Measuring weak lensing masses on individual clusters

We present weak lensing mass estimates for a sample of 458 galaxy clusters from the redMaPPer Sloan Digital Sky Survey DR8 catalogue using Hyper Suprime-Cam weak lensing data. We develop a method to quickly estimate cluster masses from weak lensing shear and use this method to estimate weak lensing masses for each of the galaxy clusters in our sample. Subsequently, we constrain the mass-richness relation as well as the intrinsic scatter between the cluster richness and the measured weak lensing masses. When calculating the mass-richness relation for all clusters with a richness $\lambda>20$, we find a tension in the slope of the mass-richness relation with the Dark Energy Survey Year 1 stacked weak lensing analysis. For a reduced sample of clusters with a richness $\lambda>40$, our results are consistent with the Dark Energy Survey Year 1 analysis.Comment: 7 pages, 7 figures. Monthly Notices of the Royal Astronomical Society (2022

Recent updates on the Maser Monitoring Organisation

The Maser Monitoring Organisation (M2O) is a research community of telescope operators, astronomy researchers and maser theoreticians pursuing a joint goal of reaching a deeper understanding of maser emission and exploring its variety of uses as tracers of astrophysical events. These proceedings detail the origin, motivations and current status of the M2O, as was introduced at the 2021 EVN symposium

Finances solidaires et territoires : analyses en Bretagne et Pays-de-la-Loire

International audienceDans cet article, nous proposons une synthèse de la recherche conduite pour la Délégation Interministérielle à l’Innovation, à l’Expérimentation Sociale et à l’Économie Sociale (DIIESES) dans le cadre du programme de recherche « Finances et Monnaies Solidaires » (FIMOSOL) en 2006-2007. Nous interrogeons les dynamiques territoriales des finances solidaires en région Bretagne et Pays-de-la-Loire pour en montrer les défis et les enjeux. Pour cela, nous mobilisons l’économie des proximités et la géographie économique et sociale de façon à comprendre et expliquer les relations réflexives entre les territoires et les finances solidaires dans le Grand-Ouest de la France.</p

Finances solidaires et territoires : analyses en Bretagne et Pays-de-la-Loire

This article studies the nature of links between solidarity-based finance and territories in two French West regions : Bretagne and Pays-de-la-Loire. We show how the theoretical links must be set up in two disciplinary fields of regional and economic geographic and, of proximities economics. So, we try to examine methods and empirical studies which allow crossing those two fields for understanding the expansion of solidarity-based finance in this meta-region of French North-West. Our research program (FIMOSOL (Solidarity-based currencies and finance) was financed by the Interministerial Delegation at Social and Experimental Innovation and Social Economy (DIIESES) in 2006-2007.Solidarity-based finance, territories, regions

Impact of the calibration of the halo mass function on galaxy cluster number count cosmology

International audienceThe halo mass function (HMF) is a critical element in cosmological analyses of galaxy cluster catalogs. We quantify the impact of uncertainties in HMF parameters on cosmological constraints from cluster catalogs similar to those from Planck, those expected from the Euclid, Roman, and Rubin surveys, and from a hypothetical larger future survey. We analyze simulated catalogs in each case, gradually loosening priors on HMF parameters to evaluate the degradation in cosmological constraints. While current uncertainties on HMF parameters do not substantially impact Planck-like surveys, we find that they can significantly degrade the cosmological constraints for a Euclid-like survey. Consequently, the current precision on the HMF is not sufficient for Euclid, Roman, Rubin or possible larger surveys. Future experiments will have to properly account for uncertainties in HMF parameters, and it will be necessary to improve the precision of HMF fits to avoid weakening constraints on cosmological parameters.Key words: galaxies: clusters: general / large-scale structure of Universe / cosmological parameter

PANCO2: A new software to measure pressure profiles from resolved thermal SZ observations

International audienceWe have developed a new software to perform the measurement of galaxy cluster pressure profiles from high angular resolution thermal SZ observations. The code allows the user to take into account various features of millimeter observations, such as point spread function (PSF) convolution, pipeline filtering, correlated residual noise, and point source contamination, in a forward modeling approach. A major advantage of this software is its performance, enabling the extraction of the pressure profile and associated confidence intervals via MCMC sampling in times as short as a few minutes. We present the code and its validation on various realistic synthetic maps, of ideal spherical clusters, as well as of realistic, hydrodynamically simulated objects. We plan to publicly release the software in the coming months

Forecasting the Y500 – M500 scaling relation from the NIKA2 SZ Large Program

International audienceOne of the key elements needed to perform the cosmological exploitation of a cluster survey is the relation between the survey observable and the cluster masses. Among these observables, the integrated Compton parameter Y is a measurable quantity in Sunyaev-Zeldovich (SZ) surveys, which tightly correlates with cluster mass. The calibration of the relation between the Compton parameter Y500 and the mass M500 enclosed within radius R500 is one of the scientific goals of the NIKA2 SZ Large Program (LPSZ). We present an ongoing study to forecast the constraining power of this program, using mock simulated datasets that mimic the large program sample, selection function, and typical uncertainties on Y500 and M500. We use a Bayesian hierarchical modelling that enables taking into account a large panel of systematic effects. Our results show that the LPSZ can yield unbiased estimates of the scaling relation parameters for realistic input parameter values. The relative uncertainties on these parameters is ~ 10% for the intercept and slope of the scaling relation, and ~ 34% for its intrinsic scatter, foreshadowing precise estimates to be delivered by the LPSZ

Label-free detection of mitochondrial activity with Microwave Dielectric Spectroscopy Research Article

International audienceMitochondrial bioenergetics contributes to important biological processes and its dysfunction underlies some diseases, but its assessment requires invasive methods involving intracellular staining and chemical inhibitors. In this study, we introduce microwave dielectric spectroscopy (MWDS) as a new non-invasive and label-free method to detect mitochondrial activity in live cells. We show that under electromagnetic radiation with microwaves (0.4-40 GHz), the dielectric properties of living cells are determined by their mitochondrial activity. MWDS instantly detects the mitochondrial depolarization induced by drugs targeting electron transport chain complexes or during the earliest events of the apoptotic process, from a cell suspension of a single microliter. MWDS also discriminates cancer cells with higher mitochondrial activity, an aspect often related to therapeutic resistance in cancer. Thereby, MWDS represents a highly innovative method for non-invasive detection of mitochondrial activity in live cells, with a broad range of applications in biology and medicine

Label-free detection of mitochondrial activity with Microwave Dielectric Spectroscopy Research Article

International audienceMitochondrial bioenergetics contributes to important biological processes and its dysfunction underlies some diseases, but its assessment requires invasive methods involving intracellular staining and chemical inhibitors. In this study, we introduce microwave dielectric spectroscopy (MWDS) as a new non-invasive and label-free method to detect mitochondrial activity in live cells. We show that under electromagnetic radiation with microwaves (0.4-40 GHz), the dielectric properties of living cells are determined by their mitochondrial activity. MWDS instantly detects the mitochondrial depolarization induced by drugs targeting electron transport chain complexes or during the earliest events of the apoptotic process, from a cell suspension of a single microliter. MWDS also discriminates cancer cells with higher mitochondrial activity, an aspect often related to therapeutic resistance in cancer. Thereby, MWDS represents a highly innovative method for non-invasive detection of mitochondrial activity in live cells, with a broad range of applications in biology and medicine

The SRG/eROSITA All-Sky Survey: Weak-Lensing of eRASS1 Galaxy Clusters in KiDS-1000 and Consistency Checks with DES Y3 & HSC-Y3

International audienceWe aim to participate in the calibration of the X-ray photon count rate to halo mass scaling relation of galaxy clusters selected in the first eROSITA All-Sky Survey on the Western Galactic Hemisphere (eRASS1) using KiDS-1000 weak-lensing (WL) data. We measure the radial shear profiles around eRASS1 galaxy clusters using background galaxies in KiDS-1000, as well as the cluster member contamination. Furthermore we provide consistency checks with the other stage-III WL surveys who take part in the eRASS1 mass calibration, DES Y3 and HSC-Y3. We determine the cluster member contamination of eRASS1 clusters present in KiDS-1000 based on source number density profiles, where we account for the obscuration caused by cluster galaxies. The extracted shear profiles, together with the contamination model and the lens sample selection, are then analysed through a Bayesian population model. We calibrate the WL mass bias parameter by analysing realistic synthetic shear profiles from mock cluster catalogues. Our consistency checks between KiDS-1000 and DES Y3 & HSC-Y3 include the comparison of contamination-corrected density contrast profiles employing the union of background sources around common clusters, as well as the individual scaling relation results. We present a global contamination model for eRASS1 clusters in KiDS-1000 and the calibration results of the X-ray photon count rate to halo mass relation. The results of the WL mass bias parameter show that the uncertainty of the multiplicative shear bias dominates the systematic error budget at low clusters redshifts while the uncertainty of our contamination model does at high ones. The cross-checks between the three WL surveys show that they are statistically consistent with each other. This enables for the first time cosmological constraints from clusters calibrated by three state-of-the-art WL surveys. (abridged