10.6084/m9.figshare.1012461.v1
R Guichard
M Richter
J-M Rost
U Saalmann
A A Sorokin
K Tiedtke
Ion TOF spectra of Ne taken at the photon energy of 93.0 eV and the peak intensity of (a) 4 <b>×</b> 10<sup>15</sup> W cm<sup>−2</sup> and (b) 2 <b>×</b> 10<sup>13</sup> W cm<sup>−2</sup>
2013
IOP Publishing
cm
model
photon energies
Photon energy
ion charge states
rate equations
30. Abstract
neon atoms
TOF regime
photoionization channels
ev
peak intensity
photoionization yields
ion intensities
intensity distribution
sequential photoionization
flash
laser beam
ionization yields
2013-08-13 00:00:00
article
https://iop.figshare.com/articles/_Ion_TOF_spectra_of_Ne_taken_at_the_photon_energy_of_93_0_eV_and_the_peak_intensity_of_a_4_b_b_10_su/1012461
<p><strong>Figure 2.</strong> Ion TOF spectra of Ne taken at the photon energy of 93.0 eV and the peak intensity of (a) 4 <b>×</b> 10<sup>15</sup> W cm<sup>−2</sup> and (b) 2 <b>×</b> 10<sup>13</sup> W cm<sup>−2</sup>. In the TOF regime below 2.6 μs, the ion intensities were multiplied by a factor of 30.</p> <p><strong>Abstract</strong></p> <p>At the free-electron laser FLASH, multiple ionization of neon atoms was quantitatively investigated at photon energies of 93.0 and 90.5 eV. For ion charge states up to 6+, we compare the respective absolute photoionization yields with results from a minimal model and an elaborate description including standard sequential and direct photoionization channels. Both approaches are based on rate equations and take into account a Gaussian spatial intensity distribution of the laser beam. From the comparison we conclude that photoionization up to a charge of 5+ can be described by the minimal model which we interpret as sequential photoionization assisted by electron shake-up processes. For higher charges, the experimental ionization yields systematically exceed the elaborate rate-based prediction.</p>