cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Numerical evaluation of the Casimir interaction between cylinders
Creators: name: Lombardo, F. C.
name: Mazzitelli, F. D.
name: Villar, P. I.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We numerically evaluate the Casimir interaction energy for configurations involving two perfectly conducting eccentric cylinders and a cylinder in front of a plane. We consider in detail several special cases. For quasi-concentric cylinders, we analyze the convergence of a perturbative evaluation based on sparse matrices. For concentric cylinders, we obtain analytically the corrections to the proximity force approximation up to second order, and we present an improved numerical procedure to evaluate the interaction energy at very small distances. Finally, we consider the configuration of a cylinder in front of a plane. We first show numerically that, in the appropriate limit, the Casimir energy for this configuration can be obtained from that of two eccentric cylinders. Then we compute the interaction energy at small distances, and compare the numerical results with the analytic predictions for the first order corrections to the proximity force approximation.
description: 11 pages, 13 figures. Minor changes, version to appear in Phys. Rev. D
U.S. Agricultural Exports Reached All-time High of $6.1 Billion in Fiscal Year 1963-64
Creators: name: Ontz, Robert L.
name: Rahe, Dewain H.
name: Ontz, Robert L.
name: Rahe, Dewain H.
Publisher: name: Unknown
Year: 1964
Subjects: Agricultural and Food Policy
International Relations/Trade

description: Excerpts from the report: U.S. agricultural exports are estimated at a record $6,115 million in fiscal year 1963-64, up 20 percent from the $5,078 million for the previous fiscal year. The figure for 1963-64 includes actual exports of $5,616 million for July-May and an estimate of $499 million for June. Principal increases occurred in wheat and flour, cotton, feed grains, soybeans, rice, tobacco, tallow, lard, dairy products, poultry products, and meat. Small declines took place for fruits, vegetables, and vegetable oils. Agricultural exports in 1963-64 were $2 billion larger than agricultural imports. This is the largest agricultural export balance on record in the past half century. The balance of trade for the past several years has been highly favorable, reflecting the pronounced upward trend in agricultural exports.
description: Reprinted from Foreign Agricultural Trade of the United States August 1964
Algebraic charge liquids
Creators: name: Kaul, Ribhu K.
name: Kim, Yong Baek
name: Sachdev, Subir
name: Senthil, T.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: High temperature superconductivity emerges in the cuprate compounds upon changing the electron density of an insulator in which the electron spins are antiferromagnetically ordered. A key characteristic of the superconductor is that electrons can be extracted from them at zero energy only if their momenta take one of four specific values (the `nodal points'). A central enigma has been the evolution of the zero energy electrons in the metallic state between the antiferromagnet and the superconductor, and recent experiments yield apparently contradictory results. The oscillation of the resistance in this metal as a function of magnetic field indicate that the zero energy electrons carry momenta which lie on elliptical `Fermi pockets', while ejection of electrons by high intensity light indicates that the zero energy electrons have momenta only along arc-like regions. We present a theory of new states of matter, which we call `algebraic charge liquids', which arise naturally between the antiferromagnet and the superconductor, and reconcile these observations. Our theory also explains a puzzling dependence of the density of superconducting electrons on the total electron density, and makes a number of unique predictions for future experiments.
description: 6+8 pages, 2 figures; (v2) Rewritten for broader accessibility; (v3) corrected numerical error in Eq. (5)
Exploring the disc/jet interaction in the radio-loud quasar 4C +74.26 with Suzaku
Creators: name: Larsson, J.
name: Fabian, A. C.
name: Ballantyne, D. R.
name: Miniutti, G.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We report on a 90 ks Suzaku observation of the radio-loud quasar 4C +74.26. The source was observed in its highest flux state to date, and we find that it brightened by about 20 per cent during the observation. We see evidence of spectral hardening as the count rate increases and also find that the rms variability increases with energy up to about 4 keV. We clearly detect a broadened Fe line but conclude that it does not require any emission from inside about 50 r_g, although a much smaller inner radius cannot be ruled out. The large inner radius of our best fit implies that the inner disc is either missing or not strongly illuminated. We suggest that the latter scenario may occur if the power-law source is located high above the disc, or if the emission is beamed away from the disc.
description: 11 pages, 9 figures. Accepted for publication in MNRAS
Self-similar dilatation structures and automata
Creators: name: Buliga, Marius
Publisher: name: arXiv
Year: 2007
Subjects: subject: Metric Geometry (math.MG)
subject: Discrete Mathematics (cs.DM)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: 22A30; 05C12; 68Q45

description: We show that on the boundary of the dyadic tree, any self-similar dilatation structure induces a web of interacting automata. This is a short version, for publication, of the paper arXiv:math/0612509v2
Black Hole Constraints on Varying Fundamental Constants
Creators: name: MacGibbon, Jane H
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Here we apply the Generalized Second Law of Thermodynamics and derive upper limits on the variation in the fundamental constants. The maximum variation in the electronic charge permitted for black holes accreting and emitting in the present cosmic microwave background corresponds to a variation in the fine structure constant of ((Delta alpha) / alpha) ~ 2 x 10^-23 per second. This value matches the variation measured by Webb et al. using absorption lines in the spectra of distant quasars and suggests the variation mechanism may be a coupling between the electron and the cosmic photon background.
description: 5 pages, published version
Elementary Charge Transfer Processes in Mesoscopic Conductors
Creators: name: Vanevic, Mihajlo
name: Nazarov, Yuli V.
name: Belzig, Wolfgang
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We determine charge transfer statistics in a quantum conductor driven by a time-dependent voltage and identify the elementary transport processes. At zero temperature unidirectional and bidirectional single charge transfers occur. The unidirectional processes involve electrons injected from the source terminal due to excess dc bias voltage. The bidirectional processes involve electron-hole pairs created by time-dependent voltage bias. This interpretation is further supported by the charge transfer statistics in a multiterminal beam splitter geometry in which injected electrons and holes can be partitioned into different outgoing terminals. The probabilities of elementary processes can be probed by noise measurements: the unidirectional processes set the dc noise level while bidirectional ones give rise to the excess noise. For ac voltage drive, the noise oscillates with increasing the driving amplitude. The decomposition of the noise into the contributions of elementary processes identifies the origin of these oscillations: the number of electron-hole pairs generated per cycle increases with increasing the amplitude. The decomposition of the noise into elementary processes is studied for different time-dependent voltages. The method we use is also suitable for systematic calculation of higher-order current correlators at finite temperature. We obtain current noise power and the third cumulant in the presence of time-dependent voltage drive. The charge transfer statistics at finite temperature can be interpreted in terms of multiple charge transfers with probabilities which depend on energy and temperature.
description: 15 pages, 9 figures
Understanding AGN through variability: pleasures and pains!
Creators: name: Paolillo, Maurizio
Publisher: name: Zenodo
Year: 2024
Subjects: AGN
Variability
Supermassive Black Holes
Active nuclei

description: I review the current knowledge of (radio-quiet) AGN continuum variability in X-ray and opticalbands in terms of methodologies and application to local and high redshift sources, it’sability to constrain the physics of the accretion process and the size of the AGNcomponents. I will finally highlight the results and expectations from timing studiesin large sky surveys.
Large power spectrum and primordial black holes in the effective theory of inflation
Creators: name: Ballesteros, Guillermo
name: Céspedes, Sebastián
name: Santoni, Luca
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the generation of a large power spectrum, necessary for primordial black hole formation, within the effective theory of single-field inflation. The mechanisms we consider include a transition into a ghost-inflation-like phase and scenarios where an exponentially growing mode is temporarily turned on. In the cases we discuss, the enhancement in the power spectrum results from either a swift change in some effective coupling or a modification of the dispersion relation for the perturbations, while the background evolution remains unchanged and approximately de Sitter throughout inflation. The robustness of the results is guaranteed thanks to a weakly broken galileon symmetry, which protects the effective couplings against large quantum corrections. We discuss how the enhancement of the power spectrum is related to the energy scale of the operators with weakly broken galileon invariance, and study the limits imposed by strong coupling and the validity of the perturbative expansion.
description: Some sentences rephrased for clarity
Frustration Induced Quantum Phases in Mixed Spin Chain with Frustrated Side Chains
Creators: name: Hida, Kazuo
name: Takano, Ken'ichi
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A mixed Heisenberg spin chain with frustrated side chains is investigated by numerical and perturbational calculations. A frustration-induced quantum partially polarized ferrimagnetic phase and a nonmagnetic spin quadrupolar phase are found adjacent to the conventional Lieb-Mattis type ferrimagnetic phase or the nonmagnetic singlet cluster solid phases. The partially polarized ferrimagnetic phase has an incommensurate spin structure. Similar structures are commonly found in other frustration-induced partially polarized ferrimagnetic phases. Numerical results also suggest a series of almost critical nonmagnetic ground states in a highly frustrated regime if the side chain spins weakly couple to the main chain.
description: 10 pages, 18 figures
Exploration of interacting dynamical dark energy model with interaction term including the equation-of-state parameter: alleviation of the $H_{0}$ tension
Creators: name: Guo, Rui-Yun
name: Feng, Lu
name: Yao, Tian-Ying
name: Chen, Xing-Yu
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We explore a scenario of interacting dynamical dark energy model with the interaction term $Q$ including the varying equation-of-state parameter $w$. Using the data combination of the cosmic microwave background, the baryon acoustic oscillation, and the type Ia supernovae, to global fit the interacting dynamical dark energy model, we find that adding a factor of the varying $w$ in the function of $Q$ can change correlations between the coupling constant $β$ and other parameters, and then has a huge impact on the fitting result of $β$. In this model, the fitting value of $H_{0}$ is lower at the $3.54 σ$ level than the direct measurement value of $H_{0}$ . Comparing to the case of interacting dynamical dark energy model with $Q$ excluding $w$, the model with $Q$ including the constant $w$ is more favored by the current mainstream observation. To obtain higher fitting values of $H_{0}$ and narrow the discrepancy of $H_{0}$ between different observations, additional parameters including the effective number of relativistic species, the total neutrino mass, and massive sterile neutrinos are considered in the interacting dynamical dark energy cosmology. We find that the $H_{0}$ tension can be further reduced in these models, but is still at the about $3 σ$ level.
description: 14 pages, 4 figures
Anomalous dynamical large deviations of local empirical densities and activities in the pure and in the random kinetically-constrained East Model
Creators: name: Monthus, Cecile
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The East model is the simplest one-dimensional kinetically-constrained model of $N$ spins with a trivial equilibrium that displays anomalously large spatio-temporal fluctuations, with characteristic "space-time bubbles" in trajectory space, and with a discontinuity at the origin for the first derivative of the scaled cumulant generating function of the total activity. These striking dynamical properties are revisited via the large deviations at various levels for the relevant local empirical densities and activities that only involve two consecutive spins. This framework allows to characterize their anomalous rate functions and to analyze the consequences for all the time-additive observables that can be reconstructed from them, both for the pure and for the random East model. These singularities in dynamical large deviations properties disappear when the hard-constraint of the East model is replaced by the soft constraint.
description: v3=final version (40 pages)
CII*/CII ratio in high-redshift DLAs: ISM phase separation drives the observed bimodality of [CII] cooling rates
Creators: name: Balashev, S. A.
name: Telikova, K. N.
name: Noterdaeme, P.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We discuss observations of CII*/CII ratios and cooling rates due to [CII]$\,$158$μ$m emission in high-redshift intervening damped Lyman-$α$ systems towards quasars. We show that the observed bimodality in the CII cooling rates actually reflects a bimodality in the CII*/CII-metallicity plane that can be naturally explained by phase segregation of the neutral medium, without invoking differences in star-formation scenarios. Assuming realistic distributions of the physical parameters to calculate the phase diagrams, we also reproduce qualitatively the metallicity dependence of this bimodality. We emphasize that high-z DLAs mostly probe low-metallicity gas ($Z\lesssim 0.1 Z_{\odot}$), where heating is dominated by cosmic rays (and/or turbulence), and not by photoelectric heating. Therefore even if the gas of DLA is predominantly cold (where the cooling is dominated by [CII]), the excitation of CII can be used to derive the cosmic ray ionization rate (and/or turbulent heating), but not the UV field, as was previously considered. Alternatively, if the gas in DLA is predominantly warm, CII*/CII can be used to constrain its number density. Finally, we also discuss the importance of the ionized medium, which, if also present along the line of sight, can significantly increase the average CII*/CII ratio.
description: 6 pages, 4 figures, Accepted for publication in MNRAS Letters
Finding the brightest QSOs with QUBRICS
Creators: name: CRISTIANI, Stefano
Publisher: name: Zenodo
Year: 2024

description: The QUBRICS (QUasars as BRIght beacons for Cosmology in the Southern hemisphere) survey is designed to assemble a sample of the brightest quasars with 𝑧>∼ 2.5, observable with facilities in the Southern Hemisphere. The challenge of finding high-redshift QSOs is two-fold:  firstly, discriminating QSOs from stars, galaxies and other sources, and, subsequently, estimating a redshift in order to discard low redshift candidates. The strategy devised to address this issue involves the creation of an efficient database, used to train both classification and regression models. QUBRICS takes advantage of Machine Learning methodologies tailored for the extraction of the rare needles-QSOs from the haystack of optical and IR wide-field surveys, optimizing different approaches to maximize completeness or success rates according to specific scientific goals. This talk outlines the lessons learned in the field of machine learning, which hold potential for application across diverse domains beyond astrophysics Furthermore, it presents new results about the evolution of the QSO/AGN luminosity function (in conjunction with recent JWST observations) and the AGN contribution to the cosmic UV background and HI and HeII reionization. Another goal of the QUBRICS project is to take advantage of the newly identified QSOs by using them as probes for the intervening medium.  A Golden Sample of seven quasars is presented that makes it possible to carry out the Sandage test of the cosmological redshift drift using the ANDES spectrograph at the 39m ELT with a significant reduction of observing time with respect to previous estimates. Pilot observations have already been initiated with the ESPRESSO spectrograph on the two brightest QSOs that will improve current bounds by an order of magnitude and provide a complete end-to-end proof of concept for the ANDES/ELT experiment as well as a (modest) zeroth epoch.
Number of the QCD critical points with neutral color superconductivity
Creators: name: Zhang, Zhao
name: Fukushima, Kenji
name: Kunihiro, Teiji
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We investigate the effect of the electric-charge neutrality in $β$ equilibrium on the chiral phase transition by solving the chiral and diquark condensates in the two-flavor Nambu--Jona-Lasinio model. We demonstrate that the electric-charge neutrality plays a similar role as the repulsive vector interaction; they both weaken the first-order chiral phase transition in the high-density and low-temperature region. The first-order chiral phase transition is not affected, however, at finite temperatures where the diquark condensate melts. In this way the chiral phase transition could be second-order at intermediate temperatures if the diquark effects overwhelm the chiral dynamics, while the first-order transition may survive at lower and higher temperatures. The number of the critical points appearing on the phase diagram can vary from zero to three, which depends on the relative strength of the chiral and diquark couplings. We systematically study the possibility of the phase structure with multiple QCD critical points and evaluate the Meissner screening mass to confirm that our conclusion is not overturned by chromomagnetic instability.
description: 14 pages, 10 figures. Version for PRD
Effects of Selection and Covariance on X-ray Scaling Relations of Galaxy Clusters
Creators: name: Nord, B.
name: Stanek, R.
name: Rasia, E.
name: Evrard, A. E.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We explore how the behavior of galaxy cluster scaling relations are affected by flux-limited selection biases and intrinsic covariance among observable properties. Our models presume log-normal covariance between luminosity (L) and temperature (T) at fixed mass (M), centered on evolving, power-law mean relations as a function of host halo mass. Selection can mimic evolution; the \lm and \lt relations from shallow X-ray flux-limited samples will deviate from mass-limited expectations at nearly all scales while the relations from deep surveys ($10^{-14} \cgsflux$) become complete, and therefore unbiased, at masses above $\sims 2 \times 10^{14} \hinv \msol$. We derive expressions for low-order moments of the luminosity distribution at fixed temperature, and show that the slope and scatter of the \lt relation observed in flux-limited samples is sensitive to the assumed \lt correlation coefficient. In addition, \lt covariance affects the redshift behavior of halo counts and mean luminosity in a manner that is nearly degenerate with intrinsic population evolution.
description: 5pages, 4 Figures, Submitted to MNRAS
Discovery of Bragg confined hybrid modes with high Q-factor in a hollow dielectric resonator
Creators: name: Floch, Jean-Michel le
name: Tobar, Michael E.
name: Mouneyrac, David
name: Cros, Dominique
name: Krupka, Jerzy
Publisher: name: arXiv
Year: 2007
Subjects: subject: Optics (physics.optics)
subject: Instrumentation and Detectors (physics.ins-det)
subject: FOS: Physical sciences

description: The authors report on observation of Bragg confined mode in a hollow cylindrical dielectric cavity. A resonance was observed at 13.4 $GHz$ with an unloaded Q-factor of order $2\times10^5$, which is more than a factor of 6 above the dielectric loss limit. Previously such modes have only been realized from pure Transverse Electric modes with no azimuthal variations and only the $E_ϕ$ component. From rigorous numeric simulations it is shown that the mode is a hybrid mode with non-zero azimuthal variations and with dominant $E_r$ and $E_ϕ$ electric field components and $H_z$ magnetic field component.
description: Accepted to be published in Applied Physics Letters
Beyond the rainbow: effects from pion back-coupling
Creators: name: Fischer, Christian S.
name: Williams, Richard
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We investigate hadronic unquenching effects in light quarks and mesons. To this end we take into account the back-coupling of the pion onto the quark propagator within the non-perturbative continuum framework of Schwinger-Dyson equations (SDE) and Bethe-Salpeter equations (BSE). We improve on a previous approach by explicitly solving both the coupled system of DSEs and BSEs in the complex plane and the normalisation problem for Bethe-Salpeter kernels depending on the total momentum of the meson. As a result of our study we find considerable unquenching effects in the spectrum of light pseudoscalar, vector and axial-vector mesons.
description: 9 pages, 5 figures. Minor typos corrected. Version to appear in PRD
Mean field squared and energy-momentum tensor for the hyperbolic vacuum in dS spacetime
Creators: name: Saharian, A. A.
name: Petrosyan, T. A.
name: Torosyan, V. S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We evaluate the Hadamard function and the vacuum expectation values (VEVs) of the field squared and energy-momentum tensor for a massless conformally coupled scalar field in $(D+1)$-dimensional de Sitter (dS) spacetime foliated by spatial sections of negative constant curvature. It is assumed that the field is prepared in the hyperbolic vacuum state. An integral representation for the difference of the Hadamard functions corresponding to the hyperbolic and Bunch-Davies vacua is provided that is well adapted for the evaluation of the expectation values in the coincidence limit. It is shown that the Bunch-Davies state is interpreted as thermal with respect to the hyperbolic vacuum. An expression for the corresponding density of states is provided. The relations obtained for the difference in the VEVs for the Bunch-Davies and hyperbolic vacua are compared with the corresponding relations for the Fulling-Rindler and Minkowski vacua in flat spacetime. The similarity between those relations is explained by the conformal connection of dS spacetime with hyperbolic foliation and Rindler spacetime. As a limiting case, the VEVs for the conformal vacuum in the Milne universe are discussed.
description: 18 pages, no figures, discussion added
Bipolar spintronics: From spin injection to spin-controlled logic
Creators: name: Zutic, Igor
name: Fabian, Jaroslav
name: Erwin, Steven C.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: An impressive success of spintronic applications has been typically realized in metal-based structures which utilize magnetoresistive effects for substantial improvements in the performance of computer hard drives and magnetic random access memories. Correspondingly, the theoretical understanding of spin-polarized transport is usually limited to a metallic regime in a linear response, which, while providing a good description for data storage and magnetic memory devices, is not sufficient for signal processing and digital logic. In contrast, much less is known about possible applications of semiconductor-based spintronics and spin-polarized transport in related structures which could utilize strong intrinsic nonlinearities in current-voltage characteristics to implement spin-based logic. Here we discuss the challenges for realizing a particular class of structures in semiconductor spintronics: our proposal for bipolar spintronic devices in which carriers of both polarities (electrons and holes) contribute to spin-charge coupling. We formulate the theoretical framework for bipolar spin-polarized transport, and describe several novel effects in two- and three-terminal structures which arise from the interplay between nonequilibrium spin and equilibrium magnetization.
description: 16 pages, 7 figures
The Mass Budgets and Spatial Scales of Exoplanet Systems and Protoplanetary Disks
Creators: name: Mulders, Gijs D.
name: Pascucci, Ilaria
name: Ciesla, Fred J.
name: Fernandes, Rachel B.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Planets are born from disks of gas and dust, and observations of protoplanetary disks are used to constrain the initial conditions of planet formation. However, dust mass measurements of Class II disks with ALMA have called into question whether they contain enough solids to build the exoplanets that have been detected to date. In this paper, we calculate the mass and spatial scale of solid material around Sun-like stars probed by transit and radial velocity exoplanet surveys, and compare those to the observed dust masses and sizes of Class II disks in the same stellar mass regime. We show that the apparent mass discrepancy disappears when accounting for observational selection and detection biases. We find a discrepancy only when the planet formation efficiency is below 100%, or if there is a population of undetected exoplanets that significantly contributes to the mass in solids. We identify a positive correlation between the masses of planetary systems and their respective orbital periods, which is consistent with the trend between the masses and the outer radii of Class II dust disks. This implies that, despite a factor 100 difference in spatial scale, the properties of protoplanetary disks seem to be imprinted on the exoplanet population.
description: Accepted for Publication in ApJ
Pollanisus edwardsi Tarmann 2004
Creators: name: Mollet, Bernard
name: Tarmann, Gerhard M.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Zygaenidae
Pollanisus
Pollanisus edwardsi

description: Pollanisus edwardsi
Published data (Tarmann 2004).
Material examined (Table 4). Paratype: 1 ♁ (Figs 51, 52), New South Wales, Mt Kosciusko, 4500 ft, 23.I.1914 (ANIC).
Discussion and differential diagnosis. This species is known from sea level up to mountains at about 1,370 m (4,500 ft). The wing’s feature and the head ratio data are identical to those of P. species 2, but the latter is much smaller. The habitus of P. edwardsi is similar to that of P. subdolosa subdolosa, which differs in smaller size and in head features, with a narrower frons and bigger compound eyes (Tarmann 2004).
Phenology and bionomics. The head ratios are within the values of those of the diurnal species (table 17) suggesting a diurnal behavior. The larval host-plant is unknown.
description: Published as part of Mollet, Bernard & Tarmann, Gerhard M., 2023, Revision of the genus Pollanisus Walker, 1854 (Lepidoptera: Zygaenidae: Procridinae), pp. 1-72 in Zootaxa 5281 (1) on page 19, DOI: 10.11646/zootaxa.5281.1.1, http://zenodo.org/record/7912043
Experimental investigations of solid state steel energy absorbers for earthquake resistant structures
Creators: name: Chow, Foo-Lin
Publisher: name: University of British Columbia
Year: 2010

description: This thesis suggests the use of curved plates and bars of hot rolled mild steel as energy dissipating devices for the design of earthquake-resistant structures. The proposed devices would be used in parallel with isolating systems in buildings or other structures. They are designed to deflect elastically under minor loads such as wind and to deform plastically when subjected to major earthquake loadings. The devices have a large energy absorbing capacity at a high number of cycles; they are economical and, once installed, can be easily inspected and replaced. An engineering method is presented for predicting the number of cycles to failure of the devices. The practical application and feasibility of a base-isolated steel structure with discrete yield rings is demonstrated in a model test on a shaking table. A design method for the yield rings is proposed.
Optimal Langevin modelling of out-of-equilibrium molecular dynamics simulations
Creators: name: Micheletti, Cristian
name: Bussi, Giovanni
name: Laio, Alessandro
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: We introduce a scheme for deriving an optimally-parametrised Langevin dynamics of few collective variables from data generated in molecular dynamics simulations. The drift and the position-dependent diffusion profiles governing the Langevin dynamics are expressed as explicit averages over the input trajectories. The proposed strategy is applicable to cases when the input trajectories are generated by subjecting the system to a external time-dependent force (as opposed to canonically-equilibrated trajectories). Secondly, it provides an explicit control on the statistical uncertainty of the drift and diffusion profiles. These features lend to the possibility of designing the external force driving the system so to maximize the accuracy of the drift and diffusions profile throughout the phase space of interest. Quantitative criteria are also provided to assess a posteriori the satisfiability of the requisites for applying the method, namely the Markovian character of the stochastic dynamics of the collective variables.
description: To be published on Journal of Chemical Physics
On the Magnitude of Dark Energy Voids and Overdensities
Creators: name: Mota, David F.
name: Shaw, Douglas J.
name: Silk, Joseph
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We investigate the clustering of dark energy within matter overdensities and voids. In particular, we derive an analytical expression for the dark energy density perturbations, which is valid both in the linear, quasi-linear and fully non-linear regime of structure formation. We also investigate the possibility of detecting such dark energy clustering through the ISW effect. In the case of uncoupled quintessence models, if the mass of the field is of order the Hubble scale today or smaller, dark energy fluctuations are always small compared to the matter density contrast. Even when the matter perturbations enter the non-linear regime, the dark energy perturbations remain linear. We find that virialised clusters and voids correspond to local overdensities in dark energy, with $δ_ϕ/(1+w) \sim \Oo(10^{-5})$ for voids, $δ_ϕ/(1+w) \sim \Oo(10^{-4})$ for super-voids and $δ_ϕ/(1+w) \sim \Oo(10^{-5})$ for a typical virialised cluster. If voids with radii of $100-300 {\rm Mpc}$ exist within the visible Universe then $δ_ϕ$ may be as large as $10^{-3}(1+w)$. Linear overdensities of matter and super-clusters generally correspond to local voids in dark energy; for a typical super-cluster: $δ_ϕ/(1+w) \sim \Oo(-10^{-5})$. The approach taken in this work could be straightforwardly extended to study the clustering of more general dark energy models.
description: 20 pages, 14 figures. Accepted by the Astrophys. J
Event Guided Depth Sensing
Creators: name: Muglikar, Manasi
name: Moeys, Diederik Paul
name: Scaramuzza, Davide
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: FOS: Computer and information sciences

description: Active depth sensors like structured light, lidar, and time-of-flight systems sample the depth of the entire scene uniformly at a fixed scan rate. This leads to limited spatio-temporal resolution where redundant static information is over-sampled and precious motion information might be under-sampled. In this paper, we present an efficient bio-inspired event-camera-driven depth estimation algorithm. In our approach, we dynamically illuminate areas of interest densely, depending on the scene activity detected by the event camera, and sparsely illuminate areas in the field of view with no motion. The depth estimation is achieved by an event-based structured light system consisting of a laser point projector coupled with a second event-based sensor tuned to detect the reflection of the laser from the scene. We show the feasibility of our approach in a simulated autonomous driving scenario and real indoor sequences using our prototype. We show that, in natural scenes like autonomous driving and indoor environments, moving edges correspond to less than 10% of the scene on average. Thus our setup requires the sensor to scan only 10% of the scene, which could lead to almost 90% less power consumption by the illumination source. While we present the evaluation and proof-of-concept for an event-based structured-light system, the ideas presented here are applicable for a wide range of depth-sensing modalities like LIDAR, time-of-flight, and standard stereo. Video is available at \url{https://youtu.be/Rvv9IQLYjCQ}.
Phases of Dense Quarks at Large N_c
Creators: name: McLerran, Larry
name: Pisarski, Robert D.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In the limit of a large number of colors, N_c, we suggest that gauge theories can exhibit several distinct phases at nonzero temperature and quark density. Two are familiar: a cold, dilute phase of confined hadrons, where the pressure is ~ 1, and a hot phase of deconfined quarks and gluons, with pressure ~ N_c^2. When the quark chemical potential mu ~ 1, the deconfining transition temperature, T_d, is independent of mu. For T < T_d, as mu increases above the mass threshold, baryons quickly form a dense phase where the pressure is ~ N_c. As illustrated by a Skyrme crystal, chiral symmetry can be both spontaneously broken, and then restored, in the dense phase. While the pressure is ~ N_c, like that of (non-ideal) quarks, the dense phase is still confined, with interactions near the Fermi surface those of baryons, and not of quarks. Thus in the chirally symmetric region, baryons near the Fermi surface are parity doubled. We suggest possible implications for the phase diagram of QCD.
description: 23 pages, 2 figures, uses entcs macro. Minor changes in wording
Sources of uncertainties in the s-process in massive stars: convection and reaction rates
Creators: name: Costa, V.
name: Pumo, M. L.
name: Bonanno, A.
name: Zappala', R. A.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Current models of s-nucleosynthesis in massive stars ($M\sim15 M_{\odot}$ to $\sim 30 M_{\odot}$) are able to reproduce some main features of the abundance distributions of heavy isotopes in the solar system, at least in the $A\sim 60-90$ mass range. The efficiency of the process and the above specified mass range for the s-nuclei are still heavily uncertain due to both nuclear reaction rates and stellar models uncertainties. A series of s-process simulations with stellar models in the $15-30 M_{\odot}$ (mass at ZAMS) and metallicity $Z=0.02$ mass have been performed to analyse the impact of the overshooting model used on the s-process yields. As in a previous exploratory work performed with stellar models having $M_{ZAMS}=25 M_{\odot}$ and $Z=0.02$, enhancements factors in the range 2-5 are found in the final s-process efficiency when overshooting is inserted in the models.
description: 4 pages, 2 figures, Proceedings of the ''Catania workshop on nuclear and neutrino astrophysics''
Quasiharmonic elastic constants corrected for deviatoric thermal stresses
Creators: name: Carrier, Pierre
name: Justo, João F.
name: Wentzcovitch, Renata M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: The quasiharmonic approximation (QHA), in its simplest form also called the statically constrained (SC) QHA, has been shown to be a straightforward method to compute thermoelastic properties of crystals. Recently we showed that for non-cubic solids SC-QHA calculations develop deviatoric thermal stresses at high temperatures. Relaxation of these stresses leads to a series of corrections to the free energy that may be taken to any desired order, up to self-consistency. Here we show how to correct the elastic constants obtained using the SC-QHA. We exemplify the procedure by correcting to first order the elastic constants of MgSiO$_3$-perovskite and MgSiO$_3$-post-perovskite, the major phases of the Earth's lower mantle. We show that this first order correction is quite satisfactory for obtaining the aggregated elastic averages of these minerals and their velocities in the lower mantle. This type of correction is also shown to be applicable to experimental measurements of elastic constants in situations where deviatoric stresses can develop, such as in diamond anvil cells.
description: 4 figures, 1 table, submitted to Phys. Rev. B, July 2008
Ensemble Learning For Mega Man Level Generation
Creators: name: Li, Bowei
name: Chen, Ruohan
name: Xue, Yuqing
name: Wang, Ricky
name: Li, Wenwen
name: Guzdial, Matthew
Publisher: name: arXiv
Year: 2021
Subjects: subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Procedural content generation via machine learning (PCGML) is the process of procedurally generating game content using models trained on existing game content. PCGML methods can struggle to capture the true variance present in underlying data with a single model. In this paper, we investigated the use of ensembles of Markov chains for procedurally generating \emph{Mega Man} levels. We conduct an initial investigation of our approach and evaluate it on measures of playability and stylistic similarity in comparison to a non-ensemble, existing Markov chain approach.
description: 9 pages, 7 figures, Workshop on Procedural Content Generation
Electronic structure of spin 1/2 Heisenberg antiferromagnetic systems: Ba_2Cu(PO_4)_2 and Sr_2Cu(PO_4)_2
Creators: name: Salunke, Sarita S.
name: Ahsan, M. A. H.
name: Nath, R.
name: Mahajan, A. V.
name: Dasgupta, I.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We have employed first principles calculations to study the electronic structure and magnetic properties of the low-dimensional phosphates, Ba2Cu(PO4)2 and Sr2Cu(PO4)2. Using the self-consistent tight-binding lin- earized muffin-tin orbital method and the Nth order muffin-tin orbital method, we have calculated the various intrachain as well as the interchain hopping parameters between the magnetic ions Cu2+ for both the com- pounds. We find that the nearest-neighbor intrachain hopping t is the dominant interaction suggesting the compounds to be indeed one dimensional. Our analysis of the band dispersion, orbital projected band struc- tures, and the hopping parameters confirms that the Cu2+-Cu2+ super-super exchange interaction takes place along the crystallographic b direction mediated by O-P-O. We have also analyzed in detail the origin of short-range exchange interaction for these systems. Our ab initio estimate of the ratio of the exchange inter- action of Sr2Cu(PO4)2 to that of Ba2Cu(PO4)2 compares excellently with available experimental results.
description: 6 pages, 4 figures
$m_c$ (and $m_b$) from lattice QCD
Creators: name: Lytle, Andrew T.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Quark mass determinations based on lattice QCD simulations have continued to make strides in recent years. Here I review that progress with a focus on developments computing the charm (and bottom) quark masses since the 2015 edition of CHARM. These advances have resulted in groups now quoting (sub-)percent-level precision for these quantities, and, importantly, using a variety of techniques subject to differing systematic uncertainties. Improvements to quantify the effects of QED are also now being included. I will highlight three of the strategies being used to determine $m_c$ at this level of precision.
description: Contribution to the Proceedings for 10th International Workshop on Charm Physics (CHARM 2020), May 31-June 5 2021, Mexico City, Mexico. 11 pages, 5 figures. v2: Updated acknowledgements
Discoveries of 3 K-shell Lines of Iron and a Coherent Pulsation of 593-sec from SAX J1748.2-2808
Creators: name: Nobukawa, Masayoshi
name: Koyama, Katsuji
name: Matsumoto, Hironori
name: Tsuru, Takeshi Go
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: SAX J1748.2$-$2808 is a unique X-ray object with a flat spectrum and strong emission lines at 6.4--7.0 keV. The Suzaku satellite resolved the emission lines into 3 K-shell lines from neutral and highly ionized irons. A clear coherent pulsation with a period of 593-sec was found from the Suzaku and XMM-Newton archives. These facts favor that SAX J1748.2$-$2808 isan intermediate polar, a subclass of magnetized white dwarf binary (cataclysmic variable: CV). This paper reports on details of the findings and discusses the origin of this source.
description: 7 pages, 8 figures, Submitted to PASJ on 2008, May 19, Accepted on 2008, June 22
Pollanisus undefined-2
Creators: name: Mollet, Bernard
name: Tarmann, Gerhard M.
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Lepidoptera
Zygaenidae
Pollanisus
Pollanisus undefined-2

description: Pollanisus species 2
Published data (Tarmann 2004).
Material examined (Table 4). 1 ♁ (Figs 53–54), New South Wales, Murramarrang N. P., 1993, e. l. on Kennedia rubicunda, A. Gibbs leg. (ANIC).
Discussion and differential diagnosis. Pollanisus edwardsi and P. species 2 share similar dark fore and hindwings (Tarmann 2004) but P. species 2 is much smaller. P. edwardsi and P. species 2 share the head ratio data, as also with P. trimacula, but the latter has a dark proboscis (yellow in P. edwardsi and P. species 2) and differs in habitus by the presence of ochreous spots (although these are often missing) on the narrow forewing and the translucent central area part in the hindwing. P. trimacula is also known from Murramarang N. P. The habitus of P. species 2 is similar to that of P. subdolosa subdolosa, which differs in a bigger size and in the head features with a narrower frons and bigger compound eyes.
Phenology and bionomics. The larval host-plant of Pollanisus species 2 is Kennedia rubicunda (Fabaceae) (Tarmann 2004), which has a large distribution from sea level to mountain areas and could be also the larval host-plant of P. edwardsi (Fig. 55). Conspecifity between these two species cannot be excluded.
Distribution map (Fig. 55).
description: Published as part of Mollet, Bernard & Tarmann, Gerhard M., 2023, Revision of the genus Pollanisus Walker, 1854 (Lepidoptera: Zygaenidae: Procridinae), pp. 1-72 in Zootaxa 5281 (1) on pages 20-21, DOI: 10.11646/zootaxa.5281.1.1, http://zenodo.org/record/7912043
Porewater pressure response of an artificial island to wave loading
Creators: name: Yogendrakumar, Muthucumarasamy
Publisher: name: University of British Columbia
Year: 2010

description: Plans for the future development of hydrocarbon reserves in the Western Canadian Arctic are based on the use of Caisson retained and Tanker islands as platforms for exploration drilling and future production. At present, the design of these islands are based on current geotechnical engineering design procedures. As exploration progresses towards deeper waters, the need for secure designs is indeed necessary. To be able to achieve this, one requires more sophisticated analytical procedures with the ability to quantify the probable response of these islands to environmental loadings. The chief environmental loads are due to ice, wave and earthquake. A computer based method of analysis is presented for determining the porewater pressure response of these islands to wave loading. The method considers both dissipation and generation effects during wave loading. It also takes into account of the effect of increasing porewater pressure on soil properties. The computer program was used to analyse three different artificial islands subjected to different patterns of storm waves, each of duration 6 hours. The results of the analyses are presented and discussed.