Renormalization of the Cabibbo-Kobayashi-Maskawa Quark Mixing Matrix

We have investigated the present renormalization prescriptions of Cabibbo-Kobayashi-Maskawa (CKM) matrix. When considering the prescription which is formulated with reference to the case of zero mixing we find it doesn't satisfy the unitary condition of the bare CKM matrix. After added a delicate patch this problem can be solved at one-loop level. In this paper We generalize this prescription to all loop levels and keep the unitarity of the bare CKM matrix, simultaneously make the amplitude of an arbitrary physical process involving quark mixing convergent and gauge independent. We also find that in order to keep the CKM counterterms gauge independent the unitarity of the bare CKM matrix must be preserved.Comment: has been revised, 8 pages, 1 figur

Note on CKM Matrix Renormalization

A simple inspection of the one loop quark self-energy suggests a prescription of the CKM matrix renormalization in the standard model. It leads to a CKM matrix counterterm which is gauge parameter independent and satisfies the unitarity constraint, and renormalized physical amplitudes which are gauge parameter independent and smooth in quark mass difference. We make a point that caution should be practiced when interpreting the CKM martix counterterm in terms of those of parameters in a given representation due to rephasing effects from renormalization. We show how this can be done using the degrees of freedom in the on-shell renormalization scheme.Comment: version 1: 10 pages, no figures; version 2: proofread version for Phys Rev D with minor revisions: (1) divided into 3 sections; (2) added a footnote Comment on Ref. [8] as Ref. item [13]; (3) typos fixed and minor rewordin

Electroweak Corrections to the Top Quark Decay

We have calculated the one-loop electroweak corrections to the decay t-> bW+, including the counterterm for the CKM matrix elements V(tb). Previous calculations used an incorrect delta V(tb) that led to a gauge dependent amplitude. However, since the contribution stemming from delta V(tb) is small, those calculations only underestimate the width by roughly one part in 10^5.Comment: 7 pages, 2 figure

Properties of gypsum-PCM based mortars for interior plastering of construction systems

Incorporating phase change materials (PCM) in plasters is an effective solution both for more efficient use of energy and its consumption reduction, because it allows the use of free energy in the environment, by latent heat storage. As PCM has not binder properties, it is expected to decrease mechanical properties of the final mortar. Also the density of the mortar decreases due to PCM lighter specific weight. In order to be used as a final coat for wall plastering, it must verify the requirements of the respective European Standard. This paper presents the results of the composition development and mechanical properties (flexural, compressive and adhesive strengths) testing and validation of three different gypsum mortars, in order to select the appropriate one for thermal testing in test cells. The results show that the effective decrease in the studied characteristics of the mortar does not inhibit the use for plastering, as requirements are achieved by the three studied compositions.Agência de Inovação (ADI

The Fornax Deep Survey with VST. VIII. Connecting the accretion history with the cluster density

This work is based on deep multi-band (g, r, i) data from the Fornax Deep Survey with VST. We analyse the surface brightness profiles of the 19 bright ETGs inside the virial radius of the Fornax cluster. The main aim of this work is to identify signatures of accretion onto galaxies by studying the presence of outer stellar halos, and understand their nature and occurrence. Our analysis also provides a new and accurate estimate of the intra-cluster light inside the virial radius of Fornax. We performed multi-component fits to the azimuthally averaged surface brightness profiles available for all sample galaxies. This allows to quantify the relative weight of all components in the galaxy structure that contribute to the total light. In addition, we derived the average g-i colours in each component identified by the fit, as well as the azimuthally averaged g-i colour profiles, to correlate them with the stellar mass of each galaxy and the location inside the cluster. We find that in the most massive and reddest ETGs the fraction of light in, probably accreted, halos is much larger than in the other galaxies. Less-massive galaxies have an accreted mass fraction lower than 30%, bluer colours and reside in the low-density regions of the cluster. Inside the virial radius of the cluster, the total luminosity of the intra-cluster light, compared with the total luminosity of all cluster members, is about 34%. Inside the Fornax cluster there is a clear correlation between the amount of accreted material in the stellar halos of galaxies and the density of the environment in which those galaxies reside. By comparing this quantity with theoretical predictions and previous observational estimates, there is a clear indication that the driving factor for the accretion process is the total stellar mass of the galaxy, in agreement with the hierarchical accretion scenario.Comment: 18 pages, 10 figures. Accepted for publication in A&

Inelaticity in hadron-nucleus collisions from emulsion chamber studies

The inelasticity of hadron-carbon nucleus collisions in the energy region exceeding 100 TeV is estimated from the carbon-emulsion chamber data at Pamirs to be $= 0.65\pm 0.08$. When combined with the recently presented data on hadron-lead nucleus collisions taken at the same energy range it results in the $K\sim A^{0.086}$ mass number dependence of inelasticity. The evaluated partial inelasticity for secondary ($\nu > 1$) interactions, $K_{\nu >1} \simeq 0.2$, suggests that the second and higher interactions of the excited hadron inside the nucleus proceed with only slight energy losses.Comment: LaTeX file and 5 LaTeX files with figures, 11 pages altogether. Thoroughly rewritten and modified, one figure addded one removed. To be published in Phys. Rev.

Investigação experimental sobre composição, resistência mecânica e capacidade de auto-limpeza de argamassas fotocatalíticas

The self-cleaning ability of photocatalytic cement-based materials has the potential to preserve the esthetic appearance of building facades over time thus reducing cleaning costs. In the present work , the joint effect of several factors on the mechanical strength and self-cleaning ability of photocatalytic mortars was studied. For this purpose, four different mortar mixes containing two binder/sand ratios (1:3 and 1:4) were analyzed. Two mixes containing only Portland cement and the other two possessing 50% Portland cement and 50% aerial lime. For each mix, four different compositions were manufactured, each one with a different titanium dioxide-TiO2 content (0%, 2%, 4% and 6%). The results show that w/b increases with TiO2 which, in turn, leads to lower mechanical strength. Results also show that the mixes with 2% TiO2 had the highest self-cleaning effect.A capacidade de auto-limpeza de materiais cimentícios fotocatalíticos apresenta potencial para preservar a aparência estética das fachadas de edificios ao longo do tempo reduzindo dessa forma os custos de limpeza das mesmas. No presente trabalho estudou-se o efeito conjunto de vários factores na resistência mecãnica e na capacidade de auto-limpeza de argamassas fotocatalíticas. Para este objectivo analisaram-se quatro argamassas contendo dois rácios ligante/areia (1:3 e 1:4). Duas composições continham sómente cimento Portland e outras duas continham 50% de cimento Portland e 50% de cal aérea. Para cada uma destas composições produziram-se quatro misturas com uma percentagem variável de dióxido de titânio - TiO2 (0%, 2%, 4% e 6%). Os resultados mostram que o aumento da percentagem de TiO2 implica um aumento da razão água/ligante que se traduz em menor resistência mecânica. Os resultados mostram também que as argamassas com 2% de TiO2 apresentaram a maior capacidade de auto-limpeza.info:eu-repo/semantics/publishedVersio

Threshold Behaviour in Gauge Boson Pair Production at LEP 2

We discuss the form of the amplitude for gauge boson pair production at or near threshold.We show that in the case of W-pair production at LEP2 near threshold only one anomalous electromagnetic coupling can contribute. This anomalous coupling is CP violating and contributes to the electric dipole moment of the $W$. Since this coupling is likely to be small, it is important to look for ZZgamma couplings in Zgamma production. These couplings are not suppressed at the W-threshold