Surface Dislocations and the Growth of Deformation Twins

Phase boundaries in diffusionless phase transformations are defined as surface dislocations. Growth kinetics for deformation twins are discussed in relation to the rate controlling process for the motion of surface dislocations. The elementary process is the nucleation of step rings on surface dislocations. The effect of abnormal elastic properties residing along twinning surface dislocations is taken into account. These abnormalities result from the disturbed atomic arrangement along twinning surface dislocations (twin boundaries). The theory predicts three important features : (1) Twinning deformation is very fast when the applied stress exceeds a critical value. (2) Stress-strain curves will show large yield drops at the start of twinning when the displacement rate is constant. (3) Twinning is more prominent at lower temperatures compared with the slip mode of deformation

Search for Anomalous Couplings in Top Decay at Hadron Colliders

We present a quantitative study on sensitivities to the top-decay anomalous couplings, taking into account realistic experimental conditions expected at Tevatron and LHC. A double angular distribution of W and charged lepton in the top decay is analyzed, using ttbar events in the lepton+jets channel. In order to improve sensitivities to the anomalous couplings, we apply two techniques: (1) We use a likelihood fitting method for full kinematical reconstruction of each top event. (2) We develop a new effective spin reconstruction method for leptonically-decayed top quarks; this method does not require spin information of the antitop side. For simplicity, we neglect couplings of right-handed bottom quark as well as CP violating couplings. The 95% C.L. estimated bound on a ratio of anomalous couplings reads -0.81 < f_2/f_1 < -0.70, -0.12<f_2/f_1<0.14 using 1000 reconstructed top events at Tevatron, while -0.74<f_2/f_1<-0.72, -0.01<f_2/f_1<0.01 is expected with 100k reconstructed top events at LHC, where only statistical errors are taken into account. A two-fold ambiguity in the allowed range remains when the number of events exceeds a few hundred.Comment: 21 pages, 15 figure

Relationship marketing: A survey of architectural offices in Japan

Architectural offices embrace the concept of relationship marketing (RM) in general because relationships are considered important in the provision of professional service. The focus of this study is the examination of relationships that are perceived to be important in the present and the future as well as the examination of their present and future positions in architectural offices in Japan. The data was collected by fieldwork survey and interviews on 19 respondents and then empirically analyzed and linked to a model that combined the Superpositioning matrix and Gummesson's 30Rs. The findings include current trends of position and the relationships that are emphasized in any particular position in the matrix of the architectural offices. Additionally, the findings could suggest some key relationships for the increase of the operating client's and architect's value in a project as well as for managing architectural offices

Singe Top Production at LEP 200

We present exact tree level cross sections for the single top production process $e^- e^+ \rightarrow e^- \bar{\nu}_e t \bar{b}$ at LEP~200. The results reproduce roughly those obtained earlier by using the equivalent real photon approximation and we confirm the observation that detecting a top heavier than half the c.m.~energy is not feasible at LEP~200. The calculation has been performed by a new automatic Feynman amplitude generator MadGraph which produces HELAS code for the helicity amplitudes.Comment: 7 pages, 4 postscript figure

Internal Friction in Deformed Indium Antimonide Crystals(Physics)

The internal friction in deformed InSb single crystals is investigated in the temperature range from 4.2 to 503 K. Three relaxation peaks, denoted by P_1, P_2, and P_3, with activation energies of (0.05±0.01), (0.08±0.01), and (0.36±0.02) eV, respectively, are observed to develop upon deformation. The heights of these peaks decrease gradually upon annealing. Peaks P_1 and P_2 are interpreted to be associated with the stress-induced motion of geometrical kinds on In-dislocations and Sb-dislocations, respectively, passing over the Peierls potential barrier of the second kind. Peak P_3 is interpreted to be due to the interaction of geometrical kinks with jogs located on dislocation lines

Final-State Interactions in e^+e^- -> t\bar{t} -> b l^+ \nu \bar{b} W^- Near Top Quark Threshold

We calculate final-state interaction corrections to the energy-angular distribution of l^+ in semi-leptonic top quark decay, where the parent top quark is produced via e^+e^- -> t\bar{t} near threshold. These are the corrections due to gluon exchange between t and \bar{b} (\bar{t} and b) and between b and \bar{b}. Combining with previously known other corrections, we explicitly write down the l^+ energy-angular distribution including the full O(alpha_s)=O(beta) corrections near t\bar{t} threshold. Numerical analyses of the final-state interaction corrections are given. We find that they deform the l^+ distribution typically at the 10% level. We also find that all qualitative features of the numerical results can be understood from intuitive pictures. The mechanisms of various effects of the final-state interactions are elucidated. Finally we define an observable which is proper to the decay process of the top quark (dependent only on d\Gamma_{t -> b l^+ \nu}/ dE_l d\Omega_l of a free polarized top quark) near t\bar{t} threshold. Such a quantity will be useful in extracting the decay property of the top quark using the highly polarized top quark samples.Comment: Section 6 is enlarged substantially and a paragraph is added to Section 8 correspondingly. Reference list is also improved. (27 pages including figures, LaTeX

Determination of Indium Concentration in GaAs : In Semiconductor by PIXE

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