background: the natural radionuclides are always present in soil and care needs to be taken to minimize the radiation dose to humans. these radionuclides are mostly gamma ray emitting radionuclides which contribute to the radiation dose in long term behavior of radionuclides in soil. health hazards associated with natural radioactivity are of great concern and it is necessary to assess risk due...

Radio Astronomy has added greatly to our understanding of the structure and dynamics of the universe. The cosmic microwave background radiation, considered a relic of the explosion at the beginning of the universe some 18 billion years ago, is one of the most powerful aids in determining these features of the universe. This paper is about the discovery of the cosmic microwave background radiati...

In microelectronics, single failure events sporadically occur which, in some areas, like plane and space navigation, could have catastrophic consequences. Preliminary estimations [1] and more recent experiments [2] indicate a correlation between these events and the Background Neutron Radiation (BNR) [3]. The mechanism of failure is the collision of a neutron from the BNR with an atomic nucleus...

These lectures will attempt to convey the excitement and promise in studies of the microwave radiation left over from the early universe. They are aimed at an audience of experimental high energy physicists. The first lecture will concentrate on how the radiation is characterized, how it and its anisotropies are generated, and the physics that it reveals. The second lecture will concentrate on ...

background: humans beings are continuously exposed to ionizing radiation from natural sources. the main contributors to natural radiation are high-energy cosmic radiation and radioactive nuclides that originates in the earth’s crust. exposure to high levels of radiation can cause serious health effects. in this study an attempt has been made to monitor the levels of environmental background rad...

today, nuclear medicine has rapidly been developed so that in some cases, plays a unique role in diagnosis but unfortunalty in spite of diagnostic and therapeutic advantages, the term “nuclear” can induce worries in patients and society. in this article, base on new documents, we intend to show that this worries has no scientific basis. to produce a realistic view, regarding to radiation protec...

We show the existence of spatially homogeneous but anisotropic cosmological models whose cosmic microwave background temperature is exactly isotropic at one instant of time but whose rate of expansion is highly anisotropic. The existence of these models shows that the observation of a highly isotropic cosmic microwave background temperature cannot alone be used to infer that the universe is clo...

We discuss a unique possibility of generating adiabatic density perturbations and leptogenesis from the spatial fluctuations of the inflaton decay rate. The key assumption is that the initial isocurvature perturbations are created in the right-handed sneutrino sector during inflation which is then converted into adiabatic perturbations when the inflaton decays. We discuss distinct imprints on t...

Radon is a natural gas known to be the main contributor to natural background radiation exposure and second to smoking, a major leading cause of lung cancer. The main source of radon is the soil, but the gas can enter buildings in many different ways and reach high indoor concentrations. Monitoring surveys have been promoted in many countries in order to assess the exposure of people to radon. ...