Publications associées à Sous-naine brune

Tracing the rise of supermassive black holes A panchromatic search for faint, unobscured quasars at z ≥ 6 with COSMOS-Web and other surveys

We report the identification of 64 new candidates of compact galaxies, potentially hosting faint quasars with bolometric luminosities of L-bol = 10(43)-10(46) erg s(-1), residing in the reionization epoch within the redshift range of 6 less than or similar ...

Edp Sciences S A2024

HD 213258: A new rapidly oscillating, super slowly rotating, strongly magnetic Ap star in a spectroscopic binary

Pierre North

We report on HD 213258, an Ap star that we recently identified as presenting a unique combination of rare, remarkable properties. Our study of this star is based on ESPaDOnS Stokes I and V data obtained at seven epochs spanning a time interval slightly sho ...

EDP SCIENCES S A2023

The formation of the faintest galaxies in cosmological simulations: from the impact of primordial magnetic fields to the metal enrichment of present day dwarfs by first stars

Mahsa Sanati

In the theory of the bottom-up assembly of cosmic structures, one of the main challenges is to connect the smallest, most inconspicuous galaxies we observe today to the building blocks of more massive galaxies such as our own, the Milky Way. Do these so-ca ...

EPFL2023

Predicting hot-electron free energies from ground-state data

Michele Ceriotti, Federico Grasselli, Chiheb Ben Mahmoud

Machine-learning potentials are usually trained on the ground-state, Born-Oppenheimer energy surface, which depends exclusively on the atomic positions and not on the simulation temperature. This disregards the effect of thermally excited electrons, that i ...

AMER PHYSICAL SOC2022

Constraining the primordial magnetic field with dwarf galaxy simulations

Pascale Jablonka, Yves Revaz, Jennifer Waltraud Schober, Mahsa Sanati

Using a set of cosmological hydro-dynamical simulations, we constrained the properties of primordial magnetic fields by studying their impact on the formation and evolution of dwarf galaxies. We performed a large set of simulations (8 dark matter only and ...

EDP SCIENCES S A2020

Tracing the formation of the Milky Way through ultra metal-poor stars

Pascale Jablonka, Nicolas Lawrence Etienne Longeard

We use Gaia DR2 astrometric and photometric data, published radial velocities and MESA models to infer distances, orbits, surface gravities, and effective temperatures for all ultra metal-poor stars ([Fe/H] < -4.0 dex) available in the literature. Assuming ...

OXFORD UNIV PRESS2019

Catalogues of radial and rotational velocities of 1253 F-K dwarfs in 13 nearby open clusters

Jean-Claude Mermilliod

Context. We conducted a long-term monitoring of solar-type dwarfs in 13 nearby open clusters, d < 500 pc, over 19 years, but most individual radial velocities were never published, apart from a small number of spectroscopic binaries. Aims. Our program was ...

2009

An exploratory search for z greater than or similar to 6 quasars in the ukidss early data release

Frédéric Courbin, Georges Meylan, Alexander Patrick Eigenbrod

We conducted an exploratory search for quasars at z similar to 6-8, using the Early Data Release (EDR) from the United Kingdom Infrared Deep Sky Survey (UKIDSS) cross-matched to panoramic optical imagery. High-redshift quasar candidates are chosen using mu ...

2008