Library Subscription: Guest

ISSN Online: 2377-424X

International Heat Transfer Conference 5
September, 3-7, 1974, Tokyo, Japan

EXPERIMENTAL MEASUREMENTS OF THE MONOCHROMATIC NEAR NORMAL REFLECTANCE OF GOLD AT CRYOGENIC TEMPERATURES

Get access (open in a dialog) DOI: 10.1615/IHTC5.3270
pages 16-20

Abstract

An experimental apparatus for the measurement of the absolute monochromatic near normal reflectance of metals in the temperature range 300°K to 1°K is described. Thin metal films, approximately 1200° A thick, are vacuum deposited on four sapphire substrates and are arranged so that a beam of monochromatic radiation in the wavelength range 0.7 to 30µ at near normal incidence experiences 8 reflections from the sample surfaces. The monochromatic near normal reflectance or emittance can be calculated from the detector output with the samples in the beam and the samples out of the beam. Experimental values of the monochromatic near normal emittance of gold at 300°K, 79°K, and 6°K are presented and compared with existing data.