Infrared Stellar Photometry.

A new system of infrared stellar photometry, with approximate effective wavelengths of 2.2 and 3.6 , has been established. Observational data at these two wavelengths, which are designated by K and L and given for more than fifty stars of spectral types ranging from OS to M6. From the combination of these new data with previously published multicolor photometry, revised effective temperatures and bolometric corrections for stars of spectral class FS and later have been derived. The new temperatures are somewhat higher than previous ones, particularly for the early K giants and the M dwarfs; the bolometric corrections for the late-type stars are considerably smaller than those derived by Kuiper but are similar to those derived by .