1,268 research outputs found
L.O.V.E. is the Answer: The Movie
The presenter will show a 60-minute, condensed version of their film, âWalking While Black: L.O.V.E. Is The Answer,â followed by a 15-minute question-and-answer of the L.O.V.E. Is The Answer principles that make up the foundation of the film
Implications of the CP asymmetry in semileptonic B decay
Recent experimental searches for , the CP asymmetry in semileptonic B
decay, have reached an accuracy of order one percent. Consequently, they give
meaningful constraints on new physics. We find that cancellations between the
Standard Model (SM) and new physics contributions to mixing
cannot be as strong as was allowed prior to these measurements. The predictions
for this asymmetry within the SM and within models of minimal flavor violation
(MFV) are below the reach of present and near future measurements. Including
order and corrections we obtain the SM
prediction: . Future
measurements can exclude not only the SM, but MFV as well, if the sign of the
asymmetry is opposite to the SM or if it is same-sign but much enhanced. We
also comment on the CP asymmetry in semileptonic decay, and update the
range of the angle in the SM: .Comment: 16 pages, a sign typo in eq.(11) fixed, to appear in Phys. Rev.
Implications of the Top Quark Mass Measurement for the CKM Parameters, and CP Asymmetries
Motivated by the recent determination of the top quark mass by the CDF
collaboration, \mt =174 \pm 10 ^{+13}_{-12} GeV, we review and update the
constraints on the parameters of the quark flavour mixing matrix in
the standard model. In performing our fits, we use inputs from the measurements
of the following quantities: (i) \abseps, the CP-violating parameter in
decays, (ii) \delmd, the mass difference due to the \bdbdbar\ mixing, (iii)
the matrix elements \absvcb and \absvub, and (iv) -hadron lifetimes. We
find that the allowed region of the unitarity triangle is very large, mostly
due to theoretical uncertainties. (This emphasizes the importance of
measurements of CP-violating rate asymmetries in the system.) Nevertheless,
the present data do somewhat restrict the allowed values of the coupling
constant product and the renormalization-scale
invariant bag constant . With the updated CKM matrix we present the
currently-allowed range of the ratio , as well as
the standard model predictions for the \bsbsbar\ mixing parameter \xs and the
quantities , and , which characterize
the CP-asymmetries in -decays. The ALEPH collaboration has recently reported
a significant improvement on the lower limit on the \bs-\bsb mass
difference, (95\% C.L.). This has interesting
consequences for the CKM parameters which are also worked out.
NOTE: this is a revised and updated version of our previous paper.Comment: LaTeX, 27 pages, 16 uuencoded figures (enclosed), CERN-TH.7398/94,
UdeM-GPP-TH-94-0
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An insight into the brand-conscious Saudi generation of âdriftersâ
The underground pastime of drifting, (which takes its name from the intentional skidding and spinning of cars down freeways and in car parks), has achieved cult-status amongst Saudi youth. So much so, that a whole sub-culture has germinated from a petri dish nourished by: creativity, collective individualism, rebellion, and surrogate cultural hybridization. Its effects can be observed in musical tastes, fashion, slang, brand choices and most notably through user generated content and message forums. The following paper offers an insight into the mindset of those involved in these activities, arguing that they represent a distinct homogenous consumer segment. Secondly, that they seek a type of achievement motivation which encourages participation and brand consumption â as part of a quest for authenticity and global acceptance. Authenticity is a complicated construct, which also includes battling Socio-Religious stereotypes, held by others. Data was collected using three types of participation observation method and in-depth interviews
The exclusive B_s -> phi mu+ mu- process in a constituent quark model
We consider the exclusive B_s -> phi mu+ mu- process in the standard model
using a constituent quark loop model approach together with a simple
parameterization of the quark dynamics. The model allows to compute the decay
form factors and therefore can give predictions for the decay rates, the
invariant mass spectra and the asymmetries. This process is suppressed in the
standard model but can be enhanced if new physics beyond the standard model is
present, such as flavor-violating supersymmetric models. It constitutes
therefore an interesting precision test of the standard model at forthcoming
experiments.Comment: 17 pages, 6 figures, 5 tables, LaTeX; minor changes to the
introduction, table III and figure 3. Few references adde
Two-loop matching of the dipole operators for and
The order corrections to the Wilson coefficients of the dipole
operators () at the matching scale are a crucial ingredient
for a complete next- to-leading logarithmic calculation of the branching ratio
for . Given the phenomenological relevance and the fact that
this two-loop calculation has been done so far only by one group [1], we
present a detailed re-calculation using a different method. Our results are in
complete agreement with those in ref. [1].Comment: 24 pages, latex, 6 figures include
The 2004 UTfit Collaboration Report on the Status of the Unitarity Triangle in the Standard Model
Using the latest determinations of several theoretical and experimental
parameters, we update the Unitarity Triangle analysis in the Standard Model.
The basic experimental constraints come from the measurements of |V_ub/V_cb|,
Delta M_d, the lower limit on Delta M_s, epsilon_k, and the measurement of the
phase of the B_d - anti B_d mixing amplitude through the time-dependent CP
asymmetry in B^0 to J/psi K^0 decays. In addition, we consider the direct
determination of alpha, gamma, 2 beta + gamma and cos(2 beta) from the
measurements of new CP-violating quantities, recently performed at the B
factories. We also discuss the opportunities offered by improving the precision
of the various physical quantities entering in the determination of the
Unitarity Triangle parameters. The results and the plots presented in this
paper can also be found at http://www.utfit.org, where they are continuously
updated with the newest experimental and theoretical results.Comment: 32 pages, 17 figures. High resolution figures and updates can be
found at http://www.utfit.org v2: misprints correcte
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