The asymmetry parameter β for fluorescence photons emitted during the radiative decay of the sp2,n+(1Po), sp2,n−(1Po), 2pnd(1Po) and 2pnd(3Do) series of helium doubly excited states, formed by the absorption of linearly polarized synchrotron radiation, has been measured. The results are compared with recent theoretical calculations ( ˇ Zitnik et al 2002 Phys. Rev. A 65 032520). At high n the β parameter is shown to increase and oscillate due to the excitation of triplet states, optically accessible from the helium ground state due to spin– orbit effects.
Angular distribution of the fluorescence of helium doubly photo- excited states converging on the He+(N = 2) ionization threshold / Lambourne, J. G.; Penent, F.; Lablanquie, P.; Hall, R. I.; Ahmad, M.; Zitnik, M.; Bucar, K.; Hammond, P.; Stranges, Stefano; Richter, R.; Alagia, M.; AND CORENO, M.. - In: JOURNAL OF PHYSICS. B, ATOMIC MOLECULAR AND OPTICAL PHYSICS. - ISSN 0953-4075. - STAMPA. - 36:(2003), pp. 4351-4359. [10.1088/0953-4075/36/21/013]
Angular distribution of the fluorescence of helium doubly photo- excited states converging on the He+(N = 2) ionization threshold
STRANGES, Stefano;
2003
Abstract
The asymmetry parameter β for fluorescence photons emitted during the radiative decay of the sp2,n+(1Po), sp2,n−(1Po), 2pnd(1Po) and 2pnd(3Do) series of helium doubly excited states, formed by the absorption of linearly polarized synchrotron radiation, has been measured. The results are compared with recent theoretical calculations ( ˇ Zitnik et al 2002 Phys. Rev. A 65 032520). At high n the β parameter is shown to increase and oscillate due to the excitation of triplet states, optically accessible from the helium ground state due to spin– orbit effects.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
