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Concept

Mouvement coorbital

Publications associées (24)

Gaia Focused Product Release: Asteroid orbital solution: Properties and assessment

Stephan Morgenthaler, Shuangqing Liao

Context. We report the exploitation of a sample of Solar System observations based on data from the third Gaia Data Release (Gaia DR3) of nearly 157 000 asteroids. It extends the epoch astrometric solution over the time coverage planned for the Gaia DR4, w ...

Edp Sciences S A2023

The eta Aquilae System: Radial Velocities and Astrometry in Search of eta Aql B

Richard Irving Anderson

The classical Cepheid eta Aql was not included in past Leavitt Law work because of a presumed complicating orbit due to a known B9.8V companion. To determine the orbit of eta Aql B, we analyze a significant number of radial velocity (RV) measurements from ...

2022

Discovery of a Binary-origin Classical Cepheid in a Binary System with a 59 day Orbital Period

Richard Irving Anderson

We report the discovery of a surprising binary configuration of the double-mode Cepheid OGLE-LMC-CEP-1347 pulsating in the first (P-1= 0.690 days) and second-overtone (P-2= 0.556 days) modes. The orbital period (P-orb= 59 days) of the system is five times ...

Iop Publishing Ltd2022

Secular effects of ultralight dark matter on binary pulsars

Sergey Sibiryakov, Diego Blas Temino

Dark matter (DM) can consist of very light bosons behaving as a classical scalar field that experiences coherent oscillations. The presence of this DM field would perturb the dynamics of celestial bodies, either because the (oscillating) DM stress tensor m ...

American Physical Society2020

Analysis of Spiral-Grooved Gas Journal Bearings by the Narrow-Groove Theory and the Finite Element Method At Large Eccentricities

Jürg Alexander Schiffmann, Eliott Philippe Guenat, Elia Iseli

A finite groove approach (FGA), based on the finite element method (FEM), is used for analyzing the static and dynamic behavior of spiral-grooved aerodynamic journal bearings at different eccentricities, number of grooves, and compressibility numbers. The ...

2020

Structural Properties Of Dendrite Groups

Nicolas Monod

Let G be the homeomorphism group of a dendrite. We study the normal subgroups of G. For instance, there are uncountably many nonisomorphic such groups G that are simple groups. Moreover, these groups can be chosen so that any isometric G-action on any metr ...

AMER MATHEMATICAL SOC2019

Hypervelocity impact testing on stochastic and structured open porosity cast Al-Si cellular structures for space applications

Andreas Mortensen

A hypervelocity (6.7–7.0 km/s) impact testing campaign was conducted using Ø 2 mm, 95% Al projectiles onto A357 aluminium alloy stochastic foams with 4–5 mm typical pore dimensions, or alternatively diamond cubic periodic structures of cast AlSi12 with a 6 ...

2018

Periodic cellular aluminum structures for space applications : from casting to additive manufacturing

Florian Thibaut Gallien

Mass is one of the crucial parameters for hardware that has to be placed in Earth orbit. Due to its harsh environment, a material with highest specific properties is desired to achieve space missions. The rise and development of new technologies, such as a ...

EPFL2018

A large planetary body inferred from diamond inclusions in a ureilite meteorite

Cécile Hébert, Emad Oveisi, Marco Cantoni, Philippe Gillet, James Badro, Farhang Nabiei, Teresa Katharina Dennenwaldt

Planetary formation models show that terrestrial planets are formed by the accretion of tens of Moon-to Mars-sized planetary embryos through energetic giant impacts. However, relics of these large proto-planets are yet to be found. Ureilites are one of the ...

Nature Research2018

Fixed Points For Bounded Orbits In Hilbert Spaces

Nicolas Monod, Maxime Gheysens

Consider the following property of a topological group G: every continuous affine G-action on a Hilbert space with a bounded orbit has a fixed point. We prove that this property characterizes amenability for locally compact a-compact groups (e.g., countabl ...

2017

Ultralight Dark Matter Resonates with Binary Pulsars

Sergey Sibiryakov, Diego Blas Temino

We consider the scenario where dark matter (DM) is represented by an ultralight classical scalar field performing coherent periodic oscillations. We point out that such DM perturbs the dynamics of binary systems either through its gravitational field or vi ...

American Physical Society2017

Testing Lorentz invariance of dark matter with satellite galaxies

Sergey Sibiryakov, Diego Blas Temino

We develop the framework for testing Lorentz invariance in the dark matter sector using galactic dynamics. We consider a Lorentz violating (LV) vector field acting on the dark matter component of a satellite galaxy orbiting in a host halo. We introduce a n ...

Iop Publishing Ltd2017

SATELLITE CONSTELLATION DESIGN FOR THE SOLVE MISSION INVESTIGATING DIURNAL CYCLES OF VEGETATION PHENOMENA

Anton Ivanov, Luzius Gregor Kronig, Olivier Ladislas Alain de Weck

This paper discusses the problem of finding an optimal satellite constellation for the SOLVE (Satellites Observing Lakes and Vegetation Environments) Mission. A key requirement of this mission is a temporal resolution of several observations per day. A sem ...

2016

Diamond optomechanical crystals in the resolved-sideband regime

We demonstrate diamond optomechanical crystals (OMCs), which support a similar to 6 GHz mechanical cavity coupled to a co-resonant similar to 200 THz photon field. Diamond OMCs are optically driven to a cooperativity >1, highlighted by observed 'phonon las ...

Ieee2016

Photophysical and Computational Analysis of a Symmetrical Fluorene-Based Janus Dione Derivative

Alma Rosa Morales Morales

Molecular symmetry plays an important role in the physical characteristics and spectra of a molecule. However, experimental results can sometimes be counterintuitive due to unpredictable properties of a molecule. Photophysical characterization of a centros ...

American Chemical Society2015

Coherent creation and destruction of orbital wavepackets in Si:P with electrical and optical read-out

The ability to control dynamics of quantum states by optical interference, and subsequent electrical read-out, is crucial for solid state quantum technologies. Ramsey interference has been successfully observed for spins in silicon and nitrogen vacancy cen ...

Nature Publishing Group2015

Collisionless microtearing modes in hot tokamaks: Effect of trapped electrons

Laurent Villard, Stephan Brunner

Collisionless microtearing modes have recently been found linearly unstable in sharp temperature gradient regions of large aspect ratio tokamaks. The magnetic drift resonance of passing electrons has been found to be sufficient to destabilise these modes a ...

Amer Inst Physics2015

Hybrid guiding-centre/full-orbit simulations in non-axisymmetric magnetic geometry exploiting general criterion for guiding-centre accuracy

Jonathan Graves, Wilfred Anthony Cooper, David Pfefferlé

To identify under what conditions guiding-centre or full-orbit tracing should be used, an estimation of the spatial variation of the magnetic field is proposed, not only taking into account gradient and curvature terms but also parallel currents and the lo ...

Iop Publishing Ltd2015

Planck 2013 results. VIII. HFI photometric calibration and mapmaking

Xin Chen, Julien Lesgourgues

This paper describes the methods used to produce photometrically calibrated maps from the Planck High Frequency Instrument (HFI) cleaned, time-ordered information. HFI observes the sky over a broad range of frequencies, from 100 to 857 GHz. To obtain the b ...

Edp Sciences S A2014

The ESPRI project: astrometric exoplanet search with PRIMA I. Instrument description and performance of first light observations

Ludger Weber

Context. The ESPRI project relies on the astrometric capabilities offered by the PRIMA facility of the Very Large Telescope Interferometer for discovering and studying planetary systems. Our survey consists of obtaining high-precision astrometry for a larg ...

Edp Sciences S A2013