Publications related to Star | EPFL Graph Search

Evolution of the Size-Mass Relation of Star-forming Galaxies Since z=5.5 Revealed by CEERS

We combine deep imaging data from the CEERS early release JWST survey and Hubble Space Telescope imaging from CANDELS to examine the size-mass relation of star-forming galaxies and the morphology-quenching relation at stellar masses M-star >= 10(9.5)M(circ ...

Iop Publishing Ltd2024

GHOST commissioning science results - II: a very metal-poor star witnessing the early galactic assembly

Pascale Jablonka

This study focuses on Pristine_180956.78-294759.8 (hereafter P180956, [Fe/H] = -1.95 +/- 0.02), a star selected from the Pristine Inner Galaxy Survey (PIGS), and followed-up with the recently commissioned Gemini High-resolution Optical SpecTrograph (GHOST) ...

Oxford Univ Press2024

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

Stellar Metallicities and Gradients in the Isolated, Quenched Low-mass Galaxy Tucana

Nicolas Lawrence Etienne Longeard

We measure the metallicities of 374 red giant branch (RGB) stars in the isolated, quenched dwarf galaxy Tucana using Hubble Space Telescope (HST) narrow-band (F395N) Calcium H & K (CaHK) imaging. Our sample is a factor of similar to 7 similar to 7 larger t ...

Iop Publishing Ltd2024

Hidden Gems on a Ring: Infant Massive Clusters and Their Formation Timeline Unveiled by ALMA, HST, and JWST in NGC 3351

Robin Gopala Tress, Jiayi Sun, Hamid Hassani, Hao He

We use 0.1 '' observations from the Atacama Large Millimeter Array (ALMA), Hubble Space Telescope (HST), and JWST to study young massive clusters (YMCs) in their embedded "infant" phase across the central starburst ring in NGC 3351. Our new ALMA data revea ...

Iop Publishing Ltd2024

The Origins of Gas Accreted by Supermassive Black Holes: The Importance of Recycled Gas

Michaela Hirschmann

We investigate the fueling mechanisms of supermassive black holes (SMBHs) by analyzing 10 zoom-in cosmological simulations of massive galaxies, with stellar masses 1011-12 M circle dot and SMBH masses 108.9-9.7 M circle dot at z = 0, featuring various majo ...

Iop Publishing Ltd2024

The Complete CEERS Early Universe Galaxy Sample: A Surprisingly Slow Evolution of the Space Density of Bright Galaxies at z ∼ 8.5-14.5

Michaela Hirschmann

We present a sample of 88 candidate z similar to 8.5-14.5 galaxies selected from the completed NIRCam imaging from the Cosmic Evolution Early Release Science survey. These data cover similar to 90 arcmin2 (10 NIRCam pointings) in six broadband imaging filt ...

Iop Publishing Ltd2024

CLASSY. VIII. Exploring the Source of Ionization with UV Interstellar Medium Diagnostics in Local High-z Analogs

Adèle Marie Françoise Plat, Xinfeng Xu

In the current JWST era, rest-frame UV spectra play a crucial role in enhancing our understanding of the interstellar medium (ISM) and stellar properties of the first galaxies in the epoch of reionization (z > 6). Here, we compare well-known and reliable o ...

Iop Publishing Ltd2024

Extremely Red Galaxies at z=5-9 with MIRI and NIRSpec: Dusty Galaxies or Obscured Active Galactic Nuclei?

Michaela Hirschmann

We study a new population of extremely red objects (EROs) recently discovered by the James Webb Space Telescope (JWST) based on their NIRCam colors F277W - F444W > 1.5 mag. We find 37 EROs in the Cosmic Evolution Early Release Science Survey (CEERS) field ...

Iop Publishing Ltd2024

Weak gravitational lensing measurements of Abell 2744 using JWST and shear measurement algorithm pyRRG-JWST

David Richard Harvey, Richard Massey

We update the publicly available weak lensing shear measurement algorithm pyRRG for the JWST, and apply it to UNCOVER DR1 imaging of galaxy cluster Abell 2744. At short wavelengths (

Oxford Univ Press2024

Gaia's brightest very metal-poor (VMP) stars Metallicity catalogue of a thousand VMP stars from Gaia's radial velocity spectrometer spectra

Nicolas Lawrence Etienne Longeard

Context. Gaia DR3 has offered the scientific community a remarkable dataset of approximately one million spectra acquired with the radial velocity spectrometer (RVS) in the calcium II triplet region, which is well suited to identify very metal-poor (VMP) s ...

Edp Sciences S A2024

Small-amplitude Red Giants Elucidate the Nature of the Tip of the Red Giant Branch as a Standard Candle

Richard Irving Anderson, Nolan Wayne Koblischke

The tip of the red giant branch (TRGB) is an important standard candle for determining luminosity distances. Although several 105 small-amplitude red giant stars (SARGs) have been discovered, variability was previously considered irrelevant for the TRGB as ...

Iop Publishing Ltd2024

How much metal did the first stars provide to the ultra-faint dwarfs?

Pascale Jablonka, Yves Revaz, Mahsa Sanati

Numerical simulations of dwarf galaxies have so far failed to reproduce the observed metallicity-luminosity relation, down to the regime of ultra-faint dwarfs (UFDs). We address this issue by exploring how the first generations of metal-free stars (Pop III ...

EDP SCIENCES S A2023

Expanding on the fundamental metallicity relation in dwarf galaxies with MUSE

Oliver Müller

The mass-metallicity relation (MZR) represents one of the most important scaling relations in the context of galaxy evolution, comprising a positive correlation between stellar mass and metallicity (Z). The fundamental metallicity relation (FMR) introduces ...

Edp Sciences S A2023

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

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

Fuelling the nuclear ring of NGC 1097

Robin Gopala Tress, Jiayi Sun

Galactic bars can drive cold gas inflows towards the centres of galaxies. The gas transport happens primarily through the so-called bar dust lanes, which connect the galactic disc at kpc scales to the nuclear rings at hundreds of pc scales much like two gi ...

2023

The extended stellar halo' of the Ursa Minor dwarf galaxy

Pascale Jablonka

Stellar candidates in the Ursa Minor (UMi) dwarf galaxy have been found using a new Bayesian algorithm applied to Gaia EDR3 data. Five of these targets are located in the extreme outskirts of UMi, from similar to 5 to 12 elliptical half-light radii (r h), ...

OXFORD UNIV PRESS2023

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

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