AMS-02 antiprotons, at last! Secondary astrophysical component and immediate implications for Dark Matter

Abstract

Using the updated proton and helium fluxes just released by the Ams-02 experiment we reevaluate the secondary astrophysical antiproton to proton ratio and its uncertainties, and compare it with the ratio preliminarly reported by Ams-02. We find no unambiguous evidence for a significant excess with respect to expectations. Yet, some preference for a flatter energy dependence of the diffusion coefficient (with respect to the Med benchmark often used in the literature) starts to emerge. Also, we provide a first assessment of the room left for exotic components such as Galactic Dark Matter annihilation or decay, deriving new stringent constraints. *

Measurement of Antiproton Production in p−He Collisions at sNN=110 Aaij1, Beteta2, Adeva3 et al. 2018Phys. Rev. Lett.611600View full textAdd to dashboardCite

“…Antiproton production in spallation of cosmic rays in the interstellar medium, which is mainly composed of hydrogen and helium, is expected to produce ap=p flux ratio of Oð10 −4 Þ. The observed excess ofp yields over current predictions for the known production sources [8][9][10][11] can still be accommodated within the current uncertainties. In the 10-100 GeVp energy range, these uncertainties are dominated by the limited knowledge of thep production cross section in the relevant processes.…”

On Ultra-High-Energy Cosmic Rays and Their Resultant Gamma-Rays

“…Di Mauro et al (2015) assumed that DM decay produces a + -e e flux that contributes to the AMS-02 experiment data (Accardo et al 2014;Aguilar et al 2014aAguilar et al , 2014b. A more strict lower limit on the DM lifetime was obtained by Giesen et al (2015) by fitting the AMS-02 data of anti-proton to proton ratio. The lower limit that was obtained (for DM of the same parametes as we used in this work) by Giesen et al (2015) is τ∼1.3×10 27 s. In this work we obtained somewhat stricter lower limits on the DM lifetimes, especially in the fits that included blazars (Figure 12).…”

“…A more strict lower limit on the DM lifetime was obtained by Giesen et al (2015) by fitting the AMS-02 data of anti-proton to proton ratio. The lower limit that was obtained (for DM of the same parametes as we used in this work) by Giesen et al (2015) is τ∼1.3×10 27 s. In this work we obtained somewhat stricter lower limits on the DM lifetimes, especially in the fits that included blazars (Figure 12). In Figure 13 we show the lower limits on the DM lifetimes for the + -W W channel obtained by Di Mauro et al (2015) and Giesen et al (2015), and the range of limfetimes possible for the different models in this work.…”

Dark matter from a vector field in the fundamental representation ofSU(2)L

“…In Fig. 5 we take into account upper limits data from gamma-ray experiments such as HESS [58] and Fermi-Lat [59], antiprotons measurements made by AMS-02 [60], and constraints from temperature anisotropies of the CMB by Planck satellite [61]. In the low mass region where M V 1 ≈ M W , AMS-02 and Fermi-Lat experiments are the most sensitive to the annihilation cross section predicted by the model.…”