Collisional quenching of metastable states of antiprotonic helium by hydrogen and deuterium molecules

B. Ketzer, T. Von Egidy, F. J. Hartmann, C. Maierl, R. Pohl, J. Eades, E. Widmann, T. Yamazaki, M. Kumakura, N. Morita, R. S. Hayano, M. Hori, T. Ishikawa, H. A. Torii, I. Sugai, D. Horváth

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

The quenching of metastable states of antiprotonic helium by collisions with hydrogen and deuterium molecules was studied. A systematic investigation of the delayed annihilation time spectra at various H2 and D2 admixture ratios at the ppm level revealed characteristic changes of their shape, which indicated a strong principal and orbital quantum number dependent quenching of levels in both cases. Applying a laser spectroscopy technique to measure the lifetimes of individual states and cascades we deduced H2 and D2 quenching cross-sections for the states (n, l) = (39,35) and (37,34). These cross-sections establish for D2 molecules the strong increase of the quenching efficiency with increasing principal quantum number n of the state under investigation previously reported for the case of H2 admixtures. Our experiments indicate that the low-n state (37,34) is somewhat less affected by D2 than by H2. while the high-n state (39, 35) is equally quenched by both isotopes.

Original languageEnglish
Pages (from-to)305-316
Number of pages12
JournalEuropean Physical Journal D
Volume13
Issue number3
DOIs
Publication statusPublished - Mar 1 2001

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Fingerprint Dive into the research topics of 'Collisional quenching of metastable states of antiprotonic helium by hydrogen and deuterium molecules'. Together they form a unique fingerprint.

  • Cite this

    Ketzer, B., Von Egidy, T., Hartmann, F. J., Maierl, C., Pohl, R., Eades, J., Widmann, E., Yamazaki, T., Kumakura, M., Morita, N., Hayano, R. S., Hori, M., Ishikawa, T., Torii, H. A., Sugai, I., & Horváth, D. (2001). Collisional quenching of metastable states of antiprotonic helium by hydrogen and deuterium molecules. European Physical Journal D, 13(3), 305-316. https://doi.org/10.1007/s100530170246