current search for cosmic-ray anti-nucleons and conclude.

Dark Matter Production of Antihelium {#sec:production}
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We consider a fermionic Majorana dark matter candidate of mass $m_{\chi}$ annihilating into the colored or color-neutral final states $b\bar{b}$ and $W^+W^-$ through a generic, spin-0, $s$-channel resonance. In the absence of an analytic description of atomic nuclei formation, we employ the coalescence model as a simple, single-parameter phenomenological approach to describe the formation of light elements from the distributions of protons and neutrons in high energy collisions [@coal1; @coal2]. In the antideuteron case, the coalescence model assumes that nucleons with a relative invariant four-momenta $(k_n-k_p)^2=(\Delta \vec{k})^2 - (\Delta E)^2$ less than a coalescence momentum $p_0$, will bind together and form a nucleus.

Early computations of the resulting antideuteron spectrum employed a fully factorized coalescence prescription in which the $\bar{p}$ and $\bar{n}$ momentum distributions were assumed to be uncorrelated and isotropic. However, as demonstrated in Ref. [@kadastik], angular correlations introduced by jet structure play a crucial role in the formation of anti-nuclei, especially for heavy dark matter masses where the parton showers become increasingly focused. Following more recent studies, we abandon the isotropic model and instead use the `PYTHIA 8.156` [@pythia6; @pythia8] event generator to simulate 