Evaluation of the effective solid angle of a hemispherical deflector analyser with injection lens for metastable Auger projectile states

Emmanouil P. Benis, S. Doukas, Theo J. M. Zouros, Paul Indelicato, F. Parente, C. Martins, J. P. Santos, J. P. Marques

Research output: Contribution to journalArticlepeer-review

5 Citations (Scopus)

Abstract

The accurate determination of the electron yield of a metastable projectile Auger state necessitates the careful evaluation of the corresponding effective solid angle, i.e. the geometrical solid angle convoluted with the decay time of the metastable state. Recently, we presented (Doukas et. al., 2015) SIMION Monte Carlo type simulations of the effective solid angle for long lived projectile Auger states (lifetime tau similar to 10(-9)-10(-5) s) recorded by a hemispherical spectrograph with injection lens and position sensitive detector in the direction of the projectile ion. These results are important for the accurate evaluation of the 1s2s2p P-4/P-2 ratio of K-Auger cross sections whose observed non-statistical production by electron capture into He-like ions, recently a field of interesting interpretations, awaits final resolution. Here we expand and systematize our investigation using the same techniques to expose universal behaviors of the effective solid angle covering life times of 1s2s2p P-4 states for all first row ions. Our results are also compared to purely geometrical calculations of the solid angle that omit the lensing effects and serve as a benchmark for a deeper insight into the effect. (C) 2015 Elsevier B.V. All rights reserved.

Original languageEnglish
Pages (from-to)457-461
Number of pages5
JournalNuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms
Volume365
DOIs
Publication statusPublished - 15 Dec 2015

Keywords

  • Hemispherical deflection analyzer
  • Effective solid angle
  • Metastable states
  • SIMION
  • ELECTRON-ELECTRON INTERACTION
  • K-SHELL IONIZATION
  • 1S2S2P P-4 STATES
  • TRANSITION ENERGIES
  • HE TARGETS
  • 2-D PSD
  • COLLISIONS
  • IONS
  • RESOLUTION
  • H-2

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