cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Probing the profile of bulk matter in p+Pb collisions via directed flow of heavy quarks
Creators: name: Haque, Md Rihan
name: Singha, Subhash
name: Mohanty, Bedangadas
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The asymmetric initial geometry in p+Pb collisions provide an opportunity to probe the initial matter distribution in these collisions. Using A Multi-Phase Transport (AMPT) model, we have studied the production of light and heavy quark particles in p+Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. The pseudo-rapidity density (dN/d$η$) and elliptic flow ($v_{2}$) of light-quark particles from AMPT reasonably agrees with the measurements by ALICE. We predicted the directed flow of light and heavy quarks in p+Pb collisions. The $v_{1}$ of both light and heavy-quark mesons show a non-trivial $p_{T}$ dependence in p- and Pb-going directions. When integrated over the transverse momentum range 0 $ < p_{T} < $5 GeV/c, the magnitude of heavy quark directed flow ($v_{1}$) is found to be 15 times larger than the light quark species in the Pb-going direction while the same in the p-going direction are comparable. The light and heavy quarks $v_{1}$ may offer the possibility to probe the initial matter density as well as the collective dynamics in p+Pb collisions
description: 7 pages, 9 figures
Correlated bosons on a lattice: Dynamical mean-field theory for Bose-Einstein condensed and normal phases
Creators: name: Byczuk, Krzysztof
name: Vollhardt, Dieter
Publisher: name: arXiv
Year: 2007
Subjects: subject: Other Condensed Matter (cond-mat.other)
subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: We formulate a bosonic dynamical mean-field theory (B-DMFT) which provides a comprehensive, thermodynamically consistent framework for the theoretical investigation of correlated lattice bosons. The B-DMFT is applicable for arbitrary values of the coupling parameters and temperature and becomes exact in the limit of high spatial dimensions d or coordination number Z of the lattice. In contrast to its fermionic counterpart the construction of the B-DMFT requires different scalings of the hopping amplitudes with Z depending on whether the bosons are in their normal state or in the Bose-Einstein condensate. A detailed discussion of how this conceptual problem can be overcome by performing the scaling in the action rather than in the Hamiltonian itself is presented. The B-DMFT treats normal and condensed bosons on equal footing and thus includes the effects caused by their dynamic coupling. It reproduces all previously investigated limits in parameter space such as the Beliaev-Popov and Hartree-Fock-Bogoliubov approximations and generalizes the existing mean-field theories of interacting bosons. The self-consistency equations of the B-DMFT are those of a bosonic single-impurity coupled to two reservoirs corresponding to bosons in the condensate and in the normal state, respectively. We employ the B-DMFT to solve a model of itinerant and localized, interacting bosons analytically. The local correlations are found to enhance the condensate density and the Bose-Einstein condensate (BEC) transition temperature T_{BEC}. This effect may be used experimentally to increase T_{BEC} of bosonic atoms in optical lattices.
description: 17 pages, 4 figures, extended version
Diffusivity in force-free simulations of global magnetospheres
Creators: name: Mahlmann, J. F.
name: Aloy, M. A.
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Instrumentation and Methods for Astrophysics (astro-ph.IM)
subject: FOS: Physical sciences

description: Abstract: Assuming that the numerical diffusivity triggered by violations of the force-free electrodynamics constraints is a proxy for the physical resistivity, we examine its impact on the overall dynamics of force-free aligned pulsar magnetospheres endowed with an equatorial current sheet. We assess the constraint violations as a diffusivity source. The effects of modifications on electric fields used to restore force-free conditions are not confined to the equatorial current sheet, but modify the magnetospheric dynamics on timescales shorter than the pulsar rotational period. These corrections propagate especially via a channel that was unexplored, namely, changes induced to the electric charge density, $ρ$. We quantify the global consequences of diffusivity by comparing different techniques to model $ρ$. By default, we combine a conservative $ρ$-evolution with hyperbolic/parabolic cleaning of inaccuracies in the Maxwell equations. As an alternative, we enforce a constrained evolution where $ρ$ is directly computed as the electric field divergence. The conservative approach reduces the Poynting flux dissipated in the equatorial current sheet by an order of magnitude, along with an increase of the pulsar luminosity driven by a shift of the Y-point location. The luminosity changes according to $L_{\rm Y}\propto α^{0.11}$, where $α$ is the ratio of diffusion to advection timescales, controlling the amount of (numerical) diffusivity. Our models suggest interpreting the luminosity dependence on the Y-point location as differences in resistivities encountered at the equatorial current sheet. Alternatively, they could be interpreted in terms of the pair formation multiplicity, $κ$, smaller diffusion being consistent with $κ\gg 1$.
description: (17 pages, 9 figures, Accepted by MNRAS)
Less developed countries and market access for manufactured exports : North-South bargaining and the quest for reform
Creators: name: Finlayson, Jock A.
Publisher: name: University of British Columbia
Year: 2010

description: This study examines the evolution of international negotiations between the developed and developing countries in connection with the attempts of the latter to obtain improved access to the markets of the rich industrial countries for exports of manufactured products. The primary focus is on the bargaining which has taken place in two distinct institutional settings—the General Agreement on Tariffs and Trade (GATT), and the United Nations Conference on Trade and Development (UNCTAD). Although the period covered by the study is the entire thirty-five years since the end of the Second World War, most of the discussion relates to the period since 1964, the year of UNGTAD's creation. In seeking to explain both the successes and failures of the developing countries in their efforts to obtain improved market access, use is made of several different analytical approaches currently employed by international relations scholars. A major concern of the study is to analyze how valuable or insightful these various approaches appear to be with respect to the particular case under examination here. Some schools of thought ascribe considerable bargaining power to relatively weak actors in international politics, but in case of manufactured exports the developing countries, who lack influence in this issue area, are shown to possess little leverage in negotiating for better access to the markets of developed economies. It is the vulnerability and weakness of developing countries that must be stressed in seeking to portray how they are situated in relation to this important area of international political and economic relations.
Reddening law and interstellar dust properties along Magellanic sight-lines
Creators: name: Zagury, Frederic
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: This study establishes that SMC, LMC and Milky Way extinction curves obey the same extinction law which depends on the 2200A bump size and one parameter, and generalizes the Cardelli, Clayton and Mathis (1989) relationship. This suggests that extinction in all three galaxies is of the same nature. The role of linear reddening laws over all the visible/UV wavelength range, particularly important in the SMC but also present in the LMC and in the Milky Way, is also highlighted and discussed.
description: accepted for publication in Astrophysics and Space Science. 16 pages, 12 figures. Some figures are colour plots
An in-depth Analysis of Occasional and Recurring Collaborations in Online Music Co-creation
Creators: name: Calefato, Fabio
name: Iaffaldano, Giuseppe
name: Trisolini, Leonardo
name: Lanubile, Filippo
Publisher: name: arXiv
Year: 2021
Subjects: subject: Human-Computer Interaction (cs.HC)
subject: FOS: Computer and information sciences

description: The success of online creative communities depends on the will of participants to create and derive content in a collaborative environment. Despite their growing popularity, the factors that lead to remixing existing content in online creative communities are not entirely understood. In this paper, we focus on overdubbing, that is, a dyadic collaboration where one author mixes one new track with an audio recording previously uploaded by another. We study musicians who collaborate regularly, that is, frequently overdub each other's songs. Building on frequent pattern mining techniques, we develop an approach to seek instances of such recurring collaborations in the Songtree community. We identify 43 instances involving two or three members with a similar reputation in the community. Our findings highlight common and different remix factors in occasional and recurring collaborations. Specifically, fresh and less mature songs are generally overdubbed more; instead, exchanging messages and invitations to collaborate are significant factors only for songs generated through recurring collaborations whereas author reputation (ranking) and applying metadata tags to songs have a positive effect only in occasional collaborations.
Up-conversion injection in Rubrene/Perylene-diimide-heterostructure electroluminescent diodes
Creators: name: Pandey, Ajay K.
name: Nunzi, Jean-Michel
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: Other Condensed Matter (cond-mat.other)
subject: FOS: Physical sciences

description: We implement and demonstrate a scheme that permits to drive electroluminescence with an extremely low turn-on voltage. The device behaves like compound semiconductors, in which the electroluminescence turn-on voltage is about the same as the open circuit voltage for the photovoltaic effect. However, the electroluminescence turn-on voltage is about half of the band gap of the emitting material, that cannot be explained using current models of charge injection in organic semiconductors. We hereby propose explanation through an Auger-type two-step injection mechanism (Auger-fountain).
description: we report the first evidence of an Auger-fountain electroluminescence in a semiconductor heterojunction
Probing Early Super-massive Black Hole Growth and Quasar Evolution with Near-infrared Spectroscopy of 37 Reionization-era Quasars at 6.3 < z <= 7.64
Creators: name: Yang, Jinyi
name: Wang, Feige
name: Fan, Xiaohui
name: Barth, Aaron J.
name: Hennawi, Joseph F.
name: Nanni, Riccardo
name: Bian, Fuyan
name: Davies, Frederick B.
name: Farina, Emanuele P.
name: Schindler, Jan-Torge
name: Banados, Eduardo
name: Decarli, Roberto
name: Eilers, Anna-Christina
name: Green, Richard
name: Guo, Hengxiao
name: Jiang, Linhua
name: Li, Jiang-Tao
name: Venemans, Bram
name: Walter, Fabian
name: Wu, Xue-Bing
name: Yue, Minghao
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: We report the results of near-infrared spectroscopic observations of 37 quasars in the redshift range $6.3< z\le7.64$, including 32 quasars at $z>6.5$, forming the largest quasar near-infrared spectral sample at this redshift. The spectra, taken with Keck, Gemini, VLT, and Magellan, allow investigations of central black hole mass and quasar rest-frame ultraviolet spectral properties. The black hole masses derived from the MgII emission lines are in the range $(0.3-3.6)\times10^{9}\,M_{\odot}$, which requires massive seed black holes with masses $\gtrsim10^{3-4}\,M_{\odot}$, assuming Eddington accretion since $z=30$. The Eddington ratio distribution peaks at $λ_{\rm Edd}\sim0.8$ and has a mean of 1.08, suggesting high accretion rates for these quasars. The CIV - MgII emission line velocity differences in our sample show an increase of CIV blueshift towards higher redshift, but the evolutionary trend observed from this sample is weaker than the previous results from smaller samples at similar redshift. The FeII/MgII flux ratios derived for these quasars up to $z=7.6$, compared with previous measurements at different redshifts, do not show any evidence of strong redshift evolution, suggesting metal-enriched environments in these quasars. Using this quasar sample, we create a quasar composite spectrum for $z>6.5$ quasars and find no significant redshift evolution of quasar broad emission lines and continuum slope, except for a blueshift of the CIV line. Our sample yields a strong broad absorption line quasar fraction of $\sim$24%, higher than the fractions in lower redshift quasar samples, although this could be affected by small sample statistics and selection effects.
description: Accepted for publication in ApJ. 26 pages, 9 figures
The Kl3 scalar form factors in the standard model
Creators: name: Kastner, A.
name: Neufeld, H.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss the predictions of the standard model for the scalar form factors of Kl3 decays. Our analysis is based on the results of chiral perturbation theory, large Nc estimates of low-energy couplings and dispersive methods. It includes a discussion of isospin violating effects of strong and electromagnetic origin.
description: 14 pages, presentation improved, several remarks and references added, results unchanged, to be published in EPJC
Aspects of subordinative composite sentences in the period I oracle bone inscriptions
Creators: name: Chow, Kwok-Ching
Publisher: name: University of British Columbia
Year: 2010

description: Three types of subordinative composite sentence in the O.B.I., i.e., 'cause and effect', 'conditional' and 'simultaneous-successive', are investigated. Since there are no formal connective markers, the logical relationship between two clauses can only be determined on the basis of semantic considerations, the tui-chen pair, the practice of abbreviation and the larger context. A major type of 'cause and effect' sentence is the sentence of the pattern 'wu + V… pu/fu ...' where the second clause represents some undesirable effect or situation. A consideration of the general positive versus negative pattern of the O.B.I. and the practice of abbreviation has led us to adopt the analysis 'cause and effect' for this sentence type. We may interpret sentences in which ch'i appears as conditional. Nevertheless, rather than a pure subordinate marker, the word ch'i is interpreted as a modal conveying the sense of uncertainty, a usage well illustrated in the classics. Also, the theory that treats ch'i as a marker of an embedded sentence has been refuted. The apodoses of 'conditional' and 'simultaneous-successive' sentences may represent an intended result or an undesirable consequence/situation. In most cases, these two types of apodoses can be easily distinguished. But in the case of raining, we have to rely on the idiomatic expressions 'yu vii (wang yu) ' and 'kou yu (pu kou yii) ' in drawing the distinction. In divining about the appropriateness of a proposed activity, the 'conditional' and 'cause and effect' sentences both serve the same purpose. But an activity whose consequence is of greater gravity seems to motivate the employment of the latter. The ritual-sacrificial verbs can be roughly divided into two categories, type A and type B. Type A verbs represent major ritual-sacrificial activities requiring the accompaniment of ritual-sacrificial activities represented by type B verbs which can be placed either in front of or after the type A verbs. The latter case constitutes a conditional or simultaneous-successive sentence, while the former constitutes either a composite sentence incorporating a 'to clause' or a simultaneous-successive sentence.
Cosmological vector modes and quantum gravity effects
Creators: name: Bojowald, Martin
name: Hossain, Golam Mortuza
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: In contrast to scalar and tensor modes, vector modes of linear perturbations around an expanding Friedmann--Robertson--Walker universe decay. This makes them largely irrelevant for late time cosmology, assuming that all modes started out at a similar magnitude at some early stage. By now, however, bouncing models are frequently considered which exhibit a collapsing phase. Before this phase reaches a minimum size and re-expands, vector modes grow. Such modes are thus relevant for the bounce and may even signal the breakdown of perturbation theory if the growth is too strong. Here, a gauge invariant formulation of vector mode perturbations in Hamiltonian cosmology is presented. This lays out a framework for studying possible canonical quantum gravity effects, such as those of loop quantum gravity, at an effective level. As an explicit example, typical quantum corrections, namely those coming from inverse densitized triad components and holonomies, are shown to increase the growth rate of vector perturbations in the contracting phase, but only slightly. Effects at the bounce of the background geometry can, however, be much stronger.
description: 20 pages
The Environmental Dependence of Properties of Galaxies around the RDCSJ0910+54 Cluster at z=1.1
Creators: name: Tanaka, M.
name: Finoguenov, A.
name: Kodama, T.
name: Morokuma, T.
name: Rosati, P.
name: Stanford, S. A.
name: Eisenhardt, P.
name: Holden, B.
name: Mei, S.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: (Abridged) We report on the environmental dependence of properties of galaxies around the RDCSJ0910+54 cluster at z=1.1. We have obtained multi-band wide-field images of the cluster with Suprime-Cam and MOIRCS on Subaru and WFCAM on UKIRT. Also, an intensive spectroscopic campaign has been carried out using LRIS on Keck and FOCAS on Subaru. We discover a possible large-scale structure around the cluster in the form of three clumps of galaxies. This is potentially one of the largest structures found so far in the z>1 Universe. We then examine stellar populations of galaxies in the structure. Red galaxies have already become the dominant population in the cores of rich clusters at z~1, and the fraction of red galaxies has not strongly changed since then. The red fraction depends on richness of clusters in the sense that it is higher in rich clusters than in poor groups. The luminosity function of red galaxies in rich clusters is consistent with that in local clusters. On the other hand, luminosity function of red galaxies in poor groups shows a deficit of faint red galaxies. This confirms our earlier findings that galaxies follow an environment-dependent down-sizing evolution. There seems to be a large variation in the evolutionary phases of galaxies in groups with similar masses. Further studies of high-z clusters will be a promising way of addressing the role of nature and nurture effects on galaxy evolution.
description: 11 pages, 10 figures, accepted for publication in A&A
Population III Star Formation in an X-ray background: II. Protostellar Discs, Multiplicity and Mass Function of the Stars
Creators: name: Park, Jongwon
name: Ricotti, Massimo
name: Sugimura, Kazuyuki
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: FOS: Physical sciences

description: Disc fragmentation plays an important role in determining the number of primordial stars (Pop III stars), their masses, and hence the initial mass function. In this second paper of a series, we explore the effect of uniform FUV H$_2$-photodissociating and X-ray radiation backgrounds on the formation of Pop~III stars using a grid of high-resolution zoom-in simulations. We find that, in an X-ray background, protostellar discs have lower surface density and higher Toomre $Q$ parameter, so they are more stable. For this reason, X-ray irradiated discs undergo fewer fragmentations and typically produce either binary systems or low-multiplicity systems. In contrast, the cases with weak or no X-ray irradiation produce systems with a typical multiplicity of $6 \pm 3$. In addition, the most massive protostar in each system is smaller by roughly a factor of two when the disc is irradiated by X-rays, due to lower accretion rate. With these two effects combined, the initial mass function of fragments becomes more top-heavy in a strong X-ray background and is well described by a power-law with slope $1.53$ and high-mass cutoff of $61$ M$_\odot$. Without X-rays, we find a slope $0.49$ and cutoff mass of $229$ M$_\odot$. Finally, protostars migrate outward after their formation due to the accretion of high-angular momentum gas from outside and the migration is more frequent and significant in absence of X-ray irradiation.
Nisitrus maculosus, new status
Creators: name: Tan, Ming Kai
name: Wahab, Rodzay bin Haji Abdul
name: Japir, Razy
name: Chung, Authur Y. C.
name: Robillard, Tony
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Gryllidae
Nisitrus
Nisitrus maculosus

description: Nisitrus maculosus (Walker, 1871) nomen dubium, new status Table 2
Nisitra maculosa Walker 1871: 14.
Nisitra maculosa – Kirby 1906: 87.
Nisitrus maculosus – Chopard 1968: 353. — Cigliano et al. 2020 (Orthoptera Species File online).
Type locality
Indonesia: Maluka, Seram Island.
Type details
Male, not located.
Remarks
According to the uninformative original description, the type of the species is from Seram Island, while no species of Nisitrus has ever been recorded in the region of Maluku Archipelago (Indonesia). In addition, the description mentions that the eyes are little prominent, and that the FWs extend beyond the abdomen, which is not compatible with any other species of Nisitrus. With the type missing, we consider this species as nomen dubium (new status).
description: Published as part of Tan, Ming Kai, Wahab, Rodzay bin Haji Abdul, Japir, Razy, Chung, Authur Y. C. & Robillard, Tony, 2021, Revision of the cricket genus Nisitrus Saussure (Orthoptera: Gryllidae: Eneopterinae) and descriptions of five new species, pp. 1-75 in European Journal of Taxonomy 761 (1) on page 57, DOI: 10.5852/ejt.2021.761.1449, http://zenodo.org/record/5156259
Antherophagus Latreille 1829
Creators: name: Majka, Christopher
name: Langor, David
Publisher: name: Zenodo
Year: 2010
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Cryptophagidae
Antherophagus

description: Key A. Species of Antherophagus 1. Length over 4.0 mm; habitus broadly oblong. L. 4.0–5.0 mm................................................................................................. Antherophagus ochraceus – Length less than 3.5 mm; habitus narrowly oblong. L. 3.3 mm.............................................................................................. Antherophagus convexulus
description: Published as part of Majka, Christopher & Langor, David, 2010, Contributions towards an understanding of the Cryptophaginae (Coleoptera, Cryptophagidae) of Atlantic Canada, pp. 13-35 in ZooKeys 35 (35) on page 15, DOI: 10.3897/zookeys.35.314, http://zenodo.org/record/576615
Almost sure convergence of randomly truncated stochastic algorithms under verifiable conditions
Creators: name: Lelong, Jérôme
Publisher: name: arXiv
Year: 2007
Subjects: subject: Probability (math.PR)
subject: FOS: Mathematics
subject: 62L20, 62E29, 60F17

description: We study the almost sure convergence of randomly truncated stochastic algorithms. We present a new convergence theorem which extends the already known results by making vanish the classical condition on the noise terms. The aim of this work is to prove an almost sure convergence result of randomly truncated stochastic algorithms under easily verifiable conditions
Pseudo-3-Branes in a Curved 6D Bulk
Creators: name: Bogdanos, C.
name: Kehagias, A.
name: Tamvakis, K.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We consider a model involving a 4-brane in a 6D bulk which carries sigma model fields. An axion field on the 4-brane cancels the pressure along one direction leading to an effective codimension-2 3-brane. For a range of parameters of the theory, we get a transverse space which is non-compact, providing a possible solution to the cosmological constant problem. A setup with two branes in a compact space is also treated. In this case, a mild fine-tuning between the radii of the two 4-branes is necessary. Finally, we explore the 4-brane problem in the Gauss-Codazzi formulation and we discuss general aspects of gravity in the presence of additional brane sources.
description: 13 pages
Nisitrus marginatus Walker 1869
Creators: name: Tan, Ming Kai
name: Wahab, Rodzay bin Haji Abdul
name: Japir, Razy
name: Chung, Authur Y. C.
name: Robillard, Tony
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Orthoptera
Gryllidae
Nisitrus
Nisitrus marginatus

description: Nisitrus marginatus Walker, 1869 junior synonym of Nisitrus vittatus (Haan, 1944), syn. reinstated Table 2
Nisitra marginata Walker, 1869: 92.
Nisitrus vittatus – Saussure 1878: 653. — Chopard 1968: 352.
Nisitra vittata – Kirby 1906; 87 (junior synonym).
Nisitrus marginatus – Otte 1994: 67 (name reinstated). — Cigliano et al. 2020 (Orthoptera species File Online).
Material examined
Syntype
INDONESIA – Sumatra • 1 ♀; Stamford Raffles leg.; NHMUK 012497570.
Remarks
It is unclear why Otte (1994) reinstated N. marginatus as a valid species, even though earlier literature had already synonymised this species under N. vittatus. Based on the observation of a female syntype showing no difference with N. vittatus, we synonymise N. marginatus again under N. vittatus.
description: Published as part of Tan, Ming Kai, Wahab, Rodzay bin Haji Abdul, Japir, Razy, Chung, Authur Y. C. & Robillard, Tony, 2021, Revision of the cricket genus Nisitrus Saussure (Orthoptera: Gryllidae: Eneopterinae) and descriptions of five new species, pp. 1-75 in European Journal of Taxonomy 761 (1) on page 57, DOI: 10.5852/ejt.2021.761.1449, http://zenodo.org/record/5156259
Dynamical correlations and collective excitations of Yukawa liquids
Creators: name: Donko, Zoltan
name: Kalman, Gabor J.
name: Hartmann, Peter
Publisher: name: arXiv
Year: 2008
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: Computational Physics (physics.comp-ph)
subject: FOS: Physical sciences

description: In dusty (complex) plasmas, containing mesoscopic charged grains, the grain-grain interaction in many cases can be well described through a Yukawa potential. In this Review we summarize the basics of the computational and theoretical approaches capable of describing many-particle Yukawa systems in the liquid and solid phases and discuss the properties of the dynamical density and current correlation spectra of three- and two-dimensional strongly coupled Yukawa systems, generated by molecular dynamics simulations. We show details of the $ω(k)$ dispersion relations for the collective excitations in these systems, as obtained theoretically following the quasilocalized charge approximation, as well as from the fluctuation spectra created by simulations. The theoretical and simulation results are also compared with those obtained in complex plasma experiments.
description: 54 pages, 31 figures
Sub-10ps Monolithic and Low-power Photodetector Readout
Creators: name: Varner, Gary S.
name: Ruckman, Larry L.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Instrumentation and Detectors (physics.ins-det)
subject: Accelerator Physics (physics.acc-ph)
subject: FOS: Physical sciences

description: Recent advances in photon detectors have resulted in high-density imaging arrays that offer many performance and cost advantages. In particular, the excellent transit time spread of certain devices show promise to provide tangible benefits in applications such as Positron Emission Tomography (PET). Meanwhile, high-density, high-performance readout techniques have not kept on pace for exploiting these developments. Photodetector readout for next generation high event rate particle identification and time-resolved PET requires a highly-integrated, low-power, and cost-effective readout technique. We propose fast waveform sampling as a method that meets these criteria and demonstrate that sub-10ps resolution can be obtained for an existing device.
description: 12 pages, 20 figures, submitted to NIM A
MUDANÇAS CLIMÁTICAS E AMBIENTAIS NO NORDESTE DO BRASIL DO DEGLACIAL AO MEGHALAYAN
Creators: name: Utida, Giselle
name: Cruz, Francisco W.
name: Santos, Roberto V.
name: Sawakuchi, Andre O.
name: Wang, Hong
name: Pessenda, Luiz C.R.
name: Novello, Valdir F.
name: Vuille, Mathias
name: Strauss, André M.
name: Borella, Ana C.
name: Strikis, Nikolas M
name: Guedes, Carlos C. F.
name: Andrade, Fabio R. D.
name: Zhang, Haiwei
name: Cheng, Hai
name: Edwards, R. Lawrence
Publisher: name: Zenodo
Year: 2020
Subjects: isótopos estáveis
espeleotemas
ZCTI
arqueologia
impactos demográficos

description: Mudanças na insolação causadas pela precessão e obliquidade são consideradas o principal motor da precipitação tropical em escalas de tempo orbitais, responsáveis pelas mudanças na vegetação e na paisagem física durante o Holoceno Tardio na América do Sul. Tais mudanças foram investigadas na região cárstica da Chapada do Apodi – RN, Nordeste do Brasil (NEB), usando uma abordagem multiproxy com análises isotópicas de carbono ( 13C), oxigênio ( 18O) e estrôncio (87Sr/86Sr) em espeleotemas de diferentes cavernas, rocha carbonática encaixante e nos depósitos sedimentares das cavernas. Os resultados revelam que o equilíbrio entre a formação e erosão do solo, os impactos sobre a vegetação e as alterações na precipitação ocorreram em resposta às variações na posição e intensidade da Zona de Convergência Intertropical desde o deglacial, associadas à variabilidade da insolação. Valores enriquecidos de  13C e  18O e empobrecidos de 87Sr/86Sr em torno de 4.200 anos BP indicam um episódio maciço de erosão do solo, resultando na exposição de rochas carbonáticas sobre uma grande área do terreno cárstico. Esse evento marca o início da cronozona Meghalayan, caracterizada pela aridificação da região, declínio da produção do solo, extinção das drenagens subterrâneas e aumento da dominância de espécies da caatinga. Essas mudanças do Holoceno foram comparadas a densidade demográfica no NEB, inferidas a partir de idades de radiocarbono calibradas. Os resultados demonstram que o curso demográfico geral é similar à curva estabelecida para toda a América do Sul, caracterizada pela deflação da população durante o Holoceno Médio e crescimento durante o Holoceno Tardio, não correspondendo aos eventos ambientais e climáticos registrados. Estes resultados foram publicados online em 22 de outubro de 2020 na revista Quaternary Science Reviews (250, 106655, doi: 10.1016/j.quascirev.2020.106655).
Premicellar aggregation of amphiphilic molecules: Aggregate lifetime and polydispersity
Creators: name: Hadgiivanova, Radina
name: Diamant, Haim
Publisher: name: arXiv
Year: 2008
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: A recently introduced thermodynamic model of amphiphilic molecules in solution has yielded, under certain realistic conditions, a significant presence of metastable aggregates well below the critical micelle concentration -- a phenomenon that has been reported also experimentally. The theory is extended in two directions pertaining to the experimental and technological relevance of such premicellar aggregates. (a) Combining the thermodynamic model with reaction rate theory, we calculate the lifetime of the metastable aggregates. (b) Aggregation number fluctuations are examined. We demonstrate that, over most of the metastable concentration range, the premicellar aggregates should have macroscopic lifetimes and small polydispersity.
description: 7 pages, 2 figures
On resonant generation of electromagnetic modes in nonlinear electrodynamics: Classical approach
Creators: name: Kopchinskii, Ilia
name: Satunin, Petr
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: The paper explores a theoretical possibility of resonant amplification of electromagnetic modes generated by a nonlinear effect in Euler-Heisenberg electrodynamics. Precisely, we examine the possibility of the amplification for the third harmonics induced by a single electromagnetic mode in radiofrequency cavity, as well as the generation of signal mode of combined frequencies induced by two pump modes ($ω_1$ and $ω_2$) in the cavity. Solving inhomogeneous wave equations for the signal mode, we formulate two resonant conditions for a cavity of arbitrary shape, and apply the obtained formalism to linear and rectangular cavities. We explicitly show that the third harmonics as well as the mode of combined frequency $2ω_1 + ω_2$ are not resonantly amplified while the signal mode with frequency $2ω_1 - ω_2$ is amplified for a certain cavity geometry.
description: 10 pages, 5 tables
On spin 3 interacting with gravity
Creators: name: Zinoviev, Yu. M.
Publisher: name: arXiv
Year: 2008
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Recently Boulanger and Leclercq have constructed cubic four derivative $3-3-2$ vertex for interaction of spin 3 and spin 2 particles. This vertex is trivially invariant under the gauge transformations of spin 2 field, so it seemed that it could be expressed in terms of (linearized) Riemann tensor. And indeed in this paper we managed to reproduce this vertex in the form $R \partial Φ\partial Φ$, where $R$ -- linearized Riemann tensor and $Φ$ -- completely symmetric third rank tensor. Then we consider deformation of this vertex to $(A)dS$ space and show that such deformation produce "standard" gravitational interaction for spin 3 particles (in linear approximation) in agreement with general construction of Fradkin and Vasiliev. Then we turn to the massive case and show that the same higher derivative terms allows one to extend gauge invariant description of massive spin 3 particle from constant curvature spaces to arbitrary gravitational backgrounds satisfying $R_{μν} = 0$.
description: 11 pages, no figures. Some comments and new references added
How Efficient is Rotational Mixing in Massive Stars ?
Creators: name: Brott, I.
name: Hunter, I.
name: Anders, P.
name: Langer, N.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The VLT-Flames Survey for Massive Stars (Evans05,Evans06) provides recise measurements of rotational velocities and nitrogen surface abundances of massive stars in the Magellanic Clouds. Specifically, for the first time, such abundances have been estimated for stars with significant rotational velocities. This extraordinary data set gives us the unique possibility to calibrate rotationally and magnetically induced mixing processes. Therefore, we have computed a grid of stellar evolution models varying in mass, initial rotational velocity and chemical composition. In our models we find that although magnetic fields generated by the Spruit-Taylor dynamo are essential to understand the internal angular momentum transport (and hence the rotational behavior), the corresponding chemical mixing must be neglected to reproduce the observations. Further we show that for low metallicities detailed initial abundances are of prime importance, as solar-scaled abundances may result in significant calibration errors.
description: To appear in the proceedings of "First Stars III", Santa Fe, New Mexico, July 16-20, 2007, 3 pages, 3 figures
The effects of annular and conical inhomogeneities upon the central-axis scatter dose in a cobalt 60 photon beam
Creators: name: McParland, Brian James
Publisher: name: University of British Columbia
Year: 2010

description: Tissue inhomogeneities can significantly alter the radiation dose delivered to a tumor. In the past, the accuracy of dose calculations has been limited by a lack of precise knowledge of the inhomogeneities within the patient's anatomy. Such anatomical information is now available in much greater detail due to the widespread use of computed tomography (CT) in radiotherapy treatment planning. Consequently, the potential for more accurate dosimetry has grown. The difficulty now resides iii being able to efficiently handle this CT data. The effect of an inhomogeneity upon the primary dose is well known. That upon the scatter is not. Therefore, we have limited our study to that of the alteration in the scatter dose. The perturbation is a complicated function of the density and position of the inhomogeneity, information which is available from CT data. A method, known as the differential Batho method, has been developed to estimate the scatter dose change. It provides a calculation of the effects due to an inhomogeneity in the shape of an annulus, or a cone's frustum, concentric about the central axis. This method allows the effects of multiple inhomogeneities to be estimated. Several series of experiments were performed to measure the effects of such inhomogeneities, in a ⁶⁰Co beam, as functions of density and geometry. It was found that for many of the geometries tested, the differential Batho method gave a good account of the changes measured. The deviations that occurred were readily accounted for. The differential Batho method provides a good measure of the scatter effects for simple symmetric geometries. In this thesis, it is recommended that further studies be made with phantoms simulating the human anatomy to test the method for specific treatment techniques.
Conformally Invariant "Massless" Spin-2 Field in de Sitter Universe
Creators: name: Dehghani, M.
name: Rouhani, S.
name: Takook, M. V.
name: Tanhayi, M. R.
Publisher: name: arXiv
Year: 2008
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: ''Massless'' spin-2 field equation in de Sitter space, which is invariant under the conformal transformation, has been obtained. The frame work utilized is the symmetric rank-2 tensor field of the conformal group. Our method is based on the group theoretical approach and six-cone formalism, initially introduced by Dirac. Dirac's six-cone is used to obtain conformally invariant equations on de Sitter space. The solution of the physical sector of massless spin-2 field (linear gravity) in de Sitter ambient space is written as a product of a generalized polarization tensor and a massless minimally coupled scalar field. Similar to the minimally coupled scalar field, for quantization of this sector, the Krein space quantization is utilized. We have calculated the physical part of the linear graviton two-point function. This two-point function is de Sitter invariant and free of pathological large distance behavior.
description: 22 pages
การปรับปรุงคุณภาพดินโดยใช้ยิปซัมเพื่อความยั่งยืนทางการเกษตร
Creators: name: นุจรินทร์  ศิรวาลย์
Publisher: name: มหาวิทยาลัยเกษตรศาสตร์
Year: 2011
Subjects: ยิปซัม, สารปรับปรุงดิน, ดินกรด, ดินเค็ม, การแน่นทึบของดิน

description: 1, 5, วารสารวิชาการและวิจัย มทร.พระนคร
Max-Min Ant System to Solve Vehicle Routing Problem Case Study: THANTIP Factory of Drinking Water
Creators: name: Suphan Sodsoon
name: Sombat Sindhuchao
Publisher: name: Faculty of Engineering, Khon Kaen Univeristy
Year: 2010
Subjects: Meta-heuristic,Max-Min Ant System, Vehicle routing problem

description: 2, 37, KKU Engineering Journal
Why does wurtzite form in nanowires of III-V zinc-blende semiconductors?
Creators: name: Glas, F.
name: Harmand, J. -C.
name: Patriarche, G.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: We develop a nucleation-based model to explain the formation of the wurtzite (WZ) crystalline phase during the vapor-liquid-solid growth of free-standing nanowires of zinc-blende (ZB) semiconductors. We first show that, in nanowires, nucleation generally occurs at the outer edge of the solid/liquid interface (the triple phase line) rather than elsewhere at the solid/liquid interface. In the present case, this entails major differences between ZB and WZ nuclei. Depending on the pertinent interface energies, WZ nucleation is favored at high liquid supersaturation. This explains our systematic observation of ZB during the early stages of nanowire growth.
description: 4 pages with 4 figures Submitted to Physical Review Letters
The ACS Survey of Galactic Globular Clusters. II. Stellar Evolution Tracks, Isochrones, Luminosity Functions, and Synthetic Horizontal-Branch Models
Creators: name: Dotter, A.
name: Chaboyer, B.
name: Jevremovic, D.
name: Baron, E.
name: Ferguson, J. W.
name: Sarajedini, A.
name: Anderson, J.
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The ACS Survey of Galactic Globular Clusters, an HST Treasury Project, will deliver high quality, homogeneous photometry of 65 globular clusters. This paper introduces a new collection of stellar evolution tracks and isochrones suitable for analyzing the ACS Survey data. Stellar evolution models were computed at [Fe/H]= -2.5, -2.0, -1.5, -1.0, -0.5, and 0; [alpha/Fe]= -0.2, 0, 0.2, 0.4, 0.6, and 0.8; and three initial He abundances for masses from 0.1 to 1.8 Msun and ages from 2 to 15 Gyr. Each isochrone spans a wide range in luminosity from Mv~14 up to the tip of the red giant branch. These are complemented by a set of He-burning tracks that extend from the zero age horizontal branch to the onset of thermal pulsations on the asymptotic giant branch. In addition, a set of computer programs are provided that make it possible to interpolate the isochrones in [Fe/H], generate luminosity functions from the isochrones, and create synthetic horizontal branch models. The tracks and isochrones have been converted to the observational plane with two different color-Teff transformations, one synthetic and one semi-empirical, in ground-based B, V, and I, and F606W and F814W for both ACS-WFC and WFPC2 systems. All models and programs presented in this paper are available from http://stellar.dartmouth.edu/~models/
description: 46 pages, 12 figures, AJ in press; figures 11 and 12 are reduced in size
Determining the metric of the Cosmos: stability, accuracy, and consistency
Creators: name: McClure, M. L.
name: Hellaby, Charles
Publisher: name: arXiv
Year: 2007
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: The ultimate application of Einstein's field equations is to empirically determine the geometry of the Universe from its matter content, rather than simply assuming the Universe can be represented by a homogeneous model on all scales. Choosing an LTB model as the most convenient inhomogeneous model for the early stages of development, a data reduction procedure was recently validated using perfect test data. Here we simulate observational uncertainties and improve the previous numerical scheme to ensure that it will be usable with real data as soon as observational surveys are sufficiently deep and complete. Two regions require special treatment--the origin and the maximum in the areal radius. To minimize numerical errors near the origin, we use an LTB series expansion to provide the initial values for integrating the differential equations. We also use an improved method to match the numerical integration to the series expansion that bridges the region near the maximum in the areal radius. Because the mass enclosed within the maximum obeys a specific relationship, we show that it is possible to correct for a fixed systematic error in either the distance scale or the redshift-space mass density, such that the integrated values are consistent with the data at the maximum.
description: Revision, 21 pages, 6 figures
Analytic perturbations and systematic bias in statistical modeling and inference
Creators: name: Filar, Jerzy A.
name: Hudson, Irene
name: Mathew, Thomas
name: Sinha, Bimal
Publisher: name: arXiv
Year: 2008
Subjects: subject: Statistics Theory (math.ST)
subject: FOS: Mathematics
subject: 15A99 (Primary) 62J99 (Secondary)

description: In this paper we provide a comprehensive study of statistical inference in linear and allied models which exhibit some analytic perturbations in their design and covariance matrices. We also indicate a few potential applications. In the theory of perturbations of linear operators it has been known for a long time that the so-called ``singular perturbations'' can have a big impact on solutions of equations involving these operators even when their size is small. It appears that so far the question of whether such undesirable phenomena can also occur in statistical models and their solutions has not been formally studied. The models considered in this article arise in the context of nonlinear models where a single parameter accounts for the nonlinearity.
description: Published in at http://dx.doi.org/10.1214/193940307000000022 the IMS Collections (http://www.imstat.org/publications/imscollections.htm) by the Institute of Mathematical Statistics (http://www.imstat.org)
A method for developing soil management units
Creators: name: Zweck Von Zweckenburg, Elizabeth Maria Erna
Publisher: name: University of British Columbia
Year: 2010

description: The purpose of the present study was to develop a quantitative methodology to define optimum land use systems. Soil survey data were assessed for capability, suitability and feasibility uses to establish interpretative soil units for which planning and management recommendations could be made. The study was agriculturally oriented due to the availability of agricultural productivity data for suitability assessments from four sources: farmer survey, direct estimate by expert consensus, research station data and plot trials-Soils were grouped using cluster analysis on the basis of permanent inherent soil properties. The technique did not group the soils satisfactorily for management purposes due to statistical limitations of the procedure in assessing overlapping and interdependent variables, such as soil characteristics, and restrictions imposed by the soils data set which was neither adequately large nor diverse to form multimember soil groups. Stepwise discriminant analysis was more successful in assessing the interpretative soils data and in identifying discriminant soil parameters. The Canada Land Inventory derived capability classes were separated by drainage, the quantitatively defined suitability classes were separated by parent material and the socioeconomically defined feasibility groups were separated by pH and coarse fraction. Comparison of the interpretative soils classifications revealed that the capability ratings overestimated actual measured yield and that current land use did not realize the full agricultural potential of the land. Feasibility, unlike capability and suitability, stressed parameters other than soil properties in land evaluation. The suitability assessment based upon actual observed productivity data measured under real market conditions was recommended as the most quantitative land evaluation approach. Other soils can be added to the open ended system and optimal use can be made of all soils using guidelines developed by key farmers under real market conditions for soils suitability groups.