A controlled and precise determination of the cross sections of the fusion reactions ${}^7\mathrm{Be}$$(p,\gamma )$${}^8\mathrm{B}$ and ${}^3\mathrm{He}$(${}^4\mathrm{He}$,$\gamma$)${}^7\mathrm{Be}$, which play an important role in determining the solar neutrino flux, necessitates the knowledge of a precise value of the electron-capture half-life of ${}^7\mathrm{Be}$. This half-life may depend on the material hosting the ${}^7\mathrm{Be}$ atoms via small modifications of the electron density around the ${}^7\mathrm{Be}$ nucleus. In this brief communication we report on the measurement of ${}^7\mathrm{Be}$ implanted in four materials: copper, aluminum, sapphire, and PVC. The four results are consistent with a null host dependence within two standard deviations and their weighted average of 53.236(39) d agrees very well with the adopted value in the literature, 53.22(6) d. The present results may exhibit a slight (0.22%) increase of the half-life at room temperature for metals compared to insulators that requires further studies.

• Received 24 August 2006

DOI:https://doi.org/10.1103/PhysRevC.75.012801