Ref HAL: hal-00640514_v1
Ref Arxiv: 1108.1128
DOI: 10.1016/J.NUCLPHYSB.2011.09.020
Ref. & Cit.: NASA ADS
Exporter : BibTex | endNote
26 citations
Abstract:

The CoGeNT experiment, dedicated to direct detection of dark matter, has recently released excess events that could be interpreted as elastic collisions of ˜10 GeV dark matter particles, which might simultaneously explain the still mysterious DAMA/LIBRA modulation signals, while in conflict with results from other experiments such as CDMS, XENON-100 and SIMPLE. It was shown that 5-15 GeV singlino-like dark matter candidates arising in singlet extensions of minimal supersymmetric scenarios can fit these data; annihilation then mostly proceeds into light singlet-dominated Higgs (pseudo-)scalar fields. We develop an effective Lagrangian approach to confront these models with the existing data on cosmic-ray antiprotons, including the latest PAMELA data. Focusing on a parameter space consistent with the CoGeNT region, we show that the predicted antiproton flux is generically in tension with the data whenever the produced (pseudo-)scalars can decay into quarks energetic enough to produce antiprotons, provided the annihilation S-wave is significant at freeze out in the early universe. In this regime, a bound on the singlino annihilation cross section is obtained, <σv>≲10‑26 cm3/s, assuming a dynamically constrained halo density profile with a local value of ρ=0.4 GeV/cm3. Finally, we provide indications on how PAMELA or AMS-02 could further constrain or detect those configurations producing antiprotons which are not yet excluded.