The abundances of polyacetylenes toward CRL618

  title={The abundances of polyacetylenes toward CRL618},
  author={J. P. Fonfr'ia and Jos{\'e} Cernicharo and Matthew J. Richter and John H. Lacy},
  journal={The Astrophysical Journal},
We present a mid-infrared high spectral resolution spectrum of CRL618 in the frequency ranges 778 − 784 and 1227 − 1249 cm −1 (8.01 − 8.15 and 12.75 − 12.85 µm) taken with the Texas Echeloncross-Echelle Spectrograph (TEXES) and the Infrared Telescope Facility (IRTF). We have identified more than 170 ro-vibrational lines arising from C2H2, HCN, C4H2, and C6H2. We have found no unmistakable trace of C8H2. The line profiles display a complex structure suggesting the presence of polyacetylenes in… Expand

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