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The Sunyaev–Zel'dovich effect shows the phenomena of radiant cosmic background radiation interacting with "electron" clouds distorting the spectrum of the radiation. There is also background radiation in the infrared , x-rays , etc., with different causes, and they can sometimes be resolved into an individual source.
1930s – Cosmologist Erich Regener calculates that the non-thermal spectrum of cosmic rays in the galaxy has an effective temperature of 2.8 K. [61] 1931 – Term microwave first used in print: "When trials with wavelengths as low as 18 cm. were made known, there was undisguised surprise+that the problem of the micro-wave had been solved so soon."
In diagnostic radiology, the F-factor is the conversion factor between exposure to ionizing radiation and the absorbed dose from that radiation. In other words, it converts between the amount of ionization in air (roentgens or, in SI units, coulombs per kilogram of absorber material) and the absorbed dose in air (rads or grays).
The Cosmic Background Explorer (COBE / ˈ k oʊ b i / KOH-bee), also referred to as Explorer 66, was a NASA satellite dedicated to cosmology, which operated from 1989 to 1993.Its goals were to investigate the cosmic microwave background radiation (CMB or CMBR) of the universe and provide measurements that would help shape the understanding of the cosmos.
The limit was independently computed in 1966 by Kenneth Greisen, [3] Georgy Zatsepin, and Vadim Kuzmin [4] based on interactions between cosmic rays and the photons of the cosmic microwave background radiation (CMB). They predicted that cosmic rays with energies over the threshold energy of 5 × 10 19 eV would interact with cosmic microwave ...
The co-moving wavenumber corresponding to the maximum power in the mass power spectrum is determined by the size of the cosmic particle horizon at the time of matter-radiation equality, and therefore depends on the mean density of matter and to a lesser extent on the number of neutrino families (), = (/) =, for = .
In astroparticle physics, an ultra-high-energy cosmic ray (UHECR) is a cosmic ray with an energy greater than 1 EeV (10 18 electronvolts, approximately 0.16 joules), [1] far beyond both the rest mass and energies typical of other cosmic ray particles. The origin of these highest energy cosmic ray is not known.
The "Big Bang" scenario, with cosmic inflation and standard particle physics, is the only cosmological model consistent with the observed continuing expansion of space, the observed distribution of lighter elements in the universe (hydrogen, helium, and lithium), and the spatial texture of minute irregularities (anisotropies) in the CMB radiation.