1,409 research outputs found
Extraction of Quark Transversity Distribution and Collins Fragmentation Functions with QCD Evolution
We study the transverse momentum dependent (TMD) evolution of the Collins
azimuthal asymmetries in annihilations and semi-inclusive hadron
production in deep inelastic scattering (SIDIS) processes. All the relevant
coefficients are calculated up to the next-to-leading logarithmic (NLL) order
accuracy. By applying the TMD evolution at the approximate NLL order in the
Collins-Soper-Sterman (CSS) formalism, we extract transversity distributions
for and quarks and Collins fragmentation functions from current
experimental data by a global analysis of the Collins asymmetries in
back-to-back di-hadron productions in annihilations measured by BELLE
and BABAR Collaborations and SIDIS data from HERMES, COMPASS, and JLab HALL A
experiments. The impact of the evolution effects and the relevant theoretical
uncertainties are discussed. We further discuss the TMD interpretation for our
results, and illustrate the unpolarized quark distribution, transversity
distribution, unpolarized quark fragmentation and Collins fragmentation
functions depending on the transverse momentum and the hard momentum scale. We
make detailed predictions for future experiments and discuss their impact.Comment: 45 pages, 31 figure
Data Detection and Code Channel Allocation for Frequency-Domain Spread ACO-OFDM Systems Over Indoor Diffuse Wireless Channels
Future optical wireless communication systems promise to provide high-speed data transmission in indoor diffuse environments. This paper considers frequency-domain spread asymmetrically clipped optical orthogonal frequency-division multiplexing (ACOOFDM) systems in indoor diffuse channels and aims to develop efficient data detection and code channel allocation schemes. By exploiting the frequency-domain spread concept, a linear multi-code detection scheme is proposed to maximize the signal to interference plus noise ratio (SINR) at the receiver. The achieved SINR and bit error ratio (BER) performance are analyzed. A computationally efficient code channel allocation algorithm is proposed to improve the BER performance of the frequency-domain spread ACO-OFDM system.
Numerical results show that the frequency-domain spread ACO-OFDM system outperforms conventional ACO-OFDM systems in indoor diffuse channels. Moreover, the proposed linear multi-code detection and code channel allocation algorithm can improve the performance of optical peak-to-average power ratio (PAPR
Effect of Combined PD-1 and IL-6 Blockade on K-ras Mutant Lung Cancer
https://openworks.mdanderson.org/sumexp21/1212/thumbnail.jp
Topological holographic quench dynamics in a synthetic dimension
The notion of topological phases extended to dynamical systems stimulates
extensive studies, of which the characterization of non-equilibrium topological
invariants is a central issue and usually necessitates the information of
quantum dynamics in both the time and spatial dimensions. Here we combine the
recently developed concepts of the dynamical classification of topological
phases and synthetic dimension, and propose to efficiently characterize
photonic topological phases via holographic quench dynamics. A pseudo spin
model is constructed with ring resonators in a synthetic lattice formed by
frequencies of light, and the quench dynamics is induced by initializing a
trivial state which evolves under a topological Hamiltonian. Our key prediction
is that the complete topological information of the Hamiltonian is extracted
from quench dynamics solely in the time domain, manifesting holographic
features of the dynamics. In particular, two fundamental time scales emerge in
the quench dynamics, with one mimicking the Bloch momenta of the topological
band and the other characterizing the residue time evolution of the state after
quench. For this a dynamical bulk-surface correspondence is obtained in time
dimension and characterizes the topology of the spin model. This work also
shows that the photonic synthetic frequency dimension provides an efficient and
powerful way to explore the topological non-equilibrium dynamics.Comment: Compared to the previous submission, we made changes to figures and
revised some discussion
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