cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Analysis of Lithiation and Delithiation Kinetics in Silicon
Creators: name: Sethuraman, Vijay A.
name: Srinivasan, Venkat
name: Newman, John
Publisher: name: arXiv
Year: 2012
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Analysis of lithiation and delithiation kinetics in pulse-laser-deposited crystalline thin-film silicon (Si) electrodes is presented. Data from open-circuit relaxation experiments are used in conjunction with a model based on Tafel kinetics and double-layer capacitance to estimate the apparent transfer coefficients (αa, αc), and exchange current density to capacitance ratio (i0/Cdl) for lithiation and delithiation reactions in a lithiated silicon (LixSi) system. Parameters estimated from data sets obtained during first-cycle amorphization of crystalline Si, as well as from cycled crystalline Si and amorphous Si thin-film electrodes do not show much variation, indicating that they are intrinsic to lithiation/delithiation in Si. A methodology to estimate the side-reaction rate and its role in the evolution of the open-circuit potential of the LixSi system are discussed. We conclude that the large potential offset between lithiation and delithiation reactions at any given state of charge is partially caused by a large kinetic resistance (i.e., small i0). Using the estimated parameters, the model is shown to predict successfully the behavior of the system under galvanostatic lithiation and delithiation.
description: 35 pages, 14 figures
Turbulence via intermolecular potential: A weakly compressible model of gas flow at low Mach number
Creators: name: Abramov, Rafail V.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: FOS: Physical sciences

description: In our recent works we proposed a theory of turbulence in inertial gas flow via the mean field effect of an intermolecular potential. We found that, in inertial flow, turbulence indeed spontaneously develops from a laminar initial condition, just as observed in nature and experiments. However, we also found that density and temperature in our inertial flow model behave unrealistically. The goal of the current work is to demonstrate technical possibility of modeling compressible, turbulent flow at low Mach number where both density and temperature behave in a more realistic fashion. Here we focus on a new treatment of the pressure variable, which constitutes a compromise between compressible, incompressible and inertial flow. Similarly to incompressible flow, the proposed equation for the pressure variable is artificial, rather than derived directly from kinetic formulation. However, unlike that for incompressible flow, our pressure equation only damps the divergence of velocity, instead of setting it directly to zero. We find that turbulence develops in our weakly compressible model much like it does in the inertial flow model, but density and temperature behave more realistically.
description: 20 pages, 8 figures
Real-world treatment of gout and asymptomatic hyperuricemia
Creators: name: Lai, Shih-Wei
name: Kuo, Yu-Hung
name: Liao, Kuan-Fu
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: 29999 Physical Sciences not elsewhere classified
subject: FOS: Physical sciences
subject: Neuroscience
subject: Physiology
subject: FOS: Biological sciences
subject: Pharmacology
subject: Biotechnology
subject: Ecology
subject: Immunology
subject: FOS: Clinical medicine
subject: 80699 Information Systems not elsewhere classified
subject: FOS: Computer and information sciences
subject: Developmental Biology
subject: Marine Biology
subject: Plant Biology

description: Real-world treatment of gout and asymptomatic hyperuricemia
Solar Magnetic Carpet I: Simulation of Synthetic Magnetograms
Creators: name: Meyer, Karen A.
name: Mackay, Duncan H.
name: van Ballegooijen, Adriaan A.
name: Parnell, Clare E.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: This paper describes a new 2D model for the photospheric evolution of the magnetic carpet. It is the first in a series of papers working towards constructing a realistic 3D non-potential model for the interaction of small-scale solar magnetic fields. In the model, the basic evolution of the magnetic elements is governed by a supergranular flow profile. In addition, magnetic elements may evolve through the processes of emergence, cancellation, coalescence and fragmentation. Model parameters for the emergence of bipoles are based upon the results of observational studies. Using this model, several simulations are considered, where the range of flux with which bipoles may emerge is varied. In all cases the model quickly reaches a steady state where the rates of emergence and cancellation balance. Analysis of the resulting magnetic field shows that we reproduce observed quantities such as the flux distribution, mean field, cancellation rates, photospheric recycle time and a magnetic network. As expected, the simulation matches observations more closely when a larger, and consequently more realistic, range of emerging flux values is allowed (4e16 - 1e19 Mx). The model best reproduces the current observed properties of the magnetic carpet when we take the minimum absolute flux for emerging bipoles to be 4e16 Mx. In future, this 2D model will be used as an evolving photospheric boundary condition for 3D non-potential modeling.
description: 33 pages, 16 figures, 5 gif movies included: movies may be viewed at http://www-solar.mcs.st-and.ac.uk/~karen/movies_paper1/
Experimental validation of machine-learning based spectral-spatial power evolution shaping using Raman amplifiers
Creators: name: Soltani, Mehran
name: Da Ros, Francesco
name: Carena, Andrea
name: Zibar, Darko
Publisher: name: arXiv
Year: 2022
Subjects: subject: Emerging Technologies (cs.ET)
subject: Machine Learning (cs.LG)
subject: Optics (physics.optics)
subject: FOS: Computer and information sciences
subject: FOS: Physical sciences

description: We experimentally validate a real-time machine learning framework, capable of controlling the pump power values of Raman amplifiers to shape the signal power evolution in two-dimensions (2D): frequency and fiber distance. In our setup, power values of four first-order counter-propagating pumps are optimized to achieve the desired 2D power profile. The pump power optimization framework includes a convolutional neural network (CNN) followed by differential evolution (DE) technique, applied online to the amplifier setup to automatically achieve the target 2D power profiles. The results on achievable 2D profiles show that the framework is able to guarantee very low maximum absolute error (MAE) (<0.5 dB) between the obtained and the target 2D profiles. Moreover, the framework is tested in a multi-objective design scenario where the goal is to achieve the 2D profiles with flat gain levels at the end of the span, jointly with minimum spectral excursion over the entire fiber length. In this case, the experimental results assert that for 2D profiles with the target flat gain levels, the DE obtains less than 1 dB maximum gain deviation, when the setup is not physically limited in the pump power values. The simulation results also prove that with enough pump power available, better gain deviation (less than 0.6 dB) for higher target gain levels is achievable.
Measurement of the Charge Asymmetry in Top Quark Pair Production
Creators: name: Böser, Christian
Publisher: name: arXiv
Year: 2012
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: We present a measurement of the charge asymmetry in top quark pair production using an integrated luminosity of 1.09 fb-1 collected with the CMS detector. Top quark pairs with a signature of one electron or muon and four or more jets, at least one of them b tagged, are selected. At the LHC a small charge asymmetry in the rapidity distributions of top and antitop quarks is predicted. Therein slightly broader rapidity distributions for top quarks are expected, while antitop quarks are produced more centrally and possess narrower rapidity distributions. We determine the charge asymmetry based on two different sensitive variables and the results are compared with the most precise standard model theory predictions using a dedicated unfolding technique.
description: Presented at the 2011 Hadron Collider Physics symposium (HCP-2011), Paris, France, November 14-18 2011, 3 pages, 3 figures
Spectral density asymptotics for Gaussian and Laguerre $β$-ensembles in the exponentially small region
Creators: name: Forrester, Peter J.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: The first two terms in the large $N$ asymptotic expansion of the $β$ moment of the characteristic polynomial for the Gaussian and Laguerre $β$-ensembles are calculated. This is used to compute the asymptotic expansion of the spectral density in these ensembles, in the exponentially small region outside the leading support, up to terms $o(1)$ . The leading form of the right tail of the distribution of the largest eigenvalue is given by the density in this regime. It is demonstrated that there is a scaling from this, to the right tail asymptotics for the distribution of the largest eigenvalue at the soft edge.
description: 19 pages
Compactness of localization operators on modulation spaces of $ω$-tempered distributions
Creators: name: Boiti, Chiara
name: De Martino, Antonino
Publisher: name: arXiv
Year: 2019
Subjects: subject: Functional Analysis (math.FA)
subject: FOS: Mathematics

description: We give sufficient conditions for compactness of localization operators on modulation spaces $\textbf{M}^{p,q}_{m_λ}( \mathbb{R}^{d})$ of $ω$-tempered distributions whose short-time Fourier transform is in the weighted mixed space $L^{p,q}_{m_λ}$ for $m_λ(x)=e^{λω(x)}$.
Combined large-$N_c$ and heavy-quark operator analysis of 2-body meson-baryon counterterms in the chiral Lagrangian with charmed mesons
Creators: name: Lutz, M. F. M.
name: Samart, D.
name: Semke, A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The chiral SU(3) Lagrangian with pseudoscalar and vector $D$ mesons and with the octet and decuplet baryons is considered. The leading two-body counter terms involving two baryon fields and two $D$ meson fields are constructed in the open-charm sector. There are 26 terms. A combined expansion in the inverse of the charm quark mass and in the inverse of the number of colors provides sum rules that reduce the number of free parameter down to 5 only. Our result shows the feasibility of a systematic computation of the open-charm baryon spectrum based on coupled-channel dynamics.
description: 19 pages
No peaks without valleys: The stable mass transfer channel for gravitational-wave sources in light of the neutron star-black hole mass gap
Creators: name: van Son, L. A. C.
name: de Mink, S. E.
name: Renzo, M.
name: Justham, S.
name: Zapartas, E.
name: Breivik, K.
name: Callister, T.
name: Farr, W. M.
name: Conroy, C.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Gravitational-wave (GW) detections are starting to reveal features in the mass distribution of double compact objects. The lower end of the black hole (BH) mass distribution is especially interesting as few formation channels contribute here and because it is more robust against variations in the cosmic star formation than the high mass end. In this work we explore the stable mass transfer channel for the formation of GW sources with a focus on the low-mass end of the mass distribution. We conduct an extensive exploration of the uncertain physical processes that impact this channel. We note that, for fiducial assumptions, this channel reproduces the peak at $\sim9 \mathrm{M_{\odot}}$ in the GW-observed binary BH mass distribution remarkably well, and predicts a cutoff mass that coincides with the upper edge of the purported neutron star BH mass gap. The peak and cutoff mass are a consequence of unique properties of this channel, namely (1) the requirement of stability during the mass transfer phases, and (2) the complex way in which the final compact object masses scale with the initial mass. We provide an analytical expression for the cutoff in the primary component mass and show that this adequately matches our numerical results. Our results imply that selection effects resulting from the formation channel alone can provide an explanation for the purported neutron star--BH mass gap in GW detections. This provides an alternative to the commonly adopted view that the gap emerges during BH formation.
description: Accepted for publication in ApJ associated code is available at https://github.com/LiekeVanSon/LowMBH_and_StableChannel
Phase-Retrieval in Shift-Invariant Spaces with Gaussian Generator
Creators: name: Gröchenig, Karlheinz
Publisher: name: arXiv
Year: 2019
Subjects: subject: Complex Variables (math.CV)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 94A12, 42C15, 49N30

description: We study the problem of recovering a function of the form $f(x) = \sum _{k\in \mathbb{Z} } c_k e^{-(x-k)^2}$ from its phaseless samples $|f(λ)|$ on some arbitrary countable set $Λ\subseteq \mathbb{R} $. For real-valued functions this is possible up to a sign for every separated set with Beurling density $D^-(Λ) >2$. This result is sharp. For complex-valued functions we find all possible solutions with the same phaseless samples.
Tracing of intracellular pH in cancer cells in response to Taxol treatment
Creators: name: Druzhkova, Irina
name: Lukina, Maria
name: Dudenkova, Varvara
name: Ignatova, Nadezhda
name: Snopova, Ludmila
name: Gavrina, Alena
name: Shimolina, Lyubov
name: Zagaynova, Elena
name: Shirmanova, Marina
Publisher: name: Taylor & Francis
Year: 2021
Subjects: subject: Biophysics
subject: Medicine
subject: Cell Biology
subject: Genetics
subject: FOS: Biological sciences
subject: Molecular Biology
subject: Physiology
subject: Pharmacology
subject: Developmental Biology
subject: Cancer
subject: Plant Biology

description: Genetically encoded pH-sensors are the promising instrument for intracellular pH (pHi) registration. In tumor tissue the reversed pH gradient is known to be the important hallmark of cancer and regulator of tumor response on chemotherapy. However the effect of chemotherapeutic drugs on the pHi of tumor cells is largely unknown. Here we using genetically encoded ratiometric pH-sensor SypHer2 were able to monitor pHi in vitro in cell monolayer and tumor spheroids and in vivo in tumor xenografts. In tumor cell monolayer different pHi dynamic was revealed in the dying cell and division-arrested surviving cells. The treatment effect of taxol varied in monolayer and tumor spheroids and pHi changes were able to reflect these difference. The tend to pHi decrease in respect to taxol in vivo matched with results obtained for the cell monolayer. Also in both cases the cell cycle-arrest was the main treatment effect in contrast to tumor spheroid, where the cell death was the primary result. These findings elucidate the significance of pHi in the mechanisms of taxol action on cervical cancer cells and will be valuable for development of new approaches for cancer treatment.
Highly edge-connected regular graphs without large factorizable subgraphs
Creators: name: Mattiolo, Davide
name: Steffen, Eckhard
Publisher: name: arXiv
Year: 2019
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We construct highly edge-connected $r$-regular graph which do not contain $r-2$ pairwise disjoint perfect matchings. The results partially answer a question stated by Thomassen [Factorizing regular graphs, J. Comb. Theory Ser. B (2019), https://doi.org/10.1016/j.jctb.2019.05.002 (article in press)].
description: 10 pages; submitted for publication
Experimental observation of the optical spin transfer torque
Creators: name: Nemec, P.
name: Rozkotova, E.
name: Tesarova, N.
name: Trojanek, F.
name: De Ranieri, E.
name: Olejnik, K.
name: Zemen, J.
name: Novak, V.
name: Cukr, M.
name: Maly, P.
name: Jungwirth, T.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The spin transfer torque is a phenomenon in which angular momentum of a spin polarized electrical current entering a ferromagnet is transferred to the magnetization. The effect has opened a new research field of electrically driven magnetization dynamics in magnetic nanostructures and plays an important role in the development of a new generation of memory devices and tunable oscillators. Optical excitations of magnetic systems by laser pulses have been a separate research field whose aim is to explore magnetization dynamics at short time scales and enable ultrafast spintronic devices. We report the experimental observation of the optical spin transfer torque, predicted theoretically several years ago building the bridge between these two fields of spintronics research. In a pump-and-probe optical experiment we measure coherent spin precession in a (Ga,Mn)As ferromagnetic semiconductor excited by circularly polarized laser pulses. During the pump pulse, the spin angular momentum of photo-carriers generated by the absorbed light is transferred to the collective magnetization of the ferromagnet. We interpret the observed optical spin transfer torque and the magnetization precession it triggers on a quantitative microscopic level. Bringing the spin transfer physics into optics introduces a fundamentally distinct mechanism from the previously reported thermal and non-thermal laser excitations of magnets. Bringing optics into the field of spin transfer torques decreases by several orders of magnitude the timescales at which these phenomena are explored and utilized.
description: 11 pages, 4 figures
Mixing and entrainment of burned products in high Karlovitz number premixed jet flames
Creators: name: Attili, Antonio
name: Kleinheinz, Konstantin
name: Denker, Dominik
name: Berger, Lukas Konstantin Willi
name: Bisetti, Fabrizio
name: Pitsch, Heinz
Publisher: name: RWTH Aachen University
Year: 2019

description: 9th European Combustion Meeting 2019 : 14-17 April, 2019, Lisboa, Portugal : book of abstracts / edited by: Sandrina Pereira and Mário Costa ; organisers: Portuguese Section of the Combustion Institute, Instituto Superior Técnico (University of Lisboa, Portugal) 9th European Combustion Meeting, ECM 2019, Lisbon, Portugal, 14 Apr 2019 - 17 Apr 2019; Lisboa : IST - Técnico Lisboa (2019).
description: Published by IST - Técnico Lisboa, Lisboa
Edge colorings and circular flows on regular graphs
Creators: name: Mattiolo, Davide
name: Steffen, Eckhard
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: 05C21

description: Let $ϕ_c(G)$ be the circular flow number of a bridgeless graph $G$. In [Edge-colorings and circular flow numbers of regular graphs, J. Graph Theory 79 (2015) 1-7] it was proved that, for every $t \geq 1$, $G$ is a bridgeless $(2t+1)$-regular graph with $ϕ_c(G) \in \{2+\frac{1}{t}, 2 + \frac{2}{2t-1}\}$ if and only if $G$ has a perfect matching $M$ such that $G-M$ is bipartite. This implies that $G$ is a class 1 graph. For $t=1$, all graphs with circular flow number bigger than 4 are class 2 graphs. We show for all $t \geq 1$, that $2 + \frac{2}{2t-1} = \inf \{ ϕ_c(G)\colon G \text{ is a } (2t+1) \text{-regular class } 2 \text{ graph}\}$. This was conjectured to be true in [Edge-colorings and circular flow numbers of regular graphs, J. Graph Theory 79 (2015) 1-7]. Moreover we prove that $\inf\{ ϕ_c(G)\colon G $ is a $ (2t+1)$-regular class $1$ graph with no perfect matching whose removal leaves a bipartite graph$ \} = 2 + \frac{2}{2t-1}$. We further disprove the conjecture that every $(2t+1)$-regular class $1$ graph has circular flow number at most $2+\frac{2}{t}$.
description: 17 pages; submitted for publication
An alternative origin for debris rings of planetesimals
Creators: name: Nayakshin, Sergei
name: Cha, Seung-Hoon
Publisher: name: arXiv
Year: 2012
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Core Accretion, the most widely accepted scenario for planet formation, postulates existence of km-sized solid bodies, called planetesimals, arranged in a razor-thin disc in the earliest phases of planet formation. In the Tidal Downsizing hypothesis, an alternative scenario for formation of planets, grain growth, sedimentation and formation of planetary cores occur inside dense and massive gas clumps formed in the outer cold disc by gravitational instability. As a clump migrates inward, tidal forces of the star remove all or most of the gas from the clump, downsizing it to a planetary mass body. Here we argue that such a clump may form not only the planetary core but also numerous smaller bodies. As an example, we consider the simplest case of bodies on circular orbits around the planetary core in the centre of the gas clump. Bodies smaller than 1 km suffer a strong enough aerodynamic drag, spiral in and accrete onto the solid core rapidly; bodies in the planetesimal size range lose their centrifugal support very slowly. We find that planetesimals orbiting the protoplanetary core closely remain gravitationally bound to it; these may be relevant to formation of satellites of giant planets. Planetesimals on more distant orbits within the host clump are unbound from the protoplanet and are set on mildly eccentric heliocentric orbits, generically forming wide rings. These may correspond to debris discs around main sequence stars and the Kuiper belt in the Solar System. For the latter in particular, our hypothesis naturally explains the observed sharp outer edge and the "mass deficit" of the Kuiper belt.
description: Submitted to MNRAS
Analysis of Carbodeon's Nicanite®
Creators: name: Bojdys, Michael J.
Publisher: name: Zenodo
Year: 2017
Subjects: carbon nitride
g-C3N4
C3N4
Melon
photocatalysis

description: This data is featured in the supporting information section of “Functional carbon nitride materials — design strategies for electrochemical devices” by Bojdys et al. in Nature Reviews Materials 2017, Article number: 17030 (2017), DOI: 10.1038/natrevmats.2017.30 So-called “graphitic carbon nitride” or “g-C3N4” is actually a linear polymer. Here, we analyse a commercially available product that doesn’t quite hold up to scrutiny. The here-presented physical data was compiled in March 2013 (internal report with permission from the University of Liverpool, Department of Chemistry, UK). It should serve as a sanity-check to facilitate quick identification of (C6N8) melon-type samples and aid in phase identification even in tricky cases: e.g. melon is chemically and physically indistinguishable from Nicanite® that was marketed as a “high purity, graphitic carbon nitride” by Carbodeon.
A deep study of A399-401: An application for wide-field facet calibration
Creators: name: de Jong, J. M. G. H. J.
name: van Weeren, R. J.
name: Botteon, A.
name: Oonk, J. B. R.
name: Brunetti, G.
name: Shimwell, T. W.
name: Cassano, R.
name: Röttgering, H. J. A.
name: Tasse, C.
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We examine the particle acceleration mechanism in the Mpc-scale bridge between Abell 399 and Abell 401 and assess in particular if the synchrotron emission originates from first-order or second-order Fermi re-acceleration. We use deep (~40 hours) LOw-Frequency ARray (LOFAR) observations from Abell 399 and Abell 401 and apply improved direction-dependent calibration to produce deep radio images at three different resolutions at 144 MHz. With a point-to-point analysis we find in the bridge trends between the radio emission from our new maps and X-ray emission from an XMM Newton observation. By analyzing our observations and results, we argue that second-order Fermi re-acceleration is currently the most favoured process to explain the emission from the radio bridge, where past AGN activity may be responsible for the supply of fossil plasma needed for in-situ re-acceleration. The radio halos from Abell 401 and Abell 399 are also consistent with a second-order Fermi re-acceleration model.
Quantum Element Method for Simulation of Quantum Eigenvalue Problems
Creators: name: Cheng, Ming-C.
Publisher: name: arXiv
Year: 2020
Subjects: subject: Computational Physics (physics.comp-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: A previously developed quantum reduced-order model is revised and applied, together with the domain decomposition, to develop the quantum element method (QEM), a methodology for fast and accurate simulation of quantum eigenvalue problems. The concept of the QEM is to partition the simulation domain of a quantum eigenvalue problem into smaller subdomains that are referred to as elements. These elements could be the building blocks for quantum structures of interest. Each of the elements is projected onto a functional space represented by a reduced order model, which leads to a quantum Hamiltonian equation in the functional space for each element. The basis functions in this study is generated from proper orthogonal decomposition (POD). To construct a POD model for a large domain, these projected elements are combined together, and the interior penalty discontinuous Galerkin method is applied to stabilize the numerical solution and to achieve the interface continuity. The POD is able to optimize the basis functions (or POD modes) specifically tailored to the geometry and parametric variations of the problem and can therefore substantially reduce the degree of freedom (DoF) needed to solve the Schrödinger equation. The proposed multi-element POD model (or QEM) is demonstrated in several quantum-well structures with a focus on understanding how to achieve accurate prediction of WFs with a small numerical DoF. It has been shown that the QEM is able to achieve a substantial reduction in the DoF with a high accuracy beyond the conditions accounted for in the training of the POD modes.
Local semicircle law at the spectral edge for Gaussian $β$-ensembles
Creators: name: Wong, Percy
Publisher: name: arXiv
Year: 2011
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: We study the local semicircle law for Gaussian $β$-ensembles at the edge of the spectrum. We prove that at the almost optimal level of $n^{-2/3+ε}$, the local semicircle law holds for all $β\geq 1$ at the edge. The proof of the main theorem relies on the calculation of the moments of the tridiagonal model of Gaussian $β$-ensembles up to the $p_n$-moment where $p_n = O(n^{2/3-ε})$. The result is the analogous to the result of Sinai and Soshnikov for Wigner matrices, but the combinatorics involved in the calculations are different.
description: 16 pages, 2 figures
Accretion Disc Wind Variability in the States of the Microquasar GRS 1915+105
Creators: name: Neilsen, Joseph
name: Petschek, Andrew J.
name: Lee, Julia C.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Continuing our study of the role and evolution of accretion disc winds in the microquasar GRS 1915+105, we present high-resolution spectral variability analysis of the beta and gamma states with the Chandra High Energy Transmission Grating Spectrometer. By tracking changes in the absorption lines from the accretion disc wind, we find new evidence that radiation links the inner and outer accretion discs on a range of time-scales. As the central X-ray flux rises during the high-luminosity gamma state, we observe the progressive over-ionization of the wind. In the beta state, we argue that changes in the inner disc leading to the ejection of a transient 'baby jet' also quench the highly-ionized wind from the outer disc. Our analysis reveals how the state, structure, and X-ray luminosity of the inner accretion disc all conspire to drive the formation and variability of highly-ionized accretion disc winds.
description: Accepted for publication in MNRAS. 11 pages, 7 figures, uses mn2e.cls. Comments welcome
Improved asteroseismic inversions for red-giant surface rotation rates
Creators: name: Ahlborn, F.
name: Bellinger, E. P.
name: Hekker, S.
name: Basu, S.
name: Mokrytska, D.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Asteroseismic observations of internal stellar rotation have indicated a substantial lack of angular momentum transport in theoretical models of subgiant and red-giant stars. Accurate core and surface rotation rate measurements are therefore needed to constrain internal transport processes included in the models. We eliminate substantial systematic errors of asteroseismic surface rotation rates found in previous studies. We propose a new objective function for the Optimally Localized Averages method of rotational inversions for red-giant stars, which results in more accurate envelope rotation rate estimates obtained from the same data. We use synthetic observations from stellar models across a range of evolutionary stages and masses to demonstrate the improvement. We find that our new inversion technique allows us to obtain estimates of the surface rotation rate that are independent of the core rotation. For a star at the base of the red-giant branch, we reduce the systematic error from about 20% to a value close to 0, assuming constant envelope rotation. We also show the equivalence between this method and the method of linearised rotational splittings. Our new rotational inversion method substantially reduces the systematic errors of red-giant surface rotation rates. In combination with independent measures of the surface rotation rate, this will allow better constraints to be set on the internal rotation profile. This will be a very important probe to further constrain the internal angular momentum transport along the lower part of the red-giant branch.
description: 17 pages, 22 figures, accepted for publication in Astronomy and Astrophysics
Rationalizing Rational Expectations: Characterization and Tests
Creators: name: D'Haultfoeuille, Xavier
name: Gaillac, Christophe
name: Maurel, Arnaud
Publisher: name: arXiv
Year: 2020
Subjects: subject: Econometrics (econ.EM)
subject: FOS: Economics and business

description: In this paper, we build a new test of rational expectations based on the marginal distributions of realizations and subjective beliefs. This test is widely applicable, including in the common situation where realizations and beliefs are observed in two different datasets that cannot be matched. We show that whether one can rationalize rational expectations is equivalent to the distribution of realizations being a mean-preserving spread of the distribution of beliefs. The null hypothesis can then be rewritten as a system of many moment inequality and equality constraints, for which tests have been recently developed in the literature. The test is robust to measurement errors under some restrictions and can be extended to account for aggregate shocks. Finally, we apply our methodology to test for rational expectations about future earnings. While individuals tend to be right on average about their future earnings, our test strongly rejects rational expectations.
description: 59 pages, 25 pages of supplement
Handsets Malware Threats and Facing Techniques
Creators: name: Elfattah, Marwa M. A.
name: Youssif, Aliaa A. A.
name: Sarhan, Ebada
Publisher: name: arXiv
Year: 2012
Subjects: subject: Cryptography and Security (cs.CR)
subject: FOS: Computer and information sciences

description: Nowadays, mobile handsets combine the functionality of mobile phones and PDAs. Unfortunately, mobile handsets development process has been driven by market demand, focusing on new features and neglecting security. So, it is imperative to study the existing challenges that facing the mobile handsets threat containment process, and the different techniques and methodologies that used to face those challenges and contain the mobile handsets malwares. This paper also presents a new approach to group the different malware containment systems according to their typologies.
description: 7 pages
Spin and Valley Hall effects induced by asymmetric interparticle scattering
Creators: name: Glazov, M. M.
name: Golub, L. E.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We develop the theory of the spin and valley Hall effects in two-dimensional systems caused by asymmetric -- skew -- scattering of the quasiparticles. The collision integral is derived in the third order in the particle-particle interaction with account for the spin-orbit coupling both for bosons and fermions. It is shown that the scattering asymmetry appears only in the processes where the interaction between the particles in the initial and intermediate state is present. We show that for degenerate electrons or nondegenerate particles the spin and valley currents induced by interparticle collisions are suppressed with their steady-state values being proportional to the squared temperature or density, respectively. Our results imply non-Fermi liquid properties of electrons in the presence of electron-electron skew scattering. Strong deviations from conventional picture of interparticle scattering are also demonstrated for the skew scattering of two-dimensional degenerate bosons, e.g. excitons or exciton polaritons: The spin or valley current of degenerate bosons contains the enhancement factor exponentially growing with increase in the particle density.
description: 7+6 pages, 2 figures. For the Physical Review B special issue "Spin-Coherent Phenomena in Semiconductors" in honor of E. I. Rashba
Universal model for electron thermal-field emission from two-dimensional semimetals
Creators: name: Ang, L. K.
name: Ang, Yee Sin
name: Lee, Ching Hua
Publisher: name: arXiv
Year: 2020
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Applied Physics (physics.app-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We present the theory of out-of-plane (or vertical) electron thermal-field emission from 2D semimetals. We show that the current-voltage-temperature characteristic is well-captured by a universal scaling relation applicable for broad classes of 2D semimetals, including graphene and its few-layer, nodal point semimetal, Dirac semimetal at the verge of topological phase transition and nodal line semimetal. Here an important consequence of the universal emission behavior is revealed: in contrast to the common expectation that band topology shall manifest differently in the physical observables, band topologies in two spatial dimension are indistinguishable from each others and bear no special signature in the electron emission characteristics. Our findings represent the quantum extension of the universal semiclassical thermionic emission scaling law in 2D materials, and provide the theoretical foundations for the understanding of electron emission from cathode and charge interface transport for the design of 2D-material-based vacuum nanoelectronics.
description: 9 pages, 2 figures, 2 tables
SM extension with a gauged flavor $U(1)_F$ symmetry
Creators: name: Tavartkiladze, Zurab
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: An extension of the Standard Model with anomaly free $U(1)_F$ flavor symmetry is studied in this paper. With this extension and the addition of the right-handed neutrino states, the solution of anomaly free charge assignments is found, which gives appealing texture zero and hierarchical Yukawa matrices. This gives us a natural understanding of the hierarchies between charged fermion masses and Cabibbo-Kobayashi-Maskawa (CKM) matrix elements. Neutrino Dirac and Majorana coupling matrices also have desirable structures leading to successful neutrino oscillations with inverted neutrino mass ordering. Other interesting implications of the presented scenario are also discussed.
description: Matched to Phys. Rev. D version
Formation, distribution, and IR emission of dust in the clumpy ejecta of Type II-P core-collapse supernovae, in isotropic and anisotropic scenarios
Creators: name: Sarangi, Arkaprabha
Publisher: name: arXiv
Year: 2022
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Large discrepancies are found between observational estimates and theoretical predictions when exploring the characteristics of dust formed in the ejecta of core-collapse supernovae. We revisit the scenario of dust production in typical supernova ejecta in the first 3000 days after explosion, with an improved understanding of the evolving physical conditions and the distribution of the clumps. The generic, nonuniform distribution of dust within the ejecta was determined and using that, the relevant opacities and fluxes were calculated. The dependence of the emerging fluxes on the viewing angle was estimated for an anisotropic, ellipsoidal geometry of the ejecta that imitate SN 1987A. We model the He-core from the center to its outer edge as 450 stratified, clumpy, annular shells, uniquely identified by their distinct velocities and characterized by their variations in abundances, densities, and gas and dust temperatures. We find that the formation of dust starts between day 450 and day 550 post-explosion, and it continues until about day 2800, although the first 1600 days are the most productive. The total dust mass evolves from about 10^-5 Msun at day 500 to 10^-3 Msun at day 800, finally saturating at about 0.06 Msun. The masses of the O-rich dust (silicates, alumina) dominates the C-rich dust (amorphous carbon, silicon carbide) at all times; the formation of carbon dust is delayed beyond 2000 days post-explosion. We show that the opacities are largest between days 800 and 1600, and the characteristic spectral features of O-rich dust species are suppressed at those times. The fluxes emerging along the smallest axes of the ellipsoidal ejecta are found to be the most obscured, while a viewing angle between 16 and 21 degrees with that axis appears to be in the best agreement with the fluxes from SN 1987A at days 615 and 775.
description: Published in Astronomy & Astrophysics (A&A)
An analytic generalization of the Catalan numbers and its integral representation
Creators: name: Li, Wen-Hui
name: Cao, Jian
name: Niu, Da-Wei
name: Zhao, Jiao-Lian
name: Qi, Feng
Publisher: name: arXiv
Year: 2020
Subjects: subject: Combinatorics (math.CO)
subject: FOS: Mathematics
subject: Primary 05A15, Secondary 11B75, 11B83, 26A09, 30E20, 41A58

description: In the paper, the authors analytically generalize the Catalan numbers in combinatorial number theory, establish an integral representation of the analytic generalization of the Catalan numbers by virtue of Cauchy's integral formula in the theory of complex functions, and point out potential directions to further study.
description: 14 pages, 1 figure
Extended Kramers-Moyal analysis applied to optical trapping
Creators: name: Honisch, Christoph
name: Friedrich, Rudolf
name: Hörner, Florian
name: Denz, Cornelia
Publisher: name: arXiv
Year: 2012
Subjects: subject: Data Analysis, Statistics and Probability (physics.data-an)
subject: FOS: Physical sciences

description: The Kramers-Moyal analysis is a well established approach to analyze stochastic time series from complex systems. If the sampling interval of a measured time series is too low, systematic errors occur in the analysis results. These errors are labeled as finite time effects in the literature. In the present article, we present some new insights about these effects and discuss the limitations of a previously published method to estimate Kramers-Moyal coefficients at the presence of finite time effects. To increase the reliability of this method and to avoid misinterpretations, we extend it by the computation of error estimates for estimated parameters using a Monte Carlo error propagation technique. Finally, the extended method is applied to a data set of an optical trapping experiment yielding estimations of the forces acting on a Brownian particle trapped by optical tweezers. We find an increased Markov-Einstein time scale of the order of the relaxation time of the process which can be traced back to memory effects caused by the interaction of the particle and the fluid. Above the Markov-Einstein time scale, the process can be very well described by the classical overdamped Markov model for Brownian motion.
description: 14 pages, 18 figures
The propagation of relativistic jets in external media
Creators: name: Bromberg, Omer
name: Nakar, Ehud
name: Piran, Tsvi
name: Sari, Re'em
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Relativistic jets are ubiquitous in astrophysical systems that contain compact objects. They transport large amounts of energy to large distances from the source, and their interaction with the ambient medium has a crucial effect on the evolution of the system. The propagation of the jet is characterized by the formation of a shocked "head" at the front of the jet which dissipates the jet's energy and a cocoon that surrounds the jet and potentially collimates it. We present here a self consistent, analytic model that follows the evolution of the jet and its cocoon, and describes their interaction. We show that the critical parameter that determines the properties of the jet-cocoon system is the dimensionless ratio between the jet's energy density and the rest-mass energy density of the ambient medium. This parameter, together with the jet's injection angle, also determines whether the jet is collimated by the cocoon or not. The model is applicable to relativistic, unmagnetized, jets on all scales and may be used to determine the conditions in AGNs jets as well as in GRBs or microquasars. It shows that AGN and microquasar jets are hydrodynamically collimated due to the interaction with the ambient medium, while GRB jets can be collimated only inside a star and become uncollimated once they breakout.
description: 35 pages, 4 figures
Maximal nilpotent complex structures
Creators: name: Gao, Qin
name: Zhao, Quanting
name: Zheng, Fangyang
Publisher: name: arXiv
Year: 2020
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics

description: Let the pair $(\mathfrak{g},J)$ be a nilpotent Lie algebra $\mathfrak{g}$ (NLA for short) endowed with a nilpotent complex structure $J$. In this paper, motivated by a question in the work of Cordero, Fernández, Gray and Ugarte, we prove that $2\leq ν(J) \leq 3$ for $(\mathfrak{g},J)$ when $ν(\mathfrak{g})=2$, where $ν(\mathfrak{g})$ is the step of $\mathfrak{g}$ and $ν(J)$ is the unique smallest integer such that $\mathfrak{a}(J)_{ν(J)}=\mathfrak{g}$ as in Definition 1 and 8 of the paper by Cordero, Fernández, Gray and Ugarte. When $ν(\mathfrak{g})=3$, for arbitrary $n \geq 3$, there exists a pair $(\mathfrak{g},J)$ such that $ν(J)=\dim_{\mathbb{C}}\mathfrak{g}=n$, for which we call the $J$ in the pair $(\mathfrak{g},J)$, satisfying $ν(J)=\dim_{\mathbb{C}}\mathfrak{g}=n$, a maximal nilpotent (MaxN for short) complex structure. The algebraic dimension of a nilmanifold endowed with a left invariant MaxN complex structure is discussed. Furthermore, a structure theorem is proved for the pair $(\mathfrak{g},J)$, where $ν(\mathfrak{g})=3$ and $J$ is a MaxN complex structure.
Higher-order optical resonance node detection of integrated disk microresonator
Creators: name: Ostrowski, M.
name: Pignalosa, P.
name: Smith, H.
name: Yi, Yasha
Publisher: name: arXiv
Year: 2011
Subjects: subject: Optics (physics.optics)
subject: Biological Physics (physics.bio-ph)
subject: FOS: Physical sciences

description: We have demonstrated higher-order optical resonance node detection by using an integrated disk microresonator from through port of the coupling bus waveguide. In addition to the fundamental mode, the disk resonator has higher-order whispering gallery modes. The excited second-order higher-order mode has a node at the position where the electromagnetic energy of the fundamental mode is close to a maximum. This high resolution measurement of optical resonance mode profile has a variety of applications for optical sensing and detection. The self-referencing characteristics of the two optical resonance modes have potential to achieve optical detection independent of external perturbation, such as temperature change.
Marcinkiewicz-Zygmund Inequalities for Polynomials in Bergmann and Hardy Spaces
Creators: name: Gröchenig, Karlheinz
name: Ortega-Cerdà, Joaquim
Publisher: name: arXiv
Year: 2020
Subjects: subject: Complex Variables (math.CV)
subject: Functional Analysis (math.FA)
subject: FOS: Mathematics
subject: 30E05, 30H20, 41A10, 42B30

description: We study the relationship between sampling sequences in infinite dimensional Hilbert spaces of analytic functions and Marcinkiewicz-Zygmund inequalities in subspaces of polynomials. We focus on the study of the Hardy space and the Bergman space in one variable because they provide two settings with a strikingly different behavior.
description: 23 pp