17,413 research outputs found
D0 Silicon Microstrip Tracker fro Run IIa
We briefly describe the production, installation and commissioning of the new
800,000 channel D0 Silicon Microstrip Tracker to be used for the 2 fb of
the Run IIa at the Tevatron.Comment: 5 Latex pages, 3 figures. to appear in proceedings of Como 200
Recent Results Addressing the KARMEN Timing Anomaly
Recent resuls from experiments at Fermilab and the Paul Scherrer Institute
have constrained the parameter space available for a hypothetical particle
produced in the decay . This decay has been invoked
to explain a peculiar feature of an event arrival time distribution observed in
the KARMEN neutrino experiment.Comment: 5 pages, 1 figure. Presented at the Conference on the Intersections
of Particle and Nuclear Physics (CIPANP 2000), Quebec City, May 200
Updated Search for Electron Antineutrino Appearance at MiniBooNE
The MiniBooNE experiment at Fermilab has updated its search for \nu_\mu-bar
-> \nu_e-bar oscillations with data collected through May 2011. This represents
a statistics increase of 52% over the result published in 2010. The data favor
LSND-like oscillations over a background-only hypothesis at the 91.1%
confidence level. While the new result remains equally consistent with LSND,
the compatibility with the background-only hypothesis is improved. An excess of
38.6 +- 18.5 \nu_e-like events below 475 MeV is observed, consistent with the
observation of such an excess in neutrino mode.Comment: 3 pages, 1 figure. Proceedings of the PANIC 11 conference, Cambridge,
Mass., July 2011 Corrected typographical error in Table
From an axiological standpoint
I maintain that intrinsic value is the fundamental concept of axiology. Many contemporary philosophers disagree; they say the proper object of value theory is final value. I examine three accounts of the nature of final value: the first claims that final value is nonâinstrumental value; the second claims that final value is the value a thing has as an end; the third claims that final value is ultimate or nonâderivative value. In each case, I argue that the concept of final value described is either identical with the classical notion of intrinsic value or is not a plausible candidate for the primary concept of axiology
A Single-armed Manta-board as a New Diver-controlled Planing Board and Its Use for Underwater Surveys
Due to inadequacies of previous underwater towing techniques and the special needs of a recent underwater survey, a modified mania-board technique was developed. With this new technique, the diver holds on to the manta-board with one arm; consequently, the board is referred to as a single-armed manta-board (sam-board). The sam-board proved inexpensive and highly maneuverable, allowing the divers to freely collect samples or record information. Through some experimenting with the board and changing some of the variables, such as rope lengths, towing speeds, etc., a highly efficient towing method can be achieved. Preplanning and strict diving safety procedures must, however, be implemented to assure efficiency. This paper presents the materials, guidelines for board construction, equipment, and preplanning and diving safety procedures necessary for the sam-board towing operation
A cryocooler for applications requiring low magnetic and mechanical interference
A very low-power, low-interference Stirling cryocooler is being developed based on principles and techniques described in several previous publications over the last four years. It differs in several important details from those built previously. It uses a tapered displacer based upon an analytical optimization procedure. The displacer is driven by an auxiliary piston and cylinder (rather than by mechanical linkage) using some of the working fluid itself to provide the driving force. This provides smooth, vibration-free motion, and, more importantly, allows complete mechanical and spatial separation of the cryostat from the pressure-wave generator. Either of two different pressure-wave generators can be used. One is a non-contaminating, unlubricated ceramic piston and cylinder. The other is a compressed-air-operated rubber diaphragm with motor-driven valves to cycle the pressure between appropriate limits
Semi-local Quantum Criticality and the Instability of Extremal Planar Horizons
We show that the Aretakis instability of compact extremal horizons persists
in the planar case of interest to holography and discuss its connection with
the emergence of "semi-local quantum criticality" in the field theory dual. In
particular, the spatially localized power-law decay of this critical phase
corresponds to spatially localized power-law growth of stress-energy on the
horizon. For near-extremal black holes these phenomena occur transiently over
times of order the inverse temperature. The boundary critical phase is
characterized by an emergent temporal conformal symmetry, and the bulk
instability seems to be essential to preserving the symmetry in the presence of
interactions. We work primarily in the solvable example of charged scalar
perturbations of five-dimensional (near-)extremal planar Reissner-Nordstr\"om
anti-de Sitter spacetime and argue that the conclusions hold more generally.Comment: 23 pages. v2 contains a reference updat
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