FERMILAB-CONF-07-606-E CDMS experiment : current status and future

We present the current status of the Cryogenic Dark Matter Search (CDMS). The five tower detector array, total 30 detectors, are running stable since October 2006. We have accumulated more than 900 kg-days of low background data. We also summarize the prospect of SuperCDMS project

CDMS experiment: current status and future

We present the current status of the Cryogenic Dark Matter Search (CDMS). The five tower detector array, total 30 detectors, are running stable since October 2006. We have accumulated more than 900 kg-days of low background data. We also summarize the prospect of SuperCDMS project

Results from the Cryogenic Dark Matter Search at Soudan Underground Laboratory

We present results from the Cryogenic Dark Matter Search at Soudan Underground Laboratory for two-tower arrays of detector. Twelve detectors were operated from March 25 to August 8, 2004, or 74.5 detector live days.Within expected background, no statistically significant indication of a WIMP signal was observed. Based on this null observation and combined with our previous results, we exclude a spin-averaged WIMP-nucleon interaction cross section above 1.6 x 10{sup -43} cm{sup 2} for Ge detectors, and 3 x 10{sup -42} cm{sup 2} for Si detectors, for a WIMP mass 60GeV/c{sup 2} with 90%C.L. This result constrains parameter space of minimal supersymmetric standard models (MSSM) and starts to reach the parameter space of a constrained model (CMSSM)

Extended Axion Dark Matter Search Using the CAPP18T Haloscope

We report an extended search for the axion dark matter using the CAPP18T haloscope. The CAPP18T experiment adopts innovative technologies of a high-temperature superconducting magnet and a Josephson parametric converter. The CAPP18T detector was reconstructed after an unexpected incident of the high-temperature superconducting magnet quenching. The system reconstruction includes rebuilding the magnet, improving the impedance matching in the microwave chain, and mechanically readjusting the tuning rod to the cavity for improved thermal contact. The total system noise temperature is $\sim$0.6\,K. The coupling between the cavity and the strong antenna is maintained at $\beta \simeq 2$ to enhance the axion search scanning speed. The scan frequency range is from 4.8077 to 4.8181 GHz. No significant indication of the axion dark matter signature is observed. The results set the best upper bound of the axion-photon-photon coupling ($g_{a\gamma\gamma}$) in the mass ranges of 19.883 to 19.926\,$\mu$eV at $\sim$0.7$\times|g_{a\gamma\gamma}^{\text{KSVZ}}|$ or $\sim$1.9$\times|g_{a\gamma\gamma}^{\text{DFSZ}}|$ with 90\,\% confidence level. The results demonstrate that a reliable search of the high-mass dark matter axions can be achieved beyond the benchmark models using the technology adopted in CAPP18T.Comment: 7 pages and 4 figure

Kaluza-Klein Dark Matter: Direct Detection vis-a-vis LHC

We explore the phenomenology of Kaluza-Klein (KK) dark matter in very general models with universal extra dimensions (UEDs), emphasizing the complementarity between high-energy colliders and dark matter direct detection experiments. In models with relatively small mass splittings between the dark matter candidate and the rest of the (colored) spectrum, the collider sensitivity is diminished, but direct detection rates are enhanced. UEDs provide a natural framework for such mass degeneracies. We consider both 5-dimensional and 6-dimensional non-minimal UED models, and discuss the detection prospects for various KK dark matter candidates: the KK photon $\gamma_1$, the KK $Z$-boson $Z_1$, the KK Higgs boson $H_1$ and the spinless KK photon $\gamma_H$. We combine collider limits such as electroweak precision data and expected LHC reach, with cosmological constraints from WMAP, and the sensitivity of current or planned direct detection experiments. Allowing for general mass splittings, we show that neither colliders, nor direct detection experiments by themselves can explore all of the relevant KK dark matter parameter space. Nevertheless, they probe different parameter space regions, and the combination of the two types of constraints can be quite powerful. For example, in the case of $\gamma_1$ in 5D UEDs the relevant parameter space will be almost completely covered by the combined LHC and direct detection sensitivities expected in the near future.Comment: 52 pages, 29 figure

Axion Haloscope Using an 18 T High Temperature Superconducting Magnet

We report details on the axion dark matter search experiment that uses the innovative technologies of a High-Temperature Superconducting (HTS) magnet and a Josephson Parametric Converter (JPC). An 18 T HTS solenoid magnet is developed for this experiment. The JPC is used as the first stage amplifier to achieve a near quantum-limited low-noise condition. The first dark matter axion search was performed with the 18 T axion haloscope. The scan frequency range is from 4.7789 GHz to 4.8094 GHz (30.5 MHz range). No significant signal consistent with Galactic dark matter axion is observed. Our results set the best limit of the axion-photon-photon coupling ($g_{a\gamma\gamma}$) in the axion mass range of 19.764 to 19.890 $\mu$eV. Using the Bayesian method, the upper bounds of $g_{a\gamma\gamma}$ are set at 0.98$\times|g_{a\gamma\gamma}^{\text{KSVZ}}|$ (1.11$\times|g_{a\gamma\gamma}^{\text{KSVZ}}|$) in the mass ranges of 19.764 to 19.771 $\mu$eV (19.863 to 19.890 $\mu$eV), and at 1.76 $\times|g_{a\gamma\gamma}^{\text{KSVZ}}|$ in the mass ranges of 19.772 to 19.863 $\mu$eV with 90\% confidence level, respectively. We report design, construction, operation, and data analysis of the 18 T axion haloscope experiment.Comment: PRD published versio

Transparent organic light-emitting diodes with different bi-directional emission colors using color-conversion capping layers

We report a study on transparent organic light-emitting diodes (OLEDs) with different bidirectional emission colors, enabled by color-conversion organic capping layers. Starting from a transparent blue OLED with an uncapped Ag top electrode exhibiting an average transmittance of 33.9%, a 4-(Dicyanomethylene)-2-methyl- 6-(4-dimethylaminostyryl)-4Hpyran (DCM)-doped tris-(8-hydroxy-quinolinato)-aluminium (Alq3) capping layer is applied to achieve color-conversion from blue to orange-red on the top side while maintaining almost unchanged device transmittance. This color-conversion capping layer does not only change the color of the top side emission, but also enhances the overall device efficiency due to the optical interaction of the capping layer with the primary blue transparent OLED. Top white emission from the transparent bi-directional OLED exhibits a correlated color temperature around 6,000K-7,000K, with excellent color stability as evidenced by an extremely small variation in color coordinate of ∆(x,y) = (0.002, 0.002) in the forward luminance range of 100-1000 cd m-2. At the same time, the blue emission color of bottom side is not influenced by the color conversion capping layer, which finally results in different emission colors of the two opposite sides of our transparent OLEDsPostprintPeer reviewe

T-1025 IU SciBath-768 detector tests in MI-12

This is a memorandum of understanding between the Fermi National Accelerator Laboratory (Fermilab) and the experimenters of Department of Physics and Center for Exploration of Energy and Matter, Indiana University, who have committed to participate in detector tests to be carried out during the 2012 Fermilab Neutrino program. The memorandum is intended solely for the purpose of recording expectations for budget estimates and work allocations for Fermilab, the funding agencies and the participating institutions. it reflects an arrangement that currently is satisfactory to the parties; however, it is recognized and anticipated that changing circumstances of the evolving research program will necessitate revisions. The parties agree to modify this memorandum to reflect such required adjustments. Actual contractual obligations will be set forth in separate documents. The experimenters propsoe to test their prototype 'SciBat-768' detector in the MI-12 building for 3 months (February-April) in Spring 2012. The major goal of this effort is to measure or limit the flux of beam-induced neutrons in a far-off-axis (> 45{sup o}) location of the Booster Neutrino Beamline (BNB). This flux is of interest for a proposed coherent neutral-current neutrino-argon elastic scattering experiment. A second goal is to collect more test data for the SciBath-768 to enable better understanding and calibration of the device. The SciBath-768 detector successfully ran for 3 months in the MINOS Underground Area in Fall 2011 as testbeam experiment T-1014 and is currently running above ground in the MINOS service building. For the run proposed here, the experiments are requesting: space in MI-12 in which to run the SciBath detector during February-April 2012 while the BNB is operating; technical support to help with moving the equipment on site; access to power, internet, and accelerator signals; and a small office space from which to run and monitor the experiment