In this thesis work a complete study of the four quadrants coronagraph is presented This new coronagraph o ers performances of extremely large theorical rejection factor These performances open possibilities of exo planets detection around nearby stars The rst laboratory results gave an attenuation rate higher than on the central peak Thus I naturally studied all the possible uses of this coron...

Abstract The aim of the study was to find out what extent low socio-economic status (SES) children enrolled in government-run primary schools Hyderabad are ready receive instruction through medium English (English [EMI]). To this end we investigated children’s oral vocabulary skills, lexical complexity their textbooks, as well amount input they class. A subsample 90 from school Grades 4 and 5 w...

Azimuthal asymmetries in signals of non vertical showers have been observed in ground arrays of water Cherenkov detectors, like Haverah Park and the Pierre Auger Observatory. The asymmetry in time distributions of arriving particles offers a new possibility for the determination of the mass composition. The dependence of this asymmetry on atmospheric depth shows a clear maximum at a position th...