DOI

We spectroscopically studied the population of the excited hydrogen atomic states with the principal quantum numbers n = 3 and 4 in a decaying plasma produced by a pulsed discharge in a mixture of helium (p = 40.4 Torr) with a small amount of hydrogen ([H2] ≈ 1012 cm-3). Experiments on recording the response of the spectral line intensities to a short-duration electron temperature perturbation revealed the contribution of electron-ion recombination to the population of the H*(n = 3) states in the early afterglow. The ions produced by collisions of hydrogen molecules with metastable He(23S1) atoms, whose density decreases relatively rapidly with time in the decaying plasma, were assumed to be involved in this process. No population of the H*(n = 4) atomic levels due to electron-ion recombination was found. Our experimental results are consistent with the conclusions of previous studies that excitation transfer during collisions of metastable helium molecules with hydrogen molecules plays a major role in the population of the excited hydrogen atomic states both with n = 3 and with n = 4 during most of the afterglow.

Original languageEnglish
Pages (from-to)507-510
Number of pages4
JournalOptics and Spectroscopy (English translation of Optika i Spektroskopiya)
Volume95
Issue number4
DOIs
StatePublished - Oct 2003

    Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Atomic and Molecular Physics, and Optics

ID: 92875769