Acceleration and Particle Field Interactions of Cosmic Rays I: Formalism

The acceleration of ultra high energy cosmic rays is conjectured to occur through various interactions with the electromagnetic fields in different astrophysical objects, like magnetic matter clumps, besides the well-known shock and stochastic Fermi mechanisms. It is apparent that the latter are not depending on the particle's charge, quantitatively. Based on this model, a considerable portion of the dynamics, that derives a charged particle parallel to a magnetic field $\mathbf{B}$ and under the influence of a force $\mathbf{F}$, is assumed to be composed of an acceleration by a non-magnetic force $\mathbf{F}_{\parallel}$ and a gyromotion along $\mathbf{B}$ direction, plus drifts in the direction of $\mathbf{F}_{\perp}$. The model and its formalism are introduced. Various examples for drift motions and accelerating forces are suggested. The formalism is given in a non-relativistic version. Obviously, the translation into the relativistic version is standard. In a forthcoming work, a quantitative estimation of the energy gained by charged cosmic rays in various astrophysical objects will be evaluated.Comment: 9 pages, 2 EPS figure

Particle production in proton-proton collisions

Proton-proton collision is a simple system to investigate nuclear matter and it is considered to be a guide for more sophisticated processes in the proton-nucleus and the nucleus-nucleus collisions. In this article, we present a phenomological study of how the mechanism of particle production in pp interaction changes over a wide range of interaction energy. This study is done on data of charged particle produced in pp experiments at different values of energy. Some of these data give the created particles classified as hadrons, baryons and mesons, which help us compare between production of different particles. This might probe some changes in the state of nuclear matter and identify the mechanism of interaction.Comment: arXiv admin note: text overlap with arXiv:1410.715

Interaction of 160 GeV- Muon with Emulsion Nuclei

In this work we present some results of the interaction of high energy muons with emulsion nuclei. The interaction results in emission of a number of fragments as a consequence of electromagnetic dissociation of the excited target nuclei. This excitation is attributed to absorption of photons by the target nuclei due to the intense electric field of the very fast incident muon particles. The interactions take place at impact parameters that allows ultra-peripheral collisions to take place, leading to giant resonances and hence multi-fragmentation of emulsion targets. Charge identification, range, energy spectra, angular distribution and topological cross-section of the produced fragments are measured and evaluatedComment: 13 pages, 4 figures, 4 tables. Accepted for publication in IJMP

The Influence of Institutional and Conductive Aspects on Entrepreneurial Innovation: Evidence from GEM Data

YesPurpose – The main purpose of this study is to improve the understanding of how different aspects of the national institutional environment may influence the level of innovative entrepreneurial activity across countries. Several institutional and conductive factors affecting a country’s capacity to support innovative entrepreneurship is explored. Design/methodology/approach – Institutional theory is used to examine the national regulatory, normative, cognitive, and conducive aspects that measure a country's ability to support innovative entrepreneurship. A cross-national institutional profile is constructed to validate an entrepreneurial innovation model. The impact of country-level national institutions on innovative entrepreneurial activity as measured by Global Entrepreneurship Monitor (GEM) data is assessed through structural equation modeling (SEM). Findings – Knowledge about the influence of specific institutional aspects on innovative entrepreneurship, and hence of institutional structures within and across countries, is enhanced. For new innovative enterprises, conductive and regulatory aspects seem to matter most. All conductive factors have a significant and positive impact on entrepreneurial activity rates. Research limitations/implications – Results could support policy makers and practitioners in evaluating government policies’ effect on innovative entrepreneurship. Interventions should target both individual attributes and context. Future research could include longitudinal designs to measure the direction of causality. Practical implications – Aspects such as regulatory institutions, and conductive factors such as ICT use and technology adoption, are important for innovation entrepreneurship development.The full text will be made available when the article is officially published