Determination of the $\alpha$-decay half-life of ${}^{210}\text{Po}$ based on film and slice bismuth samples at room temperature

The $\alpha$ decay rate of ${}^{210}\text{Po}$ was measured in a film sample $\left({}^{210}\text{Po}@{\mathrm{Bi}}_2{\mathrm{O}}_3\right)$ and a slice sample $\left({}^{210}\text{Po}@\mathrm{Bi}\mathrm{metal}\right)$, respectively. The former was used as a reference sample. The half-lives of ${}^{210}\text{Po}@{\mathrm{Bi}}_2{\mathrm{O}}_3$ and ${}^{210}\text{Po}@\mathrm{Bi}$ metal environments were observed to be $(138.40\pm 0.21\text{d})$ and $(138.87\pm 0.87\text{d})$ at room temperature, respectively. It was found that the half-life of ${}^{210}\text{Po}$ is consistent with international recommendations within the uncertainty limits, and we did not find any deviation of the $\alpha$ decay rate of ${}^{210}\text{Po}$ between film sample $\left({}^{210}\text{Po}@{\mathrm{Bi}}_2{\mathrm{O}}_3\right)$ and slice sample $\left({}^{210}\text{Po}@\mathrm{Bi}\mathrm{metal}\right)$.

Figure 1

$\alpha$ spectra of the film sample. The $\alpha$ energy of ${}^{210}\text{Po}$ on the surface of the sample is about 5.3 MeV. The sharp peak on the right side is from a research pulser.

Figure 2

$\alpha$ spectra of the slice sample. The maximum $\alpha$ energy of ${}^{210}\text{Po}$ in the slice target sample is 5.3 MeV. The sharp peak on the right side is from a research pulser.

Figure 3

Decay curve of ${}^{210}\text{Po}$ in the slice metal sample over about 350 d.

Figure 4

Decay curve of ${}^{210}\text{Po}$ in the film metal sample over about 700 d.

Figure 5

Plot of the two determined half-lives along with the reference value (error bars represent $1\sigma$). All two half-lives are longer than the one given in the reference.