2,921 research outputs found
Melting Pattern of Diquark Condensates in Quark Matter
Thermal color superconducting phase transitions in high density three-flavor
quark matter are investigated in the Ginzburg-Landau approach. Effects of
nonzero strange quark mass, electric and color charge neutrality, and direct
instantons are considered. Weak coupling calculations show that an interplay
between the mass and electric neutrality effects near the critical temperature
gives rise to three successive second-order phase transitions as the
temperature increases: a modified color-flavor locked (mCFL) phase (ud, ds, and
us pairings) -> a ``dSC'' phase (ud and ds pairings) -> an isoscalar pairing
phase (ud pairing) -> a normal phase (no pairing). The dSC phase is novel in
the sense that while all eight gluons are massive as in the mCFL phase, three
out of nine quark quasiparticles are gapless.Comment: minor changes in the text, fig.2 modifie
`Hidden' Symmetries of Higher Dimensional Rotating Black Holes
We demonstrate that the rotating black holes in an arbitrary number of
dimensions and without any restrictions on their rotation parameters possess
the same `hidden' symmetry as the 4-dimensional Kerr metric. Namely, besides
the spacetime symmetries generated by the Killing vectors they also admit the
(antisymmetric) Killing-Yano and symmetric Killing tensors.Comment: 4 pages, slightly extended introductio
Intrinsic electric field effects on few-particle interactions in coupled GaN quantum dots
We study the multi-exciton optical spectrum of vertically coupled GaN/AlN
quantum dots with a realistic three-dimensional direct-diagonalization approach
for the description of few-particle Coulomb-correlated states. We present a
detailed analysis of the fundamental properties of few-particle/exciton
interactions peculiar of nitride materials. The giant intrinsic electric fields
and the high electron/hole effective masses give rise to different effects
compared to GaAs-based quantum dots: intrinsic exciton-exciton coupling,
non-molecular character of coupled dot exciton wavefunction, strong dependence
of the oscillator strength on the dot height, large ground state energy shift
for dots separated by different barriers. Some of these effects make GaN/AlN
quantum dots interesting candidates in quantum information processing.Comment: 23 pages, 8 figures, 1 tabl
Chemical Compositions of Pine Resin, Rosin and Turpentine Oil From West Java
This study was conducted to identify chemical composition of merkus pine resin, rosin and turpentine oil. Initially, pine resin was separated into neutral and acidic fractions with an aqueous 4% sodium hydroxide solution. After methylation, the fraction containing turpentine oil and rosin were analyzed by gas chromatography (GC), and gas chromatograph mass spectrometry (GC-MS), respectively. The neutral fraction of pine resin and turpentine oil mainly consisted of a-pinene, D-3-carene and b-pinene. Based on mass spectral comparison, the major constituents of the acidic fraction and rosin were identified as sandaracopimaric acid, isopimaric acid, palustric acid, dehydroabietic acid, abietic acid, neoabietic acid, and merkusic acid. The major component of the acidic fractions was palustric acid, while that of rosin was abietic acid. Using TC (tough column) 1 and TC 5 columns, levopimaric acid could not be separated from rosin or acidic fraction of pine resin of Indonesian Pinus merkusii
Closed conformal Killing-Yano tensor and geodesic integrability
Assuming the existence of a single rank-2 closed conformal Killing-Yano
tensor with a certain symmetry we show that there exist mutually commuting
rank-2 Killing tensors and Killing vectors. We also discuss the condition of
separation of variables for the geodesic Hamilton-Jacobi equations.Comment: 17 pages, no figure, LaTe
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