cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Residual entanglement and sudden death: A direct connection
Creators: name: Junior, J. G. Oliveira
name: de Faria, J. G. Peixoto
name: Nemes, M. C.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We explore the results of [V. Coffman, et al., Phys. Rev. A 61 (2000) 052306] derived for general tripartite states in a dynamical context. We study a class of physically motivated tripartite systems. We show that whenever entanglement sudden death occurs in one of the partitions residual entanglement will appear. For fourpartite systems however, the appearance of residual entanglement is not conditioned by sudden death of entanglement. We can only say that if sudden death of entanglement occurs in some partition there will certainly be residual entanglement.
description: 8 pages, 6 figures, to appear in PLA, DOI information: 10.1016/j.physleta.2011.10.020
Boundless revolution : global maoism and communist movements in southeast Asia, 1949-1979
Creators: name: Galway, Matthew
Publisher: name: University of British Columbia
Year: 2017

description: This dissertation argues that Chairman Mao Zedong’s written texts, his thought (毛澤東思想, Máo Zédōng Sīxiǎng), and the institutions that he envisioned and established in China formed an ideological system, which evolved through several stages until manifesting outside China. In relevant scholarship thus far, due attention has not been paid to the complex interplay between Maoism and the intellectual foundations of Communist movements in Cambodia, the Philippines, and Indonesia. The dissertation applies a theoretical framework that expands upon Edward Said’s concept of “Traveling Theory,” which outlines three principal conditions of production, transmission, and reception by introducing three subsidiary problems of reception, adaptation, and implementation to uncover how Maoism came to be and, subsequently, globalized. Philip Kuhn’s theory of the ideal socio-contextual “fit” of exogenous ideas allows us to uncover how one receives, interprets, and adapts exogenous ideas. Kenneth Jowitt’s understanding of Leninism allows us to understand the essentials of implementation, whereby an adapted theory is put into practice by a regime tinged by the outside ideology. By focusing on Said’s triad, we may approach the problems of reception of radical thought in Southeast Asia, its adaptation into different thought streams, and its implementation under Maoist or Marxist-Leninist courses. Radical intellectuals from these countries who became Communists were networked individuals within a situated thinking responding to crises by taking a radical turn. Their reception of radical thought led to the original idea’s transformation into a variant that was congruent with contemporary norms. As a genealogy of the social experiences and a close textual exegesis of political writings and pronouncements by the Cambodian Paris Group (Hou Yuon, Khieu Samphan, Hu Nim, and Saloth Sar), José Maria Sison, and Dipa Nusantara Aidit ultimately reveals, their reception of radical thought from outside their milieus was dialectical in nature. They spoke back, investing Maoism with new signification, without abandoning the universality of the original theory (its Russian or its Chinese accretions), which stood as an alternative global model for waging national revolution and socialist transformation. In this way, this empirical study contributes to a better understanding of radical thought.
Pion generalized parton distribution from lattice QCD
Creators: name: Chen, Jiunn-Wei
name: Lin, Huey-Wen
name: Zhang, Jian-Hui
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: We present the first lattice calculation of the valence-quark generalized parton distribution (GPD) of the pion using the large-momentum effective theory (LaMET) approach. We focus on the zero-skewness limit, where the GPD has a probability-density interpretation in the longitudinal Bjorken xand the transverse impact-parameter distributions. Our calculation is done using clover valence fermions on an ensemble of gauge configurations with 2 +1 +1flavors (degenerate up/down, strange and charm) of highly im-proved staggered quarks (HISQ) with lattice spacing a≈0.12fm, box size L ≈3fm and pion mass mπ≈310MeV. The parton distribution function and the form factor are reproduced as special limits of the GPD as expected. Due to the large errors, this exploratory study does not show a clear preference among different model assumptions about the kinematic dependence of the GPD. To discriminate betweenthese assumptions, future studies using higher-statistics data will be crucial.
Universal renormalons in principal chiral models
Creators: name: Bruckmann, Falk
name: Puhr, Matthias
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: Perturbative expansions in many physical systems yield “only” asymptotic series which are not even Borel resummable. Interestingly, the corresponding ambiguities point to nonperturbative physics. We numerically verify this renormalon mechanism for the first time in two-dimensional sigma models, that, like four-dimensional gauge theories, are asymptotically free and generate a strong scale through dimensional transmutation. We perturbatively expand the energy through a numerical version of stochastic quantization. In contrast to the first energy coefficients, the high-order coefficients are independent on the rank of the model. Technically, they require a sophisticated analysis of finite volume effects and the continuum limit of the discretized model. Although the individual coefficients do not grow factorially (yet), but rather decrease strongly, the ratios of consecutive coefficients clearly obey the renormalon asymptotics.
title: Описание методики моделирования симметричной тепловой трубы с дефектом
Creators: name: Филипченко, Николай
Publisher: name: Новгородский государственный университет имени Ярослава Мудрого (НовГУ)
Year: 2021

description: В ходе данной работы описан общий подход к моделированию тепловых труб с дефектами. В статье рассматривается тепловая модель, нацеленная на симуляцию тепловизионного метода контроля качества тепловых труб в программном обеспечении «Elcutstudent 6.3». Результаты моделирования представлены в виде графиков распределения параметров изотермы с течением времени, визуализация температурного поля в момент
прохождения дефекта.
Chemical and Kinematic Analysis of CN-strong  Metal-poor Field Stars in LAMOST
Creators: name: Tang, Baitian
name: Liu, Chao
name: Fernandez-Trincado, Jose
name: Geisler, Doug
Publisher: name: Zenodo
Year: 2019

description: The large amount of chemical and kinematic information available in large spectroscopic surveys have inspired the search for chemical anomaly stars in the field. Though these metal-poor stars ([Fe/H]<-1) are commonly enriched in nitrogen, their detailed spatial, kinematic, and chemical distributions suggest that various groups of chemical anomaly stars may exist, thus their origin is still a mystery.  To study these N-rich stars statistically, we show our effort of increasing the sample size by identifying new CN-strong stars with LAMOST DR3. We use CN-CH bands around 4000 A to find CN-strong stars, and further separate them into CH-normal stars and CH-strong stars. The chemical abundances from our data-driven software and APOGEE DR 14 suggest that most CH-normal stars are N-rich, while CH-strong stars may be carbon stars. The kinematics of our CN-strong CH-normal stars indicate a substantial fraction of these stars are retrograding, poin pointing to a possible extragalactic origin.
Analytical Computation of Critical Exponents in Several Holographic Superconductors
Creators: name: Zeng, Hua-Bi
name: Gao, Xin
name: Jiang, Yu
name: Zong, Hong-Shi
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: It is very interesting that all holographic superconductors, such as s-wave, p-wave and d-wave holographic superconductors, show the universal mean-field critical exponent 1/2 at the critical temperature, just like Gindzburg-Landau (G-L) theory for second order phase transitions. Now it is believed that the universal critical exponents appear because the dual gravity theory is classic in the large $N$ limit. However, even in the large $N$ limit there is an exception called "non-mean-field theory": an extension of the s-wave model with a cubic term of the charged scalar field shows a different critical exponent 1. In this paper, we try to use analytical methods to obtain the critical exponents for these models to see how the properties of the gravity action decides the appearance of the mean-field behaviors. It will be seen that just like the G-L theory, it is the fundamental symmetries rather than the detailed parameters of the bulk theory that lead to the universal properties of the holographic superconducting phase transition. The feasibility of the called "non-mean-field theory" is also discussed.
description: 20 pages, accepted by JHEP, some interpretation added
Optimal Visual Search with Highly Heuristic Decision Rules
Creators: name: Zhang, Anqi
name: Geisler, Wilson S.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Applications (stat.AP)
subject: FOS: Biological sciences
subject: FOS: Computer and information sciences

description: Visual search is a fundamental natural task for humans and other animals. We investigated the decision processes humans use in covert (single-fixation) search with briefly presented displays having well-separated potential target locations. Performance was compared with the Bayesian-optimal decision process under the assumption that the information from the different potential target locations is statistically independent. Surprisingly, humans performed slightly better than optimal, despite humans' substantial loss of sensitivity in the fovea (foveal neglect), and the implausibility of the human brain replicating the optimal computations. We show that three factors can quantitatively explain these seemingly paradoxical results. Most importantly, simple and fixed heuristic decision rules reach near optimal search performance. Secondly, foveal neglect primarily affects only the central potential target location. Finally, spatially correlated neural noise can cause search performance to exceed that predicted for independent noise. These findings have broad implications for understanding visual search tasks and other identification tasks in humans and other animals.
Neutrinos from WIMP annihilation in the Sun : Implications of a self-consistent model of the Milky Way's dark matter halo
Creators: name: Kundu, Susmita
name: Bhattacharjee, Pijushpani
Publisher: name: arXiv
Year: 2011
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: Upper limits on the spin-independent (SI) as well as spin-dependent (SD) elastic scattering cross sections of WIMPs with protons, imposed by the Super-Kamiokande (S-K) upper limit on the neutrino flux from WIMP annihilation in the Sun, and their compatibility with the "DAMA-compatible" regions of the WIMP parameter space within which the annual modulation signal observed by the DAMA/LIBRA experiment is compatible with the null results of other direct detection experiments, are studied within the frame work of a self-consistent model of the finite-size dark matter (DM) halo of the Galaxy, the parameters of which are determined by a fit to the rotation curve data of the Galaxy. We find that the S-K implied upper limits on the WIMP-proton elastic cross section as a function of WIMP mass impose stringent restrictions on the branching fractions of the various WIMP annihilation channels. For SI interaction, while the S-K upper limits are consistent with the DAMA-compatible region of the WIMP parameter space if the WIMPs annihilate dominantly to $\bbarb$\ and/or $\cbarc$, portions of the DAMA-compatible region can be excluded if WIMP annihilations to $\tautau$ and $ν\anu$ occur at larger than ~ 10% and 0.1% levels, respectively. For SD interaction, the restrictions on the possible annihilation channels are much more stringent, essentially ruling out the DAMA-compatible region of the WIMP parameter space if the relatively low-mass ($\sim$ 2 -- 20 GeV) WIMPs under consideration annihilate predominantly to any mixture of $\bbarb$, \ $\cbarc$, \ $\tautau$, \ and $ν\anu$ final states.
description: Replaced with revised version; Latest published results from Super-Kamiokande incorporated; quantitative limits on the branching fractions of various WIMP annihilation channels become more stringent by factors of 3 - 4; references added; overall conclusions unchanged; 17 pages, Latex, 6 Figures, accepted for publication in Phys. Rev. D
Some properties on the tensor square of Lie algebras
Creators: name: Niroomand, Peyman
Publisher: name: arXiv
Year: 2010
Subjects: subject: Rings and Algebras (math.RA)
subject: FOS: Mathematics
subject: 17B60, 17B99

description: In the present paper we extend and improve the results of \cite{bl, br} for the tensor square of Lie algebras. More precisely, for any Lie algebra $L$ with $L/L^2$ of finite dimension, we prove $L\otimes L\cong L\square L\oplus L\wedge L$ and $Z^{\wedge}(L)\cap L^2=Z^{\otimes}(L)$. Moreover, we show that $L\wedge L$ is isomorphic to derived subalgebra of a cover of $L$, and finally we give a free presentation for it.
description: To appear in J. Algebra Appl. with the small revision
Accurate galaxy sizes and star formation induced galaxy growth with KMOS-3D
Creators: name: Wilman, David
Publisher: name: Zenodo
Year: 2019

description: I will demonstrate our ability to measure the emission line and continuum sizes of galaxies in the KMOS^3D survey at z=0.7-2.7 with a typical accuracy of <~20%, and down to 1/8 of a KMOS pixel. These measurements are essential to characterise the sizes and spatial growth of high redshift galaxies with ground-based seeing data, and require substantial care to be taken to track the source and PSF across long observations spanning multiple epochs. Armed with the results, I will examine the role of star formation in the evolution of galaxies in the size-mass plane, and probe the origin of differences in the spatial growth rate with galaxy properties.
Vorticity from irrotationally forced flow
Creators: name: Del Sordo, Fabio
name: Brandenburg, Axel
Publisher: name: arXiv
Year: 2010
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: In the interstellar medium the turbulence is believed to be forced mostly through supernova explosions. In a first approximation these flows can be written as a gradient of a potential being thus devoid of vorticity. There are several mechanisms that could lead to vorticity generation, like viscosity and baroclinic terms, rotation, shear and magnetic fields, but it is not clear how effective they are, neither is it clear whether the vorticity is essential in determining the turbulent diffusion acting in the ISM. Here we present a study of the role of rotation, shear and baroclinicity in the generation of vorticity in the ISM.
description: 2 pages, 1 figure, to be published in Proceedings of IAU Symp. 271, Astrophysical Dynamics: from Stars to Galaxies, ed. N. Brummell and A.S. Brun, CUP
The Conformal Sector of F-theory GUTs
Creators: name: Heckman, Jonathan J.
name: Vafa, Cumrun
name: Wecht, Brian
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: D3-brane probes of exceptional Yukawa points in F-theory GUTs are natural hidden sectors for particle phenomenology. We find that coupling the probe to the MSSM yields a new class of N = 1 conformal fixed points with computable infrared R-charges. Quite surprisingly, we find that the MSSM only weakly mixes with the strongly coupled sector in the sense that the MSSM fields pick up small exactly computable anomalous dimensions. Additionally, we find that although the states of the probe sector transform as complete GUT multiplets, their coupling to Standard Model fields leads to a calculable threshold correction to the running of the visible sector gauge couplings which improves precision unification. We also briefly consider scenarios in which SUSY is broken in the hidden sector. This leads to a gauge mediated spectrum for the gauginos and first two superpartner generations, with additional contributions to the third generation superpartners and Higgs sector.
description: v2: 51 pages, 2 figures, remark added, typos corrected
Off-diagonal correlators of conserved charges from lattice QCD and how to relate them to experiment
Creators: name: Bellwied, R.
name: Borsányi, S.
name: Fodor, Z.
name: Guenther, J. N.
name: Noronha-Hostler, J.
name: Parotto, P.
name: Pásztor, A.
name: Ratti, C.
name: Stafford, J. M.
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: Like fluctuations, nondiagonal correlators of conserved charges provide a tool for the study of chemical freeze-out in heavy ion collisions. They can be calculated in thermal equilibrium using lattice simulations, and be connected to moments of event-by-event net-particle multiplicity distributions. We calculate them from continuum-extrapolated lattice simulations at μB=0, and present a finite-μB extrapolation, comparing two different methods. In order to relate the grand canonical observables to the experimentally available net-particle fluctuations and correlations, we perform a hadron resonance gas model analysis, which allows us to completely break down the contributions from different hadrons. We then construct suitable hadronic proxies for fluctuation ratios, and study their behavior at finite chemical potentials. We also study the effect of introducing acceptance cuts, and argue that the small dependence of certain ratios on the latter allows for a direct comparison with lattice QCD results, provided that the same cuts are applied to all hadronic species. Finally, we perform a comparison for the constructed quantities for experimentally available measurements from the STAR Collaboration. Thus, we estimate the chemical freeze-out temperature to 165 MeV using a strangeness-related proxy. This is a rather high temperature for the use of the hadron resonance gas; thus, further lattice studies are necessary to provide first principle results at intermediate μB.
Strong companies, weak states : contention, corporate social responsibility, and accountability in the global mining industry
Creators: name: Parker, Stefan Michael
Publisher: name: University of British Columbia
Year: 2017

description: Industrial natural resource extraction is a significant source of conflict among citizens, corporations and states throughout the world. Corporate Social Responsibility (CSR) seeks to reduce the social, political, and environmental concerns of communities affected by natural resource extraction through voluntary corporate actions. However, the provision of CSR goods such as education, healthcare, and environmental protection do not necessarily alleviate the concerns of local communities, and critics of CSR note that it cannot replicate state-led development and regulation. By examining conflict regarding large-scale industrial mining operations in Chile and Peru, current critiques of corporate social responsibility are re-theorized to answer why some communities demand direct corporate accountability rather than more robust state-based accountability. I argue that citizens’ relationships of power with states and corporations have been shaped by their historical experiences of state perpetrated violence. In each case study I explore variation among repertoires of contention employed by citizens in relation to the perceived accountability of corporations and states. Where citizens feel unrepresented or threatened by the state, they may prefer to direct demands for accountability towards a corporation that is claiming to be socially responsible. In so doing, I challenge critiques of CSR-governance that focus on the absence of state-led development. By incorporating mining-affected communities as actors demanding accountability rather than subjects of exploitation, I push towards more complex theories of corporate social responsibility and resource governance more generally.
Kooperation als Lösungsmechanismus? Einordnung und Impulse aus organisationssoziologischer Sicht.
Creators: name: Graf-Schlattmann, Marcel
Publisher: name: Zenodo
Year: 2021
Subjects: Organisationssoziologie
Kooperation
Hochschulforschung

description: Ein organisationssoziologischer Vortrag auf der Herbsttagung des ZKI 2021 zum Thema der hochschulübergreifenden Kooperation.
A New Perspective on ADHD Research: Knowledge Graph Construction with LLMs and Network Based Insights
Creators: name: Otal, Hakan T.
name: Faraone, Stephen V.
name: Canbaz, M. Abdullah
Publisher: name: arXiv
Year: 2024
Subjects: subject: Social and Information Networks (cs.SI)
subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences
subject: I.2.4; I.2.7; J.3
subject: 68T30, 68T50, 92C30

description: Attention-Deficit/Hyperactivity Disorder (ADHD) is a challenging disorder to study due to its complex symptomatology and diverse contributing factors. To explore how we can gain deeper insights on this topic, we performed a network analysis on a comprehensive knowledge graph (KG) of ADHD, constructed by integrating scientific literature and clinical data with the help of cutting-edge large language models. The analysis, including k-core techniques, identified critical nodes and relationships that are central to understanding the disorder. Building on these findings, we curated a knowledge graph that is usable in a context-aware chatbot (Graph-RAG) with Large Language Models (LLMs), enabling accurate and informed interactions. Our knowledge graph not only advances the understanding of ADHD but also provides a powerful tool for research and clinical applications.
description: 12 pages, 2 figures
Leveraging IFU observations to study AGN feedback across cosmic time
Creators: name: Wylezalek, Dominika
Publisher: name: Zenodo
Year: 2019

description: AGN feedback is a standard ingredient in galaxy formation models.  Much of the observational evidence for AGN feedback has been obtained on the basis of IFU observations and the main interaction with the gas seems to be through winds.  By relating feedback signatures in powerful quasars to the sSFR in their hosts, we have found that outflows can indeed suppress star formation in their hosts, consistent with the AGN having a `negative' impact. Feedback signatures seem to be best observable in gas-rich galaxies where the coupling of the AGN-driven wind to the gas is strongest. But AGN signatures and winds can also be easily hidden in the integrated spectrum of a galaxy. Using the SDSS-IV MaNGA survey, we have developed a new AGN selection tailored to IFU data uncovering a more nuanced picture of AGN activity allowing to discover AGN signatures at large distances from the galaxy center. I will also introduce the JWST ERS Program "Q3D" (PI: Wylezalek) which will use the NIRSpec and MIRI IFUs and through which we will study the impact of luminous quasars on their hosts. Our program will provide a scientific dataset of broad interest serving as a pathfinder for JWST in IFU mode.
Thermal phase transition in Yang-Mills matrix model
Creators: name: Bergner, Georg
name: Bodendorfer, Norbert
name: Hanada, Masanori
name: Rinaldi, Enrico
name: Schäfer, Andreas
name: Vranas, Pavlos
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: We study the bosonic matrix model obtained as the high-temperature limit of two-dimensional maximally supersymmetric SU(N) Yang-Mills theory. So far, no consensus about the order of the deconfinement transition in this theory has been reached and this hinders progress in understanding the nature of the black hole/black string topology change from the gauge/gravity duality perspective. On the one hand, previous works considered the deconfinement transition consistent with two transitions which are of second and third order. On the other hand, evidence for a first order transition was put forward more recently. We perform high-statistics lattice Monte Carlo simulations at large N and small lattice spacing to establish that the transition is really of first order. Our findings flag a warning that the required large-N and continuum limit might not have been reached in earlier publications, and that was the source of the discrepancy. Moreover, our detailed results confirm the existence of a new partially deconfined phase which describes non-uniform black strings via the gauge/gravity duality. This phase exhibits universal features already predicted in quantum field theory.
The Galactic Bulge: metallicity and perspective
Creators: name: Rich, R. Michael
name: Johnson, Christian
name: Koch, Andreas
name: Shen, Juntai
Publisher: name: Zenodo
Year: 2019

description: I will briefly review the history of bulge metallicity measurements from early studies to the present, including photometric constraints.  I will consider the upper limit of iron metallicity in the bulge, how the field relates to chemically complex clusters, metallicity gradients, and the question of bimodality.  Recent studies suggest that extremely high metallicities and unusual compositions might be found in Galactic Center stars; I will consider current data in assessing those findings.
Coherent adiabatic transport of atoms in radio-frequency traps
Creators: name: Morgan, T.
name: O'Sullivan, B.
name: Busch, Th.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: Coherent transport by adiabatic passage has recently been suggested as a high-fidelity technique to engineer the centre-of-mass state of single atoms in inhomogenous environments. While the basic theory behind this process is well understood, several conceptual challenges for its experimental observation have still to be addressed. One of these is the difficulty that currently available optical or magnetic micro-trap systems have in adjusting the tunneling rate time-dependently while keeping resonance between the asymptotic trapping states at all times. Here we suggest that both requirements can be fulfilled to a very high degree in an experimentally realistic setup based on radio frequency traps on atom chips. We show that operations with close to 100% fidelity can be achieved and that these systems also allow significant improvements for performing adiabatic passage with interacting atomic clouds.
description: 7 pages, 7 figures
Holographic dark energy in Brans-Dicke cosmology with Granda-Oliveros cut-off
Creators: name: Jamil, Mubasher
name: Karami, Kayoomars
name: Sheykhi, Ahmad
name: Kazemi, E.
name: Azarmi, Z.
Publisher: name: arXiv
Year: 2010
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences

description: Motivated by the recent works of one of us [1,2] we study the holographic dark energy in Brans-Dicke gravity with the Granda-Oliveros cut-off proposed recently in literature. We find out that when the present model is combined with Brans-Dicke field the transition from normal state where $w_D >-1 $ to the phantom regime where $w_D
description: 10 pages, accepted for publication in IJTP
Pool-riffle dynamics in mountain streams : implications for maintenance, formation and equilibrium
Creators: name: Chartrand, Shawn M.
Publisher: name: University of British Columbia
Year: 2017

description: It is common for mountain riverbeds to exhibit a repetitive pattern of topographic lows and highs known respectively as pools and riffles. Pool-riffle structures are ecologically important because salmon rely on them for birth, growth and regeneration, and they are physically important because pool-riffles are observed across diverse landscape settings. A common physical characteristic of pool-riffles is that pool spacing is proportional to channel width, for longitudinal bed slopes that vary by two-orders of magnitude. Furthermore, field, numerical and laboratory based studies observe that pools are colocated with points of channel narrowing, and riffles with points of widening. What is not known, however, is how downstream changes of channel width give rise to, and maintain pool-riffles. The goal of my thesis is to address this knowledge gap, and to specifically build physical understanding for the observed spatial correlation between channel width and pool-riffle architecture. I use field work, laboratory experiments and theory to address this goal. In Chapter 2 I apply non-parametric statistics and self-organizing maps to understand the spatial and temporal character of riffle bed surface texture spanning 11 different sediment mobilizing floods, and conclude that frequent texture adjustment is part of the maintenance process for pool-riffles which exhibit topographic stationarity. I build from this finding in Chapters 3, 4 and 5 with laboratory experiments designed to investigate how pool-riffles form and evolve along variable width channel reaches. In Chapter 4 I conclude that pool-riffle formation is physically driven by two competing timescales which reflect the tendency to build riverbed topography through sediment deposition, vs. the tendency to destroy topography through net particle entrainment. I capture these timescales in a mathematical model I develop using theory with physical scaling. In Chapter 5 I show that the (dis)equilibrium state of pool-riffle evolution is quantitatively described by a competition between two rates which reflect the temporal adjustment of riverbed topography and riverbed surface texture. I conclude that equilibrium, or comparability between the rates of topographic and sediment texture adjustment, is most likely to occur when overall sediment mobility and grain size sorting are relatively high.
Dynamic equivalence between atomic and colloidal liquids
Creators: name: López-Flores, Leticia
name: Mendoza-Méndez, Patricia
name: Sánchez-Díaz, Luis E.
name: Pérez-Ángel, Gabriel
name: Chávez-Páez, Martín
name: Vizcarra-Rendón, Alejandro
name: Medina-Noyola, Magdaleno
Publisher: name: arXiv
Year: 2011
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We show that the kinetic-theoretical self-diffusion coefficient of an atomic fluid plays the same role as the short-time self-diffusion coefficient D_S in a colloidal liquid, in the sense that the dynamic properties of the former, at times much longer than the mean free time, and properly scaled with D_S, will indistinguishable from those of a colloidal liquid with the same interaction potential. One important consequence of such dynamic equivalence is that the ratio D_L/ D_S of the long-time to the short-time self-diffusion coefficients must then be the same for both, an atomic and a colloidal system characterized by the same inter-particle interactions. This naturally extends to atomic fluids a well-known dynamic criterion for freezing of colloidal liquids[Phys. Rev. Lett. 70, 1557 (1993)]. We corroborate these predictions by comparing molecular and Brownian dynamics simulations on (soft- and hard-sphere) model systems, representative of what we may refer to as the "hard-sphere" dynamic universality class.
Dynamical modelling of the Milky Way Bar/Bulge
Creators: name: Shen, Juntai
Publisher: name: Zenodo
Year: 2019

description: I review the recent progresses on the properties of the Galactic bar and bulge, and the major theoretical models and techniques to understand the Milky Way bulge. Despite these recent advances, a complete bulge formation model that explains the full kinematics and metallicity distribution is still not fully understood. Upcoming large surveys are expected to shed new light on the formation history of the Galactic bar and bulge.
MPEC 2024-C65 : 2024 CY
Creators: name: Minor Planet Center Staff
Publisher: name: The Minor Planet Center
Year: 2024
Subjects: subject: Small Solar System bodies
valueUri: http://astrothesaurus.org/uat/1469
subject: 2024 CY

description: The Minor Planet Electronic Circulars contain information on unusual minor planets, routine data on comets and natural satellites, and occasional editorial announcements.  They are published on behalf of Division F of the International Astronomical Union by the Minor Planet Center, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Unpolarized isovector quark distribution function from lattice QCD: A systematic analysis of renormalization and matching
Creators: name: Liu, Yu-Sheng
name: Chen, Jiunn-Wei
name: Huo, Yi-Kai
name: Jin, Luchang
name: Schlemmer, Maximilian
name: Schäfer, Andreas
name: Sun, Peng
name: Wang, Wei
name: Yang, Yi-Bo
name: Zhang, Jian-Hui
name: Zhang, Qi-An
name: Zhang, Kuan
name: Zhao, Yong
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: We present a detailed lattice QCD study of the unpolarized isovector quark parton distribution function (PDF) using a large-momentum effective theory framework. We choose a quasi-PDF defined by a spatial correlator which is free from mixing with other operators of the same dimension. In the lattice simulation, we use a Gaussian-momentum-smeared source at Mπ=356 MeV and Pz∈{1.8,2.3} GeV. To control the systematics associated with the excited states, we explore five different source-sink separations. The nonperturbative renormalization is conducted in a regularization-independent momentum subtraction scheme, and the matching between the renormalized quasi-PDF and ¯¯¯¯¯¯MS PDF is calculated based on perturbative QCD up to one-loop order. Systematic errors due to renormalization and perturbative matching are also analyzed in detail. Our results for light-cone PDF are in reasonable agreement with the latest phenomenological analysis.
Mass profiles and concentration-dark matter relation in X-ray luminous galaxy clusters
Creators: name: Ettori, S.
name: Gastaldello, F.
name: Leccardi, A.
name: Molendi, S.
name: Rossetti, M.
name: Buote, D.
name: Meneghetti, M.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: (Abriged) Assuming that the hydrostatic equilibrium holds between the intracluster medium and the gravitational potential, we constrain the NFW profiles in a sample of 44 X-ray luminous galaxy clusters observed with XMM-Newton in the redshift range 0.1-0.3. We evaluate several systematic uncertainties that affect our reconstruction of the X-ray masses. We measure the concentration c200, the dark mass M200 and the gas mass fraction within R500 in all the objects of our sample, providing the largest dataset of mass parameters for galaxy clusters in this redshift range. We confirm that a tight correlation between c200 and M200 is present and in good agreement with the predictions from numerical simulations and previous observations. When we consider a subsample of relaxed clusters that host a Low-Entropy-Core (LEC), we measure a flatter c-M relation with a total scatter that is lower by 40 per cent. From the distribution of the estimates of c200 and M200, with associated statistical (15-25%) and systematic (5-15%) errors, we use the predicted values from semi-analytic prescriptions calibrated through N-body numerical runs and measure sigma_8*Omega_m^(0.60+-0.03)= 0.45+-0.01 (at 2 sigma level, statistical only) for the subsample of the clusters where the mass reconstruction has been obtained more robustly, and sigma_8*Omega_m^(0.56+-0.04) = 0.39+-0.02 for the subsample of the 11 more relaxed LEC objects. With the further constraint from the fgas distribution in our sample, we break the degeneracy in the sigma_8-Omega_m plane and obtain the best-fit values sigma_8~1.0+-0.2 (0.75+-0.18 when the subsample of the more relaxed objects is considered) and Omega_m = 0.26+-0.01.
description: 21 pages. A&A in press. Minor revisions to match accepted version. Corrected 2nd and 3rd column in Table 3, and equation (A.4)
Hadronic Light-by-Light Scattering Contribution to the Muon Anomalous Magnetic Moment from Lattice QCD
Creators: name: Blum, Thomas
name: Christ, Norman
name: Hayakawa, Masashi
name: Izubuchi, Taku
name: Jin, Luchang
name: Jung, Chulwoo
name: Lehner, Christoph
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: We report the first result for the hadronic light-by-light scattering contribution to the muon anomalous magnetic moment with all errors systematically controlled. Several ensembles using 2+1 flavors of physical mass Möbius domain-wall fermions, generated by the RBC and UKQCD collaborations, are employed to take the continuum and infinite volume limits of finite volume lattice QED+QCD. We find aHLbLμ=7.87(3.06)stat(1.77)sys×10−10. Our value is consistent with previous model results and leaves little room for this notoriously difficult hadronic contribution to explain the difference between the standard model and the BNL experiment.
FLAG Review 2019
Creators: name: Aoki, S.
name: Aoki, Y.
name: Bečirević, D.
name: Blum, T.
name: Colangelo, G.
name: Collins, S.
name: Della Morte, M.
name: Dimopoulos, P.
name: Dürr, S.
name: Fukaya, H.
name: Golterman, M.
name: Gottlieb, Steven
name: Gupta, R.
name: Hashimoto, S.
name: Heller, U. M.
name: Herdoiza, G.
name: Horsley, R.
name: Jüttner, A.
name: Kaneko, T.
name: Lin, C.-J. D.
name: Lunghi, E.
name: Mawhinney, R.
name: Nicholson, A.
name: Onogi, T.
name: Pena, C.
name: Portelli, A.
name: Ramos, A.
name: Sharpe, S. R.
name: Simone, J. N.
name: Simula, S.
name: Sommer, R.
name: Van de Water, R.
name: Vladikas, A.
name: Wenger, U.
name: Wittig, H.
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: We review lattice results related to pion, kaon, D-meson, B-meson, and nucleon physics with the aim of making them easily accessible to the nuclear and particle physics communities. More specifically, we report on the determination of the light-quark masses, the form factor f+(0) arising in the semileptonic K→π transition at zero momentum transfer, as well as the decay constant ratio fK/fπ and its consequences for the CKM matrix elements Vus and Vud. Furthermore, we describe the results obtained on the lattice for some of the low-energy constants of SU(2)L×SU(2)R and SU(3)L×SU(3)R Chiral Perturbation Theory. We review the determination of the BK parameter of neutral kaon mixing as well as the additional four B parameters that arise in theories of physics beyond the Standard Model. For the heavy-quark sector, we provide results for mc and mb as well as those for D- and B-meson decay constants, form factors, and mixing parameters. These are the heavy-quark quantities most relevant for the determination of CKM matrix elements and the global CKM unitarity-triangle fit. We review the status of lattice determinations of the strong coupling constant αs. Finally, in this review we have added a new section reviewing results for nucleon matrix elements of the axial, scalar and tensor bilinears, both isovector and flavor diagonal.
Dark Matter And The Habitability of Planets
Creators: name: Hooper, Dan
name: Steffen, Jason H.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In many models, dark matter particles can elastically scatter with nuclei in planets, causing those particles to become gravitationally bound. While the energy expected to be released through the subsequent annihilations of dark matter particles in the interior of the Earth is negligibly small (a few megawatts in the most optimistic models), larger planets that reside in regions with higher densities of slow moving dark matter could plausibly capture and annihilate dark matter at a rate high enough to maintain liquid water on their surfaces, even in the absence of additional energy from starlight or other sources. On these rare planets, it may be dark matter rather than light from a host star that makes it possible for life to emerge, evolve, and survive.
description: 9 pages, 3 figures, updated calculations with a larger velocity dispersion for the central portion of the Milky Way
Transverse Momentum Dependent Observables from Low to High Energy: Factorization, Evolution, and Global Analyses
Creators: name: Pitonyak, Daniel
name: Kang, Zhong-Bo
name: Prokudin, Alexei
name: Vladimirov, Alexey
Publisher: name: Universität Regensburg
Year: 2019
Subjects: subject: 530 Physik

description: Transverse momentum dependent (TMD) observables in high-energy particle collisions allow one to study the motion of hadron constituents (partons) in three dimensions. The intense theoretical, phenomenological, and experimental work over the last several decades has seen great progress in modeling and extracting TMD parton distribution functions (PDFs) and fragmentation functions (FFs) [1, 2]. The wealth of experimental data, both current and future [3–6], across various reactions and energy ranges, along with substantial progress in other approaches, such as Lattice QCD [7], has increased the demand to rigorously study the intrinsic transverse motion of hadrons. Such issues currently being addressed include factorization, evolution, and operator definitions of TMD distributions, as well as how they influence phenomenological and Lattice QCD studies. Therefore, in this special issue we attempt to further the effort of understanding TMD structure through a series of review articles that address some of the significant areas of ongoing research.
Building sets of reference stars for current and future spectroscopic survey stellar parameters
Creators: name: Tucci Maia, Marcelo
Publisher: name: Zenodo
Year: 2019

description: One of the main deliveries of spectroscopic surveys are the stellar parameters and abundances that are determined from automatic pipelines. In this talk I will present 2 important sets of stars that have been used to validate and calibrate the astrophysical parameters of not only several spectroscopic surveys but also Gaia DR2 parameters from the BP/RP spectra. These are the Gaia benchmark stars and a sample of solar twins, both developed by our group at the Astronomy Nucleus in Chile. I will discuss our current activities and future plans for the next generation of spectroscopic surveys and further data releases of Gaia.
ToxiCraft: A Novel Framework for Synthetic Generation of Harmful Information
Creators: name: Hui, Zheng
name: Guo, Zhaoxiao
name: Zhao, Hang
name: Duan, Juanyong
name: Huang, Congrui
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computation and Language (cs.CL)
subject: Artificial Intelligence (cs.AI)
subject: FOS: Computer and information sciences

description: In different NLP tasks, detecting harmful content is crucial for online environments, especially with the growing influence of social media. However, previous research has two main issues: 1) a lack of data in low-resource settings, and 2) inconsistent definitions and criteria for judging harmful content, requiring classification models to be robust to spurious features and diverse. We propose Toxicraft, a novel framework for synthesizing datasets of harmful information to address these weaknesses. With only a small amount of seed data, our framework can generate a wide variety of synthetic, yet remarkably realistic, examples of toxic information. Experimentation across various datasets showcases a notable enhancement in detection model robustness and adaptability, surpassing or close to the gold labels.
description: EMNLP 2024
A numerical study of the effects of the parameterization of the gaussian process
Creators: name: Foster, Jodie Lynn
Publisher: name: University of British Columbia
Year: 2017

description: Mathematical models implemented as computer code are gaining widespread use across the sciences and engineering. In some cases these model are even replacing physical experiments. The computational complexity of the models typically limits the number of runs that can be performed. In such cases, the Gaussian process is used to emulate the true computer model so that experiments are performed on the emulator. The applicability of the emulator is closely related to the quality of the fitted Gaussian process model. A key step in fitting the Gaussian process is estimating the unknown correlation parameters using a numerical optimizer. It is well known that maximum likelihood estimation is invariant to the parameterization of the model. When the mapping from one parametrization to another is injective this leads to an equivalence of the likelihood and in a Bayesian context an equivalence of the posterior for carefully chosen prior distributions. In the context of a Gaussian process model, we show that the parameterization of the model is in fact critical to achieving meaningful results and ensuring convergence of the optimizer. This thesis is aimed at providing practical advice on the best parameterization for the Gaussian process model. The approach presented here implements a simulation study on a wide range of test problems and a large number of parameterizations. We illustrate that the parameterization can have a huge effect on the fitted model and show that many of the commonly used parameterizations are in fact sub-optimal for fitting the Gaussian process.
Non-perturbative structure of semi-inclusive deep-inelastic and Drell-Yan scattering at small transverse momentum
Creators: name: Scimemi, Ignazio
name: Vladimirov, Alexey
Publisher: name: Universität Regensburg
Year: 2020
Subjects: subject: 530 Physik

description: We consider semi-inclusive deep inelastic scattering (SIDIS) and Drell-Yan events within transverse momentum dependent (TMD) factorization. Based on the simultaneous fit of multiple data points, we extract the unpolarized TMD distributions and the non-perturbative evolution kernel. The high quality of the fit confirms a complete universality of TMD non-perturbative distributions. The extraction is supplemented by phenomenological analyses of various parts of the TMD factorization, such as sensitivity to non-perturbative parameterizations, perturbative orders, collinear distributions, correlations between parameters, and others.
Black Hole Instability Induced by a Magnetic Field
Creators: name: Ammon, Martin
name: Erdmenger, Johanna
name: Kerner, Patrick
name: Strydom, Migael
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In the context of gauge/gravity duality, we find a new black hole instability in asymptotically AdS spaces. On the field theory side, this instability is induced by a magnetic field in the vacuum, in contrast to previous instabilities which occur at finite density. On the gravity side, this corresponds to a spatial component of the gauge field in SU(2) Einstein-Yang-Mills theory, which provides the crucial non-Abelian structure. Our analysis may provide supporting evidence for recent QCD studies of Rho-meson condensation induced by a magnetic field.
description: 13 pages, 2 figures v2: Added references, fixed typos
A local-global principle for rational isogenies of prime degree
Creators: name: Sutherland, Andrew V.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Number Theory (math.NT)
subject: FOS: Mathematics
subject: 11G05

description: Let K be a number field. We consider a local-global principle for elliptic curves E/K that admit (or do not admit) a rational isogeny of prime degree n. For suitable K (including K=Q), we prove that this principle holds when n = 1 mod 4, and for n < 7, but find a counterexample when n = 7 for an elliptic curve with j-invariant 2268945/128. For K = Q we show that, up to isomorphism, this is the only counterexample.
description: 11 pages, minor edits, to appear in Journal de Th\'eorie des Nombres de Bordeaux