IEEEX_16_742_2009_corona_Li_Bonifaci_Haeften_Atrazhev.pdf (552.06 kB)
Luminescence from Liquid Helium Excited by Corona Discharges
journal contribution
posted on 2009-08-11, 13:25 authored by Z.-L. Li, N. Bonifaci, F. Aitken, A. Denat, Klaus von Haeften, V. M. Atrazhev, V. A. ShakhatovLiquid helium (LHe) at 4.2 K was electronically excited using a corona discharge for
both negative and positive high voltages. The experiments were carried out for
different pressures in the range from 0.1 to 10 MPa at constant temperature. The light
emitted from the zone close to the tip was spectroscopically analyzed showing features
from atoms and excimer helium. The shifts and widths of the observed lines and bands
were found to depend on the applied hydrostatic pressure and on the tip polarity. Our
analysis showed that classic pressure broadening theory cannot account for the
observed widths and shifts rather than the presence of bubbles which surround single
excited atoms and molecules. For positive tip polarities red shifted features distinct
from pure He and He2* were observed and tentatively assigned to “red satellites”.