21,139 research outputs found
TEC enhancement due to energetic electrons above Taiwan and the West Pacific
The energetic electrons of the inner radiation belt during a geomagnetic
disturbance can penetrate in the forbidden range of drift shells located at the
heights of the topside equatorial ionosphere (<1000 km). A good correlation was
previously revealed between positive ionospheric storms and intense fluxes of
quasi-trapped 30-keV electrons at ~900 km height in the forbidden zone. In the
present work, we use statistics to validate an assumption that the intense
electron fluxes in the topside equatorial ionosphere can be an important source
of the ionization in the low-latitude ionosphere. The data on the energetic
electrons were obtained from polar orbiting satellites over the periods of the
62 strong geomagnetic storms from 1999 to 2006. Ionospheric response to the
selected storms was determined using global ionospheric maps of vertical total
electron content (VTEC). A case-event study of a major storm on 9 November 2004
provided experimental evidence in support to the substantial ionization effect
of energetic electrons during positive ionospheric storms at the low latitudes.
Statistical analysis of nine magnetic storms indicated that the VTEC increases
coincided with and coexisted with intense 30-keV electron fluxes irrespective
of local time and phase of geomagnetic storm. We concluded that extremely
intense fluxes of the 30-keV electrons in the topside low-latitude ionosphere
can contribute ~ 10 - 30 TECU to the localized positive ionospheric storms.Comment: 15 pages, 4 figures, 1 table accepted for publication in Terrestrial,
Atmospheric and Oceanic Sciences (TAO), Dec. 2012 A special issue on
"Connection of solar and heliospheric activities with near-Earth space
weather: Sun-Earth connection
Adhesion between atomically pure metallic surfaces Final report
Metallic adhesion from compression loads resulting in plastic deformatio
Adhesion between atomically pure metallic surfaces, part 4 Semiannual report
Adhesion between atomically pure metal surface
Adhesion between automatically pure metallic surfaces, part 4 Semiannual report
Contact resistance measurements to determine adhesion between atomically pure metallic surface
Scalable quantum computing with Josephson charge qubits
A goal of quantum information technology is to control the quantum state of a
system, including its preparation, manipulation, and measurement. However,
scalability to many qubits and controlled connectivity between any selected
qubits are two of the major stumbling blocks to achieve quantum computing (QC).
Here we propose an experimental method, using Josephson charge qubits, to
efficiently solve these two central problems. The proposed QC architecture is
scalable since any two charge qubits can be effectively coupled by an
experimentally accessible inductance. More importantly, we formulate an
efficient and realizable QC scheme that requires only one (instead of two or
more) two-bit operation to implement conditional gates.Comment: 4 pages, 2 figure
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