184OS 188PT A DECAY 10NDS 201002 184OS H TYP=FUL$AUT=CORAL M. BAGLIN$CIT=NDS 111,275 (2010)$CUT=1-Oct-2009$ 184OS C T1/2(188PT)=10.2 D 3, the weighted average of the measured half-lives 184OS2C of 10.3 D 4 (1954Na25), 10.0 D 3 (1955Sm42), 10.2 D 3 (1963Gr08) and 184OS3C 10.5 D 10 (1963Ka17). 184OS C 184OS C %A(188PT)=2.6E-5 3 is weighted average of 3.0E-5% 6 (1963GR08), 184OS2C 2.2E-5% 5 (1979Ha10) and 2.8E-5% 5 (1978El11). Other value: 184OS3C 5.0E-5 25 (1963Ka17). 184OS D %A=2.2E-5 5 WAS LISTED BY 1979Ha10; THEIR METHOD OF DETERMINATION 184OS2D IS NOT CLEAR. THE 188PT AND 188HG ISOTOPES WERE PRODUCED IN 184OS3D Pb(P,SPALLATION), PRODUCTS WERE MASS SEPARATED. THE AUTHORS STATE 184OS4D THAT "THE TOTAL AMOUNT OF 188HG ATOMS COLLECTED DURING THE EXPERIMENT 184OS5D BY ABSOLUTE GAMMA-COUNTING OF THE RESIDUAL ACTIVITY OF 188PT ON THE 184OS6D COLLECTOR FOIL." "BY EXTENDING THE MEASURING TIME TO SEVERAL 184OS7D DAYS, AN ALPHA-BRANCHING RATIO OF (2.2+-0.5)E-7 WAS DETERMINED, 184OS8D IN GOOD AGREEMENT WITH THE FINDINGS OF KARRAS, ET AL (1963Ka17)". 184OS9D THE %A FROM THIS REFERENCE, THEREFORE, IS NOT INCLUDED IN AVERAGE. 184OS D THE AUTHORS OF 1963Ka17 STATED THAT "BY MEASURING THE Ir-Os K X-RAY 184OS2D ACTIVITY OF THE SOURCE, THE ALPHA BRANCHING WAS FOUND TO BE 0.5E-6 184OS3D WITHIN A FACTOR OF TWO." NO GAMMA TRANSITION IN A DECAY TO 184OS 184OS4D HAS BEEN OBSERVED. NO EXPLANATION IS GIVEN BY THE AUTHORS FOR Os 184OS5D K X-RAY SOURCE. THE %A FROM THIS REFERENCE IS NOT CONSIDERED HERE 184OS6D IN ADOPTING THE ALPHA BRANCHING. 184OS C 184OS C QA(188PT)=4008 5 is recommended by 2003Au03 AND 2009AUZZ. 184OS CA HF R0(184OS)=1.464 7 is calculated by requiring 184OS2CA the hindrance factor for the 3922-KEV ALPHA to be 1.0. I(3922A)=95 5 184OS3CA (FROM IA>90%) is used in computation. 188PT P 0.0 0+ 10.2 D 3 4008 5 184OS N 2.6E-7 3 184OS L 0.0 0+ 184OS A 3919 7 95 5 1.0 184OS CA E WEIGHTED AVERAGE OF 3905 15 (1979Ha10), 184OS2CA 3915 10 (1978El11), and 3930 10 (1963Gr08). THIS EA IMPLIES 184OS3CA QA=4004 7 (cf. 4008 5 FROM 2003AU03). 184OS CA IA only one ALPHA group has been observed. Upper limit on 184OS2CA intensity of an unobserved 3804-KEV ALPHA transition to the 2+ state 184OS3CA at 119.77 KEV is calculated to be <10 per 100 A DECAYS by requiring 184OS4CA its hindrance to be greater than 1.