分类: 天文学 >> 天文学 提交时间: 2023-02-19
摘要: We improve the calculations of the elastic motion induced by the dark matter hits on the surface of the mirror equipped with the interferometer for gravitational waves detection. We focus on the discovery potential of such a dark matter signal on the third-generation European gravitational waves detector, the Einstein Telescope. By taking the thickness of mirror into account, more than one resonances are predicted in the sensitive regime of high frequency interferometer. When mass of dark matter is heavier than a few PeV or is highly boosted, the signal-to-noise ratio could exceed one, and Einstein Telescope should be about to detect this dark matter signal.
分类: 物理学 >> 基本粒子与场物理学 提交时间: 2017-08-24
摘要: We explicitly show that split-universal extra dimension (split-UED), a recently suggested extension of universal extra dimension (UED) model, can nicely explain recent anomalies in cosmic-ray positrons and electrons observed by PAMELA and ATIC/PPB-BETS. Kaluza-Klein (KK) dark matters mainly annihilate into leptons because the hadronic branching fraction is highly suppressed by large KK quark masses and the antiproton flux agrees very well with the observation where no excess is found . The flux of cosmic gamma-rays from pion decay is also highly suppressed and hardly detected in low energy region (Eγ . 20 GeV). Collider signatures of colored KK particles at the LHC, especially q1q1 production, are studied in detail. Due to the large split in masses of KK quarks and other particles, hard pT jets and missing ET are generated, which make it possible to suppress the standard model background and discover the signals.
分类: 物理学 >> 基本粒子与场物理学 提交时间: 2017-08-24
摘要: Kaluza-Klein photon in universal extra dimension models is one of the most attractive dark matter candidates as a weakly interacting massive particle. Having a characteristic split spectrum in split universal extra dimension the relic density of Kaluza-Klein photon with 900GeV mass is in good agreement with the observed dark matter amount in our Universe. Interestingly KaluzaKlein photon in the same mass range also provides excellent fits to the recently observed excesses in cosmic electron and positron fluxes. The amount of gamma-ray contributions, mostly from tau decays, can be significant around 300 GeV, thus can be observed or constrained by the forthcoming Fermi-LAT diffuse gamma-ray data.