2,859 research outputs found
A theorem on maximal monotonic sets in Hilbert space
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32073/1/0000117.pd
Prospects for Direct CP Violaton in Exclusive and Inclusive Charmless B decays
Within the Standard Model, CP rate asymmetries for could
reach 10%. With strong final state phases, they could go up to 20--30%, even
for mode which would have opposite sign. We can account for
, and rate data with new physics enhanced
color dipole coupling and destructive interference. Asymmetries could reach
40--60% for and modes and are all of the same sign. We are
unable to account for rate. Our inclusive study supports our
exclusive results.Comment: Minor changes, correct a small bug in Fig. 1(b). Version to appear in
Phys. Rev. Let
Solving the SUSY CP problem with flavor breaking F-terms
Supersymmetric flavor models for the radiative generation of fermion masses
offer an alternative way to solve the SUSY-CP problem. We assume that the
supersymmetric theory is flavor and CP conserving. CP violating phases are
associated to the vacuum expectation values of flavor violating susy-breaking
fields. As a consequence, phases appear at tree level only in the soft
supersymmetry breaking matrices. Using a U(2) flavor model as an example we
show that it is possible to generate radiatively the first and second
generation of quark masses and mixings as well as the CKM CP phase. The
one-loop supersymmetric contributions to EDMs are automatically zero since all
the relevant parameters in the lagrangian are flavor conserving and as a
consequence real. The size of the flavor and CP mixing in the susy breaking
sector is mostly determined by the fermion mass ratios and CKM elements. We
calculate the contributions to epsilon, epsilon^{prime} and to the CP
asymmetries in the B decays to psi Ks, phi Ks, eta^{\prime} Ks and Xs gamma. We
analyze a case study with maximal predictivity in the fermion sector. For this
worst case scenario the measurements of Delta mK, Delta mB and epsilon
constrain the model requiring extremely heavy squark spectra.Comment: 21 pages, RevTex
Data-Based Decisions Guidelines for Teachers of Students with Severe Intellectual and Developmental Disabilities
Effective practices in student data collection and implementation of data-based instructional decisions are needed for all educators, but are especially important when students have severe intellectual and develop- mental disabilities. Although research in the area of data-based instructional decisions for students with severe disabilities shows benefits for using data, there is limited research to demonstrate teachers in applied settings can acquire the decision-making skills required. The purpose of this research was to demonstrate how teachers from five states acquired a set of data-based decisions implementation guidelines through online professional development. Recommendations for practice and future research are included
An imaging time-of-propagation system for charged particle identification at a super B factory
Super B factories that will further probe the flavor sector of the Standard
Model and physics beyond will demand excellent charged particle identification
(PID), particularly K/pi separation, for momenta up to 4 GeV/c, as well as the
ability to operate under beam backgrounds significantly higher than current B
factory experiments. We describe an Imaging Time-of-Propagation (iTOP) detector
which shows significant potential to meet these requirements. Photons emitted
from charged particle interactions in a Cerenkov radiator bar are internally
reflected to the end of the bar, where they are collected on a compact image
plane using photodetectors with fine spatial segmentation in two dimensions.
Precision measurements of photon arrival time are used to enhance the two
dimensional imaging, allowing the system to provide excellent PID capabilities
within a reduced detector envelope. Results of the ongoing optimization of the
geometric and physical properties of such a detector are presented, as well as
simulated PID performance. Validation of simulations is being performed using a
prototype in a cosmic ray test stand at the University of Hawaii.Comment: 3 pages, 5 figures, submitted to TIPP09 proceeding
Semilinear mixed problems on Hilbert complexes and their numerical approximation
Arnold, Falk, and Winther recently showed [Bull. Amer. Math. Soc. 47 (2010),
281-354] that linear, mixed variational problems, and their numerical
approximation by mixed finite element methods, can be studied using the
powerful, abstract language of Hilbert complexes. In another recent article
[arXiv:1005.4455], we extended the Arnold-Falk-Winther framework by analyzing
variational crimes (a la Strang) on Hilbert complexes. In particular, this gave
a treatment of finite element exterior calculus on manifolds, generalizing
techniques from surface finite element methods and recovering earlier a priori
estimates for the Laplace-Beltrami operator on 2- and 3-surfaces, due to Dziuk
[Lecture Notes in Math., vol. 1357 (1988), 142-155] and later Demlow [SIAM J.
Numer. Anal., 47 (2009), 805-827], as special cases. In the present article, we
extend the Hilbert complex framework in a second distinct direction: to the
study of semilinear mixed problems. We do this, first, by introducing an
operator-theoretic reformulation of the linear mixed problem, so that the
semilinear problem can be expressed as an abstract Hammerstein equation. This
allows us to obtain, for semilinear problems, a priori solution estimates and
error estimates that reduce to the Arnold-Falk-Winther results in the linear
case. We also consider the impact of variational crimes, extending the results
of our previous article to these semilinear problems. As an immediate
application, this new framework allows for mixed finite element methods to be
applied to semilinear problems on surfaces.Comment: 22 pages; v2: major revision, particularly sharpening of error
estimates in Section
Inclusive production in B decays and the Enhancement due to charged technipions
The new contributions to the charmless B decay
from the unit-charged technipions and are estimated.
The technipions can provide a large enhancement to the inclusive branching
ratio: for
and when the effect of QCD gluon anomaly is also
taken into account. The new physics effect is essential to interpret the CLEO
data.Comment: Latex file, 7 pages with two EPS figure
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