Protons accelerated in the internal shocks of a long duration gamma ray burst can escape the fireball as cosmic rays by converting to neutrons. Hadronic interactions of these neutrons inside a stellar wind bubble created by the progenitor star will produce TeV gamma rays via neutral meson decay and synchrotron radiation by charged pion-decay electrons in the wind magnetic field. Such gamma rays...

The origin of the cosmic rays has been a great mystery since they were discovered by Victor Hess in 1912. AGASA’s observation of ultra-high-energy cosmic-rays (UHECR) possibly beyond the GZK (Greisen, Zatsepin and Kuzmin) cutoff stimulated the field in great deal. In addition, Kamiokande’s detection of neutrinos from SN1987A and the H.E.S.S.’s detection of TeV gamma-rays from supernova remnants...

l%A~ 45. All roentgenologists are deeply interested in the problems which may be formulated in these few questions: Do the hard x-rays follow a straight and narrow path from the x-ray target through the tissues of the human body? Do these hard x-rays suffer from reflection or refraction and therefore influence tissues outside of this direct path-way? What factor is secondary radiation in the tr...

Late into the evening of 8 November 1895 Wilhelm Conrad Röntgen, a physics professor at the University of Würzburg, made a discovery that would revolutionize science almost overnight. While conducting experiments with cathode rays in his laboratory, he remarked a peculiar glow with highly unusual properties emanating from a nearby fluorescent screen, the source of which he could not identify. T...

A review of medical diagnostic imaging methods utilizing x-rays or gamma rays and the application and development of inorganic scintillators is presented.

Recently we have shown that the observed knee structure is reproduced well by a superposition of the hypothetical extragalactic cosmic rays modulated by the galactic wind and the galactic cosmic rays originating in supernova remnants. We reexamine this model assuming the chemical composition of the hypothetical extragalactic cosmic rays is the same as that of the galactic cosmic rays of superno...

background: lead-based radiation shields are widely used in radiology departments to protect both workers and patients from any unnecessary exposure to ionizing radiation. recently there has been a great deal of concern expressed about the toxicity of lead. human lead toxicity is well documented. in that light, production of environmentally-friendly lead-free radiation shields with less weight ...

In this paper, we consider the asymptotic behavior of two Teichmüller geodesic rays determined by Jenkins-Strebel differentials, and we obtain a generalization of a theorem by the author in On behavior of pairs of Teichmüller geodesic rays, 2014 . We also consider the infimum of the asymptotic distance up to choice of base points of the rays along the geodesics. We show that the infimum is repr...

Far-infrared rays have certain kinds of effects on the human body, especially on skin, blood circulation, and skin cell vitalizing. Some jewelry powders radiate far-infrared rays. Jade has powerful far-infrared ray radiation, and tourmaline has pyroelectric and piezoelectric properties and radiated far-infrared rays. The jewelry powders (fine powdered jade and tourmaline powders) were screened ...