cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Robust two-dimensional superconductivity and vortex system in Bi2Te3/FeTe heterostructures
Creators: name: Liu, Hong-Chao
name: Li, Hui
name: He, Qing Lin
name: Sou, Iam Keong
name: Goh, Swee K.
name: Wang, Jiannong
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The discovery of two-dimensional superconductivity in Bi2Te3/FeTe heterostructure provides a new platform for the search of Majorana fermions in condensed matter systems. Since Majorana fermions are expected to reside at the core of the vortices, a close examination of the vortex dynamics in superconducting interface is of paramount importance. Here, we report the robustness of the interfacial superconductivity and 2D vortex dynamics in four as-grown and aged Bi2Te3/FeTe heterostructure with different Bi2Te3 epilayer thickness (3, 5, 7, 14 nm). After two years' air exposure, superconductivity remains robust even when the thickness of Bi2Te3 epilayer is down to 3 nm. Meanwhile, a new feature at ~13 K is induced in the aged samples, and the high field studies reveal its relevance to superconductivity. The resistance of all as-grown and aged heterostructures, just below the superconducting transition temperature follows the Arrhenius relation, indicating the thermally activated flux flow behavior at the interface of Bi2Te3 and FeTe. Moreover, the activation energy exhibits a logarithmic dependence on the magnetic field, providing a compelling evidence for the 2D vortex dynamics in this novel system. The weak disorder associated with aging-induced Te vacancies is possibly responsible for these observed phenomena.
description: 21 pages, article+supplemental information, published in Scientific Reports
Adams' Cobar Construction Revisited
Creators: name: Rivera, Manuel
Publisher: name: Deutsche Mathematiker-Vereinigung
Year: 2022

description: We give a short and streamlined proof of the following statement recently proven by the author and M. Zeinalian: the cobar construction of the dg coassociative coalgebra of normalized singular chains on a path-connected pointed space is naturally quasi-isomorphic as a dg associative algebra to the singular chains on the based loop space. This extends a classical theorem of F. Adams originally proven for simply connected spaces. Our proof is based on relating the cobar functor to the left adjoint of the homotopy coherent nerve functor.
description: DOCUMENTA MATHEMATICA, Vol 27 (2022), p. 1213-1223
What is a (Geo)Chemical Analysis: A High Level View
Creators: name: Wyborn, Lesley
name: Prent, Alexander
name: Lehnert, Kerstin
name: Klöcking, Marthe
name: Elger, Kirsten
name: ter Maat, Geertje
name: Hezel, Dominik
name: Profeta, Lucy
Publisher: name: Zenodo
Year: 2022
Subjects: Webinar, FAIR, Cheminformatics, Chemical Data

description: This is a flash presentation highlighting working with Geoscience data. It was presented at the “The IUPAC WorldFAIR Chemistry Webinar “What is a chemical? - Handling Chemical Data Across Disciplines”. The event was held on September 22, 2022, 12-1:30 pm EDT. The recording of the full webinar is available here *WorldFAIR “Global cooperation on FAIR data policy and practice” is funded by the EC HORIZON-WIDERA-2021-ERA-01-41 Coordination and Support Action under Grant Agreement No. 101058393.
Categorification of the Elliptic Hall Algebra
Creators: name: Mousaaid, Youssef
name: Savage, Alistair
Publisher: name: Deutsche Mathematiker-Vereinigung
Year: 2022

description: We show that the central charge $k$ reduction of the universal central extension of the elliptic Hall algebra is isomorphic to the trace, or zeroth Hochschild homology, of the quantum Heisenberg category of central charge $k$. As an application, we construct large families of representations of the universal extension of the elliptic Hall algebra.
description: DOCUMENTA MATHEMATICA, Vol 27 (2022), p. 1225-1273
Aspects of the problem of protection of the ischaemic myocardium
Creators: name: P'ing., Lin Shun
Publisher: name: Monash University
Year: 2021

description: This thesis was scanned from the print manuscript for digital preservation and is copyright the author.
 Researchers can access this thesis by asking their local university, institution or public library to
 make a request on their behalf. Monash staff and postgraduate students can use the link in the References field.
Black Hole Mass Estimation: How good is the virial estimate?
Creators: name: Yong, Suk Yee
name: Webster, Rachel L.
name: King, Anthea L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Black hole mass is a key factor in determining how a black hole interacts with its environment. However, the determination of black hole masses at high redshifts depends on secondary mass estimators, which are based on empirical relationships and broad approximations. A dynamical disk wind broad line region (BLR) model of active galactic nuclei (AGN) is built in order to test the impact on the black hole mass calculation due to different BLR geometries and the inclination of the AGN. Monte Carlo simulations of two disk wind models are constructed to recover the virial scale factor, $f$, at various inclination angles. The resulting $f$ values strongly correlate with inclination angle, with large $f$ values associated with small inclination angles (close to face-on) and small $f$ values with large inclination angles (close to edge-on). The $f$ factors are consistent with previously determined $f$ values, found from empirical relationships. Setting $f$ as a constant may introduce a bias into virial black hole mass estimates for a large sample of AGN. However, the extent of the bias depends on the line width characterisation (e.g. full width at half maximum (FWHM) or line dispersion). Masses estimated using $f_{\text{FWHM}}$ tend to biased towards larger masses, but this can be corrected by calibrating for the width or shape of the emission line.
description: Accepted for publication in PASA. 9 pages, 5 figures, 2 table
New neutron-deficient isotopes from $^{78}$Kr fragmentation
Creators: name: Blank, B.
name: Goigoux, T.
name: Ascher, P.
name: Gerbaux, M.
name: Giovinazzo, J.
name: Grevy, S.
name: Nieto, T. Kurtukian
name: Magron, C.
name: Agramunt, J.
name: Algora, A.
name: Guadilla, V.
name: Montaner-Piza, A.
name: Morales, A. I.
name: Orrigo, S. E. A.
name: Rubio, B.
name: Ahn, D. S.
name: Doornenbal, P.
name: Fukuda, N.
name: Inabe, N.
name: Kiss, G.
name: Kubo, T.
name: Kubono, S.
name: Nishimura, S.
name: Phong, V. H.
name: Sakurai, H.
name: Shimizu, Y.
name: Soderstrom, P. -A.
name: Sumikama, T.
name: Suzuki, H.
name: Takeda, H.
name: Wu, J.
name: Fujita, Y.
name: Tanaka, M.
name: Gelletly, W.
name: Aguilera, P.
name: Molina, F.
name: Diel, F.
name: Lubos, D.
name: de Angelis, G.
name: Napoli, D.
name: Borcea, C.
name: Boso, A.
name: Cakirli, R. B.
name: Ganioglu, E.
name: Chiba, J.
name: Nishimura, D.
name: Oikawa, H.
name: Takei, Y.
name: Yagi, S.
name: Wimmer, K.
name: de France, G.
name: Go, S.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: In an experiment with the BigRIPS separator at the RIKEN Nishina Center, the fragmentation of a $^{78}$Kr beam allowed the observation of new neutron-deficient isotopes at the proton drip-line. Clean identification spectra could be produced and $^{63}$Se, $^{67}$Kr, and $^{68}$Kr were identified for the first time. In addition, $^{59}$Ge was also observed. Three of these isotopes, $^{59}$Ge, $^{63}$Se, and $^{67}$Kr, are potential candidates for ground-state two-proton radioactivity. In addition, the isotopes $^{58}$Ge, $^{62}$Se, and $^{66}$Kr were also sought but without success. The present experiment also allowed the determination of production cross sections for some of the most exotic isotopes. These measurements confirm the trend already observed that the empirical parameterization of fragmentation cross sections, EPAX, significantly overestimates experimental cross sections in this mass region.
description: accepted as Rapid Communication in PRC
The VIMOS Ultra Deep Survey: Lyman Alpha Emission and Stellar Populations of Star-Forming Galaxies at 2
Creators: name: Hathi, Nimish P.
name: Fevre, Olivier Le
name: team, the VUDS
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: The extensive ground-based spectroscopy campaign from the VIMOS Ultra-Deep Survey (VUDS), and the deep multi-wavelength photometry in three very well observed extragalactic fields (ECDFS, COSMOS, VVDS), allow us to investigate physical properties of a large sample (~4000 galaxies) of spectroscopically confirmed faint (i_{AB}20A) increases from ~10% at z~2 to ~40% at z~5-6, which is consistent with previous studies that employ higher Lyman alpha EW cut. This increase in the LAE fraction could be, in part, due to a decrease in the dust content of galaxies as redshift increases. When we compare best-fit SED estimated stellar parameters for LAEs and non-LAEs, we find that E(B-V) is smaller for LAEs at all redshifts and the difference in the median E(B-V) between LAEs and non-LAEs increases as redshift increases, from 0.05 at z~2 to 0.1 at z~3.5 to 0.2 at z~5-6. For the luminosities probed here (~L*), we find that star formation rates (SFRs) and stellar masses of galaxies, with and without Lyman alpha in emission, show small differences such that, LAEs have lower SFRs and stellar masses compared to non-LAEs. This result could be a direct consequence of the sample selection. Our sample of LAEs are selected based on their continuum magnitudes and they probe higher continuum luminosities compared to narrow-band/emission line selected LAEs. Based on our results, it is important to note that all LAEs are not universally similar and their properties are strongly dependent on the sample selection, and/or continuum luminosities.
description: 4 pages: To be published in the proceedings of IAU symposium 319, "Galaxies at High Redshift and Their Evolution over Cosmic Time"
A class of spherical, truncated, anisotropic models for application to globular clusters
Creators: name: de Vita, Ruggero
name: Bertin, Giuseppe
name: Zocchi, Alice
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Recently, a class of non-truncated radially-anisotropic models (the so-called $f^{(ν)}$-models), originally constructed in the context of violent relaxation and modeling of elliptical galaxies, has been found to possess interesting qualities in relation to observed and simulated globular clusters. In view of new applications to globular clusters, we improve this class of models along two directions. To make them more suitable for the description of small stellar systems hosted by galaxies, we introduce a 'tidal' truncation (by means of a procedure that guarantees full continuity of the distribution function). The new $f_T^{(ν)}$-models are shown to provide a better fit to the observed photometric and spectroscopic profiles for a sample of 13 globular clusters studied earlier by means of non-truncated models; interestingly, the best-fit models also perform better with respect to the radial-orbit instability. Then we design a flexible but simple two-component family of truncated models, to study the separate issues of mass segregation and of multiple populations. We do not aim at a fully realistic description of globular clusters, to compete with the description currently obtained by means of dedicated simulations. The goal here is to try to identify the simplest models, that is, those with the smallest number of free parameters, but still able to provide a reasonable description for clusters that are evidently beyond the reach of one-component models: with this tool we aim at identifying the key factors that characterize mass segregation or the presence of multiple populations. To reduce the relevant parameter space, we formulate a few physical arguments (based on recent observations and simulations). A first application to two well-studied globular clusters is briefly described and discussed.
description: 15 pages, 13 figures, Accepted for publication in Astronomy & Astrophysics
The global warming of group satellite galaxies
Creators: name: Yozin, C
name: Bekki, K
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Recent studies adopting $λ_{\rm Re}$, a proxy for specific angular momentum, have highlighted how early-type galaxies (ETGs) are composed of two kinematic classes for which distinct formation mechanisms can be inferred. With upcoming surveys expected to obtain $λ_{\rm Re}$ from a broad range of environments (e.g. SAMI, MaNGA), we investigate in this numerical study how the $λ_{\rm Re}$-$ε_{\rm e}$ distribution of fast-rotating dwarf satellite galaxies reflects their evolutionary state. By combining N-body/SPH simulations of progenitor disc galaxies (stellar mass $\simeq$10$^{\rm 9}$ M$_{\odot}$), their cosmologically-motivated sub-halo infall history and a characteristic group orbit/potential, we demonstrate the evolution of a satellite ETG population driven by tidal interactions (e.g. harassment). As a general result, these satellites remain intrinsically fast-rotating oblate stellar systems since their infall as early as $z=2$; mis-identifications as slow rotators often arise due to a bar/spiral lifecycle which plays an integral role in their evolution. Despite the idealistic nature of its construction, our mock $λ_{\rm Re}$-$ε_{\rm e}$ distribution at $z<0.1$ reproduces its observational counterpart from the ATLAS$^{\rm 3D}$/SAURON projects. We predict therefore how the observed $λ_{\rm Re}$-$ε_{\rm e}$ distribution of a group evolves according to these ensemble tidal interactions.
description: 8 pages, 2 tables, 6 figures, accepted for publication in MNRAS
Quantum epistemology from subquantum ontology: quantum mechanics from theory of classical random fields
Creators: name: Khrennikov, Andrei
Publisher: name: arXiv
Year: 2016
Subjects: subject: Quantum Physics (quant-ph)
subject: History and Philosophy of Physics (physics.hist-ph)
subject: Popular Physics (physics.pop-ph)
subject: FOS: Physical sciences

description: The scientific methodology based on two descriptive levels, ontic (reality as it is ) and epistemic (observational), is briefly presented. Following Schrödinger, we point to the possible gap between these two descriptions. Our main aim is to show that, although ontic entities may be inaccessible for observations, they can be useful for clarification of the physical nature of operational epistemic entities. We illustrate this thesis by the concrete example: starting with the concrete ontic model preceding quantum mechanics (the latter is treated as an epistemic model), namely, prequantum classical statistical field theory (PCSFT), we propose the natural physical interpretation for the basic quantum mechanical entity - the quantum state ("wave function"). The correspondence PCSFT to QM is not straightforward, it couples the covariance operators of classical (prequantum) random fields with the quantum density operators. We use this correspondence to clarify the physical meaning of the pure quantum state and the superposition principle - by using the formalism of classical field correlations.
The Detection of Dust around NN Ser
Creators: name: Hardy, Adam
name: Schreiber, Matthias R.
name: Parsons, Steven G.
name: Caceres, Claudio
name: Brinkworth, Carolyn
name: Veras, Dimitri
name: Gaensicke, Boris T.
name: Marsh, Thomas R.
name: Cieza, Lucas
Publisher: name: arXiv
Year: 2016
Subjects: subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: FOS: Physical sciences

description: Eclipse timing variations observed from the post common-envelope binary (PCEB) NN Ser offer strong evidence in favour of circumbinary planets existing around PCEBs. If real, these planets may be accompanied by a disc of dust. We here present the ALMA detection of flux at 1.3 mm from NN Ser, which is likely due to thermal emission from a dust disc of mass $\sim0.8\pm0.2\,M_{\oplus}$. We performed simulations of the history of NN Ser to determine possible origins of this dust, and conclude that the most likely origin is, in fact, common-envelope material which was not expelled from the system and instead formed a circumbinary disc. These discs have been predicted by theory but previously remained undetected. While the presence of this dust does not prove the existence of planets around NN Ser, it adds credibility to the possibility of planets forming from common-envelope material in a 'second-generation' scenario.
description: resubmitted after minor revision to MNRAS
Effective Field Theory of Dark Matter: a Global Analysis
Creators: name: Liem, Sebastian
name: Bertone, Gianfranco
name: Calore, Francesca
name: de Austri, Roberto Ruiz
name: Tait, Tim M. P.
name: Trotta, Roberto
name: Weniger, Christoph
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: We present global fits of an effective field theory description of real, and complex scalar dark matter candidates. We simultaneously take into account all possible dimension 6 operators consisting of dark matter bilinears and gauge invariant combinations of quark and gluon fields. We derive constraints on the free model parameters for both the real (five parameters) and complex (seven) scalar dark matter models obtained by combining Planck data on the cosmic microwave background, direct detection limits from LUX, and indirect detection limits from the Fermi Large Area Telescope. We find that for real scalars indirect dark matter searches disfavour a dark matter particle mass below 100 GeV. For the complex scalar dark matter particle current data have a limited impact due to the presence of operators that lead to p-wave annihilation, and also do not contribute to the spin-independent scattering cross- section. Although current data are not informative enough to strongly constrain the theory parameter space, we demonstrate the power of our formalism to reconstruct the theoretical parameters compatible with an actual dark matter detection, by assuming that the excess of gamma rays observed by the Fermi Large Area Telescope towards the Galactic centre is entirely due to dark matter annihilations. Please note that the excess can very well be due to astrophysical sources such as millisecond pulsars. We find that scalar dark matter interacting via effective field theory operators can in principle explain the Galactic centre excess, but that such interpretation is in strong tension with the non-detection of gamma rays from dwarf galaxies in the real scalar case. In the complex scalar case there is enough freedom to relieve the tension.
description: 20 pages, 5 figures
An efficient finite-difference scheme for computation of electron states in free-standing and core-shell quantum wires
Creators: name: Arsoski, V. V.
name: Tadic, M. Z.
name: Cukaric, N. A.
name: Peeters, F. M.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: The electron states in axially symmetric quantum wires are computed by means of the effective-mass Schroedinger equation, which is written in cylindrical coordinates phi, rho, and z. We show that a direct discretization of the Schroedinger equation by central finite differences leads to a non-symmetric Hamiltonian matrix. Because diagonalization of such matrices is more complex it is advantageous to transform it in a symmetric form. This can be done by the Liouville-like transformation proposed by Rizea et al. (Comp. Phys. Comm. 179 (2008) 466-478), which replaces the wave function psi(rho) with the function F(rho)=psi(rho)sqrt(rho) and transforms the Hamiltonian accordingly. Even though a symmetric Hamiltonian matrix is produced by this procedure, the computed wave functions are found to be inaccurate near the origin, and the accuracy of the energy levels is not very high. In order to improve on this, we devised a finite-difference scheme which discretizes the Schroedinger equation in the first step, and then applies the Liouville-like transformation to the difference equation. Such a procedure gives a symmetric Hamiltonian matrix, resulting in an accuracy comparable to the one obtained with the finite element method. The superior efficiency of the new finite-difference (FDM) scheme is demonstrated for a few rho-dependent one-dimensional potentials which are usually employed to model the electron states in free-standing and core-shell quantum wires. The new scheme is compared with the other FDM schemes for solving the effective-mass Schroedinger equation, and is found to deliver energy levels with much smaller numerical error for all the analyzed potentials. Moreover, the PT symmetry is invoked to explain similarities and differences between the considered FDM schemes.
Hot ammonia around young O-type stars. III. High-mass star formation and hot core activity in W51~Main
Creators: name: Goddi, Ciriaco
name: Ginsburg, Adam
name: Zhang, Qizhou
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: This paper is the third in a series of ammonia multilevel imaging studies in well-known high-mass star forming regions. Using the JVLA, we have mapped the hot and dense molecular gas in W51 Main, with about 0.2 arcsec angular resolution, in five highly-excited metastable inversion transitions of ammonia (ammonia): (J,K)=(6,6), (7,7), (9,9), (10,10), and (13,13). We have identified and characterised two main centers of high-mass star formation in W51-Main: the W51e2 complex and the W51e8 core (6 arcsec southward of W51e2). The former breaks down into three further sub-cores: W51e2-W, which surrounds the well known HC HII region, where hot ammonia is observed in absorption, and two additional dusty cores, W51e2-E (~0.8" to the East) and W51e2-NW (~1" to the North), where hot ammonia is observed in emission. The velocity maps towards the HC HII region show a clear velocity gradient that may indicate rotation, though we do not directly observe a Keplerian velocity profile. The absence of outflow and/or maser activity and the low amount of molecular gas available for accretion (~5 solar masses) with respect to the mass of the central YSO (>20 solar masses), both indicate that the central YSO has already accreted most of its final mass. On the other hand, in the nearby W51e2-E object, the relatively large amount of hot molecular gas available for accretion (~20 solar masses, within about half an arcsecond or 2500 AU), along with strong outflow and maser activity, indicates that the main accretion center in the W51e2 complex is W51e2-E rather than W51e2-W. Finally, W51e2-NW and W51e8, although less dense, are also hot cores and contain a significant amount of molecular gas (~30 and 70 solar masses, respectively). We speculate that they may host high-mass YSOs either at a previous evolutionary stage or with lower mass than W51e2-E and W51e2-W.
description: 23 pages, 21 figures, accepted by Astronomy & Astrophysics
A Frequency Domain Test for Propriety of Complex-Valued Vector Time Series
Creators: name: Chandna, Swati
name: Walden, Andrew T.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Methodology (stat.ME)
subject: Applications (stat.AP)
subject: FOS: Computer and information sciences

description: This paper proposes a frequency domain approach to test the hypothesis that a complex-valued vector time series is proper, i.e., for testing whether the vector time series is uncorrelated with its complex conjugate. If the hypothesis is rejected, frequency bands causing the rejection will be identified and might usefully be related to known properties of the physical processes. The test needs the associated spectral matrix which can be estimated by multitaper methods using, say, $K$ tapers. Standard asymptotic distributions for the test statistic are of no use since they would require $K \rightarrow \infty,$ but, as $K$ increases so does resolution bandwidth which causes spectral blurring. In many analyses $K$ is necessarily kept small, and hence our efforts are directed at practical and accurate methodology for hypothesis testing for small $K.$ Our generalized likelihood ratio statistic combined with exact cumulant matching gives very accurate rejection percentages and outperforms other methods. We also prove that the statistic on which the test is based is comprised of canonical coherencies arising from our complex-valued vector time series.Our methodology is demonstrated on ocean current data collected at different depths in the Labrador Sea. Overall this work extends results on propriety testing for complex-valued vectors to the complex-valued vector time series setting.
description: 13 pages, 3 figures. Methodology (stat.ME), Applications (stat.AP)
Thermodynamics of charged rotating dilaton black branes coupled to logarithmic nonlinear electrodynamics
Creators: name: Sheykhi, A.
name: Dehghani, M. H.
name: Zangeneh, M. Kord
Publisher: name: arXiv
Year: 2016
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: We construct a new class of charged rotating black brane solutions in the presence of logarithmic nonlinear electrodynamics with complete set of the rotation parameters in arbitrary dimensions. The topology of the horizon of these rotating black branes are flat, while, due to the presence of the dilaton field the asymptotic behaviour of them are neither flat nor (anti)-de Sitter [(A)dS]. We investigate the physical properties of the solutions. The mass and angular momentum of the spacetime are obtained by using the counterterm method inspired by AdS/CFT correspondence. We derive temperature, electric potential and entropy associated with the horizon and check the validity of the first law of thermodynamics on the black brane horizon. We study thermal stability of the solutions in both canonical and grand canonical ensemble and disclose the effects of the rotation parameter, nonlinearity of electrodynamics and dilaton field on the thermal stability conditions. We find the solutions are thermally stable for $α<1$, while for $α>1$ the solutions may encounter an unstable phase where $α$ is dilaton-electromagnetic coupling constant.
description: 15 pages, 11 figures
Pressure-induced phase transformation in zircon-type orthovanadate SmVO4 from experiment and theory
Creators: name: Popescu, C
name: Garg, Alka B
name: Errandonea, D
name: Sans, J A
name: Rodriguez-Hernandez, P
name: Radescu, S
name: Munoz, A
name: Achary, S N
name: Tyagi, A K
Publisher: name: arXiv
Year: 2016
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences
subject: 86

description: The compression behavior of zircon-type samarium orthovanadate, SmVO4, has been investigated using synchrotron-based powder x-ray diffraction and ab-initio calculations up to 21 GPa. The results indicate the instability of ambient zircon phase at around 6 GPa, which transforms to a high-density scheelite-type phase. The high-pressure phase remains stable up to 21 GPa, the highest pressure reached in the present investigations. On pressure release, the scheelite phase is recovered. Crystal structure of high-pressure phase and equations of state (EOS) for the zircon- and scheelite-type phases have been determined. Various compressibilities such as bulk, axial and bond, estimated from the experimental data are found to be in good agreement with the results obtained from theoretical calculations. Calculated elastic constants show that the zircon structure becomes mechanically unstable beyond the transition pressure. Overall there is good agreement between experimental and theoretical findings.
description: 13 pages, 12 figures, 3 tables
Electric coupling in scanning SQUID measurements
Creators: name: Spanton, Eric M.
name: Rosenberg, Aaron J.
name: Wang, Yihua H.
name: Kirtley, John R.
name: Katmis, Ferhat
name: Jarillo-Herrero, Pablo
name: Moodera, Jagadeesh S.
name: Moler, Kathryn A.
Publisher: name: arXiv
Year: 2015
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Scanning SQUID is a local magnetometer which can image flux through its pickup loop due to DC magnetic fields ($Φ$). Scanning SQUID can also measure a sample's magnetic response to an applied current ($dΦ/dI$) or voltage ($dΦ/dV$) using standard lock-in techniques. In this manuscript, we demonstrate that electric coupling between the scanning SQUID and a back gate-tuned, magnetic sample can lead to a gate-voltage dependent artifact when imaging $dΦ/dI$ or $dΦ/dV$. The electric coupling artifact results in $dΦ/dV$ and $dΦ/dI$ images which mimic the spatial variation of the static magnetic fields from the sample (e.g. ferromagnetic domains). In back-gated $EuS/Bi_2Se_3$ bilayers, we show that the electric coupling effect is important, and is responsible for the reported signal from chiral currents in Y.H. Wang, et al. (DOI: 10.1126/science.aaa0508). Previous scanning SQUID current imaging experiments are unaffected by this artifact, as they are either on non-magnetic samples or the spatial distribution of magnetism does not match the features observed in $dΦ/dI$. In conclusion, $dΦ/dI$ or $dΦ/dV$ imaging of magnetic, back-gated samples should only be applied and interpreted with great caution.
description: This is a comment on Y.H. Wang, et al. (DOI: 10.1126/science.aaa0508), which has been retracted (DOI: 10.1126/science.350.6267.1482-a)
High resolution spectroscopic analysis of seven giants in the bulge globular cluster NGC 6723
Creators: name: Rojas-Arriagada, A.
name: Zoccali, M.
name: Vásquez, S.
name: Ripepi, V.
name: Musella, I.
name: Marconi, M.
name: Grado, A.
name: Limatola, L.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Globular clusters associated with the Galactic bulge are important tracers of stellar populations in the inner Galaxy. High resolution analysis of stars in these clusters allows us to characterize them in terms of kinematics, metallicity, and individual abundances, and to compare these fingerprints with those characterizing field populations. We present iron and element ratios for seven red giant stars in the globular cluster NGC~6723, based on high resolution spectroscopy. High resolution spectra ($R\sim48~000$) of seven K giants belonging to NGC 6723 were obtained with the FEROS spectrograph at the MPG/ESO 2.2m telescope. Photospheric parameters were derived from $\sim130$ FeI and FeII transitions. Abundance ratios were obtained from line-to-line spectrum synthesis calculations on clean selected features. An intermediate metallicity of [Fe/H]$=-0.98\pm0.08$ dex and a heliocentric radial velocity of $v_{hel}=-96.6\pm1.3~km s^{-1}$ were found for NGC 6723. Alpha-element abundances present enhancements of $[O/Fe]=0.29\pm0.18$ dex, $[Mg/Fe]=0.23\pm0.10$ dex, $[Si/Fe]=0.36\pm0.05$ dex, and $[Ca/Fe]=0.30\pm0.07$ dex. Similar overabundance is found for the iron-peak Ti with $[Ti/Fe]=0.24\pm0.09$ dex. Odd-Z elements Na and Al present abundances of $[Na/Fe]=0.00\pm0.21$ dex and $[Al/Fe]=0.31\pm0.21$ dex, respectively. Finally, the s-element Ba is also enhanced by $[Ba/Fe]=0.22\pm0.21$ dex. The enhancement levels of NGC 6723 are comparable to those of other metal-intermediate bulge globular clusters. In turn, these enhancement levels are compatible with the abundance profiles displayed by bulge field stars at that metallicity. This hints at a possible similar chemical evolution with globular clusters and the metal-poor of the bulge going through an early prompt chemical enrichment.
Star-forming galaxies versus low- and high-excitation radio AGN in the VLA-COSMOS 3GHz Large Project
Creators: name: Baran, N.
name: Smolčić, V.
name: Novak, M.
name: Delhaize, J.
name: Delvecchio, I.
name: Capak, P.
name: Civano, F.
name: Herrera-Ruiz, N.
name: Ilbert, O.
name: Laigle, C.
name: Marchesi, S.
name: McCracken, H. J.
name: Middelberg, E.
name: Salvato, M.
name: Schinnerer, E.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences
subject: 85-06

description: We study the composition of the faint radio population selected from the VLA-COSMOS 3GHz Large Project, a radio continuum survey performed at 10 cm wavelength. The survey covers the full 2 square degree COSMOS field with mean $rms\sim2.3$ $μ$Jy/beam, cataloging 10,899 source components above $5\times rms$. By combining these radio data with UltraVISTA, optical, near-infrared, and Spitzer/IRAC mid-infrared data, as well as X-ray data from the Chandra Legacy, and Chandra COSMOS surveys, we gain insight into the emission mechanisms within our radio sources out to redshifts of $z\sim5$. From these emission characteristics we classify our souces as star forming galaxies or AGN. Using their multi-wavelength properties we further separate the AGN into sub-samples dominated by radiatively efficient and inefficient AGN, often referred to as high- and low-excitation emission line AGN. We compare our method with other results based on fitting of the sources' spectral energy distributions using both galaxy and AGN spectral models, and those based on the infrared-radio correlation. We study the fractional contributions of these sub-populations down to radio flux levels of $\sim$10 $μ$Jy. We find that at 3 GHz flux densities above $\sim$400 $μ$Jy quiescent, red galaxies, consistent with the low-excitation radio AGN class constitute the dominant fraction. Below densities of $\sim$200 $μ$Jy star-forming galaxies begin to constitute the largest fraction, followed by the low-excitation, and X-ray- and IR-identified high-excitation radio AGN.
description: 7 pages, 3 figures, The many facets of extragalactic radio surveys: towards new scientific challenges, Bologna 20-23 October 2015
The growth of disks and bulges during hierarchical galaxy formation. I: fast evolution vs secular processes
Creators: name: Tonini, Chiara
name: Mutch, Simon J.
name: Croton, Darren J.
name: Wyithe, J. Stuart B.
Publisher: name: arXiv
Year: 2016
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We present a theoretical model for the evolution of mass, angular momentum and size of galaxy disks and bulges, and we implement it into the semi-analytic galaxy formation code SAGE. The model follows both secular and violent evolutionary channels, including smooth accretion, disk instabilities, minor and major mergers. We find that the combination of our recipe with hierarchical clustering produces two distinct populations of bulges: merger-driven bulges, akin to classical bulges and ellipticals, and instability-driven bulges, akin to secular (or pseudo-)bulges. The model mostly reproduces the mass-size relation of gaseous and stellar disks, the evolution of the mass-size relation of ellipticals, the Faber-Jackson relation, and the magnitude-colour diagram of classical and secular bulges. The model predicts only a small overlap of merger-driven and instability-driven components in the same galaxy, and predicts different bulge types as a function of galaxy mass and disk fraction. Bulge type also affects the star formation rate and colour at a given luminosity. The model predicts a population of merger-driven red ellipticals that dominate both the low-mass and high-mass ends of the galaxy population, and span all dynamical ages; merger-driven bulges in disk galaxies are dynamically old and do not interfere with subsequent evolution of the star-forming component. Instability-driven bulges dominate the population at intermediate galaxy masses, especially thriving in massive disks. The model green valley is exclusively populated by instability-driven bulge hosts. Through the present implementation the mass accretion history is perceivable in the galaxy structure, morphology and colours.
description: Accepted on MNRAS; 24 pages, 11 figures
A particle-like description of Planckian black holes
Creators: name: Spallucci, Euro
name: Smailagic, Anais
Publisher: name: arXiv
Year: 2016
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: In this paper we abandon the idea that even a "quantum" black hole, of Planck size, can still be described as a classical, more or less complicated, geometry. Rather, we consider a genuine quantum mechanical approach where a Planckian black hole is, by all means, just another "particle", even if with a distinguishing property: its linear size increases with the energy. The horizon dynamics is equivalently described in terms of a particle moving in gravitational potential derived from the horizon equation itself in a self-consistent manner. The particle turning-points match the radius of the inner and outer horizons of a charged black hole. This classical model pave the way towards the wave equation for a truly quantum black hole. We compute the exact form of the wave function and determine the energy spectrum. Finally, we describe the classical limit in which the quantum picture correctly approaches the classical geometric formulation. We find that the quantum-to-classical transition occurs far above the Planck scale.
description: 22 pages, 8 Figures. Draft of the invited contribution to the book: "Quantum Gravity: Theory and Research" Nova Science Publishers, Inc
Hollow nuclear matter
Creators: name: Yong, Gao-Chan
Publisher: name: arXiv
Year: 2015
Subjects: subject: Nuclear Theory (nucl-th)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: It is generally considered that an atomic nucleus is always compact. Based on the isospin-dependent Boltzmann nuclear transport model, here I show that large block nuclear matter or excited nuclear matter may both be hollow. And the size of inner bubble in these matter is affected by the charge number of nuclear matter. Existence of hollow nuclear matter may have many implications in nuclear or atomic physics or astrophysics as well as some practical applications.
description: 5 pages, 6 figures, PRC, in production
Retrieval of Precise Radial Velocities from Near-Infrared High Resolution Spectra of Low Mass Stars
Creators: name: Gao, Peter
name: Plavchan, Peter
name: Gagné, Jonathan
name: Furlan, Elise
name: Bottom, Michael
name: Anglada-Escudé, Guillem
name: White, Russel
name: Davison, Cassy
name: Beichman, Charles
name: Brinkworth, Carolyn
name: Johnson, John
name: Ciardi, David
name: Wallace, James
name: Mennesson, Bertrand
name: von Braun, Kaspar
name: Vasisht, Gautam
name: Prato, Lisa
name: Kane, Stephen
name: Tanner, Angelle
name: Crawford, Timothy
name: Latham, David
name: Rougeot, Raphaël
name: Geneser, Claire
name: Catanzarite, Joseph
Publisher: name: arXiv
Year: 2016
Subjects: subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Given that low-mass stars have intrinsically low luminosities at optical wavelengths and a propensity for stellar activity, it is advantageous for radial velocity (RV) surveys of these objects to use near-infrared (NIR) wavelengths. In this work we describe and test a novel RV extraction pipeline dedicated to retrieving RVs from low mass stars using NIR spectra taken by the CSHELL spectrograph at the NASA Infrared Telescope Facility, where a methane isotopologue gas cell is used for wavelength calibration. The pipeline minimizes the residuals between the observations and a spectral model composed of templates for the target star, the gas cell, and atmospheric telluric absorption; models of the line spread function, continuum curvature, and sinusoidal fringing; and a parameterization of the wavelength solution. The stellar template is derived iteratively from the science observations themselves without a need for separate observations dedicated to retrieving it. Despite limitations from CSHELL's narrow wavelength range and instrumental systematics, we are able to (1) obtain an RV precision of 35 m/s for the RV standard star GJ 15 A over a time baseline of 817 days, reaching the photon noise limit for our attained SNR, (2) achieve ~3 m/s RV precision for the M giant SV Peg over a baseline of several days and confirm its long-term RV trend due to stellar pulsations, as well as obtain nightly noise floors of ~2 - 6 m/s, and (3) show that our data are consistent with the known masses, periods, and orbital eccentricities of the two most massive planets orbiting GJ 876. Future applications of our pipeline to RV surveys using the next generation of NIR spectrographs, such as iSHELL, will enable the potential detection of Super-Earths and Mini-Neptunes in the habitable zones of M dwarfs.
description: 64 pages, 28 figures, 5 tables. Accepted for publication in PASP
CINECA: Report on trust model for partner sites, and between sites and controlled-access researchers
Creators: name: Cirillo, Elisa
name: Alasoo, Kaur
name: Michie, Alex
name: Binsl, Thomas
name: Törnroos, Juha
name: Kapoor, Shubham
name: Tsukanov, Kirill
name: Rayner, William
name: Mbiyavanga, Mamana
name: Rashid, Shaikh
name: Westra, Harm-Jan
Publisher: name: Zenodo
Year: 2020
Subjects: Trust model, Controlled access, Data access, Federated analysis

description: In this deliverable document, we report on the activities for Deliverable 4.1 - Report on trust model for partner sites, and between sites and controlled-access researchers. The Work Package 4 goals concern the development of a set of tools that can facilitate federated analyses of new and diverse genetic and genomic datasets, based on specific use cases. The tools selected will be using the common federated infrastructure established in earlier work packages, and the datasets will be described with metadata standards identified in Work Package 3.
 In our report we considered trust as the extent to which one party is willing to depend on the other party in a given situation with a feeling of relative security, even though negative consequences are possible. This work has contributed towards establishing a description of the trust model and four different levels of data access concerning specific cohort’s data, identifying use cases for the development of federated analysis workflows and describing existing data access models to inspire subsequent WP4 deliverables related to the implementation of the federated analysis workflow.
ICT big size projects in Outsourcing with BPR. The agile scenario. Academic vs actual dynamics and effectiveness in a prone to uncertainty environment
Creators: name: Bellinger, Giorgio
Publisher: name: Zenodo
Year: 2023
Subjects: ICT
Outourcing
Project Management
Business Administration
Agility
Flexibility
Business Strategy
Business
Business Process

description: Nowadays, many organizations know and extensively apply outsourcing practices. The reasons that should justify the adoption of this practice dwell on the search for lowering labour costs, for accessing not available expertise, for achieving flexibility and, more in general, for pursuing competitive advantage. Although a huge amount of failures seems to indicate as this practice is not as proficient as expected, no one seems to tackle the preconception related to its suitability. It could indicate an under-evaluation of the real impact of the outsourcing practice by organizations and, in turn, it could indicate the limits of the process aimed to evaluate “the how” (meant as tactics). It is ascribable to a decision-making process that very likely is inspired to the quantitative business management perspective. Unfortunately, the complexity of the real scenarios could really strain the reduction of their “whole” into many, single, manageable chunks of work. It could be particularly true in an ICT context. Also ICT employees (as member of a supportive element of the value chain) well know how this practice can impact themselves so that motivating them could be nonsense in several situations. Within the above boundaries, our interest concerns the dynamics of Outsourcing practices applied to ICT (i.e. Information and Communication Technologies) SW (i.e. software) Solutions with BPR (i.e business process reengineering). Uncertainty and next complexity of the proposed scenario would not justify a per “best-practices” approach so that they are additional reasons for investigation. They further constrain Project Managers to adopt an Agile paradigm. Knowledge Areas of PM practices will be also considered.
title: Can explicit processes support implicit category learning?: The effect of relevant rule-oriented selective attention on implicit learning
Creators: name: Sanchez, Andres
Publisher: name: Georgia State University
Year: 2023

description:
Categorization is a crucial component of human cognition. Multiple systems theories suggest categories can be learned by explicit or implicit processes/systems depending on the type of category (e.g., Ashby & Valentin, 2017). Research examining the interaction between these systems found that explicit learning impairs implicit performance (Ashby & Crossley, 2010; Crossley & Ashby, 2015; Sanchez et al., 2020). The nature of this impairment remains unclear. The current study examined the effect of selective attention to rule dimensions that were either relevant or irrelevant to a later implicit categorization task to better understand how this impairment occurs. The results suggested that attention to relevant dimensions is crucial for implicit learning. Both systems can learn in parallel as long as the relevant category information is attended. This suggests the primary mechanism of implicit impairment by the explicit system may be drawing attention away from relevant information rather than rule-based strategy perseveration.
A High-Precision NIR Survey for RV Variable Low-Mass Stars
Creators: name: Gagné, Jonathan
name: Plavchan, Peter
name: Gao, Peter
name: Anglada-Escude, Guillem
name: Furlan, Elise
name: Davison, Cassy
name: Tanner, Angelle
name: Henry, Todd J.
name: Riedel, Adric R.
name: Brinkworth, Carolyn
name: Latham, David
name: Bottom, Michael
name: White, Russel
name: Mills, Sean
name: Beichman, Chas
name: Johnson, John A.
name: Ciardi, David R.
name: Wallace, Kent
name: Mennesson, Bertrand
name: von Braun, Kaspar
name: Vasisht, Gautam
name: Prato, Lisa
name: Kane, Stephen R.
name: Mamajek, Eric E.
name: Walp, Bernie
name: Crawford, Timothy J.
name: Rougeot, Raphaël
name: Geneser, Claire S.
name: Catanzarite, Joseph
Publisher: name: arXiv
Year: 2016
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Earth and Planetary Astrophysics (astro-ph.EP)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: We present the results of a precise near-infrared (NIR) radial velocity (RV) survey of 32 low-mass stars with spectral types K2-M4 using CSHELL at the NASA IRTF in the $K$-band with an isotopologue methane gas cell to achieve wavelength calibration and a novel iterative RV extraction method. We surveyed 14 members of young ($\approx$ 25-150 Myr) moving groups, the young field star $\varepsilon$ Eridani as well as 18 nearby ($
description: 29 pages, 16 figures, 6 tables. Accepted for publication in ApJ