0000000000398814

AUTHOR

S. Di Ruzza

showing 3 related works from this author

On the propagation of a perturbation in an anharmonic system

2007

We give a not trivial upper bound on the velocity of disturbances in an infinitely extended anharmonic system at thermal equilibrium. The proof is achieved by combining a control on the non equilibrium dynamics with an explicit use of the state invariance with respect to the time evolution.

Thermal equilibriumPhysicsAnharmonicityTime evolutionAnharmonic crystals; Propagation velocity; Statistical and Nonlinear Physics; Mathematical PhysicsPerturbation (astronomy)FOS: Physical sciencesStatistical and Nonlinear Physicsanharmonic crystals; propagation velocityMathematical Physics (math-ph)Upper and lower bounds82C05 82D20Classical mechanicsPropagation velocityAnharmonic crystalsSettore MAT/07 - Fisica MatematicaMathematical Physics
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Nearly-integrable dissipative systems and celestial mechanics

2010

The influence of dissipative effects on classical dynamical models of Celestial Mechanics is of basic importance. We introduce the reader to the subject, giving classical examples found in the literature, like the standard map, the Hénon map, the logistic mapping. In the framework of the dissipative standard map, we investigate the existence of periodic orbits as a function of the parameters. We also provide some techniques to compute the breakdown threshold of quasi-periodic attractors. Next, we review a simple model of Celestial Mechanics, known as the spin-orbit problem which is closely linked to the dissipative standard map. In this context we present the conservative and dissipative KA…

PhysicsDynamical systems theoryKolmogorov–Arnold–Moser theoremGeneral Physics and AstronomyStandard mapInvariant (physics)Three-body problemCelestial mechanicsPhysics and Astronomy (all)Classical mechanicsAttractorIntegrable systemsDissipative systemGeneral Materials ScienceMaterials Science (all)Physical and Theoretical ChemistryMaterials Science (all); Physics and Astronomy (all); Physical and Theoretical ChemistrySettore MAT/07 - Fisica MatematicaThe European Physical Journal Special Topics
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The BepiColombo MORE gravimetry and rotation experiments with the ORBIT14 software

2016

The BepiColombo mission to Mercury is an ESA/JAXA cornerstone mission, consisting of two spacecraft in orbit around Mercury addressing several scientific issues. One spacecraft is the Mercury Planetary Orbiter, with full instrumentation to perform radio science experiments. Very precise radio tracking from Earth, on-board accelerometer and optical measurements will provide large data sets. From these it will be possible to study the global gravity field of Mercury and its tidal variations, its rotation state and the orbit of its centre of mass. With the gravity field and rotation state, it is possible to constrain the internal structure of the planet. With the orbit of Mercury, it is possib…

010504 meteorology & atmospheric sciencesAccelerometer01 natural scienceslaw.inventionmethods: numericalGravitationOrbiterMethods: numerical; Planets and satellites: individual: Mercury; Space vehicles: instruments; Astronomy and Astrophysics; Space and Planetary ScienceGravitational fieldmethods: numerical – space vehicles: instruments – planets and satellites: individual: Mercurylaw0103 physical sciencesGravimetryAerospace engineeringspace vehicles: instrumentsSettore MAT/07 - Fisica Matematica010303 astronomy & astrophysics0105 earth and related environmental sciencesRemote sensingRadio SciencePhysicsSpacecraftbusiness.industryAstronomy and AstrophysicsSpace and Planetary SciencePhysics::Space PhysicsLove numberAstrophysics::Earth and Planetary Astrophysicsbusinessplanets and satellites: individual: Mercury
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