Thomsonn.
/ˈtɒmsən/ 1. Physics. Thomson effect: the effect an electric current has, when flowing in the direction of a temperature gradient, of absorbing or giving out heat independently of the Joule heating; so Thomson coefficient, a numerical measure of this effect for a material.
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the world > matter > physics > electromagnetic radiation > electricity > resistance > [noun] > independent effect
Thomson effect1878
the world > matter > physics > electromagnetic radiation > electricity > resistance > [noun] > independent effect > measurement of
Thomson coefficient1906
1878 Encycl. Brit. VIII. 98/1 This anomaly led Tait to the discovery..that the Thomson effect in iron changes its sign..at a temperature near low red heat.
1906 Sci. Abstr. A. 9 481 The Thomson-, Peltier-, and Seebeck-effects may be combined in one diagram, and the author does this for the case of iron and silver.
1930 Engineering 9 May 596/2 The Thomson and Peltier coefficients were given values of the right general order of magnitude.
1966 C. R. Tottle Sci. Engin. Materials vi. 130 By choosing appropriate values of the Peltier and Thomson coefficients, two dissimilar materials can be arranged to produce a substantial e.m.f. if one junction is maintained at a high temperature and the other at a lower one.
1975 D. G. Fink Electronics Engineers' Handbk. xxvii. 3 At large values of dT/dx the Thompson effect may be comparable with the Seebeck effect and must be taken into account in the design of generators and refrigerators.
2. Zoology. Used in the possessive (rarely attributively) to designate an East African gazelle with a broad black lateral stripe, Gazella thomsoni, first collected by him and named in his honour by A. Günther in 1884 ( Ann. & Mag. Nat. Hist. 14 428).
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the world > animals > mammals > group Ungulata (hoofed) > group Ruminantia (sheep, goats, cows, etc.) > antelope > [noun] > subfamily Antilopinae > genus Gazella (gazelle) > Gazella thomsonii (Thomson's gazelle)
Thomson1897
tommy1902
1897 Proc. Zool. Soc. 454 Thomson's Gazelle does not..extend beyond a few miles north of Lake Nakuru.
1906 Westm. Gaz. 2 June 2/2 It is a pretty sight to see a herd of the graceful little Thomson's gazelle (locally called Tommies) mingling with a flock of sheep and goats.
1915 T. Roosevelt & E. Heller Life-hist. Afr. Game Animals II. xviii. 600 The Thomson gazelle is essentially a highland antelope.
1969 Daily Tel. 13 Aug. 17/3 A Thomson's gazelle, born at Whipsnade Zoo, brings the number in the herd..to 20.
1980 R. W. Hayman tr. Haltenorth & Diller Field Guide Mammals Afr. 94 Thomson's Gazelle..horns lyre-shaped and weakly S-formed.
3. Physics. Thomson scattering: scattering of light by free charged particles, spec. electrons, in accordance with classical mechanics.
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the world > matter > physics > electromagnetic radiation > light > refraction > [noun] > scattering
scattering1866
Rayleigh scattering1925
Thomson scattering1935
scatter1942
the world > matter > physics > atomic physics > particle physics > particle avoiding strong interaction > electron > [noun] > scattering by free particles
Thomson scattering1935
1935 Compton & Allison X-Rays in Theory & Exper. (ed. 2) iv. 298 This classical scattering from a free electron is often called ‘J. J. Thomson scattering’.
1935 Compton & Allison X-Rays in Theory & Exper. (ed. 2) Index 827/2 Thomson scattering.
1962 Sci. Survey 3 123 Knowing the brightness of the corona and, from the theory of Thomson scattering, the proportion of sunlight scattered towards the observer by each electron, we can calculate the number of electrons per cubic centimetre.
1978 Nature 19 Jan. 220/1 One..expects that up to a certain radial distance from the accretion column the neutron star surface is covered by a dense atmosphere and represents a ‘tarnished mirror’, reflecting quasi-isotropically by Thomson scattering.
This entry has not yet been fully updated (first published 1986; most recently modified version published online June 2021).
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n.1878