11,391 research outputs found
Quark condensate in one-flavor QCD
We compute the condensate in QCD with a single quark flavor using numerical
simulations with the overlap formulation of lattice fermions. The condensate is
extracted by fitting the distribution of low lying eigenvalues of the Dirac
operator in sectors of fixed topological charge to the predictions of Random
Matrix Theory. Our results are in excellent agreement with estimates from the
orientifold large-N_c expansion.Comment: 12 pages, 4 figures, REVTeX4, v2: Small changes, extended
introduction, published versio
Chiral properties of two-flavor QCD in small volume and at large lattice spacing
We present results from simulations of two flavors of dynamical overlap
fermions on 8^4 lattices at three values of the sea quark mass and a lattice
spacing of about 0.16 fm. We measure the topological susceptibility and the
chiral condensate. A comparison of the low-lying spectrum of the overlap
operator with predictions from random matrix theory is made. To demonstrate the
effect of the dynamical fermions, we compare meson two-point functions with
quenched results. Algorithmic improvements over a previous publication and the
performance of the algorithm are discussed.Comment: 16 pages, 12 figure
Room Temperature Electrical Detection of Spin Coherence in C60
An experimental demonstration of electrical detection of coherent spin motion
of weakly coupled, localized electron spins in thin Fullerene C60 films at room
temperature is presented. Pulsed electrically detected magnetic resonance
experiments on vertical photocurrents through Al/C60/ZnO samples showed that an
electron spin Rabi oscillation is reflected by transient current changes. The
nature of possible microscopic mechanisms responsible for this spin to charge
conversion as well as its implications for the readout of endohedral Fullerene
(N@C60) spin qubits are discussed.Comment: 4 pages, 3 figure
Acoustic performance of inlet multiple-pure-tone suppressors installed on NASA quiet engine C
The length of multiple-pure-tone (MPT) treatment required to reasonably suppress the MPT's produced by a supersonic tip speed fan was defined. Other suppression, broadband, and blade passing frequency, which might be accomplished were also determined. The experimental results are presented in terms of both far-field and duct acoustic data
New records of plants fed upon by the uncommon Heteropterans Cyrtocoris egeris Packauskas & Schaefer and C. trigonus (Germar) (Hemiptera: Cyrtocoridae) in South America.
During March 2000, nymphs and adults of the cyrtocorid bugs Cyrtocoris egeris Packauskas & Schaefer and C. trigonus (Germar) were observed on two different plants at two different localities. In Brazil (Londrina, Paraná State) adult C. trigonus were found feeding on stems of the weed plant arrow leaf sida, Sida rhombifolia L. (Malvaceae). Despite egg deposition in the laboratory, nymphs did not develop on this plant. In Argentina (Reconquista, Santa Fé Province), nymphs and adults of C. egeris were observed feeding on immature soybean [Glycine max (L.) Merrill] pods. Under laboratory conditions, nymphs of neither species could be reared beyond the third instar
Prompt activation analysis of coal and iron ore
Prepared for U.S. Dept. of Mines, Bureau of MinesAlso issued as a M.S. thesis in the Dept. of Nuclear Engineering, 1970Includes bibliographical references (leaf 47)H018089
A Sensor Failure Simulator for Control System Reliability Studies
A real-time Sensor Failure Simulator (SFS) was designed and assembled for the Advanced Detection, Isolation, and Accommodation (ADIA) program. Various designs were considered. The design chosen features an IBM-PC/XT. The PC is used to drive analog circuitry for simulating sensor failures in real-time. A user defined scenario describes the failure simulation for each of the five incoming sensor signals. Capabilities exist for editing, saving, and retrieving the failure scenarios. The SFS has been tested closed-loop with the Controls Interface and Monitoring (CIM) unit, the ADIA control, and a real-time F100 hybrid simulation. From a productivity viewpoint, the menu driven user interface has proven to be efficient and easy to use. From a real-time viewpoint, the software controlling the simulation loop executes at greater than 100 cycles/sec
- …