Publications

Publications


Rethinking data-driven point spread function modeling with a differentiable optical model

  Authors: Tobias Liaudat, Jean-Luc Starck, Martin Kilbinger, Pierre-Antoine Frugier Journal: Inverse Problems Year: 2023 DOI:   Download: ADS | arXiv...
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Deep Learning-based galaxy image deconvolution

  Authors: Utsav Akhaury, Jean-Luc Starck, Pascale Jablonka, Frédéric Courbin, Kevin Michalewicz Journal: A&A Year: 2022 DOI:   Download: ADS | arXiv Abstract With the...
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UNIONS: The impact of systematic errors on weak-lensing peak counts

  Authors: E. Ayçoberry, V. Ajani, A. Guinot, M. Kilbinger, V. Pettorino, S. Farrens, J.-L. Starck, R. Gavazzi, M. Hudson...
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UNIONS: The impact of systematic errors on weak-lensing peak counts

ShapePipe: a new shape measurement pipeline and weak-lensing application to UNIONS/CFIS data

  Authors: A. Guinot, M. Kilbinger, S. Farrens, A. Peel, A. Pujol, M. Schmitz, J.-L. Starck, T. Erben, R. Gavazzi,...
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ShapePipe: a new shape measurement pipeline and weak-lensing application to UNIONS/CFIS data

ShapePipe: A modular weak-lensing processing and analysis pipeline

  Authors: S. Farrens, A. Guinot, M. Kilbinger, T. Liaudat , L. Baumont, X. Jimenez, A. Peel , A. Pujol...
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ShapePipe: A modular weak-lensing processing and analysis pipeline


  •   Authors: Tobias Liaudat, Jean-Luc Starck, Martin Kilbinger, Pierre-Antoine Frugier Journal: Inverse Problems Year: 2023 DOI:   Download: ADS | arXiv Abstract In astronomy, upcoming space telescopes with wide-field optical instruments have a spatially varying point spread function (PSF). Specific scientific goals require a high-fidelity estimation of the PSF at target positions where no direct measurement

  •   Authors: Utsav Akhaury, Jean-Luc Starck, Pascale Jablonka, Frédéric Courbin, Kevin Michalewicz Journal: A&A Year: 2022 DOI:   Download: ADS | arXiv Abstract With the onset of large-scale astronomical surveys capturing millions of images, there is an increasing need to develop fast and accurate deconvolution algorithms that generalize well to different images. A powerful and accessible deconvolution method would allow

  •   Authors: E. Ayçoberry, V. Ajani, A. Guinot, M. Kilbinger, V. Pettorino, S. Farrens, J.-L. Starck, R. Gavazzi, M. Hudson Journal: A&A Year: 2022 DOI:   Download: ADS | arXiv Abstract Context. The Ultraviolet Near-Infrared Optical Northern Survey (UNIONS) is an ongoing deep photometric multi-band survey of the Northern sky. As part of UNIONS, the Canada-France

  •   Authors: A. Guinot, M. Kilbinger, S. Farrens, A. Peel, A. Pujol, M. Schmitz, J.-L. Starck, T. Erben, R. Gavazzi, S. Gwyn, M. Hudson,  H. Hiledebrandt, T. Liaudat , et. al Journal: A&A Year: 2022 DOI:   Download: ADS | arXiv Abstract UNIONS is an ongoing collaboration that will provide the largest deep photometric survey of

  •   Authors: S. Farrens, A. Guinot, M. Kilbinger, T. Liaudat , L. Baumont, X. Jimenez, A. Peel , A. Pujol , M. Schmitz, J.-L. Starck, and A. Z. Vitorelli Journal: A&A Year: 2022 DOI: 10.1051/0004-6361/202243970 Download: ADS | arXiv Abstract We present the first public release of ShapePipe, an open-source and modular weak-lensing measurement, analysis, and

  •   Authors: L. Ingoglia, G. Covone, M. Sereno, …, S. Farrens, et al. Journal: MNRAS Year: 2022 DOI: 10.1093/mnras/stac046 Download: ADS | arXiv Abstract Galaxy clusters are biased tracers of the underlying matter density field. At very large radii beyond about 10 Mpc/\textit{h}, the shear profile shows evidence of a second-halo term. This is related to

  • Early dark energy in the pre- and postrecombination epochs  Authors:   Adrià Gómez-Valent, Ziyang Zheng, Luca Amendola, Valeria Pettorino, Christof Wetterich Journal: PRD Year: 07/2021 Download: PRD | Arxiv Abstract Dark energy could play a role at redshifts z≫O(1). Many quintessence models possess scaling or attractor solutions where the fraction of dark energy follows the dominant component in previous epochs

  •   Authors: S. Farrens, A. Lacan, A. Guinot, A. Z. Vitorelli Journal: A&A Year: 2022 DOI: 10.1051/0004-6361/202141166 Download: ADS | arXiv Abstract We present BlendHunter, a proof-of-concept deep-transfer-learning-based approach for the automated and robust identification of blended sources in galaxy survey data. We take the VGG-16 network with pre-trained convolutional layers and train the fully connected

  • Deep Learning has become a very promising avenue for magnetic resonance image (MRI) reconstruction. In this work, we explore the potential of unrolled networks for the non-Cartesian acquisition setting. We design the NC-PDNet, the first density-compensated unrolled network and validate the need for its key components via an ablation study. Moreover, we conduct some generalizability

  • Deep neural networks have recently been thoroughly investigated as a powerful tool for MRI reconstruction. There is a lack of research, however, regarding their use for a specific setting of MRI, namely non-Cartesian acquisitions. In this work, we introduce a novel kind of deep neural networks to tackle this problem, namely density compensated unrolled neural

  • Starlet l1-norm for weak lensing cosmology  Authors: Virginia Ajani, Jean-Luc Starck, Valeria Pettorino Journal: Astronomy & Astrophysics , Forthcoming article, Letters to the Editor Year: 01/2021 Download: A&A| Arxiv Abstract We present a new summary statistic for weak lensing observables, higher than second order, suitable for extracting non-Gaussian cosmological information and inferring cosmological parameters. We

  • Accelerating MRI scans is one of the principal outstanding problems in the MRI research community. Towards this goal, we hosted the second fastMRI competition targeted towards reconstructing MR images with subsampled k-space data. We provided participants with data from 7,299 clinical brain scans (de-identified via a HIPAA-compliant procedure by NYU Langone Health), holding back the

  • Sparse Blind Source Separation (sBSS) plays a key role in scientific domains as different as biomedical imaging, remote sensing or astrophysics, which require the development of increasingly faster and scalable BSS methods without sacrificing the separation performances. To that end, a new distributed sparse BSS algorithm is introduced based on a mini-batch ex-tension of the

  • Context. Galaxy imaging surveys observe a vast number of objects that are affected by the instrument’s Point Spread Function (PSF). Weak lensing missions, in particular, aim at measuring the shape of galaxies, and PSF effects represent an important source of systematic errors which must be handled appropriately. This demands a high accuracy in the modelling

  • The Dark Matter present in the Large-Scale Structure of the Universe is invisible, but its presence can be inferred through the small gravitational lensing effect it has on the images of far away galaxies. By measuring this lensing effect on a large number of galaxies it is possible to reconstruct maps of the Dark Matter

  • We present a modular cross-domain neural network the XPDNet and its application to the MRI reconstruction task. This approach consists in unrolling the PDHG algorithm as well as learning the acceleration scheme between steps. We also adopt state-of-the-art techniques specific to Deep Learning for MRI reconstruction. At the time of writing, this approach is the

  • Deep neural networks have proven extremely efficient at solving a wide range of inverse problems, but most often the uncertainty on the solution they provide is hard to quantify. In this work, we propose a generic Bayesian framework for solving inverse problems, in which we limit the use of deep neural networks to learning a

  • Sparsity based methods, such as wavelets, have been state-of-the-art for more than 20 years for inverse problems before being overtaken by neural networks. In particular, U-nets have proven to be extremely effective. Their main ingredients are a highly non-linear processing, a massive learning made possible by the flourishing of optimization algorithms with the power of

  •   The MRI reconstruction field lacked a proper data set that allowed for reproducible results on real raw data (i.e. complex-valued), especially when it comes to deep learning (DL) methods as this kind of approaches require much more data than classical Compressed Sensing~(CS) reconstruction. This lack is now filled by the fastMRI data set, and

  • Reference:  Z. Ramzi, P. Ciuciu and J.-L. Starck. “Benchmarking proximal methods acceleration enhancements for CS-acquired MR image analysis reconstruction”, SPARS, 2019 Code ModOpt

  • Effect of nonlinear prescriptions

    Euclid: impact of nonlinear prescriptions on cosmological parameter estimation from weak lensing cosmic shear   Authors: Martinelli, M.;Tutusaus, I.;Archidiacono, M.;Camera, S.;Cardone, V. F.;Clesse, S.;Casas, S.;Casarini, L.;Mota, D. F.;Hoekstra, H.;Carbone, C.;Ilić, S.;Kitching, T. D.;Pettorino, V.;Pourtsidou, A.;Sakr, Z.;Sapone, D.; et al. Journal:   Year: 10/2020 Download: Inspire| Arxiv Abstract Upcoming surveys will map the growth of large-scale

  • Euclid: impact of nonlinear prescriptions on cosmological parameter estimation from weak lensing cosmic shear   Authors: Euclid Collaboration;Blanchard, A.;Camera, S.;Carbone, C.;Cardone, V. F.;Casas, S.;Clesse, S.;Ilić, S.;Kilbinger, M.;Kitching, T.;Kunz, M.;Lacasa, F.;Linder, E.;Majerotto, E.;Markovič, K.;Martinelli, M.;Pettorino, V.;Pourtsidou, A.;Sakr, Z.;Sánchez, A. G.;Sapone, D.;Tutusaus, I.;Yahia-Cherif, S.;Yankelevich, V.;et al. Journal: Astronomy & Astrophysics, Volume 642, id.A191, 66 pp. Year: 10/2020

  •   Authors: I.P. Carucci, M.O. Irfan, J.Bobin Journal: MNRAS Year: 2020 Download: ADS | arXiv 21 cm intensity mapping has emerged as a promising technique to map the large-scale structure of the Universe. However, the presence of foregrounds with amplitudes orders of magnitude larger than the cosmological signal constitutes a critical challenge. In this work, we

  •   Authors: Khanh-Hung Tran,  Fred-Maurice Ngole-Mboula, J-L. Starck Journal: SIAM Journal on Imaging Sciences Year: 2020 DOI: 10.1137/19M1285469 Download: arXiv Abstract Supervised Dictionary Learning has gained much interest in the recent decade and has shown significant performance improvements in image classification. However, in general, supervised learning needs a large number of labelled samples per class

  •   Authors: Florent Sureau, Alexis Lechat, J-L. Starck Journal: Astronomy and Astrophysics Year: 2020 DOI: 10.1051/0004-6361/201937039 Download: ADS | arXiv Abstract The deconvolution of large survey images with millions of galaxies requires developing a new generation of methods that can take a space-variant point spread function into account. These methods have also to be accurate and

  • Hybrid Pk

    Hybrid Pℓ(k): general, unified, non-linear matter power spectrum in redshift space  Authors: Bose, Benjamin;Winther, Hans A.;Pourtsidou, Alkistis;Casas, Santiago;Lombriser, Lucas;Xia, Qianli;Cataneo, Matteo Journal: Journal of Cosmology and Astroparticle Physics, Issue 09, article id. 001 (2020) Year: 09/2020 Download: Inspire| Arxiv | DOI Hybrid Pl(k): general, unified, non-linear matter power spectrum in redshift space Abstract Constraints on

  • Distance duality relation

    Euclid: impact of nonlinear prescriptions on cosmological parameter estimation from weak lensing cosmic shear   Authors: Martinelli, M.;Martins, C. J. A. P.;Nesseris, S.;Sapone, D.;Tutusaus, I.;Avgoustidis, A.;Camera, S.;Carbone, C.;Casas, S.;Ilić, S.;Sakr, Z.;Yankelevich, V.;et al. Journal:     Year: 07/2020 Download: Inspire| Arxiv Abstract In metric theories of gravity with photon number conservation, the luminosity and angular

  •   Authors: S. Farrens, A. Grigis, L. El Gueddari, Z. Ramzi, Chaithya G. R., S. Starck, B. Sarthou, H. Cherkaoui, P.Ciuciu, J-L. Starck Journal: Astronomy and Computing Year: 2020 DOI: 10.1016/j.ascom.2020.100402 Download: ADS | arXiv Abstract We present the open-source image processing software package PySAP (Python Sparse data Analysis Package) developed for the COmpressed Sensing for

  • XC importance

    Euclid: impact of nonlinear prescriptions on cosmological parameter estimation from weak lensing cosmic shear   Authors: Tutusaus, I.;Martinelli, M.;Cardone, V. F.;Camera, S.;Yahia-Cherif, S.;Casas, S.;Blanchard, A.;Kilbinger, M.;Lacasa, F.;Sakr, Z.;Ilić, S.;Kunz, M.;Carbone, C.;Castander, F. J.;Dournac, F.;Fosalba, P.;Kitching, T.;Markovic, K.;Mangilli, A.;Pettorino, V.;Sapone, D.;Yankelevich, V.;et al. Journal:   Astronomy & Astrophysics, Volume 643, id.A70, 17 pp. Year: 11/2020 Download:

  • Euclid: The reduced shear approximation and magnification bias for Stage IV cosmic shear experiments Authors: A.C. Deshpande, …, S. Casas, M. Kilbinger, V. Pettorino, S. Pires, J.-L. Starck, F. Sureau, et al. Journal: Astronomy and Astrophysics Year: 2020 DOI:  10.1051/0004-6361/201937323 Download: ADS | arXiv   Abstract Stage IV weak lensing experiments will offer more than an

  • Euclid: The selection of quiescent and star-forming galaxies using observed colours Authors: L. Bisigello, …, V. Pettorino, S. Pires, F. Sureau, et al. Journal: MNRAS Year: 2020 DOI:  10.1093/mnras/staa885 Download: ADS | arXiv   Abstract The Euclid mission will observe well over a billion galaxies out to z∼6 and beyond. This will offer an unrivalled opportunity to investigate

  • Euclid preparation: VI. Verifying the Performance of Cosmic Shear Experiments Authors: Euclid Collaboration, P. Paykari, …, S. Farrens, M. Kilbinger, V. Pettorino, S. Pires, J.-L. Starck, F. Sureau, et al. Journal: Astronomy and Astrophysics Year: 2020 DOI:  10.1051/0004-6361/201936980 Download: ADS | arXiv   Abstract Our aim is to quantify the impact of systematic effects on the

  • Deep learning is starting to offer promising results for reconstruction in Magnetic Resonance Imaging (MRI). A lot of networks are being developed, but the comparisons remain hard because the frameworks used are not the same among studies, the networks are not properly re-trained, and the datasets used are not the same among comparisons. The recent

  • Constraining neutrino masses with weak-lensing multiscale peak counts Massive neutrinos influence the background evolution of the Universe as well as the growth of structure. Being able to model this effect and constrain the sum of their masses is one of the key challenges in modern cosmology. Weak-lensing cosmological constraints will also soon reach higher levels

  • The notion of self acceleration has been introduced as a convenient way to theoretically distinguish cosmological models in which acceleration is due to modified gravity from those in which it is due to the properties of matter or fields. In this paper we review the concept of self acceleration as given, for example, by [1],

  • DeepMass: The first Deep Learning reconstruction of dark matter maps from weak lensing observational data (DES SV weak lensing data)DeepMass This is the first reconstruction of dark matter maps from weak lensing observational data using deep learning. We train a convolution neural network (CNN) with a Unet based architecture on over 3.6 x 10^5 simulated data

  • Fitting formula

    Emulators for the nonlinear matter power spectrum beyond ΛCDM  Authors: Winther, Hans A.; Casas, Santiago; Baldi, Marco; Koyama, Kazuya; Li, Baojiu; Lombriser, Lucas; Zhao, Gong-Bo  Journal: Physical Review D, Volume 100, Issue 12, article id.123540 Year: 12/2019 Download: Inspire| Arxiv Abstract Accurate predictions for the nonlinear matter power spectrum are needed to confront theory with

  • Euclid preparation: V. Predicted yield of redshift 7 Authors: Euclid Collaboration, R. Barnett, …, S. Farrens, M. Kilbinger, V. Pettorino, F. Sureau, et al. Journal: Astronomy and Astrophysics Year: 2019 DOI:  10.1051/0004-6361/201936427 Download: ADS | arXiv   Abstract We provide predictions of the yield of 7<z<9 quasars from the Euclid wide survey, updating the calculation presented

  •   Authors: F. NAMMOUR, M. A. SCHMITZ, F. M. NGOLÈ MBOULA, J.-L. STARCK, J. N. GIRARD Journal: Proceedings of SPIE Year: 2019 Download: DOI     Abstract Weak gravitational lensing is a very promising probe for cosmology that relies on highly precise shape measurements. Several new instruments are being deployed and will allow for weak

  • Space test of the Equivalence Principle: first results of the MICROSCOPE mission Authors: P. Touboul, G. Metris, M. Rodrigues, Y. André, Q. Baghi, J. Bergé, D. Boulanger, S. Bremer, R. Chhun, B. Christophe, V. Cipolla, T. Damour, P. Danto, H. Dittus, P. Fayet, B. Foulon, P.-Y. Guidotti, E. Hardy, P.-A. Huynh, C. Lämmerzahl, V. Lebat,

  •   Authors: F. NAMMOUR, M. A. SCHMITZ, F. M. NGOLÈ MBOULA, J.-L. STARCK, J. N. GIRARD Journal: Proceedings of SPIE Year: 2019 Download: DOI     Abstract Weak gravitational lensing is a very promising probe for cosmology that relies on highly precise shape measurements. Several new instruments are being deployed and will allow for weak

  • The impact of baryonic physics and massive neutrinos on weak lensing peak statistics  Authors: M. Fong, M. Choi, V. Catlett, B. Lee, A. Peel, R. Bowyer,  L. J. King, I. G. McCarthy Journal: MNRAS Year: 2019 Download: ADS | arXiv Abstract We study the impact of baryonic processes and massive neutrinos on weak lensing peak statistics

  •   Authors: M.A. Schmitz, J.-L. Starck, F. Ngole Mboula, N. Auricchio, J. Brinchmann, R.I. Vito Capobianco, R. Clédassou, L. Conversi, L. Corcione, N. Fourmanoit, M. Frailis, B. Garilli, F. Hormuth, D. Hu, H. Israel, S. Kermiche, T. D. Kitching, B. Kubik, M. Kunz, S. Ligori, P.B. Lilje, I. Lloro, O. Mansutti, O. Marggraf, R.J. Massey,

  •   Authors: Euclid Collaboration, R. Adam, …, S. Farrens, et al. Journal: A&A Year: 2019 DOI: 10.1051/0004-6361/201935088 Download: ADS | arXiv Abstract 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

  • logfsigma8

    Measuring Gravity at Cosmological Scales  Authors:  Luca Amendola , Dario Bettoni, Ana Marta Pinho,  Santiago Casas, Journal: Review Paper Year: 02/2019 Download: Inspire| Arxiv Abstract This paper is a pedagogical introduction to models of gravity and how to constrain them through cosmological observations. We focus on the Horndeski scalar-tensor theory and on the quantities that

  •   Authors: Lorenzo Pizzuti (Trieste U.), Ippocratis D. Saltas (Prague, Inst. Phys.), Santiago Casas (AIM, Saclay),Luca Amendola (U. Heidelberg, ITP), Andrea Biviano (Trieste Observ.) Journal: Submitted to MNRAS Year: 01/2019 Download: Inspire| Arxiv Abstract The gravitational slip parameter is an important discriminator between large classes of gravity theories at cosmological and astrophysical scales. In this work

  •   Authors: M.O. Irfan, J.Bobin, M-A.Miville-Deschenes, I.Grenier  Journal: A&A Year: 2018 Download: ADS | arXiv Abstract Context: The Planck data releases have provided the community with sub-millimetre and radio observations of the full-sky at unprecedented resolutions. We make use of the Planck 353, 545 and 857 GHz maps alongside the IRAS 3000 GHz map. These maps

  •   Authors: C. Kervazo, J. Bobin, C. Chenot Journal: Signal Processing Year: 2018 Download: Paper Abstract Blind Source Separation (BSS) is one of the major tools to analyze multispectral data with applications that range from astronomical to biomedical signal processing. Nevertheless, most BSS methods fail when the number of sources becomes large, typically exceeding a

  •   Authors: A. Panousopoulou, S. Farrens, K. Fotiadou, A. Woiselle, G. Tsagkatakis, J-L. Starck,  P. Tsakalides Journal: arXiv Year: 2018 Download: ADS | arXiv Abstract Current trends in scientific imaging are challenged by the emerging need of integrating sophisticated machine learning with Big Data analytics platforms. This work proposes an in-memory distributed learning architecture for enabling sophisticated learning and optimization techniques on

  •   Authors: Santiago Casas, Georgios K. Karananas (Munich U., ASC), Martin Pauly (U. Heidelberg, ITP), Javier Rubio (U. Heidelberg, ITP & Helsinki Inst. of Phys.) Journal: Submitted to JCAP Year: 11/2018 Download: Inspire| Arxiv Scale-invariant alternatives to general relativity. The inflation–dark-energy connection Abstract We discuss the cosmological phenomenology of biscalar–tensor models displaying a maximally symmetric

  • Distinguishing standard and modified gravity cosmologies with machine learning  Authors: A. Peel, F. Lalande, J.-L. Starck, V. Pettorino, J. Merten,  C. Giocoli, M. Meneghetti,  M. Baldi Journal: PRD Year: 2019 Download: ADS | arXiv Abstract We present a convolutional neural network to classify distinct cosmological scenarios based on the statistically similar weak-lensing maps they generate. Modified

  • On the dissection of degenerate cosmologies with machine learning  Authors: J. Merten,  C. Giocoli, M. Baldi, M. Meneghetti, A. Peel, F. Lalande, J.-L. Starck, V. Pettorino Journal: MNRAS Year: 2019 Download: ADS | arXiv Abstract Based on the DUSTGRAIN-pathfinder suite of simulations, we investigate observational degeneracies between nine models of modified gravity and massive neutrinos. Three

  •   Authors: M. Crisostomi , K. Koyama, D. Langlois, K. Noui and D. A. Steer Journal:   Year: 2018 Download: arXiv Abstract In the context of Degenerate Higher-Order Scalar-Tensor (DHOST) theories, we study cosmological solutions and their stability properties. In particular, we explicitly illustrate the crucial role of degeneracy by showing how the higher order homogeneous

  •   Authors: Noemi Frusciante (U. Lisbon (main)), Simone Peirone (Leiden U.), Santiago Casas (CEA Paris-Saclay), Nelson A. Lima (U. Heidelberg, ITP) Journal: Submitted to PRD Year: 10/2018 Download: Inspire| Arxiv Abstract In the context of the effective field theory of dark energy (EFT) we perform agnostic explorations of Horndeski gravity. We choose two parametrizations for

  •   Authors: C. Kervazo, J. Bobin, C. Chenot Journal: Signal Processing Year: 2018 Download: Paper Abstract Blind Source Separation (BSS) is one of the major tools to analyze multispectral data with applications that range from astronomical to biomedical signal processing. Nevertheless, most BSS methods fail when the number of sources becomes large, typically exceeding a

  •   Authors: A. I. Salvador, F. J. Sánchez, A. Pagul et al. Journal:   Year: 07/2018 Download: ADS| Arxiv Abstract Non-linear bias measurements require a great level of control of potential systematic effects in galaxy redshift surveys. Our goal is to demonstrate the viability of using Counts-in-Cells (CiC), a statistical measure of the galaxy distribution,

  •   Authors: M.E. Jones, A.C. Taylor, M. Aich et al. Journal: MNRAS Year: 2018 Download: ADS | arXiv Abstract The C-Band All-Sky Survey (C-BASS) is an all-sky full-polarization survey at a frequency of 5 GHz, designed to provide complementary data to the all-sky surveys of WMAP and Planck, and future CMB B-mode polarization imaging surveys. The

  •   Authors: M. Kilbinger Journal:   Year: 07/2018 Download: ADS| Arxiv Abstract In this manuscript of the habilitation à diriger des recherches (HDR), the author presents some of his work over the last ten years. The main topic of this thesis is cosmic shear, the distortion of images of distant galaxies due to weak gravitational

  •   Authors: A. Pujol, M. Kilbinger, F. Sureau & J. Bobin Journal:   Year: 06/2018 Download: ADS| Arxiv Abstract We present a new method to estimate shear measurement bias in image simulations that significantly improves its precision with respect to the state-of-the-art methods. This method is based on measuring the shear response for individual images.

  • Breaking degeneracies in modified gravity with higher (than 2nd) order weak-lensing statistics  Authors: A. Peel, V. Pettorino, C. Giocoli, J.-L. Starck, M. Baldi Journal: A&A Year: 2018 Download: ADS | arXiv Abstract General relativity (GR) has been well tested up to solar system scales, but it is much less certain that standard gravity remains an accurate description on the

  •   Authors: Ana Marta Pinho,  Santiago Casas, Luca Amendola Journal: Accepted for JCAP Year: 05/2018 Download: Inspire| Arxiv Abstract In this work, we use recent data on the Hubble expansion rate H(z), the quantity fσ8(z) from redshift space distortions and the statistic Eg from clustering and lensing observables to constrain in a model-independent way the

  •   Authors: A. Spurio Mancini, R. Reischke, V. Pettorino, B.M. Scháefer, M. Zumalacárregui Journal: Submitted to MNRAS Year: 2018 Download: ADS | arXiv Abstract Cosmic shear, the weak gravitational lensing caused by the large-scale structure, is one of the primary probes to test gravity with current and future surveys. There are two main techniques to analyse a cosmic shear survey;

  •   Authors: N. Jeffrey, F. B. Abdalla, O. Lahav, F. Lanusse, J.-L. Starck, et al Journal:   Year: 01/2018 Download: ADS| Arxiv Abstract Mapping the underlying density field, including non-visible dark matter, using weak gravitational lensing measurements is now a standard tool in cosmology. Due to its importance to the science results of current and upcoming surveys, the quality

  •   Authors: DES Collaboration Journal:   Year: 01/2018 Download: ADS| Arxiv Abstract We describe the first public data release of the Dark Energy Survey, DES DR1, consisting of reduced single epoch images, coadded images, coadded source catalogs, and associated products and services assembled over the first three years of DES science operations. DES DR1 is

  •   Authors: M.A. Schmitz, M. Heitz, N. Bonneel, F.-M. Ngolè, D. Coeurjolly, M. Cuturi, G. Peyré & J.-L. Starck Journal: SIAM SIIMS Year: 2018 Download: ADS | arXiv   Abstract This article introduces a new non-linear dictionary learning method for histograms in the probability simplex. The method leverages optimal transport theory, in the sense that

  •   Authors: A. Knebe, F. R. Pearce, V. Gonzalez-Perez et al. Journal:   Year: 12/2017 Download: ADS| Arxiv Abstract We present a comparison of nine galaxy formation models, eight semi-analytical and one halo occupation distribution model, run on the same underlying cold dark matter simulation (cosmological box of co-moving width 125h−1 Mpc, with a dark-matter

  •   Authors: Marco Crisostomi and Kazuya Koyama Journal: PRD Year: 2018 Download: arXiv Abstract The recent simultaneous detection of gravitational waves and a gamma ray burst from a neutron star merger significantly shrank the space of viable scalar-tensor theories by demanding that the speed of gravity is equal to that of light. The survived theories

  •   Authors: M.O. Irfan, J.Bobin  Journal: MNRAS Year: 2017 Download: ADS | arXiv Abstract Component separation for the Planck HFI data is primarily concerned with the estimation of thermal dust emission, which requires the separation of thermal dust from the cosmic infrared background (CIB). For that purpose, current estimation methods rely on filtering techniques to decouple

  •   Authors: Marco Crisostomi and Kazuya Koyama Journal: PRD Year: 2018 Download: arXiv Abstract The almost simultaneous detection of gravitational waves and a short gamma-ray burst from a neutron star merger has put a tight constraint on the difference between the speed of gravity and light. In the four-dimensional scalar-tensor theory with second order equations

  •   Authors: DES Collaboration Journal:   Year: 08/2017 Download: ADS| Arxiv Abstract We present cosmological results from a combined analysis of galaxy clustering and weak gravitational lensing, using 1321 deg$^2$ of $griz$ imaging data from the first year of the Dark Energy Survey (DES Y1). We combine three two-point functions: (i) the cosmic shear correlation

  •   Authors: C. Chang, A. Pujol, B. Mawdsley et al. Journal:   Year: 08/2017 Download: ADS| Arxiv Abstract We construct the largest curved-sky galaxy weak lensing mass map to date from the DES first-year (DES Y1) data. The map, about 10 times larger than previous work, is constructed over a contiguous $\approx1,500 $deg$^2$, covering a comoving

  • Sparse reconstruction of the merging A520 cluster system  Authors: A. Peel, F. Lanusse, J.-L. Starck Journal: ApJ Year: 08/2017 Download: ADS| Arxiv Abstract Merging galaxy clusters present a unique opportunity to study the properties of dark matter in an astrophysical context. These are rare and extreme cosmic events in which the bulk of the baryonic

  •   Authors: A. Pujol, F. Sureau, J. Bobin et al. Journal: A&A Year: 06/2017 Download: ADS| Arxiv Abstract We present a study of the dependencies of shear and ellipticity bias on simulation (input) and measured (output) parameters, noise, PSF anisotropy, pixel size and the model bias coming from two different and independent shape estimators. We use

  •   Authors: Frontera-Pons, J., Sureau, F., Bobin, J. and Le Floc’h E. Journal: Astronomy & Astrophysics Year: 2017 Download: ADS | arXiv Abstract With the increasing number of deep multi-wavelength galaxy surveys, the spectral energy distribution (SED) of galaxies has become an invaluable tool for studying the formation of their structures and their evolution. In this

  • Authors: C. Lin, M. Kilbinger Journal: Submitted to A&A letters Year: 2017 Download: ADS | arXiv   Abstract Weak-lensing (WL) peak counts provide a straightforward way to constrain cosmology, and results have been shown promising. However, the importance of understanding and dealing with systematics increases as data quality reaches an unprecedented level. One of the sources

  •   Authors: F. Ngolè Mboula, J-L. Starck Journal: arXiv Year: 2017 Download: ADS | arXiv   Abstract Context: in astronomy, observing large fractions of the sky within a reasonable amount of time implies using large field-of-view (fov) optical instruments that typically have a spatially varying Point Spread Function (PSF). Depending on the scientific goals, galaxies images

  •   Authors: M. Jiang, J. Bobin, J-L. Starck Journal: SIAM J. Imaging Sci. Year: 2017 Download: ADS | arXiv | SIIMS   Abstract Blind Source Separation (BSS) is a challenging matrix factorization problem that plays a central role in multichannel imaging science. In a large number of applications, such as astrophysics, current unmixing methods are limited since

  •   Authors: S. Farrens, J-L. Starck, F. Ngolè Mboula Journal: A&A Year: 2017 Download: ADS | arXiv Abstract Removing the aberrations introduced by the Point Spread Function (PSF) is a fundamental aspect of astronomical image processing. The presence of noise in observed images makes deconvolution a nontrivial task that necessitates the use of regularisation. This task

  •   Authors: S. Casas, M. Kunz, M. Martinelli, V. Pettorino Journal: Physics Letters B Year: 2017 Download: ADS | arXiv Abstract Modified Gravity theories generally affect the Poisson equation and the gravitational slip (effective anisotropic stress) in an observable way, that can be parameterized by two generic functions (η and μ) of time and space. We

  • Authors: M. Kilbinger, C. Heymans, M. Asgari et al. Journal: MNRAS Year: 2017 Download: ADS | arXiv Abstract We compute the spherical-sky weak-lensing power spectrum of the shear and convergence. We discuss various approximations, such as flat-sky, and first- and second- order Limber equations for the projection. We find that the impact of adopting these approximations

  •   Authors: A. Pujol, R. A. Skibba, E. Gaztañaga et al. Journal: MNRAS Year: 02/2017 Download: ADS| Arxiv Abstract We present a clustering comparison of 12 galaxy formation models (including Semi-Analytic Models (SAMs) and Halo Occupation Distribution (HOD) models) all run on halo catalogues and merger trees extracted from a single {\Lambda}CDM N-body simulation. We compare

  •   Authors: A. Pujol, K. Hoffmann, N. Jiménez et al. Journal: A&A Year: 02/2017 Download: ADS| Arxiv Abstract Using a dark matter simulation we show how halo bias is determined by local density and not by halo mass. This is not totally surprising as, according to the peak-background split model, local matter density (bar δ) is

  • Cosmological constraints with weak-lensing peak counts and second-order statistics in a large-field survey  Authors: A. Peel, C.-A. Lin, F. Lanusse, A. Leonard, J.-L. Starck, M. Kilbinger Journal: A&A Year: 2017 Download: ADS | arXiv   Abstract Peak statistics in weak-lensing maps access the non-Gaussian information contained in the large-scale distribution of matter in the Universe. They

  • Authors: S. Pires, B. Joël, Q. Baghi, P. Touboul, G. Metris Journal: Physical Review D Year: 2016 Download: ADS | arXiv Abstract The MICROSCOPE space mission, launched on April 25, 2016, aims to test the weak equivalence principle (WEP) with a 10-15 precision. Reaching this performance requires an accurate and robust data analysis method, especially since

  • Authors: F. Lanusse, J.-L. Starck, A. Leonard, S. Pires Journal: A&A Year: 2016 Download: ADS | arXiv Abstract Aims: We propose a new mass mapping algorithm, specifically designed to recover small-scale information from a combination of gravitational shear and flexion. Including flexion allows us to supplement the shear on small scales in order to increase the sensitivity

  •   Authors: DESI collaboration Journal: ArXiv Year: 2016 Download: ADS | arXiv   Abstract DESI (Dark Energy Spectroscopic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. To trace the underlying dark matter

  •   Authors: DESI collaboration Journal: ArXiv Year: 2016 Download: ADS | arXiv   Abstract DESI (Dark Energy Spectropic Instrument) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar redshift survey. The DESI instrument is a robotically-actuated, fiber-fed

  • Authors: M. Pierre et al. Journal: MNRAS Year: 2017 Download: ADS | arXiv   Abstract The XXL survey currently covers two 25 sq. deg. patches with XMM observations of ~10ks. We summarise the scientific results associated with the first release of the XXL data set, that occurred mid 2016. We review several arguments for increasing the

  •   Authors: A. Pujol, C. Chang, E. Gaztañaga et al. Journal: MNRAS Year: 10/2016 Download: ADS| Arxiv Abstract We present a new method to measure redshift-dependent galaxy bias by combining information from the galaxy density field and the weak lensing field. This method is based on the work of Amara et al., who use the galaxy

  •   Authors: C.Chenot, J.Bobin Journal: Signal Processing, Elsevier Year: 2016 Download: Elsevier / Preprint     Abstract   Blind Source Separation (BSS) plays a key role to analyze multichannel data since it aims at recovering unknown underlying elementary sources from observed linear mixtures in an unsupervised way. In a large number of applications, multichannel measurements contain corrupted

  • Authors: C. Lin, M. Kilbinger, S. Pires Journal: A&A Year: 2016 Download: ADS | arXiv Abstract This is the third in a series of papers that develop a new and flexible model to predict weak-lensing (WL) peak counts, which have been shown to be a very valuable non-Gaussian probe of cosmology. In this paper, we compare

  •   Authors: F. Ngolè Mboula, J-L. Starck, K. Okumura, J. Amiaux, P. Hudelot Journal: IOP Inverse Problems Year: 2016 Download: ADS | arXiv   Abstract Context: in large-scale spatial surveys, the Point Spread Function (PSF) varies across the instrument field of view (FOV). Local measurements of the PSFs are given by the isolated stars images. Yet,

  •   Authors: H. T. Diehl, E. Neilsen, R. Gruendl et al. Journal: Proceedings of the SPIE Year: 07/2016 Download: ADS Abstract The Dark Energy Survey (DES) is an operating optical survey aimed at understanding the accelerating expansion of the universe using four complementary methods: weak gravitational lensing, galaxy cluster counts, baryon acoustic oscillations, and Type Ia

  •   Authors: C. Chang, A. Pujol, E. Gaztañaga et al. Journal: MNRAS Year: 07/2016 Download: ADS| Arxiv Abstract We measure the redshift evolution of galaxy bias for a magnitude-limited galaxy sample by combining the galaxy density maps and weak lensing shear maps for a ˜116 deg2 area of the Dark Energy Survey (DES) Science Verification (SV)

  • Authors: V. Scottez, Y. Mellier, B. Granett, T. Moutard, M. Kilbinger et al. Journal: MNRAS Year: 2016 Download: ADS | arXiv   Abstract We explore the accuracy of the clustering-based redshift estimation proposed by Ménard et al. when applied to VIMOS Public Extragalactic Redshift Survey (VIPERS) and Canada-France-Hawaii Telescope Legacy Survey (CFHTLS) real data. This method

  •   Authors: K. E. Themelis, A. A. Rontogiannis, K. D. Koutroumbas Journal: IEEE Transactions on Signal Processing Year: 2016 Download: ieeexplore     Abstract In this paper, we study the problem of time-adaptive group sparse signal estimation from a Bayesian viewpoint. We propose two online variational Bayes schemes that are specifically designed to estimate and

  •   Authors: P. V. Giampouras, K. E. Themelis, A. A. Rontogiannis, K. D. Koutroumbas Journal: IEEE Transactions on Geoscience and Remote Sensing Year: 2016 Download: ieeexplore     Abstract In a plethora of applications dealing with inverse problems, e.g., image processing, social networks, compressive sensing, and biological data processing, the signal of interest is known

  • First round of papers published The XXL Survey is a deep X-ray survey observed with the XMM satellite, covering two fields of 25 deg2 each. Observations in many other wavelength, from radio to IR and optical, in both imaging and spectroscopy, complement the survey. The main science case is cosmology with X-ray selected galaxy clusters,

  •   Authors: P. Paykari, S. Pires, J.-L. Starck, A.H. Jaffe Journal: Astronomy & Astrophysics Year: 2015 Download: ADS | arXiv Abstract Weak gravitational lensing provides a unique way of mapping directly the dark matter in the Universe. The majority of lensing analyses use the two-point statistics of the cosmic shear field to constrain the cosmological model, a method

  • Authors: B. Joël, S. Pires, Q. Baghi, P. Touboul, G. Metris Journal: Physical Review D Year: 2015 Download: ADS | arXiv Abstract Missing data are a common problem in experimental and observational physics. They can be caused by various sources, either an instrument’s saturation, or a contamination from an external event, or a data loss. In

  •   Authors:  J. Bobin, F. Sureau and J. -L. Starck Journal: A&A Year: 2015 Download: ADS | arXiv Abstract In this article, we describe a new estimate of the Cosmic Microwave Background (CMB) intensity map reconstructed by a joint analysis of the full Planck 2015 data (PR2) and WMAP nine-years. It provides more than a mere

  • Authors: C. Lin, M. Kilbinger Journal: A&A Year: 2015 Download: ADS | arXiv Abstract Peak counts have been shown to be an excellent tool to extract the non-Gaussian part of the weak lensing signal. Recently, we developped a fast stochastic forward model to predict weak-lensing peak counts. Our model is able to reconstruct the underlying distribution

  •   Authors: A. Knebe, F. R. Pearce, P. A. Thomas et al. Journal: MNRAS  Year: 08/2015 Download: ADS|Arxiv Abstract We present a comparison of 14 galaxy formation models: 12 different semi-analytical models and 2 halo occupation distribution models for galaxy formation based upon the same cosmological simulation and merger tree information derived from it. The participating

  • Authors: T. Schrabback et al. Journal: MNRAS Year: 2015 Download: ADS | arXiv Abstract We present weak lensing constraints on the ellipticity of galaxy-scale matter haloes and the galaxy-halo misalignment. Using data from the Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS), we measure the weighted-average ratio of the aligned projected ellipticity components of galaxy matter haloes and their

  •   Authors: C.Chenot, J.Bobin and J. Rapin Journal: IEEE SPL  Year: Nov. 2015 Download: IEEE Arxiv Abstract Blind source separation is a widely used technique to analyze multichannel data. In many real-world applications, its results can be significantly hampered by the presence of unknown outliers. In this paper, a novel algorithm coined rGMCA (robust Generalized Morphological

  • Authors: P. Simon, … , M. Kilbinger,  et al. Journal: MNRAS Year: 2015 Download: ADS | arXiv Abstract We study the correlations of the shear signal between triplets of sources in the Canada-France-Hawaii Lensing Survey (CFHTLenS) to probe cosmological parameters via the matter bispectrum. In contrast to previous studies, we adopted a non-Gaussian model of the data

  • Authors: C. Lin, M. Kilbinger Journal: A&A Year: 2015 Download: ADS | arXiv Abstract Weak-lensing peak counts has been shown to be a powerful tool for cosmology. It provides non-Gaussian information of large scale structures, complementary to second order statistics. We propose a new flexible method to predict weak lensing peak counts, which can be adapted

  •   Authors: H. Garsden, J. N. Girard, J. L. Starck Journal: A&A Year: 2015 Download: ADS | arXiv   Abstract Context. The LOw Frequency ARray (LOFAR) radio telescope is a giant digital phased array interferometer with multiple antennas distributed in Europe. It provides discrete sets of Fourier components of the sky brightness. Recovering the original brightness

  •   Authors: F. Ngolè Mboula, J-L. Starck, S. Ronayette, K. Okumura, J. Amiaux Journal: A&A Year: 2015 Download: ADS | arXiv   Abstract In large-scale spatial surveys, such as the forthcoming ESA Euclid mission, images may be undersampled due to the optical sensors sizes. Therefore, one may consider using a super-resolution (SR) method to recover aliased

  • Authors: J. Coupon et al. Journal: MNRAS Year: 2015 Download: ADS | arXiv Abstract We present new constraints on the relationship between galaxies and their host dark matter halos, measured from the location of the peak of the stellar-to-halo mass ratio (SHMR), up to the most massive galaxy clusters at redshift z∼0.8z\sim0.8 and over a volume

  •   Authors: M.O. Irfan, C. Dickinson, R.D. Davies, et al.     Journal: MNRAS Year: 2015 Download: ADS | arXiv Abstract We present an analysis of the diffuse emission at 5 GHz in the first quadrant of the Galactic plane using two months of preliminary intensity data taken with the C-Band All Sky Survey (C-BASS) northern

  • Authors: C.-A. Lin, M. Kilbinger. Journal: A&A 576, A24 Year: 2015 Download: ADS | arXiv   Abstract Weak-lensing peak counts has been shown to be a powerful tool for cosmology. It provides non-Gaussian information of large scale structures, complementary to second order statistics. We propose a new flexible method to predict weak lensing peak counts, which

  •   Authors: A. Möller, V. Ruhlmann-Kleider, F. Lanusse, J. Neveu, N. Palanque-Delabrouille, J.-L. Starck Journal: JCAP Year: 2015 Download: ADS | arXiv Abstract Detection of supernovae and, more generally, of transient events in large surveys can provide numerous false detections.In the case of a deferred processing of survey images, this implies reconstructing complete light curves for

  • Effect of inhomogeneities on high precision measurements of cosmological distances  Authors: A. Peel, M. A. Troxel, M. Ishak Journal: PRD Year: 2014 Download: ADS | arXiv Abstract We study effects of inhomogeneities on distance measures in an exact relativistic Swiss-cheese model of the Universe, focusing on the distance modulus. The model has Λ CDM background dynamics,

  •   Authors: R. Joseph, F. Courbin, R. B. Metcalf, …., S.Pires, et al. Journal: A&A Year: 2014 Download: ADS | arXiv Abstract We present an algorithm using principal component analysis (PCA) to subtract galaxies from imaging data and also two algorithms to find strong, galaxy-scale gravitational lenses in the resulting residual image. The combined method is optimised

  •   Authors:  F. Lanusse, P. Paykari, J. -L. Starck et al. Journal: A&A Year: 2014 Download: ADS | arXiv Abstract Aims. The primordial power spectrum describes the initial perturbations that seeded the large-scale structure we observe today. It provides an indirect probe of inflation or other structure-formation mechanisms. In this letter, we recover the primordial power

  •   Authors: S. Pires, S. Mathur, R. A. Garcia, J. Ballot, D. Stello, K. Sato Journal: Astronomy & Astrophysics Year: 2014 Download: ADS | arXiv Abstract In asteroseismology, the observed time series often suffers from incomplete time coverage due to gaps. The presence of periodic gaps may generate spurious peaks in the power spectrum that limit

  •   Authors: Pettorino, V., Amendola, L. Journal: Physics Letters B Year: 2015 Download: ADS | arXiv Abstract Modified gravity theories predict in general a non standard equation for the propagation of gravitational waves. Here we discuss the impact of modified friction and speed of tensor modes on cosmic microwave polarization B modes. We show that the non

  •   Authors: H. T. Diehl, T. M. C. Abbott, J. Annis et al. Journal: Proceedings of the SPIE Year: 08/2014 Download: ADS Abstract The Dark Energy Survey (DES) is a next generation optical survey aimed at understanding the accelerating expansion of the universe using four complementary methods: weak gravitational lensing, galaxy cluster counts, baryon acoustic

  •   Authors: A. Pujol and E. Gaztañaga Journal: MNRAS  Year: 08/2014 Download: ADS|Arxiv Abstract We study how well we can reconstruct the two-point clustering of galaxies on linear scales, as a function of mass and luminosity, using the halo occupation distribution (HOD) in several semi-analytical models (SAMs) of galaxy formation from the Millennium Simulation. We

  • Authors: T. D. Kitching, … , M. Kilbinger, et al. Journal: MNRAS Year: 2014 Download: ADS | arXiv Abstract This paper presents the first application of 3D cosmic shear to a wide-field weak lensing survey. 3D cosmic shear is a technique that analyses weak lensing in three dimensions using a spherical harmonic approach, and does not bin

  •   Authors: J. Rapin, J. Bobin, A. Larue, J.-L. Starck Journal: SIAM Year: 2014 Download: ADS | arXiv Abstract Non-negative blind source separation (BSS) has raised interest in various fields of research, as testified by the wide literature on the topic of non-negative matrix factorization (NMF). In this context, it is fundamental that the sources to be estimated present

  • Authors: L. Fu, M. Kilbinger, T. Erben, C. Heymans,  et al. Journal: MNRAS Year: 2014 Download: ADS | arXiv Abstract Higher-order, non-Gaussian aspects of the large-scale structure carry valuable information on structure formation and cosmology, which is complementary to second-order statistics. In this work we measure second- and third-order weak-lensing aperture-mass moments from CFHTLenS and combine those with CMB anisotropy

  •   Authors: K. E. Themelis, A. A. Rontogiannis, K. D. Koutroumbas Journal: IEEE Transactions on Signal Processing Year: 2014 Download: ieeexplore     Abstract Recently, a number of mostly l1-norm regularized least-squares-type deterministic algorithms have been proposed to address the problem of sparse adaptive signal estimation and system identification. From a Bayesian perspective, this task

  •   Authors: R.A. Garcıa, S. Mathur, S. Pires, et al. Journal: Astronomy & Astrophysics Year: 2014 Download: ADS | arXiv Abstract The NASA Kepler mission has observed more than 190,000 stars in the constellations of Cygnus and Lyra. Around 4 years of almost continuous ultra high-precision photometry have been obtained reaching a duty cycle higher than

  •   Authors:  F. C. Sureau, J. -L. Starck, J. Bobin et al.  Journal: A&A Year: 2014 Download: ADS | arXiv Abstract Missions such as WMAP or Planck measure full-sky fluctuations of the cosmic microwave background and foregrounds, among which bright compact source emissions cover a significant fraction of the sky. To accurately estimate the diffuse components,

  •   Authors:  A. Rassat, J. -L. Starck , P. Paykari et al. Journal: JCAP Year: 2014 Download: ADS | arXiv Abstract Large-scale anomalies have been reported in CMB data with both WMAP and Planck data. These could be due to foreground residuals and or systematic effects, though their confirmation with Planck data suggests they are not due

  • Authors: A. Leonard, F. Lanusse, J.-L. Starck Journal: MNRAS Year: 2014 Download: ADS | arXiv Abstract We present GLIMPSE – Gravitational Lensing Inversion and MaPping with Sparse Estimators – a new algorithm to generate density reconstructions in three dimensions from photometric weak lensing measurements. This is an extension of earlier work in one dimension aimed at applying compressive

  • The effects of structure anisotropy on lensing observables in an exact general relativistic setting for precision cosmology  Authors: M. A. Troxel, M. Ishak, A. Peel Journal: JCAP Year: 2014 Download: ADS | arXiv Abstract The study of relativistic, higher order, and nonlinear effects has become necessary in recent years in the pursuit of precision cosmology. We

  •   Authors: A. Pujol, E. Gaztañaga,  C. Giocoli et al. Journal: MNRAS  Year: 03/2014 Download: ADS|Arxiv Abstract We present a study of the substructure finder dependence of subhalo clustering in the Aquarius Simulation. We run 11 different subhalo finders on the haloes of the Aquarius Simulation and study their differences in the density profile, mass fraction and

  •   Authors: P. Paykari, F. Lanusse, J. -L. Starck et al. Journal: A&A Year: 2014 Download: ADS | arXiv Abstract Aims. The primordial power spectrum describes the initial perturbations in the Universe which eventually grew into the large-scale structure we observe today, and thereby provides an indirect probe of inflation or other structure-formation mechanisms. Here, we

  •   Authors: E. Jullo, S.Pires, M. Jauzac, J.-P. Kneib Journal: MNRAS Year: 2014 Download: ADS | arXiv Abstract In this paper, we compare three methods to reconstruct galaxy cluster density fields with weak lensing data. The first method called FLens integrates an inpainting concept to invert the shear field with possible gaps, and a multi-scale entropy denoising procedure

  •   Authors: J. Bobin,  F. Sureau, J. -L. Starck et al. Journal: A&A Year: 2014 Download: ADS | arXiv Abstract We present a novel estimate of the cosmological microwave background (CMB) map by combining the two latest full-sky microwave surveys: WMAP nine-year and Planck PR1. The joint processing benefits from a recently introduced component separation method

  •   Authors: D. Milioris, G. Tzagkarakis, A. Papakonstantinou, M. Papadopouli, P. Tsakalides Journal: Ad Hoc Networks Year: 2011 Download: Science Direct Abstract Accurate location awareness is of paramount importance in most ubiquitous and pervasive computing applications. Numerous solutions for indoor localization based on IEEE802.11, bluetooth, ultrasonic and vision technologies have been proposed. This paper introduces

  •   Authors: M.O. Irfan, C. Dickinson, R.D. Davies, et al.     Journal: MNRAS Year: 2015 Download: ADS | arXiv     Abstract We present an analysis of the diffuse emission at 5 GHz in the first quadrant of the Galactic plane using two months of preliminary intensity data taken with the C-Band All Sky Survey

  •   Authors: M. Cropper, H. Hoekstra, T. Kitching, …, S. Pires et al. Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract This paper describes the definition of a typical next-generation space-based weak gravitational lensing experiment. We first adopt a set of top-level science requirements from the literature, based on the scale and depth of the galaxy sample,

  •   Authors: R. Massey, H. Hoekstra, T. Kitching, …, S. Pires et al. Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract The first half of this paper explores the origin of systematic biases in the measurement of weak gravitational lensing. Compared to previous work, we expand the investigation of point spread function instability and fold in for

  •   Authors: J. Rapin, J. Bobin, A. Larue, J.-L. Starck Journal: IEEE Year: 2013 Download: ADS | arXiv Abstract Non-negative blind source separation (BSS) has raised interest in various fields of research, as testified by the wide literature on the topic of non-negative matrix factorization (NMF). In this context, it is fundamental that the sources to be estimated present

  •   Authors: D. P. Machado, A. Leonard, J.-L. Starck, F. B. Abdalla, S. Jouvel Journal: A&A Year: 2013 Download: ADS | arXiv Abstract We present the DARTH FADER algorithm, a new wavelet-based method for estimating redshifts of galaxy spectra in spectral surveys that is particularly adept in the very low SNR regime. We use a standard

  •   Authors: A. Rassat, J. -L. Starck and F. -X. Dupe Journal: A&A Year: 2013 Download: ADS | arXiv Abstract Though debated, the existence of claimed large-scale anomalies in the CMB is not totally dismissed. In parallel to the debate over their statistical significance, recent work focussed on masks and secondary anisotropies as potential sources of

  • Authors: J. Benjamin, L. Van Waerbeke, C. Heymans, M. Kilbinger, et al. Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract The Canada-France-Hawaii Telescope Lensing Survey (CFHTLenS) comprises deep multi-colour (u*g’r’i’z’) photometry spanning 154 square degrees, with accurate photometric redshifts and shape measurements. We demonstrate that the redshift probability distribution function summed over galaxies provides an

  •   Authors:  J. Bobin, F. Sureau , P. Paykari et al. Journal: A&A Year: 2013 Download: ADS | arXiv Abstract Recovering the cosmic microwave background (CMB) from WMAP data requires that Galactic foreground emissions are accurately separated out. Most component separation techniques rely on second-order statistics such as internal linear combination (ILC) techniques. We present a

  •   Authors:  A. Rassat and J. -L. Starck  Journal: A&A Year: 2013 Download: ADS | arXiv Abstract There is currently a debate over the existence of claimed statistical anomalies in the cosmic microwave background (CMB), recently confirmed in Planck data. Recent work has focussed on methods for measuring statistical significance, on masks and on secondary anisotropies

  • Authors: C. Heymans, E. Grocutt, A. Heavens, M. Kilbinger, et al. Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract We present a finely-binned tomographic weak lensing analysis of the Canada-France-Hawaii Telescope Lensing Survey, CFHTLenS, mitigating contamination to the signal from the presence of intrinsic galaxy alignments via the simultaneous fit of a cosmological model and an intrinsic alignment model.

  • Authors: F. Simpson, C. Heymans, D. Parkinson, C. Blake, M. Kilbinger, et al. Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract Dark energy may be the first sign of new fundamental physics in the Universe, taking either a physical form or revealing a correction to Einsteinian gravity. Weak gravitational lensing and galaxy peculiar velocities provide complementary probes of

  •   Authors: E. Chapman, F. B. Abdalla, J. Bobin, J.-L. Starck Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract The accurate and precise removal of 21-cm foregrounds from Epoch of Reionization redshifted 21-cm emission data is essential if we are to gain insight into an unexplored cosmological era. We apply a non-parametric technique, Generalized Morphological Component Analysis

  • Authors: M. Kilbinger, et al. Journal: MNRAS Year: 2013 Download: ADS | arXiv Abstract We present cosmological constraints from 2D weak gravitational lensing by the large-scale structure in the Canada-France Hawaii Telescope Lensing Survey (CFHTLenS) which spans 154 square degrees in five optical bands. Using accurate photometric redshifts and measured shapes for 4.2 million galaxies between

  •   Authors: A. Labatie, J.-L. Starck, M. Lachièze-Rey Journal: ApJ Year: 2012 Download: ADS | arXiv Abstract Large-scale structures in the Universe are a powerful tool to test cosmological models and constrain cosmological parameters. A particular feature of interest comes from Baryon Acoustic Oscillations (BAOs), which are sound waves traveling in the hot plasma of the early

  •   Authors: G. Tsagkatakis, A. Woiselle, G. Tzagkarakis, M. Bousquet, J.-L. Starck and P. Tsakalides Journal: SPIE Year: 2012 Download: SPIE Abstract Range Imaging (RI) has sparked an enthusiastic interest recently due to the numerous applications that can benefit from the presence 3D data. One of the most successful techniques for RI employs Time-of-Flight (ToF)

  •   Authors: G. Tzagkarakis, G. Tsagkatakis, J.-L. Starck, P. Tsakalides Journal: EUSIPCO Year: 2012 Download: IEEE Abstract In this paper, we introduce an architecture for addressing the problem of video classification based on a set of compressed features, without the need of accessing the original full-resolution video data. In particular, the video frames are acquired

  •   Authors: K. E. Themelis, F. Schmidt, O. Sykioti, A. A. Rontogiannis, K. D. Koutroumbas, I. A. Daglis Journal: Planetary and Space Science Year: 2012 Download: elsevier     Abstract This paper presents a comparative study of three different types of estimators used for supervised linear unmixing of two MEx/OMEGA hyperspectral cubes. The algorithms take

  •   Authors: J. Bobin, J. -L. Starck, F. Sureau, S. Basak Journal: A&A Year: 2012 Download: ADS | arXiv Abstract The Cosmological Microwave Background (CMB) is of premier importance for the cosmologists to study the birth of our universe. Unfortunately, most CMB experiments such as COBE, WMAP or Planck do not provide a direct measure of

  •   Authors: P. Arnalte-Mur, A. Labatie, N. Clerc, V. J. Martínez, J.-L. Starck, et al. Journal: A&A Year: 2012 Download: ADS | arXiv Abstract Baryon Acoustic Oscillations (BAO) are a feature imprinted in the density field by acoustic waves travelling in the plasma of the early universe. Their fixed scale can be used as a standard

  •   Authors: K. E. Themelis, A. A. Rontogiannis, K. D. Koutroumbas Journal: IEEE Transactions on Signal Processing Year: 2012 Download: ieeexplore     Abstract In this paper the problem of semisupervised hyperspectral unmixing is considered. More specifically, the unmixing process is formulated as a linear regression problem, where the abundance’s physical constraints are taken into

  •   Authors:  P. Paykari, J. -L. Starck and M. J. Fadili Journal: Astronomy and Astrophysics Year: 2012 Download: ADS | arXiv Abstract The cosmic microwave background (CMB) power spectrum is a powerful cosmological probe as it entails almost all the statistical information of the CMB perturbations. Having access to only one sky, the CMB power spectrum

  •   Authors: G. Tzagkarakis, P. Charalampidis, G. Tsagkatakis, J.-L. Starck, P. Tsakalides Journal: PCS Year: 2012 Download: IEEE Abstract In this paper, we address the problem of video classification from a set of compressed features. In particular, the properties of linear random projections in the framework of compressive sensing are exploited to reduce the task

  •   Authors: A. Leonard, S. Pires, J.-L. Starck Journal: MNRAS Year: 2012 Download: ADS | arXiv Abstract The aperture mass statistic is a common tool used in weak lensing studies. By convolving lensing maps with a filter function of a specific scale, chosen to be larger than the scale on which the noise is dominant, the lensing

  •   Authors: J. Coupon, M. Kilbinger, H. J. McCracken, et al. Journal: A&A Year: 2012 Download: ADS | arXiv Abstract We present a detailed investigation of the changing relationship between galaxies and the dark matter haloes they inhabit from z~1.2 to the present day. We do this by comparing precise galaxy clustering measurements over 133 deg2

  •   Authors: F. Lanusse, A. Rassat, J.-L. Starck Journal: A&A Year: 2012 Download: ADS | arXiv Abstract Future cosmological surveys will provide 3D large scale structure maps with large sky coverage, for which a 3D Spherical Fourier-Bessel (SFB) analysis in spherical coordinates is natural. Wavelets are particularly well-suited to the analysis and denoising of cosmological data,

  •   Authors: E. Deriaz, J.-L. Starck, S.Pires Journal: A&A Year: 2012 Download: ADS | arXiv Abstract To derive the convergence field from the gravitational shear (gamma) of the background galaxy images, the classical methods require a convolution of the shear to be performed over the entire sky, usually expressed thanks to the Fast Fourier transform (FFT). However,

  •   Authors: S. Pires, A. Leonard,  J.-L. Starck Journal: MNRAS Year: 2012 Download: ADS | arXiv Abstract Weak gravitational lensing has become a common tool to constrain the cosmological model. The majority of the methods to derive constraints on cosmological parameters use second-order statistics of the cosmic shear. Despite their success, second-order statistics are not optimal and

  • Authors: A. Leonard, F.-X. Dupé, J.-L. Starck Journal: A&A Year: 2012 Download: ADS | arXiv Abstract (Abridged) Weak gravitational lensing is an ideal probe of the dark universe. In recent years, several linear methods have been developed to reconstruct the density distribution in the Universe in three dimensions, making use of photometric redshift information to determine the

  •   Authors: G. Tzagkarakis, A. Woiselle, P. Tsakalides, J.-L. Starck Journal: VISAPP Year: 2012 Download: Sitepress Abstract Lightweight remote imaging systems have been increasingly used in surveillance and reconnaissance. Nevertheless, the limited power, processing and bandwidth resources is a major issue for the existing solutions, not well addressed by the standard video compression techniques. On

  •   Authors: J. Bobin, J. -L. Starck, F. Sureau and J. Fadili Journal: A&A Year: 2012 Download: ADS | arXiv Abstract Estimating the cosmological microwave background is of utmost importance for cosmology. However, its estimation from full-sky surveys such as WMAP or more recently Planck is challenging: CMB maps are generally estimated via the application of

  •   Authors: D. L. Donoho, Y. Tsaig, I. Drori, J.-L. Starck Journal: IEEE Year: 2012 Download: IEEE Abstract Finding the sparsest solution to underdetermined systems of linear equations y = Φx is NP-hard in general. We show here that for systems with “typical”/“random” Φ, a good approximation to the sparsest solution is obtained by applying a fixed number of

  •   Authors: A. Labatie, J.-L. Starck, M. Lachièze-Rey Journal: ApJ Year: 2012 Download: ADS | arXiv Abstract Baryon Acoustic Oscillations are a feature imprinted in the galaxy distribution by acoustic waves traveling in the plasma of the early universe. Their detection at the expected scale in large-scale structures strongly supports current cosmological models with a nearly linear

  •   Authors: D. Milioris, G. Tzagkarakis, P. Jacquet Journal: EUSIPCO Year: 2011 Download: IEEE Abstract Accurate indoor localization is a significant task for many ubiquitous and pervasive computing applications, with numerous solutions based on IEEE802.11, Bluetooth, ultrasound and infrared technologies being proposed. The inherent sparsity present in the problem of location estimation motivates in a natural

  •   Authors: G. Tzagkarakis, J.-L. Starck, P. Tsakalides Journal: EUSIPCO Year: 2011 Download: IEEE Abstract Wireless networks comprised of low-cost sensory devices have been increasingly used in surveillance both at the civilian and military levels. Limited power, processing, and bandwidth resources is a major issue for abandoned sensors, which should be addressed to increase the network’s performance and

  •   Authors: F. -X. Dupe, A. Rassat, J. -L. Starck and M. J. Fadili Journal: A&A Year: 2011 Download: ADS | arXiv Abstract One of the main challenges of modern cosmology is to understand the nature of dark energy. The Integrated Sachs-Wolfe (ISW) effect is sensitive to dark energy and presents an independent signature of dark

  •   Authors: N. Barbey, M. Sauvage, J.-L. Starck, R. Ottensamer, P. Chanial Journal: A&A Year: 2011 Download: ADS | arXiv Abstract The Herschel Space Observatory of ESA was launched in May 2009 and is in operation since. From its distant orbit around L2 it needs to transmit a huge quantity of information through a very limited bandwidth. This is especially

  •   Authors: A. Woiselle, J.-L. Starck, J. Fadili Journal: Journal of Mathematical Imaging and Vision Year: 2010 Download: Springer Abstract In this paper, we first present a new implementation of the 3-D fast curvelet transform, which is nearly 2.5 less redundant than the Curvelab (wrapping-based) implementation as originally proposed in Ying et al. (Proceedings of wavelets

  •   Authors: A. Labatie, J-L. Starck, M. Lachièze-Rey, P. Arnalte-Mur Journal: arXiv Year: 2010 Download: ADS | arXiv Abstract We study the uncertainty in different two-point correlation function (2PCF) estimators in currently available galaxy surveys. This is motivated by the active subject of using the baryon acoustic oscillations (BAOs) feature in the correlation function as a tool

  •   Authors: Y, Moudden, J. Bobin Journal: IEEE Year: 2014 Download: IEEE Abstract Non-negative blind source separation (BSS) has raised interest in various fields of research, as testified by the wide literature on the topic of non-negative matrix factorization (NMF). In this context, it is fundamental that the sources to be estimated present some diversity in order

  •   Authors: C. Chesneau, J. Fadili, J.-L. Starck Journal: Applied and Computational Harmonic Analysis Year: 2010 Download: Project Euclid Abstract In this paper, we propose a fast image deconvolution algorithm that combines adaptive block thresholding and Vaguelet-Wavelet Decomposition. The approach consists in first denoising the observed image using a wavelet-domain Stein block thresholding, and then inverting

  • Fitting formulae of the reduced-shear power spectrum for weak lensing Reference Martin Kilbinger, 2010, arXiv:1004.3493 Description We provide fitting formulae for the reduced-shear power-spectrum correction which is third-order in the lensing potential. This correction reaches up to 10% of the total lensing spectrum. Higher-order correction terms are one order of magnitude below the third-order term.

  •   Authors: A. Woiselle, J.-L. Starck, J. Fadili Journal: Applied and Computational Harmonic Analysis Year: 2010 Download: Science Direct Abstract This paper describes two new 3D curvelet decompositions, which are built in a way similar to the first generation of curvelets (Starck et al., 2002 [35]). The first one, called BeamCurvelet transform, is well designed

  •   Authors: S. Pires, J.-L. Starck, A. Amara, A. Réfrégier, R. Teyssier Journal: Astronomy & Astrophysics Year: 2009 Download: ADS Abstract Weak gravitational lensing provides a unique way of mapping directly the dark matter in the Universe. The majority of lensing analyses use the two-point statistics of the cosmic shear field to constrain the cosmological model,

  • A new cosmic shear function: Optimised E-/B-mode decomposition on a finite interval Reference Liping Fu, Martin Kilbinger, 2009, arXiv:0907.0795 Description We have introduced a new cosmic shear statistic which decomposes the shear correlation into E- and B-modes on a finite angular interval. The new function is calculated by integrating the shear two-point correlation function with

  •   Authors: S. Pires, J.-L. Starck, A. Amara, R. Teyssier, A. Refregier, J. Fadili Journal: MNRAS Year: 2009 Download: ADS | arXiv Abstract With increasingly large data sets, weak lensing measurements are able to measure cosmological parameters with ever greater precision. However this increased accuracy also places greater demands on the statistical tools used to extract

  •   Authors: R. Teyssier, S. Pires,  … , J.-L. Starck et al. Journal: A&A Year: 2009 Download: ADS | arXiv Abstract We have performed a 70 billion dark-matter particles N-body simulation in a 2 h−1 Gpc periodic box, using the concordance, cosmological model as favored by the latest WMAP3 results. We have computed a full-sky convergence map with

  •   Authors:  J. -L. Starck, Y. Moudden, J. Bobin Journal: Astronomy and Astrophysics Year: 2009 Download: ADS | arXiv Abstract The statistics of the temperature anisotropies in the primordial cosmic microwave background radiation field provide a wealth of information for cosmology and for estimating cosmological parameters. An even more acute inference should stem from the study of

  •   Authors: F.-X. Dupé, J. Fadili, J.-L. Starck Journal: IEEE Year: 2009 Download: ADS | arXiv Abstract In this paper, we propose a fast image deconvolution algorithm that combines adaptive block thresholding and Vaguelet-Wavelet Decomposition. The approach consists in first denoising the observed image using a wavelet-domain Stein block thresholding, and then inverting the convolution operator in the

  •   Authors: J.Bobin, J-L Starck, R. Ottensamer Journal: IEEE Year: 2008 Download: ADS | arXiv Abstract Recent advances in signal processing have focused on the use of sparse representations in various applications. A new field of interest based on sparsity has recently emerged: compressed sensing. This theory is a new sampling framework that provides an

  •   Authors: J. Bobin, Y. Moudden, J.-L. Starck, J. Fadili, N. Aghanim Journal: Statistical Methodology Year: 2008 Download: ADS | arXiv Abstract Non-negative blind source separation (BSS) has raised interest in various fields of research, as testified by the wide literature on the topic of non-negative matrix factorization (NMF). In this context, it is fundamental that

  •   Authors: J. Bobin, J.-L. Starck, Y. Moudden, J. M. Fadili Journal: AIEP Year: 2008 Download: HAL Abstract Over the last few years, the development of multi-channel sensors motivated interest in methods for the coherent processing of multivariate data. Some specific issues have already been addressed as testified by the wide literature on the so-called

  •   Authors: J. Bobin, J.-L. Starck, J. M. Fadili, Y. Moudden, D. L. Donoho Journal: IEEE Year: 2007 Download: ADS Abstract In a recent paper, a method called morphological component analysis (MCA) has been proposed to separate the texture from the natural part in images. MCA relies on an iterative thresholding algorithm, using a threshold which decreases linearly towards zero

  •   Authors: J. Bobin, J.-L. Starck, J. Fadili, Y. Moudden Journal: IEEE Year: 2007 Download: IEEE Abstract Over the last few years, the development of multichannel sensors motivated interest in methods for the coherent processing of multivariate data. Some specific issues have already been addressed as testified by the wide literature on the so-called blind source separation (BSS)

  •   Authors: J. M. Fadili, J.-L. Starck, F. Murtagh Journal: The Computer Journal Year: 2007 Download: HAL Abstract Representing the image to be inpainted in an appropriate sparse representation dictionary, and combining elements from Bayesian statistics and modern harmonic analysis, we introduce an expectation maximization (EM) algorithm for image inpainting and interpolation. From a statistical point of

  •   Authors: R. Massey, … , J.-L. Starck, …, S. Pires et al. Journal: Nature Year: 2007 Download: ADS | arXiv Abstract Ordinary baryonic particles (such as protons and neutrons) account for only one-sixth of the total matter in the Universe. The remainder is a mysterious “dark matter” component, which does not interact via electromagnetism and thus neither emits

  •   Authors: E. Saar, V. J. Martinez, J-L. Starck, D. L. Donoho Journal: MNRAS Year: 2007 Download: ADS | arXiv Abstract Many statistical methods have been proposed in the last years for analyzing the spatial distribution of galaxies. Very few of them, however, can handle properly the border effects of complex observational sample volumes. In this

  •   Authors: S. Pires, D. Yvon, Y. Moudden, S. Anthoine, E. Pierpaoli Journal: A&A Year: 2006 Download: ADS | arXiv Abstract We present a new method for the reconstruction of Sunyaev-Zel’dovich (SZ) galaxy clusters in future SZ-survey experiments using multiband bolometer cameras such as Olimpo, APEX, or Planck. Our goal is to optimise SZ-Cluster extraction from

  •   Authors: J. Bobin, Y. Moudden, J.-L. Starck, M. Elad Journal: IEEE Year: 2006 Download: IEEE Abstract This letter describes a new method for blind source separation, adapted to the case of sources having different morphologies. We show that such morphological diversity leads to a new and very efficient separation method, even in the presence of

  •   Authors: P. Lambert, S. Pires, J. Ballot, R.A. Garcia, J.-L. Starck, S. Turck-Chièze Journal: A&A Year: 2006 Download: ADS | arXiv   Abstract Context. The detection and identification of oscillation modes (in terms of their l, m, and successive n) is a great challenge for present and future asteroseismic space missions. “Peak tagging” is an important

  •   Authors: J.-L. Starck, S. Pires, Alexandre Réfrégier Journal: A&A Year: 2006 Download: ADS | arXiv   Abstract This paper presents a new method for the reconstruction of weak lensing mass maps. It uses the multiscale entropy concept, which is based on wavelets, and the False Discovery Rate which allows us to derive robust detection levels in

  •   Authors: M. Elad, J.-L. Starck, P. Querre, D.L. Donoho Journal: ACHA Year: 2005 Download: Science Direct Abstract This paper describes a novel inpainting algorithm that is capable of filling in holes in overlapping texture and cartoon image layers. This algorithm is a direct extension of a recently developed sparse-representation-based image decomposition method called MCA

  •   Authors: J.-L. Starck, M. Elad , D.L. Donoho Journal: IEEE Year: 2005 Download: IEEE Abstract This paper describes a novel inpainting algorithm that is capable of filling in holes in overlapping texture and cartoon image layers. This algorithm is a direct extension of a recently developed sparse-representation-based image decomposition method called MCA (morphological component