We report results from the Cryogenic Dark Matter Search at the Soudan Underground Laboratory (CDMS II) featuring the full complement of 30 detectors. A blind analysis of data taken between October ...2006 and July 2007 sets an upper limit on the weakly interacting massive particle (WIMP) nucleon spin-independent cross section of 6.6x10;{-44} cm;{2} (4.6x10;{-44} cm;{2} when combined with previous CDMS II data) at the 90% confidence level for a WIMP mass of 60 GeV/c;{2}. This achieves the best sensitivity for dark matter WIMPs with masses above 44 GeV/c;{2}, and significantly restricts the parameter space for some favored supersymmetric models.
We report new results from the Cryogenic Dark Matter Search (CDMS II) at the Soudan Underground Laboratory. Two towers, each consisting of six detectors, were operated for 74.5 live days, giving ...spectrum-weighted exposures of 34 (12) kg d for the Ge (Si) targets after cuts, averaged over recoil energies 10-100 keV for a weakly interacting massive particle (WIMP) mass of 60 GeV/c2. A blind analysis was conducted, incorporating improved techniques for rejecting surface events. No WIMP signal exceeding expected backgrounds was observed. When combined with our previous results from Soudan, the 90% C.L. upper limit on the spin-independent WIMP-nucleon cross section is 1.6 x 10(-43) cm2 from Ge and 3 x 10(-42) cm2 from Si, for a WIMP mass of 60 GeV/c2. The combined limit from Ge (Si) is a factor of 2.5 (10) lower than our previous results and constrains predictions of supersymmetric models.
We report the first results from a search for weakly interacting massive particles (WIMPs) in the Cryogenic Dark Matter Search experiment at the Soudan Underground Laboratory. Four Ge and two Si ...detectors were operated for 52.6 live days, providing 19.4 kg d of Ge net exposure after cuts for recoil energies between 10 and 100 keV. A blind analysis was performed using only calibration data to define the energy threshold and selection criteria for nuclear-recoil candidates. Using the standard dark-matter halo and nuclear-physics WIMP model, these data set the world's lowest exclusion limits on the coherent WIMP-nucleon scalar cross section for all WIMP masses above 15 GeV/c2, ruling out a significant range of neutralino supersymmetric models. The minimum of this limit curve at the 90% C.L. is 4 x 10(-43) cm2 at a WIMP mass of 60 GeV/c2.
Astrophysical observations indicate that dark matter constitutes most of the mass in our universe, but its nature remains unknown. Over the past decade, the Cryogenic Dark Matter Search (CDMS II) ...experiment has provided world-leading sensitivity for the direct detection of weakly interacting massive particle (WIMP) dark matter. The final exposure of our low-temperature germanium particle detectors at the Soudan Underground Laboratory yielded two candidate events, with an expected background of 0.9 ± 0.2 events. This is not statistically significant evidence for a WIMP signal. The combined CDMS II data place the strongest constraints on the WIMP-nucleon spin-independent scattering cross section for a wide range of WIMP masses and exclude new parameter space in inelastic dark matter models.
Background Bronchiectasis is a potentially serious condition characterized by permanent and abnormal widening of the airways, the prevalence of which is not well described. We sought to describe the ...trends, associated conditions, and risk factors for bronchiectasis among adults aged ≥ 65 years. Methods A 5% sample of the Medicare outpatient claims database was analyzed for bronchiectasis trends among beneficiaries aged ≥ 65 years from 2000 to 2007. Bronchiectasis was identified using International Classification of Diseases, Ninth Revision, Clinical Modification claim diagnosis codes for acquired bronchiectasis. Period prevalence was used to describe sex- and race/ethnicity-specific rates, and annual prevalence was used to describe trends and age-specific rates. We estimated trends using Poisson regression and odds of bronchiectasis using multivariate logistic regression. Results From 2000 to 2007, 22,296 people had at least one claim for bronchiectasis. The 8-year period prevalence of bronchiectasis was 1,106 cases per 100,000 people. Bronchiectasis increased by 8.7% per year. We identified an interaction between the number of thoracic CT scans and race/ethnicity; period prevalence varied by a greater degree by number of thoracic CT scans among Asians compared with whites or blacks. Among people with one CT scan, Asians had a 2.5- and 3.9-fold higher period prevalence compared with whites and blacks. Conclusions Bronchiectasis prevalence increased significantly from 2000 to 2007 in the Medicare outpatient setting and varied by age, sex, and race/ethnicity. This increase could be due to a true increase in the condition or an increased recognition of previously undiagnosed cases.
We report results from a reanalysis of data from the Cryogenic Dark Matter Search (CDMS II) experiment at the Soudan Underground Laboratory. Data taken between October 2006 and September 2008 using ...eight germanium detectors are reanalyzed with a lowered, 2 keV recoil-energy threshold, to give increased sensitivity to interactions from weakly interacting massive particles (WIMPs) with masses below ∼10 GeV/c(2). This analysis provides stronger constraints than previous CDMS II results for WIMP masses below 9 GeV/c(2) and excludes parameter space associated with possible low-mass WIMP signals from the DAMA/LIBRA and CoGeNT experiments.
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