Previous abstract
Next abstract
Session FP - Poster Session III.
POSTER session, Friday afternoon, May 17
Atrium, Chemistry Building
Spectra of proton irradiated helium gas have been observed with a 2 cm^-1 resolution FTIR spectrometer in the region between 7200-12500 cm^-1, at a gas temperature of 4.2 K and pressures between 50-750 Torr. Textbook examples of the d\,^3\Sigma _u^+(v =0)\rightarrow c\,^3\Sigma _g^+(v =0) and D\,^1\Sigma _u^+(v =0)\rightarrow C\,^1\Sigma _g^+(v =0) transitions in He_2 were observed. Spectra taken at high pressures exhibited broadening and blue shifts of 2-4 cm^-1 on average. The c\,^3\Sigma _g^+\rightarrow a\,^3\Sigma _u^+ and C\,^1\Sigma _g^+\rightarrow A\,^1\Sigma _u^+ bands were also observed; their rotational structure being strikingly different from the d\,^3\Sigma _u^+\rightarrow c\,^3\Sigma _g^+ and D\,^1\Sigma _u^+\rightarrow C\,^1\Sigma _g^+ transitions. Liquid helium spectra at 2.6 K and between 130-750 Torr were also taken with the FTIR, in the same spectral region. Rotational lines at 130 Torr do not appear to be pressure shifted, while all rotational structure above 300 Torr disappears.
