Speaker
Description
Hydrocarbon ions play an important role in combustion and plasma processes, and in the chemistry of planetary atmospheres and the interstellar medium. Laboratory spectroscopic studies of these essential reaction intermediates give valuable insights on their geometrical and electronic structure, and provide accurate transition frequencies needed for their identification in space. Conventional absorption spectroscopy has in the past been successfully applied for spectroscopic studies of molecular ions, but is often hampered by low number densities and spectral congestion due to the multitude of species produced at high excitation energies during their formation process. These limitations can be overcome by performing experiments on mass-selected ions in cryogenic ion trap instruments.
Here I will present first laboratory data on the gas phase spectra of several astrophysically important hydrocarbon cations ranging in size from comparatively small systems (e.g., C$_2$H$^+$, C$_3$H$_2^+$, and C$_3$H$^+$) to PAH cations, made possible by our recent development of sensitive methods for vibrational and rotational action spectroscopy in cryogenic ion traps [1-4]. Details of broadband infrared experiments using the unique combination of a cryogenic ion trap instrument interfaced to the free electron lasers at the FELIX Laboratory, as well as of complementary high-resolution studies using narrow-band continuous-wave radiation sources will be given.
[1] S. Brünken, L. Kluge, A. Stoffels, O. Asvany, and S. Schlemmer, Astrophys. J. Lett., 783, L4 (2014).
[2] O. Asvany, S. Brünken, L. Kluge, and S. Schlemmer, Appl. Phys. B, 114, 203 (2014).
[3] O. Asvany, K.M.T. Yamada, S Brünken, A. Potapov, and S. Schlemmer, Science, 347, 1346 (2015).
[4] S. Brünken, L. Kluge, A. Stoffels, J. Pèrez-Rios, and S. Schlemmer, J. Mol. Spectrosc., 332, 67 (2017).
