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Infra-Red(IR) astronomical databases, namely, IRAS, 2MASS, WISE, and Spitzer,are used to analyze photometric data of 126 carbon stars whose spectra arevisible in the First Byurakan Survey low-resolution spectral plates. Amongthese, six new objects, recently confirmed on the digitized FBS plates, areincluded. For three of them, moderate-resolution CCD optical spectra are alsopresented. In this work several IR color-color diagrams are studied. Early andlate-type C stars are separated in the JHK Near-Infra-Red(NIR) color-colorplots, as well as in the WISE W3-W4 versus W1-W2 diagram. Late N-typeAsymptotic Giant Branch stars are redder in W1-W2, while early-types(CH and Rgiants) are redder in W3-W4 as expected. Objects with W2-W3 > 1.0 mag. showdouble-peaked spectral energy distribution, indicating the existence of thecircumstellar envelopes around them. 26 N-type stars have IRAS Point SourceCatalog(PSC) associations. For FBS 1812+455 IRAS Low-Resolution Spectra in thewavelength range 7.7 - 22.6micron and Spitzer Space Telescope Spectra in therange 5 - 38micro are presented clearly showing absorption features ofC2H2(acetylene) molecule at 7.5 and 13.7micron , and the SiC(silicone carbide)emission at 11.3micron. The mass-loss rates for eight Mira-type variables arederived from the K-[12] color and from the pulsation periods. The reddestobject among the targets is N-type C star FBS 2213+421, which belong to thegroup of the cold post-AGB R Coronae Borealis(R CrB) variables.

Investigation of faint galactic carbon stars from the first Byurakan spectral survey. III. Infrared characteristics