Aymeric Alexandre Galan

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Challenges inherent to high-resolution and high signal-to-noise data as well as model degeneracies can cause systematic biases in analyses of strong lens systems. In the past decade, the number of lens modeling methods has significantly increased, from pur ...

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 ...

We present our search for strong lens, galaxy-scale systems in the first data release of the Dark Energy Survey (DES), based on a color-selected parent sample of 18 745 029 luminous red galaxies (LRGs). We used a convolutional neural network (CNN) to grade ...

Strong gravitational lensing is a powerful tool to provide constraints on galaxy mass distributions and cosmological parameters, such as the Hubble constant, H0. Nevertheless, inference of such parameters from images of lensing systems is not trivial as pa ...

We present the proof of concept of a method for finding strongly lensed quasars using their spatially extended photometric variability through difference imaging in cadenced imaging survey data. We applied the method to Pan-STARRS, starting with an initial ...

The importance of alternative methods for measuring the Hubble constant, such as time-delay cosmography, is highlighted by the recent Hubble tension. It is paramount to thoroughly investigate and rule out systematic biases in all measurement methods before ...

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. ...

We present new time delays, the main ingredient of time delay cosmography, for 22 lensed quasars resulting from high-cadence r-band monitoring on the 2.6 m ESO VLT Survey Telescope and Max-Planck-Gesellschaft 2.2 m telescope. Each lensed quasar was typical ...

In the context of gravitational lensing, the density profile of lensing galaxies is often considered to be perfectly elliptical. Potential angular structures are generally ignored, except to explain flux ratios of point-like sources (i.e. flux ratio anomal ...

One of the main challenges in using high-redshift active galactic nuclei (AGNs) to study the correlations between the mass of a supermassive black hole (M-BH) and the properties of its active host galaxy is instrumental resolution. Strong lensing magnifica ...

We present a new active contour to segment cell aggregates. We describe it by a smooth tessellation that is attracted toward the cell membranes. Our approach relies on subdivision schemes that are tightly linked to the theory of wavelets. The shape is enco ...

Aymeric Alexandre Galan

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Exploiting the diversity of modeling methods to probe systematic biases in strong lensing analyses

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

Search of strong lens systems in the Dark Energy Survey using convolutional neural networks

Accelerating galaxy dynamical modeling using a neural network for joint lensing and kinematic analyses

Nine lensed quasars and quasar pairs discovered through spatially extended variability in Pan-STARRS

IX. Systematic comparison between lens modelling software programs:Time-delay prediction for WGD 2038-4008

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

Tdcosmo Xvii. New Time Delays in 22 Lensed Quasars From Optical Monitoring with the Eso-vst 2.6m and Mpg 2.2m Telescopes

TDCOSMO VII. Boxyness/discyness in lensing galaxies: Detectability and impact on H-0

Testing the evolution of correlations between supermassive black holes and their host galaxies using eight strongly lensed quasars

Deforming Tessellations for the Segmentation of Cell Aggregates