22,079 research outputs found
On the temperature dependence of correlation functions in the space like direction in hot QCD
We study the temperature dependence of quark antiquark correlations in the
space like direction. In particular, we predict the temperature dependence of
space like Bethe-Salpeter amplitudes using recent Lattice gauge data for the
space like string potential. We also investigate the effect of the space like
string potential on the screening mass and discuss possible corrections which
may arise when working with point sources.Comment: 15 pages 8 figures (not included, will be sent on request),
(SUNY-NTG-94-3
A para-differential renormalization technique for nonlinear dispersive equations
For \alpha \in (1,2) we prove that the initial-value problem \partial_t
u+D^\alpha\partial_x u+\partial_x(u^2/2)=0 on \mathbb{R}_x\times\mathbb{R}_t;
u(0)=\phi, is globally well-posed in the space of real-valued L^2-functions. We
use a frequency dependent renormalization method to control the strong low-high
frequency interactions.Comment: 42 pages, no figure
Controlling the transport of an ion: Classical and quantum mechanical solutions
We investigate the performance of different control techniques for ion
transport in state-of-the-art segmented miniaturized ion traps. We employ
numerical optimization of classical trajectories and quantum wavepacket
propagation as well as analytical solutions derived from invariant based
inverse engineering and geometric optimal control. We find that accurate
shuttling can be performed with operation times below the trap oscillation
period. The maximum speed is limited by the maximum acceleration that can be
exerted on the ion. When using controls obtained from classical dynamics for
wavepacket propagation, wavepacket squeezing is the only quantum effect that
comes into play for a large range of trapping parameters. We show that this can
be corrected by a compensating force derived from invariant based inverse
engineering, without a significant increase in the operation time
Many-Body Dynamics and Exciton Formation Studied by Time-Resolved Photoluminescence
The dynamics of exciton and electron-hole plasma populations is studied via
time-resolved photoluminescence after nonresonant excitation. By comparing the
peak emission at the exciton resonance with the emission of the continuum, it
is possible to experimentally identify regimes where the emission originates
predominantly from exciton and/or plasma populations. The results are supported
by a microscopic theory which allows one to extract the fraction of bright
excitons as a function of time.Comment: 11 pages, 5 figure
CeRuPO: A rare example of a Ferromagnetic Kondo lattice
We have determined the physical ground state properties of the compounds
CeRuPO and CeOsPO by means of magnetic susceptibility chi(T), specific heat
C(T), electrical resistivity rho(T), and thermopower S(T) measurements. chi(T)
reveals a trivalent 4f1 cerium state in both compounds. For CeRuPO a pronounced
decrease of rho(T) below 50K indicates the onset of coherent Kondo scattering
which is confirmed by enhanced S(T). The temperature and magnetic field
dependence of chi(T) and C(T) evidence ferromagnetic (FM) order at TC=15K.
Thus, CeRuPO seems to be one of the rare example of a FM Kondo lattice. In
contrast, CeOsPO shows antiferromagnetic order at TN=4.4K despite only minor
changes in lattice parameters and electronic configuration. Additional 31P NMR
results support these scenarios. LSDA+U calculations evidence a quasi two
dimensional electronic band structure, reflecting a strong covalent bonding
within the CeO and RuP layers and a weak ionic like bonding between the layers.Comment: accepted in Phys. Rev. B, high quality figures:
http://www.cpfs.mpg.de/~krellner
Fluctuations of particle ratios and the abundance of hadronic resonances
In this letter we will argue that the event-by-event fluctuations of the
ratio of positively over negatively charged pions provides a measurements of
the number of rho and omega mesons right after hadronization. This finding can
be utilized to put the hypothesis of chemical equilibration in relativistic
heavy ion collisions to a test.Comment: 4 pages. No figure. Uses revtex with prl, aps, and multicol style
Entanglement in the dispersive interaction of trapped ions with a quantized field
The mode-mode entanglement between trapped ions and cavity fields is
investigated in the dispersive regime. We show how a simple initial preparation
of Gaussian coherent states and a postselection may be used to generate
motional non-local mesoscopic states (NLMS) involving ions in different traps.
We also present a study of the entanglement induced by dynamical Stark-shifts
considering a cluster of N-trapped ions. In this case, all entanglement is due
to the dependence of the Stark-shifts on the ions' state of motion manifested
as a cross-Kerr interaction between each ion and the field.Comment: 10 pages, 5 figures, corrected typo
Excitonic Photoluminescence in Semiconductor Quantum Wells: Plasma versus Excitons
Time-resolved photoluminescence spectra after nonresonant excitation show a
distinct 1s resonance, independent of the existence of bound excitons. A
microscopic analysis identifies excitonic and electron-hole plasma
contributions. For low temperatures and low densities the excitonic emission is
extremely sensitive to even minute optically active exciton populations making
it possible to extract a phase diagram for incoherent excitonic populations.Comment: 9 pages, 4 figure
Evidence of early multi-strange hadron freeze-out in high energy nuclear collisions
Recently reported transverse momentum distributions of strange hadrons
produced in Pb(158AGeV) on Pb collisions and corresponding results from the
relativistic quantum molecular dynamics (RQMD) approach are examined. We argue
that the experimental observations favor a scenario in which multi-strange
hadrons are formed and decouple from the system rather early at large energy
densities (around 1 GeV/fm). The systematics of the strange and non-strange
particle spectra indicate that the observed transverse flow develops mainly in
the late hadronic stages of these reactions.Comment: 4 pages, 4 figure
Диагностика сердечной недостаточности с сохраненной систолической функцией левого желудочка у пациентов с артериальной гипертензией
КАРДИОЛОГИЯГИПЕРТЕНЗИЯСЕРДЕЧНАЯ НЕДОСТАТОЧНОСТЬ ЗАСТОЙНАЯ /ДИАГНОСТИКАИНСТРУКЦИИ ПО ПРИМЕНЕНИ
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