Publications associées à Spirale

On the distribution of the cold neutral medium in galaxy discs

The cold neutral medium (CNM) is an important part of the galactic gas cycle and a precondition for the formation of molecular and star-forming gas, yet its distribution is still not fully understood. In this work, we present extremely high resolution simu ...

OXFORD UNIV PRESS2023

From starburst to quenching: merger-driven evolution of the star formation regimes in a shell galaxy

Jonathan Erik Peter Petersson

Shell galaxies make a class of tidally distorted galaxies, characterized by wide concentric arc(s), extending out to large galactocentric distances with sharp outer edges. Recent observations of young massive star clusters in the prominent outer shell of N ...

OXFORD UNIV PRESS2022

Design of magnetic spirals in layered perovskites: Extending the stability range far beyond room temperature

In insulating materials with ordered magnetic spiral phases, ferroelectricity can emerge owing to the breaking of inversion symmetry. This property is of both fundamental and practical interest, particularly with a view to exploiting it in low-power electr ...

AMER ASSOC ADVANCEMENT SCIENCE2018

Two-phase flow phenomena in hydraulic turbines and pump-turbines operating in synchronous condenser mode

Elena Vagnoni

Hydraulic turbines and pump-turbines are often required to operate in particular conditions at which they consume active power. To keep the power consumption at a minimum, it is necessary to dewater the runner to reduce the mechanical torque. One of these ...

EPFL2018

Spiral spin-liquid and the emergence of a vortex-like state in MnSc2S4

Jonathan White, Gregory Scott Tucker, Romain Sibille, Shang Gao

Spirals and helices are common motifs of long-range order in magnetic solids, and they may also be organized into more complex emergent structures such as magnetic skyrmions and vortices. A new type of spiral state, the spiral spin-liquid, in which spins f ...

Nature Publishing Group2017

Direct observation of anisotropic magnetic field response of the spin helix in FeGe thin films

Henrik Moodysson Rønnow, Jonathan White

We report the observation by small-angle neutron scattering (SANS) of a magnetic helical structure confined in a thin film of the chiral lattice magnet FeGe. Twofold magnetic Bragg spots appearing below the magnetic transition temperature indicate the form ...

Amer Physical Soc2016

ASTErIsM: application of topometric clustering algorithms in automatic galaxy detection and classification

Jean-Paul Richard Kneib, Frédéric Courbin, Danuta Janina Paraficz

We present a study on galaxy detection and shape classification using topometric clustering algorithms. We first use the DBSCAN algorithm to extract, from CCD frames, groups of adjacent pixels with significant fluxes and we then apply the DENCLUE algorithm ...

Oxford Univ Press2016

Animation-Based Service Specification, Verification and Validation

Biljana Bajic-Bizumic

[Context] With the expansion of services and service science, service systems have become an important abstraction for the service revolution. Service is defined as the application of resources (including competences, skills, and knowledge) to make changes ...

EPFL2015

Hydroacoustic Simulation of Rotor-Stator Interaction in Resonance Conditions in Francis Pump-Turbine

François Avellan, Christophe Nicolet, Sébastien Alligné, Nicolas Ruchonnet

Combined effect of rotating pressure field related to runner blade and wakes of wicket gates leads to rotor stator interactions, RSI, in Francis pump-turbines. These interactions induce pressures waves propagating in the entire hydraulic machine. Superposi ...

International Association For Hydraulic Research2010

Hydroacoustic modelling and numerical simulation of unsteady operation of hydroelectric systems

Christophe Nicolet

Hydropower represented in 1999 19% of the world electricity production and the absolute production is expected to grow considerably during the next 30 years. Francis turbines play a major role in the hydroelectric production due to their extended range of ...

EPFL2007