Details

Autor(en) / Beteiligte

• Kircher, M
• Rist, J
• Trinter, F
• Grundmann, S
• Waitz, M
• Melzer, N
• Vela-Pérez, I
• Mletzko, T
• Pier, A
• Strenger, N
• Siebert, J
• Janssen, R
• Schmidt, L Ph H
• Artemyev, A N
• Schöffler, M S
• Jahnke, T
• Dörner, R
• Demekhin, Ph V

Titel

Recoil-Induced Asymmetry of Nondipole Molecular Frame Photoelectron Angular Distributions in the Hard X-ray Regime

Ist Teil von

• Physical review letters, 2019-12, Vol.123 (24), p.243201-243201, Article 243201

Ort / Verlag

United States: American Physical Society

Erscheinungsjahr

2019

Quelle

American Physical Society Journals

Beschreibungen/Notizen

• We investigate angular emission distributions of the 1s photoelectrons of N_{2} ionized by linearly polarized synchrotron radiation at hν=40  keV. As expected, nondipole contributions cause a very strong forward-backward asymmetry in the measured emission distributions. In addition, we observe an unexpected asymmetry with respect to the polarization direction, which depends on the direction of the molecular fragmentation. In particular, photoelectrons are predominantly emitted in the direction of the forward nitrogen atom. This observation cannot be explained via asymmetries introduced by the initial bound and final continuum electronic states of the oriented molecule. The present simulations assign this asymmetry to a novel nontrivial effect of the recoil imposed to the nuclei by the fast photoelectrons and high-energy photons, which results in a propensity for the ions to break up along the axis of the recoil momentum. The results are of particular importance for the interpretation of future experiments at x-ray free electron lasers operating in the few tens of keV regime, where such nondipole and recoil effects will be essential.