222RN    226RA A DECAY (1603 Y)        2017MA22,1963BA62,1971LO1923NDS    202310
222RN  H TYP=FUL$AUT=Balraj Singh, M.S. Basunia, Jun Chen et al.,$
222RN2 H CIT=NDS 192, 315 (2023)$CUT=25-Sep-2023$
222RN c  Dataset by Balraj Singh, S. Basunia, and IAEA-ICTP workshop
222RN2c  participants: S. Basu and S.S. Nayak.
222RN c  2017Ma22: precise measurements of |a emission probabilities for the
222RN2c  main branches from |a decay of {+226}Ra. Independent measurements were
222RN3c  carried out at Joint Research Centre (JRC) in Geel, and Centro de
222RN4c  Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT)
222RN5c  in Madrid, and different spectral analysis and deconvolution techniques
222RN5c  were used. Third measurement was also carried out at Laboratoire
222RN6c  National Henri Becquerel (LNHB) in Saclay, but results from this
222RN7c  experiment were not used in the final recommended values due to
222RN8c  inherent problems with the counting and analysis methods. The {+226}Ra
222RN9c  source was about 20-50 Bq strength, electrodeposited as an active 2 cm
222RNAc  diameter onto stainless steel disks of 2.5 cm diameter and 1 mm
222RNBc  thickness. The detector system was a set of two PIPS detectors and a
222RNCc  magnet system to deflect away the conversion electrons. FWHM=20 keV for
222RNDc  |a-particle spectrum.
222RN c  2018Ma11: measured absolute I|g(186) and Rn x rays from |a decay of
222RN2c  {+226}Ra using HPGe detectors and standard Czech Metrology Institute
222RN3c  (CMI) sources.
222RN c  1989Po03: measured |a|g(|q)
222RN c  1974Or02, 1970Or02: measured |a|g(|q,H)
222RN c  1971Lo19: measured E|g, I|g, |g|g-coin
222RN c  1968Bi08: measured ({+226}Ra |a)({+222}Rn |a)(|q); deduced isotropic
222RN2c  angular correlation.
222RN c  1960Be25: measured half-life of 186 level by |a|g(t)
222RN c  1960St20, 1956Ha71: measured E|g, I|g
222RN c  1954Ro06, 1954Mi53: measured |a|g(|q)
222RN c  1942Ka01: measured E|b, I|b.
222RN c  Measurements of decay constants in search of variation of decay
222RN2c  constant of {+222}Rn using {+226}Ra|){+222}Rn decay in equilibrium:
222RN d  2020Em02: measured |a spectrum from {+226}Ra decay.
222RN c  2018St04: measured decay constant of {+222}Rn using
222RN2c  {+226}Ra|){+222}Rn decay in equilibrium at the Geological Survey of
222RN3c  Israel. Authors claimed effect of solar and cosmic neutrinos on the
222RN4c  half-life of {+222}Rn based on their measurements.
222RN c  2019Po13, 2018Po01, 2016Po08, 2016Sc08: measurement of decay constant
222RN2c  of {+222}Rn from {+226}Ra|){+222}Rn decay in equilibrium at JRC-Geel
222RN3c  and PTB-Braunschweig using ionization chambers, gamma-ray spectrometers
222RN4c  and an alpha spectrometer, did not confirm any variations in the decay
222RN5c  constant from extra-terrestrial sources such as solar and cosmic
222RN6c  neutrinos proposed by 2018St04, rather the reported variations were
222RN7c  ascribed to terrestrial sources on the experimental apparatus such as
222RN8c  from solar irradiance, rainfall and weather conditions.
222RN c  2018Be08: measurement of decay constant of {+222}Rn from
222RN2c  {+226}Ra|){+222}Rn decay in equilibrium at Gran-Sasso underground
222RN3c  laboratory using |g-ray spectroscopic techniques did not show any
222RN4c  significant variations in the decay constant.
222RN c  2017Sc08, and V. Milian-Sanchez et al, Nucl. Instr. & Meth. A828, 210
222RN2c  (2010): measurement of decay constant of {+222}Rn from
222RN3c  {+226}Ra|){+222}Rn decay in equilibrium; ascribed observed
222RN4c  variation in decay constant to correlations with space weather.
222RN c  2012Th04: measurement of decay constant of {+222}Rn from
222RN2c  {+226}Ra|){+222}Rn decay in equilibrium as a function of temperature
222RN3c  of the source material using |g-ray spectroscopic techniques, and
222RN4c  reported apparent variation in activity with temperature.
222RN d  1996De19, 1992De44, 1987Be43, 1986Ch36, 1977Ba70: theory: calculated
222RN2d  |a-decay widths.
222RN d  2023Xi06, 2009Ni06, 2009De32, 2007Pe30, 2006Xu04, 2005Sh42: theory:
222RN2d  calculated |a-decay half-life
222RN cA E$From 1963Ba62, except where otherwise noted. Other
222RN2cA measurements: 1958Wa16, 1953Ba29, 1949Ro08. 1991Ry01 evaluation
222RN3cA recommended E|a values for 4784.34|a and 4601|a
222RN cA IA$Recommended values in 2017Ma22, based on results from |a spectra
222RN2cA obtained for five measurements at JRC and four at CIEMAT. Uncertainty
222RN3cA budget is explained in detail. The results are compared with those
222RN4cA in the Decay Data Evaluation Project (DDEP) (see 2008BeZV: Monographie
222RN5cA BIPM-5, Vol.4., Bureau International des Poids et Mesures or
222RN6cA consult Saclay's www.nucleide.org/DDEP.htm webpage). Note that
222RN7cA recommended values from CIEMAT are from an extrapolation procedure
222RN8cA as described in text and Fig. 7 of the paper. Exceptions are noted.
222RN9cA Other measurements: 2001La14, 1963Ba62.
222RN cA HF$HF(4784|a)=1.0 gives r{-0}({+222}Rn)=1.5397 {I3}.
222RN cG $Measured absolute x-ray emission probabilities (per 100 decays)
222RN2cG (2018Ma11): I(K|a{-2})=0.180 {I2}, I(K|a{-1})=0.299 {I3},
222RN3cG I(K|b{-1})=0.105 {I1}, I(K|b{-2})=0.033 {I1}.
222RN cG $Measured ratios of x-ray emissions (2007Ya02):
222RN2cG K{-|a2}/K{-|a1}=0.5837 {I21}, K{-|b1}/K{-|a1}=0.2165 {I33},
222RN3cG K{-|b}/K{-|a}=0.2606 {I12}.
222RN cG $Measured absolute x-ray emission probabilities (per 100 decays)
222RN2cG (2002De03,2004Mo07): I(K|a{-2})=0.159 {I40}, I(K|a{-1})=0.219 {I33},
222RN3cG I(K|b{-1})=0.080 {I6}, I(K|b{-2})=0.020 {I4}.
222RN cG $Measured absolute x-ray emission probabilities (per 100 decays)
222RN2cG (1983Sc13): I(K|a{-2})+I(K|a{-1})=0.418 {I21}, I(K|b)=0.145 {I9}
222RN cG E$From 1971Lo19, except when noted otherwise.
222RN cL E$From least-squares fit to E|g data
222RN cL J,T$From the Adopted Levels
226RA  P 0.0          0+               1603 Y    8              4870.70   25
226RA cP T$unweighted average of 1599 y {I7} (1966Ra13, uncertainty for 3|s),
226RA2cP 1577 y {I9} (1959Go80,1958Go75), 1602 y {I8} (1959Ma12), 1617 y {I12}
226RA3cP (1956Se10), 1622 y {I13} (1949Ko01). Weighted average is 1599 y {I3},
226RA4cP but with reduced |h{+2}=2.87, somewhat larger than critical |h{+2}=2.37
226RA5cP at 95% confidence level.
226RA cP QP$From 2021Wa16
222RN  N 1.0          1.0      1.0
222RN PN                                                                     3
222RN  L 0.0          0+               3.8222 D  9
222RN  A 4784.34   25 94.07  1  1.0
222RN cA E$from 1971Gr17. The original energy has been decreased by
222RN2cA 0.16 keV, as recommended by 1991Ry01. Other measurements:
222RN3cA 1996Wi27, 4781 {I1} (1963Ba62)
222RN cA IA$from 2017Ma22, measured I|a=94.077 {I10} at JRC-Geel (weighted
222RN2cA average of 94.078 {I20}, 94.077 {I30}, 94.075 {I35}, 94.080 {I10},
222RN3cA 94.064 {I25}); and 94.06 {I2} at CIEMAT (extrapolated value of
222RN4cA 94.08 {I2}, 94.12 {I2}, 94.21 {I2}, 94.29 {I2}). Value measured at
222RN5cA LNHB was: 94.49 {I4}. Other measurements: 93.84 {I11} (2001La14),
222RN6cA 94.45 (1963Ba62). Other: 94.02 {I7} from 100-(|g transition
222RN7cA intensities feeding the g.s.)
222RN  L 186.206   13 2+                 0.32 NS 2
222RN  A 4601      1  5.93   1  0.857   6
222RN cA E$the original energy of 4598 {I1} in 1963Ba62 has been increased by
222RN2cA 3 keV, as recommended by 1991Ry01, because of a change in the
222RN3cA calibration energy. E|a=4601.7 {I2} was recommended by 1983Co22 and
222RN4cA 1987El01 from measurement of 1958Wa16. E|a=4601.43 {I26} from
222RN5cA E|a(g.s.)=4784.34 {I25} and E(level).
222RN cA IA$from 2017Ma22, measured I|a=5.917 {I10} at JRC-Geel (weighted
222RN2cA average of 5.917 {I20}, 5.917 {I30}, 5.918 {I35}, 5.914 {I10},
222RN3cA 5.925 {I25}); and 5.94 {I2} at CIEMAT (extrapolated value of 5.92 {I2},
222RN4cA 5.90 {I2}, 5.81 {I2}, 5.75 {I2}). Value measured at LNHB was:
222RN5cA 5.51 {I4}. Other measurements: 6.16 {I3} (2001La14), 5.55 (1963Ba62).
222RN6cA Other: 5.97 {I7} from |g transition intensity balance
222RN  G 186.211   13 3.565  29  E2                    0.677   9
222RNS G  KC=0.1901 27$LC=0.360 5$MC=0.0963 13
222RNS G  NC=0.02509 35$OC=0.00510 7$PC=0.000584 8
222RN cG E$from 1993Di09 and 1977Zo01. Other measured energies:
222RN2cG 186.0 {I1} (1969Li10), 185.97 {I5} (1971Lo19), 186.196 {I12}
222RN3cG (1974AlZT), 185.8 {I2} (1975Ha31), 186.19 {I10} (1976De48), 186.19
222RN4cG {I16} (1982Ak03). Earlier measurements: 1951Co15, 1960St20, 1964Ew04.
222RN cG RI$weighted average of measured absolute intensity (per 100 decays)
222RN2cG of 3.555 {I29} by 2018Ma11 (note that authors quote uncertainty of
222RN3cG 0.027 in their Table 3); 3.64 {I4} (2001La14); 3.59 {I6} (1991Li11),
222RN4cG 3.50 {I5} (1983Ol01); 3.51 {I6} (1983Sc13). Other: 3.29 {I3} (1983Co22)
222RN5cG appears discrepant, although this value agrees with 3.28 {I3} from
222RN6cG intensity balance at the 186-keV level.
222RN cG $Other values: I|g(186|g)/I|g(609|g of {+214}Bi in equilibrium)=
222RN2cG 0.07812 {I31} (2002De03), 0.0785 {I5} (2002MoZP), 0.076 {I8}
222RN3cG (2000Sa32), 0.0858 {I5} (1993Di09), 0.0823 {I3} (1983Bu14), 0.092 {I10}
222RN4cG (1982Ak03), 0.0907 {I14} (1982Fa10), 0.076 {I4} (1981We18),
222RN5cG 0.0900 {I11} (1977Zo01), 0.087 {I15} (1975Ha31), 0.0820 {I12}
222RN6cG (1970Mo28), 0.079 {I8} (1964Ew04). I|g(609|g of {+214}Bi in
222RN7cG equilibrium)=45.45% {I19} is adopted in {+214}Bi |b{+-} decay dataset
222RN8cG in the ENSDF database (May 2021 update). Other I|g measurements:
222RN9cG 2002MoZP, 1990MoZP, 1976De48, 1974AlZT, 1969Li10, 1969Wa27, 1969Gr33,
222RNAcG 1967Ma51.
222RN cG M$from ce ratios measured by 1963Go21, 1955Ju14, 1954Ro05.
222RN2cG 1973De50 |a(K)=0.200 {I9}, |a(L)=0.380 {I20} were deduced by 1973De50
222RN3cG from I(K| x ray)/I(186|g), I(L| x ray)/I(186|g).
222RN  L 448.48    5  4+                52.5 PS  +44-23
222RN cL J$spin from |a(262|g)(|q) (1989Po03), with rejection of J=0, 1, 2 and 3
222RN  A 4340      1  0.0059 15 10.3   5
222RN cA IA$from 2017Ma22 (measurements carried out at JRC-Geel, CIEMAT, and
222RN2cA LNHB; authors recommend I|a=0.0059 {I15} as mean of I|a=0.0067 {I20}
222RN3cA from JRC-Geel, and 0.0052 {I15} from CIEMAT). Individual measurements
222RN4cA listed by 2017Ma22 are: 0.005 {I2}, 0.006 {I1}, 0.0102 {I25} at
222RN5cA JRC-Geel; 0.0046 {I15}, 0.0037 {I12} at CIEMAT; and 0.007 {I6} at
222RN6cA LNHB). Evaluators obtain weighted average of 0.0053 {I12} from all the
222RN7cA measured values above, except that from LNHB. Other measurement:
222RN8cA 0.0065 {I3} (1963Ba62). Precise value from 1963Ba62 is not used as
222RN9cA various summing effects, as discussed by 2017Ma22, were probably not
222RNAcA considered, implying that uncertainty of 0.0003 in 1963Ba62 may be
222RNBcA underestimated. Other: 0.0060 {I6} from |g transition intensity balance
222RN  G 262.27    5  0.0050 5    [E2]                 0.2093 29
222RNS G  KC=0.0923 13$LC=0.0868 12$MC=0.02294 32
222RNS G  NC=0.00597 8$OC=0.001225 17$PC=0.0001446 20
222RN cG RI$from I|g(262|g)/I|g(186|g)=0.0014 {I2} (1993Di09,1971Lo19). Other
222RN2cG measured ratios: 0.0029 (1960St20), 0.0025 (1956Ha71).
222RN3cG I(262|g)=0.0049 {I13} from I(4340|a)=0.0059 {I15} and |a(262|g)=0.209;
222RN4cG if I(|g+ce) of 187.1|g from the 635 level is negligible
222RN  L 600.73    4  1-                0.7 PS   +11-5
222RN cL J$spin from |a(415|g)(|q) and |a(601|g)(|q) (1989Po03), with
222RN2cL rejection of J=2 and 3
222RN  A 4191      2  0.0010 1  4.4    5
222RN cA E$4194.4 {I3} from level energy and E|a (to g.s.).
222RN cA IA$from 1963Ba62. Other: 0.00072 from |g transition intensities.
222RN  G 414.60    5 0.00030    [E1]                   0.0162823
222RNS G  KC=0.01329 19$LC=0.002278 32$MC=0.000537 8
222RNS G  NC=0.0001390 19$OC=2.99E-5 4$PC=4.19E-6 6
222RN cG RI$from I|g(414.6|g)/I|g(186|g)=0.000086 (1971Lo19). Other measured
222RN2cG ratio: 0.00021 (1960St20).
222RN  G 600.66    5 0.00049    [E1]                   0.0076211
222RNS G  KC=0.00627 9$LC=0.001034 14$MC=0.0002428 34
222RNS G  NC=6.29E-5 9$OC=1.362E-5 19$PC=1.936E-6 27
222RN cG RI$from I|g(600|g)/I|g(186|g)=0.00014 (1971Lo19). Other measured
222RN2cG ratio: 0.00033 (1960St20).
222RN  L 635.57    8  3-                0.4 NS   AP
222RN cL J$spin from |a(449|g)(|q) (1989Po03), with
222RN2cL rejection of J=0, 1, 2 and 4
222RN  A 4160      2 0.00027 5  8.6    16
222RN cA IA$from 1963Ba62. Other: 0.00027 from |g transition intensities.
222RN  G 34.81     16 6E-8   AP  [E2]                  1.30E3 4  0.00008  AP   S
222RN cG E$transition was not observed; its energy is from the level
222RN2cG scheme.
222RN cG $I(|g+ce) from intensity balance at the 635.5 level, assuming
222RN2cG negligible I(|g+ce) for the 187.1 transition
222RN  G 187.10    20            [E1]                  0.1011 14               S
222RNS G  KC=0.0809 12$LC=0.01535 22$MC=0.00365 5
222RNS G  NC=0.000941 13$OC=0.0001996 28$PC=2.67E-5 4
222RN cG E$transition was not observed; its energy is from the level
222RN2cG scheme.
222RN cG $I(|g+ce)(34.8|g)+I(|g+ce)(187.1|g)=0.00008 from the intensity balance
222RN2cG at the 635.5-keV level. Intensity balance at the 448.4-keV level,
222RN3cG without the assumption of 187.1|g feeding the 448.4 level is
222RN4cG -0.0001 {I16}, suggesting negligible intensity of 187.1 transition
222RN  G 449.37    10 0.00019   [E1]                   0.0137319
222RNS G  KC=0.01123 16$LC=0.001908 27$MC=0.000449 6
222RNS G  NC=0.0001163 16$OC=2.509E-5 35$PC=3.53E-6 5
222RN cG RI$from I|g(449|g)/I|g(186|g)=5.5|*10{+-5} (1971Lo19). Other measured
222RN2cG ratio: 9|*10{+-5} (1960St20).