Yukawa coupling matrices with the same texture in the
general 2HDM. Compared with the six texture-zero based ansatz proposed by Cheng
and Sher, it is in a better agreement with the data of quark mixings and CP
violation. The four texture-zero based ansatz predicts a different hierarchy in
the Yukawa coupling matrix elements. As a consequence, in the lepton sector,
the related Yukawa couplings are less constrained by the experimental upper
bound of , which allows significantly larger predictions for
other processes. The contributions from neutral scalar interactions to the
lepton number violation decay modes are
calculated in both ansatz. It is shown that the predictions from the four
texture-zero based ansatz could be two order of magnitude greater than that
from the six texture-zero based one. The branching ratio of and
can reach and 1.3\tiems 10^{-10}
respectively. The predicted ratio of is also
larger and almost parameter independent. Those differences make the two ansatz
to be easily distinguished by the future experiments.Comment: 12 pages, 2 figure
b --> s g g decay in the two and three Higgs doublet models with CP violating effects
We study the decay width and CP-asymmetry of the inclusive process b--> s g g
(g denotes gluon) in the three and two Higgs doublet models with complex Yukawa
couplings. We analyse the dependencies of the differential decay width and
CP-asymmetry to the s- quark energy E_s and CP violating parameter \theta. We
observe that there exist a considerable enhancement in the decay width and CP
asymmetry is at the order of 10^{-2}. Further, it is possible to predict the
sign of C_7^{eff} using the CP asymmetry.Comment: 15 pages, 7 Figures (required epsf style
Lepton Flavor Violation in the Two Higgs Doublet Model type III
We consider the Two Higgs Doublet Model (2HDM) of type III which leads to
Flavour Changing Neutral Currents (FCNC) at tree level in the leptonic sector.
In the framework of this model we can have, in principle, two situations: the
case (a) when both doublets acquire a vacuum expectation value different from
zero and the case (b) when only one of them is not zero. In addition, we show
that we can make two types of rotations for the flavor mixing matrices which
generates four types of lagrangians, with the rotation of type I we recover the
case (b) from the case (a) in the limit , and with the
rotation of type II we obtain the case (b) from (a) in the limit Moreover, two of the four possible lagrangians correspond to the models
of types I and II plus Flavor Changing (FC) interactions. The analitical
expressions of the partial lepton number violating widths and are derived for the cases (a) and (b) and both
types of rotations.In all cases these widths go asymptotically to zero in
the decoupling limit for all Higgses. We present from our analysis upper bounds
for the flavour changing transition and we show that such bounds
are sensitive to the VEV structure and the type of rotation utilized.Comment: 7 pages RevTeX4, 4 figures postscript, new section added and some new
reference
Time dependent CP asymmetry in decay to probe the origin of CP violation
Since the CP violation in the system has been investigated up to now only
through processes related to the -- mixing, urgently required is
new way of study for the CP violation and establishing its origin in the
system independent of the mixing process. In this work, we explore the
exclusive decay to obtain the time-dependent CP
asymmetry in decay process in the standard model and the
supersymmetric model. We find that the complex RL and RR mass insertion to the
squark sector in the MSSM can lead to a large CP asymmetry in
decay through the gluino-squark diagrams, which is not predicted in the
Standard Model induced by the -- mixing.Comment: 10 pages, 4 eps figure
Determining the top-antitop and Couplings of a Neutral Higgs Boson of Arbitrary CP Nature at the NLC
The optimal procedure for extracting the coefficients of different components
of a cross section which takes the form of unknown coefficients times functions
of known kinematical form is developed. When applied to \epem\to t\anti
t+Higgs production at \rts=1\tev and integrated luminosity of 200\fbi, we
find that the t\anti t\toHiggs CP-even and CP-odd couplings and, to a lesser
extent, the Higgs (CP-even) coupling can be extracted with reasonable
errors, assuming the Higgs sector parameter choices yield a significant
production rate. Indeed, the composition of a mixed-CP Higgs eigenstate can be
determined with sufficient accuracy that a SM-like CP-even Higgs boson can be
distinguished from a purely CP-odd Higgs boson at a high level of statistical
significance, and vice versa.Comment: 8 pages, full postscript file also available via anonymous ftp at
ftp://ucdhep.ucdavis.edu/gunion/eetottbh.p
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