46,669 research outputs found
Integrated circuit random-access memory decoder
Decoder circuit with complementary-symmetry circuit configuration composed of MOS and n-p-n bipolar devices minimizes power consumption. Emitter-follower drive scheme results in low power dissipation and high speed operation
Low-power integrated-circuit driver for ferrite-memory word lines
Composite circuit uses both n-p-n bipolar and p-channel MOS transistors /BIMOS/. The BIMOS driver provides 1/ ease of integrated circuit construction, 2/ low standby power consumption, 3/ bidirectional current pulses, and 4/ current-pulse amplitudes and rise times independent of active device parameters
Equation of state from lattice QCD
Recent results on the equation of state from lattice QCD are reviewed. The
lattice technique and previous results are shortly discussed. New results for
physical quark masses and two sets of lattice spacings are presented. The
pressure, energy density, entropy density, speed of sound and quark number
susceptibilities are determined.Comment: 10 pages, 11figures. Plenary talk presented at the Quark Matter 2005
conferenc
Notes on Certain (0,2) Correlation Functions
In this paper we shall describe some correlation function computations in
perturbative heterotic strings that, for example, in certain circumstances can
lend themselves to a heterotic generalization of quantum cohomology
calculations. Ordinary quantum chiral rings reflect worldsheet instanton
corrections to correlation functions involving products of Dolbeault cohomology
groups on the target space. The heterotic generalization described here
involves computing worldsheet instanton corrections to correlation functions
defined by products of elements of sheaf cohomology groups. One must not only
compactify moduli spaces of rational curves, but also extend a sheaf
(determined by the gauge bundle) over the compactification, and linear sigma
models provide natural mechanisms for doing both. Euler classes of obstruction
bundles generalize to this language in an interesting way.Comment: 51 pages, LaTeX; v2: typos fixed; v3: more typos fixe
Finite temperature and chemical potential in lattice QCD and its critical point
We propose a method to study lattice QCD at finite temperature (T) and
chemical potential (\mu). We compare the method with direct results and with
the Glasgow method by using n_f=4 QCD at Im(\mu)\neq0. We locate the critical
endpoint (E) of QCD on the Re(\mu)-T plane. We use n_f=2+1 dynamical staggered
quarks with semi-realistic masses on L_t=4 lattices. Our results are based on
{\cal{O}}(10^3-10^4) configurations.Comment: 8 pages, 4 figures. Talk given at the XXX. Hirschegg Workshop on
Ultrarelativistic Heavy-Ion Collisions, January 13-19, 200
Propagation of ultrahigh energy cosmic rays and compact sources
The clustering of ultrahigh energy (>10^{20} eV) cosmic rays (UHECR) suggests
that they might be emitted by compact sources. Statistical analysis (Dubovsky
et al., 2000) estimated the source density. We extend their analysis to give
also the confidence intervals (CI) for the source density using a.) no
assumptions on the relationship between clustered and unclustered events; b.)
nontrivial distributions for the source luminosities and energies; c.) the
energy dependence of the propagation. We also determine the probability that a
proton created at a distance r with energy E arrives at earth above a threshold
E_c. Using this function one can determine the observed spectrum just by one
numerical integration for any injection spectrum. The observed 14 UHECR events
above 10^{20} eV with one doublet gives for the source densities
180_{-165}^{+2730}\cdot 10^{-3} Mpc^{-3} (on the 68% confidence level).Comment: 4 pages, 1 figure, talk to be presented at the 27th International
Cosmic Ray Conference, Hamburg, Germany, August 7-15, 200
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