cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Properties of the diffuse gas component in filaments detected in the Dianoga cosmological simulations
Creators: name: Ilc, Samo
name: Fabjan, Dunja
name: Rasia, Elena
name: Borgani, Stefano
name: Dolag, Klaus
Publisher: name: arXiv
Year: 2024
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Hydrodynamical cosmological simulations are ideal laboratories where the evolution of the cosmic web can be studied. This allows for easier insight into the nature of the filaments. We investigate how the intrinsic properties of filaments are evolving in areas extracted from a larger cosmological simulation. We aim to identify significant trends in the properties of Warm-Hot Intergalactic Medium (WHIM) and suggest possible explanations. To study the filaments and their contents, we select a subset of regions from the Dianoga simulation. We analysed these regions that were simulated with different baryon physics, namely with and without the AGN feedback. We construct the cosmic web using the Sub-space Constrained Mean Shift (SCMS) algorithm and the Sequential Chain Algorithm for Resolving Filaments (SCARF). We examined the basic physical properties of filaments (length, shape, mass, radius) and analysed different gas phases (hot, WHIM and colder gas components) within those structures. The evolution of the global filament properties and the properties of the gas phases were studied in the redshift range $0 < z < 1.48$. Within our simulations, the detected filaments have, on average, lengths below $9$ Mpc. The filaments' shape correlates with their length; the longer they are, the more likely they are curved. We find that the scaling relation between mass $M$ and length $L$ of the filaments is well described by the power law $M \propto L^{1.7}$. The radial density profile is widening with redshift, meaning that the radius of the filaments is getting larger over time. The fraction of gas mass in the WHIM phase does not depend on the model and is rising towards lower redshifts. However, the included baryon physics has a strong impact on the metallicity of gas in filaments, indicating that the AGN feedback impacts the metal content already at redshifts of $z \sim 2$.
description: 16 pages, 13 figures
Additional file 1 of Impact of posttransplant cyclophosphamide on the outcome of patients undergoing unrelated single-unit umbilical cord blood transplantation for pediatric acute leukemia
Creators: name: Li, Xin-Yu
name: Zhan, Li-Ping
name: Liu, Dian-Dian
name: Han, Xia-Wei
name: Chen, Han
name: Wu, Zheng-Zhou
name: Wang, Yin
name: Que, Li-Ping
name: Wu, Xiao-Jun
name: Liu, Su
name: Wang, Kai-Mei
name: Huang, Shao-Liang
name: Fang, Jian-Pei
name: Huang, Ke
name: Xu, Hong-Gui
Publisher: name: figshare
Year: 2022
Subjects: subject: Space Science
subject: Medicine
subject: Microbiology
subject: FOS: Biological sciences
subject: Cell Biology
subject: Pharmacology
subject: Biotechnology
subject: Science Policy
subject: Hematology

description: Additional file 1.
Decoupling for mixed-homogeneous polynomials in $\mathbb R^3$
Creators: name: Li, Jianhui
name: Yang, Tongou
Publisher: name: arXiv
Year: 2021
Subjects: subject: Classical Analysis and ODEs (math.CA)
subject: FOS: Mathematics
subject: 42B99 (Primary), 53A05 (Secondary)

description: We prove decoupling inequalities for mixed-homogeneous bivariate polynomials, which partially answers a conjecture of Bourgain, Demeter and Kemp.
description: 27 pages and 3 figures; to appear in Mathematische Annalen
A Data-Driven Model for the Field Emission from Broad-Area Electrodes
Creators: name: Borghei, Moein
name: Langtry, Robin
Publisher: name: arXiv
Year: 2024
Subjects: subject: Applied Physics (physics.app-ph)
subject: FOS: Physical sciences

description: Electron emission from cathodes in high field gradients is a quantum tunneling effect. The 1928 Fowler-Nordheim field emission (FE) equation and the 1956 Murphy-Good FE equation have traditionally been key in describing cold field emissions, offering estimates for emitters for almost a century. Nevertheless, applying FE theory in practice is often constrained by the lack of data on the distribution and geometry of the emission sites. Predictions become more challenging with an uneven electric field distribution at the cathode surface. Consequently, FE formulations are frequently calibrated using current-voltage data after test, limiting their efficacy as true predictive models.
 This study develops an alternative model for field emission using a data-driven predictive approach based on (1) vast experimental data, (2) electrostatic simulations of the cathode surface, and (3) detailed material and geometry properties, which together overcome these limitations. The objective of this work is to develop and harness this comprehensive dataset to train a machine learning model capable of providing precise predictions of the cathode current in order to further the understanding and application of field emission phenomena. More than 259 hours of experimental data have been processed to train and benchmark some of the well-known machine learning models. After two stages of optimization, a coefficient of determination >98% is achieved in the prediction total field emission current using ensemble models.
$μ-e$ conversion in nuclei within the CMSSM seesaw: universality versus non-universality
Creators: name: Arganda, E.
name: Herrero, M. J.
name: Teixeira, A. M.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: In this paper we study $μ-e$ conversion in nuclei within the context of the Constrained Minimal Supersymmetric Standard Model, enlarged by three right handed neutrinos and their supersymmetric partners, and where the neutrino masses are generated via a seesaw mechanism. Two different scenarios with either universal or non-universal soft supersymmetry breaking Higgs masses at the gauge coupling unification scale are considered. In the first part we present a complete one-loop computation of the conversion rate for this process that includes the photon-, $Z$-boson, and Higgs-boson penguins, as well as box diagrams, and compare their size in the two considered scenarios. Then, in these two scenarios we analyse the relevance of the various parameters on the conversion rates, particularly emphasising the role played by the heavy neutrino masses, $\tan β$, and especially $θ_{13}$. In the case of hierachical heavy neutrinos, an extremely high sensitivity of the rates to $θ_{13}$ is indeed found. The last part of this work is devoted to the study of the interesting loss of correlation between the $μ-e$ conversion and $μ\to e γ$ rates that occurs in the non-universal scenario. In the case of large $\tan β$ and light $H^0$ Higgs boson an enhanced ratio of the $μ-e$ to $μ\to e γ$ rates, with respect to the universal case is found, and this could be tested with the future experimental sensitivities.
description: 48 pages, 15 figures. Minor typos corrected and some references added
Aleochara (Xenochara) inexspectata Klimaszewski 1984
Creators: name: Webster, Reginald
name: Klimaszewski, Jan
name: Pelletier, Georges
name: Savard, Karine
Publisher: name: Zenodo
Year: 2009
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Staphylinidae
Aleochara
Aleochara inexspectata

description: Aleochara (Xenochara) inexspectata Klimaszewski, 1984 Fig 5, Map 5 New Records. CANADA, New Brunswick, Charlotte Co., near New River, 45.2122°N, 66.6160°W, 2.VI.2006 (2 ♁, RWC). Saint John Co., Dipper Harbour, 45.1169°N, 66.3771°W, 15.V.2006 (1 ♁, RWC). Bionomic Notes. Aleochara inexspectata was collected from fresh moose dung in an eastern white cedar swamp and in decaying sea wrack resting on vegetation on the upper margin of a salt marsh in New Brunswick. Adults were collected during May and June. Little was previously known about the bionomics of this rare species. Collection method: sifting. Distribution in Canada and Alaska. ON, QC, NB, NS (Klimaszewski 1984; Klimaszewski and Cervenka 1986; Gouix and Klimaszewski 2007). Map 5. Collection localities in New Brunswick, Canada of Aleochara inexspectata.
description: Published as part of Webster, Reginald, Klimaszewski, Jan, Pelletier, Georges & Savard, Karine, 2009, New Staphylinidae (Coleoptera) records with new collection data from New Brunswick, Canada. I. Aleocharinae, pp. 171-248 in ZooKeys 22 (22) on pages 179-180, DOI: 10.3897/zookeys.22.152, http://zenodo.org/record/576537
description: {"references": ["Klimaszewski J (1984) A revision of the genus Aleochara Gravenhorst of America north of Mexico (Coleoptera: Staphylinidae: Aleocharinae). Memoirs of the Entomological Society of Canada 129: 211 pp.", "Klimaszewski J, Cervenka VJ (1986) A revision of the genus Aleochara (Coleoptera: Staphylinidae) of America north of Mexico. Supplement 3. New distribution data. Entomological News 97: 119 - 120.", "Gouix N, Klimaszewski J (2007) Catalogue of Aleocharine Rove Beetles of Canada and Alaska (Coleoptera, Staphylinidae, Aleocharinae). Pensoft Publishers, Sofia-Moscow, 165 pp."]}
The SAURON project - XI. Stellar Populations from Absorption Line Strength Maps of 24 Early-Type Spirals
Creators: name: Peletier, Reynier F.
name: Falcon-Barroso, Jesus
name: Bacon, Roland
name: Cappellari, Michele
name: Davies, Roger L.
name: de Zeeuw, P. T.
name: Emsellem, Eric
name: Ganda, Katia
name: Krajnovic, Davor
name: Kuntschner, Harald
name: McDermid, Richard M.
name: Sarzi, Marc
name: van de Ven, Glenn
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present absorption line strength maps of a sample of 24 representative early-type spiral galaxies, mostly of type Sa, obtained as part of the SAURON survey of nearby galaxies using our custom-built integral-field spectrograph. Using high-quality spectra, spatially binned to a constant signal-to-noise, we measure several key age, metallicity and abundance ratio sensitive indices from the Lick/IDS system over a contiguous two-dimensional field including bulge and inner disc. We present maps of H beta, Fe 5015 and Mg b, for each galaxy The absorption line maps show that many galaxies contain some younger populations (<= 1 Gyr), distributed in small or large inner discs, or in circumnuclear star forming rings. In many cases these young stars are formed in circumnuclear mini-starbursts, which are dominating the light in the centres of some of the early-type spirals. These mini-starburst cause a considerable scatter in index-index diagrams such as Mg b- H beta and Mg b -Fe 5015, more than is measured for early-type galaxies. We find that the central regions of Sa galaxies display a wide range in ages, even within the galaxies. 50% of the sample show velocity dispersion drops in their centres. All of the galaxies of our sample lie on or below the Mg b- $σ$ relation for elliptical galaxies in the Coma cluster, and above the H beta absorption line - $σ$ relation for elliptical galaxies. If those relations are considered to be relations for the oldest local galaxies we see that our sample of spirals has a considerable scatter in age, with the largest scatter at the lowest $σ$. This is in disagreement with highly inclined samples, in which generally only old stellar populations are found in the central regions. All this can be understood if ... (see paper for rest of abstract)
description: Accepted for publication in MNRAS, 29 pages, 10 figures. Paper with Figures at full resolution available at http://www.strw.leidenuniv.nl/sauron/
Detection of a new sample of Galactic White Dwarfs in the direction of the Small Magellanic Cloud
Creators: name: Sidharth, A. V.
name: Shridharan, B.
name: Mathew, Blesson
name: Devaraj, A.
name: Cysil, T. B.
name: Stalin, C. S.
name: Arun, R.
name: Bhattacharyya, Suman
name: Kartha, Sreeja S.
name: Robin, T.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: In this study, we demonstrate the efficacy of the Ultraviolet Imaging Telescope (UVIT) in identifying and characterizing white dwarfs (WDs) within the Milky Way Galaxy. Leveraging the UVIT point source catalogue towards SMC and crossmatching with Gaia DR3 data, we identified 43 single WDs (37 new detections), 13 new WD+main sequence (MS) candidates and 161 UV bright MS stars by analysing their Spectral Energy Distributions (SED). Using the WD evolutionary models, we determine the masses, effective temperatures, and cooling ages of these identified WDs. Masses of these WDs range from 0.2 to 1.3 M$_{\odot}$ and effective temperatures (T$_{eff}$) between 10000 K to 15000 K, with cooling ages spanning 0.1 to 2 Gyr. Notably, we detect hotter WDs compared to literature values, which is attributed to the sensitivity of UVIT. Furthermore, we report the detection of 20 new extremely low-mass (ELM) candidates from our analysis. Future spectroscopic studies of the ELM candidates will help us understand the formation scenarios of these exotic objects. Despite limitations in Gaia DR3 distance measurements for optically faint WDs, we provide a crude estimate of the WD space density within 1kpc as 1.3 $\times$ 10$^{-3}$ pc$^{-3}$, which is higher than previous estimates in the literature. Our results underscore the instrumental capabilities of UVIT and anticipate the forthcoming UV missions like INSIST for systematic WD discovery. Our methodology sets a precedent for future analyses in other UVIT fields to find more WDs and perform spectroscopic studies to verify their candidacy.
description: Accepted for publication in Astronomy & Astrophysics
Statistical interactions and boson-anyon duality in fractional quantum Hall fluids
Creators: name: Yang, Bo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present an exact scheme of bosonization for anyons (including fermions) in the two-dimensional manifold of the quantum Hall fluid. This gives every fractional quantum Hall phase of the electrons one or more dual bosonic descriptions. For interacting electrons, the statistical transmutation from anyons to bosons allows us to explicitly derive the microscopic statistical interaction between the anyons, in the form of the effective two-body and few-body interactions. This also leads to a number of unexpected topological phases of the single component bosonic fractional quantum Hall effect that may be experimentally accessible. Numerical analysis of the energy spectrum and ground state entanglement properties are carried out for simple examples.
description: 4+ pages, 2 figures, comments very welcome
Universal Control of Nuclear Spins Via Anisotropic Hyperfine Interactions
Creators: name: Hodges, Jonathan S.
name: Yang, Jamie C.
name: Ramanathan, Chandrasekhar
name: Cory, David G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We show that nuclear spin subsystems can be completely controlled via microwave irradiation of resolved anisotropic hyperfine interactions with a nearby electron spin. Such indirect addressing of the nuclear spins via coupling to an electron allows us to create nuclear spin gates whose operational time is significantly faster than conventional direct addressing methods. We experimentally demonstrate the feasibility of this method on a solid-state ensemble system consisting of one electron and one nuclear spin.
description: RevTeX4, 8 pages, 8 figures
Improved Schwinger-DeWitt techniques for higher-derivative perturbations of operator determinants
Creators: name: Anselmi, Damiano
name: Benini, Anna
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider higher-derivative perturbations of quantum gravity and quantum field theories in curved space and investigate tools to calculate counterterms and short-distance expansions of Feynman diagrams. In the case of single higher-derivative insertions we derive a closed formula that relates the perturbed one-loop counterterms to the unperturbed Schwinger-DeWitt coefficients. In the more general case, we classify the contributions to the short-distance expansion and outline a number of simplification methods. Certain difficulties of the common differential technique in the presence of higher-derivative perturbations are avoided by a systematic use of the Campbell-Baker-Hausdorff formula, which in some cases reduces the computational effort considerably.
description: 18 pages
Dynamical breaking of U(1)_{R} and supersymmetry in a metastable vacuum
Creators: name: Abel, Steven
name: Durnford, Callum
name: Jaeckel, Joerg
name: Khoze, Valentin V.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider the metastable N=1 QCD model of Intriligator, Seiberg and Shih (ISS), deformed by adding a baryon term to the superpotential. This simple deformation causes the spontaneous breaking of the approximate R-symmetry of the metastable vacuum. We then gauge the flavour SU(5)_f and identify it with the parent gauge symmetry of the Standard Model (SM). This implements direct mediation of supersymmetry breaking without the need for an additional messenger sector. A reasonable choice of parameters leads to gaugino masses of the right order. Finally, we speculate that the entire ``ISS x SM'' model should be interpreted as a magnetic dual of an (unknown) asymptotically free theory.
description: 11 pages, 3 figures. v2 improved discussion of the gaugino masses
The 2d Gross-Neveu Model at Finite Temperature and Density with Finite Corrections
Creators: name: Kneur, Jean-Loic
name: Pinto, Marcus Benghi
name: Ramos, Rudnei O.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Other Condensed Matter (cond-mat.other)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We use the linear $δ$ expansion, or optimized perturbation theory, to evaluate the effective potential for the two dimensional Gross-Neveu model at finite temperature and density obtaining analytical equations for the critical temperature, chemical potential and fermionic mass which include finite $N$ corrections. Our results seem to improve over the traditional large-N predictions.
description: 7 pages, 8 figures
title:  Tenere viva la memoria. Il tentativo inane dello storico e la lezione di Maurice Halbwachs
Creators: name: Tedesco, Luca
Publisher: name: Roma TrE-Press
Year: 2021

description: Scopo del saggio è mostrare come la storiografia, nella misura in cui utilizza la memoria per veicolare una specifica costellazione valoriale, incorra in un duplice infortunio scientifico, non tenendo sufficientemente conto delle differenze tra memoria e indagine storica, esplicitate da Maurice Halbwachs, e attribuendosi compiti impropri.
description: Maurice Halbwachs e la memoria collettiva. Riletture critiche
Supersymmetric Unparticle Effects on Higgs Boson Mass and Dark Matter
Creators: name: Deshpande, N. G.
name: He, Xiao-Gang
name: Jiang, Jing
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We propose a model that introduces a supersymmetric unparticle operator in the minimal supersymmetric Standard Model. We analyze the lowest dimension operator involving an unparticle. This operator behaves as a Standard Model gauge singlet and it introduces a new parameter into the Higgs potential which can provide an alternative way to relax the upper limit on the lightest Higgs boson mass. This operator also introduces several unparticle interactions which can induce a neutral Higgsino to decay into a spinor unparticle. It also induces violation of scale invariance around the electroweak scale. It is necessary for the scale of this violation to be larger than the lightest supersymmetric particle mass to maintain the latter as the usual weakly interacting massive particle dark matter candidate. An alternative is to have unparticle state as dark matter candidate. We also comment on some collider implications.
description: 9 pages, 1 figure; typos corrected
Determination of the up/down-quark mass within QCD sum rules in the scalar channel
Creators: name: Yin, Fang-Hui
name: Tian, Wen-Ya
name: Tang, Liang
name: Guo, Zhi-Hui
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: In this work, we determine up/down-quark mass $m_{q=u/d}$ in the isoscalar scalar channel from both the Shifman-Vainshtein-Zakharov (SVZ) and the Monte-Carlo-based QCD sum rules. The relevant spectral function, including the contributions from the $f_0(500)$, $f_0(980)$ and $f_0(1370)$ resonances, is determined from a sophisticated $U(3)$ chiral study. Via the traditional SVZ QCD sum rules, we give the prediction to the average light-quark mass $m_q(2 \, \text{GeV})=\frac{1}{2}(m_u(2 \, \text{GeV}) + m_d(2 \, \text{GeV}))=(3.46^{+0.16}_{-0.22} \pm 0.33) \, \text{MeV}$. Meanwhile, by considering the uncertainties of the input QCD parameters and the spectral functions of the isoscalar scalar channel, we obtain $m_q (2\, \text{GeV}) = (3.44 \pm 0.14 \pm 0.32) \, \text{MeV}$ from the Monte-Carlo-based QCD sum rules. Both results are perfectly consistent with each other, and nicely agree with the Particle Data Group value within the uncertainties.
description: 25 pages,7 figures,2 tables
Implementation of weak measurement amplification with the weak coherent light and optomechanical system
Creators: name: Li, Gang
name: Yang, Wen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Most studies for postselected weak measurement in optomechanical system focus on using a single photon as a measured system. However, we find that using weak coherent light instead of a single photon can also amplify the mirror's position displacement of one photon. In the WVA regime (Weak Value Amplification regime), the weak value of one photon can lie outside the eigenvalue spectrum, proportional to the difference of the mirror's position displacement between the successful and failed postselection and its successful postselection probability is dependent of the mean photon number of the coherent light and improved by adjusting it accordingly. Outside the WVA regime, the amplification limit can reach the level of the vacuum fluctuations, and when the mean photon number and the optomechanical coupling parameter are selected appropriately, its successful postselection probability becomes higher, which is beneficial to observe the maximum amplification value under the current experimental conditions. This result breaks the constraint that it is difficult to detect outside the WVA regime. This opens up a new regime for the study of a single photon nonlinearity in optomechanical system.
description: 9 pages
Dynamical Friction and Galaxy Merging Timescales
Creators: name: Boylan-Kolchin, Michael
name: Ma, Chung-Pei
name: Quataert, Eliot
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The timescale for galaxies within merging dark matter halos to merge with each other is an important ingredient in galaxy formation models. Accurate estimates of merging timescales are required for predictions of astrophysical quantities such as black hole binary merger rates, the build-up of stellar mass in central galaxies, and the statistical properties of satellite galaxies within dark matter halos. In this paper, we study the merging timescales of extended dark matter halos using N-body simulations. We compare these results to standard estimates based on the Chandrasekhar theory of dynamical friction. We find that these standard predictions for merging timescales, which are often used in semi-analytic galaxy formation models, are systematically shorter than those found in simulations. The discrepancy is approximately a factor of 1.7 for $M_sat/M_host \approx 0.1$ and becomes larger for more disparate satellite-to-host mass ratios, reaching a factor of $\sim 3.3$ for $M_sat/M_host\approx 0.01$. Based on our simulations, we propose a new, easily implementable fitting formula that accurately predicts the timescale for an extended satellite to sink from the virial radius of a host halo down to the halo's center for a wide range of $M_sat/M_host$ and orbits. Including a central bulge in each galaxy changes the merging timescale by $\la 10%$. To highlight one concrete application of our results, we show that merging timescales often used in the literature overestimate the growth of stellar mass by satellite accretion by $\approx 40 %$, with the extra mass gained in low mass ratio mergers.
description: 10 pages, 7 figures; MNRAS, in press. Minor revisions, including results from additional simulations with baryonic components; conclusions unchanged
The influence of $δ$ meson on the isospin splitting of in-medium $NN\to NΔ$ cross sections
Creators: name: Cui, Ying
name: Zhang, Yingxun
name: Tian, Yuan
name: Li, Zhuxia
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: The isospin splitting of the in-medium $NN\rightarrow NΔ$ cross sections in asymmetric nuclear medium are investigated in the framework of the one-boson exchange model by including $δ$ and $ρ$ mesons. Our results show that the medium correction factors $R=σ_{ NN\rightarrow NΔ}^*/σ_{NN\rightarrow NΔ}^{\text{free}}$ have $R_{pp \to nΔ^{++}} < R_{nn \to pΔ^{-}}$ and $R_{NN \to NΔ^{+}} R_{nn \to pΔ^{-}}$ and $R_{NN \to NΔ^{+}} >R_{NN \to NΔ^{0}}$.
description: 15 pages, 4 figures
Scaling in the Fan of an Unconventional Quantum Critical Point
Creators: name: Melko, Roger G.
name: Kaul, Ribhu K.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We present results of extensive finite-temperature Quantum Monte Carlo simulations on a SU(2) symmetric S=1/2 quantum antiferromagnet with a four-spin interaction [Sandvik, Phys. Rev. Lett. 98, 227202 (2007)]. Our simulations, which are free of the sign-problem and carried out on lattices containing in excess of 1.6 X 10^4 spins, indicate that the four-spin interaction destroys the Néel order at an unconventional z=1 quantum critical point, producing a valence-bond solid paramagnet. Our results are consistent with the `deconfined quantum criticality' scenario.
description: published version, minor changes
Statistical uncertainties of the $v_{n}\{2k\}$ harmonics from Q-cumulants
Creators: name: Nadderd, L.
name: Milosevic, J.
name: Wang, F.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: Analytic formulas to calculate statistical uncertainties of $v_{n}\{2k\}$ harmonics extracted from the Q-cumulants are presented. The Q-cumulants are multivariate polynomial functions of the weighted means of $2m$-particle azimuthal correlations, $\llangle 2m \rrangle$. Variances and covariances of the $\llangle 2m \rrangle$ are included in the analytic formulas of the uncertainties that can be calculated simultaneously with the calculations of the $v_{n}\{2k\}$ harmonics. The calculations are performed using a simple toy model which roughly simulates elliptic flow azimuthal anisotropy with magnitudes around 0.05. The results are compared with the results obtained by the many data sub-sets, and by the bootstrapping method. The first one is a common way of estimation of the statistical uncertainties of the $v_{n}\{2k\}$ harmonics in a real experiment. In order to increase precision in the measurement of the $v_{n}\{2k\}$ harmonics, a large number of 15000 sub-sets and the same number of the re-sampling in the bootstrap method is used. A very good agreement in the comparison with the proposed way of the analytic calculation of the $v_{n}\{2k\}$ statistical uncertainties is found. Additionally, a recurrence equation for Q-cumulants calculation is also presented.
description: 8 pages, 9 figures
Interactions and star formation activity in Wolf-Rayet galaxies
Creators: name: López-Sánchez, Ángel R.
name: Esteban, César
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present the main results of the PhD Thesis carried out by López-Sánchez (2006), in which a detailed morphological, photometrical and spectroscopical analysis of a sample of 20 Wolf-Rayet (WR) galaxies was realized. The main aims are the study of the star formation and O and WR stellar populations in these galaxies and the role that interactions between low surface companion objects have in the triggering of the bursts. We analyze the morphology, stellar populations, physical conditions, chemical abundances and kinematics of the ionized gas, as well as the star-formation activity of each system.
description: 16 pages, 15 figures
Decomposing Dusty Galaxies. I. Multi-Component Spectral Energy Distribution Fitting
Creators: name: Marshall, J. A.
name: Herter, T. L.
name: Armus, L.
name: Charmandaris, V.
name: Spoon, H. W. W.
name: Bernard-Salas, J.
name: Houck, J. R.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We present a new multi-component spectral energy distribution (SED) decomposition method and use it to analyze the ultraviolet to millimeter wavelength SEDs of a sample of dusty infrared-luminous galaxies. SEDs are constructed from spectroscopic and photometric data obtained with the Spitzer Space Telescope, in conjunction with photometry from the literature. Each SED is decomposed into emission from populations of stars, an AGN accretion disk, PAHs, atomic and molecular lines, and distributions of graphite and silicate grains. Decompositions of the SEDs of the template starburst galaxies NGC7714 and NGC2623 and the template AGNs PG0804+761 and Mrk463 provide baseline properties to aid in quantifying the strength of star-formation and accretion in the composite systems NGC6240 and Mrk1014. We find that obscured radiation from stars is capable of powering the total dust emission from NGC6240, although we cannot rule out a contribution from a deeply embedded AGN visible only in X-rays. The decomposition of Mrk1014 is consistent with ~65% of its power emerging from an AGN and ~35% from star-formation. We suggest that many of the variations in our template starburst SEDs may be explained in terms of the different mean optical depths through the clouds of dust surrounding the young stars within each galaxy. Prompted by the divergent far-IR properties of our template AGNs, we suggest that variations in the relative orientation of their AGN accretion disks with respect to the disks of the galaxies hosting them may result in different amounts of AGN-heated cold dust emission emerging from their host galaxies. We estimate that 30-50% of the far-IR and PAH emission from Mrk1014 may originate from such AGN-heated material in its host galaxy disk.
description: 27 pages, 12 figures. Accepted for publication in the ApJ
Two-body transients in coupled atomic-molecular BECs
Creators: name: Naidon, Pascal
name: Tiesinga, Eite
name: Julienne, Paul S.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We discuss the dynamics of an atomic Bose-Einstein condensate when pairs of atoms are converted into molecules by single-color photoassociation. Three main regimes are found and it is shown that they can be understood on the basis of time-dependent two-body theory. In particular, the so-called rogue dissociation regime [Phys. Rev. Lett., 88, 090403 (2002)], which has a density-dependent limit on the photoassociation rate, is identified with a transient regime of the two-atom dynamics exhibiting universal properties. Finally, we illustrate how these regimes could be explored by photoassociating condensates of alkaline-earth atoms.
description: 4 pages, 3 figures - typos corrected in formulae
Magnetism in graphene nano-islands
Creators: name: Fernandez-Rossier, J.
name: Palacios, J. J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We study the magnetic properties of nanometer-sized graphene structures with triangular and hexagonal shapes terminated by zig-zag edges. We discuss how the shape of the island, the imbalance in the number of atoms belonging to the two graphene sublattices, the existence of zero-energy states, and the total and local magnetic moment are intimately related. We consider electronic interactions both in a mean-field approximation of the one-orbital Hubbard model and with density functional calculations. Both descriptions yield values for the ground state total spin, $S$, consistent with Lieb's theorem for bipartite lattices. Triangles have a finite $S$ for all sizes whereas hexagons have S=0 and develop local moments above a critical size of $\approx 1.5$ nm.
description: Published version
MemX: An Attention-Aware Smart Eyewear System for Personalized Moment Auto-capture
Creators: name: Chang, Yuhu
name: Zhao, Yingying
name: Dong, Mingzhi
name: Wang, Yujiang
name: Lu, Yutian
name: Lv, Qin
name: Dick, Robert P.
name: Lu, Tun
name: Gu, Ning
name: Shang, Li
Publisher: name: arXiv
Year: 2021
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: This work presents MemX: a biologically-inspired attention-aware eyewear system developed with the goal of pursuing the long-awaited vision of a personalized visual Memex. MemX captures human visual attention on the fly, analyzes the salient visual content, and records moments of personal interest in the form of compact video snippets. Accurate attentive scene detection and analysis on resource-constrained platforms is challenging because these tasks are computation and energy intensive. We propose a new temporal visual attention network that unifies human visual attention tracking and salient visual content analysis. Attention tracking focuses computation-intensive video analysis on salient regions, while video analysis makes human attention detection and tracking more accurate. Using the YouTube-VIS dataset and 30 participants, we experimentally show that MemX significantly improves the attention tracking accuracy over the eye-tracking-alone method, while maintaining high system energy efficiency. We have also conducted 11 in-field pilot studies across a range of daily usage scenarios, which demonstrate the feasibility and potential benefits of MemX.
description: Proceedings of the ACM on Interactive, Mobile, Wearable and Ubiquitous Technologies (IMWUT)
Constraints on anomalous Higgs boson couplings to vector bosons and fermions in its production and decay using the four-lepton final state
Creators: name: CMS Collaboration
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Experiment (hep-ex)
subject: FOS: Physical sciences

description: Studies of $CP$ violation and anomalous couplings of the Higgs boson to vector bosons and fermions are presented. The data were acquired by the CMS experiment at the LHC and correspond to an integrated luminosity of 137 fb$^{-1}$ at a proton-proton collision energy of 13 TeV. The kinematic effects in the Higgs boson's four-lepton decay H $\to$ 4$\ell$ and its production in association with two jets, a vector boson, or top quarks are analyzed, using a full detector simulation and matrix element techniques to identify the production mechanisms and to increase sensitivity to the Higgs boson tensor structure of the Higgs boson interactions. A simultaneous measurement is performed of up to five Higgs boson couplings to electroweak vector bosons (HVV), two couplings to gluons (Hgg), and two couplings to top quarks (Htt). The $CP$ measurement in the Htt interaction is combined with the recent measurement in the H $\to$ $γγ$ channel. The results are presented in the framework of anomalous couplings and are also interpreted in the framework of effective field theory, including the first study of $CP$ properties of the Htt and effective Hgg couplings from a simultaneous analysis of the gluon fusion and top-associated processes. The results are consistent with the standard model of particle physics.
description: Replaced with the published version. Added the journal reference and the DOI. All the figures and tables can be found at http://cms-results.web.cern.ch/cms-results/public-results/publications/HIG-19-009 (CMS Public Pages)
Dimensionality Reduction and Nearest Neighbors for Improving Out-of-Distribution Detection in Medical Image Segmentation
Creators: name: Woodland, McKell
name: Patel, Nihil
name: Castelo, Austin
name: Taie, Mais Al
name: Eltaher, Mohamed
name: Yung, Joshua P.
name: Netherton, Tucker J.
name: Calderone, Tiffany L.
name: Sanchez, Jessica I.
name: Cleere, Darrel W.
name: Elsaiey, Ahmed
name: Gupta, Nakul
name: Victor, David
name: Beretta, Laura
name: Patel, Ankit B.
name: Brock, Kristy K.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Computer and information sciences

description: Clinically deployed deep learning-based segmentation models are known to fail on data outside of their training distributions. While clinicians review the segmentations, these models tend to perform well in most instances, which could exacerbate automation bias. Therefore, detecting out-of-distribution images at inference is critical to warn the clinicians that the model likely failed. This work applied the Mahalanobis distance (MD) post hoc to the bottleneck features of four Swin UNETR and nnU-net models that segmented the liver on T1-weighted magnetic resonance imaging and computed tomography. By reducing the dimensions of the bottleneck features with either principal component analysis or uniform manifold approximation and projection, images the models failed on were detected with high performance and minimal computational load. In addition, this work explored a non-parametric alternative to the MD, a k-th nearest neighbors distance (KNN). KNN drastically improved scalability and performance over MD when both were applied to raw and average-pooled bottleneck features.
description: Accepted for publication at the Journal of Machine Learning for Biomedical Imaging (MELBA) https://melba-journal.org/2024:020. Expansion of "Dimensionality Reduction for Improving Out-of-Distribution Detection in Medical Image Segmentation" arXiv:2308.03723. Code available at https://github.com/mckellwoodland/dimen_reduce_mahal (https://zenodo.org/records/13881989)
A comprehensive study of Cepheid variables in the Andromeda galaxy. Period distribution, blending and distance determination
Creators: name: Vilardell, F.
name: Jordi, C.
name: Ribas, I.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: Extragalactic Cepheids are the basic rungs of the cosmic distance scale. They are excellent standard candles, although their luminosities and corresponding distance estimates can be affected by the particular properties of the host galaxy. Therefore, the accurate analysis of the Cepheid population in other galaxies, and notably in the Andromeda Galaxy (M31), is crucial to obtaining reliable distance determinations. We obtained accurate photometry (in B and V passbands) of 416 Cepheids in M31 over a five year campaign within a survey aimed at the detection of eclipsing binaries. The resulting Cepheid sample is the most complete in M31 and has almost the same period distribution as the David Dunlap Observatory sample in the Milky Way. The large number of epochs (~250 per filter) has permitted the characterisation of the pulsation modes of 356 Cepheids, with 281 of them pulsating in the fundamental mode and 75 in the first overtone. The period-luminosity relationship of the fundamental mode Cepheids has been studied and a new approach has been used to estimate the effect of blending. We find that the blending contribution is as important as the metallicity correction when computing Cepheid distance determinations to M31 (~0.1 mag). Since large amplitude Cepheids are less affected by blending, we have used those with an amplitude A_V>0.8 mag to derive a distance to M31 of (m-M)_0=24.32+/-0.12 mag.
description: 10 pages, 9 figures; accepted for publication in A&A
Dynamical Complexity, Intermittent Turbulence, Coarse-Grained Dissipation, Criticality and Multifractal Processes
Creators: name: Chang, Tom
name: Wu, Cheng-chin
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The ideas of dynamical complexity induced intermittent turbulence by sporadic localized interactions of coherent structures are discussed. In particular, we address the phenomenon of magnetic reconfiguration due to coarse-grained dissipation as well as the interwoven connection between criticality and multifractal processes. Specific examples are provided.
description: 6 pages, 2 figures, submitted to AIP Conference Proceedings for the 6th Annual International Astrophysics Conference, Honolulu, March 16-22, 2007
Bounds on quark mass matrices elements due to measured properties of the mixing matrix and present values of the quark masses
Creators: name: Chaturvedi, S.
name: Gupta, V.
name: Sanchez-Colon, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We obtain constraints on possible structures of mass matrices in the quark sector by using as experimental restrictions the determined values of the quark masses at the $M_Z$ energy scale, the magnitudes of the quark mixing matrix elements $V_{\rm ud}$, $V_{\rm us}$, $V_{\rm cd}$, and $V_{\rm cs}$, and the Jarlskog invariant $J(V)$. Different cases of specific mass matrices are examined in detail. The quality of the fits for the Fritzsch and Stech type mass matrices is about the same with $χ^2/{\rm dof}=4.23/3=1.41$ and $χ^2/{\rm dof}=9.10/4=2.28$, respectively. The fit for a simple generalization (one extra parameter) of the Fritzsch type matrices, in the physical basis, is much better with $χ^2/{\rm dof}=1.89/4=0.47$. For comparison we also include the results using the quark masses at the 2 GeV energy scale. The fits obtained at this energy scale are similar to that at $M_Z$ energy scale, implying that our results are unaffected by the evolution of the quark masses from 2 to 91 GeV.
description: Evolution effects included
The effect of mood context on implicit remembering
Creators: name: Ryan, Lee
Publisher: name: University of British Columbia
Year: 2010

description: Two experiments were conducted to investigate whether mood dependent remembering occurs in situations where remembering is unintentional, or implicit. Experimentally induced moods (happy and sad) were used to create a distinctive context during the study and test sessions. In Experiment 1, performance on two implicit tasks, picture identification and category production, was examined when mood context was similar and dissimilar from study to test. Experiment 2 used a modified version of picture identification, and contrasted an explicit task (free recall) with an implicit task (word stem completion). The results are briefly discussed within a framework of transfer appropriate processing.
Requests by a mainstreamed student who is hearing impaired when interacting with peers
Creators: name: Ruddick, Lana B.
Publisher: name: University of British Columbia
Year: 2010

description: The purpose of this study was to test the applicability of the Effective Speaker Model (Wilkinson & Calculator, 1982) in assessing the nature of requests and responses of a 10-year-old student who is hearing impaired when interacting with peers in the regular classroom during student-directed activities. Requests are considered to be an important aspect of interaction in the classroom as receiving appropriate responses to requests has been shown to influence a student both academically and socially. The observational data were obtained using ethnographic research strategies. The requests were coded using an adapted system to that developed by Wilkinson and Calculator (1982) as being on-task, sincere, direct, directed to a designated listener, revised when initially unsuccessful, clarification requested, and whether or not appropriate responses were received. The frequency percentage for each of the characteristics and appropriate responses were calculated, and a profile created. Specific information from field notes and participant interviews were used to describe and substantiate the configuration. The coding and description were found to yield useful information regarding the characterisitics of a student's requests and responses to peers. Along with the characteristics outlined in the model, requests for clarification were found to be an additional characteristic to be included when considering the requests and responses of a student who is hearing impaired. In this case study, the student received appropriate responses to his requests 64% of the time after an initial request or after a revision. His requests were found to be generally on-task, direct, and designated to a listener. However, when the student's requests were not sincere, he did not receive appropriate responses from his peers. He revised his requests in various ways when they were initially unsuccessful although he did not always persist with revisions. Finally, the student was found to request clarification in a number of ways when persisting with understanding a peer response. The information provided by the model would lead to direct intervention and instruction for increasing the likelihood that the student will receive appropriate responses to requests. This research would seem to have implications for teachers and students who are hearing impaired in all educational settings.
Compositional Thinking in Cyberphysical Systems Theory
Creators: name: Bakirtzis, Georgios
name: Subrahmanian, Eswaran
name: Fleming, Cody H.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Systems and Control (eess.SY)
subject: Logic in Computer Science (cs.LO)
subject: Category Theory (math.CT)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences
subject: FOS: Mathematics

description: Engineering safe and secure cyber-physical systems requires system engineers to develop and maintain a number of model views, both dynamic and static, which can be seen as algebras. We posit that verifying the composition of requirement, behavioral, and architectural models using category theory gives rise to a strictly compositional interpretation of cyber-physical systems theory, which can assist in the modeling and analysis of safety-critical cyber-physical systems.