Cosmic-ray positrons strongly constrain leptophilic dark matter

Cosmic-ray positrons have long been considered a powerful probe of dark matter annihilation. In particular, myriad studies the unexpected rise in positron fraction debated its or pulsar origins. this paper, we instead examine potential for extremely precise measurements by AMS-02 to hard leptophilic candidates that do not spectral features similar bulk observed excess. Utilizing detailed cosmic-ray propagation model includes primary flux generated Galactic pulsars addition secondary component constrained Helium and proton measurements, produce robust fit local spectrum. We find no evidence bump correlated with matter, set strong constraints on annihilation cross-section fall below thermal masses 60 GeV 380 into $\tau^+\tau^-$ $e^+e^-$, respectively, our default model.