A Critical Examination of the Spectrum and the Diffuse Interstellar Bands
نویسندگان
چکیده
It has recently been suggested by J. P. Maier’s group that the origin band and three vibronic bands of the linear propadienylidene anion match the diffuse interstellar bands (DIBs). We have examined the wavel-C H 3 2 length ranges in question using data from our ongoing DIB survey at the Apache Point Observatory. We find that the strongest DIB (l6993) is not an acceptable wavelength match to the origin band of , based on l-C H 3 2 high-resolution laboratory data. The nondetection of interstellar features corresponding to the and K p 2 R 1 branches of para also argues against the assignment of l6993 to the branch of K p 0 R 1 l-C H K p 1 R 0 3 2 ortho . Two of the three DIBs that have been attributed to vibronic bands do not correlate in intensity l-C H 3 2 with l6993, providing further evidence against the assignment of this set of DIBs to . l-C H 3 2 Subject headings: ISM: molecules — line: identification — methods: laboratory — molecular data
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