J/MNRAS/497/1443 Ionisation and ion fraction data (Dufresne+, 2020)
Effects of density on the oxygen ionisation equilibrium in collisional plasmas.
Dufresne R.P., Del Zanna G., Badnell N.R.
<Mon. Not. R. Astron. Soc. 497, 1443-1456 (2020)>
=2020MNRAS.497.1443D 2020MNRAS.497.1443D (SIMBAD/NED BibCode)
ADC_Keywords: Atomic physics
Keywords: atomic data - atomic processes - plasmas - Sun: transition region
Abstract:
The ion populations most frequently adopted for diagnostics in
collisional plasmas are derived from the density independent, coronal
approximation. In higher density, lower temperature conditions,
ionisation rates are enhanced once metastable levels become populated,
and recombination rates are suppressed if ions recombine into Rydberg
levels. As a result, the formation temperatures of ions shift,
altering the diagnostics of the plasma. To accurately model the effect
of ionisation from metastable levels, new electron impact, ionisation
cross sections have been calculated for oxygen, both for direct
ionisation and excitation-auto-ionisation of the ground and
metastable levels. The results have been incorporated into collisional
radiative modelling to show how the ionisation equilibrium of oxygen
changes once metastable levels become populated. Suppression of
dielectronic recombination has been estimated and also included in the
modelling, demonstrating the shifts with density in comparison to the
coronal approximation. The final results for the ionisation
equilibrium are used in differential emission measure modelling to
predict line intensities for many lines emitted by OII-VI in the
solar transition region. The predictions show improved agreement by
15-40% for OII, OVI and the inter-combination lines of OIII-V, when
compared to results from coronal approximation modelling. While there
are still discrepancies with observations of these lines, this could,
to a large part, be explained by variability in the observations.
Description:
The file levels.dat gives indices for energy levels of ions for which
data has been given. The file temprate.dat gives the temperatures at
which the rate coefficients have been calculated for each ion. The
file di_lr.dat gives the rate coefficients for direct ionisation (DI)
by electron impact resolved by initial and final levels, and the file
di_total.dat gives total DI rate coefficients from each initial level.
The file ea_lr.dat gives the rate coefficients for
excitation-auto-ionisation (EA) by electron impact resolved by
initial and final levels, and the file ea_total.dat gives total EA
rate coefficients from each initial level. Files oioneqXX.dat give the
ion populations for each ion of oxygen for temperatures given in file
tempions.dat, derived from the ionisation equilibrium at log electron
density XX (cm-3). The files are in the Chianti .ioneq file format.
Details of methods for calculations are given in the paper.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
levels.dat 56 32 Energy level indices and their configurations
temprate.dat 153 7 Temperatures for rate coefficients
di-lr.dat 175 47 Level resolved DI Rate coefficients
di-total.dat 175 32 Total DI Rate coefficients
ea-lr.dat 175 95 Level resolved EA Rate coefficients
ea-total.dat 175 23 Total EA Rate coefficients
tempions.dat 366 1 Temperatures for ion fractional populations
oioneq07.dat 616 9 Ion populations at density 1e+07 cm-3
oioneq08.dat 616 9 Ion populations at density 1e+08 cm-3
oioneq09.dat 616 9 Ion populations at density 1e+09 cm-3
oioneq10.dat 616 9 Ion populations at density 1e+10 cm-3
oioneq11.dat 616 9 Ion populations at density 1e+11 cm-3
oioneq12.dat 616 9 Ion populations at density 1e+12 cm-3
oioneq13.dat 616 9 Ion populations at density 1e+13 cm-3
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Byte-by-byte Description of file: levels.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Z Atomic number of element
6- 10 I5 --- N Number of electrons in ion
11- 15 I5 --- Level Energy level index
16- 36 A21 --- Config Electron configuration of level
37- 39 I3 --- S Spin angular momentum of level
40- 42 I3 --- L Orbital angular momentum of level
43- 45 I3 --- 2J Total angular momentum of level x2
46- 56 E11.6 eV dE FAC level energy above ground level of ion
--------------------------------------------------------------------------------
Byte-by-byte Description of file: temprate.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Z Atomic number of element
6- 10 I5 --- N Number of electrons in ion before impact
11- 21 E11.6 K Temp1 Temperature 1
22- 32 E11.6 K Temp2 Temperature 2
33- 43 E11.6 K Temp3 Temperature 3
44- 54 E11.6 K Temp4 Temperature 4
55- 65 E11.6 K Temp5 Temperature 5
66- 76 E11.6 K Temp6 Temperature 6
77- 87 E11.6 K Temp7 Temperature 7
88- 98 E11.6 K Temp8 Temperature 8
99-109 E11.6 K Temp9 Temperature 9
110-120 E11.6 K Temp10 Temperature 10
121-131 E11.6 K Temp11 Temperature 11
132-142 E11.6 K Temp12 Temperature 12
143-153 E11.6 K Temp13 Temperature 13
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Byte-by-byte Description of file: di-lr.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Z Atomic number of element
6- 10 I5 --- N Number of electrons in ion before impact
11- 15 I5 --- ilevel Initial level of ion before impact
16- 20 I5 --- flevel Final level after impact of ionised ion
21- 32 E12.3 eV IP Threshold energy for process
33- 43 E11.6 cm+3/s Rate1 Rate coefficient at Temp1
44- 54 E11.6 cm+3/s Rate2 Rate coefficient at Temp2
55- 65 E11.6 cm+3/s Rate3 Rate coefficient at Temp3
66- 76 E11.6 cm+3/s Rate4 Rate coefficient at Temp4
77- 87 E11.6 cm+3/s Rate5 Rate coefficient at Temp5
88- 98 E11.6 cm+3/s Rate6 Rate coefficient at Temp6
99-109 E11.6 cm+3/s Rate7 Rate coefficient at Temp7
110-120 E11.6 cm+3/s Rate8 Rate coefficient at Temp8
121-131 E11.6 cm+3/s Rate9 Rate coefficient at Temp9
132-142 E11.6 cm+3/s Rate10 Rate coefficient at Temp10
143-153 E11.6 cm+3/s Rate11 Rate coefficient at Temp11
154-164 E11.6 cm+3/s Rate12 Rate coefficient at Temp12
165-175 E11.6 cm+3/s Rate13 Rate coefficient at Temp13
--------------------------------------------------------------------------------
Byte-by-byte Description of file: di-total.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Z Atomic number of element
6- 10 I5 --- N Number of electrons in ion before impact
11- 15 I5 --- ilevel Initial level of ion before impact
16- 20 I5 --- flevel Final level after impact of ionised ion
21- 32 E12.3 eV IP Threshold energy for process
33- 43 E11.6 cm+3/s Rate1 Rate coefficient at Temp1
44- 54 E11.6 cm+3/s Rate2 Rate coefficient at Temp2
55- 65 E11.6 cm+3/s Rate3 Rate coefficient at Temp3
66- 76 E11.6 cm+3/s Rate4 Rate coefficient at Temp4
77- 87 E11.6 cm+3/s Rate5 Rate coefficient at Temp5
88- 98 E11.6 cm+3/s Rate6 Rate coefficient at Temp6
99-109 E11.6 cm+3/s Rate7 Rate coefficient at Temp7
110-120 E11.6 cm+3/s Rate8 Rate coefficient at Temp8
121-131 E11.6 cm+3/s Rate9 Rate coefficient at Temp9
132-142 E11.6 cm+3/s Rate10 Rate coefficient at Temp10
143-153 E11.6 cm+3/s Rate11 Rate coefficient at Temp11
154-164 E11.6 cm+3/s Rate12 Rate coefficient at Temp12
165-175 E11.6 cm+3/s Rate13 Rate coefficient at Temp13
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ea-lr.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Z Atomic number of element
6- 10 I5 --- N Number of electrons in ion
11- 15 I5 --- ilevel Initial level of ion before impact
16- 20 I5 --- flevel Final level after impact of ionised ion
21- 32 E12.3 eV IP Threshold energy for process
33- 43 E11.6 cm+3/s Rate1 Rate coefficient at Temp1
44- 54 E11.6 cm+3/s Rate2 Rate coefficient at Temp2
55- 65 E11.6 cm+3/s Rate3 Rate coefficient at Temp3
66- 76 E11.6 cm+3/s Rate4 Rate coefficient at Temp4
77- 87 E11.6 cm+3/s Rate5 Rate coefficient at Temp5
88- 98 E11.6 cm+3/s Rate6 Rate coefficient at Temp6
99-109 E11.6 cm+3/s Rate7 Rate coefficient at Temp7
110-120 E11.6 cm+3/s Rate8 Rate coefficient at Temp8
121-131 E11.6 cm+3/s Rate9 Rate coefficient at Temp9
132-142 E11.6 cm+3/s Rate10 Rate coefficient at Temp10
143-153 E11.6 cm+3/s Rate11 Rate coefficient at Temp11
154-164 E11.6 cm+3/s Rate12 Rate coefficient at Temp12
165-175 E11.6 cm+3/s Rate13 Rate coefficient at Temp13
--------------------------------------------------------------------------------
Byte-by-byte Description of file: ea-total.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 5 I5 --- Z Atomic number of element
6- 10 I5 --- N Number of electrons in ion
11- 15 I5 --- ilevel Initial level of ion before impact
16- 20 I5 --- flevel Final level after impact of ionised ion
21- 32 E12.3 eV IP Threshold energy for process
33- 43 E11.6 cm+3/s Rate1 Rate coefficient at Temp1
44- 54 E11.6 cm+3/s Rate2 Rate coefficient at Temp2
55- 65 E11.6 cm+3/s Rate3 Rate coefficient at Temp3
66- 76 E11.6 cm+3/s Rate4 Rate coefficient at Temp4
77- 87 E11.6 cm+3/s Rate5 Rate coefficient at Temp5
88- 98 E11.6 cm+3/s Rate6 Rate coefficient at Temp6
99-109 E11.6 cm+3/s Rate7 Rate coefficient at Temp7
110-120 E11.6 cm+3/s Rate8 Rate coefficient at Temp8
121-131 E11.6 cm+3/s Rate9 Rate coefficient at Temp9
132-142 E11.6 cm+3/s Rate10 Rate coefficient at Temp10
143-153 E11.6 cm+3/s Rate11 Rate coefficient at Temp11
154-164 E11.6 cm+3/s Rate12 Rate coefficient at Temp12
165-175 E11.6 cm+3/s Rate13 Rate coefficient at Temp13
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Byte-by-byte Description of file: tempions.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 6 F6.2 [K] logTemp1 Log temperature 1
7- 12 F6.2 [K] logTemp2 Log temperature 2
13- 18 F6.2 [K] logTemp3 Log temperature 3
19- 24 F6.2 [K] logTemp4 Log temperature 4
25- 30 F6.2 [K] logTemp5 Log temperature 5
31- 36 F6.2 [K] logTemp6 Log temperature 6
37- 42 F6.2 [K] logTemp7 Log temperature 7
43- 48 F6.2 [K] logTemp8 Log temperature 8
49- 54 F6.2 [K] logTemp9 Log temperature 9
55- 60 F6.2 [K] logTemp10 Log temperature 10
61- 66 F6.2 [K] logTemp11 Log temperature 11
67- 72 F6.2 [K] logTemp12 Log temperature 12
73- 78 F6.2 [K] logTemp13 Log temperature 13
79- 84 F6.2 [K] logTemp14 Log temperature 14
85- 90 F6.2 [K] logTemp15 Log temperature 15
91- 96 F6.2 [K] logTemp16 Log temperature 16
97-102 F6.2 [K] logTemp17 Log temperature 17
103-108 F6.2 [K] logTemp18 Log temperature 18
109-114 F6.2 [K] logTemp19 Log temperature 19
115-120 F6.2 [K] logTemp20 Log temperature 20
121-126 F6.2 [K] logTemp21 Log temperature 21
127-132 F6.2 [K] logTemp22 Log temperature 22
133-138 F6.2 [K] logTemp23 Log temperature 23
139-144 F6.2 [K] logTemp24 Log temperature 24
145-150 F6.2 [K] logTemp25 Log temperature 25
151-156 F6.2 [K] logTemp26 Log temperature 26
157-162 F6.2 [K] logTemp27 Log temperature 27
163-168 F6.2 [K] logTemp28 Log temperature 28
169-174 F6.2 [K] logTemp29 Log temperature 29
175-180 F6.2 [K] logTemp30 Log temperature 30
181-186 F6.2 [K] logTemp31 Log temperature 31
187-192 F6.2 [K] logTemp32 Log temperature 32
193-198 F6.2 [K] logTemp33 Log temperature 33
199-204 F6.2 [K] logTemp34 Log temperature 34
205-210 F6.2 [K] logTemp35 Log temperature 35
211-216 F6.2 [K] logTemp36 Log temperature 36
217-222 F6.2 [K] logTemp37 Log temperature 37
223-228 F6.2 [K] logTemp38 Log temperature 38
229-234 F6.2 [K] logTemp39 Log temperature 39
235-240 F6.2 [K] logTemp40 Log temperature 40
241-246 F6.2 [K] logTemp41 Log temperature 41
247-252 F6.2 [K] logTemp42 Log temperature 42
253-258 F6.2 [K] logTemp43 Log temperature 43
259-264 F6.2 [K] logTemp44 Log temperature 44
265-270 F6.2 [K] logTemp45 Log temperature 45
271-276 F6.2 [K] logTemp46 Log temperature 46
277-282 F6.2 [K] logTemp47 Log temperature 47
283-288 F6.2 [K] logTemp48 Log temperature 48
289-294 F6.2 [K] logTemp49 Log temperature 49
295-300 F6.2 [K] logTemp50 Log temperature 50
301-306 F6.2 [K] logTemp51 Log temperature 51
307-312 F6.2 [K] logTemp52 Log temperature 52
313-318 F6.2 [K] logTemp53 Log temperature 53
319-324 F6.2 [K] logTemp54 Log temperature 54
325-330 F6.2 [K] logTemp55 Log temperature 55
331-336 F6.2 [K] logTemp56 Log temperature 56
337-342 F6.2 [K] logTemp57 Log temperature 57
343-348 F6.2 [K] logTemp58 Log temperature 58
349-354 F6.2 [K] logTemp59 Log temperature 59
355-360 F6.2 [K] logTemp60 Log temperature 60
361-366 F6.2 [K] logTemp61 Log temperature 61
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Byte-by-byte Description of file: oioneq*.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Z Atomic number of element
4- 6 I3 --- N Ion number starting with neutral atom
7- 16 E10.3 --- Pop1 Ion fractional population at Temp1
17- 26 E10.3 --- Pop2 Ion fractional population at Temp2
27- 36 E10.3 --- Pop3 Ion fractional population at Temp3
37- 46 E10.3 --- Pop4 Ion fractional population at Temp4
47- 56 E10.3 --- Pop5 Ion fractional population at Temp5
57- 66 E10.3 --- Pop6 Ion fractional population at Temp6
67- 76 E10.3 --- Pop7 Ion fractional population at Temp7
77- 86 E10.3 --- Pop8 Ion fractional population at Temp8
87- 96 E10.3 --- Pop9 Ion fractional population at Temp9
97-106 E10.3 --- Pop10 Ion fractional population at Temp10
107-116 E10.3 --- Pop11 Ion fractional population at Temp11
117-126 E10.3 --- Pop12 Ion fractional population at Temp12
127-136 E10.3 --- Pop13 Ion fractional population at Temp13
137-146 E10.3 --- Pop14 Ion fractional population at Temp14
147-156 E10.3 --- Pop15 Ion fractional population at Temp15
157-166 E10.3 --- Pop16 Ion fractional population at Temp16
167-176 E10.3 --- Pop17 Ion fractional population at Temp17
177-186 E10.3 --- Pop18 Ion fractional population at Temp18
187-196 E10.3 --- Pop19 Ion fractional population at Temp19
197-206 E10.3 --- Pop20 Ion fractional population at Temp20
207-216 E10.3 --- Pop21 Ion fractional population at Temp21
217-226 E10.3 --- Pop22 Ion fractional population at Temp22
227-236 E10.3 --- Pop23 Ion fractional population at Temp23
237-246 E10.3 --- Pop24 Ion fractional population at Temp24
247-256 E10.3 --- Pop25 Ion fractional population at Temp25
257-266 E10.3 --- Pop26 Ion fractional population at Temp26
267-276 E10.3 --- Pop27 Ion fractional population at Temp27
277-286 E10.3 --- Pop28 Ion fractional population at Temp28
287-296 E10.3 --- Pop29 Ion fractional population at Temp29
297-306 E10.3 --- Pop30 Ion fractional population at Temp30
307-316 E10.3 --- Pop31 Ion fractional population at Temp31
317-326 E10.3 --- Pop32 Ion fractional population at Temp32
327-336 E10.3 --- Pop33 Ion fractional population at Temp33
337-346 E10.3 --- Pop34 Ion fractional population at Temp34
347-356 E10.3 --- Pop35 Ion fractional population at Temp35
357-366 E10.3 --- Pop36 Ion fractional population at Temp36
367-376 E10.3 --- Pop37 Ion fractional population at Temp37
377-386 E10.3 --- Pop38 Ion fractional population at Temp38
387-396 E10.3 --- Pop39 Ion fractional population at Temp39
397-406 E10.3 --- Pop40 Ion fractional population at Temp40
407-416 E10.3 --- Pop41 Ion fractional population at Temp41
417-426 E10.3 --- Pop42 Ion fractional population at Temp42
427-436 E10.3 --- Pop43 Ion fractional population at Temp43
437-446 E10.3 --- Pop44 Ion fractional population at Temp44
447-456 E10.3 --- Pop45 Ion fractional population at Temp45
457-466 E10.3 --- Pop46 Ion fractional population at Temp46
467-476 E10.3 --- Pop47 Ion fractional population at Temp47
477-486 E10.3 --- Pop48 Ion fractional population at Temp48
487-496 E10.3 --- Pop49 Ion fractional population at Temp49
497-506 E10.3 --- Pop50 Ion fractional population at Temp50
507-516 E10.3 --- Pop51 Ion fractional population at Temp51
517-526 E10.3 --- Pop52 Ion fractional population at Temp52
527-536 E10.3 --- Pop53 Ion fractional population at Temp53
537-546 E10.3 --- Pop54 Ion fractional population at Temp54
547-556 E10.3 --- Pop55 Ion fractional population at Temp55
557-566 E10.3 --- Pop56 Ion fractional population at Temp56
567-576 E10.3 --- Pop57 Ion fractional population at Temp57
577-586 E10.3 --- Pop58 Ion fractional population at Temp58
587-596 E10.3 --- Pop59 Ion fractional population at Temp59
597-606 E10.3 --- Pop60 Ion fractional population at Temp60
607-616 E10.3 --- Pop61 Ion fractional population at Temp61
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Acknowledgements:
Roger Dufresne, rpd21(at)cam.ac.uk
Giulio Del Zanna, gd232(at)cam.ac.uk
Nigel Badnell, badnell(at)phys.strath.ac.uk
(End) Roger Dufresne [Univ. of Cambridge], Patricia Vannier [CDS] 30-Jun-2020