cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
XMM-Newton observation of V1504 Cyg as a probe for the existence of an evaporated corona
Creators: name: Dobrotka, A.
name: Ness, J. -U.
name: Nucita, A. A.
name: Melicherčík, M.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: AIMS: We present an analysis of an XMM-Newton observation of the dwarf novae V1504 Cyg during the decline from an outburst. Our goal is to search for evidence for an evaporated X-ray corona. Such a corona can be understood as an optically thin geometrically thick disc around a central part of an optically thick geometrically thin disc. METHODS: We study the X-ray spectra using a cooling flow model and the evolution of the amplitude of variability and power density spectra in UV and X-rays. RESULTS: The X-ray (pn) count rate increases from initially around 0.03 cps to 0.17 cps with a harder spectrum and a higher degree of variability. Meanwhile, the OM/UVW1 light curve follows a slow decline with decreasing amplitude of variability. For further study we split the X-ray data into two parts, and analysed them separately. Both parts are described by a cooling flow model, while the first low luminosity part requires an additional power law component suggesting presence of a wind. Spectral fitting revealed a higher temperature during the second brighter part. Timing analysis reveals a potential break frequency at log(f/Hz) = -3.02 during decline towards the quiescence. This detection agrees with optical data from Kepler observations. CONCLUSIONS: The X-ray nature of the break frequency supports the innermost parts of the disc as source of the variability. Moreover, a similar frequency was observed in several other cataclysmic variables and a sandwich model where a geometrically thick corona surrounds the geometrically thin disc is a possible accretion configuration.
description: Accepted for publication in Astronomy and Astrophysics
The Northern Cross Fast Radio Burst project -- III. The FRB-magnetar connection in a sample of nearby galaxies
Creators: name: Pelliciari, Davide
name: Bernardi, Gianni
name: Pilia, Maura
name: Naldi, Giovanni
name: Pupillo, Giuseppe
name: Trudu, Matteo
name: Addis, Antonio
name: Bianchi, Germano
name: Bortolotti, Claudio
name: Dallacasa, Daniele
name: Lulli, Roberto
name: Maccaferri, Andrea
name: Magro, Alessio
name: Mattana, Andrea
name: Perini, Federico
name: Roma, Mauro
name: Schiaffino, Marco
name: Setti, Giancarlo
name: Tavani, Marco
name: Verrecchia, Francesco
name: Casentini, Claudio
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Fast radio bursts (FRBs) are millisecond radio transients observed at cosmological distances. The nature of their progenitors is still a matter of debate, although magnetars are invoked by most models. The proposed FRB-magnetar connection was strengthened by the discovery of an FRB-like event from the Galactic magnetar SGR J1935+2154. In this work, we aim to investigate how prevalent magnetars such as SGR J1935+2154 are within FRB progenitors. We carried out an FRB search in a sample of seven nearby (< 12 Mpc) galaxies with the Northern Cross radio telescope for a total of 692 h. We detected one 1.8 ms burst in the direction of M101 with a fluence of $58 \pm 5$ Jy ms. Its dispersion measure of 303 pc cm$^{-3}$ places it most-likely beyond M101. Considering that no significant detection comes indisputably from the selected galaxies, we place a 38 yr$^{-1}$ upper limit on the total burst rate (i.e. including the whole sample) at the 95\% confidence level. This upper limit constrains the event rate per magnetar $λ_{\rm mag} < 0.42$ magnetar$^{-1}$ yr$^{-1}$ or, if combined with literature observations of a similar sample of nearby galaxies, it yields a joint constraint of $λ_{\rm mag} < 0.25$ magnetar$^{-1}$ yr$^{-1}$. We also provide the first constraints on the expected rate of FRBs hypothetically originating from ultraluminous X-ray (ULX) sources, since some of the galaxies observed during our observational campaign host confirmed ULXs. We obtain $< 13$ yr$^{-1}$ per ULX for the total sample of galaxies observed. Our results indicate that bursts with energies $E>10^{34}$ erg from magnetars like SGR J1935+2154 appear more rarely compared to previous observations and further disfavour them as unique progenitors for the cosmological FRB population, leaving more space open to the contribution from a population of more exotic magnetars, not born via core-collapsed supernovae.
description: 9 pages, 4 figures, published in A&A
Collatz-type problems with multiple divisors
Creators: name: Gunn, Keira
Publisher: name: University of British Columbia
Year: 2009

description: The Collatz Conjecture hypothesizes that if a sequence of integers beginning with any positive integer t₀ is recursively defined so that t_j₊₁ = (t_j)/2 when t_j is even and t_j₊₁ = 3(t_j)+1 when t_j is odd, then there will be some j in the set of natural numbers such that t_j = 1. I propose a similar family of problems (which I call systems) involving a set of prime divisors {p₁,...,p_k} and a multiplier m, where the sequence is recursively defined so that t_j₊₁ = (t_j)/(p₁) if t_j is divisible by p₁, t_(j₊₁) = (t_j)/(p₂) if t_j is divisible by p₂ but not p₁, t_(j+1) = (t_j)/(p₃) if t_j is divisible by p₃ but not p₁ or p₂ etc., and if t_j is not divisible by any of the primes, then t_(j₊₁) = m(t_j)₊₁. Assuming the residues of the terms of these sequences behave randomly modulo p₁...p_k, I propose a multiplicative expectation and data to suggest that this is a reasonable model for these systems. If the expectation is less than 1, as in the case of the Collatz problem, then I hypothesize that any sequence will eventually result in some finite cycle. As well, if my model for these systems is accurate, then I prove that the inclusion of an increasing prime q to a fixed set of prime divisors will result in an effect that gradually diminishes for the multiplicative expectation of the system.
The GeMS/GSAOI Galactic Globular Cluster Survey (G4CS) II: Characterization of 47 Tuc with Bayesian Statistics
Creators: name: Simunovic, Mirko
name: Puzia, Thomas H.
name: Miller, Bryan
name: Carrasco, Eleazar R.
name: Dotter, Aaron
name: Cassisi, Santi
name: Monty, Stephanie
name: Stetson, Peter
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: We present a photometric analysis of globular cluster 47 Tuc (NGC\,104), using near-IR imaging data from the GeMS/GSAOI Galactic Globular Cluster Survey (G4CS) which is in operation at Gemini-South telescope.~Our survey is designed to obtain AO-assisted deep imaging with near diffraction-limited spatial resolution of the central fields of Milky Way globular clusters.~The G4CS near-IR photometry was combined with an optical photometry catalog obtained from Hubble Space Telescope survey data to produce a high-quality color-magnitude diagram that reaches down to K$_s\approx$ 21 Vega mag.~We used the software suite BASE-9, which uses an adaptive Metropolis sampling algorithm to perform a Markov chain Monte Carlo (MCMC) Bayesian analysis, and obtained probability distributions and precise estimates for the age, distance and extinction cluster parameters.~Our best estimate for the age of 47 Tuc is 12.42$^{+0.05}_{-0.05}$ $\pm$ 0.08 Gyr, and our true distance modulus estimate is (m$-$M)$_0$=13.250$^{+0.003}_{-0.003}$ $\pm$ 0.028 mag, in tight agreement with previous studies using Gaia DR2 parallax and detached eclipsing binaries.
description: 25 pages, 15 figures. Accepted for publication in The Astrophysical Journal
Multi-tier Network Performance Analysis using a Shotgun Cellular System
Creators: name: Madhusudhanan, Prasanna
name: Restrepo, Juan G.
name: Youjian
name: Liu
name: Brown, Timothy X
name: Baker, Kenneth R.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: This paper studies the carrier-to-interference ratio (CIR) and carrier-to-interference-plus-noise ratio (CINR) performance at the mobile station (MS) within a multi-tier network composed of M tiers of wireless networks, with each tier modeled as the homogeneous n-dimensional (n-D, n=1,2, and 3) shotgun cellular system, where the base station (BS) distribution is given by the homogeneous Poisson point process in n-D. The CIR and CINR at the MS in a single tier network are thoroughly analyzed to simplify the analysis of the multi-tier network. For the multi-tier network with given system parameters, the following are the main results of this paper: (1) semi-analytical expressions for the tail probabilities of CIR and CINR; (2) a closed form expression for the tail probability of CIR in the range [1,Infinity); (3) a closed form expression for the tail probability of an approximation to CIR in the entire range [0,Infinity); (4) a lookup table based approach for obtaining the tail probability of CINR, and (5) the study of the effect of shadow fading and BSs with ideal sectorized antennas on the CIR and CINR. Based on these results, it is shown that, in a practical cellular system, the installation of additional wireless networks (microcells, picocells and femtocells) with low power BSs over the already existing macrocell network will always improve the CINR performance at the MS.
description: 6 pages, 3 figures, accepted at IEEE Globecom 2011
High-velocity CP2 stars in the Galactic halo
Creators: name: Faltová, Nikola
name: Prišegen, Michal
name: Bernhard, Klaus
name: Hümmerich, Stefan
name: Paunzen, Ernst
Publisher: name: arXiv
Year: 2023
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Context. The second subclass of chemically peculiar stars, the CP2 stars, are early-type stars exhibiting anomalous abundances with variable line strengths possibly also accompanied by photometric variability that typically belong to the Galactic disk. However, a small fraction of these objects were recently found to be located far from the Galactic plane and are thought to belong to the Galactic halo, which is unexpected for this class of objects. Aims. Our study investigates the halo membership of the proposed halo CP2 star candidates based on their velocities and Galactic orbits, to determine their points of origin. In addition, we searched for further halo CP2 star candidates using an as-yet-unpublished sample of CP stars. Methods. Our analysis relied on the astrometry from the early third \textit{Gaia} data release and radial velocities based on the spectroscopy from LAMOST and SDSS, which was also employed in spectral classification. The light variability of the confirmed CP2 stars in our sample was analyzed using data from the ZTF and ATLAS surveys. Results. After filtering our initial sample using kinematic and spectroscopic criteria, we identified six CP2 stars with kinematical properties consistent with a halo membership. The orbits of these stars are in agreement with an origin in the Galactic disk where they were probably ejected through dynamical interactions or in the binary supernova scenario, making them the first runaway CP2 stars known.
description: 13 pages, 11 figures, accepted for publication in A&A
The influence of magnetic field geometry on magnetars X-ray spectra
Creators: name: Viganò, D.
name: Parkins, N.
name: Zane, S.
name: Turolla, R.
name: Pons, J. A.
name: Miralles, J. A.
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Nowadays, the analysis of the X-ray spectra of magnetically powered neutron stars or magnetars is one of the most valuable tools to gain insight into the physical processes occurring in their interiors and magnetospheres. In particular, the magnetospheric plasma leaves a strong imprint on the observed X-ray spectrum by means of Compton up-scattering of the thermal radiation coming from the star surface. Motivated by the increased quality of the observational data, much theoretical work has been devoted to develop Monte Carlo (MC) codes that incorporate the effects of resonant Compton scattering in the modeling of radiative transfer of photons through the magnetosphere. The two key ingredients in this simulations are the kinetic plasma properties and the magnetic field (MF) configuration. The MF geometry is expected to be complex, but up to now only mathematically simple solutions (self-similar solutions) have been employed. In this work, we discuss the effects of new, more realistic, MF geometries on synthetic spectra. We use new force-free solutions in a previously developed MC code to assess the influence of MF geometry on the emerging spectra. Our main result is that the shape of the final spectrum is mostly sensitive to uncertain parameters of the magnetospheric plasma, but the MF geometry plays an important role on the angle-dependence of the spectra.
description: 6 pages, 4 figures To appear in Proceedings of II Iberian Nuclear Astrophysics Meeting held in Salamanca, September 22-23, 2011
Universal phonon softening in the pseudogap state of Tl$_2$Ba$_2$Ca$_{n-1}$Cu$_n$O$_{2n+4+δ}$
Creators: name: Hu, Jia-Wei
name: Zhang, Kai
name: Ma, Yong-Chang
name: Wang, Nan-Lin
name: Struzhkin, Viktor V.
name: Goncharov, Alexander F.
name: Lin, Hai-Qing
name: Chen, Xiao-Jia
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: Exploring the origin of the pseudogap is important for the understanding of superconductivity in cuprates. Here we report a systematical experimental study on the phonon vibrational properties of Tl$_2$Ba$_2$Ca$_{n-1}$Cu$_n$O$_{2n+4+δ}$ ($n$=1,2,3) single crystals based on the Raman scattering measurements over the temperature range from 10 to 300 K. The temperature evolution of the frequency and linewidth of the observed phonon modes in each member of this family does not follow the expected self-energy effect when entering the superconducting state. Instead, these phonon modes exhibit a universal softening behavior below the temperature around 150 K, which is higher above the superconducting transition. From the comparison with the existing experimental data for various orders, we find that the observed starting temperature for the phonon softening corresponds to the onset opening temperature of the pseudogap. This finding indicates a large lattice effect in the pseudogap state and the non-negligible spin-phonon coupling for such a phonon softening.
description: 12 pages, 6 figures
Principal Component Analysis of Galaxy Clustering in Hyperspace of Galaxy Properties
Creators: name: Zhou, Shuren
name: Zhang, Pengjie
name: Chen, Ziyang
Publisher: name: arXiv
Year: 2023
Subjects: subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Ongoing and upcoming galaxy surveys are providing precision measurements of galaxy clustering. However a major obstacle in its cosmological application is the stochasticity in the galaxy bias. We explore whether the principal component analysis (PCA) of galaxy correlation matrix in hyperspace of galaxy properties (e.g. magnitude and color) can reveal further information on mitigating this issue. Based on the hydrodynamic simulation TNG300-1, we analyze the cross power spectrum matrix of galaxies in the magnitude and color space of multiple photometric bands. (1) We find that the first principal component $E_i^{(1)}$ is an excellent proxy of the galaxy deterministic bias $b_{D}$, in that $E_i^{(1)}=\sqrt{P_{mm}/λ(1)}b_{D,i}$. Here $i$ denotes the $i$-th galaxy sub-sample. $λ^{(1)}$ is the largest eigenvalue and $P_{mm}$ is the matter power spectrum. We verify that this relation holds for all the galaxy samples investigated, down to $k\sim 2h/$Mpc. Since $E_i^{(1)}$ is a direct observable, we can utilize it to design a linear weighting scheme to suppress the stochasticity in the galaxy-matter relation. For an LSST-like magnitude limit galaxy sample, the stochasticity $\mathcal{S}\equiv 1-r^2$ can be suppressed by a factor of $\ga 2$ at $k=1h/$Mpc. This reduces the stochasticity-induced systematic error in the matter power spectrum reconstruction combining galaxy clustering and galaxy-galaxy lensing from $\sim 12\%$ to $\sim 5\%$ at $k=1h/$Mpc. (2) We also find that $\mathcal{S}$ increases monotonically with $f_λ$ and $f_{λ^2}$. $f_{λ,λ^2}$ quantify the fractional contribution of other eigenmodes to the galaxy clustering and are direct observables. Therefore the two provide extra information on mitigating galaxy stochasticity.
Touch of gas: an ecological enquiry into the effects of the gas processing industry on a community in northwest central Alberta
Creators: name: Edwards, Felicity Nan
Publisher: name: University of Calgary
Year: 1977
Subjects: subject: HC 117 A32 W53 1977 Microfiche
subject: Whitecourt, Alta. - Economic conditions
subject: Whitecourt, Alta. - Social conditions
subject: Gas, Natural - Alberta

description: Bibliography: p. 136-145.
The properties of small magnetic flux ropes inside the solar wind come from coronal holes, active regions, and quiet Sun
Creators: name: Zhai, Changhao
name: Fu, Hui
name: Si, Jiachen
name: Huang, Zhenghua
name: Xia, Lidong
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Space Physics (physics.space-ph)
subject: FOS: Physical sciences

description: The origination and generation mechanisms of small magnetic flux ropes (SFRs), which are important structures in solar wind, are not clearly known. In present study, 1993 SFRs immersed in coronal holes, active regions, and quiet Sun solar wind are analyzed and compared. We find that the properties of SFRs immersed in three types of solar wind are signicantly different. The SFRs are further classifed into hot-SFRs, cold-SFRs, and normal-SFRs, according to whether the O7+/O6+ is 30% elevated or dropped inside SFRs as compared with background solar wind. Our studies show that the parameters of normal-SFRs are similar to background in all three types of solar wind. The properties of hot-SFRs and cold-SFRs seem to be lying in two extremes. Statistically, the hot-SFRs (cold-SFRs) are associated with longer (shorter) duration, lower (higher) speeds and proton temperatures, higher (lower) charge states, helium abundance, and FIP bias as compared with normal-SFRs and background solar wind. The anti-correlations between speed and O7+/O6+ inside hot-SFRs (normal-SFRs) are different from (similar to) those in background solar wind. Most of hot-SFRs and cold-SFRs should come from the Sun. Hot-SFRs may come from streamers associated with plasma blobs and/or small-scale activities on the Sun. Cold-SFRs may be accompanied by small-scale eruptions with lower-temperature materials. Both hot-SFRs and cold-SFRs could also be formed by magnetic erosions of ICMEs that do not contain or contain cold-filament materials. The characteristics of normal-SFRs can be explained reasonably by the two originations, from the Sun and generated in the heliosphere both.
description: 19 pages, 5 figures
Applications of topology in computer algorithms
Creators: name: Telgarsky, Rastislav
Publisher: name: arXiv
Year: 2012
Subjects: subject: Numerical Analysis (math.NA)
subject: Computers and Society (cs.CY)
subject: Geometric Topology (math.GT)
subject: FOS: Mathematics
subject: FOS: Computer and information sciences
subject: G.1.10; G.2.3
subject: 00A71, 65D17, 65D18, 68U10

description: The aim of this paper is to discuss some applications of general topology in computer algorithms including modeling and simulation, and also in computer graphics and image processing. While the progress in these areas heavily depends on advances in computing hardware, the major intellectual achievements are the algorithms. The applications of general topology in other branches of mathematics are not discussed, since they are not applications of mathematics outside of mathematics.
description: This paper is based on the invited lecture at International Conference on Topology and Applications held in August 23--27, 1999, at Kanagawa University in Yokohama, Japan
Progenitor constraint with circumstellar material for the magnetar-hosting supernova remnant RCW 103
Creators: name: Narita, Takuto
name: Uchida, Hiroyuki
name: Yoshida, Takashi
name: Tanaka, Takaaki
name: Tsuru, Takeshi Go
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Stellar winds blown out from massive stars ($\gtrsim 10M_{\odot}$) contain precious information on the progenitor itself, and in this context, the most important elements are carbon (C), nitrogen (N), and oxygen (O), which are produced by the CNO cycle in the H-burning layer. Although their X-ray fluorescence lines are expected to be detected in swept-up shock-heated circumstellar materials (CSMs) in supernova remnants (SNRs), particularly those of C and N have been difficult to detect so far. Here, we present a high-resolution spectroscopy of a young magnetar-hosting SNR RCW~103 with the Reflection Grating Spectrometer (RGS) onboard XMM-Newton and report on the detection of \ion{N}{7} Ly$α$ (0.50~keV) line for the first time. By comparing the obtained abundance ratio of N to O (N/O$=3.8 \pm{0.1}$) with various stellar evolution models, we show that the progenitor of RCW~103 is likely to have a low-mass (10--12~$M_{\odot}$) and medium-rotation velocities ($\lesssim 100~\rm{km~s^{-1}}$). The results also rule out the possibility of dynamo effects in massive ($\geq35~M_{\odot}$) stars as a formation mechanism of the associated magnetar 1E~161348$-$5055. Our method is useful for estimating various progenitor parameters for future missions with microcalorimeters such as XRISM and Athena.
description: Accepted for publication in ApJ. 11 pages, 8 figures
Identification of field dwarfs and giants in RAVE
Creators: name: Bilir, S.
name: Karaali, S.
name: Ak, S.
name: Onal, O.
name: Coskunoglu, B.
name: Seabroke, G. M.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: The second RAdial Velocity Experiment (RAVE) Data Release (DR2) derives log g values but we present a simpler and cleaner method of identifying dwarfs and giants using only magnitudes, which does not require spectroscopic analysis. We confirm the Bilir et al. (2006) procedure which estimates the number of dwarfs and giants via their positions in the J-V two magnitude diagram by applying it to RAVE DR2. It is effective in estimating the number of dwarfs and giants at J-H>0.4 compared to RAVE's log g values. For J-H<=0.4, where dwarfs and subgiants show a continuous transition in the J magnitude histogram, we used the Besancon Galaxy model predictions to statistically isolate giants. The percentages of giants for red stars and for the whole sample are 85% and 34%, respectively. If we add the subgiants, the percentage of evolved stars for the whole sample raises to 59%. For the first time in the literature, we analysed the effect of CHISQ on RAVE's log g values (CHISQ is the penalised chi^2 from RAVE's technique of finding an optimal match between the observed spectrum and synthetic spectra to derive stellar parameters). Neither the CHISQ values nor the signal-to-noise ratio bias RAVE log g values. Therefore the method of identifying dwarfs and giants via the two magnitude diagram has been verified against an unbiased dataset.
description: 23 pages, including 9 figures and 5 tables, accepted for publication in MNRAS
Recreational activities and perceptions in the Kananaskis region, Alberta
Creators: name: Erdman, Kenneth Richard
Publisher: name: University of Calgary
Year: 1978
Subjects: subject: GV 191.46 A4 E72 1978 Microfiche
subject: Recreation areas - Planning - Alberta - Kananaskis Valley
subject: Environmental Psychology
subject: Recreational surveys - Alberta - Kananaskis Valley

description: Bibliography: p. 110-117.
Hairy Black Holes and Null Circular Geodesics
Creators: name: Hod, Shahar
Publisher: name: arXiv
Year: 2011
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Einstein-matter theories in which hairy black-hole configurations have been found are studied. We prove that the nontrivial behavior of the hair must extend beyond the null circular orbit (the photonsphere) of the corresponding spacetime. We further conjecture that the region above the photonsphere contains at least 50% of the total hair's mass. We support this conjecture with analytical and numerical results.
description: 5 pages
Numerical simulations of black hole-neutron star mergers in scalar-tensor gravity
Creators: name: Ma, Sizheng
name: Varma, Vijay
name: Stein, Leo C.
name: Foucart, Francois
name: Duez, Matthew D.
name: Kidder, Lawrence E.
name: Pfeiffer, Harald P.
name: Scheel, Mark A.
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We present a numerical-relativity simulation of a black hole - neutron star merger in scalar-tensor (ST) gravity with binary parameters consistent with the gravitational wave event GW200115. In this exploratory simulation, we consider the Damour-Esposito-Farese extension to Brans-Dicke theory, and maximize the effect of spontaneous scalarization by choosing a soft equation of state and ST theory parameters at the edge of known constraints. We extrapolate the gravitational waves, including tensor and scalar (breathing) modes, to future null-infinity. The numerical waveforms undergo ~ 22 wave cycles before the merger, and are in good agreement with predictions from post-Newtonian theory during the inspiral. We find the ST system evolves faster than its general-relativity (GR) counterpart due to dipole radiation, merging a full gravitational-wave cycle before the GR counterpart. This enables easy differentiation between the ST waveforms and GR in the context of parameter estimation. However, we find that dipole radiation's effect may be partially degenerate with the NS tidal deformability during the late inspiral stage, and a full Bayesian analysis is necessary to fully understand the degeneracies between ST and binary parameters in GR.
Sensing and decision-making in random search
Creators: name: Hein, Andrew M.
name: McKinley, Scott A.
Publisher: name: arXiv
Year: 2012
Subjects: subject: Populations and Evolution (q-bio.PE)
subject: Probability (math.PR)
subject: FOS: Biological sciences
subject: FOS: Mathematics
subject: 92D50, 60K40

description: While microscopic organisms can use gradient-based search to locate resources, this strategy can be poorly suited to the sensory signals available to macroscopic organisms. We propose a framework that models search-decision making in cases where sensory signals are infrequent, subject to large fluctuations, and contain little directional information. Our approach simultaneously models an organism's intrinsic movement behavior (e.g. Levy walk) while allowing this behavior to be adjusted based on sensory data. We find that including even a simple model for signal response can dominate other features of random search and greatly improve search performance. In particular, we show that a lack of signal is not a lack of information. Searchers that receive no signal can quickly abandon target-poor regions. Such phenomena naturally give rise to the area-restricted search behavior exhibited by many searching organisms.
The hyperfine properties of a hydrogenated Fe/V superlattice
Creators: name: Elzain, M.
name: Al-Barwani, M.
name: Gismelseed, A.
name: Al-Rawas, A.
name: Yousif, A.
name: Widatallah, H.
name: Bouziane, K.
name: Al-Omari, I.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: : We study the effect of hydrogen on the electronic, magnetic and hyperfine structures of an iron-vanadium superlattice consisting of three Fe monolayers and nine V monolayers. The contact charge density (ρ), the contact hyperfine field (Bhf) and the electronic field gradient (EFG) at the Fe sites for different H locations and H fillings are calculated using the first principle full-potential linear-augmented-plane-wave (FP-LAPW) method . It is found that sizeable changes in the hyperfine properties are obtained only when H is in the interface region.
description: 6 pages, 2 figures, 3 tables, ICAME 2011 conference (Kobe, Japan)
ОСОБЕННОСТИ ФОРМИРОВАНИЯ У ДЕТЕЙ НАВЫКОВ ИННОВАЦИОННОГО МЫШЛЕНИЯ
Creators: name: Кадирова, Дилдора
name: Бурдина, Зоя
name: Абдурахманова, Дилдора
Publisher: name: Zenodo
Year: 2023

description: Публикация посвящена анализу особенностей формирования навыков инновационного мышления и обучения детей дошкольного возраста в ДОО, с помощью которых можно добиться больших результатов в воспитании и развитии способностей детей.
Directing Euripides' Medea
Creators: name: Anderson, Lois Marjory
Publisher: name: University of British Columbia
Year: 2009

description: This thesis documents the directorial preparation and rehearsal process for the production of Euripides Medea, produced at the TELUS theatre, January 2009, as the thesis requirement for an MFA in Directing from the Theatre Department of the University of British Columbia. Included are a script analysis of the Kenneth McLeish translation of Medea, a rehearsal journal, and an essay examining the role and intervention of the gods in Euripides’ Medea. This production was framed as a re-enactment by the household staff of Jason and Medea. The appendix includes a storyboard script for the household characters written by the director. The bibliography includes sources used by the director for script analysis research. Challenges in staging Medea include the deus ex machina, the child actors and staging the Greek Chorus. An essential question explored in this production is the character of Medea and whether the audience is to consider her as a monster or as a human. This production explored the deus ex machina as an act of grace, signaling that the gods transcend societal codes of justice, and that Euripides offers the image of a complex woman, struggling and stumbling towards the divine.
Microscopic study of the 2/5 fractional quantum Hall edge
Creators: name: Sreejith, G. J.
name: Jolad, Shivakumar
name: Sen, Diptiman
name: Jain, Jainendra K.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Strongly Correlated Electrons (cond-mat.str-el)
subject: FOS: Physical sciences

description: This paper reports on our study of the edge of the 2/5 fractional quantum Hall state, which is more complicated than the edge of the 1/3 state because of the presence of a continuum of quasi-degenerate edge sectors corresponding to different partitions of composite fermions in the lowest two Λ levels. The addition of an electron at the edge is a non-perturbative process and it is not a priori obvious in what manner the added electron distributes itself over these sectors. We show, from a microscopic calculation, that when an electron is added at the edge of the ground state in the [N_1, N_2] sector, where N_1 and N_2 are the numbers of composite fermions in the lowest two Λ levels, the resulting state lies in either [N_1 + 1, N_2] or [N_1, N_2 + 1] sector; adding an electron at the edge is thus equivalent to adding a composite fermion at the edge. The coupling to other sectors of the form [N_1 + 1 + k, N_2 - k], k integer, is negligible in the asymptotically low-energy limit. This study also allows a detailed and substantial comparison with the two-boson model of the 2/5 edge. We compute the spectral weights and find that while the individual spectral weights are complicated and non-universal, their sum is consistent with an effective two-boson description of the 2/5 edge.
description: 11 pages, 7 figures
Sparse logistic regression for RR Lyrae vs binaries classification
Creators: name: Trevisan, Piero
name: Pasquato, Mario
name: Carenini, Gaia
name: Mekhael, Nicolas
name: Braga, Vittorio F.
name: Bono, Giuseppe
name: Abbas, Mohamad
Publisher: name: arXiv
Year: 2023
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: RR Lyrae (RRL) are old, low-mass radially pulsating variable stars in their core helium burning phase. They are popular stellar tracers and primary distance indicators, since they obey to well defined period-luminosity relations in the near-infrared regime. Their photometric identification is not trivial, indeed, RRL samples can be contaminated by eclipsing binaries, especially in large datasets produced by fully automatic pipelines. Interpretable machine-learning approaches for separating eclipsing binaries from RRL are thus needed. Ideally, they should be able to achieve high precision in identifying RRL while generalizing to new data from different instruments. In this paper, we train a simple logistic regression classifier on Catalina Sky Survey (CSS) light curves. It achieves a precision of 87% at 78% recall for the RRL class on unseen CSS light curves. It generalizes on out-of-sample data (ASAS/ASAS-SN light curves) with a precision of 85% at 96% recall. We also considered a L1-regularized version of our classifier, which reaches 90% sparsity in the light-curve features with a limited trade-off in accuracy on our CSS validation set and -- remarkably -- also on the ASAS/ASAS-SN light curve test set. Logistic regression is natively interpretable, and regularization allows us to point out the parts of the light curves that matter the most in classification. We thus achieved both good generalization and full interpretability.
description: To appear on The Astrophysical Journal. 13 pages, 8 figures, 3 tables
Relationship between character and natural environment in selected novels of Thomas Hardy
Creators: name: Evans, Edward John
Publisher: name: University of Calgary
Year: 1973
Subjects: subject: PR 4757 E7 E82 1973 Microfiche
subject: Hardy, Thomas, 1840-1928
subject: Characters and characteristics in literature
subject: Environmental psychology in literature

description: Bibliography: p. 128-135.
Students' accommodation allocation: A Multicriteria Decision Support System
Creators: name: Rasoanaivo, Rôlin Gabriel
name: Zaraté, Pascale
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computers and Society (cs.CY)
subject: FOS: Computer and information sciences

description: The social life of students at university has an impact on their educational success. The allocation of accommodation is part of this aspect. This article presents our proposal to improve students' allocation accommodation. We aim to support university administrative departments for the selection of students for housing. Therefore, we propose a decision support system based on multi-criteria decision support methods. To calculate the weights of the criteria, we use the AHP method. Then, to rank the students, AHP, Weighted Sum Method and PROMETHEE methods are used. The aim is to find the most adequate method to rank the students. The result is achieved because the AHP is able to calculate the weight of criteria and the AHP, SWM and PROMETHEE are able to rank the students.
Studies of Hadronization Mechanisms using Pion Electroproduction in Deep Inelastic Scattering from Nuclei
Creators: name: Brooks, Will
name: Hakobyan, Hayk
name: Peña, Cristian
name: Arratia, Miguel
name: Valdés, Constanza
Publisher: name: arXiv
Year: 2011
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: Atomic nuclei can be used as spatial analyzers of the hadronization process in semi-inclusive deep inelastic scattering. The study of this process using fully-identified final state hadrons began with the HERMES program in the late 1990s, and is now continuing at Jefferson Lab. In the measurement described here, electrons and positive pions were measured from a 5 GeV electron beam incident on targets of liquid deuterium, C, Fe, and Pb using CLAS in Hall B. The broadening of the transverse momentum of positive pions has been studied in detail as a function of multiple kinematic variables, and interpreted in terms of the transport of the struck quark through the nuclear systems. New insights are being obtained into the hadronization process from these studies; and experiments of this type can be relevant for the interpretation of jet quenching and proton-nucleus collisions at RHIC and LHC. These measurements will be extended in the next few years with the approved JLab experiment E12-06-117, and later at a future Electron-Ion Collider.
description: 3 pages, 2 figures; proceedings of the 19th Particles & Nuclei International Conference (PANIC), 2011, with one updated figure
On the linear forms of the Schrodinger equation
Creators: name: Kasri, Y.
name: Bérard, A.
name: Grandati, Y.
name: Chetouani, L.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Generalizing the linearisation procedure used by Dirac and later by Lévy-Leblond, we derive the first-order non-relativistic wave equations for particles of spin 1 and spin 3/2 starting from the Schrodinger equation.
Multi-Scale Feature Fusion using Parallel-Attention Block for COVID-19 Chest X-ray Diagnosis
Creators: name: Qi, Xiao
name: Foran, David J.
name: Nosher, John L.
name: Hacihaliloglu, Ilker
Publisher: name: arXiv
Year: 2023
Subjects: subject: Image and Video Processing (eess.IV)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: FOS: Electrical engineering, electronic engineering, information engineering
subject: FOS: Computer and information sciences

description: Under the global COVID-19 crisis, accurate diagnosis of COVID-19 from Chest X-ray (CXR) images is critical. To reduce intra- and inter-observer variability, during the radiological assessment, computer-aided diagnostic tools have been utilized to supplement medical decision-making and subsequent disease management. Computational methods with high accuracy and robustness are required for rapid triaging of patients and aiding radiologists in the interpretation of the collected data. In this study, we propose a novel multi-feature fusion network using parallel attention blocks to fuse the original CXR images and local-phase feature-enhanced CXR images at multi-scales. We examine our model on various COVID-19 datasets acquired from different organizations to assess the generalization ability. Our experiments demonstrate that our method achieves state-of-art performance and has improved generalization capability, which is crucial for widespread deployment.
description: Accepted for publication at the Journal of Machine Learning for Biomedical Imaging (MELBA) https://melba-journal.org/2023:008
Molecular mechanisms underlying the crosstalk between autophagy and apoptosis
Creators: name: Hou, Ying Chen
Publisher: name: University of British Columbia
Year: 2010

description: Macroautophagy (hereafter referred to as autophagy) is an evolutionary conserved mechanism for the degradation of long-lived proteins and organelles inside lysosomes. Autophagy functions as an adaptive survival response to starvation and other cellular stresses, but recent studies also demonstrated a role for autophagy in cell death. Functional studies indicate that a complex relationship exists between autophagy and apoptosis, the most common form of cell death, but the regulatory mechanisms underlying their interactions are largely unknown. To advance our understanding of the links between these two processes, I conducted a RNAi screen of Drosophila melanogaster cell death-related genes for their requirement in the regulation of starvation-induced autophagy. I discovered that six cell death genes, Dcp-1, hid, Bruce, Buffy, debcl, and p53 as well as Ras/Raf/MAPK signaling pathway components function in autophagy regulation in Drosophila l(2)mbn cells. I used Drosophila genetics to investigate a role for effector caspase Dcp-1 and inhibitor of apoptosis protein Bruce during autophagy in vivo. During Drosophila oogenesis, I found that autophagy is induced at two nutrient status checkpoints, the germarium and mid-oogenesis. Degenerating mid-stage egg chambers in DmAtg1 and DmAtg7 mutants exhibited reduced DNA fragmentation, suggesting autophagy may contribute to cell death during oogenesis. At the two nutrient status checkpoints in the developing ovary, Dcp-1 and Bruce function to regulate both autophagy and starvation-induced cell death, and epistasis analysis showed that Dcp-1 is downstream of Bruce, indicating that Bruce may negatively regulate Dcp-1 activity. In addition, I found that the catalytic activity of Dcp-1 is essential for autophagy regulation, suggesting that Dcp-1 dependent proteolysis may serve as a regulatory mechanism by which Dcp-1 mediates a cellular switch between autophagy and apoptosis. To identify potential substrates of Dcp-1, I employed an immuno-precipitation and mass spectrometry assay, the results of which can be used to generate a working model for how Dcp-1 controls autophagy. In summary, I developed an efficient screening method that resulted in the identification of several cell death-related regulators of autophagy. Further genetic and biochemical analyses of the effector caspase Dcp-1 in autophagy regulation provided new insights into the relationships between autophagy and apoptosis.
On the second-order temperature jump coefficient of a dilute gas
Creators: name: Radtke, Gregg A.
name: Hadjiconstantinou, Nicolas G.
name: Takata, Shigeru
name: Aoki, Kazuo
Publisher: name: arXiv
Year: 2012
Subjects: subject: Fluid Dynamics (physics.flu-dyn)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: We use LVDSMC simulations to calculate the second-order temperature jump coefficient for a dilute gas whose temperature is governed by the Poisson equation with a constant forcing term. Both the hard sphere gas and the BGK model of the Boltzmann equation are considered. Our results show that the temperature jump coefficient is different from the well known linear and steady case where the temperature is governed by the homogeneous heat conduction (Laplace) equation.
Muon puzzle in ultra-high energy EASs according to Yakutsk array and Auger experiment data
Creators: name: Glushkov, A. V.
name: Sabourov, A. V.
name: Ksenofontov, L. T.
name: Lebedev, K. G.
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: The lateral distribution of particles in extensive air showers from cosmic rays with energy above $10^{17}$ eV registered at the Yakutsk complex array was analyzed. Experimentally measured particle densities were compared to the predictions obtained within frameworks of three ultra-high energy hadron interaction models. The cosmic ray mass composition estimated by the readings of surface-based and underground detectors of the array is consistent with results based on the Cherenkov light lateral distribution data. A comparison was made with the results of direct measurement of the muon component performed at the Pierre Auger Observatory. It is demonstrated that the densities of muon flux measured at Yakutsk array are consistent with results of fluorescent light measurements and disagree with results on muons obtained at the Auger array.
description: 14 pages, 6 figures, 2 tables. Accepted for publication in JETP Letters
Determining the Difficulties of Students With Dyslexia via Virtual Reality and Artificial Intelligence: An Exploratory Analysis
Creators: name: Yeguas-Bolívar, Enrique
name: Alcalde-Llergo, José M.
name: Aparicio-Martínez, Pilar
name: Taborri, Juri
name: Zingoni, Andrea
name: Pinzi, Sara
Publisher: name: arXiv
Year: 2024
Subjects: subject: Computers and Society (cs.CY)
subject: Artificial Intelligence (cs.AI)
subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Graphics (cs.GR)
subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: Learning disorders are neurological conditions that affect the brain's ability to interconnect communication areas. Dyslexic students experience problems with reading, memorizing, and exposing concepts; however the magnitude of these can be mitigated through both therapies and the creation of compensatory mechanisms. Several efforts have been made to mitigate these issues, leading to the creation of digital resources for students with specific learning disorders attending primary and secondary education levels. Conversely, a standard approach is still missed in higher education. The VRAIlexia project has been created to tackle this issue by proposing two different tools: a mobile application integrating virtual reality (VR) to collect data quickly and easily, and an artificial intelligencebased software (AI) to analyze the collected data for customizing the supporting methodology for each student. The first one has been created and is being distributed among dyslexic students in Higher Education Institutions, for the conduction of specific psychological and psychometric tests. The second tool applies specific artificial intelligence algorithms to the data gathered via the application and other surveys. These AI techniques have allowed us to identify the most relevant difficulties faced by the students' cohort. Our different models have obtained around 90\% mean accuracy for predicting the support tools and learning strategies.
description: 7 pages, 5 figures, 3 tables, MetroXRAINE 2022 Conference, VRAILEXIA european project
Comment on "Twin symmetry texture of energetically condensed niobium thin films on sapphire substrates (a-plane Al2O3)" [J. Appl. Phys. 110, 033523 (2011)]
Creators: name: Welander, Paul B.
Publisher: name: arXiv
Year: 2011
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: In their recent publication, Zhao et al. [J. Appl. Phys. 110, 033523 (2011)] claim to have found a new three-dimensional relationship for niobium-on-sapphire epitaxy. However, two critical errors were made in the analysis of x-ray diffraction measurements. The crystal structure of sapphire (alpha-Al2O3) was erroneously cited as hexagonal close-packed, and crystallographic orientations of sapphire were misidentified. Correcting these errors, one finds their claim unjustified.
description: 2 pages, 2 figures
The Interorganizational bases of community power: a case study of Banff
Creators: name: Koch, Agnes Bernice
Publisher: name: University of Calgary
Year: 1974
Subjects: subject: HN 110 B34 K6 1974 Microfiche
subject: Community development - Alberta - Banff
subject: Community leadership
subject: Community organization - Law and legislation - Alberta - Banff

description: Bibliography: p. 33-34.