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Observation of Photoion Backward Emission in Photoionization of He and N2

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 نشر من قبل Sven Grundmann
 تاريخ النشر 2020
  مجال البحث فيزياء
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We experimentally investigate the effects of the linear photon momentum on the momentum distributions of photoions and photoelectrons generated in one-photon ionization in an energy range of 300 eV $leq~E_gamma~leq$ 40 keV. Our results show that for each ionization event the photon momentum is imparted onto the photoion, which is essentially the systems center of mass. Nevertheless, the mean value of the ion momentum distribution along the light propagation direction is backward-directed by $-3/5$ times the photon momentum. These results experimentally confirm a 90 year old prediction.



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