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Mercury-Arχes: an high-performance n-body code for planet formation simulations
Get PDF<p>Mercury-Arχes is the parallel n-body code of Arχes, the INAF suite of planet formation and astrochemistry codes. Building on the Mercury n-body code, Mercury-Arχes integrates planet formation libraries to track the growth, migration and interactions with the disk gas of planetary bodies.</p>
EuroSIG FRAMEWORK - CONCEPTUAL DESIGN REPORT OF THE SUPERCONDUCTING ION GANTRY (SIG) DIPOLE DEMONSTRATOR MAGNET
No full text<p>This Conceptual Design Report (CDR) concerns the demonstrator of a curved dipole demonstrator magnet for an innovative superconducting gantry for ion therapy. The demonstrator will be realized in the framework of both the INFN (the Italian National Institute for Nuclear Physics) grant SIG (Superconducting Ion Gantry) and of the international collaboration EuroSIG among INFN, CNAO, CERN, and MedAustron. SIG and EuroSIG aim to demonstrate enabling technologies for nextgeneration ion gantries and they overlap in several developments while at the same time pursuing some solutions independently. After a brief overview of the gantry optical layout and requirements, the report illustrates the adopted conductor, the electromagnetic design of the demonstrator with the relative guiding principles, its thermal design and quench behavior and its structural design. For the structural design, a sensitivity analysis is conducted taking into account the possible tolerances, uncertainties in the material properties, and also and different materials. An alternative winding technique is developed as a backup solution and it applies to a coil block magnet design.</p>
A general learning scheme for classical and quantum Ising machines
No full textAn Ising machine is any hardware specifically designed for finding the ground state of the Ising model. Relevant examples are coherent Ising machines and quantum annealers. In this paper, we propose a new machine learning model that is based on the Ising structure and can be efficiently trained using gradient descent. We provide a mathematical characterization of the training process, which is based upon optimizing a loss function whose partial derivatives are not explicitly calculated but estimated by the Ising machine itself. Moreover, we present some experimental results on the training and execution of the proposed learning model. These results point out new possibilities offered by Ising machines for different learning tasks. In particular, in the quantum realm, the quantum resources are used for both the execution and the training of the model, providing a promising perspective in quantum machine learning
On the Stochastic Sine-Gordon Model: An Interacting Field Theory Approach
No full textWe investigate the massive sine-Gordon model in the finite ultraviolet regime on the two-dimensional Minkowski spacetime with an additive Gaussian white noise. In particular we construct the expectation value and the correlation functions of a solution of the underlying stochastic partial differential equation (SPDE) as a power series in the coupling constant, proving ultimately uniform convergence. This result is obtained combining an approach first devised in Dappiaggi et al. (Commun Contemp Math 24(07):2150075, 2022. arXiv:2009.07640 [math-ph]) to study SPDEs at a perturbative level with the one discussed in Bahns and Rejzner (Commun Math Phys 357(1):421, 2018. arXiv:1609.08530 [math-ph]) to construct the quantum sine-Gordon model using techniques proper of the perturbative, algebraic approach to quantum field theory (pAQFT). At a formal level the relevant expectation values are realized as the evaluation of suitably constructed functionals over . In turn, these are elements of a distinguished algebra whose product is a deformation of the pointwise one, by means of a kernel which is a linear combination of two components. The first encompasses the information of the Feynmann propagator built out of an underlying Hadamard, quantum state, while the second encodes the correlation codified by the Gaussian white noise. In our analysis, first of all we extend the results obtained in Bahns et al. (J Math Anal Appl 526:127249, 2023. arXiv:2103.09328 [math-ph]) and Bahns and Rejzner (Commun Math Phys 357(1):421, 2018. arXiv:1609.08530 [math-ph]) proving the existence of a convergent modified version of the S-matrix and of an interacting field as elements of the underlying algebra of functionals. Subsequently we show that it is possible to remove the contribution due to the Feynmann propagator by taking a suitable -limit, hence obtaining the sought expectation value of the solution and of the correlation functions of the SPDE associated to the stochastic sine-Gordon model
Large N expansion of superconformal index of k = 1 ABJM theory and semiclassical M5 brane partition function
No full textIt was shown in arXiv:2309.10786 that the leading non-perturbative contribution to the large N expansion of the superconformal index of the (2,0) 6d theory (which describes low-energy dynamics of N coincident M5 branes) is reproduced by the semiclassical partition function of quantum M2 brane wrapped on S1×S2 in a twisted version of AdS×7S4 background. Here we demonstrate an analogous relation for the leading non-perturbative contribution to the large N expansion of the superconformal index of the N=8 supersymmetric level-one U(N)×U(N) ABJM theory (which describes low-energy dynamics of N coincident M2 branes). The roles of M2 and M5 branes get effectively interchanged. Namely, the large N correction to the ABJM index is found to be given by the semiclassical partition function of quantum M5 brane wrapped on S1×S5 in a twisted version of AdS×4S7 background. This effectively confirms the suggestion for the "M5 brane index" made in arXiv:2007.05213 on the basis of indirect superconformal algebra considerations
Multi-charmed and singled charmed hadrons from coalescence: yields and ratios in different collision systems at LHC
No full textWe study the production of charmed and multi-charmed hadrons in ultra-relativistic Heavy Ion Collisions coupling the transport approach for charm dynamics in the medium to an hybrid hadronization model of coalescence plus fragmentation. In this paper, we mainly discuss the particle yields for single charmed and multi-charmed baryons focusing mainly on the production of and . We provide first predictions for PbPb collision in centrality class and then we explore the system size dependence through KrKr , to ArAr and OO collisions, planned within the ALICE3 experiment. In these cases, a monotonic behavior for the yields emerges which can be tested in future experimental data. We found about three order of magnitude increase in the production of in PbPb collisions compared with the yield in small collision systems like OO collisions. Furthermore, we investigate the effects on the particle yield and spectra coming from the modification of the charm quark distribution due to the different size of the collision systems also comparing it to the case of thermalized charm distributions. These results suggest that observation on the spectra and their evolution across system size can give novel information about the partial thermalization of the charm quark distribution as well as to its wave function width. Furthermore, we find that the / ratio is an observable more sensitive with respect to / , this ratio is predicted to span over two order of magnitude from large to small systems
Low-energy spectrum of the BULLKID detector array operated on surface
No full textWe present the first continuous operation in a surface lab of BULLKID, a detector for searches of light Dark Matter and precision measurements of the coherent and elastic neutrino-nucleus scattering. The detector consists of an array of 60 cubic silicon particle absorbers of 0.34 g each, sensed by cryogenic kinetic inductance detectors. The data presented focusses on one of the central elements of the array and on its surrounding elements used as veto. The energy spectrum resulting from an exposure of 39 h to ambient backgrounds, obtained without radiation shields, is flat at the level of counts/keV kg days down to the energy threshold of eV. The data analysis demonstrates the unique capability of rejecting backgrounds generated from interactions in other sites of the array, stemming from the segmented and monolithic structure of the detector
Multiparticle states in braided lightlike <math display="inline"><mrow><mi>κ</mi></mrow></math>-Minkowski noncommutative QFT
No full textIn this study, we construct a 1+1-dimensional, relativistic, free, complex scalar quantum field theory on the noncommutative spacetime known as lightlike κ-Minkowski. The associated κ-Poincaré quantum group of isometries is triangular, and its quantum R matrix enables the definition of a braided algebra of N points that retains κ-Poincaré invariance. Leveraging our recent findings, we can now represent the generators of the deformed oscillator algebra as nonlinear redefinitions of undeformed oscillators, which are nonlocal in momentum space. The deformations manifest at the multiparticle level, as the one-particle states are identical to the undeformed ones. We successfully introduce a covariant and involutive deformed flip operator using the R matrix. The corresponding deformed (anti)symmetrization operators are covariant and idempotent, allowing for a well-posed definition of multiparticle states, a result long sought in quantum field theory on κ-Minkowski. We find that P and T are not symmetries of the theory, although PT (and hence CPT) is. We conclude by noticing that identical particles appear distinguishable in the new theory, and discuss the fate of the Pauli exclusion principle in this setting
Equivalence principle violation in nonminimally coupled gravity and constraints from lunar laser ranging
No full textWe analyze the dynamics of the Sun-Earth-Moon system in the context of a particular class of theories of gravity where curvature and matter are nonminimally coupled. These theories can potentially violate the equivalence principle as they give origin to a fifth force and a extra non-Newtonian force that may imply that Earth and Moon fall differently towards the Sun. We show, through a detailed analysis, that consistency with the bound on weak equivalence principle arising from 48 years of lunar laser ranging data, for a range of parameters of the nonminimally coupled gravity theory, can be achieved via the implementation of a suitable screening mechanism
Variational quantum simulation of U(1) lattice gauge theories with qudit systems
No full textLattice gauge theories are fundamental to various fields, including particle physics, condensed matter, and quantum information theory. Recent progress in the control of quantum systems allows for studying Abelian lattice gauge theories in table-top experiments. However, several challenges remain, such as implementing dynamical fermions in higher spatial dimensions and magnetic field terms. Here, we map U(1) Abelian lattice gauge theories in arbitrary spatial dimensions onto qudit systems with local interactions. We propose a variational quantum simulation scheme for the qudit system with a local Hamiltonian, that can be implemented on a universal qudit quantum device as the one developed in [Nat. Phys. 18, 1053 (2022)]. We describe how to implement the variational imaginary-time evolution protocol for ground-state preparation as well as the variational real-time evolution protocol to simulate nonequilibrium physics on universal qudit quantum computers, supplemented with numerical simulations. Our proposal can serve as a way of simulating lattice gauge theories, particularly in higher spatial dimensions, with minimal resources, regarding both system sizes and gate count