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.

Static quantities of a neutral bilepton in the 331 model with right-handed neutrinos

A neutral vector boson can possess static electromagnetic properties provided that the associated field is no self-conjugate. This possibility is explored in the $SU_C(3) X SU_L(3) X U_N(1)$ model with right-handed neutrinos, which predicts a complex neutral gauge boson $Y^0$ in a nontrivial representation of the electroweak group. In this model the only nonvanishing form factors are the CP-even ones, which arise from both the quark and gauge sectors, and contribute to the magnetic dipole and the electric quadrupole moments of this neutral particle.Comment: 10 pages, 6 figures, submitted to Phys. Rev.

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

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

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

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