Design and Construction of a Blackbody and its Use in the Calibration of a Grating Spectroradiometer

A blackbody was constructed of graphite which could be inductively heated in an atmosphere of helium to a maximum temperature of 2700°K. This blackbody was used as a source of radiant energy in the calibration of a grating spectroradiometer. The calibration was made over the spectral range of 2600 to 3800 A in the second order, and of 3300 to 7550 A in the first order. The accuracy of the calibrations was estimated to be of the order of 9% in the regions 2600 to 2800 A in the second order, and 7000 to 7550 A in the first order, and of 5% in the regions 2800 to 3800 A in the second order, and 3300 to 7000 A in the first order.