Hanle Effect for Lifetime Determinations in the Soft X-Ray Regime

verfasst von

Moto Togawa, Jan Richter, Chintan Shah, Marc Botz, Joshua Nenninger, Jonas Danisch, Joschka Goes, Steffen Kühn, Pedro Amaro, Awad Mohamed, Yuki Amano, Stefano Orlando, Roberta Totani, Monica De Simone, Stephan Fritzsche, Thomas Pfeifer, Marcello Coreno, Andrey Surzhykov, José R.Crespo López-Urrutia

Abstract

By exciting a series of 1s2 S01→1snpP11 transitions in heliumlike nitrogen ions with linearly polarized monochromatic soft x rays at the Elettra facility, we found a change in the angular distribution of the fluorescence sensitive to the principal quantum number n. In particular it is observed that the ratio of emission in directions parallel and perpendicular to the polarization of incident radiation increases with higher n. We find this n dependence to be a manifestation of the Hanle effect, which served as a practical tool for lifetime determinations of optical transitions since its discovery in 1924. In contrast to traditional Hanle effect experiments, in which one varies the magnetic field and considers a particular excited state, we demonstrate a "soft x-ray Hanle effect"which arises in a static magnetic field but for a series of excited states. By comparing experimental data with theoretical predictions, we were able to determine lifetimes ranging from hundreds of femtoseconds to tens of picoseconds of the 1snpP11 levels, which find excellent agreement with atomic-structure calculations. We argue that dedicated soft x-ray measurements could yield lifetime data that are beyond current experimental reach and cannot yet be predicted with sufficient accuracy.

Organisationseinheit(en)

Institut für Theoretische Physik

Externe Organisation(en)

Max-Planck-Institut für Kernphysik
European X-Ray Free-Electron Laser Facility GmbH (XFEL)
Ruprecht-Karls-Universität Heidelberg
Physikalisch-Technische Bundesanstalt (PTB)
NASA Goddard Space Flight Center (NASA-GSFC)
Johns Hopkins University
Universidade Nova de Lisboa
Consiglio Nazionale delle Ricerche (CNR)
University of Camerino
Japan Aerospace Exploration Agency
Sincrotrone Trieste
CNR Istituto Officina Dei Materiali (IOM)
Helmholtz-Institut Jena
GSI Helmholtzzentrum für Schwerionenforschung GmbH
Friedrich-Schiller-Universität Jena
Technische Universität Braunschweig

Typ

Artikel

Journal

Physical review letters

Band

133

Anzahl der Seiten

7

ISSN

0031-9007

Publikationsdatum

16.10.2024

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Allgemeine Physik und Astronomie

Elektronische Version(en)

https://doi.org/10.1103/PhysRevLett.133.163202 (Zugang: Offen)