80,992 research outputs found
Single inclusive hadron production in pA collisions at NLO
We study single inclusive forward hadron production in high energy
proton-nucleus collisions at next-to-leading order in the Color Glass
Condensate framework. Recent studies have shown that the next-to-leading order
corrections to this process are large and negative at large transverse
momentum, leading to negative cross sections. We propose to overcome this
difficulty by introducing an explicit rapidity factorization scale when
subtracting the rapidity divergence into the evolution of the target.Comment: 6 pages, 2 figures. Proceedings of DIS 2016, 11-15 April 2016, DESY
Hamburg, German
Single inclusive forward hadron production at next-to-leading order
We discuss single inclusive hadron production from a high energy quark
scattering off a strong target color field in the Color Glass Condensate
formalism. Recent calculations of this process at the next-to-leading order
accuracy have led to negative cross sections at large transverse momenta. We
identify the origin of this problem as an oversubtraction of the rapidity
divergence into the Balitsky-Kovchegov evolution equation for the target. We
propose a new way to implement the kinematical restriction on the emitted
gluons to overcome this difficulty.Comment: 12 pages, 9 figures. v2: matches published versio
Redistribution of phase fluctuations in a periodically driven cuprate superconductor
We study the thermally fluctuating state of a bi-layer cuprate superconductor
under the periodic action of a staggered field oscillating at optical
frequencies. This analysis distills essential elements of the recently
discovered phenomenon of light enhanced coherence in YBaCuO,
which was achieved by periodically driving infrared active apical oxygen
distortions. The effect of a staggered periodic perturbation is studied using a
Langevin and Fokker-Planck description of driven, coupled Josephson junctions,
which represent two neighboring pairs of layers and their two plasmons. In a
toy model including only two junctions, we demonstrate that the external
driving leads to a suppression of phase fluctuations of the low-energy plasmon,
an effect which is amplified via the resonance of the high energy plasmon. When
extending the modeling to the full layers, we find that this reduction becomes
far more pronounced, with a striking suppression of the low-energy
fluctuations, as visible in the power spectrum. We also find that this effect
acts onto the in-plane fluctuations, which are reduced on long length scales.
All these findings provide a physical framework to describe light control in
cuprates
QCD Sum Rule Analysis of Heavy Quarkonium Hybrids
We have studied the charmonium and bottomonium hybrid states with various
quantum numbers in QCD sum rules. At leading order in , the
two-point correlation functions have been calculated up to dimension six
including the tri-gluon condensate and four-quark condensate. After performing
the QCD sum rule analysis, we have confirmed that the dimension six condensates
can stabilize the hybrid sum rules and allow the reliable mass predictions. We
have updated the mass spectra of the charmonium and bottomonium hybrid states
and identified that the negative-parity states with form the lightest hybrid supermultiplet while the positive-parity
states with belong to a heavier hybrid
supermultiplet.Comment: 7 pages, 1 figures. Some minor edits have been made. Presentation at
the DPF 2013 Meeting of the American Physical Society Division of Particles
and Fields, Santa Cruz, California, August 13-17, 201
Exploring the Spectrum of Heavy Quarkonium Hybrids with QCD Sum Rules
QCD Laplace sum rules are used to calculate heavy quarkonium (charmonium and
bottomonium) hybrid masses in several distinct channels. Previous
studies of heavy quarkonium hybrids did not include the effects of
dimension-six condensates, leading to unstable sum rules and unreliable mass
predictions in some channels. We have updated these sum rules to include
dimension-six condensates, providing new mass predictions for the spectra of
heavy quarkonium hybrids. We confirm the finding of other approaches that the
negative-parity states form the lightest hybrid
supermultiplet and the positive-parity
states are members of a heavier supermultiplet. Our results disfavor a pure
charmonium hybrid interpretation of the , in agreement with previous
work.Comment: Presented by RTK at the Theory Canada 9 Conference, held at Wilfrid
Laurier University in June 2014. Submitted for the conference proceedings to
be published in the Canadian Journal of Physics. 5 pages, 1 figure. Version
2: reference added, typo correcte
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