cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Modeling of geochemical reactions with fluid flow simulation for scale precipitation and alkaline/surfactant/polymer flooding processes
Creators: name: Ozen, Emre
name: 0000-0002-0464-1126
Publisher: name: The University of Texas at Austin
Year: 2017
Subjects: Scale
Precipitation
Calcium carbonate
Barium sulfate
Temperature dependency
Relative permeability
UTCHEM
Geochemical reactions
Soap generation
pH
Surfactant adsorption

description: Precipitation of minerals is a very prevalent and crucial challenge that occurs once there are two different water phases (types), which consist of different concentration of elements, in a reservoir with changing environmental parameters such as temperature and pressure. Most operated oil and gas fields have been facing the problem of deposition of scales around and inside the wellbore since they have not only water injection but also water production. There is a lack of investigation about scale problem because of the uncomprehensive reservoir simulator considering scale precipitation during water injection and production. In this study, an in-house three-dimensional multi-phase reservoir simulator (UTCHEM) is used to model amount of scale precipitation for several cases. In this work, we neglect the effect of hydrocarbon (eg. CH₄, CO₂, and H₂S) dissolutions during scale deposition. Kinetic reactions are coupled with the fluid flow simulator to consider efficiency of water flooding process affected by scale precipitation around the injection and production wells. Several scale deposition and remediation mechanisms are investigated to tune reaction parameters against experimental data at reservoir condition to study transportation, deposition, and remediation of scales near wells. Simulation results show that ignoring scale precipitation in modeling leads to poor prediction for productivity and injectivity of water flood or another enhanced oil recovery (EOR) processes. Simulation study considering scale precipitation totally changes the performance of water flood and production scenarios. Results reveal that the composition of injected water, pH, and temperature of injected water are important factors that control the scale deposition. Meanwhile, these factors are essential to guide the scale remediation process near the wells. We also used the UTCHEM simulator to investigate the effect of temperature on geochemistry reactions during alkaline surfactant polymer (ASP) injection. Such process efficiency that rely on geochemistry reactions are depend on temperature. We also investigate two different relative permeability models in UTCHEM. A case of alkaline/surfactant polymer core flood is established to test this purpose as well as soap generation because of reaction between alkaline and acid components
Exactly solvable time-dependent non-Hermitian quantum systems from point transformations
Creators: name: Fring, Andreas
name: Tenney, Rebecca
Publisher: name: arXiv
Year: 2021
Subjects: subject: Quantum Physics (quant-ph)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: We demonstrate that complex point transformations can be used to construct non-Hermitian first integrals, time-dependent Dyson maps and metric operators for non-Hermitian quantum systems. Initially we identify a point transformation as a map from an exactly solvable time-independent system to an explicitly time-dependent non-Hermitian Hamiltonian system. Subsequently we employ the point transformation to construct the non-Hermitian time-dependent invariant for the latter system. Exploiting the fact that this invariant is pseudo-Hermitian, we construct a corresponding Dyson map as the adjoint action from a non-Hermitian to a Hermitian invariant, thus obtaining solutions to the time-dependent Dyson and time-dependent quasi-Hermiticity equation together with solutions to the corresponding time-dependent Schrödinger equation.
description: 18 pages
Verena Walter, Überleben von Kindern und Jugendlichen in den Konzentrationslagern Sachsenhausen, Auschwitz und Bergen-Belsen
Creators: name: Fober, Magdalena
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2012

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 61 Nr. 4 (2012)
Anna Maria Belardinelli, Giovanni Greco (a cura di) Antigone e le Antigoni. Storia forme fortuna di un mito. Atti del Convegno internazionale, Roma, 13, 25-26 Maggio 2009, Sapienza Università di Roma. Firenze. Le Monnier Università. 2010. pp. X+314
Creators: name: Baltieri, Nadia
Publisher: name: Annali Online  Lettere - Ferrara
Year: 2012

description: Annali Online  Lettere - Ferrara, VI 1-2 (2011)
Marian Rębkowski, Die Christianisierung Pommerns. Eine archäologische Studie
Creators: name: Mühle, Eduard
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2013

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 62 Nr. 4 (2013)
Jerzy Lukowski, Liberty`s folly. The Polish-Lihuanian commonwealth in the eighteenth century, 1697-1795
Creators: name: Hübner, Eckhard
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 1995

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 44 Nr. 3 (1995)
Christian Westerhoff, Zwangsarbeit im Ersten Weltkrieg. Deutsche Arbeitskräftepolitik im besetzten Polen und Litauen 1914-1918
Creators: name: Lehnstaedt, Stephan
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2012

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 61 Nr. 4 (2012)
Setting up a bioeconomy monitoring : sustainability – resources – products
Creators: name: Schweinle, Jörg
name: Banse, Martin
name: Barrelet, Johna
name: Brüning, Simone
name: Cyffka, Karl-Friedrich
name: Gordillo Vera, Fernando
name: Iost, Susanne
name: Kilian, David
name: Omidi Saravani, Faranak
name: Weimar, Holger
name: Wilske, Burkhard
Publisher: name: Unknown
Year: 2025
Subjects: subject: Research Research Methods/Statistical Methods
subject: Resource/Energy Economics and Policy
subject: bioeconomy
subject: material flow
subject: sustainability
subject: monitoring bio-based
subject: assessment

description: This Thünen Working Paper presents the results of the research project "Joint Project: Expansion of a systematic monitoring of the bioeconomy - consolidation phase." The project aimed to further develop the monitoring concept for the German bioeconomy and to update initial monitoring results. This Working Paper refers to the Thünen Working Paper 149 and presents updated monitoring results on the one hand, and approaches to the monitoring of substitution and the recording and tracking of import commodities and their sustainability effects on the other.
description: DOI:10.3220/253-2025-27
Harald Zschiedrich (Hrsg.), Wirtschaftliche Zusammenarbeit in Grenzregionen. Erwartungen - Bedingungen - Erfahrungen
Creators: name: Müller, Uwe
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2013

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 62 Nr. 4 (2013)
Eigenvalue bounds for polynomial central potentials in d dimensions
Creators: name: Katatbeh, Qutaibeh D.
name: Hall, Richard L.
name: Saad, Nasser
Publisher: name: arXiv
Year: 2007
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: If a single particle obeys non-relativistic QM in R^d and has the Hamiltonian H = - Delta + f(r), where f(r)=sum_{i = 1}^{k}a_ir^{q_i}, 2\leq q_i < q_{i+1}, a_i \geq 0$, then the eigenvalues E = E_{n\ell}^{(d)}(λ) are given approximately by the semi-classical expression E = \min_{r > 0}[\frac{1}{r^2} + \sum_{i = 1}^{k}a_i(P_ir)^{q_i}]. It is proved that this formula yields a lower bound if P_i = P_{n\ell}^{(d)}(q_1), an upper bound if $P_i = P_{n\ell}^{(d)}(q_k) and a general approximation formula if P_i = P_{n\ell}^{(d)}(q_i). For the quantum anharmonic oscillator f(r)=r^2+λr^{2m},m=2,3,... in d dimension, for example, E = E_{n\ell}^{(d)}(λ) is determined by the algebraic expression λ={1\over β}({2α(m-1)\over mE-δ})^m({4α\over (mE-δ)}-{E\over (m-1)}) where δ={\sqrt{E^2m^2-4α(m^2-1)}} and α, βare constants. An improved lower bound to the lowest eigenvalue in each angular-momentum subspace is also provided. A comparison with the recent results of Bhattacharya et al (Phys. Lett. A, 244 (1998) 9) and Dasgupta et al (J. Phys. A: Math. Theor., 40 (2007) 773) is discussed.
description: 13 pages, no figures
The tabulation of prime knot projections with their mirror images up to eight double points
Creators: name: Ito, Noboru
name: Takimura, Yusuke
Publisher: name: arXiv
Year: 2021
Subjects: subject: Geometric Topology (math.GT)
subject: FOS: Mathematics

description: This paper provides the complete table of prime knot projections with their mirror images, without redundancy, up to eight double points systematically thorough a finite procedure by flypes. In this paper, we show how to tabulate the knot projections up to eight double points by listing tangles with at most four double points by an approach with respect to rational tangles of J. H. Conway. In other words, for a given prime knot projection of an alternating knot, we show how to enumerate possible projections of the alternating knot. Also to tabulate knot projections up to ambient isotopy, we introduce arrow diagrams (oriented Gauss diagrams) of knot projections having no over/under information of each crossing, which were originally introduced as arrow diagrams of knot diagrams by M. Polyak and O. Viro. Each arrow diagram of a knot projection completely detects the difference between the knot projection and its mirror image.
description: 25 pages, 18 figures
Integral Transforms and Drinfeld Centers in Derived Algebraic Geometry
Creators: name: Ben-Zvi, David
name: Francis, John
name: Nadler, David
Publisher: name: arXiv
Year: 2008
Subjects: subject: Algebraic Geometry (math.AG)
subject: Algebraic Topology (math.AT)
subject: Representation Theory (math.RT)
subject: FOS: Mathematics

description: We study the interaction between geometric operations on stacks and algebraic operations on their categories of sheaves. We work in the general setting of derived algebraic geometry: our basic objects are derived stacks X and their oo-categories QC(X) of quasicoherent sheaves. We show that for a broad class of derived stacks, called perfect stacks, algebraic and geometric operations on their categories of sheaves are compatible. We identify the category of sheaves on a fiber product with the tensor product of the categories of sheaves on the factors. We also identify the category of sheaves on a fiber product with functors between the categories of sheaves on the factors (thus realizing functors as integral transforms, generalizing a theorem of Toen for ordinary schemes). As a first application, for a perfect stack X, consider QC(X) with its usual monoidal tensor product. Then our main results imply the equivalence of the Drinfeld center (or Hochschild cohomology category) of QC(X), the trace (or Hochschild homology category) of QC(X) and the category of sheaves on the loop space of X. More generally, we show that the E_n-center and the E_n-trace (or E_n-Hochschild cohomology and homology categories respectively) of QC(X) are equivalent to the category of sheaves on the space of maps from the n-sphere into X. This directly verifies geometric instances of the categorified Deligne and Kontsevich conjectures on the structure of Hochschild cohomology. As a second application, we use our main results to calculate the Drinfeld center of categories of linear endofunctors of categories of sheaves. This provides concrete applications to the structure of Hecke algebras in geometric representation theory. Finally, we explain how all of the above results can be interpreted in the context of topological field theory.
description: Final revised version, to appear, Jour. Amer. Math. Soc
Leszek Jarmiński, Bez użycia siły. Działalność polityczna protestantów w Rzeczypospolitej u schyłku XVI wieku
Creators: name: Hartmann, Stefan
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 1995

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 44 Nr. 3 (1995)
Johannes Frackowiak, Wanderer im nationalen Niemandsland. Polnische Ethnizität in Mitteldeutschland von 1880 bis zur Gegenwart
Creators: name: Krzoska, Markus
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2012

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 61 Nr. 4 (2012)
Heavy quark correlations in hadronic collisions
Creators: name: Luszczak, M.
name: Szczurek, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We discuss results of the $k_t$ - factorization approach for heavy quark-heavy antiquark correlations in proton-proton and proton-antiproton collisions for RHIC, Tevatron and LHC. We consider correlations in the azimuthal angle as well as in the two-dimensional space of transverse momentum of heavy quark and heavy antiquark. We compare results obtained with the help of different unintegrated parton distributions (UPDF) from the literature.
description: 8 pages, 20 figures, a talk presented at International Workshop on High-pT physics at LHC, Jyvaskyla, Finland, March 23-27 2007
The morpho-kinematical structure and chemical abundances of the complex planetary nebula NGC 1514
Creators: name: Aller, Alba
name: Vázquez, Roberto
name: Olguín, Lorenzo
name: Miranda, Luis Felipe
name: Ressler, Michael E.
Publisher: name: arXiv
Year: 2021
Subjects: subject: Solar and Stellar Astrophysics (astro-ph.SR)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We present high-resolution, long-slit optical spectra and images of the planetary nebula NGC1514. The position velocity maps of the [OIII] emission line reveal complex kinematics with multiple structures. A morpho-kinematical analysis suggests an inner shell, originally spherical and now distorted by several bubbles, and an attached outer shell. The two well-defined, mid-infrared rings of NGC1514 are not detected in our high-resolution, long-slit spectra, which prevented us from doing a kinematical analysis of them. Based exclusively on their morphology, we propose a barrel-like structure to explain the rings. Several ejection processes have been possibly involved in the formation of the nebula although a time sequence is difficult to establish with the current data. We also analyze intermediate-resolution, long-slit spectra with the goal of studying the physical parameters and chemical abundances of NGC1514. The nebular spectra reveal a moderate-excitation nebula with weak emission lines of [ArIII], [NeIII], HeI and HeII. No [NII] neither other low-excitation emission lines are detected. We found an electron temperature around 14000K in the gas and an electron density in the range of 2000 and 4000 cm$^{-3}$.
description: Accepted for publication in MNRAS. 12 pages, 8 figures, 3 tables
Clemens Vollnhals (Hrsg.), Jahre des Umbruchs. Friedliche Revolution in der DDR und Transition in Ostmitteleuropa
Creators: name: Zagańczyk-Neufeld, Agnieszka
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2013

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 62 Nr. 4 (2013)
Studies on the cell cycle in Paramecium tetraurelia
Creators: name: Rasmussen, Colin Dale
Publisher: name: University of British Columbia
Year: 2010

description: Several aspects o-f the cell cycle in Parameciurn were studied using the temperature-sensitive mutations cc1 and cc2, and the recessive gene mutation tamG. Cell cycle progression can be blocked by the cc1 defect up to 0.72 of the cell cycle. There was no progression through the cell cycle at the restrictive temperature, nor excess delay o-f cell division once cells were returned to permissive conditions. The cc1 defect also reversibly inhibits macronuclear DNA synthesis throughout the cell cycle. Macronuclear DNA synthesis is not required for cell division past 0.72 of the cell cycle. Downward regulation of cell mass was examined. Cell mass is regulated by the concerted action of two mechanisms. First, the rate of growth becomes limited by gene dosage when cell mass increases. Second, the cell cycle is shortened when initial cell mass is increased, at the expense of G1. Cells with an initial cell mass greater than 120% of normal initial mass have a cell cycle duration equal to the normal length of S + nuclear division. Both cell mass and parental DNA content influence the timing of DNA synthesis initiation. As initial cell mass increases, the length of G1 decreases. When initial cell mass exceeds the normal value at the start of S, DNA synthesis begins immediately after fission, without a G1 period. G1 DNA content has no effect on the timing of DNA synthesis initiation. However, cells with low parental DNA content appear to enter S phase earlier than cells with high parental DNA content. A simple computer simulation model has been developed which consistent with the experimental observations. The model is based the unstable inhibitor model of Yeas et al. <1945>.
Dynamics of Colloidal Cubes and Cuboids in Cylindrical Nanopores
Creators: name: Patti, Alessandro
name: Cuetos, Alejandro
Publisher: name: arXiv
Year: 2021
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: FOS: Physical sciences

description: Understanding how colloidal suspensions behave in confined environments has a striking relevance in practical applications. Despite the fact that the behaviour of colloids in the bulk is key to identify the main elements affecting their equilibrium and dynamics, it is only by studying their response under confinement that one can ponder the use of colloids in formulation technology. In particular, confining fluids of anisotropic particles in nanopores provides the opportunity to control their phase behaviour and stabilise a spectrum of morphologies that cannot form in the bulk. By properly selecting pore geometry, particle architecture and system packing, it is possible to tune thermodynamic, structural and dynamical properties for ad hoc applications. In the present contribution, we report Grand Canonical and Dynamic Monte Carlo simulations of suspensions of colloidal cubes and cuboids constrained into cylindrical nanopores of different size. We first study their phase behaviour, calculate the chemical potential vs density equation of state and characterise the effect of the pore walls on particle anchoring and layering. In particular, at large enough concentrations, we observe the formation of concentric nematic-like coronas of oblate or prolate particles surrounding an isotropic core, whose features resemble those typically detected in the bulk. We then analyse the main characteristics of their dynamics and discover that these are dramatically determined by the ability of particles to diffuse in the longitudinal and radial direction of the nanopore.
description: The following article has been accepted by Physics of Fluids
The Sp(1)-Kepler Problems
Creators: name: Meng, Guowu
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: Let $n\ge 2$ be a positive integer. To each irreducible representation $σ$ of $\mathrm{Sp}(1)$, an $\mathrm{Sp}(1)$-Kepler problem in dimension $(4n-3)$ is constructed and analyzed. This system is super integrable and when $n=2$ it is equivalent to a generalized MICZ-Kepler problem in dimension five. The dynamical symmetry group of this system is $\widetilde {\mathrm O}^*(4n)$ with the Hilbert space of bound states ${\mathscr H}(σ)$ being the unitary highest weight representation of $\widetilde {\mathrm {O}^*}(4n)$ with highest weight $$(\underbrace{-1, ..., -1}_{2n-1}, -(1+\barσ)),$$ which occurs at the right-most nontrivial reduction point in the Enright-Howe-Wallach classification diagram for the unitary highest weight modules. Here $\barσ$ is the highest weight of $σ$. Furthermore, it is shown that the correspondence $σ\leftrightarrow \mathscr H(σ)$ is the theta-correspondence for dual pair $(\mathrm{Sp}(1), \mathrm{O}^*(4n))\subseteq\mathrm{Sp}_{8n}(\mathbb R)$.
description: 14 pages, more details
Holocene lacustrine sedimentation in a small subalpine watershed in the Coast Mountains of British Columbia
Creators: name: Souch, Catherine Jane
Publisher: name: University of British Columbia
Year: 2010

description: The lake sediments of Gallie Pond, a subalpine lake which drains the Goat Meadows watershed, a drainage basin in the Coast Mountains of south western British Columbia, were investigated to determine sediment transfers operating over the Holocene Epoch. Samples were collected from the terrestrial deposits of the Goat Meadows watershed and twenty six cores were taken from the lake sediments of Gallie Pond. Physical, chemical and mineralogical analyses were conducted on the terrestrial and lake sediment samples in order to determine sediment depth, size range and variability of specific properties of the sediments. The results indicate that the Goat Meadows watershed has remained a relatively low energy erosional system over the Holocene Epoch. The lithostratigraphy of the sediments best records the development of the lake from initial conditions of flowing water, to a peat bog and subsequently to an oligotrophic lake; a transition which may be related to regional palaeoclimatic change. Sediment yield from the watershed over the Holocene Epoch has varied by one order of magnitude. The mean rate is one and two orders of magnitude lower than the contemporary data for the watershed and the Coast Mountains region respectively. The source area for the clastic sediment within the watershed has changed from poorly weathered till to pedogenic sources with time, while the lake's organic matter has remained primarily allochthonous in origin. In the context of regional palaeoenvironments this study indicates rapid paraglacial erosion of glacial sediment in the immediate postglacial completed by ca. 10,000 years B.P.; an early date for the hypsithermal neoglacial boundary ca. 6300 years B.P.; progressive cooling of the three post hypsithermal neoglacial intervals; and, increased aeolian activity over the latter part of the Holocene Epoch.
Compactifying 5d superconformal field theories to 3d
Creators: name: Sacchi, Matteo
name: Sela, Orr
name: Zafrir, Gabi
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Building on recent progress in the study of compactifications of $6d$ $(1,0)$ superconformal field theories (SCFTs) on Riemann surfaces to $4d$ $\mathcal{N}=1$ theories, we initiate a systematic study of compactifications of $5d$ $\mathcal{N}=1$ SCFTs on Riemann surfaces to $3d$ $\mathcal{N}=2$ theories. Specifically, we consider the compactification of the so-called rank 1 Seiberg $E_{N_f+1}$ SCFTs on tori and tubes with flux in their global symmetry, and put the resulting $3d$ theories to various consistency checks. These include matching the (usually enhanced) IR symmetry of the $3d$ theories with the one expected from the compactification, given by the commutant of the flux in the global symmetry of the corresponding $5d$ SCFT, and identifying the spectrum of operators and conformal manifolds predicted by the $5d$ picture. As the models we examine are in three dimensions, we encounter novel elements that are not present in compactifications to four dimensions, notably Chern-Simons terms and monopole superpotentials, that play an important role in our construction. The methods used in this paper can also be used for the compactification of any other $5d$ SCFT that has a deformation leading to a $5d$ gauge theory.
description: 85 pages, 16 figures
Hyperthreads in holographic spacetimes
Creators: name: Harper, Jonathan
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: We generalize bit threads to hyperthreads in the context of holographic spacetimes. We define a "$k$-thread" to be a hyperthread which connects $k$ different boundary regions and posit that it may be considered as a unit of $k$-party entanglement. Using this new object, we show that the contribution of hyperthreads to calculations of holographic entanglement entropy are generically finite. This is accomplished by constructing a surface whose area determines their maximum allowed contribution. We also identify surfaces whose area is proportional to the maximum number of $k$-threads, motivating a possible measure of multipartite entanglement. We use this to make connections to the current understanding of multipartite entanglement in holographic spacetimes.
description: 25 pages, 10 figures. v2: Added example of one-sided black hole. Published version
Perfect $DD^*$ molecular prediction matching the $T_{cc}$ observation at LHCb
Creators: name: Li, Ning
name: Sun, Zhi-Feng
name: Liu, Xiang
name: Zhu, Shi-Lin
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: High Energy Physics - Lattice (hep-lat)
subject: FOS: Physical sciences

description: In 2012, we investigated the possible molecular states composed of two charmed mesons [Phys.Rev. D 88, 114008 (2013), arXiv:1211.5007 [hep-ph](2012)]. The $D^*D$ system with the quantum numbers of $I(J^P)=0(1^+)$ was found to be a good candidate of the loosely bound molecular state. This state is very close to the $D^*D$ threshold with a binding energy around 0.47 MeV. This prediction was confirmed by the new LHCb observation of $T_{cc}^+$ [see Franz Muheim's talk at the European Physical Society conference on high energy physics 2021].
description: 2 pages, 2 figures
Vähemusrahvuste kultuurielu Eesti Vabariigis 1918-1940. Dokumente ja materjale
Creators: name: Hasselblatt, Cornelius
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 1996

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 45 Nr. 4 (1996)
Martin Sabrow (Hrsg.), 1989 und die Rolle der Gewalt
Creators: name: Zagańczyk-Neufeld, Agnieszka
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 2013

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 62 Nr. 4 (2013)
Production of antihydrogen at reduced magnetic field for anti-atom trapping
Creators: name: Andresen, G B
name: Bertsche, W
name: Boston, A
name: Bowe, P D
name: Cesar, C L
name: Chapman, S
name: Charlton, M
name: Chartier, M
name: Deutsch, A
name: Fajans, J
name: Fujiwara, M C
name: Funakoshi, R
name: Gill, D R
name: Gomberoff, K
name: Hangst, J S
name: Hayano, R S
name: Hydomako, R
name: Jenkins, M J
name: Jorgensen, L V
name: Kurchaninov, L
name: Madsen, N
name: Nolan, P
name: Olchanski, K
name: Olin, A
name: Page, R D
name: Povilus, A
name: Robicheaux, F
name: Sarid, E
name: Silveira, D M
name: Storey, J W
name: Thompson, R I
name: van derWerf, D P
name: Wurtele, J S
name: Yamazaki, Y
Publisher: name: arXiv
Year: 2008
Subjects: subject: Nuclear Experiment (nucl-ex)
subject: FOS: Physical sciences

description: We have demonstrated production of antihydrogen in a 1$,$T solenoidal magnetic field. This field strength is significantly smaller than that used in the first generation experiments ATHENA (3$,$T) and ATRAP (5$,$T). The motivation for using a smaller magnetic field is to facilitate trapping of antihydrogen atoms in a neutral atom trap surrounding the production region. We report the results of measurements with the ALPHA (Antihydrogen Laser PHysics Apparatus) device, which can capture and cool antiprotons at 3$,$T, and then mix the antiprotons with positrons at 1$,$T. We infer antihydrogen production from the time structure of antiproton annihilations during mixing, using mixing with heated positrons as the null experiment, as demonstrated in ATHENA. Implications for antihydrogen trapping are discussed.
Criterion for testing the covariance of physical laws and Gordon optical metric
Creators: name: Wang, Changbiao
Publisher: name: arXiv
Year: 2021
Subjects: subject: General Physics (physics.gen-ph)
subject: FOS: Physical sciences
subject: 83, 78A25

description: The problem of covariance of physical quantities has not been solved fundamentally in the theory of relativity, which has caused a lot of confusion in the community; a typical example is the Gordon metric tensor, which was developed almost a century ago, and has been widely used to describe the equivalent gravitational effect of moving media on light propagation, predicting a novel physics of optical black hole. In this paper, it is shown that under Lorentz transformation, a covariant tensor satisfies three rules: (1) the tensor keeps invariant in mathematical form in all inertial frames; (2) all elements of the tensor have the same physical definitions in all frames; (3) the tensor expression in one inertial frame does not include any physical quantities defined in other frames. The three rules constitute a criterion for testing the covariance of physical laws, required by Einstein's principle of relativity. Gordon metric does not satisfy Rule (3), and its covariance cannot be identified before a general refractive index is defined. Finally, it is also shown as well that in the relativistic quantum mechanics, the Lorentz covariance of Dirac wave equation is not compatible with Einstein's mass-energy equivalence.
description: A minor-revised version published in Optik. 4 pages, no figures. To help reading, Impact Statement is attached. arXiv admin note: substantial text overlap with arXiv:1702.03200
Adaptive rewiring of random neural networks generates convergent-divergent units
Creators: name: Rentzeperis, Ilias
name: Laquitaine, Steeve
name: van Leeuwen, Cees
Publisher: name: arXiv
Year: 2021
Subjects: subject: Neurons and Cognition (q-bio.NC)
subject: FOS: Biological sciences
subject: 05C90

description: Brain networks are adaptively rewired continually, adjusting their topology to bring about functionality and efficiency in sensory, motor and cognitive tasks. In model neural network architectures, adaptive rewiring generates complex, brain-like topologies. Present models, however, cannot account for the emergence of complex directed connectivity structures. We tested a biologically plausible model of adaptive rewiring in directed networks, based on two algorithms widely used in distributed computing: advection and consensus. When both are used in combination as rewiring criteria, adaptive rewiring shortens path length and enhances connectivity. When keeping a balance between advection and consensus, adaptive rewiring produces convergent-divergent units consisting of convergent hub nodes, which collect inputs from pools of sparsely connected, or local, nodes and project them via densely interconnected processing nodes onto divergent hubs that broadcast output back to the local pools. Convergent-divergent units operate within and between sensory, motor, and cognitive brain regions as their connective core, mediating context-sensitivity to local network units. By showing how these structures emerge spontaneously in directed networks models, adaptive rewiring offers self-organization as a principle for efficient information propagation and integration in the brain.
Malgasyaptera reichli , Heiss 1998
Creators: name: Heiss, Ernst
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Hemiptera
Aradidae
Malgasyaptera
Malgasyaptera reichli

description: Malgasyaptera reichli, Heiss, 1998
Malgasyaptera reichli Heiss, 1998: 579. HT 3: Madagascar (Maromizah S Andasibe); CEHI.
Distr.: Madagascar
Ref.: Heiss, 1998b (fig., gen.)
description: Published as part of Heiss, Ernst, 2012, Annotated catalogue of the flat bug family Aradidae Brullé, 1836 of Madagascar and adjacent islands (Hemiptera: Heteroptera), pp. 45-63 in Zootaxa 3426 (1) on pages 49-50, DOI: 10.11646/zootaxa.3426.1.3, http://zenodo.org/record/214110
Piotr Górecki, Parishes, Tithes, and Society in Earlier Medieval Poland c. 1100-c.1250
Creators: name: Irgang, Winfried
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 1995

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 44 Nr. 3 (1995)
Sorting OAM modes with metasurfaces based on raytracing improved optical coordinate transformation
Creators: name: Liu, Zhibing
name: Zou, Jiahui
name: Lai, Zhaoyu
name: Tu, Jiajing
name: Gao, Shecheng
name: Liu, Weiping
name: Li, Zhaohui
Publisher: name: arXiv
Year: 2021
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: Optical coordinate transformation (OCT) has attracted widespread attention in the field of orbital angular momentum (OAM) (de)multiplexing or manipulation, but the performance of OCT would suffer from its distortion. In this paper, we quantitatively analyze the distortion of OCT from the perspective of ray optics, and explain its rationality to work under non-normal incident light. For the special case of log-polar coordinate transformation (LPCT), we use a raytracing assisted optimization scheme to improve its distortion, which is related to a Zernike polynomial based phase compensation. After raytracing optimization, the root mean square error (RMSE) of the focused rays is reduced to 1/5 of the original value and the physical optic simulation also shows great improvement. In the experiment, we use three phase masks which are realized by metasurfaces, the measured results show well consistency with the simulation. Results in this paper have great potential to improve the performance of OCT related applications.
description: 10 pages, 5 figues, submitted to optics express
The Stellar-Disk Electric (Short) Circuit: Observational Predictions for a YSO Jet Flow
Creators: name: Liffman, Kurt
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We discuss the star-disk electric circuit for a young stellar object (YSO) and calculate the expected torques on the star and the disk. We obtain the same disk magnetic field and star-disk torques as given by standard magnetohydrodynamic (MHD) analysis. We show how a short circuit in the star-disk electric circuit may produce a magnetically-driven jet flow from the inner edge of a disk surrounding a young star. An unsteady bipolar jet flow is produced that flows perpendicular to the disk plane. Jet speeds of order hundreds of kilometres per second are possible, while the outflow mass loss rate is proportional to the mass accretion rate and is a function of the disk inner radius relative to the disk co-rotation radius.
description: 6 pages, 8 figures, Accepted for publication in Astrophysics & Space Science
GHZ and W Entanglement Witnesses for the Non-interacting Fermi gas
Creators: name: Habibian, Hessam
name: Clark, John W.
name: Behbood, Naeimeh
name: Hingerl, Kurt
Publisher: name: arXiv
Year: 2008
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: The existence and nature of tripartite entanglement of a noninteracting Fermi gas (NIFG) is investigated. Three new classes of parameterized entanglement witnesses (EWs) are introduced with the aim of detecting genuine tripartite entanglement in the three-body reduced density matrix and discriminating between the presence of the two types of genuine tripartite entanglement, W\B and GHZ\W. By choosing appropriate EW operators, the problem of finding GHZ and W EWs is reduced to linear programming. Specifically, we devise new W EWs based on a spin-chain model with periodic boundary conditions, and we construct a class of parametrized GHZ EWs by linearly combining projection operators corresponding to all the different state-vector types arising for a three-fermion system. A third class of EWs is provided by a GHZ stabilizer operator capable of distinguishing W\B from GHZ\B entanglement, which is not possible with $W$ EWs. Implementing these classes of EWs, it is found that all states containing genuine tripartite entanglement are of W type, and hence states containing GHZ\W genuine tripartite entanglement do not arise. Some genuine tripartite entangled states that have a positive partial transpose (PPT) with respect to some bipartition are detected. Finally, it is demonstrated that a NIFG does not exhibit "pure" W\B genuine tripartite entanglement: three-party entanglement without any separable or biseparable admixture does not occur.
description: 15 pages, 7 figures, minor changes, to appear in Physical Review A
Radio constraint on outflows from tidal disruption events
Creators: name: Matsumoto, Tatsuya
name: Piran, Tsvi
Publisher: name: arXiv
Year: 2021
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Radio flares from tidal disruption events (TDEs) are generally interpreted as synchrotron emission arising from the interaction of an outflow with the surrounding circumnuclear medium (CNM). We generalize the common equipartition analysis to be applicable in cases lacking a clear spectral peak or even with just an upper limit. We show that, for detected events, there is a lower limit on the combination of the outflow's velocity $v$ and solid angle $Ω$, $\simeq vΩ^{a}$ (with $a \simeq 0.5$) that constrains the outflow's properties. Considering several possible outflow components accompanying TDEs, we find that: Isotropic outflows such as disk winds with $v\sim10^4\,\rm km\,s^{-1}$ and $Ω= 4 π$ can easily produces the observed flares; The bow shock of the unbound debris has a wedge-like geometry and it must be geometrically thick with $Ω\gtrsim1$ and a fraction of its mass ($\gtrsim 0.01 \,M_{\odot}$), has to move at $v \gtrsim 2 \times 10^4\,\rm km\,s^{-1}$; Conical Newtonian outflows such as jets can also be a radio source but both their velocity and the CNM density should be larger than those of isotropic winds by a factor of $\sim(Ω/4π)^{-0.5}$. Our limits on the CNM densities are typically 30-100 times larger than those found by previous analysis that ignored non-relativistic electrons that do not emit synchrotron radiation. We show that unless $v$ and $Ω$ are known radio observation alone cannot determine the CNM density. We also find that late (a few years after the TDE) radio upper-limits rule out energetic, $\sim 10^{51-52}\,\rm erg$, relativistic jets like the one observed in TDE Sw J1644+57, implying that such jets are rare.
description: 16 pages, 10 figures, 2 tables, accepted for publication in MNRAS
Measurement of filling factor 5/2 quasiparticle interference: observation of charge e/4 and e/2 period oscillations
Creators: name: Willett, R. L.
name: Pfeiffer, L. N.
name: West, K. W.
Publisher: name: arXiv
Year: 2008
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: A standing problem in low dimensional electron systems is the nature of the 5/2 fractional quantum Hall state: its elementary excitations are a focus for both elucidating the state's properties and as candidates in methods to perform topological quantum computation. Interferometric devices may be employed to manipulate and measure quantum Hall edge excitations. Here we use a small area edge state interferometer designed to observe quasiparticle interference effects. Oscillations consistent in detail with the Aharanov-Bohm effect are observed for integer and fractional quantum Hall states (filling factors 2, 5/3, and 7/3) with periods corresponding to their respective charges and magnetic field positions. With these as charge calibrations, at 5/2 filling factor and at lowest temperatures periodic transmission through the device consistent with quasiparticle charge e/4 is observed. The principal finding of this work is that in addtion to these e/4 oscillations, periodic structures corresponding to e/2 are also observed at 5/2 and at lowest temperatures. Properties of the e/4 and e/2 oscillations are examined with the device sensitivity sufficient to observe temperature evolution of the 5/2 quasiparticle interference. In the model of quasiparticle interference, this presence of an effective e/2 period may empirically reflect an e/2 quasiparticle charge, or may reflect multiple passes of the e/4 quasiparticle around the interferometer. These results are discussed within a picture of e/4 quasiparticle excitations potentially possessing non-Abelian statistics. These studies demonstrate the capacity to perform interferometry on 5/2 excitations and reveal properties important for understanding this state and its excitations.
description: version 3 contains additional data beyond version 2, 26 pages, 8 figures PNAS 0812599106
Constraints on sigma_8 from galaxy clustering in N-body simulations and semi-analytic models
Creators: name: Harker, Geraint
name: Cole, Shaun
name: Jenkins, Adrian
Publisher: name: arXiv
Year: 2007
Subjects: subject: Astrophysics (astro-ph)
subject: FOS: Physical sciences

description: We generate mock galaxy catalogues for a grid of different cosmologies, using rescaled N-body simulations in tandem with a semi-analytic model run using consistent parameters. Because we predict the galaxy bias, rather than fitting it as a nuisance parameter, we obtain an almost pure constraint on sigma_8 by comparing the projected two-point correlation function we obtain to that from the SDSS. A systematic error arises because different semi-analytic modelling assumptions allow us to fit the r-band luminosity function equally well. Combining our estimate of the error from this source with the statistical error, we find sigma_8=0.97 +/- 0.06. We obtain consistent results if we use galaxy samples with a different magnitude threshold, or if we select galaxies by b_J-band rather than r-band luminosity and compare to data from the 2dFGRS. Our estimate for sigma_8 is higher than that obtained for other analyses of galaxy data alone, and we attempt to find the source of this difference. We note that in any case, galaxy clustering data provide a very stringent constraint on galaxy formation models.
description: 14 pages, 8 figures; accepted by MNRAS
Observations of cold gas and star formation in dwarf S0 galaxies
Creators: name: Ge, Xue
name: Gu, Qiu-Sheng
name: Garcıa-Benito, Ruben
name: Lu, Shi-Ying
name: Lei, Cheng-Long
name: Ding, Nan
Publisher: name: arXiv
Year: 2021
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Very little work has been done on star formation in dwarf lenticular galaxies (S0s). We present 2D-spectroscopic and millimetre observations made by Centro Astronomico Hispano Aleman (CAHA) 3.5 m optical and the IRAM-30 m millimetre telescopes, respectively, for a sample of four dwarf S0 galaxies with multiple star formation regions in the field environment. We find that although most of the sources deviate from the star forming main sequence relation, they all follow the Kennicutt-Schmidt law. After comparing the stellar and Halpha kinematics, we find that the velocity fields of both stars and ionized gas do not show regular motion and the velocity dispersions of stars and ionized gas are low in the regions with high star formation, suggesting these star-forming S0 galaxies still have significant rotation. This view can be supported by the result that most of these dwarf S0 galaxies are classified as fast rotators. The ratio of average atomic gas mass to stellar mass (~ 47%) is much greater than that of molecular gas mass to stellar mass (~ 1%). In addition, the gas-phase metallicities in the star-forming regions are lower than that of the non-star-forming regions. These results indicate that the extended star formation may originate from the combination of abundant atomic hydrogen, long dynamic time scale and low-density environment.
description: 13 pages, 11 figures, Accepted by MNRAS
Photon-jet correlations in hadronic collisions
Creators: name: Pietrycki, T.
name: Szczurek, A.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: We compare results of $k_t$-factorization approach and next-to-leading order collinear-factorization approach for photon-jet correlations in $pp$ and $p \bar p$ collisions at RHIC, Tevatron and LHC energies. We discuss correlations in azimuthal angle as well as in two-dimensional space of transverse momenta of photon and jet. Different unintegrated parton distributions (UPDF) are included in the $k_t$-factorization approach. The results depend on UPDFs used. The results of NLO collinear-factorization are shown for comparison.
description: 7 pages, 12 figures, a talk presented at International Workshop on High-pT physics at LHC, Jyvaskyla, Finland, March 23-27 2007
Possible solution of the J/psi production puzzle
Creators: name: Haberzettl, H.
name: Lansberg, J. P.
Publisher: name: arXiv
Year: 2007
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Experiment (hep-ex)
subject: Nuclear Theory (nucl-th)
subject: FOS: Physical sciences

description: We argue that the s-channel cut contribution to J/psi hadroproduction can be significantly larger than the usual cut contribution of the color-singlet mechanism, which is known to underestimate the experimental measurements. A scenario accounting for intermediate $c\bar(c)$ interactions is proposed that reproduces the data at low- and mid-range transverse momenta P_T from the Fermilab Tevatron and BNL Relativistiv Heavy Ion Collider. The J/psi produced in this manner are polarized predominantly longitudinally.
description: 4 pages, 4 figures; version (with minor text revisions) as published in PRL
Die Revaler Munster-Rolle anno 1688. Ein Verzeichnis der Bürger und Einwohner
Creators: name: Kenéz, Csaba János
Publisher: name: Zeitschrift für Ostmitteleuropa-Forschung
Year: 1996

description: Zeitschrift für Ostmitteleuropa-Forschung, Bd. 45 Nr. 4 (1996)
Singular Solutions of Hessian Fully Nonlinear Elliptic Equations
Creators: name: Nadirashvili, Nikolai
name: Vladuts, Serge
Publisher: name: arXiv
Year: 2008
Subjects: subject: Analysis of PDEs (math.AP)
subject: Differential Geometry (math.DG)
subject: FOS: Mathematics
subject: 35J60

description: We study Hessian fully nonlinear uniformly elliptic equations and show that the second derivatives of viscosity solutions of those equations (in 12 or more dimensions) can blow up in an interior point of the domain. We prove that the optimal interior regularity of such solutions is no more than C^{1+ε}, showing the optimality of the known interior regularity result. The same is proven for Isaacs equations. We prove the existence of non-smooth solutions to fully nonlinear Hessian uniformly elliptic equations in 11 dimensions. We study also the possible singularity of solutions of Hessian equations defined in a neighborhood of a point and prove that a homogeneous order 0
description: 27 pages, submitted, two sections added