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Ab initio calculations of the isotopic dependence of nuclear clustering

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arXiv 2017年

作者： Elhatisari, Serdar Epelbaum, Evgeny Krebs, Hermann Lähde, Timo A. Lee, dean Li, Ning Lu, Bing-nan Meißner, Ulf-G rupak, Gautam Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universität Bonn BonnD-53115 Germany Department of Physics Karamanoglu Mehmetbey University Karaman70100 Turkey Institut für Theoretische Physik II Ruhr-Universität Bochum BochumD-44870 Germany Kavli Institute for Theoretical Physics University of California Santa BarbaraCA93106-4030 United States Institute for Advanced Simulation Institut für Kernphysik Jülich Center for Hadron Physics Forschungszentrum Jülich JülichD-52425 Germany National Superconducting Cyclotron Laboratory Michigan State University MI48824 United States Department of Physics North Carolina State University RaleighNC27695 United States JARA - High Performance Computing Forschungszentrum Jülich JülichD-52425 Germany Department of Physics and Astronomy HPC2 Center for Computational Sciences Mississippi State University Mississippi StateMS39762 United States

Nuclear clustering describes the appearance of structures resembling smaller nuclei such as alpha particles (4He nuclei) within the interior of a larger nucleus. While clustering is important for several well-known examples [1–4], much remains to be discovered about the general nature of clustering in nuclei. In this letter we present lattice Monte Carlo calculations based on chiral effective field theory for the ground states of helium, beryllium, carbon, and oxygen isotopes. By computing model-independent measures that probe three- and four-nucleon correlations at short distances, we determine the shape of the alpha clusters and the entanglement of nucleons comprising each alpha cluster with the outside medium. We also introduce a new computational approach called the pinhole algorithm, which solves a long-standing deficiency of auxiliary-field Monte Carlo simulations in computing density correlations relative to the center of mass. We use the pinhole algorithm to determine the proton and neutron density distributions and the geometry of cluster correlations in 12C, 14C, and 16C. The structural similarities among the carbon isotopes suggest that 14C and 16C have excitations analogous to the well-known Hoyle state resonance in 12C [5, 6]. Copyright © 2017, The Authors. All rights reserved.

关键词： Ground state

Charge-symmetry breaking in light hypernuclei based on chiral and similarity renormalization group-evolved interactions

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AIP Conference Proceedings 2019年第1期2130卷

作者： Andreas Nogga 1Institut für Kernphysik Institute for Advanced Simulation and Jülich Center for Hadron Physics Forschungszentrum Jülich D-52425 Jülich Germany 2JARA-High Performance Computing Forschungszentrum Jülich D-52425 Jülich Germany

We present Λ separation energies for light hypernuclei based on chiral hyperon-nucleon interactions at leading and next-to-leading order. For the very light systems, the problem can be directly solved using Faddeev-Yakubovsky equations. For systems with A > 4, we employ the Jacobi no-core shell model. In this case, the hyperon-nucleon and nucleon-nucleon interactions are evolved using the similarity renormalization group (SrG). We discuss the SrG parameter dependence in some detail. The results are used to study the charge-symmetry breaking of A = 4 and 6 hypernuclei.

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Variation of Uncertainty of drainage density in Flood Hazard Mapping Assessment with Coupled 1d-2d Hydrodynamics Model

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Research Square

research Square 2021年

作者： Yang, Song-Yue Chang, Che-Hao Hsu, Chih-Tsung Wu, Shiang-Jen Department of Urban Planning and Spatial Information Feng Chia University No.100 Wenhwa Rd. Seatwen Dist. Taichung40724 Taiwan Department of Civil Engineering National Taipei University of Technology No. 1 Sec. 3 Zhongxiao E. Rd. Taipei10608 Taiwan National Center for High-Performance Computing National Applied Research Laboratories No. 7 R&D 6th Rd. Hsinchu Science Park Hsinchu30076 Taiwan Department of Civil and Disaster Prevention Engineering National United University No. 2 Lienda Miaoli360001 Taiwan

Coupled 1d-2d hydrodynamic models are widely utilized in flood hazard mapping. researchers have explored several uncertainties in flood hazard mapping, but have not addressed the uncertainty of drainage density. drainage density is equal to total length of the drainage divided by the catchment area. The model sets denser the tributary drainages for higher drainage density values. This study uses a designed case and a real case, Yanshuixi drainage in Tainan, Taiwan, to assess the uncertainty of drainage density in flood hazard mapping. Analytical results indicate that under the same return period rainfall, reduction in tributary drainages in a model (indicating a lower drainage density) results in an underestimate of the flooded area in tributary drainages. This underestimate causes higher peak discharges and total volume of discharges in the drainages, leading to flooding in certain downstream reaches, thereby overestimating the flooded area. The uncertainty of drainage density decreases with increased rainfall. We suggest that modeling flood hazard mapping with low return period rainfalls requires tributary drainages. For extreme rainfall events, a lower drainage density could be selected, but the drainage density of local key areas should be raised. © 2021, CC BY.

关键词： rain

Few-nucleon and many-nucleon systems with semilocal coordinate-space regularized chiral nucleon-nucleon forces

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Physical review C 2018年第1期98卷 014002-014002页

作者： S. Binder A. Calci E. Epelbaum r. J. Furnstahl J. Golak K. Hebeler T. Hüther H. Kamada H. Krebs P. Maris Ulf-G. Meißner A. Nogga r. roth r. Skibiński K. Topolnicki J. P. Vary K. Vobig H. Witała Department of Physics and Astronomy University of Tennessee Knoxville Tennessee 37996 USA Physics Division Oak Ridge National Laboratory Oak Ridge Tennessee 37831 USA TRIUMF 4004 Wesbrook Mall Vancouver British Columbia V6T 2A3 Canada Institut für Theoretische Physik II Ruhr-Universität Bochum D-44780 Bochum Germany Department of Physics The Ohio State University Columbus Ohio 43210 USA M. Smoluchowski Institute of Physics Jagiellonian University PL-30348 Kraków Poland Institut für Kernphysik Technische Universität Darmstadt 64289 Darmstadt Germany Department of Physics Faculty of Engineering Kyushu Institute of Technology Kitakyushu 804-8550 Japan Department of Physics and Astronomy Iowa State University Ames Iowa 50011 USA Helmholtz-Institut für Strahlen- und Kernphysik and Bethe Center for Theoretical Physics Universität Bonn D-53115 Bonn Germany Institut für Kernphysik Institute for Advanced Simulation and Jülich Center for Hadron Physics Forschungszentrum Jülich D-52425 Jülich Germany JARA-High Performance Computing Forschungszentrum Jülich D-52425 Jülich Germany

We employ a variety of ab initio methods, including Faddeev-Yakubovsky equations, no-core configuration interaction approach, coupled-cluster theory, and in-medium similarity renormalization group, to perform a comprehensive analysis of the nucleon-deuteron elastic and breakup reactions and selected properties of light and medium-mass nuclei up to Ca48 using the recently constructed semilocal coordinate-space regularized chiral nucleon-nucleon potentials. We compare the results with those based on selected phenomenological and chiral EFT two-nucleon potentials, discuss the convergence pattern of the chiral expansion, and estimate the achievable theoretical accuracy at various chiral orders using an approach to quantify truncation errors of the chiral expansion without relying on cutoff variation. We also address the robustness of this method and explore alternative ways to estimate the theoretical uncertainty from the truncation of the chiral expansion.

关键词： Few-body systems Nuclear forces

Modeling Interfacial delamination and Critical dimension in Patterned Silicon Thin Film Electrodes for Improved Cycling Stability

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ECS Meeting Abstracts 2011年第10期MA2011-01卷

作者： Hamed Haftbaradaran Xingcheng Xiao Sumit K. Soni Audry Chng Mark Verbrugge William Curtin Brian Sheldon Kyung-Suk Kim Huajian Gao Brown University 182 Hope Street Providence RI 02901 General Motors Global R&D Center School of Engineering Brown University 182 Hope St. PROVIDENCE RI 02906 Institute of High Performance Computing General Motors R&D Center Brown University School of Engineering Brown University Brown University Providence Rhode Island 02912

Abstract not Available.

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Simulating the LOcal Web (SLOW) II. Properties of local galaxy clusters

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arXiv 2024年

作者： Hernández-Martínez, Elena dolag, Klaus Seidel, Benjamin Sorce, Jenny G. Aghanim, Nabila Pilipenko, Sergey Gottlöber, Stefan Lebeau, Théo Valentini, Milena Universitäts-Sternwarte Fakultät für Physik Ludwig-Maximilians-Universität München Scheinerstr.1 München81679 Germany Max Planck Institute for Astrophysics Karl-Schwarzschild-Str. 1 GarchingD-85741 Germany Univ. Lille CNRS Centrale Lille UMR 9189 CRIStAL LilleF-59000 France Université Paris-Saclay CNRS Institut d’Astrophysique Spatiale Orsay91405 France An der Sternwarte 16 PotsdamD-14482 Germany Astronomy Unit Department of Physics University of Trieste Via Tiepolo 11 TriesteI-34131 Italy ICSC - Italian Research Center on High Performance Computing Big Data and Quantum Computing Italy INAF Osservatorio Astronomico di Trieste Via Tiepolo 11 TriesteI-34131 Italy P.N. Lebedev Physical Institute The Russian Academy of Sciences Profsojuznaja 84/32 Moscow117997 Russia

Context. This is the second paper in a series presenting the results from a 500 ℎ−1Mpc large constrained simulation of the local Universe (SLOW). The initial conditions for this cosmological hydro-dynamical simulation are based on peculiar velocities derived from the CosmicFlows-2 catalog. The simulation follows cooling, star formation, and the evolution of super-massive black holes. This allows one to directly predict observable properties of the intracluster medium (ICM) within galaxy clusters, including X-ray luminosity, temperatures, and the Compton-y signal. Aims. Comparing the properties of observed galaxy clusters within the local Universe with the properties of their simulated counterparts enables us to assess the effectiveness of the initial condition constraints in accurately replicating the mildly nonlinear properties of the largest, collapsed objects within the simulation. Methods. Based on the combination of several, publicly available surveys we compiled a sample of galaxy clusters within the local Universe, of which we were able to cross-identify 46 of them with an associated counterpart within the SLOW simulation. We then derived the probability of the cross identification based on mass, X-ray luminosity, temperature, and Compton-y by comparing it to a random selection. results. Our set of 46 cross-identified local Universe clusters contains the 13 most massive clusters from the Planck SZ catalog as well as 70% of clusters with M500 larger than 2 × 1014 M☉. Compared to previous constrained simulations of the local volume, we found in SLOW a much larger amount of replicated galaxy clusters, where their simulation-based mass prediction falls within the uncertainties of the observational mass estimates. Comparing the median observed and simulated masses of our cross-identified sample allows us to independently deduce a hydrostatic mass bias of (1 − b) ≈ 0.87. Conclusions. The SLOW constrained simulation of the local Universe faithfully reproduces numero

关键词： Cosmology

Turbulent pressure support in galaxy clusters Impact of the hydrodynamical solver

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arXiv 2024年

作者： Groth, Frederick Valentini, Milena Steinwandel, Ulrich P. Vallés-Pérez, david dolag, Klaus Universitäts-Sternwarte Fakultät für Physik Ludwig-Maximilians-Universität München Scheinerstr. 1 München81679 Germany Astronomy Unit Department of Physics University of Trieste via Tiepolo 11 TriesteI-34131 Italy INAF - Osservatorio Astronomico di Trieste via Tiepolo 11 TriesteI-34131 Italy ICSC - Italian Research Center on High Performance Computing Big Data and Quantum Computing via Magnanelli 2 Casalecchio di Reno40033 Italy Center for Computational Astrophysics Flatiron Institute 162 Fifth Avenue New YorkNY10010 United States Departament d’Astronomia i Astrofísica Universitat de València C/Doctor Moliner 50 Burjassot ValènciaE-46100 Spain Max-Planck-Institut für Astrophysik Karl-Schwarzschild-Straße 1 Garching85741 Germany

Context. The amount of turbulent pressure in galaxy clusters is still debated, especially as for the impact of the dynamical state and the hydro-method used for simulations. Aims. We study the turbulent pressure fraction in the intra cluster medium of massive galaxy clusters. We aim to understand the impact of the hydrodynamical scheme, analysis method, and dynamical state on the final properties of galaxy clusters from cosmological simulations. Methods. We perform non-radiative simulations of a set of zoom-in regions of seven galaxy clusters with Meshless Finite Mass (MFM) and Smoothed Particle Hydrodynamics (SPH). We use three different analysis methods based on: (i) the deviation from hydrostatic equilibrium, (ii) the solenoidal velocity component obtained by a Helmholtz-Hodge decomposition, and (iii) the small-scale velocity obtained through a multi-scale filtering approach. We split the sample of simulated clusters into active and relaxed clusters. results. Our simulations predict an increased turbulent pressure fraction for active compared to relaxed clusters. This is especially visible for the velocity-based methods. For these, we also find increased turbulence for the MFM simulations compared to SPH, consistent with findings from more idealized simulations. The predicted non-thermal pressure fraction varies between a few percent for relaxed clusters and ≈ 13% for active ones within the cluster center and increases towards the outskirts. No clear trend with redshift is visible. Conclusions. Our analysis quantitatively assesses the importance played by the hydrodynamical scheme and the analysis method to determine the non-thermal/turbulent pressure fraction. While our setup is relatively simple (non-radiative runs), our simulations show agreement with previous, more idealized simulations, and make a step further toward the understanding of turbulence. Copyright © 2024, The Authors. All rights reserved.

关键词： Cosmology

Pion transition form factor from twisted-mass lattice QCd and the hadronic light-by-light π0-pole contribution to the muon g−2

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Physical review d 2023年第9期108卷 094514-094514页

作者： C. Alexandrou S. Bacchio G. Bergner S. Burri J. Finkenrath A. Gasbarro K. Hadjiyiannakou K. Jansen G. Kanwar B. Kostrzewa G. Koutsou K. Ottnad M. Petschlies F. Pittler F. Steffens C. Urbach U. Wenger Department of Physics University of Cyprus 20537 Nicosia Cyprus Computation-based Science and Technology Research Center The Cyprus Institute 20 Konstantinou Kavafi Street 2121 Nicosia Cyprus University of Jena Institute for Theoretical Physics Max-Wien-Platz 1 D-07743 Jena Germany Albert Einstein Center for Fundamental Physics Institute for Theoretical Physics University of Bern Sidlerstrasse 5 CH–3012 Bern Switzerland Bergische Universität Wuppertal Gaußstraße 20 42119 Wuppertal Germany Deutsches Elektronen-Synchrotron DESY Platanenallee 6 15738 Zeuthen Germany High Performance Computing and Analytics Lab Rheinische Friedrich-Wilhelms-Universität Bonn Friedrich-Hirzebruch-Allee 8 D-53115 Bonn Germany PRISMA+ Cluster of Excellence and Institut für Kernphysik Johannes Gutenberg-Universität Mainz Johann-Joachim-Becher-Weg 45 D-55128 Mainz Germany HISKP (Theory) Rheinische Friedrich-Wilhelms-Universität Bonn Nussallee 14-16 D-53115 Bonn Germany Bethe Center for Theoretical Physics Rheinische Friedrich-Wilhelms-Universität Bonn Wegelerstraße 10 D-53115 Bonn Germany

The neutral pion generates the leading pole contribution to the hadronic light-by-light tensor, which is given in terms of the nonperturbative transition form factor Fπ0γγ(q12,q22). Here we present an ab-initio lattice calculation of this quantity in the continuum and at the physical point using twisted-mass lattice QCd. We report our results for the transition form factor parametrized using a model-independent conformal expansion valid for arbitrary spacelike kinematics and compare it with experimental measurements of the single-virtual form factor, the two-photon decay width, and the slope parameter. We then use the transition form factors to compute the pion-pole contribution to the hadronic light-by-light scattering in the muon g−2, finding aμπ0−pole=56.7(3.2)×10−11.

关键词： Lattice field theory Magnetic moment Pions Form factors Ab initio calculations Lattice QCd Path-integral Monte Carlo

Pseudoscalar-pole contributions to the muon g-2 at the physical point

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arXiv 2022年

作者： Burri, S. Kanwar, G. Alexandrou, C. Bacchio, S. Bergner, G. Finkenrath, J. Gasbarro, A. Hadjiyiannakou, K. Jansen, K. Kostrzewa, B. Koutsou, G. Ottnad, K. Petschlies, M. Pittler, F. Steffens, F. Urbach, C. Wenger, U. Albert Einstein Center for Fundamental Physics Institute for Theoretical Physics University of Bern Sidlerstrasse 5 BernCH–3012 Switzerland Department of Physics University of Cyprus Nicosia20537 Cyprus Computation-based Science and Technology Research Center The Cyprus Institute 20 Konstantinou Kavafi Street Nicosia2121 Cyprus University of Jena Institute for Theoretical Physics Max-Wien-Platz 1 JenaD-07743 Germany Deutsches Elektronen-Synchrotron DESY Platanenallee 6 Zeuthen15738 Germany High Performance Computing and Analytics Lab Rheinische Friedrich-Wilhelms-Universität Bonn Friedrich-Hirzebruch-Allee 8 BonnD-53115 Germany PRISMA+ Cluster of Excellence Institut für Kernphysik Johannes Gutenberg-Universität Mainz Johann-Joachim-Becher-Weg 45 MainzD-55128 Germany Rheinische Friedrich-Wilhelms-Universität Bonn Nussallee 14-16 BonnD-53115 Germany Bethe Center for Theoretical Physics Rheinische Friedrich-Wilhelms-Universität Bonn Wegelerstraße 10 BonnD-53115 Germany

Pseudoscalar-pole diagrams are an important component of estimates of the hadronic light-by-light (HLbL) contribution to the muon g − 2. We report on our computation of the transition form factors Fp→γ∗γ∗ for the neutral pseudoscalar mesons P = π0 and η. The calculation is performed using twisted-mass lattice QCd with physical quark masses. On the lattice, we have access to a broad range of (space-like) photon four-momenta and therefore produce form factor data complementary to the experimentally accessible single-virtual direction, which directly leads to an estimate of the pion- and η-pole components of the muon g − 2. For the pion, our result for the g − 2 contribution in the continuum is comparable with previous lattice and data-driven determinations, with combined relative uncertainties below 10%. For the η meson, we report on a preliminary determination from a single lattice spacing. Copyright © 2022, The Authors. All rights reserved.

关键词： Poles