Nearly a century after Einstein first predicted the existence of gravitational waves, a global network of Earth-based gravitational wave observatories [1, 2, 3, 4] is seeking to directly detect this faint radiation using precision laser interferometry. Photon shot noise, due to the quantum nature of light, imposes a fundamental limit on the attometre-level sensitivity of the kilometre-scale Michelson interferometers deployed for this task. Here, we inject squeezed states to improve the performance of one of the detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) beyond the quantum noise limit, most notably in the frequency region down to 150 Hz, critically important for several astrophysical sources, with no deterioration of performance observed at any frequency. With the injection of squeezed states, this LIGO detector demonstrated the best broadband sensitivity to gravitational waves ever achieved, with important implications for observing the gravitational-wave Universe with unprecedented sensitivity

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The results of recent testing of a prototype detector to search for weakly interacting massive particles in the galactic halo are presented. The detector is an optically imaged, low pressure time projection chamber. This technique offers significant advantages for the detection of dark matter in that it measures both the energy and direction of the nuclear recoil. Using neutron and xray sources we also demonstrate that this detector has substantial electron background rejection capability (greater than 99.8%) and can utilize various target nuclei, such as hydrogen and argon.PACS numbers: 95.55. Vj, 29.40.Cs, 95.35.+d One of the most compelling questions of modern physics is the existence and nature of dark matter (DM) in the Universe. There is considerable observational evidence [1] that as much as 90% of the matter in the cosmos does not interact electromagnetically and betrays its existence only through gravitational effects. Spiral galaxy rotation curves imply a DM component which is present on galactic scales. One popular model explaining the flatness of galactic rotation curves postulates the existence of a self-gravitating, isothermal, spherical distribution of weakly interacting massive particles (WIMPs). The distribution of particles is assumed to be nonrotating and is supported against gravitational collapse by the random thermal velocities of the particles. The canonical models assume a simple Maxwellian velocity distribution (8~3 00 km/s) with a cutoff at the galactic escape velocity.Extensions to the standard model provide many particle DM possibilities with supersymmetry (SUSY) contributing one of the most promising candidates, the neutralino (g). The mass and couplings of the g depend upon several parameters in the theory, but once specified, cross sections for interaction with ordinary matter [2] can be calculated. Typical cross sections for elastic scattering on nuclei are g~10 38 10 cm and masses range from 1 to 1000 GeV.The Earth's motion through the galactic halo can provide distinctive signatures for WIMP detection. The average velocity of the Earth through the halo is the circular velocity vo = 220 km/s of the Sun around the galactic center. Simple two-body kinematics with terrestial nuclei give maximum recoil energies in the keV region. Assuming knowledge of the local mass density of WIMPs in the halo ( 0.3 GeV/cms), it is possible to estimate [3] the interaction rates of weak elastic scattering to be 0.01 -1000 events/(kg day), depending upon WIMP mass, o, and the detector used.In the past several years there have been a number of experiments and proposals [4] for detecting WIMPs. Most direct searches rely upon the elastic scattering of WIMPs with ordinary matter producing a recoiling nu-dA dE dcosp -[vo cosyv; ] V2 halowhere v;"=(m~+ m ) E/2m~m is the minimum WIMP velocity that can produce a nuclear recoil of energy E, and vh & --3v&/2. The expression above shows that the nuclear recoil direction has a strong angular dependence, which can be exploited to distinguish between signal (WIM...

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Cities are now home to more than 50% of the world’s population and emit large quantities of pollutants from sources such as fossil fuel combustion and the leakage of refrigerants. We demonstrate the utility of persistent synoptic longwave hyperspectral imaging to study the ongoing leakage of refrigerant gases in New York City, compounds that either deplete the stratosphere ozone or have significant global warming potential. In contrast to current monitoring programs that are based on country-level reporting or aggregate measures of emissions, we present the identification of gaseous plumes with high spatial and temporal granularity in real-time over the skyline of Manhattan. The reported data highlights the emission of chemicals scheduled for phase-out. Our goal is to contribute to better understanding of the composition, sources, concentration, prevalence and patterns of emissions for the purposes of both research and policy.