JHKLM photometry - Standard systems, passbands, and intrinsic colors

The relations between colors of the JHKL systems of several observatories are examined, and linear relations are derived for transformation between the (J-K), (J-H), (H-K), and (K-L) colors in the different systems. A homogenized system is proposed, based on the systems of Glass (1984) and Johnson et al. (1966). The homogenized data sets are used to derive intrinsic colors for a number of giants and dwarfs. The passbands of several IR systems are estimated and the synthetic colors of the systems are compared using blackbody and stellar fluxes. The passbands were adjusted in wavelength to produce agreement with observed relations between different systems, making it possible to estimate the effective wavelengths of the different natural systems.