Publications associées à Masse de Chandrasekhar

White dwarfs as a probe of exceptionally light QCD axions

We study the effects of exceptionally light QCD axions on the stellar configuration of white dwarfs. At finite baryon density, the nonderivative coupling of the axion to nucleons displaces the axion from its invacuum minimum, which implies a reduction of t ...

American Physical Society2024

Search for Inelastic Dark Matter in Events with Two Displaced Muons and Missing Transverse Momentum in Proton-Proton Collisions at p s=13 TeV

Matthias Finger, Konstantin Androsov, Qian Wang, Jan Steggemann, Anna Mascellani, Yiming Li, Varun Sharma, Xin Chen, Rakesh Chawla, Matteo Galli, Jian Wang, João Miguel das Neves Duarte, Tagir Aushev, Matthias Wolf, Yi Zhang, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Siyuan Wang, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Kun Shi, Abhisek Datta, Federica Legger, Gabriele Grosso, Ji Hyun Kim, Donghyun Kim, Zheng Wang, Sanjeev Kumar, Wei Li, Yong Yang, Ajay Kumar, , , , , , , , , , , , , , , , , , , , ,

Metallicity Distribution Functions of 13 Ultra-faint Dwarf Galaxy Candidates from Hubble Space Telescope Narrowband Imaging

Nicolas Lawrence Etienne Longeard

We present uniformly measured stellar metallicities of 463 stars in 13 Milky Way (MW) ultra-faint dwarf galaxies (UFDs; M-V = -7.1 to -0.8) using narrowband CaHK (F395N) imaging taken with the Hubble Space Telescope. This represents the largest homogeneous ...

Iop Publishing Ltd2023

Feasibility of the EDICAM camera for runaway electron detection in JT-60SA disruptions

The visible camera system EDICAM (Event Detection Intelligent Camera), recently installed on JT-60SA, is simulated to assess whether it can be used for measuring synchrotron radiation from relativistic runaway electrons. In this simulation, the SOFT synthe ...

ELSEVIER SCIENCE SA2023

Runaway dynamics in reactor-scale spherical tokamak disruptions

Understanding generation and mitigation of runaway electrons in disruptions is important for the safe operation of future tokamaks. In this paper we investigate the runaway dynamics in reactor-scale spherical tokamaks, focusing on a compact nominal design ...

Cambridge University Press2022

The Pristine survey - XIV. Chemical analysis of two ultra-metal-poor stars

Pascale Jablonka, Carmela Lardo

Elemental abundances of the most metal-poor stars reflect the conditions in the early Galaxy and the properties of the first stars. We present a spectroscopic follow-up of two ultra-metal-poor stars ([Fe/H] < -4.0) identified by the survey Pristine: Pristi ...

OXFORD UNIV PRESS2021

Cold gas in the cosmic web around galaxy clusters

Damien Louis Alexandre Spérone-Longin

Galaxies live in very different types of environment. Those different environments are relics from the evolution of the Universe since the Big Bang. This network of structures observed via large scale surveys is called Cosmic Web. Within this web, galaxies ...

EPFL2021

Runaway electron modelling in the self-consistent core European Transport Simulator

Joan Decker, Gergely Papp

Relativistic runaway electrons are a major concern in tokamaks. Although significant theoretical development had been undertaken in recent decades, we still lack a self-consistent simulator that could simultaneously capture all aspects of this phenomenon. ...

IOP Publishing Ltd2019

The Gaia-ESO Survey: Galactic evolution of sulphur and zinc

Carmela Lardo

Context. Due to their volatile nature, when sulphur and zinc are observed in external galaxies, their determined abundances represent the gas-phase abundances in the interstellar medium. This implies that they can be used as tracers of the chemical enrichm ...

Edp Sciences S A2017

Stellar-to-halo mass relation of cluster galaxies

Jean-Paul Richard Kneib, Huanyuan Shan

In the formation of galaxy groups and clusters, the dark matter haloes containing satellite galaxies are expected to be tidally stripped in gravitational interactions with the host. We use galaxy-galaxy weak lensing to measure the average mass of dark matt ...

Oxford Univ Press2017

Numerical characterization of bump formation in the runaway electron tail

Joan Decker

Runaway electrons are generated in a magnetized plasma when the parallel electric field exceeds a critical value. For such electrons with energies typically reaching tens of MeV, the Abrahamâ Lorentzâ Dirac (ALD) radiation force, in reaction to the synch ...

Iop Publishing Ltd2016

An advection-diffusion model for cross-field runaway electron transport in perturbed magnetic fields

Joan Decker

Disruption-generated runaway electrons (RE) present an outstanding issue for ITER. The predictive computational studies of RE generation rely on orbit-averaged computations and, as such, they lack the effects from the magnetic field stochasticity. Since st ...

Iop Publishing Ltd2016

Numerical simulation of a collapsing bubble subject to gravity

Mohamed Farhat, Outi Supponen

The present paper focuses on the simulation of the expansion and aspherical collapse of a laser-generated bubble subjected to an acceleration field and comparison of the results with instances from high-speed videos. The interaction of the liquid and gas i ...

Amer Inst Physics2016

Evaluating the effect of stellar multiplicity on the point spread function of space-based weak lensing surveys

Frédéric Courbin, Georges Meylan, Thibault Adrien Kuntzer

The next generation of space-based telescopes used for weak lensing surveys will require exquisite point spread function (PSF) determination. Previously negligible effects may become important in the reconstruction of the PSF, in part because of the improv ...

Edp Sciences S A2016

Increasing the stability of nanofluids with cavitating flows in micro orifices

Yusuf Leblebici, Morteza Ghorbani

One of the most critical challenges for nanofluids in practical applications is related to their stability and reusability since a gradual agglomeration of nanoparticles in nanofluids occurs with time and is accelerated by heating. In this study, we propos ...

Amer Inst Physics2016

Scaling laws for jets of single cavitation bubbles

Mohamed Farhat, Nicolas Dorsaz, Danail Obreschkow, Philipp Kobel, Outi Supponen, Marc Tinguely

Fast liquid jets, called micro-jets, are produced within cavitation bubbles experiencing an aspherical collapse. Here we review micro-jets of different origins, scales and appearances, and propose a unified framework to describe their dynamics by using an ...

Cambridge University Press2016

Kinetic modelling of runaway electron avalanches in tokamak plasmas

Joan Decker

Runaway electrons can be generated in tokamak plasmas if the accelerating force from the toroidal electric field exceeds the collisional drag force owing to Coulomb collisions with the background plasma. In ITER, disruptions are expected to generate runawa ...

Iop Publishing Ltd2015

Evidence for major mergers of galaxies at 2 less than or similar to z < 4 in the VVDS and VUDS surveys

Jean-Paul Richard Kneib

Context. The mass assembly of galaxies can proceed through different physical processes. Here we report on the spectroscopic identification of close physical pairs of galaxies at redshifts 2 less than or similar to z < 4 and discuss the impact of major mer ...

EDP Sciences2014

Hubble Space Telescope Grism Spectroscopy Of Extreme Starbursts Across Cosmic Time: The Role Of Dwarf Galaxies In The Star Formation History Of The Universe

Jean-Paul Richard Kneib, Hakim Atek, Patrick Mccarthy

Near infrared slitless spectroscopy with the Wide Field Camera 3, on board the Hubble Space Telescope, offers a unique opportunity to study low-mass galaxy populations at high redshift (z similar to 1-2). While most high-z surveys are biased toward massive ...

American Astronomical Society2014

Science and technology research and development in support to ITER and the Broader Approach at CEA

Yiming Li, Alexis Berne, Antoine Pierre Emmanuel Alexis Merle, Joan Decker, Yi Zhang, Jonathan Bryan Lister, Javier García Hernández, Daniel Keller, Fang Liu, Vincent Martin, Nicolas Mellet, Jonathan Bastien Cottet, Louis Nicolas, Hui Wang, Xiaoxia Bai

In parallel to the direct contribution to the procurement phase of ITER and Broader Approach, CEA has initiated research & development programmes, accompanied by experiments together with a significant modelling effort, aimed at ensuring robust operation, ...

IOP Publishing Ltd2013