INDEX 



817 



Radiant energy — continued 

 solar (see Solar radiation) 

 spectral, 79 



standard radiator (see also under Black- 

 body), 79 

 symbols, 79 

 temperature, 70 

 total, earth's surface, 713 



our galaxy, 713 



universe, 713 

 transmission, various substances, 535-556 

 units, 36 



wavelength units, 509 

 Radiation, alpha ray, 653-664 

 beta ray, 653 

 cathode, 653 

 constants, 50, 54, 80 

 cosmic, 651, 653, 710 

 earth's surface, 713 

 electromagnetic (see Radiant energy) 

 extraterrestrial, 449 

 gamma, 653, 672 

 mechanical effects, 671 

 our galaxy, 713 

 radioactivity, 654, 672 

 receivers, 548 

 solar, 721, 723 



over disk, 722 



spectral, outside atmosphere, 721 

 sea level, 723 

 universe, 713 

 Radioactivity, 654, 672 

 actinium family, 678 

 alpha rays, 680 

 artificial, 682 



long life, 667 



slow neutron produced, 667 

 atoms (natural), 672, 680 



number, 672, 680 

 beta rays (see also Beta rays), 672 

 breakdown: character, 672 



decay constant, 673, 675 



rate, 672 



units of, Curie, 672 

 Rutherford, 672 

 danger from, 686, 689 



range, 686, 689 

 disintegration, 672 



units for rate of, 672 

 elements, number, 672 

 emission characteristics, 672 



three rays, 672 

 energy of, 672 



radiated, 689 

 families (natural), 675 



artificial additions, 675 



characteristics, 675 

 actinium (4n + 3), 678 

 neptunium (4n + l), 676 

 thorium (4n), 676 

 uranium (4n+2), 677 

 gamma rays (see also Gamma rays), 653, 



672 

 isotopes, 672 



characteristics, 667 



neutron produced, 667 



Radioactivity — continued 

 life 



range for determination, 618 

 materials, 673, 675 

 age, 679 



alpha-ray spectrum, 680 

 beta-ray spectrum, 683 

 energy emitted by, 689 



radium in equilibrium, 691 

 isotopes, 675 



number, 672 

 natural, 673 



characteristics, 673 

 spectra, 680-689 

 original names of, 675 

 neptunium family, 676 

 protection, distances, 686, 689, 690 

 lead, thickness, 690 

 other materials, 684 

 radiation: alpha rays (see also Alpha 

 rays), 672 

 beta rays (see also Beta rays), 672 

 gamma rays (see also Gamma rays), 



672 

 ionization, 672 

 radium in equilibrium, 691 

 thorium family, 676 

 uranium family, 677 

 Radio propagation, 434 

 antenna array, 434 

 direction control, 434 



formula, 435 

 pattern, 434 

 attenuation, 443 

 coefficient, 442 

 constant, 442 

 formulas, 443 

 ground, 444 

 low frequency, 442 



formula, 442 

 oxygen (atm), 449 

 rain, 449 

 sea water, 444 

 water vapor, 445 

 formulas, 443 



frequency: critical, 444, 445 

 different layers, 448 

 high, 446 

 low, 442 



maximum usable (muf ) : 445 

 2000 km, E-layer, 448 

 4000 km, Fs-layer, 446 

 factors for calculating, 448 

 F2-layer muf, 448 

 other distances, 448 

 path length layers, 448 

 reflection, 444 



different layers, 444 

 frequency, 444 

 ion density, 445 

 layers, 445 



minimum height, 445 

 skip distance, 445 

 Radio radiation, 434 

 directivity, 434 

 extraterrestrial, 449 

 patterns, 434 



