The dependence of the lateral distribution of Cherenkov light in simulated extensive air showers to the energy and the mass of the primary cosmic rays has been studied. It has been shown that a previous claim about mass independent proportionality of shower energy to the total Cherenkov photon number is not valid in energies below EEAS ~ 1014 eV. We have found that the core distance of the so c...

Two classes of metrics obtained from non-Riemannian gravitational collapse are presented.The first is the Taub planar symmetric exact solutions of Einstein-Cartan field equations of gravity describing torsion walls which are obtained from gravitational collapse of time dependent perturbation of Riemannian Taub symmetric solutions of General Relativity.The second is a modification of the Vilenki...

Cosmic Rays (CR) travel at speeds essentially indistinguishable from the speed of light. However whilst travelling through magnetic fields, both regular and turbulent, they are delayed behind the light since they are usually charged particles and their paths are not linear. Those delays can be so long that they are an impediment to correctly identifying sources which may be variable in time. Fu...

wewanttofindthecosmologicalconstantinfluenceoncosmicmicrowavebackground(cmb)temperatureduetomovinglinearcosmicstrings.usingthespace-timemetricofalinearcosmicstringinanacceleratedexpandinguniverse,thegott-kaiser stebbins(gks)effect,asanimportantmechanisminproducingtemperaturediscontinuityinthe(cmb),isconsidered;then,itsmodificationduetotheeffectofthecosmologicalconstantiscalculated.theresultshowsthat...

The Large Scale Structure (LSS) in the galaxy distribution is investigated using the Sloan Digital Sky Survey Early Data Release (SDSS EDR). Using the Minimal Spanning Tree technique we have extracted sets of filaments, of wall-like structures, of galaxy groups, and of rich clusters from this unique sample. The physical properties of these structures were then measured and compared with the exp...

Cosmic balloons, consisting of relativistic particles trapped inside a spherical domain wall, may be created in the early universe. We calculate the balloon mass M as a function of the radius R and the energy density profile, ρ(r), including the effects of gravity. At the maximum balloon mass 2GM/R ≈ 0.52 for any value of the mass density of the wall. [email protected] Domain walls may fo...

Galaxies are arranged in interconnected walls and filaments forming a cosmic web encompassing huge, nearly empty, regions between the structures. Many statistical methods have been proposed in the past in order to describe the galaxy distribution and discriminate the different cosmological models. We present in this paper results relative to the use of new statistical tools using the 3D isotrop...

abstractbackground: there are relatively rich uranium mines in regions of saghand and bafgh in yazd province. this survey was carried out to provide a map of ambient gamma radiation of yazd province and the probable effects of the existence of these mines on background radiation dose rates.materials and methods: the measurements of the outdoor and indoor–environmental exposures (including cosmi...

Domain walls, arising from the spontaneous breaking of a discrete symmetry, can be coupled to charge carriers. In much the same way as the Witten model for superconducting cosmic string, an investigation is made here in the case of U(1) × Z2 → U(1), where a bosonic charge carrier is directly coupled to the wall-forming Higgs field. All internal quantities, such as the energy per unit surface an...