cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
On the evolution of a star cluster and its multiple stellar systems following gas dispersal
Creators: name: Moeckel, Nickolas
name: Bate, Matthew R.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We investigate the evolution, following gas dispersal, of a star cluster produced from a hydrodynamical calculation. We find that when the gas, initially comprising 60% of the mass, is removed, the system settles into a bound cluster containing 30-40% of the stellar mass surrounding by an expanding halo of ejected stars. The bound cluster expands from an initial radius of <0.05 pc to 1-2 pc over 4-10 Myr, depending on how quickly the gas is removed, implying that stellar clusters may begin with far higher stellar densities than usually assumed. With rapid gas dispersal the most massive stars are found to be mass segregated for the first ~1 Myr of evolution, but classical mass segregation only develops for cases with long gas removal timescales. Eventually, many of the most massive stars are expelled from the bound cluster. Despite the high initial stellar density and the extensive dynamical evolution of the system, we find that the stellar multiplicity is almost constant during the 10 Myr of evolution. This is because the primordial multiple systems are formed in a clustered environment and, thus, by their nature are already resistant to further evolution. The majority of multiple system evolution is confined to the decay of high-order systems and the formation of a significant population of very wide (10^4-10^5 AU) multiple systems in the expanding halo. This formation mechanism for wide binaries potentially solves the problem of how most stars apparently form in clusters and yet a substantial population of wide binaries exist in the field. Many of these wide binaries and the binaries produced by the decay of high-order multiple systems have unequal mass components, potentially solving the problem that hydrodynamical simulations of star formation are found to under-produce unequal-mass solar-type binaries.
description: Accepted by MNRAS, 18 pages, 13 figures
Author items in Wikidata
Creators: name: Cobb, Simon
Publisher: name: Zenodo
Year: 2020
Subjects: Wikidata
WikiCite

description: Analysis of the data quality of author items in Wikidata and discussion of data imports from the ORCID registry. Presented at the WikiCite 2020 Virtual Conference. A recording of the presentation is available on Wikimedia Commons and YouTube.
Effects of Dark Matter Annihilation on the Cosmic Microwave Background
Creators: name: Kanzaki, Toru
name: Kawasaki, Masahiro
name: Nakayama, Kazunori
Publisher: name: arXiv
Year: 2009
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We study the effects of dark matter annihilation during and after the cosmic recombination epoch on the cosmic microwave background anisotropy, taking into account the detailed energy deposition of the annihilation products. It is found that a fairly stringent constraint on the annihilation cross section is imposed for TeV scale dark matter masses from WMAP observations.
description: 14 pages, 5 figures
Canadian Postwar Book Diplomacy and Settler Contradiction
Creators: name: Mason, Jody
Publisher: name: Canadian Literature
Year: 2020

description: A standard narrative in the literary history of English Canada is that literary culture was able to “develop” in the wake of the 1951 Massey Report, finally “arriving” in the years between the late 1950s and the mid-1970s. This essay offers another view of this period, analyzing not the smooth developmental momentum but rather the contradiction and disavowal that attended one of the federal government’s first direct forms of support for the book, which came in the form of postwar book diplomacy efforts. Using Anna Johnston and Allan Lawson's theorization of settler colonialism, the essay analyzes how these book diplomacy undertakings exemplify the "double inscription of authority and authenticity" of settler contradiction. As the Imperium shifted across the Atlantic in the decade that followed the close of the Second World War, the settler nation struggled to locate itself anew in relation to its doubled, desired, and disavowed origins.
description: Canadian Literature, No. 240 (2020): Decolonial (Re)Visions of Science Fiction, Fantasy, and Horror
Statics and Dynamics of Colloid-Polymer Mixtures Near Their Critical Point of Phase Separation: A Computer Simulation Study of a Continuous AO Model
Creators: name: Zausch, Jochen
name: Virnau, Peter
name: Binder, Kurt
name: Horbach, Juergen
name: Vink, Richard L.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: FOS: Physical sciences

description: We propose a new coarse-grained model for the description of liquid-vapor phase separation of colloid-polymer mixtures. The hard-sphere repulsion between colloids and between colloids and polymers, which is used in the well-known Asakura-Oosawa (AO) model, is replaced by Weeks-Chandler-Anderson potentials. Similarly, a soft potential of height comparable to thermal energy is used for the polymer-polymer interaction, rather than treating polymers as ideal gas particles. It is shown by grand-canonical Monte Carlo simulations that this model leads to a coexistence curve that almost coincides with that of the AO model and the Ising critical behavior of static quantities is reproduced. Then the main advantage of the model is exploited - its suitability for Molecular Dynamics simulations - to study the dynamics of mean square displacements of the particles, transport coefficients such as the self-diffusion and interdiffusion coefficients, and dynamic structure factors. While the self-diffusion of polymers increases slightly when the critical point is approached, the self-diffusion of colloids decreases and at criticality the colloid self-diffusion coefficient is about a factor of 10 smaller than that of the polymers. Critical slowing down of interdiffusion is observed, which is qualitatively similar to symmetric binary Lennard-Jones mixtures, for which no dynamic asymmetry of self-diffusion coefficients occurs.
description: 42 pages, 17 figures, submitted to J. Chem. Phys
Angle-Resolved Magneto-Chiral Anisotropy in a Non-Centrosymmetric Atomic Layer Superlattice
Creators: name: Cheng, Long
name: Bao, Mingrui
name: Zhang, Jingxian
name: Zhang, Xue
name: Yang, Qun
name: Li, Qiang
name: Cao, Hui
name: Qiu, Dawei
name: Liu, Jia
name: Ye, Fei
name: Wang, Qing
name: Liang, Genhao
name: Li, Hui
name: Cheng, Guanglei
name: Zhou, Hua
name: Zuo, Jian-Min
name: Zhou, Xiaodong
name: Shen, Jian
name: Zhu, Zhifeng
name: Mu, Sai
name: Wang, Wenbo
name: Zhai, Xiaofang
Publisher: name: arXiv
Year: 2024
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: Chirality in solid-state materials has sparked significant interest due to potential applications of topologically-protected chiral states in next-generation information technology. The electrical magneto-chiral effect (eMChE), arising from relativistic spin-orbit interactions, shows great promise for developing chiral materials and devices for electronic integration. Here we demonstrate an angle-resolved eMChE in an A-B-C-C type atomic-layer superlattice lacking time and space inversion symmetry. We observe non-superimposable enantiomers of left-handed and right-handed tilted uniaxial magnetic anisotropy as the sample rotates under static fields, with the tilting angle reaching a striking 45 degree. Magnetic force microscopy and atomistic simulations correlate the tilt to the emergence and evolution of chiral spin textures. The Dzyaloshinskii-Moriya interaction lock effect in competition with Zeeman effect is demonstrated to be responsible for the angle-resolved eMChE. Our findings open up a new horizon for engineering angle-resolved magneto-chiral anisotropy, shedding light on the development of novel angle-resolved sensing or writing techniques in chiral spintronics.
Multistability of globally coupled Duffing oscillators
Creators: name: Sosa, Raúl I.
name: Zanette, Damián H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Adaptation and Self-Organizing Systems (nlin.AO)
subject: Classical Physics (physics.class-ph)
subject: FOS: Physical sciences

description: We analyze the collective dynamics of an ensemble of globally coupled, externally forced, identical mechanical oscillators with cubic nonlinearity. Focus is put on solutions where the ensemble splits into two internally synchronized clusters, as a consequence of the bistability of individual oscillators. The multiplicity of these solutions, induced by the many possible ways of distributing the oscillators between the two clusters, implies that the ensemble can exhibit multistability. As the strength of coupling grows, however, the two-cluster solutions are replaced by a state of full synchronization. By a combination of analytical and numerical techniques, we study the existence and stability of two-cluster solutions. The role of the distribution of oscillators between the clusters and the relative prevalence of the two stable solutions are disclosed.
'In this very uncertain space'
Creators: name: Troeung, Y-Dang
name: Antwi, Phanuel
Publisher: name: Canadian Literature
Year: 2020

description: As a journalist for The Globe and Mail for 10 years, El Akkad has reported on war and conflict from around the world, including the war in Afghanistan, the military trials at Guantanamo Bay, the Arab Spring revolution in Egypt, and the Black Lives Matter movement in Ferguson, Missouri. In 2018, El Akkad's debut novel, American War, was shortlisted for a number of prominent literary prizes, garnering public attention as a finalist on the CBC Canada Reads competition. In this conversation, we talk to El Akkad about his novel, journalism, literary influences, migrations, and political visions of the future. One recurring theme in the conversation is the relationship between violence and the production of uncertainty—the unpredictability movement and refuge for the displaced; the ambiguity and risks of racial representation; the secrecy of detention and redaction; and the uncertainties of the future in times of change and crisis.
description: Canadian Literature, No. 240 (2020): Decolonial (Re)Visions of Science Fiction, Fantasy, and Horror
MeSH Term Suggestion for Systematic Review Literature Search
Creators: name: Wang, Shuai
name: Li, Hang
name: Scells, Harrisen
name: Locke, Daniel
name: Zuccon, Guido
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: High-quality medical systematic reviews require comprehensive literature searches to ensure the recommendations and outcomes are sufficiently reliable. Indeed, searching for relevant medical literature is a key phase in constructing systematic reviews and often involves domain (medical researchers) and search (information specialists) experts in developing the search queries. Queries in this context are highly complex, based on Boolean logic, include free-text terms and index terms from standardised terminologies (e.g., MeSH), and are difficult and time-consuming to build. The use of MeSH terms, in particular, has been shown to improve the quality of the search results. However, identifying the correct MeSH terms to include in a query is difficult: information experts are often unfamiliar with the MeSH database and unsure about the appropriateness of MeSH terms for a query. Naturally, the full value of the MeSH terminology is often not fully exploited. This paper investigates methods to suggest MeSH terms based on an initial Boolean query that includes only free-text terms. These methods promise to automatically identify highly effective MeSH terms for inclusion in a systematic review query. Our study contributes an empirical evaluation of several MeSH term suggestion methods. We perform an extensive analysis of the retrieval, ranking, and refinement of MeSH term suggestions for each method and how these suggestions impact the effectiveness of Boolean queries.
description: To be published in Australasian Document Computing Symposium 2021, Melbourne, Australia
Derived functors and Hilbert polynomials over hypersurface rings
Creators: name: Puthenpurakal, Tony J.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Commutative Algebra (math.AC)
subject: FOS: Mathematics
subject: Primary 13D09, 13A30, Secondary 13H10

description: Let $(A,\mathfrak{m})$ be a hypersurface local ring of dimension $d \geq 1$ and let $I$ be an $\mathfrak{m}$-primary ideal. We show that there is a non-negative integer $r_I$ (depending only on $I$) such that if $M$ is any non-free maximal Cohen-Macaulay $A$-module the function $n \rightarrow \ell(Tor^A_1(M, A/I^{n+1}))$ (which is of polynomial type) has degree $r_I$. Analogous results hold for Hilbert polynomials associated to Ext-functors. Surprisingly a key ingredient is the classification of thick subcategories of the stable category of MCM $A$-modules (obtained by Takahashi).
description: Two new results added. Some typos corrected
Membership Practices of Local Cooperatives
Creators: name: LeBeau, Oscar R.
name: LeBeau, Oscar R.
Publisher: name: Unknown
Year: 1960
Subjects: Agribusiness
Community/Rural/Urban Development
Teaching/Communication/Extension/Profession

description: Excerpts from the report: To obtain a general picture of the membership practices of local cooperatives, Farmer Cooperative Service mailed a special questionnaire recently to 511 cooperative managers throughout the United States. Details of how the sample was drawn are summarized in the appendix, page 24. Cooperative managers and directors interested in maintaining favorable relations with their members frequently ask about the membership practices of other associations. This report is designed to answer many of those questions as well as to create interest in solving many of the member relations problems confronting farmer cooperatives.
On the use of a single site approximation to describe correlation in pure metals
Creators: name: Chaves, C. M.
name: Gomes, A. A.
name: Troper, A.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: The magnetic properties of pure transition-like metals are discussed within the single site approximation, to take into account the electron correlation. The metal is described by two hybridized bands one of which includes the Coulomb correlation. Our results indicate that ferromagnetism follows from adequate values of the correlation and hybridization.
description: 2 pages and 2 figures
Automatisierte Erkennung von Fehlern bei der Wartung von IT-Services
Creators: name: Vetter, Arthur
Publisher: name: KIT Scientific Publishing
Year: 2019
Subjects: TOSCA
IT-Service-Wartung
Petri-Netze
Anti-Pattern
Fehlererkennung
Anomaly Detection
Petri Nets
Operator Errors

description: Wartungsfehler sind einer der häufigsten Gründe für IT-Service-Ausfälle und können bei IT-Service-Anbietern Schäden in Millionenhöhe verursachen. In diesem Buch wird eine Methode vorgestellt, die es IT-Service-Anbietern ermöglicht, Wartungsfehler automatisiert während der Durchführung einer IT-Service-Wartung zu erkennen. Dadurch können Wartungsfehler behoben werden, bevor sie Schaden anrichten können.
Familiarizing Grist Village
Creators: name: Lai, Larissa
Publisher: name: Canadian Literature
Year: 2020

description: Larissa Lai explains that she writes speculative fiction in order to embrace her own writerly agency. She takes up the practice of the thought experiment, first envisioned by Ursula LeGuin, as a way of narratively testing out ideas that could be practiced in the world as it is. Lai adds to this by recognizing that the world changes in multiple ways at once, and that we get new worlds and fresh futures not through a single change but through the concatenation of many, often driven by differing ideals. We can’t predict the results of ideals interacting, but we can learn to recognize beautiful, freeing or interesting things when they emerge. The marvel of speculative fiction is that it can show us how this might work, as for example in The Tiger Flu, Lai's novel about a community of self-reproducing women and a disease that favours men.
description: Canadian Literature, No. 240 (2020): Decolonial (Re)Visions of Science Fiction, Fantasy, and Horror
SDSS-IV MaStar: Data-driven Parameter Derivation for the MaStar Stellar Library
Creators: name: Imig, Julie
name: Holtzman, Jon A.
name: Yan, Renbin
name: Lazarz, Daniel
name: Chen, Yanping
name: Hill, Lewis
name: Thomas, Daniel
name: Maraston, Claudia
name: Prescott, Moire M. K.
name: Stringfellow, Guy S.
name: Bizyaev, Dmitry
name: Beaton, Rachael L.
name: Drory, Niv
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: The MaNGA Stellar Library (MaStar) is a large collection of high-quality empirical stellar spectra designed to cover all spectral types and ideal for use in the stellar population analysis of galaxies observed in the Mapping Nearby Galaxies at Apache Point Observatory (MaNGA) survey. The library contains 59,266 spectra of 24,130 unique stars with spectral resolution $R\sim1800$ and covering a wavelength range of $3,622-10,354$ Å. In this work, we derive five physical parameters for each spectrum in the library: effective temperature ($T_{eff}$), surface gravity ($\log g$), metalicity ($[Fe/H]$), micro-turbulent velocity ($\log(v_{micro})$), and alpha-element abundance ($[α/Fe]$). These parameters are derived with a flexible data-driven algorithm that uses a neural network model. We train a neural network using the subset of 1,675 MaStar targets that have also been observed in the Apache Point Observatory Galactic Evolution Experiment (APOGEE), adopting the independently-derived APOGEE Stellar Parameter and Chemical Abundance Pipeline (ASPCAP) parameters for this reference set. For the regions of parameter space not well represented by the APOGEE training set ($7,000 \leq T \leq 30,000$ K), we supplement with theoretical model spectra. We present our derived parameters along with an analysis of the uncertainties and comparisons to other analyses from the literature.
description: 16 figures, 3 tables, accepted to AJ
Observation of shock waves in a large Bose-Einstein condensate
Creators: name: Meppelink, R.
name: Koller, S. B.
name: Vogels, J. M.
name: van der Straten, P.
name: van Ooijen, E. D.
name: Heckenberg, N. R.
name: Rubinsztein-Dunlop, H.
name: Haine, S. A.
name: Davis, M. J.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Quantum Gases (cond-mat.quant-gas)
subject: FOS: Physical sciences

description: We observe the formation of shock waves in a Bose-Einstein condensate containing a large number of sodium atoms. The shock wave is initiated with a repulsive, blue-detuned light barrier, intersecting the BEC, after which two shock fronts appear. We observe breaking of these waves when the size of these waves approaches the healing length of the condensate. At this time, the wave front splits into two parts and clear fringes appear. The experiment is modeled using an effective 1D Gross-Pitaevskii-like equation and gives excellent quantitative agreement with the experiment, even though matter waves with wavelengths two orders of magnitude smaller than the healing length are present. In these experiments, no significant heating or particle loss is observed.
description: 7 pages, 7 figures
Varying couplings in the early universe: correlated variations of $α$ and $G$
Creators: name: Martins, C. J. A. P.
name: Menegoni, Eloisa
name: Galli, Silvia
name: Mangano, Gianpiero
name: Melchiorri, Alessandro
Publisher: name: arXiv
Year: 2010
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The Cosmic Microwave Background anisotropies provide a unique opportunity to constrain simultaneous variations of the fine-structure constant $α$ and Newton's gravitational constant $G$. Those correlated variations are possible in a wide class of theoretical models. In this brief paper we show that the current data, assuming that particle masses are constant, gives no clear indication for such variations, but already prefers that any relative variations in $α$ should be of the same sign of those of $G$ for variations of $\sim 1 %$. We also show that a cosmic complementarity is present with Big Bang Nucleosynthesis and that a combination of current CMB and BBN data strongly constraints simultaneous variations in $α$ and $G$. We finally discuss the future bounds achievable by the Planck satellite mission.
description: 6 pages, 5 figures; one author added, now includes discussion of BBN constraints
A spectroscopic follow-up for Gaia19bld
Creators: name: Bachelet, E.
name: Zielinski, P.
name: Gromadzki, M.
name: Gezer, I.
name: Rybicki, K.
name: Kruszynska, K.
name: Ihanec, N.
name: Wyrzykowski, L.
name: Street, R. A.
name: Tsapras, Y.
name: Hundertmark, M.
name: Cassan, A.
name: Harbeck, D.
name: Rabus, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Due to their scarcity, microlensing events in the Galactic disk are of great interest and high-cadence photometric observations, supplemented by spectroscopic follow-up, are necessary for constraining the physical parameters of the lensing system. In particular, a precise estimate of the source characteristics is required to accurately measure the lens distance and mass. We conducted a spectroscopic follow-up of microlensing event Gaia19bld to derive the properties of the microlensing source and, ultimately, to estimate the mass and distance of the lens. We obtained low- and high-resolution spectroscopy from multiple sites around the world during the course of the event. The spectral lines and template matching analysis has led to two independent, consistent characterizations of the source. We found that the source is a red giant located at about 8.5 kpc from the Earth. Combining our results with the photometric analysis has led to a lens mass of Ml=1.1 M at a distance of D l = 5.5 kpc. We did not find any significant blend light in the spectra (with an upper detection limit of V < 17 mag), which is in agreement with photometric observations. Therefore, we cannot exclude the possibility that the lens is a main-sequence star. Indeed, we predict in this scenario a lens brightness of V about 20 mag, a value that would make it much fainter than the detection limit.
description: A&A in press
Universal Thermal Entanglement of Multichannel Kondo Effects
Creators: name: Kim, Donghoon
name: Shim, Jeongmin
name: Sim, H. -S.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Quantum entanglement between an impurity and its environment is expected to be central in quantum impurity problems. We develop a method to compute the entanglement in spin-1/2 impurity problems, based on the entanglement negativity and the boundary conformal field theory (BCFT). Using the method, we study the thermal decay of the entanglement in the multichannel Kondo effects. At zero temperature, the entanglement has the maximal value independent of the number of the screening channels. At low temperature, the entanglement exhibits a power-law thermal decay. The power-law exponent equals two times of the scaling dimension of the BCFT boundary operator describing the impurity spin, and it is attributed to the energy-dependent scaling behavior of the entanglement in energy eigenstates. These agree with numerical renormalization group results, unveiling quantum coherence inside the Kondo screening length.
Understanding the Cluster LP for Correlation Clustering
Creators: name: Cao, Nairen
name: Cohen-Addad, Vincent
name: Lee, Euiwoong
name: Li, Shi
name: Newman, Alantha
name: Vogl, Lukas
Publisher: name: arXiv
Year: 2024
Subjects: subject: Data Structures and Algorithms (cs.DS)
subject: FOS: Computer and information sciences

description: In the classic Correlation Clustering problem introduced by Bansal, Blum, and Chawla~(FOCS 2002), the input is a complete graph where edges are labeled either $+$ or $-$, and the goal is to find a partition of the vertices that minimizes the sum of the +edges across parts plus the sum of the -edges within parts. In recent years, Chawla, Makarychev, Schramm and Yaroslavtsev~(STOC 2015) gave a 2.06-approximation by providing a near-optimal rounding of the standard LP, and Cohen-Addad, Lee, Li, and Newman~(FOCS 2022, 2023) finally bypassed the integrality gap of 2 for this LP giving a $1.73$-approximation for the problem.
 In order to create a simple and unified framework for Correlation Clustering similar to those for {\em typical} approximate optimization tasks, we propose the {\em cluster LP} as a strong linear program that might tightly capture the approximability of Correlation Clustering. It unifies all the previous relaxations for the problem.
 We demonstrate the power of the cluster LP by presenting a simple rounding algorithm, and providing two analyses, one analytically proving a 1.49-approximation and the other solving a factor-revealing SDP to show a 1.437-approximation. Both proofs introduce principled methods by which to analyze the performance of the algorithm, resulting in a significantly improved approximation guarantee.
 Finally, we prove an integrality gap of $4/3$ for the cluster LP, showing our 1.437-upper bound cannot be drastically improved. Our gap instance directly inspires an improved NP-hardness of approximation with a ratio $24/23 \approx 1.042$; no explicit hardness ratio was known before.
Ab initio calculation of intrinsic spin Hall conductivity of Pd and Au
Creators: name: Guo, G. Y.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: An {\it ab initio} relativistic band structure calculation of spin Hall conductivity (SHC) ($σ_{xy}^z$) in Pd and Au metals has been performed. It is found that at low temperatures, intrinsic SHCs for Pd and Au are, respectively, $\sim 1400 (\hbar/e)(Ω{\rm cm})^{-1}$ and $\sim 400 (\hbar/e)(Ω{\rm cm})^{-1}$. The large SHC in Pd comes from the resonant contribution from the spin-orbit splitting of the doubly degenerated 4$d$ bands near the Fermi level at symmetry $Γ$ and X points, and the smaller SHC in Au is due to the broad free electron like 6$s6p$-bands. However, as the temperature increases, the SHC in Pd decreases monotonically and reduces to $\sim 330 (\hbar/e)(Ω{\rm cm})^{-1}$ at 300 K, while the SHC in Au increases steadily and reaches $\sim 750 (\hbar/e)(Ω{\rm cm})^{-1}$ at room temperature. This indicates that the gigantic spin Hall effect [$σ_{xy}^z \approx 10^5 (\hbar/e)(Ω{\rm cm})^{-1}$] observed recently in the Au/FePt system [T. Seki, {\it et al.}, Nature Materials {\bf 7}, 125 (2008)] is due to the extrinsic mechanisms such as the skew scattering by the impurities in Au.
description: Accepted for publication in J. Appl. Phys
Collective coordinate variable for soliton-potential system in sine-Gordon model
Creators: name: Javidan, Kurosh
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: A Collective coordinate variable for adding a space dependent potential to the sine-Gordon model is presented. Interaction of solitons with a delta function potential barrier and also delta function potential well is investigated. Most of the characters of interaction are derived analytically. We will find that the behaviour of a solitonic solution is like a point particle which is moved under the influence of a complicated effective potential. The effective potential is a function of the field initial conditions and also parameters of added potential.
description: 10 pages, 6 figures
Nonequilibrium system-bath entanglement theorem versus heat transport
Creators: name: Du, Peng-Li
name: Chen, Zi-Hao
name: Su, Yu
name: Wang, Yao
name: Xu, Rui-Xue
name: Yan, YiJing
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: In this work, we extend the recently established system-bath entanglement theorem (SBET) [J. Chem. Phys. 152, 034102 (2020)] to the nonequilibrium scenario, in which an arbitrary system couples to multiple Gaussian baths environments at different temperatures. While the existing SBET connects the entangled system-bath response functions to those of local systems, the extended theory is concerned with the nonequilibrium steady-state quantum transport current through molecular junctions. The new theory is established on the basis of the generalized Langevin equation, with a close relation to nonequilibrium thermodynamics in the quantum regime.
description: 4 pages,1 table
Frequency converter based on nanoscale MgO magnetic tunnel junctions
Creators: name: Georges, B.
name: Grollier, J.
name: Cros, V.
name: Marcilhac, B.
name: Crété, D. -G.
name: Mage, J. -C.
name: Fert, A.
name: Fukushima, A.
name: Kubota, H.
name: Yakushijin, K.
name: Yuasa, S.
name: Ando, K.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We observe both dc voltage rectification and frequency conversion that occur when a reference microwave current is injected to a MgO based magnetic tunnel junction (MTJ). The rectification that is spin-transfer torque dependent is observed when the frequency of the input microwave current coincides with the resonance frequency of the magnetization of the active layer. In addition, we demonstrate that frequency conversion is the result of amplitude modulation between the reference signal and the resistance of the MTJ that is fluctuating at the resonance frequency of the magnetization of the active layer.
description: 9 pages, 2 figures
Bilgi ve Belge Yönetimi Öğrencilerinin Evliliğe Bakışı
Creators: name: Yüksek, Dilara
name: Çelikkol, Utku Kaan
name: Özdemir, Dilara
name: Gülbin Çiçek
name: Bolat, Ebru
Publisher: name: Zenodo
Year: 2019
Subjects: Information Management
Marriage

description: Bilgi ve Belge Yönetimi Öğrencilerinin Evliliğe bakışı üzerine yaptığımız anket çalışmasının sonucu baz alınarak hazırlanan poster.
Adversarial Consistency and the Uniqueness of the Adversarial Bayes Classifier
Creators: name: Frank, Natalie S.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Machine Learning (cs.LG)
subject: Statistics Theory (math.ST)
subject: Machine Learning (stat.ML)
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Minimizing an adversarial surrogate risk is a common technique for learning robust classifiers. Prior work showed that convex surrogate losses are not statistically consistent in the adversarial context -- or in other words, a minimizing sequence of the adversarial surrogate risk will not necessarily minimize the adversarial classification error. We connect the consistency of adversarial surrogate losses to properties of minimizers to the adversarial classification risk, known as adversarial Bayes classifiers. Specifically, under reasonable distributional assumptions, a convex surrogate loss is statistically consistent for adversarial learning iff the adversarial Bayes classifier satisfies a certain notion of uniqueness.
description: 2 figures, 20 pages, v2: fixed typos, v3: improved organization of paper and added figures
Searching for a link between the presence of chemical spots on the surface of HgMn stars and their weak magnetic fields
Creators: name: Savanov, I. S.
name: Hubrig, S.
name: Gonzalez, J. F.
name: Schoeller, M.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present the results of mapping the HgMn star AR Aur using the Doppler Imaging technique for several elements and discuss the obtained distributions in the framework of a magnetic field topology.
description: 2 pages, 1 figure, to appear in Proceedings of IAU Symposium 259 "Cosmic Magnetic Fields: from Planets, to Stars and Galaxies", Tenerife, Spain, November 3-7, 2008
Kepler Observations of Transiting Hot Compact Objects
Creators: name: Rowe, Jason F.
name: Borucki, William J.
name: Koch, David
name: Howell, Steve B.
name: Basri, Gibor
name: Batalha, Natalie
name: Brown, Timothy M.
name: Caldwell, Douglas
name: Cochran, William D.
name: Dunham, Edward
name: Dupree, Andrea K.
name: Fortney, Jonathan J.
name: Gautier, Thomas N.
name: Gilliland, Ronald L.
name: Jenkins, Jon
name: Latham, David W.
name: Lissauer, Jack . J.
name: Marcy, Geoff
name: Monet, David G.
name: Sasselov, Dimitar
name: Welsh, William F.
Publisher: name: arXiv
Year: 2010
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Kepler photometry has revealed two unusual transiting companions orbiting an early A-star and a late B-star. In both cases the occultation of the companion is deeper than the transit. The occultation and transit with follow-up optical spectroscopy reveal a 9400 K early A-star, KOI-74 (KIC 6889235), with a companion in a 5.2 day orbit with a radius of 0.08 Rsun and a 10000 K late B-star KOI-81 (KIC 8823868) that has a companion in a 24 day orbit with a radius of 0.2 Rsun. We infer a temperature of 12250 K for KOI-74b and 13500 K for KOI-81b. We present 43 days of high duty cycle, 30 minute cadence photometry, with models demonstrating the intriguing properties of these object, and speculate on their nature.
description: 12 pages, 3 figures, submitted to ApJL (updated to correct KOI74 lightcurve)
Effects of the higher partial waves and relativistic terms on the accuracy of the calculation of the hypertriton electroproduction
Creators: name: Mart, T.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We have investigated the accuracies of calculations made by omitting the higher partial waves of nuclear wave functions and the elementary relativistic terms in the hypertriton electroproduction. We found that an accurate calculation would still be obtained if we used at least three lowest partial waves with isospin T = 0. Furthermore, we found that the omission of the relativistic terms in the elementary process amplitude could lead to a large deviation from the full calculation. We also present the cpu-times required to calculate the cross sections. For future consideration the use of these lowest partial waves is suggested, since the calculated cross section deviates only about 0.17 nb/sr (approximately 4%), at most, from the full calculation, whereas the cpu-time is reduced by a factor of 60. Comparison of our result with the available experimental data supports these findings.
description: 12 pages, 4 figures, submitted to Nucl. Phys. A
Chemo-dynamics and asteroseismic ages of seven metal-poor red giants from the Kepler field
Creators: name: Puls, Arthur Alencastro
name: Casagrande, Luca
name: Monty, Stephanie
name: Yong, David
name: Liu, Fan
name: Stello, Dennis
name: Børsen-Koch, Victor Aguirre
name: Freeman, Ken C.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: In this work we combine information from solar-like oscillations, high-resolution spectroscopy and Gaia astrometry to derive stellar ages, chemical abundances and kinematics for a group of seven metal-poor Red Giants and characterise them in a multidimensional chrono-chemo-dynamical space. Chemical abundance ratios were derived through classical spectroscopic analysis employing 1D LTE atmospheres on Keck/HIRES spectra. Stellar ages, masses and radii were calculated with grid-based modelling, taking advantage of availability of asteroseismic information from Kepler. The dynamical properties were determined with Galpy using Gaia EDR3 astrometric solutions. Our results suggest that underestimated parallax errors make the effect of Gaia parallaxes more important than different choices of model grid or -- in the case of stars ascending the RGB -- mass-loss prescription. Two of the stars in this study are identified as potentially evolved halo blue stragglers. Four objects are likely members of the accreted Milky Way halo, and their possible relationship with known accretion events is discussed.
description: 15 pages, 8 figures, accepted for publication in MNRAS
Properties of Stellar Clusters around High-Mass Young Stars
Creators: name: Faustini, Fabiana
name: Molinari, Sergio
name: Testi, Leonardo
name: Brand, Jan
Publisher: name: arXiv
Year: 2009
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: [Abridged] Twenty-six high-luminosity IRAS sources believed to be collection of stars in the early phases of high-mass star formation have been observed in the NIR (J, H, K) to characterize the clustering properties of their young stellar population and gain insight into the initial conditions of star formation in these clusters (Initial Mass Function [IMF], Star Formation History [SFH]), and to deduce mean values for cluster ages. K luminosity functions (KLFs) are compared with simulated ones from a model that generates populations of synthetic clusters starting from assumptions on the IMF, the SFH, and the Pre-MS evolution, and using the average properties of the observed clusters as boundary conditions Twenty-two sources show evidence of clustering from a few up to several tens of objects, and a median cluster radius of 0.7 pc. A considerable number of cluster members present an infrared excess characteristic of young Pre-Main-Sequence objects. We find that the median stellar age ranges between 2.5 10^5 and 5 10^6 years, with evidence of an age spread of the same entity within each cluster. We also find evidence that older clusters tend to be smaller in size, in line with the fact that our clusters are on average larger than those around relatively older Herbig Ae/Be stars. The relationship of the mass of the most massive star in the cluster with both the clusters richness and their total stellar mass suggest that our modeled clusters may not be consistent with them resulting from random sampling of the IMF. Our results are consistent with a star formation which takes place continuously over a period of time which is longer than a typical crossing time.
description: Accepted by A&A
Appendix on climate scenarios from Recent natural variability in global warming weakened phenological mismatch and selection on seasonal timing in great tits (Parus major)
Creators: name: Visser, Marcel E.
name: Lindner, Melanie
name: Gienapp, Phillip
name: Long, Matthew C.
name: Jenouvrier, Stephanie
Publisher: name: The Royal Society
Year: 2021
Subjects: subject: Evolutionary Biology
subject: FOS: Biological sciences
subject: Ecology

description: 1: details on the climate scenarios; 2 & 4: details on prediction of temperatures, laying dates and food peak dates; 3:validation of the climate scenarios
Design strategies for the creation of aperiodic nonchaotic attractors
Creators: name: Nandi, Amitabha
name: Bhowmick, Sourav K.
name: Dana, Syamal K.
name: Ramaswamy, Ram
Publisher: name: arXiv
Year: 2009
Subjects: subject: Chaotic Dynamics (nlin.CD)
subject: FOS: Physical sciences

description: Parametric modulation in nonlinear dynamical systems can give rise to attractors on which the dynamics is aperiodic and nonchaotic, namely with largest Lyapunov exponent being nonpositive. We describe a procedure for creating such attractors by using random modulation or pseudo-random binary sequences with arbitrarily long recurrence times. As a consequence the attractors are geometrically fractal and the motion is aperiodic on experimentally accessible timescales. A practical realization of such attractors is demonstrated in an experiment using electronic circuits.
description: 9 pages. CHAOS, In Press, (2009)
The Chiral Restoration Transition of QCD and Low Mass Dileptons
Creators: name: Rapp, R.
name: Wambach, J.
name: van Hees, H.
Publisher: name: arXiv
Year: 2009
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Experiment (nucl-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Recent developments in the evaluation of vector-meson spectral functions in hot and dense matter are discussed with emphasis on connections to the chiral phase transition in QCD. Model independent approaches including chiral low-density expansions, lattice QCD, chiral and QCD sum rules are put into context with model predictions for in-medium vector-spectral function utilizing effective Lagrangians. Hadronic many-body calculations predict a strong broadening (and little mass shift) of the $ρ$ spectral function which rapidly increases close to the expected phase boundary of hadronic and quark-gluon matter. Pertinent dilepton rates appear to degenerate with perturbative quark-antiquark annihilation in the Quark-Gluon Plasma, suggestive for chiral symmetry restoration. Applications to low-mass dilepton spectra in heavy-ion collisions result in quantitative agreement with recent high-quality data at the CERN-SPS. Thermal radiation from temperatures around $T_c$ consistently reproduces the experimental dilepton excess observed at masses above 1 GeV as well. The interpretation of dilepton sources at high transverse momentum appears to be more involved.
description: 48 pages, 59 ps/eps figures
Floral initiation in Bromus species and the effect of planting time on seed production of Bromus inermis climatypes at Beaverlodge, Alberta
Creators: name: Clarke, John Mills
Publisher: name: University of British Columbia
Year: 2011

description: The times of floral initiation of Bromus inermis varieties Carlton (northern-type) and Redpatch (southern-type) and B. pumpellianus from three latitudes were determined under field conditions at Beaverlodge, Alberta. This was done by recording developmental stage of apical meristems of tillers during the spring and fall. A dates of seeding trial involving Carlton and Redpatch was also undertaken. It was found that both types of B. inermis underwent floral initiation in the spring at Beaverlodge. Both types started development after April 26 of 1971 and 1972. It was concluded that temperature was the major factor governing the onset of floral development in B. inermis. The B. pumpellianus accessions all underwent floral initiation in the fall, prior to soil freeze-up. Polar bromegrass, which has both B. inermis and B. pumpellianus ancestry, behaved in a similar manner. There were small differences in the times at which floral development started. It is probable that day length is the prime factor governing floral initiation of B. pumpellianus and Polar bromegrass in the fall. On the basis of one year's seed yield data, it was suggested that Carlton and Redpatch should be seeded after mid-May but before mid-July when grown as seed crops at Beaverlodge. It was also found that plants which produced seed in the year following seeding had developed more than one tiller prior to freeze-up in the year of seeding. Larvae of Hylemya sp. were found to be damaging tiller bases and apical meristems of Bromus spp. The extent of the larval infestation varied seasonally and yearly.
Inertial range magnetic fluctuation anisotropy observed from PSP first seven orbits
Creators: name: Zhao, L. -L.
name: Zank, G. P.
name: Adhikari, L.
name: Nakanotani, M.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: Solar wind turbulence is anisotropic with respect to the mean magnetic field. Anisotropy leads to ambiguity when interpreting in-situ turbulence observations in the solar wind because an apparent change in the measurements could be due either to the change of intrinsic turbulence properties or to a simple change of the spacecraft sampling direction. We demonstrate the ambiguity using the spectral index and magnetic compressibility in the inertial range observed by the Parker Solar Probe during its first seven orbits ranging from 0.1 to 0.6 AU. To unravel the effects of the sampling direction, we assess whether the wavevector anisotropy is consistent with a two-dimensional (2D) plus slab turbulence transport model and determine the fraction of power in the 2D versus slab component. Our results confirm that the 2D plus slab model is consistent with the data and the power ratio between 2D and slab components depends on radial distance, with the relative power in 2D fluctuations becoming smaller closer to the Sun.
description: This paper is to be published in ApJL
Spin Correlation Effects in Top Quark Pair Production at the LHC
Creators: name: Mahlon, Gregory
name: Parke, Stephen J.
Publisher: name: arXiv
Year: 2010
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: At a 14 TeV proton-proton collider, the Large Hadron Collider (LHC), we show that top quark pair production is dominated at low invariant mass by the fusion of two like-helicity gluons, producing top quark pairs in the left-left or right-right helicity configurations. Whereas, at higher invariant mass the production is dominated by the fusion of unlike-helicity gluons, producing top quark pairs in the up-down or down-up off-diagonal configurations, identical to top quark pair production via quark-antiquark annihilation. We study in detail the low invariant mass region, and show that the spin correlations can be easily observed in this region by looking at the distribution of the difference in the azimuthal angles, Delta-phi, of the dileptons decay products of the top quarks in the laboratory frame. Due to the large cross section for top pair production at the LHC, even with a cut requiring that the invariant mass of the top quark pair be less than 400 GeV, the approximate yield would be 10^4 di-lepton (e, mu) events per fb^{-1} before detector efficiencies are applied. Therefore, there is ample statistics to form the Delta-phi distribution of the dilepton events, even with the invariant mass restriction. We also discuss possibilities for observing these spin correlations in the lepton plus jets channel.
description: 27 pages, 11 postscript figures. A trivial error in Fig 11 was corrected which does not affect the conclusions