Results 221 to 230 of about 190,695 (272)

Scattered radiation from a neutron collimator

Medical Physics, 1977
Fast‐neutron beams are being employed in radiotherapy trials and associated radiobiology studies at numerous centers in the U.S., Europe, and Japan. Since collimated beams of various sizes and shapes are employed, it is desirable to know the composition of the scattered radiation component contributed by the collimator.
F H, Attix, L S, August, P, Shapiro
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Measurements of neutron radiation in aircraft

Applied Radiation and Isotopes, 2010
Radiation environment is a complex mixture of charged particles of the solar and galactic origin, as well as of secondary particles created in an interaction of galactic cosmic particles with the nuclei of the Earth's atmosphere. A radiation field at aircraft altitude consists of different types of particles, mainly photons, electrons, positrons and ...
Vuković, Branko, Poje Sovilj, Marina, Varga Pajtler, Maja, Radolić, Vanja, Miklavčić, Igor, Faj, Dario, Stanić, Denis, Planinić, Josip   +7 more
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Physics intercomparisons for neutron radiation therapy

International Journal of Radiation Oncology*Biology*Physics, 1977
Abstract For several years, a concerted effort has been going on to ensure that all the groups involved in neutron dosimetry have intercompared their absorbed dose standards. These intercomparisons have relevance to both neutron radiotherapy and neutron radiobiology.
P R, Almond, J B, Smathers
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Treatment planning for neutron radiation therapy

International Journal of Radiation Oncology*Biology*Physics, 1977
Abstract Treatment-planning techniques developed for photon therapy have been freely borrowed for fast-neutron beam therapy, including methods of storing the measured data and subsequent manipulation to correct for patient contour, inhomogeneities, oblique incidence of the beam, and the presence of beam-modifying devices.
P, Wootton, K, Weaver, J, Eenmaa
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Microdosimetric Specification of Radiation Quality in Neutron Radiation Therapy

International Journal of Radiation Biology, 1990
The neutron beams used by various radiotherapy centres are of widely differing energies, and differences of up to 50 per cent in the relative biological effectiveness (RBE) between different beams have been found in radiobiological experiments. Moreover, at some facilities RBE variations have been observed with increasing depth in a phantom.
H G, Menzel, P, Pihet, A, Wambersie
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Neutron Radiation Measurements on Several International Flights

Health Physics, 2015
The earth is continually exposed to cosmic radiation of both solar and galactic origin. High-energy particles interact with the constituents in the atmosphere producing secondary particles that create radiation fields at aircraft altitudes. These secondary particles consist mainly of photons, protons, neutrons, charged and uncharged pions, and muons ...
Poje, Marina, Vuković, Branko, Radolić, Vanja, Miklavčić, Igor, Planinić, Josip   +4 more
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Radiation shielding for neutron guides

Physica B: Condensed Matter, 2006
Abstract Models of the neutron guide shielding for the out of bunker guides on the thermal and cold neutron beam lines of the OPAL Reactor (ANSTO) were constructed using the Monte Carlo code MCNP 4B. The neutrons that were not reflected inside the guides but were absorbed by the supermirror (SM) layers were noted to be a significant source of gammas.
T. Ersez, G. Braoudakis, J.C. Osborn
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Neutron radiation effects in HEMTs

RADECS 93. Second European Conference on Radiation and its Effects on Components and Systems (Cat. No.93TH0616-3), 2002
HEMTs have been irradiated with fast neutrons at fluences up to 10/sup 16/n/cm/sup 2/. At large enough fluences the two dimensional electron gas vanishes and the devices turn into AlGaAs MESFETs. The majority carrier traps responsible for the degradation have been investigated.
G.J. Papaioannou, M. Papastamatiou, N. Arpatzanis, P. Dimitrakis, C. Papastergiou   +4 more
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Thermal radiation of neutron stars

Astrophysics, 1987
The parameters that characterize the thermal evolution of neutron stars whose hadronic matter contains a ..pi../sup -/ meson component are found. It is shown that the surface temperature T/sub R/ of typical neutron stars varies in the range 10/sup 5/ less than or equal to T/sub R/ less than or equal to 10/sup 6/. For T/sub R/ > 10/sup 6/, their cooling
G. G. Arutyunyan, V. V. Papoyan, G. S. Saakyan   +2 more
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White radiation neutron-diffraction techniques

Acta Crystallographica Section A, 1973
In a recent paper Hubbard, Quicksall & Jacobson [Acta Cryst. (1972). A28, 236–245] describe a highly efficient white-radiation neutron-diffraction technique. The present note discusses some of the problems which arise from the use of such techniques in the light of recent measurements at Harwell and emphasizes that, because of these problems, structure
S. A. Wilson, M. J. Cooper
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