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Concept

Astronomie extragalactique

Publications associées (13)

COSMOS-Web: Intrinsically Luminous z ≳ 10 Galaxy Candidates Test Early Stellar Mass Assembly

Michaela Hirschmann

We report the discovery of 15 exceptionally luminous 10 less than or similar to z less than or similar to 14 candidate galaxies discovered in the first 0.28 deg(2) of JWST/NIRCam imaging from the COSMOS-Web survey. These sources span rest-frame UV magnitud ...

Iop Publishing Ltd2024

Gaia Data Release 3: The extragalactic content

Richard Irving Anderson, Shuangqing Liao, Mária Süveges, Pablo Jose Fernandez Marcos

The Gaia Galactic survey mission is designed and optimized to obtain astrometry, photometry, and spectroscopy of nearly two billion stars in our Galaxy. Yet as an all-sky multi-epoch survey, Gaia also observes several million extragalactic objects down to ...

2023

Spectral Templates Optimal for Selecting Galaxies at z > 8 with the JWST

Michaela Hirschmann

The selection of high-redshift galaxies often involves spectral energy distribution (SED) fitting to photometric data, an expectation for contamination levels, and measurement of sample completeness-all vetted through comparison to spectroscopic redshift m ...

Iop Publishing Ltd2023

Gaia Focused Product Release: Spatial distribution of two diffuse interstellar bands

Stephan Morgenthaler, Shuangqing Liao

Diffuse interstellar bands (DIBs) are absorption features seen in optical and infrared spectra of stars and extragalactic objects that are probably caused by large and complex molecules in the galactic interstellar medium (ISM). Here we investigate the Gal ...

Edp Sciences S A2023

CEERS Key Paper. VI. JWST/MIRI Uncovers a Large Population of Obscured AGN at High Redshifts

Michaela Hirschmann

Mid-infrared (mid-IR) observations are powerful in identifying heavily obscured active galactic nuclei (AGN) that have weak emission in other wavelengths. Data from the Mid-Infrared Instrument (MIRI) on board the James Webb Space Telescope provides an exce ...

2023

Near-infrared emission line diagnostics for AGN from the local Universe to z ∼ 3

Michaela Hirschmann

Optical rest-frame spectroscopic diagnostics are usually employed to distinguish between star formation and active galactic nucleus (AGN) powered emission. However, this method is biased against dusty sources, hampering a complete census of the AGN populat ...

Edp Sciences S A2023

Euclid preparation - XXIII. Derivation of galaxy physical properties with deep machine learning using mock fluxes and H-band images

Maurizio Martinelli, Robin Humphry-Baker, Frédéric Courbin, Georges Meylan, Gianluca Castignani, Austin Chandler Peel

Next-generation telescopes, like Euclid, Rubin/LSST, and Roman, will open new windows on the Universe, allowing us to infer physical properties for tens of millions of galaxies. Machine-learning methods are increasingly becoming the most efficient tools to ...

OXFORD UNIV PRESS2023

Resolving Galactic-scale Obscuration of X-Ray AGNs at z & GSIM; 1 with COSMOS-Web

Michaela Hirschmann

A large fraction of the accreting supermassive black hole population is shrouded by copious amounts of gas and dust, particularly in the distant (z & GSIM; 1) universe. While much of the obscuration is attributed to a parsec-scale torus, there is a known c ...

IOP Publishing Ltd2023

SEEDisCS: I. Molecular gas in galaxy clusters and their large-scale structure: The case of CL1411.1-1148 at z similar to 0.5

Pascale Jablonka, Gianluca Castignani, Damien Louis Alexandre Spérone-Longin

We investigate how the galaxy reservoirs of molecular gas fuelling star formation are transformed while the host galaxies infall onto galaxy cluster cores. As part of the Spatially Extended ESO Distant Cluster Survey (SEEDisCS), we present CO(3-2) observat ...

EDP SCIENCES S A2021

The Spitzer-Irac/Mips Extragalactic Survey (Simes) In The South Ecliptic Pole Field

Hakim Atek

We present the Spitzer-IRAC/MIPS Extragalactic survey (SIMES) in the South Ecliptic Pole field. The large area covered (7.7 deg(2)), together with one of the lowest Galactic cirrus emissions in the entire sky and a very extensive coverage by Spitzer, Hersc ...

Iop Publishing Ltd2016

Planck 2013 results. XI. All-sky model of thermal dust emission

Julien Lesgourgues

This paper presents an all-sky model of dust emission from the Planck 353, 545, and 857 GHz, and IRAS 100 mu m data. Using a modified blackbody fit to the data we present all-sky maps of the dust optical depth, temperature, and spectral index over the 353- ...

Edp Sciences S A2014

Manganese in dwarf spheroidal galaxies

Pascale Jablonka, Pierre North

We provide manganese abundances (corrected for the effect of the hyperfine structure) for a large number of stars in the dwarf spheroidal galaxies Sculptor and Fornax, and for a smaller number in the Carina and Sextans dSph galaxies. Abundances had already ...

2012

Astrophysical applications of gravitationally lensed quasars : from dark matter halos to the structure of quasar accretion disks

Alexander Patrick Eigenbrod

Gravitational lensing describes how light is deflected as it passes in the vicinity of a mass distribution. The amplitude of the deflection is proportional to the mass of the deflector, called "gravitational lens", and is generally weak, even for large mas ...

EPFL2008