Specific heat (Cp) of Apiezon N grease, (1 to 108 K) and calorimetry: Cp of copper below 30 K

Heat capacity (C-p) data for Apiezon N grease from 1 to 108 K are compared with previous results for this grease and for Apiezon T, with good agreemen t. Addenda results for a calorimeter in which Apiezon N grease is used for thermal contact between the tray and a sample suggest that a thin film of t his grease has an appreciably larger C-p, below 4 K, than bulk grease. For high accuracy experiments using Apiezon N grease, care should be taken in t he calculation of addenda C-p's from bare tray data and the C-p for bulk gr ease. During these measurements, C-p data for a high purity electron beam m elted copper sample were found to be in excellent agreement from 1 to 30 K (+/-60.2%) with previous measurements [Holste, Cetas, and Swenson, Rev. Sci . Instrum. 43, 670 (1972)] on a different sample using a quite different ca lorimeter. (C) 1999 American Institute of Physics. [S0034-6748(99)02106-1].