| Geant4 Cross Reference |
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2 The photo-evaporation database contains nuclea 2 The photo-evaporation database contains nuclear deexcitation data starting
3 from a given nuclear level including informati << 3 from a given nuclear level. Each file contains data for a given isotope,
4 angular moment of a transition in a directory
<< 4 identified by Z and A.
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5
6 correlated_gamma of this dataset
<< 6 The database must first be downloaded from
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8 ********************************************** <<
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10 A file is divided into sublock, each represent <<
11 All levels included the ground state are liste <<
12 Each sublock level start by a line defining th <<
13 Followed by lines defining the gamma transitio <<
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<<
15 The line defining an energy level of the isoto <<
16 1) An integer defining the order index of the <<
17
<<
18 2) A string defining floating level (-,+X,+Y <<
19 - string means that it is a non floating le <<
20
<<
21 3) Excitation energy of the level (keV)
<<
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23 4) Level half-life (s). A -1 half-life means a <<
24
<<
25 5) JPi information of the level. The sign give <<
26 missing in the the ENSDF files.
<<
27
<<
28 6) n_gammas= Number of possible gammas deexcit <<
29 n_gammas=O means that no gamma deexcitatio <<
30
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31 After the line defining a level, a serie of n_ << 8 http://geant4.web.cern.ch/geant4/support/download.shtml
32 n_gammas gamma deexcitation.The information co <<
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34 1) The order number of the daughter level.
<< 10 and stored in a local directory. The environment variable
35
<< 11 G4LEVELGAMMADATA must then be set to point to this directory.
36 2) The energy of the gamma transition.
<< 12
>> 13 **************************************************
37
14
38 3) The relative gamma emission intensity.
<< 15 Each line describes a de-excitation *step* from a given energy level to a lower
>> 16 one (which might be the ground state). It contains data for gamma de-excitation
>> 17 and internal conversion. Notice that if multiple de-excitation
>> 18 channels are allowed for the starting energy level, these channels will be
>> 19 described in more lines (all having the same starting level).
>> 20
>> 21
>> 22 Each line contains 17 columns:
>> 23
>> 24 1) Energy of the starting nuclear level (keV)
>> 25 As mentioned before, it is possible to have more lines describing the same
>> 26 starting level, in the case where multiple de-excitation schemes are
>> 27 allowed.
>> 28
>> 29 2) Energy of the transition (keV)
>> 30 This is the energy difference between the initial and the final level.
>> 31
>> 32 3) Gamma transition probability (Ig in %)
>> 33 Note1: if the probability is less than minProbability = 1e-8%, it is forced
>> 34 to be 1e-8%.
>> 35 Note2: see column 7 how total branching ratio is computed.
>> 36
>> 37 4) Polarity
>> 38 Spin-parity variation in the transition
>> 39 [never used in real simulation]
>> 40
>> 41 5) Level half-life (s)
>> 42
>> 43 6) Angular Momentum
>> 44 Spin of the initial level
>> 45 [never used in real simulation]
39
46
40 4) The multipolarity number with 1,2,3,4,5,6,7 << 47 7) Total internal conversion coefficient : alpha = Ic/Ig
41 and 100*Nx+Ny representing multipolarity t <<
42 referring to E1,M1,E2,M2,E3,M3,.. For exa <<
43
<<
44
<<
45 5) The multipolarity mixing ratio. O means tha <<
46 or the multipolarity mixing ratio is not gi <<
47
<<
48 6) Total internal conversion coefficient : alp <<
49 Note1: total transition is the sum of gamma 48 Note1: total transition is the sum of gamma de-excitation and internal
50 conversion. Therefore total branchin 49 conversion. Therefore total branching ratio is proportional to
51 (1+alpha)*Ig
<< 50 (1+alpha)*Ig
52 Note2: total branching ratios from a given 51 Note2: total branching ratios from a given level do not always sum up to
53 100%. They are re-normalized interna << 52 100%. They are re-normalized internally.
54 Note3: relative probabilities for gamma de- 53 Note3: relative probabilities for gamma de-excitation and internal conversion
55 are 1/(1+alpha) and alpha/(1+alpha) 54 are 1/(1+alpha) and alpha/(1+alpha) respectively
56 7-16) Given only if total internal conversion << 55
57 Partial conversion probabilities for
<< 56 8-17) Partial conversion probabilities for
58 K-shell
<< 57 K-shell
59 L1-3 shells
<< 58 L1-3 shells
60 M1-5 shells
<< 59 M1-5 shells
61 Outer shells (shellID = 9 is u << 60 Outer shells (shellID = 9 is used, when applicable)
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<< 61
>> 62 Note: if the nuclear excitation energy does not match any of the known levels,
>> 63 the *nearest* level is always considered. In G4RadioactiveDecay,
>> 64 metastable states are treated correctly if the excitation energy is
>> 65 within 2.0 keV of the values in $G4RADIOACTIVEDATA.
>> 66
>> 67 For instance: take file $G4LEVELGAMMADATA/z28.a60 (Ni-60)
>> 68 Co-60 radioactive decay populates the 1332.5080-keV level of
>> 69 Ni-60 (0.12%) or the 2505.7480-keV level of Ni-60 (99.88%).
>> 70
>> 71 Deexcitation from the 2505.7480-keV level is described in lines
>> 72 6-8 of $G4LEVELGAMMADATA/z28.a60 (Ni-60)
>> 73 Here, internal conversion coefficients are negligeable (column 7)
>> 74 Therefore the nucleus will release
>> 75 1) 347 keV with 7.6e-3% probability, ending up in the 2158-keV level
>> 76 (following de-excitation hence takes place, lines 2-4 of the file)
>> 77 2) 1173 keV with 100% probability, ending up in the 1332-keV
>> 78 excited state (following de-excitation hence takes place, line 1)
>> 79 3) 2505 keV with 2e-6% probability ending up in the ground state.
>> 80
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