cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Elastic backscattering of quantum spin Hall edge modes from Coulomb interactions with non-magnetic impurities
Creators: name: McGinley, Max
name: Cooper, Nigel R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We demonstrate that electrostatic interactions between helical electrons at the edge of a quantum spin Hall insulator and a dynamical impurity can induce quasi-elastic backscattering. Modelling the impurity as a two-level system, we show that transitions between counterpropagating Kramers-degenerate electronic states can occur without breaking time-reversal symmetry, provided that the impurity also undergoes a transition. The associated electrical resistance has a weak temperature dependence down to a non-universal temperature scale. Our results extend the range of known backscattering mechanisms in helical edge modes to include scenarios where electron tunnelling out of the system is absent.
description: 6 + 5 pages, 3 figures
New clues on outburst mechanisms and improved spectroscopic elements of the black-hole binary V4641 Sagittarii
Creators: name: Lindstrom, C.
name: Griffin, J.
name: Kiss, L. L.
name: Uemura, M.
name: Derekas, A.
name: Meszaros, Sz.
name: Szekely, P.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present spectroscopic observations of the black-hole binary V4641 Sagittarii, obtained between 4th July 2004 and 28th March 2005, which cover the minor outburst of the star in early July 2004 and quiescence variations on 19 nights scattered over six months. During the outburst, the star peaked approximately 3 magnitudes brighter than usual, and our spectra were dominated by broad hydrogen, helium and iron emission lines. The very first spectra showed P Cygni profiles, which disappeared within a few hours, indicating rapid changes in matter ejection. The H-alpha line had multiple components, one being a broad blue-shifted wing exceeding 5000 km/s. During a simultaneously observed 10-min photometric flare-up, the equivalent width of the H-alpha line temporarily decreased, implying that it was a flare of the continuum. The overall spectral appearance was similar to that observed in the 1999 September active phase, which suggests that similar mass-ejection processes were associated with both eruptions. In quiescence, the spectra were those of the early-type secondary star showing its orbital motion around the primary. By measuring cross-correlation radial velocities, we give an improved set of spectroscopic elements. Whereas we measure the same velocity amplitude (K_2=211.3+/-1.0 km/s), within errors, as Orosz et al. (2001), our centre-of-mass velocity (v_gamma=72.7+/-3.3 km/s) differs significantly from the previously published value (107.4+/-m2.9 km/s). However, we find evidence that the difference is caused by a systematic error in data reduction in the previous study, rather than by gravitational effects of an invisible third component.
description: 9 pages, 8 figures, accepted for publication in MNRAS
Semiclassical quantisation of space-times with apparent horizons
Creators: name: Dasgupta, Arundhati
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Coherent or semiclassical states in canonical quantum gravity describe the classical Schwarzschild space-time. By tracing over the coherent state wavefunction inside the horizon, a density matrix is derived. Bekenstein-Hawking entropy is obtained from the density matrix, modulo the Immirzi parameter. The expectation value of the area and curvature operator is evaluated in these states. The behaviour near the singularity of the curvature operator shows that the singularity is resolved. We then generalise the results to space-times with spherically symmetric apparent horizons.
description: 52 pages, 4 figures
Khoury, Adel Theodor: Was ist los in der islamischen Welt?
Creators: name: Schütz, Georg
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 41 Nr. 2 (1992): Ökumenische Rundschau, Band 41, Heft 2
The Neutrino Response of Low-Density Neutron Matter from the Virial Expansion
Creators: name: Horowitz, C. J.
name: Schwenk, A.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Nuclear Theory (nucl-th)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We generalize our virial approach to study spin-polarized neutron matter and the consistent neutrino response at low densities. In the long-wavelength limit, the virial expansion makes model-independent predictions for the density and spin response, based only on nucleon-nucleon scattering data. Our results for the neutrino response provide constraints for random-phase approximation or other model calculations, and we compare the virial vector and axial response to response functions used in supernova simulations. The virial expansion is suitable to describe matter near the supernova neutrinosphere, and this work extends the virial equation of state to predict neutrino interactions in neutron matter.
description: 8 pages, 5 figures, minor additions, to appear in Phys. Lett. B
Bounded and unitary elements in pro-C^*-algebras
Creators: name: Harti, Rachid El
name: Lukács, Gábor
Publisher: name: arXiv
Year: 2005
Subjects: subject: Category Theory (math.CT)
subject: Operator Algebras (math.OA)
subject: FOS: Mathematics
subject: 18A05 46H05 46J05 46K05

description: A pro-C^*-algebra is a (projective) limit of C^*-algebras in the category of topological *-algebras. From the perspective of non-commutative geometry, pro-C^*-algebras can be seen as non-commutative k-spaces. An element of a pro-C^*-algebra is bounded if there is a uniform bound for the norm of its images under any continuous *-homomorphism into a C^*-algebra. The *-subalgebra consisting of the bounded elements turns out to be a C^*-algebra. In this paper, we investigate pro-C^*-algebras from a categorical point of view. We study the functor (-)_b that assigns to a pro-C^*-algebra the C^*-algebra of its bounded elements, which is the dual of the Stone-Čech-compactification. We show that (-)_b is a coreflector, and it preserves exact sequences. A generalization of the Gelfand-duality for commutative unital pro-C^*-algebras is also presented.
description: v2 (accepted)
Operator ordering and Classical soliton path in Two-dimensional N=2 supersymmetry with Kahler potential
Creators: name: Motoyui, Nobuyuki
name: Yamada, Mitsuru
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We investigate a 2-dimensional N=2 supersymmetric model which consists of n chiral superfields with Kahler potential. When we define quantum observables, we are always plagued by operator ordering problem. Among various ways to fix the operator order, we rely upon the supersymmetry. We demonstrate that the correct operator order is given by requiring the super Poincare algebra by carrying out the canonical Dirac bracket quantization. This is shown to be also true when the supersymmetry algebra has a central extension by the presence of topological soliton. It is also shown that the path of soliton is a straight line in the complex plane of superpotential W and triangular mass inequality holds. And a half of supersymmetry is broken by the presence of soliton.
description: 13 pages, typos corrected
A variant of the tandem duplication - random loss model of genome rearrangement
Creators: name: Bouvel, Mathilde
name: Rossin, Dominique
Publisher: name: arXiv
Year: 2008
Subjects: subject: Combinatorics (math.CO)
subject: Genomics (q-bio.GN)
subject: FOS: Mathematics
subject: FOS: Biological sciences

description: In Soda'06, Chaudhuri, Chen, Mihaescu and Rao study algorithmic properties of the tandem duplication - random loss model of genome rearrangement, well-known in evolutionary biology. In their model, the cost of one step of duplication-loss of width k is $α^k$ for $α=1$ or $α>=2 $. In this paper, we study a variant of this model, where the cost of one step of width $k$ is 1 if $k <= K$ and $\infty$ if $k > K$, for any value of the parameter $K in N$. We first show that permutations obtained after $p$ steps of width $K$ define classes of pattern-avoiding permutations. We also compute the numbers of duplication-loss steps of width $K$ necessary and sufficient to obtain any permutation of $S_n$, in the worst case and on average. In this second part, we may also consider the case $K=K(n)$, a function of the size $n$ of the permutation on which the duplication-loss operations are performed.
Virtual Identification of Essential Proteins Within the Protein Interaction Network of Yeast
Creators: name: Estrada, Ernesto
Publisher: name: arXiv
Year: 2005
Subjects: subject: Molecular Networks (q-bio.MN)
subject: FOS: Biological sciences

description: Topological analysis of large scale protein-protein interaction networks (PINs) is important for understanding the organisational and functional principles of individual proteins. The number of interactions that a protein has in a PIN has been observed to be correlated with its indispensability. Essential proteins generally have more interactions than the non-essential ones. We show here that the lethality associated with removal of a protein from the yeast proteome correlates with different centrality measures of the nodes in the PIN, such as the closeness of a protein to many other proteins, or the number of pairs of proteins which need a specific protein as an intermediary in their communications, or the participation of a protein in different protein clusters in the PIN. These measures are significantly better than random selection in identifying essential proteins in a PIN. Centrality measures based on graph spectral properties of the network, in particular the subgraph centrality, show the best performance in identifying essential proteins in the yeast PIN. Subgraph centrality gives important structural information about the role of individual proteins and permits the selection of possible targets for rational drug discovery through the identification of essential proteins in the PIN.
description: 11 pages, 3 figures
Ateek, Naim Stifan: Recht, nichts als Recht!
Creators: name: Klein, Laurentius
Publisher: name: Ökumenische Rundschau
Year: 2025

description: Ökumenische Rundschau, Bd. 41 Nr. 2 (1992): Ökumenische Rundschau, Band 41, Heft 2
Runaway electron modelling in the self-consistent core European Transport Simulator, ETS
Creators: name: Pokol, Gergo I.
name: Olasz, Soma
name: Erdos, Boglarka
name: Papp, Gergely
name: Aradi, Matyas
name: Hoppe, Mathias
name: Johnson, Thomas
name: Ferreira, Jorge
name: Coster, David
name: Peysson, Yves
name: Decker, Joan
name: Strand, Par
name: Yadikin, Dimitriy
name: Kalupin, Denis
name: Team, the EUROfusion-IM
Publisher: name: arXiv
Year: 2020
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: Relativistic runaway electrons are a major concern in tokamaks. The European framework for Integrated Modelling (EU-IM), facilitates the integration of different plasma simulation tools by providing a standard data structure for communication that enables relatively easy integration of different physics codes. A three-level modelling approach was adopted for runaway electron simulations within the EU-IM. Recently, a number of runaway electron modelling modules have been integrated into this framework. The first level of modelling (Runaway Indicator) is limited to the indication if runaway electron generation is possible or likely. The second level (Runaway Fluid) adopts an approach similar to e.g. the GO code, using analytical formulas to estimate changes in the runaway electron current density. The third level is based on the solution of the electron kinetics. One such code is LUKE that can handle the toroidicity-induced effects by solving the bounce-averaged Fokker-Planck equation. Another approach is used in NORSE, which features a fully nonlinear collision operator that makes it capable of simulating major changes in the electron distribution, for example slide-away. Both codes handle the effect of radiation on the runaway distribution. These runaway-electron modelling codes are in different stages of integration into the EU-IM infrastructure, and into the European Transport Simulator (ETS), which is a fully capable modular 1.5D core transport simulator. ETS with Runaway Fluid was benchmarked to the GO code implementing similar physics. Coherent integration of kinetic solvers requires more effort on the coupling, especially regarding the definition of the boundary between runaway and thermal populations, and on consistent calculation of resistivity. Some of these issues are discussed.
Ecosystem effects on harvested populations : lower trophic level dynamics in the northeast pacific and its implications on sockeye salmon (oncorhynchus nerka) survival
Creators: name: Baumann, Michael
Publisher: name: University of British Columbia
Year: 2009

description: Almost all epipelagic fish species in the Northeast Pacific show an increase in population size between the late 1950s and the 1980s. The complexity of pelagic ecosystems makes speculations on the causes of these increases easy to justify, and thus various conjectures on the chain of events leading to increased fish survival have been put forward. In this thesis I try to explain the variability in cohort survival, abundance and distribution of sockeye salmon (Oncorhynchus nerka) - the fish species that has experienced the largest increase in abundance and biomass of all epipelagic fish species in the Northeast Pacific between the late 1950s and the 1980s - by ecosystem effects. I assumed that sockeye salmon total survival rate is largely determined in early marine life due to exposure to predators, which is set by the time at risk of predation, itself a function of sockeye prey, i.e. mesozooplankton, abundance. I then developed two simple food chain models with three and four trophic levels, respectively, which include lower trophic level dynamics but not fish itself. Both population models were calibrated and tested for two locations in the Northeast Pacific through mean field simulations driven by abiotic environmental forcings. Using a 4-hour time step from 1950 to 1990, both calibrated population models were then run as spatially-explicit simulations with a resolution of one degree latitude and longitude for the whole area of the Northeast Pacific, a total of 1240 open ocean fields. To assess the relative importance of biological processes versus physical advection both population models were simulated with and without surface currents. I have tried to design the best models within reason utilizing the best information on environmental forcings and biological processes available at the time. Simulation results do not suggest a clear linkage between prey density in the oceanic environment and sockeye salmon cohort survival. However, there are two fundamental lessons to be learned from this modeling exercise: First, categorization of ecosystem components into trophic levels with no regard of the many life history strategies is one of the worst aggregation errors in ecology, one that implicitly includes errors of hierarchical organization as well as of spatio-temporal stability. And second, the complexity of ecosystems will always make results from trophodynamic simulations interpretable, even if these results bear no relationship to the natural system.
Electronic properties of metal-induced gap states formed at alkali-halide/metal interfaces
Creators: name: Kiguchi, Manabu
name: Yoshikawa, Genki
name: Ikeda, Susumu
name: Saiki, Koichiro
Publisher: name: arXiv
Year: 2005
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The spatial distribution and site- distribution of metal induced gap states (MIGS) are studied by thickness dependent near edge x-ray absorption fine structure (NEXAFS) and comparing the cation and anion edge NEXAFS. The thickness dependent NEXAFS shows that the decay length of MIGS depends on rather an alkali halide than a metal, and it is larger for alkali halides with smaller band gap energy. By comparing the Cl edge and K edge NEXAFS for KCl/Cu(001), MIGS are found to be states localizing at anion sites.
description: 4 pages, to be published in Phys. Rev. B
Lexical and semantic elicitation: Nouns and bare noun interpretation
Creators: name: Kipkoech, Linus
name: Bossi, Madeline
Publisher: name: California Language Archive, University of California, Berkeley
Year: 2021
Subjects: subject: sgc

description: One .mp4 file and one .pdf file. Elicitation of various nouns in search of epistemic indefinites. Elicitation of singular count nouns and their various interpretations (e.g. generic, existential, definite).
Bright electrically controllable quantum-dot-molecule devices fabricated by in-situ electron-beam lithography
Creators: name: Schall, Johannes
name: Deconinck, Marielle
name: Bart, Nikolai
name: Florian, Matthias
name: von Helversen, Martin
name: Dangel, Christian
name: Schmidt, Ronny
name: Bremer, Lucas
name: Bopp, Frederik
name: Hüllen, Isabell
name: Gies, Christopher
name: Reuter, Dirk
name: Wieck, Andreas D.
name: Rodt, Sven
name: Finley, Jonathan J.
name: Jahnke, Frank
name: Ludwig, Arne
name: Reitzenstein, Stephan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: Optics (physics.optics)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Self-organized semiconductor quantum dots represent almost ideal two-level systems, which have strong potential to applications in photonic quantum technologies. For instance, they can act as emitters in close-to-ideal quantum light sources. Coupled quantum dot systems with significantly increased functionality are potentially of even stronger interest since they can be used to host ultra-stable singlet-triplet spin qubits for efficient spin-photon interfaces and for a deterministic photonic 2D cluster-state generation. We realize an advanced quantum dot molecule (QDM) device and demonstrate excellent optical properties. The device includes electrically controllable QDMs based on stacked quantum dots in a pin-diode structure. The QDMs are deterministically integrated into a photonic structure with a circular Bragg grating using in-situ electron beam lithography. We measure a photon extraction efficiency of up to (24$\pm$4)% in good agreement with numerical simulations. The coupling character of the QDMs is clearly demonstrated by bias voltage dependent spectroscopy that also controls the orbital couplings of the QDMs and their charge state in quantitative agreement with theory. The QDM devices show excellent single-photon emission properties with a multi-photon suppression of $g^{(2)}(0) = (3.9 \pm 0.5) \cdot 10^{-3}$. These metrics make the developed QDM devices attractive building blocks for use in future photonic quantum networks using advanced nanophotonic hardware.
Sweeping from the superfluid to Mott phase in the Bose-Hubbard model
Creators: name: Schützhold, Ralf
name: Uhlmann, Michael
name: Xu, Yan
name: Fischer, Uwe R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We study the sweep through the quantum phase transition from the superfluid to the Mott state for the Bose-Hubbard model with a time-dependent tunneling rate $J(t)$. In the experimentally relevant case of exponential decay, $J(t)\propto e^{-γt}$, an adapted mean-field expansion for large fillings $n$ yields a scaling solution for the fluctuations. This enables us to analytically calculate the evolution of the number and phase variations (on-site) and correlations (off-site) for slow ($γ\llμ$), intermediate, and fast (non-adiabatic $γ\ggμ$) sweeps, where $μ$ is the chemical potential. Finally, we derive the dynamical decay of the off-diagonal long-range order as well as the temporal shrinkage of the superfluid fraction in a persistent ring-current setup.
description: 4 pages of RevTex4, 1 figure; to appear in Physical Review Letters
Riemann Surfaces of genus g with an automorphism of order p prime and p>g
Creators: name: Urzua, Giancarlo
Publisher: name: arXiv
Year: 2005
Subjects: subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics
subject: 14H55 (primary) 14H37, 14H15 (secondary)

description: The present work completes the classification of the compact Riemann surfaces of genus g with an analytic automorphism of order p (prime number) and p > g. More precisely, we construct a parameteriza- tion space for them, we compute their groups of uniformization and we compute their full automorphism groups. Also, we give affine equations for special cases and some implications on the components of the singular locus of the moduli space of smooth curves of genus g.
description: 28 pages, 5 figures
Many-Body Dynamics and Exciton Formation Studied by Time-Resolved Photoluminescence
Creators: name: Hoyer, W.
name: Ell, C.
name: Kira, M.
name: Koch, S. W.
name: Chatterjee, S.
name: Mosor, S.
name: Khitrova, G.
name: Gibbs, H. M.
name: Stolz, H.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: 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.
description: 11 pages, 5 figures
Pentaquarks in the medium in the quark-meson coupling model
Creators: name: Panda, P. K.
name: Providência, C.
name: Menezes, D. P.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We calculate the properties of the pentaquarks $Θ^+$ and $Ξ^{--,0}$ in symmetric nuclear matter using the quark meson coupling model (QMC). The stability of the $Θ^+$ in the medium with respect to the channel $Θ^+\to NK^+$ is discussed.
description: 6 pages, 5 figures, revtex
The many body problem in relativistic quantum mechanics
Creators: name: Moshinsky, Marcos
name: Nikitin, Anatoly
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We discusse a relativistic Hamiltonian for an n-body problem in which all the masses are equal and all spins take value 1/2. In the frame of reference in which the total momentum $vP=0$, the Foldy-Wouthuysen transformation is applies and the positive energy part of the Hamiltonian is separated. The Hamiltonian with unharmonic oscillator potential is applied to describe mass differences for charmonium and bottonium states.
Threshold Resistance in the DC Josephson Effect
Creators: name: Kim, Yong-Jihn
Publisher: name: arXiv
Year: 2006
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We show that SIS Josephson junctions have a threshold resistance, above which the Josephson coupling and the supercurrents become extremely small, due to the shrinking of the Cooper pair size during the Josephson tunneling. Accordingly, the threshold resistance is smaller for higher Tc superconductors with small Cooper pair size and for the insulating barrier with higher resistance. This understanding agrees with the observations in SIS junctions of low Tc superconductors, such as Sn, Pb, and Nb. For MgB2 it explains why the big gap does not show the supercurrents, unlike the small gap. Furthermore, it is consistent with the fact that high Tc cuprates show the Josephson effects only for SNS type junctions, including the intrinsic Josephson effects.
description: Proceedings of LT24 Conference, 2 pages, 1 figure. For more information, please see http://www.superconductivity.us (1 RA position available)
Software Libraries and Their Reuse: Entropy, Kolmogorov Complexity, and Zipf's Law
Creators: name: Veldhuizen, Todd L.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Software Engineering (cs.SE)
subject: Information Theory (cs.IT)
subject: Programming Languages (cs.PL)
subject: FOS: Computer and information sciences
subject: D.2.8; E.4; D.2.13

description: We analyze software reuse from the perspective of information theory and Kolmogorov complexity, assessing our ability to ``compress'' programs by expressing them in terms of software components reused from libraries. A common theme in the software reuse literature is that if we can only get the right environment in place-- the right tools, the right generalizations, economic incentives, a ``culture of reuse'' -- then reuse of software will soar, with consequent improvements in productivity and software quality. The analysis developed in this paper paints a different picture: the extent to which software reuse can occur is an intrinsic property of a problem domain, and better tools and culture can have only marginal impact on reuse rates if the domain is inherently resistant to reuse. We define an entropy parameter $H \in [0,1]$ of problem domains that measures program diversity, and deduce from this upper bounds on code reuse and the scale of components with which we may work. For ``low entropy'' domains with $H$ near 0, programs are highly similar to one another and the domain is amenable to the Component-Based Software Engineering (CBSE) dream of programming by composing large-scale components. For problem domains with $H$ near 1, programs require substantial quantities of new code, with only a modest proportion of an application comprised of reused, small-scale components. Preliminary empirical results from Unix platforms support some of the predictions of our model.
Quantum Deformations from Toric Geometry
Creators: name: Pinansky, Samuel
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We will demonstrate how calculations in toric geometry can be used to compute quantum corrections to the relations in the chiral ring for certain gauge theories. We focus on the gauge theory of the del Pezzo 2, and derive the chiral ring relations and quantum deformations to the vacuum moduli space using Affleck-Dine-Seiberg superpotential arguments. Then we calculate the versal deformation to the corresponding toric geometry using a method due to Altmann, and show that the result is equivalent to the deformation calculated using gauge theory. In an appendix we will apply this technique to a few other examples. This is a new method for understanding the infrared dynamics of certain quiver gauge theories.
description: 30 pages, 4 figures, uses axodraw.sty, latex
Familon Model of Dark Matter
Creators: name: Burdyuzha, V.
name: Lalakulich, O.
name: Ponomarev, Yu.
name: Vereshkov, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: If the next fundamental level of matter occurs (preons) then dark matter must consist of familons containing a "hot" component from massless particles and a "cold" component from massive particles. During evolution of the Universe this dark matter was undergone to late-time relativistic phase transitions temperatures of which were different. Fluctuations created by these phase transitions have had a fractal character. In the result the structurization of dark matter (and therefore the baryon subsystem) has taken place and in the Universe some characteristic scales which have printed this phenomenon arise naturally. Familons are collective excitations of nonperturbative preon condensates which could be produced during more early relativistic phase transition. For structurization of dark matter (and baryon component) three generations of particles are necessary. The first generation of particles has produced the observed baryon world. The second and third generations have produced dark matter from particles which have appeared when symmetry among generations was spontaneously broken.
description: 12 pages
Strongly anisotropic media: the THz perspectives of left-handed materials
Creators: name: Podolskiy, Viktor A.
name: Alekseev, Leo
name: Narimanov, Evgenii E.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Optics (physics.optics)
subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: We demonstrate that non-magnetic ($μ\equiv 1$) left-handed materials can be effectively used for waveguide imaging systems. We also propose a specific THz realization of the non-magnetic left-handed material based on homogeneous, naturally-occurring media.
Josephson interferometer in a ring topology as a symmetry prove of Sr_2RuO_4
Creators: name: Asano, Y.
name: Tanaka, Y.
name: Sigrist, M.
name: Kashiwaya, S.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: The Josephson effect is theoretically studied in two types of SQUIDs consisting of $s$ wave superconductor and Sr$_2$RuO$_4$. Results show various response of the critical Josephson current to applied magnetic fields depending on the type of SQUID and on the pairing symmetries. In the case of a $p_x+ip_y$ wave symmetry, the critical current in a corner SQUID becomes an asymmetric function of magnetic fields near the critical temperatures. Our results well explain a recent experimental finding [Nelson et. al, Science \textbf{306}, 1151 (2004)]. We also discuss effects of chiral domains on the critical current.
description: 7 pages
Sparse repulsive coupling enhances synchronization in complex networks
Creators: name: Leyva, I.
name: Sendiña-Nadal, I.
name: Almendral, J. A.
name: Sanjuán, M. A. F.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: Through the last years, different strategies to enhance synchronization in complex networks have been proposed. In this Letter, we show that the synchronization in a small-world network of attractively coupled non-identical neurons is strongly improved by adding a tiny fraction of phase-repulsive couplings. By a purely topological analysis that does not depend on the dynamical model, we link the emerging dynamical behavior to the structural properties of the sparsely coupled repulsive network.
description: 4 pages, 4 figures
A unitarity analysis on the I=0 $d$ wave $ππ$ scattering amplitude
Creators: name: Wang, Jian-jun
name: Zhou, Z. Y.
name: Zheng, H. Q.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study I=0 $d$ wave $ππ$ scattering phase shift using a proper unitarization approach. It is verified that the $f_2(1270)$ resonance corresponds to a twin pole structure: one on the second sheet, another one on the third sheet. Also we find fair agreement on $f_2(1270)$ pole's mass and width between our results and the PDG values. Besides, our analysis reveals the existence of a virtual state in this channel. Its pole location is determined by fitting experimental data and it is found to be in good agreement with the prediction from chiral perturbation theory. Our analysis demonstrates that partial wave amplitudes calculated in chiral perturbation theory are reliable in the small $|s|$ region, contrary to some unitarization models.
description: replaced by the version published in JHEP 0512 (2005) 019. Especially the mistake in the title is corrected
Utilization of electromagnetic detector for selection and detection of high-frequency relic gravitational waves
Creators: name: Li, Fangyu
name: Chen, Zhenya
name: Yi, Ying
Publisher: name: arXiv
Year: 2005
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: It is shown that coupling system between fractal membranes and a Gaussian beam passing through a static magnetic field has strong selection capability for the stochastic relic gravitational wave background. The relic GW components propagating along the positive direction of the symmetrical axis of the Gaussian beam might generate an optimal electromagnetic perturbation while the perturbation produced by the relic GW components propagating along the negative and perpendicular directions to the symmetrical axis will be much less than the former.The influence of the random fluctuation of the relic GWs to such effect can be neglected and the influence of the random fluctuation of the relic GWs to such effect can be neglected.
description: 9 pages, 1 figure, 1 table
Neutron tagging of quasielastic J/psi photoproduction off nucleus in ultraperipheral heavy ion collisions at RHIC energies
Creators: name: Strikman, M.
name: Tverskoy, M.
name: Zhalov, M.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We compare the coherent and quasielastic J/psi photoproduction in the peripheral heavy ion collisions in kinematics of RHIC. Our improved estimate of the total coherent cross section is a factor of two smaller than the earlier ones. We find that the counting rate of quasielastic J/psi photoproduction tagged by neutrons emitted due to cascading of the recoiled nucleon within the residual nucleus exceeds the rate of the coherent events. We argue that measurements of this process can be used to learn about the dynamics of color dipole-nucleon interactions in nuclei in the wide effective range of energies of gamma A interactions.
description: 12 pages, 5 figures
Schrödinger representation of SU(2) Skyrmion
Creators: name: Hong, Soon-Tae
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Exploiting the SU(2) Skyrmion Lagrangian with second-class constraints associated with Lagrange multiplier and collective coordinates, we convert the second-class system into the first-class one in the Batalin-Fradkin-Tyutin embedding through introduction of the Stückelberg coordinates. In this extended phase space we construct the "canonical" quantum operator commutators of the collective coordinates and their conjugate momenta to describe the Schrödinger representation of the SU(2) Skyrmion, so that we can define isospin operators and their Casimir quantum operator and the corresponding eigenvalue equation possessing integer quantum numbers, and we can also assign via the homotopy class $π_{4}(SU(2))=Z_{2}$ half integers to the isospin quantum number for the solitons in baryon phenomenology. Different from the semiclassical quantization previously performed, we exploit the "canonical" quantization scheme in the enlarged phase space by introducing the Stückelberg coordinates, to evaluate the baryon mass spectrum having global mass shift originated from geometrical corrections due to the $S^{3}$ compact manifold involved in the topological Skyrmion. Including ghosts and anti-ghosts, we also construct Becci-Rouet-Stora-Tyutin invariant effective Lagrangian.
description: 7 pages, Taylor Memorial Lecture given at Forty Nineth Congress of the Indian Society of Theoretical and Applied Mechanics
Variable iron-line emission near the black hole of Markarian 766
Creators: name: Miller, L.
name: Turner, T. J.
name: Reeves, J. N.
name: George, I. M.
name: Porquet, D.
name: Nandra, K.
name: Dovciak, M.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the link between ionised Fe X-ray line emission and continuum emission in the bright nearby AGN, Mrk 766. A new long (433 ks) XMM-Newton observation is analysed, together with archival data from 2000 and 2001. The contribution from ionised line emission is measured and its time variations on short (5-20 ks) timescales are correlated with the continuum emission. The ionised line flux is found to be highly variable and to be strongly correlated with the continuum flux, demonstrating an origin for the ionised line emission that is co-located with the continuum emission. Most likely the emission is ionised reflection from the accretion disc within a few A.U. of the central black hole, and its detection marks the first time that such an origin has been identified other than by fitting to spectral line profiles. Future observations may be able to measure a time lag and hence achieve reverberation mapping of AGN at X-ray energies.
description: Accepted for publication, Astronomy and Astrophysics letters
Direct evidence of the self-compression of injected electron-hole plasma in silicon
Creators: name: Altukhov, Pavel
name: Kuzminov, Evgenii
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A surface distribution of the electroluminescence intensity of silicon p-n light emitting diodes is obtained under space scanning experiments at room temperature. An emitting surface of the diodes, represented by a few small bright emitting dots and a weakly emitting area outside the dots, serves as a direct evidence of the self-compression of injected electron-hole plasma in silicon. The plasma self-compression explains concentration of injected carriers into one or a few strongly emitting plasma drops.
description: 3 pages, 2 figures, published in Physica Status Solidi (b)
(Sub)stellar companions shape the winds of evolved stars
Creators: name: Decin, L.
name: Montargès, M.
name: Richards, A. M. S.
name: Gottlieb, C. A.
name: Homan, W.
name: McDonald, I.
name: Mellah, I. El
name: Danilovich, T.
name: Wallström, S. H. J.
name: Zijlstra, A.
name: Baudry, A.
name: Bolte, J.
name: Cannon, E.
name: De Beck, E.
name: De Ceuster, F.
name: de Koter, A.
name: De Ridder, J.
name: Etoka, S.
name: Gobrecht, D.
name: Gray, M.
name: Herpin, F.
name: Jeste, M.
name: Lagadec, E.
name: Kervella, P.
name: Khouri, T.
name: Menten, K.
name: Millar, T. J.
name: Müller, H. S. P.
name: Plane, J. M. C.
name: Sahai, R.
name: Sana, H.
name: Van de Sande, M.
name: Waters, L. B. F. M.
name: Wong, K. T
name: Yates, J.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Binary interactions dominate the evolution of massive stars, but their role is less clear for low- and intermediate-mass stars. The evolution of a spherical wind from an asymptotic giant branch (AGB) star into a nonspherical planetary nebula (PN) could be due to binary interactions. We observed a sample of AGB stars with the Atacama Large Millimeter/submillimeter Array (ALMA) and found that their winds exhibit distinct nonspherical geometries with morphological similarities to planetary nebulae (PNe). We infer that the same physics shapes both AGB winds and PNe; additionally, the morphology and AGB mass-loss rate are correlated. These characteristics can be explained by binary interaction. We propose an evolutionary scenario for AGB morphologies that is consistent with observed phenomena in AGB stars and PNe.
description: 19 pages main journal, 97 pages Supplementary Information
Resolution to the B -> pi K puzzle
Creators: name: Li, Hsiang-nan
name: Mishima, Satoshi
name: Sanda, A. I.
Publisher: name: arXiv
Year: 2005
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We calculate the important next-to-leading-order contributions to the B -> pi K, pi pi decays from the vertex corrections, the quark loops, and the magnetic penguins in the perturbative QCD approach. It is found that the latter two reduce the leading-order penguin amplitudes by about 10%, and modify only the B -> pi K branching ratios. The main effect of the vertex corrections is to increase the small color-suppressed tree amplitude by a factor of 3, which then resolves the large difference between the direct CP asymmetries of the B^0 -> pi^\mp K^\pm and B^\pm -> pi^0 K^\pm modes. The puzzle from the large B^0 -> pi^0 pi^0 branching ratio still remains.
description: 26 pages, 19 figures, REVTeX4; minor corrections, references added, version to appear in Phys. Rev. D
Non-equilibrium Magnetic Properties of Single Crystalline La0.7Ca0.3CoO3
Creators: name: Kundu, Asish K.
name: Nordblad, P.
name: Rao, C. N. R.
Publisher: name: arXiv
Year: 2005
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Magnetic and electric properties of a single crystal of La0.7Ca0.3CoO3 have been experimentally studied. The system attains a ferromagnetic spontaneous moment below 170 K and exhibits a re-entrant spin-glass phase below 100 K. In the ordered and the re-entrant phases, the low field magnetic properties are strongly direction dependent, showing considerably higher magnetization values perpendicular than parallel to the c-axis. Magnetic relaxation experiments show that both the ferromagnetic and the re-entrant spin-glass phases are non-equilibrium states, where the system exhibits magnetic aging characteristic of spin-glasses and disordered and frustrated ferromagnets.
description: 21 pages including figures
Ionic liquid gating induced two superconductor-insulator phase transitions in spinel oxide Li$_{1 \pm x}$Ti$_2$O$_{4-δ}$
Creators: name: Wei, Zhongxu
name: Li, Qian
name: Gong, Ben-Chao
name: Wei, Xinjian
name: Hu, Wei
name: Ni, Zhuang
name: He, Ge
name: Qin, Mingyang
name: Kusmartseva, Anna
name: Kusmartsev, Fedor V.
name: Yuan, Jie
name: Zhu, Beiyi
name: Chen, Qihong
name: Chen, Jian-Hao
name: Liu, Kai
name: Jin, Kui
Publisher: name: arXiv
Year: 2021
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: The associations between emergent physical phenomena (e.g., superconductivity) and orbital, charge, and spin degrees of freedom of $3d$ electrons are intriguing in transition metal compounds. Here, we successfully manipulate the superconductivity of spinel oxide Li$_{1\pm x}$Ti$_2$O$_{4-δ}$ (LTO) by ionic liquid gating. A dome-shaped superconducting phase diagram is established, where two insulating phases are disclosed both in heavily electron-doping and hole-doping regions. The superconductor-insulator transition (SIT) in the hole-doping region can be attributed to the loss of Ti valence electrons. In the electron-doping region, LTO exhibits an unexpected SIT instead of a metallic behavior despite an increase in carrier density. Furthermore, a thermal hysteresis is observed in the normal state resistance curve, suggesting a first-order phase transition. We speculate that the SIT and the thermal hysteresis stem from the enhanced $3d$ electron correlations and the formation of orbital ordering by comparing the transport and structural results of LTO with the other spinel oxide superconductor MgTi$_2$O$_4$, as well as analysing the electronic structure by first-principles calculations. Further comprehension of the detailed interplay between superconductivity and orbital ordering would contribute to the revealing of unconventional superconducting pairing mechanism.
description: 6 pages, 4 figures
Urca Nuclide Production in Type-I X-ray Bursts and Implications for Nuclear Physics Studies
Creators: name: Merz, Grant
name: Meisel, Zach
Publisher: name: arXiv
Year: 2020
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: The thermal structure of accreting neutron stars is affected by the presence of urca nuclei in the neutron star crust. Nuclear isobars harboring urca nuclides can be produced in the ashes of Type I X-ray bursts, but the details of their production have not yet been explored. Using the code {\tt MESA}, we investigate urca nuclide production in a one-dimensional model of Type I X-ray bursts using astrophysical conditions thought to resemble the source GS 1826-24. We find that high-mass ($A\geq55$) urca nuclei are primarily produced late in the X-ray burst, during hydrogen-burning freeze-out that corresponds to the tail of the burst light curve. The $\sim0.4$--0.6~GK temperature relevant for nucleosynthesis of these urca nuclides is much lower than the $\sim1$~GK temperature most relevant for X-ray burst light curve impacts by nuclear reaction rates involving high-mass nuclides. The latter temperature is often assumed for nuclear physics studies. Therefore, our findings alter the excitation energy range of interest in compound nuclei for nuclear physics studies of urca nuclide production. We demonstrate that for some cases this will need to be considered in planning for nuclear physics experiments. Additionally, we show that the lower temperature range for urca nuclide production explains why variations of some nuclear reaction rates in model calculations impacts the burst light curve but not local features of the burst ashes.
description: Accepted to MNRAS
Optimization of Biomimetic Oyster Cement for Commercial Applications
Creators: name: Scott, Collin Ryder
Publisher: name: Purdue University Graduate School
Year: 2025
Subjects: classificationCode: 401609
subject: Polymers and plastics
classificationCode: 340501
subject: Free radical chemistry
classificationCode: 401605
subject: Functional materials

description: Polymer modified cement (PMC) is a composite material formed by incorporating polymers into cement. This improves various mechanical properties of cement, such as its flexibility, adhesion, and toughness, providing solutions to a wide range of engineering challenges. Looking to nature for inspiration, oysters produce biological cement to build extensive reef communities underwater. Previous studies have shown this cement is composed of 12% organics (peptides, carbohydrates, and lipids) and 85% calcium carbonate (CaCO3), with the remainder being water. The organic matrix is mostly uncharacterized, with previous studies showing signs of phosphate-based moieties. This thesis applies oyster cement chemistry to commercial cement, to create a biomimetic PMC system that uses phosphate-functionalized polymers to increase adhesion and compression strength. This polymer and CaCO3 system is optimized through a series of ladder studies, tested against commercial benchmarks, and eventually incorporated into commercial mortar mix. This leads to a 300% increase in compressive strength and a 700% increase in adhesive strength on wetted substrates.This thesis also includes the preliminary results of characterization of the chemical adhesive of poison ivy (Toxicodendron radicans) aerial rootlets using histological staining methods and fluorescence microscopy. Although unrelated to the main subject of this thesis, the Wilker lab had never performed tests and staining procedures for the characterizations described. This thesis memorialized the work performed for reference to future students in the lab who will perform similar testing.