PPPC 4 DM ID: A Poor Particle Physicist Cookbook for Dark Matter Indirect Detection

TL;DR

PPPC4DMID provides a comprehensive, model-independent toolkit for Dark Matter indirect detection Signals across charged cosmic rays, prompt and secondary gamma rays, and extragalactic gamma rays. It combines high-statistics DM production spectra (via Pythia/Herwig), robust Galaxy-wide propagation through halo functions, and region-specific observables with J- and B-factors, delivering ready-to-use numerical outputs and interpolation functions. The work explicitly quantifies uncertainties from Monte Carlo generators and propagation, and offers practical recipes to obtain Earth fluxes for e±, p̄, ̄d, γ, and ν across a wide DM mass range. By unifying production, propagation, and observation in a single, accessible framework, it enables rapid, cross-channel, multi-messenger DM analyses and robust interpretation of current and future experiments.

Abstract

We provide ingredients and recipes for computing signals of TeV-scale Dark Matter annihilations and decays in the Galaxy and beyond. For each DM channel, we present the energy spectra of electrons and positrons, antiprotons, antideuterons, gamma rays, neutrinos and antineutrinos e, mu, tau at production, computed by high-statistics simulations. We estimate the Monte Carlo uncertainty by comparing the results yielded by the Pythia and Herwig event generators. We then provide the propagation functions for charged particles in the Galaxy, for several DM distribution profiles and sets of propagation parameters. Propagation of electrons and positrons is performed with an improved semi-analytic method that takes into account position-dependent energy losses in the Milky Way. Using such propagation functions, we compute the energy spectra of electrons and positrons, antiprotons and antideuterons at the location of the Earth. We then present the gamma ray fluxes, both from prompt emission and from Inverse Compton scattering in the galactic halo. Finally, we provide the spectra of extragalactic gamma rays. All results are available in numerical form and ready to be consumed.

Figures (20)

• Figure 1: DM profiles and the corresponding parameters to be plugged in the functional forms of eq. (\ref{['eq:profiles']}). The dashed lines represent the smoothed functions adopted for some of the computations in Sec. \ref{['propagationapprox']}. Notice that we here provide 2 (3) decimal significant digits for the value of $r_s$ ($\rho_s$): this precision is sufficient for most computations, but more would be needed for specific cases, such as to precisely reproduce the $J$ factors (discussed in Sec.\ref{['promptgamma']}) for small angular regions around the Galactic Center.
• Figure 2: Comparison between Monte Carlo results: Pythia is the continuous line, Herwig is dashed. Photons (red), $e^\pm$ (green), $\bar{p}$ (blue), $\nu = \nu_e +\nu_\mu+\nu_\tau$ (black).
• Figure 3: Primary fluxes of $e^\pm$, $\bar{p}$, $\bar{d}$, $\gamma$ and $\nu_e$.
• Figure 4: Energy distribution between the final states particles: $e^\pm$, hadrons ($p+d$), $\gamma$ and $\nu$, for a set of characteristic annihilation channels. The inner (outer) pie refers to a DM mass of 200 GeV (5 TeV). For each pie chart, the first caption gives the energy fraction going into $\gamma$ and $e^\pm$ ($E_{\gamma+e}$) with respect to the total. The second caption gives the energy fraction into hadronic final states ($E_{p+d}$) with respect to $\gamma$ and $e^\pm$.
• Figure 5: Energy loss coefficient function for electrons and positrons in the Milky Way. Left panel: at several locations along the galactic radial coordinate $r$, right panel: above (or below) the location of the Earth along the coordinate $z$. The dot points at the value of $\tau_\odot$ (see next subsection).