8,019 research outputs found
Chromomagnetic instability in dense quark matter
The results for the Debye and Meissner screening masses of the gluons and the
photon in the case of neutral and beta-equilibrated dense two-flavor quark
matter are presented. In the limits of the normal phase and the ideal
two-flavor color superconducting phase, the screening masses coincide with the
known results. Most interestingly, we find that the Meissner screening masses
squared can be negative, indicating a plasma-type chromomagnetic instability in
dense quark matter.Comment: 5 pages and 2 figures. To appear in Phys. Rev. D; version slightly
shortened on request of editor
The gapless 2SC phase
Recent results on the gapless 2SC phase are reviewed. These include: the
thermal stability under the constraint of the local charge neutrality
condition, the properties at zero and nonzero temperatures, and the color
screening properties.Comment: To appear in the proceedings of 6th Conference on Strong and
Electroweak Matter 2004 (SEWM04), Helsinki, Finland, 16-19 Jun 2004. Typos
correcte
Visual attributes of subliminal priming images impact conscious perception of facial expressions
We investigated, in young healthy participants, how the affective content of subliminally presented priming images and their specific visual attributes impacted conscious perception of facial expressions. The priming images were broadly categorized as aggressive, pleasant, or neutral and further subcategorized by the presence of a face and by the centricity (egocentric or allocentric vantage-point) of the image content. Participants responded to the emotion portrayed in a pixelated target-face by indicating via key-press if the expression was angry or neutral. Response time to the neutral target face was significantly slower when preceded by face primes, compared to non-face primes (p < 0.05, Bonferroni corrected). In contrast, faster RTs were observed when angry target faces were preceded by face compared to non-face primes. In addition, participants’ performance was worse when a priming image contained an egocentric face compared to when it contained either an allocentric face or an egocentric non-face. The results suggest a significant impact of the visual features of the priming image on conscious perception of face expression.Published versio
Spontaneous current generation in the gapless 2SC phase
It is found that, except chromomagnetic instability, the gapless 2SC phase
also exhibits a paramagnetic response to the perturbation of an external color
neutral baryon current. The spontaneously generated baryon current driven by
the mismatch is equivalent to the one-plane wave LOFF state. We describe the
2SC phase in the nonlinear realization framework, and show that each
instability indicates the spontaneous generation of the corresponding pseudo
Nambu-Golstone current. We show this Nambu-Goldstone currents generation state
covers the gluon phase as well as the one-plane wave LOFF state. We further
point out that, when charge neutrality condition is required, there exists a
narrow unstable LOFF (Us-LOFF) window, where not only off-diagonal gluons but
the diagonal 8-th gluon cannot avoid the magnetic instability. We discuss that
the diagonal magnetic instability in this Us-LOFF window cannot be cured by
off-diagonal gluon condensate in color superconducting phase, and it will also
show up in some constrained Abelian asymmetric superfluid/superconducting
system.Comment: 8 pages, no figure, final version to appear in PR
An Analytic Solution of Hydrodynamic Equations with Source Terms in Heavy Ion Collisions
The energy and baryon densities in heavy ion collisions are estimated by
analytically solving a 1+1 dimensional hydrodynamical model with source terms.
Particularly, a competition between the energy and baryon sources and the
expansion of the system is discussed in detail.Comment: LaTeX2e, 7 pages, 4 postscript figures, submitted to Int. J. Mod.
Phys.
Assessment of Long-Term Watershed Management on Reservoir Phosphorus Concentrations and Export Fluxes.
Source water nutrient management to prevent eutrophication requires critical strategies to reduce watershed phosphorus (P) loadings. Shanxi Drinking-Water Source Area (SDWSA) in eastern China experienced severe water quality deterioration before 2010, but showed considerable improvement following application of several watershed management actions to reduce P. This paper assessed the changes in total phosphorus (TP) concentrations and fluxes at the SDWSA outlet relative to watershed anthropogenic P sources during 2005⁻2016. Overall anthropogenic P inputs decreased by 21.5% over the study period. Domestic sewage, livestock, and fertilizer accounted for (mean ± SD) 18.4 ± 0.6%, 30.1 ± 1.9%, and 51.5 ± 1.5% of total anthropogenic P inputs during 2005⁻2010, compared to 24.3 ± 2.7%, 8.8 ± 10.7%, and 66.9 ± 8.0% for the 2011⁻2016 period, respectively. Annual average TP concentrations in SDWSA decreased from 0.041 ± 0.019 mg/L in 2009 to 0.025 ± 0.013 mg/L in 2016, a total decrease of 38.2%. Annual P flux exported from SDWSA decreased from 0.46 ± 0.04 kg P/(ha·a) in 2010 to 0.25 ± 0.02 kg P/(ha·a) in 2016, a decrease of 44.9%. The success in reducing TP concentrations was mainly due to the development of domestic sewage/refuse collection/treatment and improved livestock management. These P management practices have prevented harmful algal blooms, providing for safe drinking water
The electromagnetic form factors in the holographic QCD
In this study, we employ a modified soft-wall holographic model with four
flavors to investigate the meson spectra, decay constants, electromagnetic form
factors, and charge radius of various mesons. We obtain the spectra for vector,
axial vector, and pseudoscalar mesons. Decay constants are calculated and
compared with experimental and lattice QCD data. The pion and kaon
electromagnetic form factors are compared with the experimental data, and a
good agreement is achieved for the kaon at low . For the charmed mesons,
the electromagnetic form factors of the and and electric form
factors of the and are well consistent with the lattice QCD
data. Moreover, the electric, magnetic, and quadrupole form factors are
predicted for the , , , , , and mesons.
Furthermore, the charge radius of the vector, axial vector, and pseudoscalars,
including the strange and charmed mesons, are computed
Inhomogeneity driven by Higgs instability in gapless superconductor
The fluctuations of the Higgs and pseudo Nambu-Goldstone fields in the 2SC
phase with mismatched pairing are described in the nonlinear realization
framework of the gauged Nambu--Jona-Lasinio model. In the gapless 2SC phase,
not only Nambu-Goldstone currents can be spontaneously generated, but the Higgs
field also exhibits instablity. The Nambu-Goldstone currents generation
indicates the formation of the single plane wave LOFF state and breaks rotation
symmetry, while the Higgs instability favors spatial inhomogeneity and breaks
translation invariance. In this paper, we focus on the Higgs instability which
has not drawn much attention yet. The Higgs instability cannot be removed
without a long range force, thus it persists in the gapless superfluidity and
induces phase separation. In the case of g2SC state, the Higgs instability can
only be partially removed by the electric Coulomb energy. However, it is not
excluded that the Higgs instability might be completely removed in the charge
neutral gCFL phase by the color Coulomb energy.Comment: 21 pages, 5 figure
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