Structure of RIPL discrete level library files
R. Capote and M. Verpelli (23-02-2023)
The description of how the files are generated can be found in INDC-NDS(0702) and in INDC-NDS(0626).
In this release,
The FORTRAN format of the GAMMA record has one additional digit for the energy
((39x,i4,1x,f10.4,3(1x,e10.3)))
SYMB A Z Nol Nog Nmax Nc Sn[MeV] Sp[MeV] 22Mg 22 12 17 18 9 4 19.382000 5.497000 The corresponding FORTRAN format is (a5,6i5,2f12.6) SYMB : mass number with symbol of the element A : mass number Z : atomic number Nol : number of levels in the decay scheme Nog : number of gamma rays in the decay scheme Nmax : maximum number of levels up to which the level scheme is complete Nc : number of a level up to which spins and parities are unique Sn : neutron separation energy in MeV Sp : proton separation energy in MeV
N1 Elv[MeV] s p T1/2 Ng J unc spins nd m percent mode m percent mode /.../ shift band 1 0.000000 0.0 1 3.86E+00 0 0+ 2 = 8.2000E+01 %IT = 1.8000E+01 %B- /.../ 0.031100 2 2 1.246300 2.0 1 2.10E12 1 2+ 0 (i3,1x,f10.6,1x,f5.1,i3,1x,(e10.3),i3,1x,a1,1x,a4,1x,a18,i3,10(1x,a2,1x,e10.4,1x,a7),f10.6,1x,3(2i)) Nl : sequential number of a level Elv : energy of the level in MeV s : level spin (unique). Whenever possible unknown spins up to Umax were inferred. Unknown and undetermined spins are entered as -1.0 p : parity (unique). If the parity of the level was unknown, positive or negative was chosen with equal probability. Parities were determined up to Umax as in the case of spins. The method of choice is not coded. The possible values are: 0 for unknown, +1 for positive and -1 for negative. T1/2 : half-life of the level (if known). All known half-lives or level widths were converted into seconds. Half-lives of stable nuclei are represented as -1.0E+0. Ng : number of gamma rays de-exciting the level. J : flag for spin estimation method (see below the list of possible flags). unc : flag for an uncertain level energy. When impossible to determine, the relative energy of the band, the energy of these band heads were set to 0.0 keV or, if the level order is known, to the preceding level energy with a note that an unknown energy X should be added. The notation uses X+, Y+, Z+ etc. for different bands. spins : original spins from the ENSDF file. nd : number of decay modes of the level (if known). Values from 0 through 10 are possible; 0 means that the level may decay via gamma-emission, and other decay modes are not known. m : decay percentage modifier; informs a user about major uncertainties. The modifiers are copied out of ENSDF with no modification, and can have the following values: =, <, >, ? (unknown, but expected), AP (approximate), GE (greater or equal), LE (less or equal), LT (less then), SY (value from systematics). percent: percentage decay of different decay modes. As a general rule the various decay modes add up 100%. There are, however, two exceptions: (i) when a small percentage decay is present, the sum may be slightly more then 100% due to rounding error, (ii) when beta -decay is followed by a heavier particle emission, the percentage of the beta-delayed particle emission is given as a portion of the beta-decay and the sum can be substantially larger then 100%. Naturally, when the modifier is "?" the sum is indefinite. mode : short indication of decay modes of a level (see Table below). shift : value assigned to the unknown "X", in MeV. band : integer assigned to band(s) to which the level is part
Nf Eg[MeV] Pg Pe ICC 3 0.055 2.790E-01 2.870E-01 5.130E-03 1 0.113 5.330E-01 5.330E-01 0.000E+00 The corresponding FORTRAN format is (39x,i4,1x,f10.4,3(1x,e10.3)) Nf : sequential number of the final state Eg : gamma-ray energy in MeV Pg : Probability that the level decays through photon (gamma ray) emission. If no branching ratio is given in the ENSDF file, Pg=0. Pe : Probability of the electromagnetic transition (photon, conversion electron, pair creation). The sum of the Pe gives the IT (electromagnetic transition) branching ratio of the level. This is 1 unless other decay modes are listed in the level record (see example below). ICC : Internal conversion coefficient of the transition.Pe, Pg, and ICC are in the following relation:
N1 Elv[MeV] s p T1/2 Ng J unc spins nd m percent mode m percent mode 2 0.643400 4.0 1 2.200E-03 1 (4+) 2 = 8.2000E+01 %IT = 1.8000E+01 %B-
Treatment of the unknown "+X" energies
The internal conversion factor are calculated using BRICC
In the FORTRAN format of the LEVEL record, the half-life format is e10.3 and the decay branching is e10.4.
The two new fields at the end - in red here below
(i3,1x,f10.6,1x,f5.1,i3,1x,(e10.3),,i3,1x,a1,1x,a4,1x,a18,i3,10(1x,a2,1x,e10.4,1x,a7),f10.6,1x,3(2i))
have the following content: