| 释义 |
Lyman Physics.|ˈlaɪmən|
The name of Theodore Lyman (1874–1954), U.S. physicist, used attrib. to designate a series of lines (individually designated alpha, beta, etc.) discovered by him in the ultraviolet part of the spectrum of atomic hydrogen, with wave numbers represented by the formula R(1 - 1/m2) (where R is the Rydberg constant and m = 2, 3,{ddd}), the first line of which has a wavelength of 121·6 nanometres.
1922Encycl. Brit. XXXII. 559/2 The formulæ for the hydrogen series are as follows:—Lyman series: ν = N/12 - N/m2 (m = 2, 3,{ddd}). Balmer series: ν = N/22 - N/m2 (m = 3, 4,{ddd}). Paschen series: ν = N/32 - N/m2 (m = 4, 5,{ddd}). 1929J. K. Robertson Introd. Physical Optics xviii. 359 Lines of the Lyman series arise from electron drops from outer orbits to the innermost or normal orbit, for which k = 1. 1959Sunday Times 5 Apr. 8/3 The sun itself has been photographed in the extreme ultra-violet (the Lyman-alpha) region of the spectrum. 1967W. R. Hindmarsh Atomic Spectra ii. 13 Ritz..proposed his well-known combination principle in 1908; he recognized that the wave-numbers of the lines could always be represented as a difference between two terms... It was with the use of this principle that the Paschen, Lyman, Brackett and Pfund series in the spectrum of hydrogen were predicted..before they were known experimentally. 1968G. M. B. Dobson Exploring Atmosphere (ed. 2) viii. 158 Another possiblity is that the very strong radiation which is given out by hydrogen in the sun, at a wavelength of 1216 Ångstrom units (known as the Lyman alpha line) produces the D region [of the ionosphere]. |