The Cryogenic Dark Matter Search (CDMS) employs Ge and Si detectors to search for weakly interacting massive particles (WIMPs) via their elastic-scattering interactions with nuclei while ...discriminating against interactions of background particles. CDMS data, accounting for the neutron background, give limits on the spin-independent WIMP-nucleon elastic-scattering cross section that exclude unexplored parameter space above 10 GeV/c2 WIMP mass and, at >75% C.L., the entire 3sigma allowed region for the WIMP signal reported by the DAMA experiment.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UM
The Cryogenic Dark Matter Search (CDMS) employs massive ionization- and phonon-mediated detectors to search for WIMPs via their elastic scattering interactions with nuclei while discriminating ...against interactions by other background particles. Limits on the WIMP-nucleon scattering cross-section, based on 3.1
kg
d of exposure, exclude new parameter space in the 10–30
GeV WIMP mass region and also a portion of the region allowed by the DAMA annual modulation search (Bernabei, Phys. Lett. 450 (1999) 448).
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Studies of the relationship between luminance and pupil diameter have produced widely differing results. This research note explores the possibility that this is due, in part, to differences in the ...size of the adapting fields used by various workers. We present measurements of pupil diameter as a function of luminance for a variety of field subtenses. The results indicate a consistent trend for smaller subtenses to produce less pupil constriction. For field diameters of up to 25 degrees, replotting the data in terms of corneal flux density (i.e. the product of luminance and subtended area) causes an approximate convergence onto a single function described by D = 7.75-5.75 (F/846)0.41/((F/846)0.41 / 2) where D is the pupil diameter (mm) and F is the corneal flux density (cdm-2 deg2). This equation should be of some practical use in estimation of natural pupil diameter.
Installation and commissioning of the CDMSII experiment at Soudan Akerib, D.S; Alvaro-Dean, J; Armel, M.S ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
03/2004, Volume:
520, Issue:
1-3
Journal Article
Peer reviewed
In the past year and a half, the Cryogenic Dark Matter Search (CDMS) collaboration has been active at the Soudan mine in installing a system for running ZIP detectors that will be used to search for ...dark matter in the form of Weakly Interacting Massive Particles. Presently, there is an operating cryogenic system, working electronics, a functional data acquisition and analysis system, passive shielding, an active muon veto, and 12 ZIP detectors. Six of the 12 ZIP detectors have been tested in situ and are fully operational with acceptable noise profiles. CDMS is in the process of commissioning the experiment and expects to be making a background measurement by the end of summer 2003.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
The Cryogenic Dark Matter Search experiment uses cooled germanium and silicon detectors for a direct search for weakly interacting massive particles in our Galaxy. The novel detectors allow a high ...degree of background rejection by discriminating between electron and nuclear recoils through the simultaneous measurement of the energy deposited in phonons and ionization. Exposures on the order of one kilogram-day from initial runs of our experiment yield (preliminary) upper limits on the WIMP-nucleon cross section that are comparable to much longer runs of other experiments. Current and future runs promise significant improvement, primarily due to improved detectors and reduced surface-electron backgrounds.
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6.
Single photon imaging X-ray spectrometers Segall, K.; Wilson, C.M.; Li, L. ...
IEEE transactions on applied superconductivity,
06/1999, Volume:
9, Issue:
2
Journal Article, Conference Proceeding
Peer reviewed
We have developed superconducting, single-photon imaging X-ray detectors with an energy resolution of 26 eV FWHM at 6 keV and a spatial resolution of 0.5 /spl mu/m over an effective area of 18 /spl ...mu/m/spl times/100 /spl mu/m. The energy resolution is among the best reported for this kind of detector and is within a factor of /spl ap/4 of its theoretical limit. The calculated absorption efficiency of the detector is 28%. Scaling to larger areas and higher quantum efficiency appear possible. We discuss the device design and readout along with possible sources of resolution broadening.
Low temperature detectors for dark matter searches Cabrera, B.; Brink, P.L.; Clarke, R.M. ...
Nuclear physics. B, Proceedings supplement/Nuclear physics. B, Proceedings supplements,
11/1996, Volume:
51, Issue:
2
Journal Article
Peer reviewed
Open access
We present an overview of the low temperature detectors being developed for dark matter searches. The important background discrimination techniques are discussed. In addition, we describe recent ...advances in the athermal phonon detectors being developed by our group at Stanford.
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All records of Mandarin Ducks in the UK from 1745 to 1987 were collated and analysed. Comparisons were made between records covering this whole period and records covering the years 1970 to 1987; ...recent records do not reflect major changes in the overall range of distribution, but the species is far more widespread than previously published maps of its distribution suggest. The current British population is estimated to be at least 7000 birds, more than three times greater than previous estimates.
We have demonstrated a new type of phonon sensor for cryogenic particle detectors with high-bandwidth SQUID readout. Our Quasiparticle-trap assisted Electrothermal feedback Transition edge sensor ...(QET) utilizes aluminum quasiparticle traps attached to a tungsten superconducting transition edge sensor patterned on a silicon substrate. The tungsten lines are voltage biased and self-regulate in the transition region. Phonons from particle interactions in the silicon deposit energy into the creating quasiparticles. The quasiparticles are trapped into the tungsten and cause its electrical resistance to increase. The resulting decrease in current through the sensor is measured with a DC SQUID array. We have been able to demonstrate xy-position resolution of /spl sim/0.3 mm for 6 keV X-rays from an /sup 55/Fe source in a 2 cm/spl times/2 cm/spl times/4 mm (4 g) detector. We describe our optimizations of the sensor design for improved energy and position. By simultaneously measuring the ionization yield we have demonstrated discrimination between electron and nuclear recoil events in a 100 g Si detector for the CDMS (Cryogenic Dark Matter Search) experiment.
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