7,363 research outputs found
Penguins and Mixing Dependent CP Violation
Constraints on angles of Unitarity triangle are reviewed, and in particular
constraint on from limit on is emphasized. Effects of
penguin diagram on measurement of and are then reviewed. New
measurements on in QCD improved factorization approximation
suggest large penguin effects. It is possible to estimate the error in
measurement of as a function of for different values.Comment: LaTeX, 11 pages, 3 eps figures, Talk presented at the Third
International Conference on B Physics and CP Violation, Taipei, December 3-7,
199
CP Violating Rate Difference Relations for and in Broken SU(3)
Within the standard model there exist certain relations between CP violating
rate differences in B decays in the SU(3) limit. We study SU(3) breaking
corrections to these relations in the case of charmless, hadronic, two body
decays using the improved factorization model of Ref.\cite{3}. We consider the
cases and for both and mesons. We present an
estimate for in terms of .Comment: Latex 13 pages, no figure
Leptoquark explanation of HERA anomaly in the context of gauge unification
We examine the consequences of leptoquark explanation of HERA anomaly in the
context of R parity conserving supersymmetric gauge unified theory with the
gauge unification scale at GeV. We pointed out the difficulty of
constructing a grandunified theory. However gauge unification is still possible
at GeV when additional multiplets are introduced. We determine
the mass spectrum of these additional fields (fermions and scalars) in gauge
mediated and supergravity scenarios. Unique signatures and mass bounds are
discussed.Comment: 19 pages(Latex), 1 PS Figur
Overview of escalator applications in rail transit
The difference in operating environment and in construction between escalators in transit and nontransit use, the impact of recent escalator innovations, and areas which could benefit from urban mass transportation administration sponsored research and development are determined. Several factors causing a more severe transit escalator operating environment are identified. There are no significant design differences between transit and nontransit escalators. Recent innovations that have affected performance and cost include outdoor escalators, extra flat steps at both landings, and modular escalators. Data were collected by interviews at transit agencies. Long term, unscheduled, escalator maintenance records were available for analysis from one property. A description of escalator operating principles is provided. Transit represents less than 5% of the U.S. escalator market. Transit agencies have limited leverage on escalator industry practices. A substantial impact on transit escalator cost and performance can be achieved by research identifying when and how to apply and specify several of the more recent innovations. Purchase of escalators under long term (25 year) maintenance contracts is one method that has been used to promote escalators manufactured for minimum life cycle cost
Consequences of R-Parity violating interactions for anomalies in and
We investigate the possibility of explaining the enhancement in semileptonic
decays of , the anomalies induced by in and violation of lepton
universality in
within the framework of R-parity violating (RPV) MSSM. Exchange of down type
right-handed squark coupled to quarks and leptons yield interactions which are
similar to leptoquark induced interactions that have been proposed to explain
the by tree level interactions and anomalies by loop induced interactions, simultaneously. However,
the Yukawa couplings in such theories have severe constraints from other rare
processes in and decays. Although this interaction can provide a viable
solution to anomaly, we show that with the severe constraint from
, it is impossible to solve the anomalies in process simultaneously.Comment: RevTex, 13 pages, three figures. In our earlier version, we had
neglected a contribution to C^{NP}_9 and obtained erroneous conclusions which
we have corrected them in this versio
Evaluation of ADAM/1 model for advanced coal extraction concepts
Several existing computer programs for estimating life cycle cost of mining systems were evaluated. A commercially available program, ADAM/1 was found to be satisfactory in relation to the needs of the advanced coal extraction project. Two test cases were run to confirm the ability of the program to handle nonconventional mining equipment and procedures. The results were satisfactory. The model, therefore, is recommended to the project team for evaluation of their conceptual designs
Triple Neutral Gauge Boson Couplings in Noncommutative Standard Model
It has been shown recently that the triple neutral gauge boson couplings are
not uniquely determined in noncommutative extension of the Standard Model
(NCSM). Depending on specific schemes used, the couplings are different and may
even be zero. To distinguish different realizations of the NCSM, additional
information either from theoretical or experimental considerations is needed.
In this paper we show that these couplings can be uniquely determined from
considerations of unification of electroweak and strong interactions. Using
SU(5) as the underlying theory and integrating out the heavy degrees of
freedom, we obtain unique non-zero new triple , , , , , and couplings at the
leading order in the NCSM. We also briefly discuss experimental implications.Comment: 8 pages, Latex, no figur
M\"{o}ller and Bhabha scattering in the noncommutative standard model
We study the M\"{o}ller and Bhabha scattering in the noncommutative extension
of the standard model(SM) using the Seiberg-Witten maps of this to first order
of the noncommutative parameter . We look at the angular
distribution to explore the noncommutativity of space-time at
around TeV and find that the distribution deviates
significantly from the one obtained from the commutative version of the
standard model.Comment: 15 pages, 14 eps figures.Text is modified a little and version to
appear in Phys.Rev.
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