http://arxiv.org/abs/1901.02281
We present the detection of fullerenes C_60 and C_70 in the interstellar gas nearby stars hosting protoplanetary disks in the few Myr old IC 348 star-forming region of the Perseus Giant Molecular Cloud. Mid-IR vibrational transitions of C_60 and C_70 in emission are reported in Spitzer IRS spectra of the interstellar material near three IC 348 stars (LRLL 1, 2 and 58). The rather low C_60 and C_70 vibrational temperatures, 200-300 K, suggest that fullerenes are attached to dust grains in the material around these very young stars. Bands of the C_60^+ and C_60^- are also tentatively identified in two of these stars from which we infer ionization fractions of 20 and 10 $\%$, respectively. If the abundances derived from the observed emission lines were representative of the abundances in the protoplanetary disks around these stars we estimate that fullerene C_60, the most abundant of the two species, could host ~ 0.1 % of the total available carbon in the existing disks. This heavily relies on estimates of the intensity of the UV radiation field nearby these stars. The accretion of fullerenes in the early phases of planet formation may have implications on the chemistry of complex organic molecules in young forming planets. Accreted fullerenes may provide a reservoir of pentagonal and hexagonal carbon rings which could be important as building blocks of prebiotic molecules.
S. Iglesias-Groth
Wed, 9 Jan 19
36/46
Comments: 5 figures, 8 pages. Submitted 18 july 2018., to MNRAS
You must be logged in to post a comment.