Near-infrared photometric analyzes of white dwarf stars

We review the available near- and mid- infrared photometry data sets for white dwarfs from the Two Micron All-Sky Survey (2MASS) Point Source Catalog and the Spitzer Space Telescope. These data sets have been widely used to search for white dwarfs with an infrared excess as well as to characterize the atmosphere of cool white dwarfs. We evaluate the reliability of the 2MASS photometry by performing a statistical comparison with published JHK CIT magnitudes, and by carrying out a detailed model atmosphere analysis of the available photometry. We then present a critical examination of various results published in the literature including data from the Spitzer Space Telescope.