Nuclear Theory·nucl-th
9 papers—4 primary·5 cross-listed
A. Dainese🇮🇹 · M. Diehl🇩🇪 · P. Di Nezza🇮🇹 · J. Friedrich🇩🇪 · M. Gaździcki🇩🇪 · G. Graziani🇮🇹 · C. Hadjidakis🇫🇷 · J. Jäckel🇩🇪 · J. P. Lansberg🇫🇷 · A. Magnon🇨🇭 · G. Mallot🇨🇭 · F. Martinez Vidal🇪🇸 and 11 other authors
This report summarises the main findings of the QCD Working Group in the CERN Physics Beyond Colliders Study.
Eva Lope Oter🇪🇸 · Andreas Windisch🇺🇸 · Felipe J. Llanes-Estrada🇪🇸 · Mark Alford🇺🇸
We contribute a publicly available set of tables and code to provide Equations of State (EoS) for matter at neutron star densities. Our EoSes are constrained only by input from hadron physics and fundamental principles, without feedback from neutron star observations, and so without relying on General Relativity. They can therefore be used to test General Relativity itself, as well as modified gravity theories, with neutron star observables, without logical circularity. We have adapted state of the art results from NN chiral potentials for the low--density limit, pQCD results for the asymptotically high-density EoS, and use monotonicity and causality as the only restrictions for intermediate densities, for the EoS sets to remain as model-independent as is feasible today.
We discuss solutions of an algebraic model of the hexagonal lattice vibrations, which point out interesting localization properties of the eigenstates at van Hove singularities (vHs), whose energies correspond to Excited-State Quantum Phase Transitions (ESQPT). We show that these states form stripes oriented parallel to the zig-zag direction of the lattice, similar to the well-known edge states found at the Dirac point, however the vHs-stripes appear in the bulk. We interpret the states as lines of cell-tilting vibrations, and inspect their stability in the large lattice-size limit. The model can be experimentally realized by superconducting 2D microwave resonators containing triangular lattices of metallic cylinders, which simulate finite-sized graphene flakes. Thus we can assume that the effects discussed here could be experimentally observed.
In this paper the nuclear configurational entropy of the energy--energy correlation function is scrutinized, in collisions to hadrons in the back-to-back region, within the QCD perturbative theory. The critical points of the nuclear configurational entropy concept, in the hot nuclear system, is shown to correspond to the critical angle between the two scattered hadrons, corroborating with phenomenological data with great accuracy. The main tools employ the main coefficients of the soft-gluon resummation formula, taking into account logarithmically enhanced contributions up to next-to-next-to-leading logarithmic accuracy.
Joseph Karpie🇺🇸 · Kostas Orginos🇺🇸 · Alexander Rothkopf · Savvas Zafeiropoulos🇩🇪
The computation of the parton distribution functions (PDF) or distribution amplitudes (DA) of hadrons from first principles lattice QCD constitutes a central open problem. In this study, we present and evaluate the efficiency of a selection of methods for inverse problems to reconstruct the full -dependence of PDFs. Our starting point are the so called Ioffe time PDFs, which are accessible from Euclidean time calculations in conjunction with a matching procedure. Using realistic mock data tests, we find that the ill-posed incomplete Fourier transform underlying the reconstruction requires careful regularization, for which both the Bayesian approach as well as neural networks are efficient and flexible choices.
first authorsco-authorsvia INSPIRE