cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Quantum critical behavior of a magnetic quantum paraelectric
Creators: name: Das, Nabyendu
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: We discuss the interplay between anti-ferromagnetic order and polarization fluctuations in a magnetic quantum paraelectric. Using an action where anti-ferromagnetic order parameter couples to the polarization fluctuations and as well as magnetic field, we derive a set of self consistent equations to study both the temperature and the magnetic field dependence of the static dielectric susceptibility. The temperature dependence of dielectric susceptibility near both the anti-ferromagnetic quantum critical point and ferroelectric quantum critical point are described using scaling arguments. Discussions on achieving various quantum critical points in experiments are also made.
description: Published version, 7 pages, 3 figures; http://dx.doi.org/10.1016/j.physleta.2012.07.012
1/f Noise Analysis for FAST HI Intensity Mapping Drift-Scan Experiment
Creators: name: Hu, Wenkai
name: Li, Yichao
name: Wang, Yougang
name: Wu, Fengquan
name: Zhang, Bo
name: Zhu, Ming
name: Zuo, Shifan
name: Lagache, Guilaine
name: Ma, Yinzhe
name: Santos, Mario G.
name: Chen, Xuelei
Publisher: name: arXiv
Year: 2021
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We investigate the 1/f noise of the Five-hundred-meter Aperture Spherical Telescope (FAST) receiver system using drift-scan data from an intensity mapping pilot survey. All the 19 beams have 1/f fluctuations with similar structures. Both the temporal and the 2D power spectrum densities are estimated. The correlations directly seen in the time series data at low frequency $f$ are associated with the sky signal, perhaps due to a coupling between the foreground and the system response. We use Singular Value Decomposition (SVD) to subtract the foreground. By removing the strongest components, the measured 1/f noise power can be reduced significantly. With 20 modes subtraction, the knee frequency of the 1/f noise in a 10 MHz band is reduced to $1.8 \times 10^{-3}\Hz$, well below the thermal noise over 500-seconds time scale. The 2D power spectra show that the 1/f-type variations are restricted to a small region in the time-frequency space and the correlations in frequency can be suppressed with SVD modes subtraction. The residual 1/f noise after the SVD mode subtraction is uncorrelated in frequency, and a simple noise diode frequency-independent calibration of the receiver gain at 8s interval does not affect the results. The 1/f noise can be important for HI intensity mapping, we estimate that the 1/f noise has a knee frequency $(f_{k}) \sim$ 6 $\times$ 10$^{-4}$Hz, and time and frequency correlation spectral indices $(α) \sim 0.65$, $(β) \sim 0.8$ after the SVD subtraction of 30 modes. This can bias the HI power spectrum measurement by 10 percent.
description: 13 pages,17 figures, MNRAS accepted
Locality and entanglement harvesting in covariantly bandlimited scalar fields
Creators: name: Funai, Nicholas
name: Menicucci, Nicolas C.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Considerations of high energies in quantum field theories on smooth manifolds have led to generalized uncertainty principles and the possibility of a physical minimal length in quantum gravitational scenarios. In these models, the minimal length would be a physical limit, not just a mathematical tool, and should be Lorentz invariant. In this paper, we study two-qubit communication and entanglement harvesting in a field subject to a covariant bandlimit (minimum length) and present the changes induced by this bandlimit. We find the bandlimit introduces nonlocality and acausal communication in a manner unlike non-covariant bandlimits or other quantum optical approximations. We also observe that this covariant bandlimit introduces uncertainties in time and temporal ordering with the unusual behavior attributed to the behavior of virtual particles being modified by the covariant cutoff.
description: 20 pages (10 + 10 pages of Appendices). 6 figures. RevTeX 4.2
การเปรียบเทียบการใช้นวัตกรรมการออกแบบกลุ่มอาคารด้วยการใช้ Form-Based Codes กรณีศึกษาเมืองเดนเวอร์ (สหรัฐอเมริกา) ฮ่องกง (สาธารณรัฐประชาชนจีน) และภูเก็ต (ประเทศไทย)
Creators: name: กนกวรรณ มะสุวรรณ
Publisher: name: Thammasat University
Year: 2021
Subjects: นวัตกรรมออกแบบกลุ่มอาคาร
ข้อกําหนดมาตรการผังเมืองและรายละเอียดทางกายภาพ
การพัฒนาชุมชนเมืองอย่างยั่งยืน

description: Journal of Architectural/Planning Research and Studies, 18, 1, 21-40
Vertex Corrections and the Korringa Ratio in Strongly Correlated Electron Materials
Creators: name: Yusuf, Eddy
name: Powell, B. J.
name: McKenzie, Ross H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We show that the Korringa ratio, associated with nuclear magnetic resonance in metals, is unity if vertex corrections for the dynamic spin susceptibility are negligible and the hyperfine coupling is momentum independent. In the absence of vertex corrections we also find a Korringa behaviour for $T_1$, the nuclear spin relaxation rate, i.e., $1/T_1\propto T$, and a temperature independent Knight shift. These results are independent of the form and magnitude of the self-energy (so far as is consistent with neglecting vertex corrections) and of the dimensionality of the system.
description: 5 pages. accepted for publication in J. Phys.: Condens. Matter
Optimal Power and Time Allocation for WPCNs with Piece-wise Linear EH Model
Creators: name: Pejoski, Slavche
name: Hadzi-Velkov, Zoran
name: Schober, Robert
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: We propose a novel transmission protocol for harvest-then-transmit wireless powered communication networks, which takes into account the non-linearity of the energy harvesting (EH) process at the EH users and maximizes the sum rate in the uplink. We assume a piece-wise linear energy harvesting model and provide expressions for the optimal transmit power of the base station (BS), the duration of the EH phase, and the duration of the uplink information transmission phases of the users. The obtained solution provides insight regarding the significance of the non-linear EH model on the optimal resource allocation. Simulations unveil the growing impact of the saturation effect, which occurs for high received radio frequency powers, as the average and the maximum instantaneous transmit powers of the BS increase.
Emergent non-Hermitian conservation laws at exceptional points
Creators: name: Wang, Zuo
name: He, Liang
Publisher: name: arXiv
Year: 2024
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Non-Hermitian systems can manifest rich static and dynamical properties at their exceptional points (EPs). Here, we identify yet another class of distinct phenomena that is hinged on EPs, namely, the emergence of a series of non-Hermitian conservation laws. We demonstrate these distinct phenomena concretely in the non-Hermitian Heisenberg chain and formulate a general theory for identifying these emergent non-Hermitian conservation laws at EPs. By establishing a one-to-one correspondence between the constant of motions at EPs and those in corresponding auxiliary Hermitian systems, we trace their physical origin back to the presence of emergent symmetries in the auxiliary systems. Concrete simulations on quantum circuits show that these emergent conserved dynamics can be readily observed in current digital quantum computing systems.
description: 5+6 pages, 3+1 figures
Semantic-Enabled 6G Communication: A Task-oriented and Privacy-preserving Perspective
Creators: name: Guo, Shuaishuai
name: Zhang, Anbang
name: Wang, Yanhu
name: Feng, Chenyuan
name: Quek, Tony Q. S.
Publisher: name: arXiv
Year: 2024
Subjects: subject: Signal Processing (eess.SP)
subject: Systems and Control (eess.SY)
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Task-oriented semantic communication (ToSC) emerges as an innovative approach in the 6G landscape, characterized by the transmission of only vital information that is directly pertinent to a specific task. While ToSC offers an efficient mode of communication, it concurrently raises concerns regarding privacy, as sophisticated adversaries might possess the capability to reconstruct the original data from the transmitted features. This paper provides an in-depth analysis of privacy-preserving strategies specifically designed for ToSC relying on deep neural network-based joint source and channel coding (DeepJSCC). Our study encompasses a detailed comparative assessment of trustworthy feature perturbation methods such as differential privacy (DP) and encryption, alongside intrinsic security incorporation approaches like adversarial learning to train the JSCC and learning-based vector quantization (LBVQ). Our comparative analysis underscores the integration of advanced explainable learning algorithms into communication systems, positing a new benchmark for privacy standards in the forthcoming 6G era.
Ergodic property of random diffusivity system with trapping events
Creators: name: Wang, Xudong
name: Chen, Yao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Brownian yet non-Gaussian phenomenon has recently been observed in many biological and active matter systems. The main idea of explaining this phenomenon is to introduce a random diffusivity for particles moving in inhomogeneous environment. This paper considers a Langevin system containing a random diffusivity and an $α$-stable subordinator with $α<1$. This model describes the particle's motion in complex media where both the long trapping events and random diffusivity exist. We derive the general expressions of ensemble- and time-averaged mean-squared displacements which only contain the values of the inverse subordinator and diffusivity. Further taking specific time-dependent diffusivity, we obtain the analytic expressions of ergodicity breaking parameter and probability density function of the time-averaged mean-squared displacement. The results imply the nonergodicity of the random diffusivity model for any kind of diffusivity, including the critical case where the model presenting normal diffusion.
description: 11 pages, 3 figures, 1 table
Quark-Model Identification of Baryon Ground and Resonant States
Creators: name: Melde, T.
name: Plessas, W.
name: Sengl, B.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We present a new classification scheme of baryon ground states and resonances into SU(3) flavor multiplets. The scheme is worked out along a covariant formalism with relativistic constituent quark models and it relies on detailed investigations of the baryon spectra, the spin-flavor structure of the baryon eigenstates, the behaviour of their probability density distributions as well as covariant predictions for mesonic decay widths. The results are found to be quite independent of the specific types of relativistic constituent quark models employed. It turns out that a consistent classification requires to include also resonances that are presently reported from experiment with only two-star status.
description: 24 pages, 20 Figs
Competition of multiband superconducting and magnetic order in ErNi2B2C observed by Andreev reflection
Creators: name: Bobrov, N. L.
name: Chernobay, V. N.
name: Naidyuk, Yu. G.
name: Tyutrina, L. V.
name: Naugle, D. G.
name: Rathnayaka, K. D. D.
name: Bud`ko, S. L.
name: Canfield, P. C.
name: Yanson, I. K.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: Point contacts (PC) Andreev reflection dV/dI spectra for the antiferromagnetic (T_N =6K) superconductor (Tc=11K) ErNi2B2C have been measured for the two main crystallographic directions. Observed retention of the Andreev reflection minima in dV/dI up to Tc directly points to unusual superconducting order parameter (OP) vanishing at Tc. Temperature dependence of OP was obtained from dV/dI using recent theory of Andreev reflection including pair-breaking effect. For the first time existence of a two superconducting OPs in ErNi2B2C is shown. A distinct decrease of both OPs as temperature is lowered below T_N is observed.
description: 5 pages, 5 figs, to be published in Europhys. Lett
Asymptotic shape for the contact process in random environment
Creators: name: Garet, Olivier
name: Marchand, Régine
Publisher: name: arXiv
Year: 2009
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: The aim of this article is to prove asymptotic shape theorems for the contact process in stationary random environment. These theorems generalize known results for the classical contact process. In particular, if H_t denotes the set of already occupied sites at time t, we show that for almost every environment, when the contact process survives, the set H_t/t almost surely converges to a compact set that only depends on the law of the environment. To this aim, we prove a new almost subadditive ergodic theorem.
description: Published in at http://dx.doi.org/10.1214/11-AAP796 the Annals of Applied Probability (http://www.imstat.org/aap/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Equivalent topological invariants of topological insulators
Creators: name: Wang, Zhong
name: Qi, Xiao-Liang
name: Zhang, Shou-Cheng
Publisher: name: arXiv
Year: 2009
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A time-reversal invariant topological insulator can be generally defined by the effective topological field theory with a quantized θcoefficient, which can only take values of 0 or π. This theory is generally valid for an arbitrarily interacting system and the quantization of the θinvariant can be directly measured experimentally. Reduced to the case of a non-interacting system, the θinvariant can be expressed as an integral over the entire three dimensional Brillouin zone. Alternatively, non-interacting insulators can be classified by topological invariants defined over discrete time-reversal invariant momenta. In this paper, we show the complete equivalence between the integral and the discrete invariants of the topological insulator.
description: Published version. Typos corrected
Additional file 1 of Role of CD8+ T cell exhaustion in the progression and prognosis of acute respiratory distress syndrome induced by sepsis: a prospective observational study
Creators: name: Yan, Lei
name: Chen, Yumei
name: Han, Yi
name: Tong, Chaoyang
Publisher: name: figshare
Year: 2022
Subjects: subject: Immunology
subject: FOS: Clinical medicine

description: Additional file 1: Supplemental Fig. 1. Cumulative incidence for secondary infection. a and b Patients with a lower percentage of lymphocytes (< 8.75) and CD8+ T cells (< 6.47) were more likely to develop secondary infection. c and d Patients with lower percentages of PD-1 + CD8+ T cells (< 5.9) and Tim-3+ CD8+ T cells (< 16.55) had a higher probability of secondary infections.
ARGO: Modeling Heterogeneity in E-commerce Recommendation
Creators: name: Wu, Daqing
name: Luo, Xiao
name: Ma, Zeyu
name: Chen, Chong
name: Deng, Minghua
name: Ma, Jinwen
Publisher: name: arXiv
Year: 2021
Subjects: subject: Information Retrieval (cs.IR)
subject: FOS: Computer and information sciences

description: Nowadays, E-commerce is increasingly integrated into our daily lives. Meanwhile, shopping process has also changed incrementally from one behavior (purchase) to multiple behaviors (such as view, carting and purchase). Therefore, utilizing interaction data of auxiliary behavior data draws a lot of attention in the E-commerce recommender systems. However, all existing models ignore two kinds of intrinsic heterogeneity which are helpful to capture the difference of user preferences and the difference of item attributes. First (intra-heterogeneity), each user has multiple social identities with otherness, and these different identities can result in quite different interaction preferences. Second (inter-heterogeneity), each item can transfer an item-specific percentage of score from low-level behavior to high-level behavior for the gradual relationship among multiple behaviors. Thus, the lack of consideration of these heterogeneities damages recommendation rank performance. To model the above heterogeneities, we propose a novel method named intra- and inter-heterogeneity recommendation model (ARGO). Specifically, we embed each user into multiple vectors representing the user's identities, and the maximum of identity scores indicates the interaction preference. Besides, we regard the item-specific transition percentage as trainable transition probability between different behaviors. Extensive experiments on two real-world datasets show that ARGO performs much better than the state-of-the-art in multi-behavior scenarios.
description: Accepted by IEEE International Joint Conference on Neural Networks (IJCNN) 2021. arXiv admin note: text overlap with arXiv:2105.11876
The effect of vitamin A deficiency on some postmortem parameters of avian muscle
Creators: name: Sundeen, Garfield Byron
Publisher: name: University of British Columbia
Year: 2010

description: The effect of the dietary status of vitamin A on carbohydrate metabolism, postmortem isometric tension development and shear resistance of Pectoral is major muscle was studied. Depletion studies, conducted over a five week period, indicated a definite influence of vitamin A deficiency on muscle carbohydrate metabolism. Mild hypovitaminosis A induced an increase in glycogen deposition whereas a severe deficiency led to a reduction of these elevated stores. Vitamin A deficiency did not affect the abi I ity of P. major strips to develop isometric tension postmortem. P. major strips sampled from deficient cockerels generally required longer to reach maximum tension and, in the later stages, developed significantly greater maximum tension than those of controls. The extended times to maximum tension reflected an increased muscle glycogen content. A significant increase in shear value similarly corresponded to the increased myofibrillar contraction noted in the later deficiency stages. Cockerels which had previously received a completely vitamin A deficient ration for five weeks were utilized for the two week repletion study. Though there was a distinct delay in response to the feeding of a vitamin A adequate ration, the muscle glycogen content, isometric tension parameters and shear values of repleted birds were similar to those of controls within the two week period.
Period Ratio Sculpting Near Second-Order Mean-Motion Resonances
Creators: name: Bailey, Nora
name: Gilbert, Gregory
name: Fabrycky, Daniel
Publisher: name: arXiv
Year: 2021
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: FOS: Physical sciences

description: Second-order mean-motion resonances lead to an interesting phenomenon in the sculpting of the period ratio distribution due to their shape and width in period-ratio/eccentricity space. As the osculating periods librate in resonance, the time-averaged period ratio approaches the exact commensurability. The width of second-order resonances increases with increasing eccentricity, and thus more eccentric systems have a stronger peak at commensurability when averaged over sufficient time. The libration period is short enough that this time-averaging behavior is expected to appear on the timescale of the Kepler mission. Using N-body integrations of simulated planet pairs near the 5:3 and 3:1 mean-motion resonances, we investigate the eccentricity distribution consistent with the planet pairs observed by Kepler. This analysis, an approach independent from previous studies, shows no statistically significant peak at the 3:1 resonance and a small peak at the 5:3 resonance, placing an upper limit on the Rayleigh scale parameter, $σ$, of the eccentricity of the observed Kepler planets at $σ=0.245$ (3:1) and $σ=0.095$ (5:3) at 95% confidence, consistent with previous results from other methods.
description: Accepted for publication in AJ; 28 pages, 24 figures, 4 tables
Creep motion of a granular pile induced by thermal cycling
Creators: name: Divoux, Thibaut
name: Gayvallet, Hervé
name: Géminard, Jean-Christophe
Publisher: name: arXiv
Year: 2008
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We report a time-resolved study of the dynamics associated with the slow compaction of a granular column submitted to thermal cycles. The column height displays a complex behavior: for a large amplitude of the temperature cycles, the granular column settles continuously, experiencing a small settling at each cycle; By contrast, for small-enough amplitude, the column exhibits a discontinuous and intermittent activity: successive collapses are separated by quiescent periods whose duration is exponentially distributed. We then discuss potential mechanisms which would account for both the compaction and the transition at finite amplitude.
description: 4 pages, 5 figures, accepted for publication in Physical Review Letters (05sep08)
The Bose-Hubbard ground state: extended Bogoliubov and variational methods compared with time-evolving block decimation
Creators: name: Danshita, Ippei
name: Naidon, Pascal
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We determine the ground-state properties of a gas of interacting bosonic atoms in a one-dimensional optical lattice. The system is modelled by the Bose-Hubbard Hamiltonian. We show how to apply the time-evolving block decimation method to systems with periodic boundary conditions, and employ it as a reference to find the ground state of the Bose-Hubbard model. Results are compared with recently proposed approximate methods, such as Hartree-Fock-Bogoliubov (HFB) theories generalised for strong interactions and the variational Bijl-Dingle-Jastrow method. We find that all HFB methods do not bring any improvement to the Bogoliubov theory and therefore provide correct results only in the weakly-interacting limit, where the system is deeply in the superfluid regime. On the other hand, the variational Bijl-Dingle-Jastrow method is applicable for much stronger interactions, but is essentially limited to the superfluid regime as it reproduces the superfluid-Mott insulator transition only qualitatively.
description: 9 pages, 8 figures
Deformed Explicitly Correlated Gaussians
Creators: name: Beutel, Matthew
name: Ahrens, Alexander
name: Huang, Chenhang
name: Suzuki, Yasuyuki
name: Varga, Kalman
Publisher: name: arXiv
Year: 2021
Subjects: subject: Chemical Physics (physics.chem-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Deformed correlated Gaussian basis functions are introduced and their matrix elements are calculated. These basis functions can be used to solve problems with nonspherical potentials. One example of such potential is the dipole self-interaction term in the Pauli-Fierz Hamiltonian. Examples are presented showing the accuracy and necessity of deformed Gaussian basis functions to accurately solve light-matter coupled systems in cavity QED.
How to escape atypical regions in the symmetric binary perceptron: a journey through connected-solutions states
Creators: name: Barbier, Damien
Publisher: name: arXiv
Year: 2024
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We study the binary symmetric perceptron model, and in particular its atypical solutions. While the solution-space of this problem is dominated by isolated configurations, it is also solvable for a certain range of constraint density $α$ and threshold $κ$. We provide in this paper a statistical measure probing sequences of solutions, where two consecutive elements shares a strong overlap. After simplifications, we test its predictions by comparing it to Monte-Carlo simulations. We obtain good agreement and show that connected states with a Markovian correlation profile can fully decorrelate from their initialization only for $κ>κ_{\rm no-mem.\, state}$ ($κ_{\rm no-mem.\, state}\sim \sqrt{0.91\log(N)}$ for $α=0.5$ and $N$ being the dimension of the problem). For $κ<κ_{\rm no-mem.\, state}$, we show that decorrelated sequences still exist but have a non-trivial correlations profile. To study this regime we introduce an $Ansatz$ for the correlations that we label as the nested Markov chain.
Infinite rate mutually catalytic branching in infinitely many colonies: The longtime behavior
Creators: name: Klenke, Achim
name: Mytnik, Leonid
Publisher: name: arXiv
Year: 2009
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics

description: Consider the infinite rate mutually catalytic branching process (IMUB) constructed in [Infinite rate mutually catalytic branching in infinitely many colonies. Construction, characterization and convergence (2008) Preprint] and [Ann. Probab. 38 (2010) 479-497]. For finite initial conditions, we show that only one type survives in the long run if the interaction kernel is recurrent. On the other hand, under a slightly stronger condition than transience, we show that both types can coexist.
description: Published in at http://dx.doi.org/10.1214/10-AOP621 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Transport properties and superconductivity in $Ba_{1-x}M_xFe_2As_2$ (M=La and K) with double FeAs layers
Creators: name: Wu, G.
name: Liu, R. H.
name: Chen, H.
name: Yan, Y. J.
name: Wu, T.
name: Xie, Y. L.
name: Ying, J. J.
name: Wang, X. F.
name: Fang, D. F.
name: Chen, X. H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We synthesized the samples $Ba_{1-x}M_xFe_2As_2$ (M=La and K) with $ThCr_2Si_2$-type structure. These samples were systematically characterized by resistivity, thermoelectic power (TEP) and Hall coefficient ($R_H$). $BaFe_2As_2$ shows an anomaly in resistivity at about 140 K. Substitution of La for Ba leads to a shift of the anomaly to low temperature, but no superconducting transition is observed. Potassium doping leads to suppression of the anomaly in resistivity and induces superconductivity at 38 K as reported by Rotter et al.\cite{rotter}. The Hall coefficient and TEP measurements indicate that the TEP is negative for $BaFe_2As_2$ and La-doped $BaFe_2As_2$, indicating n-type carrier; while potassium doping leads to change of the sign in $R_H$ and TEP. It definitely indicates p-type carrier in superconducting $Ba_{1-x}K_xFe_2As_2$ with double FeAs layers, being in contrast to the case of $LnO_{1-x}F_xFeAs$ with single FeAs layer. A similar superconductivity is also observed in the sample with nominal composition $Ba_{1-x}K_xOFe_2As_2$.
description: 4 pages, 4 figures
Dynamics and statistical mechanics of ultra-cold Bose gases using c-field techniques
Creators: name: Blakie, P. B.
name: Bradley, A. S.
name: Davis, M. J.
name: Ballagh, R. J.
name: Gardiner, C. W.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Other Condensed Matter (cond-mat.other)
subject: Atomic Physics (physics.atom-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We review phase space techniques based on the Wigner representation that provide an approximate description of dilute ultra-cold Bose gases. In this approach the quantum field evolution can be represented using equations of motion of a similar form to the Gross-Pitaevskii equation but with stochastic modifications that include quantum effects in a controlled degree of approximation. These techniques provide a practical quantitative description of both equilibrium and dynamical properties of Bose gas systems. We develop versions of the formalism appropriate at zero temperature, where quantum fluctuations can be important, and at finite temperature where thermal fluctuations dominate. The numerical techniques necessary for implementing the formalism are discussed in detail, together with methods for extracting observables of interest. Numerous applications to a wide range of phenomena are presented.
description: 110 pages, 32 figures. Updated to address referee comments. To appear in Advances in Physics
The Early Expansion of Cluster Cores
Creators: name: Bastian, N.
name: Gieles, M.
name: Goodwin, S. P.
name: Trancho, G.
name: Smith, L. J.
name: Konstantopoulos, I.
name: Efremov, Yu.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The observed properties of young star clusters, such as the core radius and luminosity profile, change rapidly during the early evolution of the clusters. Here we present observations of 6 young clusters in M51 where we derive their sizes using HST imaging and ages using deep Gemini-North spectroscopy. We find evidence for a rapid expansion of the cluster cores during the first 20 Myr of their evolution. We confirm this trend by including data from the literature of both Galactic and extra-galactic embedded and young clusters, and possible mechanisms (rapid gas removal, stellar evolutionary mass-loss, and internal dynamical heating) are discussed. We explore the implications of this result, focussing on the fact that clusters were more concentrated in the past, implying that their stellar densities were much higher and relaxation times correspondingly shorter. Thus, when estimating if a particular cluster is dynamically relaxed, (i.e. when determining if a cluster's mass segregation is due to primordial or dynamical processes), the current relaxation time is only an upper-limit, with the relaxation time likely being significantly shorter in the past.
description: 9 pages, 5 figures, accepted MNRAS
An optimal local approximation algorithm for max-min linear programs
Creators: name: Floréen, Patrik
name: Kaasinen, Joel
name: Kaski, Petteri
name: Suomela, Jukka
Publisher: name: arXiv
Year: 2008
Subjects: subject: Distributed, Parallel, and Cluster Computing (cs.DC)
subject: FOS: Computer and information sciences

description: We present a local algorithm (constant-time distributed algorithm) for approximating max-min LPs. The objective is to maximise $ω$ subject to $Ax \le 1$, $Cx \ge ω1$, and $x \ge 0$ for nonnegative matrices $A$ and $C$. The approximation ratio of our algorithm is the best possible for any local algorithm; there is a matching unconditional lower bound.
description: 16 pages, 3 figures
Continuous Solar Observations from the Ground -- Assessing Duty Cycle from GONG Observations
Creators: name: Jain, Kiran
name: Tripathy, Sushant C.
name: Hill, Frank
name: Pevtsov, Alexei A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Continuous observations play an important role in the studies of solar variability. While such observations can be achieved from space with almost 100% duty cycle, it is difficult to accomplish very high duty cycle from the ground. In this context, we assess the duty cycle that has been achieved from the ground by analyzing the observations of a six station network of identical instruments, Global Oscillation Network Group (GONG). We provide a detailed analysis of the duty cycle using GONG observations spanning over 18 years. We also discuss duty cycle of individual sites and point out various factors that may impact individual site or network duty cycle. The mean duty cycle of the network is 93%, however it reduces by about 5% after all images pass through the stringent quality-control checks. The standard deviations in monthly and yearly duty cycle values are found to be 1.9% and 2.2%, respectively. These results provide a baseline that can be used in the planning of future ground-based networks.
description: Preprint contains 30 pages, 24 figures and 8 tables. It is published on an open access basis under a Creative Commons Attribution (CC BY) licence
On spectral stability of solitary waves of nonlinear Dirac equation on a line
Creators: name: Berkolaiko, Gregory
name: Comech, Andrew
Publisher: name: arXiv
Year: 2009
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences
subject: 35Q41, 35C08, 35B35, 81Q05, 37K45

description: We study the spectral stability of solitary wave solutions to the nonlinear Dirac equation in one dimension. We focus on the Dirac equation with cubic nonlinearity, known as the Soler model in (1+1) dimensions and also as the massive Gross-Neveu model. Presented numerical computations of the spectrum of linearization at a solitary wave show that the solitary waves are spectrally stable. We corroborate our results by finding explicit expressions for several of the eigenfunctions. Some of the analytic results hold for the nonlinear Dirac equation with generic nonlinearity.
description: 20 pages with figures
RESIK observations of He-like Ar X-ray line emission in solar flares
Creators: name: Sylwester, J.
name: Sylwester, B.
name: Phillips, K. J. H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The Ar XVII X-ray line group principally due to transitions 1s2 - 1s2l (l=s, p) near 4 Anstroms was observed in numerous flares by the RESIK bent crystal spectrometer aboard CORONAS-F between 2001 and 2003. The three line features include the Ar XVII w (resonance line), a blend of x and y (intercombination lines), and z (forbidden line), all of which are blended with Ar XVI dielectronic satellites. The ratio G, equal to [I(x+y) + I(z)]/I(w), varies with electron temperature Te mostly because of unresolved dielectronic satellites. With temperatures estimated from GOES X-ray emission, the observed G ratios agree fairly well with those calculated from CHIANTI and other data. With a two-component emission measure, better agreement is achieved. Some S XV and S XVI lines blend with the Ar lines, the effect of which occurs at temperatures greater than 8MK, allowing the S/Ar abundance ratio to be determined. This is found to agree with coronal values. A nonthermal contribution is indicated for some spectra in the repeating-pulse flare of 2003 February 6.
description: Latex file and 3 ps files. Astrophysical Journal Letters (accepted, June 2008)
Critical behavior of loops and biconnected clusters on fractals of dimension d < 2
Creators: name: Das, Dibyendu
name: Dey, Supravat
name: Jacobsen, Jesper Lykke
name: Dhar, Deepak
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: We solve the O(n) model, defined in terms of self- and mutually avoiding loops coexisting with voids, on a 3-simplex fractal lattice, using an exact real space renormalization group technique. As the density of voids is decreased, the model shows a critical point, and for even lower densities of voids, there is a dense phase showing power-law correlations, with critical exponents that depend on n, but are independent of density. At n=-2 on the dilute branch, a trivalent vertex defect acts as a marginal perturbation. We define a model of biconnected clusters which allows for a finite density of such vertices. As n is varied, we get a line of critical points of this generalized model, emanating from the point of marginality in the original loop model. We also study another perturbation of adding local bending rigidity to the loop model, and find that it does not affect the universality class.
description: 14 pages,10 figures
Sparse regular random graphs: Spectral density and eigenvectors
Creators: name: Dumitriu, Ioana
name: Pal, Soumik
Publisher: name: arXiv
Year: 2009
Subjects: subject: Probability (math.PR)
subject: Combinatorics (math.CO)
subject: FOS: Mathematics

description: We examine the empirical distribution of the eigenvalues and the eigenvectors of adjacency matrices of sparse regular random graphs. We find that when the degree sequence of the graph slowly increases to infinity with the number of vertices, the empirical spectral distribution converges to the semicircle law. Moreover, we prove concentration estimates on the number of eigenvalues over progressively smaller intervals. We also show that, with high probability, all the eigenvectors are delocalized.
description: Published in at http://dx.doi.org/10.1214/11-AOP673 the Annals of Probability (http://www.imstat.org/aop/) by the Institute of Mathematical Statistics (http://www.imstat.org)
Van der Waals interactions at surfaces by DFT using Wannier functions
Creators: name: Silvestrelli, Pier Luigi
name: Benyahia, Karima
name: Ancilotto, Sonja Grubisic Francesco
name: Toigo, Flavio
Publisher: name: arXiv
Year: 2008
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The method recently developed to include Van der Waals interactions in the Density Functional Theory by using the Maximally-Localized Wannier functions, is improved and extended to the case of atoms and fragments weakly bonded (physisorbed) to metal and semimetal surfaces, thus opening the way to realistic simulations of surface-physics processes, where Van der Waals interactions play a key role. Successful applications to the case of Ar on graphite and on the Al(100) surface, and of the H2 molecule on Al(100) are presented.
description: submitted to Phys. Rev. Lett
Nowe stanowisko Penthophera morio (Linnaeus, 1767) (Lepidoptera: Erebidae: Lymantriinae) na Górnym Śląsku
Creators: name: Lilla Marcickiewicz
name: Adam Malkiewicz
name: Marcin Kadej
Publisher: name: Zenodo
Year: 2025
Subjects: Penthophera morio, tussock moths, endangered species, red list, faunistics, south Poland

description: New record of Penthophera morio (Linnaeus, 1767) (Lepidoptera: Erebidae: Lymantriinae) from Upper Silesia, Poland.Penthophera morio is recorded contemporarely for the second time from Upper Silesia. The moth observation took place in an urbanized area, heavily transformed by human activity, namely the city of Żory. The moth, was observed as early as April, making it the earliest spring observation of the species. Moreover, our locality is currently the westernmost of Penthophera morio in Poland.
Stability of Coassociative Conical Singularities
Creators: name: Lotay, Jason D.
Publisher: name: arXiv
Year: 2009
Subjects: subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 53C38

description: We study the stability of coassociative 4-folds with conical singularities under perturbations of the ambient G_2 structure by defining an integer invariant of a coassociative cone which we call the stability index. The stability index of a coassociative cone is determined by the spectrum of the curl operator acting on its link. We explicitly calculate the stability index for cones on group orbits. We also describe the stability index for cones fibered by 2-planes over algebraic curves using the degree and genus of the curve and the spectrum of the Laplacian on the link. Finally we apply our results to construct the first known examples of coassociative 4-folds with conical singularities in compact manifolds with G_2 holonomy.
description: 59 pages, v2: significant expansion and revision, thus title changed, but key final result is the same; published version
Stabilizing Randomly Switched Systems
Creators: name: Chatterjee, Debasish
name: Liberzon, Daniel
Publisher: name: arXiv
Year: 2008
Subjects: subject: Optimization and Control (math.OC)
subject: FOS: Mathematics
subject: 93E15

description: This article is concerned with stability analysis and stabilization of randomly switched systems under a class of switching signals. The switching signal is modeled as a jump stochastic (not necessarily Markovian) process independent of the system state; it selects, at each instant of time, the active subsystem from a family of systems. Sufficient conditions for stochastic stability (almost sure, in the mean, and in probability) of the switched system are established when the subsystems do not possess control inputs, and not every subsystem is required to be stable. These conditions are employed to design stabilizing feedback controllers when the subsystems are affine in control. The analysis is carried out with the aid of multiple Lyapunov-like functions, and the analysis results together with universal formulae for feedback stabilization of nonlinear systems constitute our primary tools for control design
description: 22 pages. Submitted
Antiferromagnetic order in the FFLO state
Creators: name: Yanase, Youichi
name: Sigrist, Manfred
Publisher: name: arXiv
Year: 2008
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: We investigate the antiferromagnetic (AF) order in the d-wave superconducting (SC) state at high magnetic fields. A two-dimensional model with on-site repulsion U, inter-site attractive interaction V and antiferromagnetic exchange interaction J is solved using the mean field theory. For finite values of U and J, a first order transition occurs from the normal state to the FFLO state, while the FFLO-BCS phase transition is second order, consistent with the experimental results in CeCoIn_5. Although the BCS-FFLO transition is continuous, the Ne'el temperature of AF order is discontinuous at the phase boundary because the AF order in the FFLO state is induced by the Andreev bound state localized in the zeros of FFLO order parameter, while the AF order hardly occurs in the uniform BCS state. The spatial structure of the magnetic moment is investigated for the commensurate AF state as well as for the incommensurate AF state. The influence of the spin fluctuations is discussed for both states. Since the fluctuations are enhanced in the normal state for incommensurate AF order, this AF order can be confined in the FFLO state. The experimental results in CeCoIn_5 are discussed.
description: Proceedings of LT25 conference (Amsterdam, 2008)
Acoustic wave propagation through a supercooled liquid: A normal mode analysis
Creators: name: Matsuoka, Yuki
name: Mizuno, Hideyuki
name: Yamamoto, Ryoichi
Publisher: name: arXiv
Year: 2009
Subjects: subject: Disordered Systems and Neural Networks (cond-mat.dis-nn)
subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: The mechanism of acoustic wave propagation in supercooled liquids is not yet fully understood since the vibrational dynamics of supercooled liquids are strongly affected by their amorphous inherent structures. In this paper, the acoustic wave propagation in a supercooled model liquid is studied by using normal mode analysis. Due to the highly disordered inherent structure, a single acoustic wave is decomposed into many normal modes in broad frequency range. This causes the rapid decay of the acoustic wave and results in anomalous wavenumber dependency of the dispersion relation and the rate of attenuation.
description: 11 pages, 5 figures (color)
Stellar Disruption and the Quasar Radio Dichotomy
Creators: name: Gopal-Krishna
name: Mangalam, A.
name: Wiita, Paul J.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The origin of the dichotomy of radio loudness among quasars can be explained using recent findings that the mass of the central supermassive black hole (SMBH) in extended radio-loud quasars is systematically a few times that of their counterparts in radio-quiet quasars. This sensitive dependence of radio jet ejection upon SMBH mass probably arises from the blockage of jets by the presence of substantial quantities of gas tidally stripped from stars by the central BH. This disruptive gas, however, will only be available around BHs with masses less than $M_c ~\gtrsim ~10^8\Msun$, for which the tidal disruption radius lies outside the SMBH's event horizon. Consequently, we find that AGN with $M_{BH} > M_c$ can successfully launch jets with a wide range of powers, thus producing radio-loud quasars. The great majority of jets launched by less massive BHs, however, will be truncated in the vicinity of the SMBH due to mass loading from this stellar debris. This scenario also can naturally explain the remarkable dearth of extended radio structures in quasars showing broad absorption line spectra.
description: 5 pages, 1 figure, ApJ 680, L13. To appear in Astrophysical Journal Letters
Determination of the magnetic q vectors in the heavy fermion superconductor Ce3PtIn11
Creators: name: Shioda, Naoki
name: Kumeda, Kazuki
name: Fukazawa, Hideto
name: Ohama, Tetsuo
name: Kohori, Yoh
name: Das, Debarchan
name: Blawat, Joanna
name: Kaczorowski, Dariusz
name: Sugimoto, Koudai
Publisher: name: arXiv
Year: 2021
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: An analysis with transferred hyperfine field has been performed on the spectra of the $^{115}$In nuclear quadrupole resonance experiments of heavy fermion superconductor Ce$_{3}$PtIn$_{11}$ exhibiting co-occurrence of two successive antiferromagnetic orderings ($T_{\rm N1}$ = 2.2 K and $T_{\rm N2}$ = 2.0 K) followed by superconducting transition ($T_{\rm c}$ = 0.32 K). The spectral changes at magnetic transition temperatures $T_{\rm N1}$ and $T_{\rm N2}$ indicate that the Ce(2) site has the dominant magnetic contribution, with a small magnetic moment, but not negligible, at the Ce(1) site. Our analysis using transferred hyperfine field which overcomes the previous simple dipolar model evinces that for $T_{\rm N2} < T < T_{\rm N1 } $, the propagation vectors at the Ce(1) and Ce(2) sublattices are q1 = q2 = (1/2, 1/2, 0 or 1/2), whereas for $T < T_{\rm N2 }$, the propagation vectors are q1 = (1/2,~1/2, 1/6 or 1/3) and q2 = (1/2, 1/2, 1/2 or 0), respectively.
description: 15 pages, 4figures
Quantum Painlevé Equations: from Continuous to Discrete
Creators: name: Nagoya, Hajime
name: Grammaticos, Basil
name: Ramani, Alfred
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Algebra (math.QA)
subject: Classical Analysis and ODEs (math.CA)
subject: Exactly Solvable and Integrable Systems (nlin.SI)
subject: FOS: Mathematics
subject: FOS: Physical sciences

description: We examine quantum extensions of the continuous Painlevé equations, expressed as systems of first-order differential equations for non-commuting objects. We focus on the Painlevé equations II, IV and V. From their auto-Bäcklund transformations we derive the contiguity relations which we interpret as the quantum analogues of the discrete Painlevé equations.
description: Published in SIGMA (Symmetry, Integrability and Geometry: Methods and Applications) at http://www.emis.de/journals/SIGMA/