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Concept

Télescope spatial

Publications associées (23)

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

David Richard Harvey

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

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

Single-Photon Avalanche Diode Image Sensors for Harsh Radiation Environments

Ming-Lo Wu

The space industry has experienced substantial growth in recent years, leading to rapid advancements in space exploration and space-based technologies. Consequently, the study of electronics and sensor performance in extreme environments has become crucial ...

EPFL2024

Direct Data-Driven Vibration Control for Adaptive Optics

Alireza Karimi, Vaibhav Gupta

Adaptive optics (AO) systems are used in ground- based telescopes to improve image resolutions, especially for long-exposure photography, by compensating for the effects of atmospheric turbulence and internal vibrations. Most current AO systems are based o ...

2023

An Atlas of Color-selected Quiescent Galaxies at z > 3 in Public JWST Fields

Michaela Hirschmann, Minju Lee

We present the results of a systematic search for candidate quiescent galaxies in the distant universe in 11 JWST fields with publicly available observations collected during the first 3 months of operations and covering an effective sky area of similar to ...

IOP Publishing Ltd2023

A Long Time Ago in a Galaxy Far, Far Away: A Candidate z similar to 12 Galaxy in Early JWST CEERS Imaging

Michaela Hirschmann

We report the discovery of a candidate galaxy with a photo -z of z similar to 12 in the first epoch of the James Webb Space Telescope (JWST) Cosmic Evolution Early Release Science Survey. Following conservative selection criteria, we identify a source with ...

IOP Publishing Ltd2022

Metallicity Distribution Function of the Eridanus II Ultra-faint Dwarf Galaxy from Hubble Space Telescope Narrowband Imaging

Nicolas Lawrence Etienne Longeard

We use deep narrowband CaHK (F395N) imaging taken with the Hubble Space Telescope (HST) to construct the metallicity distribution function (MDF) of Local Group ultra-faint dwarf galaxy Eridanus II (Eri II). When combined with archival F475W and F814W data, ...

IOP Publishing Ltd2022

Strong lensing in UNIONS: Toward a pipeline from discovery to modeling

Frédéric Courbin, Hung-Hsu Chan, Cameron Alexander Campbell Lemon, Georgios Vernardos, Benjamin Yvan Alexandre Clement, Karina Alexandra Rojas Olate, Elodie Marie Charlène Savary

We present a search for galaxy-scale strong gravitational lenses in the initial 2500 square degrees of the Canada-France Imaging Survey (CFIS). We designed a convolutional neural network (CNN) committee that we applied to a selection of 2 344 002 r-band im ...

EDP SCIENCES S A2022

Towards quantum 3D imaging devices

Edoardo Charbon, Claudio Bruschini, Samuel Burri, Arin Can Ülkü, Paul Mos, Michael Alan Wayne

We introduce a new generation of 3D imaging devices based on quantum plenoptic imaging. Position-momentum entanglement and photon number correlations are exploited to provide a scan-free 3D image after post-processing of the collected light intensity signa ...

2021

H0LiCOW-XI. A weak lensing measurement of the external convergence in the field of the lensed quasar B1608+656 using HST and Subaru deep imaging

Frédéric Courbin, Georges Meylan, Vivien François Bonvin, David Richard Harvey, Austin Chandler Peel, Olga Tihhonova

We investigate the environment and line of sight (LoS) of the H0LiCOW (H-0 Lenses in COSMOGRAIL's Wellspring) lens B1608+656 using Subaru Suprime-Cam and the Hubble Space Telescope (HST) to perform a weak lensing analysis. We compare three different method ...

OXFORD UNIV PRESS2020

A SHARP view of H0LiCOW: H-0 from three time-delay gravitational lens systems with adaptive optics imaging

Frédéric Courbin, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon

We present the measurement of the Hubble constant, H-0, with three strong gravitational lens systems, We describe a blind analysis of both PG 1115+080 and 11E0435-1223 as well as an extension of our previous analysis of RXJ 1131-1231. For each lens, we com ...

OXFORD UNIV PRESS2019

Evaluating the effect of stellar multiplicity on the point spread function of space-based weak lensing surveys

Frédéric Courbin, Georges Meylan, Thibault Adrien Kuntzer

The next generation of space-based telescopes used for weak lensing surveys will require exquisite point spread function (PSF) determination. Previously negligible effects may become important in the reconstruction of the PSF, in part because of the improv ...

Edp Sciences S A2016

Stellar classification from single-band imaging using machine learning

Frédéric Courbin, Malte Tewes, Thibault Adrien Kuntzer

Information on the spectral types of stars is of great interest in view of the exploitation of space-based imaging surveys. In this article, we investigate the classification of stars into spectral types using only the shape of their diffraction pattern in ...

Edp Sciences S A2016

The Lyman alpha reference sample VII. Spatially resolved H alpha kinematics

Hakim Atek

We present integral field spectroscopic observations with the Potsdam Multi-Aperture Spectrophotometer of all 14 galaxies in the z similar to 0.1 Lyman Alpha Reference Sample (LARS). We produce 2D line-of-sight velocity maps and velocity dispersion maps fr ...

Edp Sciences S A2016

The nongravitational interactions of dark matter in colliding galaxy clusters

David Richard Harvey

Collisions between galaxy clusters provide a test of the nongravitational forces acting on dark matter. Dark matter's lack of deceleration in the "bullet cluster" collision constrained its self-interaction cross section sigma(DM)/m

American Association for the Advancement of Science2015

The Lyman Alpha Reference Sample. Ii. Hubble Space Telescope Imaging Results, Integrated Properties, And Trends

Hakim Atek

We report new results regarding the Ly alpha output of galaxies, derived from the Lyman Alpha Reference Sample, and focused on Hubble Space Telescope imaging. For 14 galaxies we present intensity images in Ly alpha, H alpha, and UV, and maps of H alpha/H b ...

American Astronomical Society2014

Unidentified Line in X-Ray Spectra of the Andromeda Galaxy and Perseus Galaxy Cluster

Alexey Boyarsky, Oleg Ruchayskiy

We report a weak line at 3.52 +/- 0.02 keV in x-ray spectra of the Andromeda galaxy and the Perseus galaxy cluster observed by the metal-oxide-silicon (MOS) and p-n (PN) CCD cameras of the XMM-Newton telescope. This line is not known as an atomic line in t ...

Amer Physical Soc2014

Probing the z> 6 universe with the first Hubble frontier fields cluster A2744

Jean-Paul Richard Kneib, Hakim Atek, Benjamin Yvan Alexandre Clement

The Hubble Frontier Fields program combines the capabilities of the Hubble Space Telescope (HST) with the gravitational lensing of massive galaxy clusters to probe the distant universe to an unprecedented depth. Here, we present the results of the first co ...

American Astronomical Society2014

Mass and magnification maps for the Hubble Space Telescope Frontier Fields clusters: implications for high-redshift studies

Jean-Paul Richard Kneib, Hakim Atek, Benjamin Yvan Alexandre Clement

Extending over three Hubble Space Telescope (HST) cycles, the Hubble Frontier Fields (HFF) initiative constitutes the largest commitment ever of HST time to the exploration of the distant Universe via gravitational lensing by massive galaxy clusters. Here, ...

Wiley-Blackwell2014

A 7 deg(2) survey for galaxy-scale gravitational lenses with the HST imaging archive(star)

Frédéric Courbin, Georges Meylan

We present the results of a visual search for galaxy-scale gravitational lenses in similar to 7 deg(2) of Hubble Space Telescope (HST) images. The data set comprises the whole imaging data ever taken with the Advanced Camera for Surveys (ACS) in the filter ...

Wiley-Blackwell2014