The Swan system of C-2: A global analysis of Fourier transform emission spectra

A. Tanabashi, T. Hirao, T. Amano, P. F. Bernath

Research output: Contribution to journalArticlepeer-review

Abstract

The C-2 Swan system (d(3)Pi(g)-a(3)Pi(u)) was observed in emission for the Delta v = -3 to Delta v = +2 sequences in the 14,000-24,000 cm(-1) spectral range using a Fourier transform spectrometer. We carried out a global simultaneous fit by including a wide range of vibrational states. A total of 34 bands with v' = 0-10 and v '' = 0-9 were rotationally assigned. Numerous discrepancies were found in the assignments and in the measured transition wavenumbers between the new measurements and previous results. Most of the measured transition wavenumbers and their assignments for relatively low-v bands agreed with published data. On the contrary, for high-v bands our line positions and assignments disagreed with the tabulated literature values. In particular, the lines of six bands involving the levels with v' = 4, 5, and 6 are almost completely different from the previous work. Major sources of the disagreement are thought to be line congestion and perturbations found in these bands. From the analysis, perturbations for v' = 0, 1, 2, 4, 6, 8, 9, and 10 in the d(3)Pi(g) state were identified. A study of these rotational perturbations suggest that some of them are likely caused by interactions with high-v levels of the b (3)Sigma(-)(g) state.

Original languageEnglish
Pages (from-to)472-484
Number of pages13
JournalASTROPHYSICAL JOURNAL SUPPLEMENT SERIES
Volume169
Issue number2
Publication statusPublished - Apr 2007

Keywords

  • astrochemistry
  • ISM : clouds
  • ISM : molecules
  • methods : laboratory
  • molecular data
  • stars : late-type
  • HIGH-PRESSURE BANDS
  • DIFFUSE INTERSTELLAR CLOUDS
  • SOLAR PHOTOSPHERIC SPECTRUM
  • C2 PHILLIPS SYSTEM
  • INTER-STELLAR C2
  • DIATOMIC CARBON
  • INFRARED BANDS
  • ZETA-OPHIUCHI
  • MOLECULES
  • SPECTROSCOPY

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