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Martin Raoul Robert Millon

Cette personne a quitté l’EPFL

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Publications associées (28)

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Time-delay Cosmography with Strongly Lensed Quasars

Martin Raoul Robert Millon

The LCDM model has emerged as the concordance model of cosmology for its ability to explain a variety of observations, ranging from the anisotropies of the Cosmic Microwave Background (CMB) to the accelerated expansion of the Universe. However, with the ev ...

EPFL2021

Evidence for a milliparsec-separation supermassive binary black hole with quasar microlensing

Frédéric Courbin, Hung-Hsu Chan, Cameron Alexander Campbell Lemon, Martin Raoul Robert Millon, Eric Gérard Guy Paic

We report periodic oscillations in the 15-year-long optical light curve of the gravitationally lensed quasar Q J0158-4325 at z(s) = 1.29. The signal is enhanced during a high magnification microlensing event of the quasar that the fainter lensed image, B, ...

EDP SCIENCES S A2022

STRIDES: a 3.9 per cent measurement of the Hubble constant from the strong lens system DES J0408-5354

Frédéric Courbin, Georges Meylan, Vivien François Bonvin, Cameron Alexander Campbell Lemon, Martin Raoul Robert Millon, Aymeric Alexandre Galan

We present a blind time-delay cosmographic analysis for the lens system DES J0408-5354. This system is extraordinary for the presence of two sets of multiple images at different redshifts, which provide the opportunity to obtain more information at the cos ...

OXFORD UNIV PRESS2020

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

TDCOSMO. IV. Hierarchical time-delay cosmography - joint inference of the Hubble constant and galaxy density profiles

Frédéric Courbin, Martin Raoul Robert Millon, Aymeric Alexandre Galan

The H0LiCOWcollaboration inferred via strong gravitational lensing time delays a Hubble constant value of H0 = 73 :3+1:7 1:8 km s 1 Mpc 1, describing deflector mass density profiles by either a power-law or stars (constant mass-to-light ratio) plus standar ...

EDP SCIENCES S A2020

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

COSMOGRAIL XVII. Time delays for the quadruply imaged quasar PG 1115+080

Sun Hee Kim, Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Malte Tewes, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate, Eric Gérard Guy Paic

We present time-delay estimates for the quadruply imaged quasar PG 1115+080. Our results are based on almost daily observations for seven months at the ESO MPIA 2.2m telescope at La Silla Observatory, reaching a signal-to-noise ratio of about 1000 per quas ...

EDP SCIENCES S A2018

Probing compact dark matter objects with microlensing in gravitationally lensed quasars

Frédéric Courbin, Martin Raoul Robert Millon, Hung-Hsu Chan, Eric Gérard Guy Paic

The microlensing signal in the light curves of gravitationally lensed quasars can shed light on the dark matter (DM) composition in their lensing galaxies. Here, we investigate a sample of six lensed quasars from the most recent and best COSMOGRAIL observa ...

EDP SCIENCES S A2023

H0LiCOW-XIII. A 2.4 per cent measurement of H-0 from lensed quasars: 5.3 sigma tension between early- and late-Universe probes

Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon, Olga Tihhonova

We present a measurement of the Hubble constant (H-0) and other cosmological parameters from a joint analysis of six gravitationally lensed quasars with measured time delays. All lenses except the first are analysed blindly with respect to the cosmological ...

OXFORD UNIV PRESS2020

Constraining the microlensing effect on time delays with a new time-delay prediction model in H-0 measurements

Frédéric Courbin, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate

Time-delay strong lensing provides a unique way to directly measure the Hubble constant (H-0). The precision of the H-0 measurement depends on the uncertainties in the time-delay measurements, the mass distribution of the main deflector(s), and the mass di ...

OXFORD UNIV PRESS2018

A Microlensing Accretion Disk Size Measurement in the Lensed Quasar WFI 2026-4536

Frédéric Courbin, Vivien François Bonvin, Martin Raoul Robert Millon

We use 13 seasons of R-band photometry from the 1.2 m Leonard Euler Swiss Telescope at La Silla to examine microlensing variability in the quadruply imaged lensed quasar WFI 2026-4536. The lightcurves exhibit similar to 0.2 mag of uncorrelated variability ...

IOP PUBLISHING LTD2020

COSMOGRAIL: XIX. Time delays in 18 strongly lensed quasars from 15 years of optical monitoring star

Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Malte Tewes, Martin Raoul Robert Millon, Aymeric Alexandre Galan, Rémy Elie Joseph, Eric Gérard Guy Paic, Cameron Alexander Campbell Lemon, Olga Tihhonova

We present the results of 15 years of monitoring lensed quasars, which was conducted by the COSMOGRAIL programme at the Leonhard Euler 1.2 m Swiss Telescope. The decade-long light curves of 23 lensed systems are presented for the first time. We complement ...

EDP SCIENCES S A2020

TDCOSMO: I. An exploration of systematic uncertainties in the inference of H-0 from time-delay cosmography

Frédéric Courbin, Hung-Hsu Chan, Martin Raoul Robert Millon, Aymeric Alexandre Galan

Time-delay cosmography of lensed quasars has achieved 2.4% precision on the measurement of the Hubble constant, H0. As part of an ongoing effort to uncover and control systematic uncertainties, we investigate three potential sources: 1- stellar kinematics, ...

EDP SCIENCES S A2020

J1721+8842: a gravitationally lensed binary quasar with a proximate damped Lyman-alpha absorber

Frédéric Courbin, Martin Raoul Robert Millon, Hung-Hsu Chan, Eric Gérard Guy Paic, Cameron Alexander Campbell Lemon

High-redshift binary quasars provide key insights into mergers and quasar activity, and are useful tools for probing the spatial kinematics and chemistry of galaxies along the line of sight. However, only three sub-10-kpc binaries have been confirmed above ...

EDP SCIENCES S A2022

Strong gravitational lensing by AGNs as a probe of the quasar-host relations in the distant Universe

Frédéric Courbin, Malte Tewes, Martin Raoul Robert Millon, Aymeric Alexandre Galan

A rare case of a quasar acting as a gravitational lens allows a precise determination of the mass of the quasar's host galaxy and offers a new path to studying the connections between supermassive black holes and their host galaxies. ...

NATURE PORTFOLIO2023

Accretion Disk Size and Updated Time-delay Measurements in the Gravitationally Lensed Quasar SDSS J165043.44+425149.3

Frédéric Courbin, Martin Raoul Robert Millon

We analyze variability in 15-season optical lightcurves from the doubly imaged lensed quasar SDSS J165043.44+425149.3 (SDSS1650), comprising five seasons of monitoring data from the Maidanak Observatory (277 nights in total, including the two seasons of da ...

Iop Publishing Ltd2024

STRIDES: automated uniform models for 30 quadruply imaged quasars

Frédéric Courbin, Cameron Alexander Campbell Lemon, Martin Raoul Robert Millon

Gravitational time delays provide a powerful one-step measurement of H-0, independent of all other probes. One key ingredient in time-delay cosmography are high-accuracy lens models. Those are currently expensive to obtain, both, in terms of computing and ...

OXFORD UNIV PRESS2023

COSMOGRAIL XVIII. time delays of the quadruply lensed quasar WFI2033-4723

Sun Hee Kim, Frédéric Courbin, Georges Meylan, Hung-Hsu Chan, Vivien François Bonvin, Malte Tewes, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate

We present new measurements of the time delays of WFI2033-4723. The data sets used in this work include 14 years of data taken at the 1.2 m Leonhard Euler Swiss telescope, 13 years of data from the SMARTS 1.3 m telescope at Las Campanas Observatory and a s ...

2019

Time delay lens modelling challenge

Frédéric Courbin, Vivien François Bonvin, Martin Raoul Robert Millon, Aymeric Alexandre Galan

In recent years, breakthroughs in methods and data have enabled gravitational time delays to emerge as a very powerful tool to measure the Hubble constant H-0. However, published state-of-the-art analyses require of order 1 yr of expert investigator time a ...

OXFORD UNIV PRESS2021

Measuring accretion disk sizes of lensed quasars with microlensing time delay in multi-band light curves

Frédéric Courbin, Hung-Hsu Chan, Vivien François Bonvin, Martin Raoul Robert Millon, Karina Alexandra Rojas Olate

Time-delay cosmography in strongly lensed quasars offers an independent way of measuring the Hubble constant, H-0. However, it has been proposed that the combination of microlensing and source-size effects, also known as microlensing time delay, can potent ...

EDP SCIENCES S A2021