cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Emergence of supersymmetry at a critical point of a lattice model
Creators: name: Lee, Sung-Sik
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: High Energy Physics - Lattice (hep-lat)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Supersymmetry is a symmetry between a boson and a fermion. Although there is no apparent supersymmetry in nature, its mathematical consistency and appealing property have led many people to believe that supersymmetry may exist in nature in the form of a spontaneously broken symmetry. In this paper, we explore an alternative possibility by which supersymmetry is realized in nature, that is, supersymmetry dynamically emerges in the low energy limit of a non-supersymmetric condensed matter system. We propose a 2+1D lattice model which exhibits an emergent space-time supersymmetry at a quantum critical point. It is shown that there is only one relevant perturbation at the supersymmetric critical point in the $ε$-expansion and the critical theory is the two copies of the Wess-Zumino theory with four supercharges. Exact critical exponents are predicted.
description: 7 pages, 5 figures; v5) expanded for publication in Phys. Rev. B
Stochastic equation and exponential ergodicity in Wasserstein distances for affine processes
Creators: name: Friesen, Martin
name: Jin, Peng
name: Rüdiger, Barbara
Publisher: name: arXiv
Year: 2019
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 37A25, 60H10, 60J25

description: This work is devoted to the study of conservative affine processes on the canonical state space $D = $R_+^m \times \R^n$, where $m + n > 0$. We show that each affine process can be obtained as the pathwise unique strong solution to a stochastic equation driven by Brownian motions and Poisson random measures. Then we study the long-time behavior of affine processes, i.e., we show that under first moment condition on the state-dependent and log-moment conditions on the state-independent jump measures, respectively, each subcritical affine process is exponentially ergodic in a suitably chosen Wasserstein distance. Moments of affine processes are studied as well.
Rows of optical vortices from elliptically perturbing a high-order beam
Creators: name: Dennis, M. R.
Publisher: name: arXiv
Year: 2006
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: An optical vortex (phase singularity) with a high topological strength resides on the axis of a high-order light beam. The breakup of this vortex under elliptic perturbation into a straight row of unit strength vortices is described. This behavior is studied in helical Ince-Gauss beams and astigmatic, generalized Hermite-Laguerre-Gauss beams, which are perturbations of Laguerre-Gauss beams. Approximations of these beams are derived for small perturbation, in which a neighborhood of the axis can be approximated by a polynomial in the complex plane: a Chebyshev polynomial for Ince-Gauss beams, and a Hermite polynomial for astigmatic beams.
description: 3 pages, 1 figure. Optics Letters style
Project ThaiPASS: International Outreach Blending Astronomy and Python
Creators: name: Keegans, James D.
name: Stancliffe, Richard J.
name: Bilton, Lawrence E.
name: Cashmore, Claire R.
name: Gibson, Brad K.
name: Kristensen, Mikkel T.
name: Lawson, Thomas V.
name: Pignatari, Marco
name: Vaezzadeh, Iraj
name: Côté, Benoit
name: Chongchitnan, Siri
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: $\textit{Thailand-UK Python+Astronomy Summer School}$ (ThaiPASS), a collaborative project comprising UK and Thai institutions and assess its impact and possible application to schools in the United Kingdom. Since its inception in 2018, the annual ThaiPASS have trained around 60 Thai high-school students in basic data handling skills using Python in the context of various astronomy topics, using current research from the teaching team. Our impact assessment of the 5 day summer schools show an overwhelmingly positive response from students in both years, with over $80\%$ of students scoring the activities above average in all activities but one. We use this data to suggest possible future improvements. We also discuss how ThaiPASS may inspire further outreach and engagement activities within the UK and beyond.
description: Accepted for publication into Physics Education; 21 pages, 5 figures and 3 tables
Security evaluation of transform domain speech scramblers
Creators: name: Theberge, Marc
Publisher: name: University of British Columbia
Year: 2009

description: A number of new speech scrambling algorithms have been recently proposed. Few of them have had their security evaluated. Therefore, this work first concentrates on evaluating, on comparable grounds, various analog speech scramblers. Particular attention is placed on the transform domain speech scramblers. Various attacks are applied to the speech scramblers to evaluate their susceptibility to cryptanalysis. To determine the effectiveness of the cryptanalytic attacks, various measures are proposed and evaluated. These consist of objective distance measures and subjective tests. A novel objective distance measure that emphasizes the lower portion of the log power spectral density of the speech is defined and compared to other objective distance measures. A subjective test that not only tests for lexical residual intelligibility but also for syntactic intelligibility is adapted from audiology experiments used to determine how the working memory affects speech understanding. It is shown that real comprehension of speech may be measured with a lexical intelligibility measure alone, in the specific case where the residual intelligibility of the cryptanalyzed speech is high. However, it is believed that overall speech comprehension is better represented by a composite measure made up of both a lexical and a syntactic intelligibility score. Through the subjective tests, and from the objective measures, it was determined that the transform domain speech scramblers are all seriously vulnerable to simple cryptanalytic attacks. In contrast to [9], the discrete cosine transform (DCT) based scramblers were not found to be more secure than the discrete Fourier transform (DFT) based scramblers. Finally, a noisy modulo addition approach to transform domain speech scrambling is proposed. The scrambling scheme consists of adding pseudo-random noise modulo a certain constant to the quantized spectrum of the speech signal. This method scrambles speech in such a way that it resembles white gaussian noise, and thus traditional cryptanalysis techniques cannot be used to attack it. Its performances under a variety of conditions are discussed.
Testing the Hilbert space dimension
Creators: name: Brunner, Nicolas
name: Pironio, Stefano
name: Acin, Antonio
name: Gisin, Nicolas
name: Methot, Andre Allan
name: Scarani, Valerio
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Given a set of correlations originating from measurements on a quantum state of unknown Hilbert space dimension, what is the minimal dimension d necessary to describes such correlations? We introduce the concept of dimension witness to put lower bounds on d. This work represents a first step in a broader research program aiming to characterize Hilbert space dimension in various contexts related to fundamental questions and Quantum Information applications.
description: 4 pages, 1 figure; Accepted for publication in PRL
Weak-coupling limit for ergodic environments
Creators: name: Friesen, Martin
name: Kondratiev, Yuri
Publisher: name: arXiv
Year: 2019
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 37N25, 46N30, 46N55, 47N30, 92D1

description: The main aim of this work is to establish an averaging principle for a wide class of interacting particle systems in the continuum. This principle is an important step in the analysis of Markov evolutions and is usually applied for the associated semigroups related to backward Kolmogorov equations, c.f. [Kur73]. Our approach is based on the study of forward Kolmogorov equations (a.k.a. Fokker- Planck equations). We describe a system evolving as a Markov process on the space of finite configurations, whereas its rates depend on the actual state of another (equilibrium) process on the space of locally finite configurations. We will show that ergodicity of the environment process implies the averaging principle for the solutions of the coupled Fokker-Planck equations.
Zero-temperature Kosterlitz-Thouless transition in a two-dimensional quantum system
Creators: name: Castelnovo, Claudio
name: Chamon, Claudio
name: Mudry, Christopher
name: Pujol, Pierre
name: .
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: We construct a local interacting quantum dimer model on the square lattice, whose zero-temperature phase diagram is characterized by a line of critical points separating two ordered phases of the valence bond crystal type. On one side, the line of critical points terminates in a quantum transition inherited from a Kosterlitz-Thouless transition in an associated classical model. We also discuss the effect of a longer-range dimer interactions that can be used to suppress the line of critical points by gradually shrinking it to a single point. Finally, we propose a way to generalize the quantum Hamiltonian to a dilute dimer model in presence of monomers and we qualitatively discuss the phase diagram.
description: (30 pages, 11 figures), v2 with minor corrections
Compagnie française du Phenix, Agentur
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Mulhouse
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
Non-Gaussian entanglement criteria for atomic homodyne detection
Creators: name: Lee, Jaehak
name: Park, Jiyong
name: Kim, Jaewan
name: Kim, M. S.
name: Nha, Hyunchul
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Homodyne measurement is a crucial tool widely used to address continuous variables for bosonic quantum systems. While an ideal homodyne detection provides a powerful analysis, e.g. to effectively measure quadrature amplitudes of light in quantum optics, it relies on the use of a strong reference field, the so-called local oscillator typically in a coherent state. Such a strong coherent local oscillator may not be readily available particularly for a massive quantum system like Bose-Einstein condensate (BEC), posing a substantial challenge in dealing with continuous variables appropriately. It is necessary to establish a practical framework that includes the effects of non-ideal local oscillators for a rigorous assessment of various quantum tests and applications. We here develop entanglement criteria beyond Gaussian regime applicable for this realistic homodyne measurement that do not require assumptions on the state of local oscillators. We discuss the working conditions of homodyne detection to effectively detect non-Gaussian quantum entanglement under various states of local oscillators.
description: 9 pages, 5 figures
Calculation of Elastic Constants of $γCe$
Creators: name: Rezaeian, P.
name: Asadabadi, S. Jalali
name: Amini, H.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In this paper we calculated the elastic constants of $γCe$. The calculations were performed self-consistently using the full potential augmented plane wave plus local orbital (FP-APW+lo) method. We used the generalized gradient approximation (GGA) to calculate the exchange-correlation energy. The elastic constants were obtained from the second order derivatives of energy with respect to lattice parameters. In this work we introduced a method to impose a deformation to the primary structure to simplify our calculations changing an fcc structure to bct.
description: 3 Pages, 3 Figures
Design and manufacturing status of advanced structures for reusable launch systems demonstrators with retro propulsion assisted landing technologies (RETALT)
Creators: name: Starke, P.
name: Dorbath, C.
Publisher: name: Zenodo
Year: 2019
Subjects: Structures
Landing legs

description: This presentation given at the EUCASS2019 meeting gives an overview of the MT Aerospace Involvement in the RETALT project
SkyMapper colours of Seyfert galaxies and Changing-Look AGN
Creators: name: Wolf, Christian
name: Golding, Jacob
name: Hon, Wei Jeat
name: Onken, Christopher A.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We study the utility of broad-band colours in the SkyMapper Southern Survey for selecting Seyfert galaxies at low luminosity. We find that the $u-v$ index, built from the ultraviolet $u$ and violet $v$ filters, separates normal galaxies, starburst galaxies and type-1 AGN. This $u-v$ index is not sensitive to age or metallicity in a stellar population but is instead a quenching-and-bursting indicator in galaxies and detects power-law continua in type-1 AGN. Using over 25,000 galaxies at $z<0.1$ from 6dFGS, we find a selection cut based on $u-v$ and central $u$ band brightness that identifies type-1 AGN. By eyeballing 6dFGS spectra we classify new Seyfert galaxies of type 1 to 1.8. Our sample includes eight known Changing-Look AGN, two of which show such strong variability that they move across the selection cut during the five years of SkyMapper observations in DR3, along mixing sequences of nuclear and host galaxy light. We identify 46 Changing-Look AGN candidates in our sample, one of which has been reported as a type-IIn supernova. We show that this transient persists for at least five years and marks a flare in a Seyfert-1 period of a new Changing-Look AGN.
description: Accepted for publication in MNRAS
Courvoisier, Auguste
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Basel
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
Kernel Dependence Network
Creators: name: Wu, Chieh
name: Masoomi, Aria
name: Gretton, Arthur
name: Dy, Jennifer
Publisher: name: arXiv
Year: 2020
Subjects: subject: Machine Learning (cs.LG)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences

description: We propose a greedy strategy to spectrally train a deep network for multi-class classification. Each layer is defined as a composition of linear weights with the feature map of a Gaussian kernel acting as the activation function. At each layer, the linear weights are learned by maximizing the dependence between the layer output and the labels using the Hilbert Schmidt Independence Criterion (HSIC). By constraining the solution space on the Stiefel Manifold, we demonstrate how our network construct (Kernel Dependence Network or KNet) can be solved spectrally while leveraging the eigenvalues to automatically find the width and the depth of the network. We theoretically guarantee the existence of a solution for the global optimum while providing insight into our network's ability to generalize.
description: arXiv admin note: substantial text overlap with arXiv:2006.08539
Carmi, Amadeo
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Reggio
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
Modeling of Thermal Magnetic Fluctuations in Nanoparticle Enhanced Magnetic Resonance Detection
Creators: name: Kaisar, Tahmid
name: Rajib, Md Mahadi
name: ElBidweihy, Hatem
name: Barbic, Mladen
name: Atulasimha, Jayasimha
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: We present a systematic numerical modeling investigation of magnetization dynamics and thermal magnetic moment fluctuations of single magnetic domain nanoparticles in a configuration applicable to enhancing inductive magnetic resonance detection signal to noise ratio (SNR). Previous proposals for oriented anisotropic single magnetic domain nanoparticle amplification of magnetic flux in MRI coil focused only on the coil pick-up voltage signal enhancement. Here we extend the analysis to the numerical evaluation of the SNR by modeling the inherent thermal magnetic noise introduced into the detection coil by the insertion of such anisotropic nanoparticle-filled coil core. We utilize the Landau-Lifshitz-Gilbert equation under the Stoner-Wohlfarth single magnetic domain (macrospin) assumption to simulate the magnetization dynamics in such nanoparticles due to AC drive field as well as thermal noise. These simulations are used to evaluate the nanoparticle configurations and shape effects on enhancing SNR. Finally, we explore the effect of narrow band filtering of the broadband magnetic moment thermal fluctuation noise on the SNR. Our results provide the impetus for relatively simple modifications to existing MRI systems for achieving enhanced detection SNR in scanners with modest polarizing magnetic fields.
Ferroelectric Transition Induced by the Incommensurate Magnetic Ordering in LiCuVO4
Creators: name: Naito, Yutaka
name: Sato, Kenji
name: Yasui, Yukio
name: Kobayashi, Yusuke
name: Kobayashi, Yoshiaki
name: Sato, Masatoshi
Publisher: name: arXiv
Year: 2006
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: A ferroelectric transition occurring simultaneously with helical spin order has been found in both the polycrystalline and single crystal samples of LiCuVO4. The system has Cu2+ spins (s=1/2) of the CuO2 chains formed of edge-sharing CuO4 squares. Possibly due to the frustrated nature caused by the competition between the nearest-neighbor and next-nearest-neighbor exchange interactions, Cu spins exhibit, as has been already reported, the helical magnetic order with the incommensurate modulation vector Q along the chain direction and with the helical axis e3 perpendicular to the CuO4 squares. The electric polarization P can be understood by the recently predicted relation (P is proportional to Q*e3). The transition temperature has been found to be gradually suppressed by the applied magnetic field.
description: 6 pages, 4 figures, submitted to JPSJ
Chary, Joseph
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Mainz
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
A generalized post-detector compatible soft-output vitebri algorithm (sova)
Creators: name: Kwan, David
Publisher: name: University of British Columbia
Year: 2009

description: A generalized soft-output Viterbi algorithm (SOVA) that is applicable to any (n, k, m) convolutional code is proposed. The algorithm is compatible with the post-detector architecture proposed by Berrou et al. thereby achieving low computational complexity. By starting with Battail's generalized revision algorithm and re-referencing the relative values to the surviving path to each state, significant simplifications are made possible. By comparing the resultant simplified revision equation for (n,1,m) convolutional codes with Berrou's proposed post-detector compatible algorithm it is possible to deduce the additional modifications necessary to arrive at a (n,k,m) post detector compatible algorithm. Simulations show that with a revision depth greater than five times a code's constraint length, the proposed algorithm is capable of producing relatively high quality a posteriori input symbol estimates.
Gravitational Waves in f(R) Gravity Power Law Model
Creators: name: Gogoi, Dhruba Jyoti
name: Goswami, Umananda Dev
Publisher: name: arXiv
Year: 2019
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We investigate the different polarization modes of Gravitational Waves (GWs) in $f(R)$ gravity power law model in de Sitter space. It is seen that the massive scalar field polarization mode exists in this model. The mass of the scalar field depends highly on the background curvature and the power term $n$. However, we found that the model doesnot exhibit a massive scalar mode for $n=2$ and instead it shows a breathing mode in addition to the tensor plus and cross modes. Thus mass of the scalar field is found to vary with $n$ within the range $1 \leq n \leq 2$.
description: 12 pages, 3 figures
Dynamics of mode-locked nanolasers based on Hermite-Gaussian modes
Creators: name: Sun, Yifan
name: Combrié, Sylvain
name: De Rossi, Alfredo
name: Bretenaker, Fabien
Publisher: name: arXiv
Year: 2020
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: The different dynamical behaviors of the Hermite-Gaussian (HG) modes of mode-locked nanolasers based on a harmonic photonic cavity are investigated in detail using a model based on a modified Gross-Pitaevskii Equation. Such nanolasers are shown to exhibit mode-locking with a repetition rate independent of the cavity length, which is a strong asset for compactness.The differences with respect to conventional lasers are shown to originate from the peculiar gain competition between HG modes, which is investigated in details. In the presence of a saturable absorber, the different regimes, i. e. Q-switching, Q-switched mode-locking, and continuous-wave (cw) mode locking, are isolated in a phase diagram and separately described. Mode-locking is found to be robust against phase-intensity coupling and to be achievable in a scheme with spatially separated gain and absorber.
description: to be published in Physical Review A
A Fast Linear Regression via SVD and Marginalization
Creators: name: Greengard, Philip
name: Gelman, Andrew
name: Vehtari, Aki
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computation (stat.CO)
subject: Numerical Analysis (math.NA)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: We describe a numerical scheme for evaluating the posterior moments of Bayesian linear regression models with partial pooling of the coefficients. The principal analytical tool of the evaluation is a change of basis from coefficient space to the space of singular vectors of the matrix of predictors. After this change of basis and an analytical integration, we reduce the problem of finding moments of a density over k + m dimensions, to finding moments of an m-dimensional density, where k is the number of coefficients and k + m is the dimension of the posterior. Moments can then be computed using, for example, MCMC, the trapezoid rule, or adaptive Gaussian quadrature. An evaluation of the SVD of the matrix of predictors is the dominant computational cost and is performed once during the precomputation stage. We demonstrate numerical results of the algorithm. The scheme described in this paper generalizes naturally to multilevel and multi-group hierarchical regression models where normal-normal parameters appear.
title: Del Rio Residence Rock Slope Protection project
titleType: AlternativeTitle
title: Endangered Species Act Section 7(a)(2) Biological Opinion and Magnuson-Stevens Fishery Conservation and Management Act Essential Fish Habitat Response for the Del Rio Residence Rock Slope Protection Project
Creators: name: United States. National Marine Fisheries Service. West Coast Region
Publisher: name: United States. National Marine Fisheries Service. West Coast Region
Year: 2023

description: WCRO-2023-01945
Compagnie d'Assurance Suisse
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Livorno
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
Optically-thick Structure in Early B Type Supergiant Stellar Winds at Low Metallicities
Creators: name: Parsons, Timothy N.
name: Prinja, Raman K.
name: Bernini-Peron, Matheus
name: Fullerton, Alex W.
name: Massa, Derck L.
name: Oskinova, Lidia M.
name: Pauli, Daniel
name: Sander, Andreas A. C.
name: Rickard, Matthew J.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Accurate determination of mass-loss rates from massive stars is important to understanding stellar and galactic evolution and enrichment of the interstellar medium. Large-scale structure and variability in stellar winds have significant effects on mass-loss rates. Time-series observations provide direct quantification of such variability. Observations of this nature are available for some Galactic early supergiant stars but not yet for stars in lower metallicity environments such as the Magellanic Clouds. We utilise ultraviolet spectra from the Hubble Space Telescope ULLYSES program to demonstrate that the presence of structure in stellar winds of supergiant stars at low metallicities may be discerned from single-epoch spectra. We find evidence that, for given stellar luminosities and mean stellar wind optical depths, structure is more prevalent at higher metallicities. We confirm, at Large Magellanic Cloud (0.5 Z_solar), Small Magellanic Cloud (0.2 Z_solar) and lower (0.14 -- 0.1 Z_solar) metallicities, earlier Galactic results that there does not appear to be correlation between the degree of structure in stellar winds of massive stars and stellar effective temperature. Similar lack of correlation is found with regard to terminal velocity of stellar winds. Additional and revised values for radial velocities of stars and terminal velocities of stellar winds are presented. Direct evidence of temporal variability, on timescales of several days, in stellar wind at low metallicity is found. We illustrate that narrow absorption components in wind-formed profiles of Galactic OB stellar spectra remain common in early B supergiant spectra at low metallicities, providing means for better constraining hot, massive star mass-loss rates.
description: 18 pages plus Appendices, 9 figures plus 37 figures in Appendices. Accepted by MNRAS
Experience gravity in the classroom using the rubber sheet: an educational proposal from the collaboration between University and School
Creators: name: Postiglione, Adriana
name: De Angelis, Ilaria
Publisher: name: arXiv
Year: 2021
Subjects: subject: Physics Education (physics.ed-ph)
subject: FOS: Physical sciences

description: Teaching modern physics in high school is of increasingly importance as it can offer students a more realistic and updated vision of the world, and can provide an opportunity to understand the most recent scientific discoveries. In this context, General Relativity (GR) occupies a prominent place, since it is related to astonishing scientific results, such as the first image of a black hole or the discovery of gravitational waves. In this paper we describe an educational proposal aimed at teaching GR in high school in a fun and playful way using the so-called rubber sheet analogy. We present a set of instructions to build a simple and low-cost space-time simulator, and a series of related educational cards that guide the teacher in the implementation of the activities step by step. This work is the result of a long and productive debate among Italian high school teachers who collaborate since many years with the Department of Mathematics and Physics of Roma Tre University in Rome. As our proposal relies on the collaboration with the final users, we believe that it will meet their needs and expectations, and it will help to treat GR in high school more and more over time.
description: Physics Education (2021), in press. This is the version of the article before peer review or editing, as submitted by an author to Physics Education. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it
Chameleon Vector Bosons
Creators: name: Nelson, A. E.
name: Walsh, J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Astrophysics (astro-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We show that for a force mediated by a vector particle coupled to a conserved U(1) charge, the apparent range and strength can depend on the size and density of the source, and the proximity to other sources. This "chameleon" effect is due to screening from a light charged scalar. Such screening can weaken astrophysical constraints on new gauge bosons. As an example we consider the constraints on chameleonic gauged B-L. We show that although Casimir measurements greatly constrain any B-L force much stronger than gravity with range longer than 0.1 microns, there remains an experimental window for a long range chameleonic B-L force. Such a force could be much stronger than gravity, and long or infinite range in vacuum, but have an effective range near the surface of the earth which is less than a micron.
description: 10 pages
Spectroscopic fourth-order coronagraph for the characterization of terrestrial planets at small angular separations from host stars
Creators: name: Matsuo, Taro
name: Itoh, Satoshi
name: Ikeda, Yuji
Publisher: name: arXiv
Year: 2020
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: We propose a new approach for high-contrast imaging at the diffraction limit using segmented telescopes in a modest observation bandwidth. This concept, named "spectroscopic fourth-order coronagraphy", is based on a fourth-order coronagraph with a focal-plane mask that modulates the complex amplitude of the Airy disk along one direction. While coronagraphs applying the complex amplitude mask can achieve the theoretical limit performance for any arbitrary pupils, the focal plane mask severely limits the bandwidth. Here, focusing on the fact that the focal-plane mask modulates the complex amplitude along one direction, we noticed that the mask can be optimized for each spectral element generated by a spectrograph. We combine the fourth-order coronagraph with two spectrographs to produce a stellar spectrum on the focal plane and reconstruct a white pupil on the Lyot stop. Based on the wavefront analysis of an optical design applying an Offner-type imaging spectrograph, we found that the achievable contrast of this concept is 10^{-10} at 1.2 - 1.5 times the diffraction limit over the wavelength range of 650 - 750 nm for the entrance pupil of the LUVOIR telescope. Thus, this coronagraph concept could bring new habitable planet candidates not only around G- and K-type stars beyond 20 - 30 pc but also around very nearby M-type stars. This approach potentially promotes the characterization of the atmospheres of nearby terrestrial planets with future on- and off-axis segmented large telescopes.
description: 26 Pages, 12 Figures, Accepted for publication in The Astronomical Journal
Burger, Friedrich
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Burgdorf
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
title: New Pier (NWS-2021-765, Boat Street Marina)
titleType: AlternativeTitle
title: Endangered Species Act Section 7(a)(2) Biological Opinion and Magnuson-Stevens Fishery Conservation and Management Act Essential Fish Habitat Response for the Boat Street Marina Pier Repair Project in Lake Union, King County, Washington (USACE No. NWS-2021-765; HUC: 171100120400 – Lake Washington)
Creators: name: United States. National Marine Fisheries Service. West Coast Region
Publisher: name: United States. National Marine Fisheries Service. West Coast Region
Year: 2023

description: WCRO-2021-02369
A soft decision concatenated coding scheme for mobile packet radio applications
Creators: name: Poon, Patrick C.H.
Publisher: name: University of British Columbia
Year: 2009

description: Concatenated coding systems can offer good error performance over severely degraded channels. The combination of an inner trellis code and an outer Reed Solomon code has been a popular choice since it offers a good compromise between performance and complexity. In this thesis, a concatenated coded modulation scheme based on trellis coded modulation and a Reed Solomon code in the presence of Rayleigh fading is studied. The inner decoding process uses a soft output Viterbi algorithm which produces reliability information along with its output. This information is used to erase unreliable symbols in the decoded output. An errors-erasures Reed Solomon decoder is then used for the outer code. The block error probability performance gain achievable through the use of a soft output Viterbi algorithm in concatenated coding is studied using analysis and simulation. The effect of finite interleaving for the outer code is also considered.
Chappuis, C. F
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Genf
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
Constructing the CKM and PMNS matrices from mixing data
Creators: name: Ahuja, Gulsheen
name: Gupta, Manmohan
name: Randhawa, Monika
Publisher: name: arXiv
Year: 2006
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The CKM and PMNS matrices have been constructed based on the latest measurements, largely free from theoretical inputs as well as likely NP effects in the case of the former. To facilitate the construction of the CKM matrix in the PDG representation as well as in view of the comparatively large error in the measured value of the CP violating phase δ, the possibility of its construction from the tree level measured CKM elements has also been explored using the unitarity triangle. In view of the persistent difference between the |V_{ub}| exclusive and inclusive values, we have carried out separate analyses corresponding to these. The PMNS matrix has been constructed by incorporating the constraints due to solar and atmospheric neutrinos as well as by giving full variation to the Dirac-like CP violating phase δand considering different values of s_{13} having implications for different models of lepton mass matrices. Taking clue from quark mixing phenomenology, an analogous analysis of the leptonic unitarity triangle allows an estimate of the likely presence of CP violation in the leptonic sector.
description: 11 pages, 2 figures
Phenology-pigment based automated peanut mapping using sentinel-2 images
Creators: name: Qiu, Bingwen
name: Jiang, Fanchen
name: Chen, Chongcheng
name: Tang, Zhenghong
name: Wu, Wenbin
name: Berry, Joe
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Medicine
subject: Biotechnology
subject: 59999 Environmental Sciences not elsewhere classified
subject: FOS: Earth and related environmental sciences
subject: 39999 Chemical Sciences not elsewhere classified
subject: FOS: Chemical sciences
subject: Ecology
subject: FOS: Biological sciences
subject: 69999 Biological Sciences not elsewhere classified
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Plant Biology

description: Reliable spatiotemporal crop data are vital for sustainable agricultural management. However, efficient algorithms that can be automatically applied to large regions are scarce, especially for cash crops, since it is hard to distinguish their uniqueness merely from temporal profiles of traditional vegetation indices. The efficiency of knowledge-based temporal features and red-edge pigment indices in characterizing crop growth has been reported in the literature, but the potential of combined applications in identifying crops has not been validated yet. This study fills this gap by developing a knowledge-based automated Peanut mapping Algorithm with a combined consideration of crop Phenology and Pigment content variations (PAPP). Peanut crop has earlier and longer flowering stages compared to other crops such as paddy rice and maize. Peanut fields are distinguished with less variations in anthocyanin and chlorophyll as well as higher carotenoid concentrations. Herein, three phenology and pigment-based indicators were proposed for peanut mapping by exploring the concentration and variations of the chlorophyll, anthocyanin and carotenoid indices, respectively. This PAPP algorithm was validated over large regions (around 250 thousand km2 cropland) covering three provinces of Northeast China using Sentinel-2 time-series images. The results reported that there was 8,371 km2 peanut area in Northeast China in 2018, concentrated in the western Jilin and Liaoning provinces. Validation from the 1,102 field survey sites revealed overall accuracies of 94%, with a kappa index of 0.87 and F1 score of 0.91. The PAPP algorithm was not sensitive to thresholding, and a high classification accuracy could be obtained once the threshold of one indicator was roughly defined. The thresholds could be determined based on the proportions of staple crops (i.e. paddy rice and maize) using the historical agricultural statistical data since peanut fields either show the least or largest values in these three proposed indicators. The PAPP algorithm demonstrates the capabilities of automatic peanut mapping over large regions with no requirements of further training and modifications. This study makes contributions to a sustainable agricultural management society given the potential significant role of legume crops in co-delivering food security and adapting to climate change.
A DFT study of the structural and electronic properties of single and double acceptor dopants in MX2 monolayers
Creators: name: Gao, Yuqiang
name: Kelly, Paul J.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Density functional theory calculations are used to systematically investigate the structural and electronic properties of MX$_2$ transition metal dichalcogenide monolayers with M = Cr, Mo, W and X = S, Se, Te that are doped with single (V, Nb, Ta) and double (Ti, Zr, Hf) acceptor dopants on the M site with local $D_{3h}$ symmetry in the dilute limit. Three impurity levels that arise from intervalley scattering are found above the valence band maxima (VBM): an orbitally doubly degenerate $e'$ level bound to the $K/K'$ VBM and a singly degenerate $a'_1$ level bound to the $Γ$-point VBM. Replacing S with Se or Te lowers the $Γ$ point VBM substantially with respect to the $K/K'$ VBM bringing the $a'_1$ level down with it. The relative positions of the impurity levels that determine the different structural and electronic properties of the impurities in $p$-doped MX$_2$ monolayers can thus be tuned by replacing S with Se or Te.
 Single acceptors introduce a magnetic moment of 1$\, μ_{\rm B}$ in all MX$_2$ monolayers. Out-of-plane magnetic anisotropy energies as large as 10 meV/dopant atom are found thereby satisfying an essential condition for long-range ferromagnetic ordering in two dimensions. For double acceptors in MS$_2$ monolayers, both holes occupy the high-lying $a'_1$ level with opposite spins so there is no magnetic moment; in MSe$_2$ and MTe$_2$ monolayers the holes occupy the $e'$ level, a Jahn-Teller (JT) distortion wins the competition with exchange splitting resulting in the quenching of the magnetic moments. Even when the JT distortion is disallowed, magnetic double acceptors have a large in-plane magnetic anisotropy energy that is incompatible with long-range magnetic ordering in two dimensions. ....
description: 27 pages, 15 figures
Impact of Three-Body Forces on Elastic Nucleon-Nucleus Scattering Observables
Creators: name: Vorabbi, Matteo
name: Gennari, Michael
name: Finelli, Paolo
name: Giusti, Carlotta
name: Navrátil, Peter
name: Machleidt, Ruprecht
Publisher: name: arXiv
Year: 2020
Subjects: subject: Nuclear Theory (nucl-th)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: In a previous series of papers we investigated the domain of applicability of chiral potentials to the construction of a microscopic optical potential (OP) for elastic nucleon-nucleus scattering. The final expression of the OP was a folding integral between the nucleon-nucleon ($NN$) $t$ matrix and the nuclear density of the target. In these calculations $NN$ and three-nucleon ($3N$) chiral interactions were used for the target density and only the $NN$ interaction for the $NN$ $t$ matrix. The purpose of this work is to achieve another step towards the calculation of a more consistent OP introducing the $3N$ force also in the dynamic part of the OP. In the present work this is approximated with a density dependent $NN$ interaction obtained after the averaging over the Fermi sphere. In practice, in our model the $3N$ force acts as a medium correction of the bare $NN$ interaction used to calculate the $NN$ $t$ matrix. Even if the $3N$ force is treated in an approximate way, this method naturally extends our previous model of the OP and allows a direct comparison of our present and previous results. We consider as case studies the elastic scattering of nucleons off $^{12}$C and $^{16}$O. We present results for the differential cross section and the spin observables for different values of the projectile energy. From the comparison with the experimental data and with the results of our previous model we assess the importance of the $3N$ interaction in the dynamic part of the OP. Our analysis indicates that the contribution of the $3N$ force in the $t$ matrix is small for the differential cross section and it is sizable for the spin observables, in particular, for the analyzing power. A chiral expansion order-by-order analysis of the scattering observables confirms the convergence of our results at the next-to-next-to-next-to-leading-order, as already established in our previous work.
title: EPA Approval of Water Quality Standard for Virginia
titleType: AlternativeTitle
title: National Marine Fisheries Service Endangered Species Act Section 7 Biological Opinion Environmental Protection Agency Approval of Virginia’s Adoption of Criteria for Aluminum in Freshwater
Creators: name: United States. National Marine Fisheries Service. Office of Protected Resources
Publisher: name: United States. National Marine Fisheries Service. Office of Protected Resources
Year: 2023

description: OPR-2023-00181
Corti, Frères
Creators: name: [s.n.]
Publisher: name: [s.n.]
Year: 1830

description: Ort: Mailand
description: Verzeichnung=Description=Inventaire 05.07.2020 Automatisiert nach HAN-Import
description: Verzeichnung=Description=Inventaire ISAD(G) / HAN Katalogisierungsregeln für Archivbestände Detailliert
Steady Models of Optically Thin, Magnetically Supported Black Hole Accretion Disks
Creators: name: Oda, H.
name: Machida, M.
name: Nakamura, K. E.
name: Matsumoto, R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We obtained steady solutions of optically thin, single temperature, magnetized black hole accretion disks assuming thermal bremsstrahlung cooling. Based on the results of 3D MHD simulations of accretion disks, we assumed that the magnetic fields inside the disk are turbulent and dominated by azimuthal component. We decomposed magnetic fields into an azimuthally averaged mean field and fluctuating fields. We also assumed that the azimuthally averaged Maxwell stress is proportional to the total pressure. The radial advection rate of the azimuthal magnetic flux $\dot Φ$ is prescribed as being proportional to $\varpi^{- ζ}$, where $\varpi$ is the radial coordinate and $ζ$ is a parameter which parameterizes the radial variation of $\dot Φ$. We found that when accretion rate $\dot M$ exceeds the threshold for the onset of the thermal instability, a magnetic pressure dominated new branch appears. Thus the thermal equilibrium curve of optically thin disk has a 'Z'-shape in the plane of surface density and temperature. This indicates that as the mass accretion rate increases, a gas pressure dominated optically thin hot accretion disk undergoes a transition to a magnetic pressure dominated, optically thin cool disk. This disk corresponds to the X-ray hard, luminous disk in black hole candidates observed during the transition from a low/hard state to a high/soft state. We also obtained global steady transonic solutions containing such a transition layer.
description: 11 pages, 6 figures, accepted by PASJ
Superconductivity at 253 K in lanthanum-yttrium ternary hydrides
Creators: name: Semenok, Dmitrii V.
name: Troyan, Ivan A.
name: Kvashnin, Alexander G.
name: Ivanova, Anna G.
name: Hanfland, Michael
name: Sadakov, Andrey V.
name: Sobolevskiy, Oleg A.
name: Pervakov, Kirill S.
name: Gavriliuk, Alexander G.
name: Lyubutin, Igor S.
name: Glazyrin, Konstantin V.
name: Giordano, Nico
name: Karimov, Denis N.
name: Vasiliev, Alexander B.
name: Akashi, Ryosuke
name: Pudalov, Vladimir M.
name: Oganov, Artem R.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Polyhydrides offer intriguing perspectives as high-temperature superconductors. Here we report the high-pressure synthesis of a series of lanthanum-yttrium ternary hydrides: cubic hexahydride $(La,Y)H_{6}$ with a critical temperature $T_{C}$ = 237 +/- 5 K and decahydrides $(La,Y)H_{10}$ with a maximum $T_{C}$ ~${253 K}$ and an extrapolated upper critical magnetic field $B_{C2(0)}$ up to ${135 T}$ at 183 GPa. This is one of the first examples of ternary high-$T_{C}$ superconducting hydrides. Our experiments show that a part of the atoms in the structures of recently discovered ${Im3m}$-$YH_{6}$ and ${Fm3m}$-$LaH_{10}$ can be replaced with lanthanum (~70 %) and yttrium (~25 %), respectively, with a formation of unique ternary superhydrides containing incorporated $La@H_{24}$ and $Y@H_{32}$ which are specific for ${Im3m}$-$LaH_{6}$ and ${Fm3m}$-$YH_{10}$. Ternary La-Y hydrides were obtained at pressures of 170-196 GPa via the laser heating of $P6_{3}$${/mmc}$ lanthanum-yttrium alloys in the ammonia borane medium at temperatures above 2000 K. A novel tetragonal $(La,Y)H_{4}$ was discovered as an impurity phase in synthesized cubic $(La,Y)H_{6}$. The current-voltage measurements show that the critical current density $J_{C}$ in $(La,Y)H_{10}$ may exceed $2500 A/mm^{2}$ at 4.2 K, which is comparable with that for commercial superconducting wires such as ${NbTi}$, $Nb_{3}$${Sn}$. Hydrides that are unstable in a pure form may nevertheless be stabilized at relatively low pressures in solid solutions with superhydrides having the same structure.