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Cosmic Microwave Background Radiation
Reviews of Modern Physics, 1999Most astronomers and physicists now believe that we live in an expanding universe that evolved from an early state of extremely high density and temperature. Measurements of the spectrum and anisotropy of the cosmic microwave background radiation (CMBR) provide strong evidence supporting this picture. Today, the spectrum of the CMBR matches that of a 2.
David R. Wilkinson, Lyman A. Page
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Radiation in a massive Schwarzschild background
Physical Review D, 1991We investigate the possibility of an important physical consequence arising from a recent theoretical observation by Kundu. This concerns the suppression of gravitational radiation from a weak source in the presence of a massive Schwarzschild background. We conclude that this result appears to be unlikely.
Ezra T. Newman +2 more
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The microwave background radiation
Nuclear Physics B - Proceedings Supplements, 1992The microwave background radiation was first detected in 1965 by A. Penzias and R. Wilson, who received the 1978 Nobel Prize for Physics for this measurement [see Wilson (1983b) for his delightful account of this discovery].
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Radiation of the cosmic background
Astrophysics and Space Science, 1992Radiation of cosmic background can be the result of permanent constant maximum possible creation of matter δ=c3/2G. It becomes the background in the era of matter and is determined by the entropy of the Universe and its parameters.
Vladimir Skalsky, Miroslav Súkeník
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A unique high natural background radiation area - Dose assessment and perspectives.
Science of the Total Environment, 2021M. Hosoda +23 more
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Soviet Atomic Energy, 1988
The data presented show that the yearly background dose equals on the average about 2 mSv (200 mrem). Two thirds of the dose is attributable to internal radiation from natural radionuclides—primarily the decay products of radon and thoron, entering the human body with inhaled air.
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The data presented show that the yearly background dose equals on the average about 2 mSv (200 mrem). Two thirds of the dose is attributable to internal radiation from natural radionuclides—primarily the decay products of radon and thoron, entering the human body with inhaled air.
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Scars on the Cosmic Background Radiation?
The Astrophysical Journal, 1998We ask whether the universe can be a patchwork consisting of distinct regions of matter and antimatter. In previous work, we demonstrated that postrecombination matter-antimatter contact near regional boundaries leads to an observable (but unobserved) gamma-ray flux for domain sizes of less than a few thousand megaparsecs, thereby excluding such ...
A. De Rújula +2 more
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Spectrum of the Cosmic Background Radiation
Annals of the New York Academy of Sciences, 1984Distortions of the spectrum of the cosmic background radiation from a Planckian shape may be expected for a variety of physical reasons. Presently available experimental data are compared.
SIRONI G +7 more
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1998
Space is not dark and empty but filled with radiation. Most of its energy lies in the microwave region of the spectrum, near wavelengths of about 1 or 2 millimeters, coming evenly from all directions. This light, called the “cosmic microwave background radiation,” is left over from the Big Bang.
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Space is not dark and empty but filled with radiation. Most of its energy lies in the microwave region of the spectrum, near wavelengths of about 1 or 2 millimeters, coming evenly from all directions. This light, called the “cosmic microwave background radiation,” is left over from the Big Bang.
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Physics Background and Radiation Exposure
2010This chapter outlines the physical background of cardiac CT and different scanning approaches including aspects of radiation exposure. Several measures are instrumental for reducing radiation exposure from cardiac CT: prospective ECG triggering of acquisitions, short scan lengths, reduction of tube voltage as much as feasible, and individual adjustment
M. Dewey, J. Geleijns
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