J/A+AS/97/443 Fluorescence for Be to Zn (Kaastra+ 1993)
X-ray emission from thin plasmas. I.
Multiple Auger ionisation and fluorescence processes for Be to Zn.
Kaastra J.S., Mewe R.
<Astron. Astrophys. Suppl. Ser. 97, 443 (1993)>
=1993A&AS...97..443K 1993A&AS...97..443K
ADC_Keywords: Atomic physics
Keywords: atomic data
Abstract:
The basic physical processes responsible for X-ray emission from thin
plasmas are considered. Collisional ionization or photoionization of
inner shells of neutral atoms and ions leads to the creation of a
vacancy in one of the inner shells of the ion or atom, which is filled
by a cascade of radiative (fluorescent) and nonradiative (Auger)
transitions. The net result is the ejection of several electrons and
photons, leaving the atom in a multiply ionized state. In this paper,
the distribution of the number of emitted photons and electrons after
the creation of a hole in an inner shell of an atom or ion is
calculated for all ions from H to Zn. The method consists of two
stages: the calculation of transition rates for a given electron
configuration, and calculation of probabilities of the several cascade
sequences using these transition rates.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2 76 1090 Electron distribution
table3 30 11732 Fluorescence yields
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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1- 2 I2 --- Z Atomic number
3- 5 I3 --- st Ionisation stage of ion BEFORE ionisation
(neutral=1 etc.)
6- 7 I2 --- s Shell number of primary vacancy
(1-7 correspond to K L1 L2 L3 M1 M2 M3)
8- 14 F7.1 eV I Ionisation energy of the primary vacancy
in eV (from Lotz)
15- 21 F7.1 eV EA Energy that goes into Auger electrons, in eV
22- 25 I4 10-3 epsilon Correction factor defined in equation 6 of
the paper
27- 31 I5 10-4 PrEj1 Probability that a photo-ionisation leads to
ejection of 1 electron (1)
32- 36 I5 10-4 PrEj2 Probability of 2 electrons photoionisation (1)
37- 41 I5 10-4 PrEj3 Probability of 2 electrons photoionisation (1)
42- 46 I5 10-4 PrEj4 Probability of 2 electrons photoionisation (1)
47- 51 I5 10-4 PrEj5 Probability of 2 electrons photoionisation (1)
52- 56 I5 10-4 PrEj6 Probability of 2 electrons photoionisation (1)
57- 61 I5 10-4 PrEj7 Probability of 2 electrons photoionisation (1)
62- 66 I5 10-4 PrEj8 Probability of 2 electrons photoionisation (1)
67- 71 I5 10-4 PrEj9 Probability of 2 electrons photoionisation (1)
72- 76 I5 10-4 PrEj10 Probability of 2 electrons photoionisation (1)
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Note (1): NOTE that the probabilities have been multiplied by 10000.
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Byte-by-byte Description of file: table3
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Bytes Format Units Label Explanations
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1- 3 I3 --- Z Atomic number
4- 6 I3 --- st Ionisation stage of ion BEFORE ionisation
(neutral=1 etc.)
7- 9 I3 --- s Shell number of primary vacancy
(1-7 correspond to K L1 L2 L3 M1 M2 M3)
10- 12 I3 --- Delta Number of Auger electrons ejected before
emission of the line; the line therefore
occurs in the ion with ionisation stage
st+Delta+1 (the factor 1 corresponds to the
photo-electron)
13- 15 I3 --- il Line identification number; labels according
to table 1 of the paper. Note that il runs
from 1 to 22.
16- 23 F8.1 eV E Approximate line energy of the transition;
note that often more accurate energies can
be found in the literature.
24- 30 F7.4 --- omega The fluorescence yield omega for this line
(number of photons emitted
per primary vacancy)
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(End) Francois Ochsenbein [CDS] 13-Apr-1993