is not observed and the primary injection spectra must be artificially broken to compensate. This leads to an overestimate of the primary p and He flux by a factor $\sim$2 [@moskalenko2001_2]. As we are concerned with light & low energy nuclei, and no consensus on re-acceleration has been reached for this regime, we proceed without incorporating any re-acceleration mechanism. This results in a primary spectrum within 20% of measurements at low energies [@moskalenko2001_2].

The second phase of propagation is through the heliosphere and is computed using the Force Field Approximation of Gleeson & Axford [@forcefield]. The flux at the top of the atmosphere is given by $$\begin{aligned}
\label{eq:solar}
\Phi^{\text{TOA}}_{\text{A,Z}} (T_{\text{TOA}}) = \left( \frac{2 m_A A~ T_{\text{TOA}} + A^2~ T_{\text{TOA}}^2}{2 m_A A~T_{\text{IS}} + A^2~ T_{\text{IS}}^2} \right)\Phi^{\text{IS}}_{A,Z}(T_{\text{IS}}),\end{aligned}$$ where $m_A$ is the nucleus’ mass, $T_{\text{IS}}$ is the kinetic energy per nucleon at the boundary of the solar system, $T_{\text{TOA}}$ is kinetic energy per nucleon at the top of Earth’s atmosphere, and $T_{\text{IS}}=T_{\text{TOA}} + (e\phi_F |Z|/A)$. The Fisk potential $\phi_F$ describes the strength of the solar modulation and varies over an 11 year cycle. Here we take $\phi_F=500$ MV corresponding to the most optimistic detection scenario. The ratio of the [$^3\overline{\text{He}}~$]{}to [$\overline{\text{D}}~$]{}case is shown 