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Concept

Système photométrique

Publications associées (27)

Euclid preparation XXXVII. Galaxy colour selections with Euclid and ground photometry for cluster weak-lensing analyses

Maurizio Martinelli, Frédéric Courbin, Georges Meylan, Gianluca Castignani, Matthias Wiesmann

Aims. We derived galaxy colour selections from Euclid and ground-based photometry, aiming to accurately define background galaxy samples in cluster weak-lensing analyses. These selections have been implemented in the Euclid data analysis pipelines for gala ...

Edp Sciences S A2024

Euclid: The search for primordial features

Yiming Li, Frédéric Courbin, Georges Meylan

Primordial features, in particular oscillatory signals, imprinted in the primordial power spectrum of density perturbations represent a clear window of opportunity for detecting new physics at high-energy scales. Future spectroscopic and photometric measur ...

Edp Sciences S A2024

MOSEL Survey: JWST Reveals Major Mergers/strong Interactions Drive the Extreme Emission Lines in the Early Universe

Michaela Hirschmann

Extreme emission line galaxies (EELGs), where nebular emissions contribute 30%-40% of the flux in certain photometric bands, are ubiquitous in the early Universe (z > 6). We utilize deep NIRCam imaging from the JWST Advanced Deep Extragalactic Survey (JADE ...

Iop Publishing Ltd2023

Detailed asteroseismic modelling of RR Lyrae stars with non-radial modes

Henryka Ewa Netzel

Photometric observations from the last decade have revealed additional low-amplitude periodicities in many classical pulsators that are likely due to pulsations in non-radial modes. One group of multimode RR Lyrae stars, the so-called 0.61 stars, is partic ...

Oxford Univ Press2023

Potential scientific synergies in weak lensing studies between the CSST and Euclid space probes

Jean-Paul Richard Kneib, Huanyuan Shan

Aims. With the next generation of large surveys poised to join the ranks of observational cosmology in the near future, it is important to explore their potential synergies and to maximize their scientific outcomes. In this study, we aim to investigate the ...

EDP SCIENCES S A2023

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

The Pristine survey - XX. GTC follow-up observations of extremely metal-poor stars identified from Pristine and LAMOST

Pascale Jablonka

A B S T R A C T Ultra-metal-poor stars ( [Fe / H] < -4 . 0) are very rare, and finding them is a challenging task. Both narrow-band photometry and low-resolution spectroscopy have been useful tools for identifying candidates, and in this work, we combine b ...

OXFORD UNIV PRESS2023

Constraining quasar structure using high-frequency microlensing variations and continuum reverberation

Frédéric Courbin, Vivien François Bonvin, Martin Raoul Robert Millon, Hung-Hsu Chan, Georgios Vernardos, Eric Gérard Guy Paic

Gravitational microlensing is a powerful tool for probing the inner structure of strongly lensed quasars and for constraining parameters of the stellar mass function of lens galaxies. This is achieved by analysing microlensing light curves between the mult ...

EDP SCIENCES S A2022

Baryon acoustic oscillations in the projected cross-correlation function between the eBOSS DR16 quasars and photometric galaxies from the DESI Legacy Imaging Surveys

Cheng Zhao, Anand Stéphane Raichoor

We search for the baryon acoustic oscillations in the projected cross-correlation function binned into transverse comoving radius between the SDSS-IV DR16 eBOSS quasars and a dense photometric sample of galaxies selected from the DESI Legacy Imaging Survey ...

OXFORD UNIV PRESS2021

The formation of the milky way halo and its dwarf satellites: a NLTE-1D abundance analysis. IV. Segue 1, Triangulumii, and Coma Berenices UFDs

Pascale Jablonka

We present atmospheric parameters and abundances for chemical elements from carbon to barium in metal-poor stars in Segue 1 (seven stars), Coma Berenices (three stars), and Triangulum II (one star) ultrafaint dwarf galaxies (UFDs). The effective temperatur ...

OXFORD UNIV PRESS2021

The Pristine survey XI: the FORS2 sample

Pascale Jablonka, Carmela Lardo

Extremely metal-poor (EMP) stars are old objects that mostly formed very early after the big bang. They are rare and, to select them, we have to rely on low-resolution spectroscopic or photometric surveys; specifically the combination of narrow- and broad- ...

OXFORD UNIV PRESS2020

The Pristine Survey - VIII. The metallicity distribution function of the Milky Way halo down to the extremely metal-poor regime

Pascale Jablonka, Carmela Lardo

The Pristine survey uses narrow-band photometry to derive precise metallicities down to the extremely metal-poor regime ([Fe/H]

OXFORD UNIV PRESS2020

The Sloan Digital Sky Survey Reverberation Mapping Project: Initial CIV Lag Results from Four Years of Data

Jean-Paul Richard Kneib, Feng Li

We present reverberation-mapping (RM) lags and black hole mass measurements using the C IV lambda 1549 broad emission line from a sample of 348 quasars monitored as a part of the Sloan Digital Sky Survey RM Project. Our data span four years of spectroscopi ...

IOP PUBLISHING LTD2019

Phenotypic redshifts with self-organizing maps: A novel method to characterize redshift distributions of source galaxies for weak lensing

Eduardo Sanchez, Romain Buchs

Wide-field imaging surveys such as the Dark Energy Survey (DES) rely on coarse measurements of spectral energy distributions in a few filters to estimate the redshift distribution of source galaxies. In this regime, sample variance, shot noise, and selecti ...

2019

Constant light element abundances suggest that the extended P1 in NGC 2808 is not a consequence of CNO-cycle nucleosynthesis

Carmela Lardo

Recent photometric results have identified a new population among globular cluster stars. This population, referred to as the 'extended P1', has been suggested to be the manifestation of a new abundance pattern where the initial mass fraction of He changes ...

OXFORD UNIV PRESS2019

H0LiCOW-IX. Cosmographic analysis of the doubly imaged quasar SDSS 1206+4332 and a new measurement of the Hubble constant

Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Riccardo Agnello, Vivien François Bonvin

We present a blind time-delay strong lensing (TDSL) cosmographic analysis of the doubly imaged quasar SDSS 1206+4332. We combine the relative time delay between the quasar images, Hubble Space Telescope imaging, the Keck stellar velocity dispersion of the ...

OXFORD UNIV PRESS2019

Euclid preparation III. Galaxy cluster detection in the wide photometric survey, performance and algorithm selection

Gianluca Castignani, Marina Ricci, Adam Julian Richardson

Galaxy cluster counts in bins of mass and redshift have been shown to be a competitive probe to test cosmological models. This method requires an efficient blind detection of clusters from surveys with a well-known selection function and robust mass estima ...

EDP Sciences2019

The SDSS-IV eBOSS: emission line galaxy catalogues at z approximate to 0.8 and study of systematic errors in the angular clustering

Jean-Paul Richard Kneib, Xiaoqing Zhou, Anand Stéphane Raichoor, Timothée Guy Olivier Delubac

We present two wide-field catalogues of photometrically selected emission line galaxies (ELGs) at z approximate to 0.8 covering about 2800 deg(2)over the south galactic cap. The catalogues were obtained using a Fisher discriminant technique described in a ...

Oxford Univ Press2017

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

Gaia Data Release 1 Summary of the astrometric, photometric, and survey properties

Stephan Morgenthaler, Shuangqing Liao

Context. At about 1000 days after the launch of Gaia we present the first Gaia data release, Gaia DR1, consisting of astrometry and photometry for over 1 billion sources brighter than magnitude 20.7. Aims. A summary of Gaia DR1 is presented along with illu ...

EDP Sciences2016