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Concept

Classification de Vaucouleurs

Publications associées (31)

Searching for Strong Gravitational Lenses

Frédéric Courbin, Cameron Alexander Campbell Lemon

Strong gravitational lenses provide unique laboratories for cosmological and astrophysical investigations, but they must first be discovered - a task that can be met with significant contamination by other astrophysical objects and asterisms. Here we revie ...

Springer2024

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

Michaela Hirschmann

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

The phase-space distribution of the M 81 satellite system

Oliver Müller, Nick Heesters

The spatial distribution of dwarf galaxies around their host galaxies is a critical test for the standard model of cosmology because it probes the dynamics of dark matter halos and is independent of the internal baryonic processes of galaxies. Comoving pla ...

Edp Sciences S A2024

Examining the relationship between the bulge-to-total stellar mass ratio and dwarf galaxy count in the context of ΛCDM

Oliver Müller

Previous results suggest that there is a correlation between the size of the bulge of a galaxy and the number of its dwarf galaxy satellites. This was found to be inconsistent with the standard model of cosmology based on comparisons to semi-analytical dar ...

Edp Sciences S A2023

Molecular and ionized gas in tidal dwarf galaxies: the spatially resolved star formation relation

Yves Revaz

Tidal dwarf galaxies (TDGs) are low-mass objects that form within tidal and/or collisional debris ejected from more massive interacting galaxies. We use CO(1-0) observations from Atacama Large Millimeter/submillimeter Array and integral-field spectroscopy ...

Oxford Univ Press2023

Euclid preparation XXX. Performance assessment of the NISP red grism through spectroscopic simulations for the wide and deep surveys

Maurizio Martinelli, Frédéric Courbin, Georges Meylan, Michaela Hirschmann, Gianluca Castignani

This work focusses on the pilot run of a simulation campaign aimed at investigating the spectroscopic capabilities of the Euclid NearInfrared Spectrometer and Photometer (NISP), in terms of continuum and emission line detection in the context of galaxy evo ...

EDP SCIENCES S A2023

DESI mock challenge Halo and galaxy catalogues with the bias assignment method

Cheng Zhao, Yu Yu, Ginevra Favole

Context. We present a novel approach to the construction of mock galaxy catalogues for large-scale structure analysis based on the distribution of dark matter halos obtained with effective bias models at the field level. Aims. We aim to produce mock galaxy ...

EDP SCIENCES S A2023

The DESI One-Percent Survey: Constructing Galaxy-Halo Connections for ELGs and LRGs Using Auto and Cross Correlations

Jiaxi Yu

In the current Dark Energy Spectroscopic Instrument (DESI) survey, emission line galaxies (ELGs) and luminous red galaxies (LRGs) are essential for mapping the dark matter distribution at < N(M)>. We measure the auto and cross correlation functions of ELGs ...

IOP Publishing Ltd2023

Probing the nature of Dark Energy through the study of large scale structures using spectroscopic surveys and their simulations

Andrei Variu

Measurements of large-scale structure (LSS), as performed on the largest 3D map of over two million extragalactic sources from the Sloan Digital Sky Survey, together with measurements of the cosmic microwave background (CMB) anisotropies, are in complete a ...

EPFL2023

Virgo Filaments. II. Catalog and First Results on the Effect of Filaments on Galaxy Properties

Pascale Jablonka, Gianluca Castignani

Virgo is the nearest galaxy cluster; it is thus ideal for studies of galaxy evolution in dense environments in the local universe. It is embedded in a complex filamentary network of galaxies and groups, which represents the skeleton of the large-scale Lani ...

IOP Publishing Ltd2022

ShapePipe: A new shape measurement pipeline and weak-lensing application to UNIONS/CFIS data

Austin Chandler Peel

Context. The Ultraviolet Near-Infrared Optical Northern Survey (UNIONS) is an ongoing collaboration that will provide the largest deep photometric survey of the northern sky in four optical bands to date. As part of this collaboration, the Canada-France Im ...

EDP SCIENCES S A2022

SEAGLE III: Towards resolving the mismatch in the dark-matter fraction in early-type galaxies between simulations and observations

Georgios Vernardos

The central dark-matter fraction of galaxies is sensitive to feedback processes during galaxy formation. Strong gravitational lensing has been effective in the precise measurement of the dark-matter fraction inside massive early-type galaxies. Here, we com ...

OXFORD UNIV PRESS2022

Nuclear star cluster formation in star-forming dwarf galaxies

Oliver Müller

Nuclear star clusters (NSCs) are massive star clusters found in all types of galaxies from dwarfs to massive galaxies. Recent studies show that while low-mass NSCs in dwarf galaxies (M-gal< 10(9)M(circle dot)) form predominantly out of the merger of globul ...

EDP SCIENCES S A2022

Next generation modeling techniques for strong gravitational lensing and measuring the Hubble constant

Aymeric Alexandre Galan

For many years, observations of the Universe suggest a series problems with our theoretical models, particularly its dark energy and dark matter components. Fortunately, the Universe also provides us with a tool to solve these problems, called strong gravi ...

EPFL2022

Stellar metallicity gradients of Local Group dwarf galaxies

Pascale Jablonka, Yves Revaz

Aims. We explore correlations between the strength of metallicity gradients in Local Group dwarf galaxies and their stellar mass, star formation history timescales, and environment. Methods. We performed a homogeneous analysis of literature spectroscopic d ...

2022

Advances in constraining intrinsic alignment models with hydrodynamic simulations

Jonathan Andrew Blazek

We use galaxies from the ILLUSTRISTNG, MASSIVEBLACK-II, and ILLUSTRTS-1 hydrodynamic simulations to investigate the behaviour of large scale galaxy intrinsic alignments. Our analysis spans four redshift slices over the approximate range of contemporary len ...

2021

Halo Mass-concentration Relation at the High-mass End

Jean-Paul Richard Kneib, Huanyuan Shan, Ginevra Favole

The concentration-mass (c-M) relation encodes key information about the assembly history of dark matter halos. However, its behavior at the high mass end has not been measured precisely in observations yet. In this paper, we report the measurement of the h ...

IOP Publishing Ltd2021

Tightening weak lensing constraints on the ellipticity of galaxy-scale dark matter haloes

Anand Stéphane Raichoor

Cosmological simulations predict that galaxies are embedded into triaxial dark matter haloes, which appear approximately elliptical in projection. Weak gravitational lensing allows us to constrain these halo shapes and thereby test the nature of dark matte ...

EDP SCIENCES S A2021

Virgo filaments I. Processing of gas in cosmological filaments around the Virgo cluster

Pascale Jablonka, Gianluca Castignani

It is now well established that galaxies have different morphologies, gas contents, and star formation rates (SFR) in dense environments like galaxy clusters. The impact of environmental density extends to several virial radii, and galaxies appear to be pr ...

EDP SCIENCES S A2021

On the influence of halo mass accretion history on galaxy properties and assembly bias

Ginevra Favole

Halo assembly bias is the secondary dependence of the clustering of dark matter haloes on their assembly histories at fixed halo mass. This established dependence is expected to manifest itself on galaxy clustering, a potential effect commonly known as gal ...

OXFORD UNIV PRESS2021