- Access by Xinjiang University
Black Bodies in the Extreme Infra-Red
Phys. Rev. 35, 415 – Published 15 February, 1930
DOI: https://doi.org/10.1103/PhysRev.35.415
Abstract
Absorbing power of various materials of wave-lengths greater than 50μ—For blackening a receiver of a thermocouple for radiation for obtaining pure rotation band spectra, it is desirable to use a material that is an efficient absorber of the extreme infra-red but a poor absorber of radiation of shorter wave-lengths. The absorbing power of 25 materials were tested for radiation of wave-lengths near 4μ and greater than 50μ. Of all the materials tested, white lead, litharge, red phosphorus, powdered glass, copper sulphide, and celestite were found the best for covering a receiver to absorb the extreme infa-red radiation. The 25 materials were tested by painting them on a receiver of a thermocouple which was exposed to extreme infra-red radiation. The same receiver and thermocouple were used throughout the experiment. A D'Arsonval type galvanometer was improved by using a quartz suspension and replacing each conducting lead with silver leaf or gold plated silver ribbon 1μ thick wound in a spiral.
Glass as a source of extreme infra-red radiation.—Hot glass made a good source of extreme infra-red radiation when used with a cold thin glass shutter.
References (6)
- L. L. Holladay, J.O.S.A. 17, 333 (1928)
- G. Hettner, Zeits. f. Physik 47, 499 (1928)
- Paul S. Epstein, Zeits. f. Physik 54, 537 (1929)
- Edison Pettit, Astrophys. J. 61, 163 (1926)
- W. W. Coblentz, B. S. Bull. 2-3, 462 (1906)
- Badger and Cartwright, Phys. Rev. 33, 696 (1929)