Recent results of the searches for Supersymmetry in final states with one or two leptons at CMS are presented. Many Supersymmetry scenarios, including the Constrained Minimal Supersymmetric extension of the Standard Model (CMSSM), predict a substantial amount of events containing leptons, while the largest fraction of Standard Model background events -which are QCD interactions -gets strongly reduced by requiring isolated leptons. The analyzed data was taken in 2011 and corresponds to an integrated luminosity of approximately L = 1 fb −1 . The center-of-mass energy of the pp collisions was √ s = 7 TeV.

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LUX-ZEPLIN (LZ) is a next-generation dark matter direct detection experiment that will operate 4850 feet underground at the Sanford Underground Research Facility (SURF) in Lead, South Dakota, USA. Using a two-phase xenon detector with an active mass of 7 tonnes, LZ will search primarily for low-energy interactions with weakly interacting massive particles (WIMPs), which are hypothesized to make up the dark matter in our galactic halo. In this paper, the projected WIMP sensitivity of LZ is presented based on the latest background estimates and simulations of the detector. For a 1000 live day run using a 5.6-tonne fiducial mass, LZ is projected to exclude at 90% confidence level spin-independent WIMP-nucleon cross sections above 1.4 × 10 −48 cm 2 for a 40 GeV=c 2 mass WIMP. Additionally, a 5σ discovery potential is projected, reaching cross sections below the exclusion limits of recent experiments. For spin-dependent WIMP-neutron(-proton) scattering, a sensitivity of 2.3 × 10 −43 cm 2 (7.1 × 10 −42 cm 2) for a 40 GeV=c 2 mass WIMP is expected. With underground installation well underway, LZ is on track for commissioning at SURF in 2020.

We report the first measurements of the absolute ionization yield of nuclear recoils in liquid xenon, as a function of energy and electric-field. Independent experiments were carried out with two dualphase time projection chamber prototypes, developed for the XENON Dark Matter project. We find that the charge yield increases with decreasing recoil energy, and exhibits only a weak field dependence. These results are a first demonstration of the capability of dual phase xenon detectors to discriminate between electron and nuclear recoils, a key requirement for a sensitive dark matter search at recoil energies down to 20 keV. Introduction: Current evidence indicates that one quarter of the mass-energy density of the universe is composed of cold, non-baryonic dark matter, which has thus far been observed only through its gravitational interactions with normal matter. Its precise nature is undetermined, but weakly interacting massive particles (WIMPs) are an attractive candidate which may be detectable via rare elastic scattering interactions depositing a few tens of keV in target nuclei. For a review of the motivation for WIMPs, and current experimental WIMP searches, see [1]. The best limits, from CDMS, are <0.06 events/kg/day (in Ge) [2]. Improving the search sensitivity will require both larger detectors and lower radioactive backgrounds. An attractive method to achieve this uses liquid noble gas-based detectors, which promise to be readily scalable to the multi-ton scale. For the XENON experiment [3], we are developing a large volume liquid xenon (LXe) dual-phase time-projection-chamber (TPC) that features simultaneous measurement of recoil ionization and scintillation to determine the energy and 3-D localization on an event-by-event basis. Nuclear recoils from WIMPs (and neutrons) have denser tracks, and thus have been assumed to have greater electron-ion recombination than electron recoils, providing a basis for discrimination against radioactive background gammas and betas. However, ionization from these nuclear recoils has not been measured until now. In this report, we describe the first measurements of the ionization yield of low energy nuclear recoils in LXe and confirm the baseline discrimination capability of this technique.

We outline the experimental concept and key scientific capabilities of AION (Atom Interferometer Observatory and Network), a proposed experimental programme using cold strontium atoms to search for ultra-light dark matter, to explore gravitational waves in the mid-frequency range between the peak sensitivities of the LISA and LIGO/Virgo/ KAGRA/INDIGO/Einstein Telescope/Cosmic Explorer experiments, and to probe other frontiers in fundamental physics. AION would complement other planned searches for dark matter, as well as probe mergers involving intermediate-mass black holes and explore early-universe cosmology. AION would share many technical features with the MAGIS experimental programme, and synergies would flow from operating AION in a network with this experiment, as well as with other atom interferometer experiments such as MIGA, ZAIGA and ELGAR. Operating AION in a network with other gravitational wave detectors such as LIGO, Virgo and LISA would also offer many synergies.