Uncertainty Components Evaluated in the Determination of the Massic Activity CA (in units of MBq · g−1) for Rhenium-186 Perrhenate Solution Used in Experiment 2
| Component | Comment | % |
|---|---|---|
| LS measurement repeatability | Standard deviation in CA for 10 repeated measurements on a single LS cocktail; average for 5 independent LS cocktails. | 0.10 |
| LS cocktail variability | Standard deviation in CA for 5 independently prepared LS cocktails; average for 5 independent LS cocktails. | 0.21 |
| 186Re half-life | Standard uncertainty in half-life (0.08%) over the measurement decay interval. | 0.0043 |
| 186Re EC branching ratio | Standard uncertainty in EC branching (1.3%). | 0.08 |
| 186Re β-branching ratio | Standard uncertainty in β-branching (0.12%). | 0.10 |
| Gravimetric determinations | Standard uncertainty in mass determinations for a single LS counting source. | 0.05 |
| 186Re dilution factor | Standard uncertainty in gravimetric determination of dilution from 186Re master solution | 0.07 |
| 3H-standard decay correction | Estimated standard uncertainty of 0.46% in the decay of the 3H standard over 18.5 a to 19 a. | 0.01 |
| 3H-standard calibration | Standard uncertainty of 0.18% from NIST calibration. | 0.01 |
| 3H-standard gravimetric dilution | Estimated standard uncertainty (0.06%) for gravimetrically-determined dilution factor. | 0.01 |
| Gravimetric determination of 3H LS samples | Estimated standard uncertainty of 0.05% in the mass determination of any single 3H LS cocktail. | 0.01 |
| Spectrometer dependence | Standard deviation in CA for 5 independently-prepared LS cocktails counted in 2 spectrometers. | 0.0001 |
| Combined (uc = Σui) | 0.28 | |
| Expanded (Uc = uc · k; k = 2) | 0.56 |