We show that the ”puzzling” chemical composition observed in the extremely metal poor star HE0107-5240 may be naturally explained by the concurrent pollution of at least two supernovae. In the simplest possible model a supernova of quite low mass (∼ 15 M⊙), underwent a ”normal” explosion and ejected ∼ 0.06 M⊙ of Ni while a second one was massive enough (∼ 35 M⊙) to experience a strong fall back...

Optical spectroscopy and photometry of SN 2006aj have been performed with the Subaru telescope at t > 200 days after GRB060218, the X-ray Flash with which it was associated. Strong nebular emission-lines with an expansion velocity of v ∼ 7, 300 km s were detected. The peaked but relatively broad [OI]λλ6300, 6363 suggests the existence of ∼ 2M⊙ of materials in which ∼ 1.3M⊙ is oxygen. The core m...

Nuclear energy is required to provide a reliable, sustainable, and environmentally friendly source. Its use, however, receives limited public support, mainly because of the nuclear disasters that have occurred in past. People perceive it as more dangerous than really does not consider its multiple benefits. In addition their concerns about consequences explosion, there are many other factors af...

Adiabatic and isothermal propagations of spherical blast wave produced due to a nuclear explosion have been studied using the Energy hypothesis of Thomas, in the nonuniform atmosphere of the earth. The explosion is considered at different heights. Entropy production is also calculated along with the strength and velocity of the shock. In both the cases; for adiabatic and isothermal flows, it ha...

The antineutrino is the only real-time nuclear signature from a fission explosion that propagates great distances through air, water, and ground. The size and sensitivity of antineutrino detectors has increased dramatically in the last decade, and will continue to do so in the next, thanks in part to the renewed interest in neutrino physics brought on by the recent discovery that neutrinos may ...

GENERAL CHARACTERISTICS OF energy is initially in the form of kinetic THERMAL RADIATION energy of the weapon debris. This kinetic energy is also absorbed by the air 7.01 One of the important difat a slightly later time \(§ 2.109) and ferences between a nuclear and a conserves to further heat the air. The heated ventional high-explosive weapon is the air, which constitutes the fireball, in turn ...

The nature of two explosions that were witnessed within 3 s at the Chernobyl-4 reactor less than a minute after 21:23:00 UTC on April 25, 1986, have since then been the subject of sprawling interpretations. This paper renders the following hypothesis. The first explosion consisted of thermal neutron mediated nuclear explosions in one or rather a few fuel channels, which caused a jet of debris t...

We investigate the effects of neutrino heating and α-particle recombination on the hydrodynamics of corecollapse supernovae. Our focus is on the non-linear dynamics of the shock wave that forms in the collapse, and the assembly of positive energy material below it. To this end, we perform time-dependent hydrodynamic simulations with FLASH2.5 in spherical and axial symmetry. These generalize our...

background: new technologies using hazardous materials usually have certain risks. it is more serious when the technology is supposed to be applied in a large scale and become widely used by many people. the objective of this paper was to evaluate the risk of vapor cloud explosion in a hydrogen production process. methods: potential hazards were identified using the conventional hazard identifi...