Narrow Results

Two methods for determining $\left|V_{us}\right|$ employing inclusive hadronic $\tau$ decay data are discussed. The first is the conventional flavor-breaking sum rule determination whose usual implementation produces results $\sim 3\sigma$ low compared to three-family unitary expectations. The second is a novel approach combining experimental strange hadronic $\tau$ distributions with lattice light-strange current–current two-point function data. Preliminary explorations of the latter show the method promises $\left|V_{us}\right|$ determinations competitive with those from $K_{\ell 3}$ and $\mathrm{\Gamma }[K_{\mu 2}]/\mathrm{\Gamma }[{\pi }_{\mu 2}]$. For the former, systematic issues in the conventional implementation are investigated. Unphysical dependences of $\left|V_{us}\right|$ on the choice of sum rule weight, $w$, and upper limit, $s_0$, of the weighted experimental spectral integrals are observed, the source of these problems identified and a new implementation which overcomes these problems developed. Lattice results are shown to provide a tool for quantitatively assessing truncation uncertainties for the slowly converging $D=2$ OPE series. The results for $\left|V_{us}\right|$ from this new implementation are shown to be free of unphysical $w$- and $s_0$-dependences, and $\sim 0.0020$ higher than those produced by the conventional implementation. With preliminary new $K\pi$ branching fraction results as input, we find $\left|V_{us}\right|$ in excellent agreement with that obtained from $K_{\ell 3}$, and compatible within errors with expectations from three-family unitarity.

A measurement of the ratio of branching fractions, R = B(t→Wb)/B(t→Wq), with q being any quark with I₃ = -1/2 and Q = -1/3, is presented. This analysis considers samples of single- and double-tagged lepton+jets events obtained with the DØ detector, corresponding to integrated luminosities of 169 pb^-1 and 158 pb^-1, respectively in the e+jets and μ+jets channels. Two different lifetime taggers, CSIP and SVT, are used.

Precision tests of the Kobayashi–Maskawa model of CP violation are discussed, pointing out possible signatures for other sources of CP violation and for new flavor-changing operators. The current status of the most accurate tests is summarized.

Flavour mixing is described within the Standard Model by the Cabibbo–Kobayashi–Maskawa (CKM) matrix elements. With the increasingly higher statistics collected by many experiments, the matrix elements are measured with improved precision, allowing for more stringent tests of the Standard Model. In this paper, a review of the current status of the absolute values of the CKM matrix elements is presented, with particular attention to the latest measurements.

This paper analyses the Customer Knowledge Management (CKM) conceptual structures existing within the literature, to identify its current state of research and extract from it, important elements that enable the construction of a CKM framework. To accomplish this, a six-step systematic literature review was performed, thus selecting 27 articles with CKM structures, which were fully inspected by using Thematic Analysis at the end. As main results, this study displays a detailed synthesis of the main elements for CKM and exposes a CKM framework composed of four dimensions, namely, Planning, Acquisition, Intelligence and Value Generation. Each dimension comprises specific processes and activities that can assist CKM managers and researchers in managing, collecting, analysing, storing, and sharing the customer knowledge. Finally, this research also presents a set of tools, methods and techniques that can be used in each of the framework processes.

Almost two decades after its discovery at Fermilab's Tevatron collider experiments, the top quark is still under the spotlight due to its connections to some of the most interesting puzzles in the Standard Model. The Tevatron has been shut down two years ago, yet some interesting results are coming out of the CDF and D0 collaborations. The LHC collider at CERN produced two orders of magnitude more top quarks than Tevatron's, thus giving birth to a new era for top quark physics. While the LHC is also down at the time of this writing, many top quark physics results are being extracted out of the 7 TeV and 8 TeV proton proton collisions by the ATLAS and CMS collaborations, and many more are expected to appear before the LHC will be turned on again sometime in 2015. These proceedings cover a selection of recent results produced by the Tevatron and LHC experiments.

We review recent measurements of kaon decays and lifetimes for the determination of the CKM element V_us. Their relevance to CKM matrix unitarity is discussed.