Weakly Interacting Massive Particles (WIMPs) are the candidates of dark matter in our universe. Up to now any direct interaction of WIMP with nuclei has not been observed yet. The exclusion limits of the spin-independent cross section of WIMP-nucleon which have been experimentally obtained is about 10 −7 pb at high mass region and only 10 −5 pb at low mass region. China Jin-Ping underground laboratory CJPL is the deepest underground lab in the world and provides a very promising environment for direct observation of dark matter. The China Dark Matter Experiment (CDEX) experiment is going to directly detect the WIMP flux with high sensitivity in the low mass region. Both CJPL and CDEX have achieved a remarkable progress in recent two years. The CDEX employs a point-contact germanium semi-conductor detector PCGe whose detection threshold is less than 300 eV. We report the measurement results of Muon flux, monitoring of radioactivity and Radon concentration carried out in CJPL, as well describe the structure and performance of the 1 kg PCGe detector CDEX-1 and 10kg detector array CDEX-10 including the detectors, electronics, shielding and cooling systems. Finally we discuss the physics goals of the CDEX-1, CDEX-10 and the future CDEX-1T detectors.

Abstract:We study LHC Higgs signatures from the extended electroweak gauge symmetry SU(2) ⊗ SU(2)⊗U(1). Under this gauge structure, we present an effective UV completion of the 3-site moose model with ideal fermion delocalization, which contains two neutral Higgs states (h, H) plus three new gauge bosons (W ′ , Z ′ ). We study the unitarity, and reveal that the exact E 2 cancellation in the longitudinal V L V L scattering amplitudes is achieved by the joint role of exchanging both spin-1 new gauge bosons and spin-0 Higgs bosons. We identify the lighter Higgs state h with mass 125 GeV, and derive the unitarity bound on the mass of heavier Higgs boson H . The parameter space of this model is highly predictive. We study the production and decay signals of this 125 GeV Higgs boson h at the LHC. We demonstrate that the h Higgs boson can naturally have enhanced signals in the diphoton channel gg → h → γγ , while the event rates in the reactions gg → h → W W * and gg → h → ZZ * are generally suppressed relative to the SM expectation. Searching the h Higgs boson via the associated production and the vector boson fusions are also discussed for our model. We further analyze the LHC signals of the heavier Higgs boson H as a new physics discriminator from the SM. For wide mass-ranges of H , we derive constraints from the existing LHC searches, and study the discovery potential of H at the LHC (8 TeV) and LHC (14 TeV).

We explain the recent diphoton excesses around 750 GeV by both ATLAS and CMS as a singlet scalar Φ which couples to SM gluon and neutral gauge bosons only through higher dimensional operators. A natural explanation is that Φ is a pseudo-Nambu-Goldstone boson (pNGB) which receives parity violation through anomaly if there exists a hidden strong dynamics. The singlet and other light pNGBs will decay into two SM gauge bosons and even serves as the meta-stable coloured states which can be probed in the future. By accurately measuring their relative decay and the total production rate in the future, we will learn the underlying strong dynamics parameter. The lightest baryon in this confining theory could serve as a viable dark matter candidate.

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