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Introduction. Des missionnaires aux prêtres locaux : enjeux et défis de l’africanisation du clergé catholique, de la fin du XIXe siècle au début des années 1960
No full textInternational audienceThe papers gathered here look at a major element in the transformation of the Catholic missionary model in sub-Saharan Africa and its entry into the period of decolonisation: the development of native clergy. The dossier evokes the attempts made at the end of the 19th century and focuses on the turning point at the end of the colonial era, from the 1930s to the early 1960s. It highlights the multiplicity of players involved: encouraged by the pontifical authorities, the gradual access of native priests to positions of responsibility in the missionary organisation was accepted under constraint by the missionaries, who were persuaded to delay the move by racial prejudice and the desire to maintain a dominant position in colonial society. The main aim of this dossier is to highlight, from a transnational perspective, members of the clergy in sub-Saharan Africa as players in the religious, as well as the social, political and cultural history of the end of the colonial period and the beginning of the era of decolonisation.Les contributions rassemblées ici se penchent sur un élément majeur de la transformation du modèle missionnaire catholique en Afrique subsaharienne et de son entrée dans la période de la décolonisation : le développement du clergé local. Le dossier évoque les tentatives de la fin du XIX e siècle et se concentre sur le tournant que constitue la fin de l’époque coloniale, des années 1930 au début des années 1960. Il met en valeur la multiplicité des acteurs : encouragé par le pouvoir pontifical, l’accès progressif des prêtres autochtones à des responsabilités dans l’organisation missionnaire est accepté de manière contrainte par les missionnaires, que les préjugés raciaux et la volonté de maintenir une position dominante dans la société coloniale convainquent de retarder le mouvement. La mise en évidence, dans une perspective transnationale, des membres du clergé d’Afrique subsaharienne comme acteurs de l’histoire religieuse, mais aussi sociale, politique et culturelle de la fin de la période coloniale et de l’entrée dans l’ère de la décolonisation, est l’objectif principal du dossier
Euclid Quick Data Release (Q1): From spectrograms to spectra: the SIR spectroscopic Processing Function
No full textInternational audienceThe Euclid space mission aims to investigate the nature of dark energy and dark matter by mapping the large-scale structure of the Universe. A key component of Euclid's observational strategy is slitless spectroscopy, conducted using the Near Infrared Spectrometer and Photometer (NISP). This technique enables the acquisition of large-scale spectroscopic data without the need for targeted apertures, allowing precise redshift measurements for millions of galaxies. These data are essential for Euclid's core science objectives, including the study of cosmic acceleration and the evolution of galaxy clustering, as well as enabling many non-cosmological investigations. This study presents the SIR processing function (PF), which is responsible for processing slitless spectroscopic data. The objective is to generate science-grade fully-calibrated one-dimensional spectra, ensuring high-quality spectroscopic data. The processing function relies on a source catalogue generated from photometric data, effectively corrects detector effects, subtracts cross-contaminations, minimizes self-contamination, calibrates wavelength and flux, and produces reliable spectra for later scientific use. The first Quick Data Release (Q1) of Euclid's spectroscopic data provides approximately three million validated spectra for sources observed in the red-grism mode from a selected portion of the Euclid Wide Survey. We find that wavelength accuracy and measured resolving power are within requirements, thanks to the excellent optical quality of the instrument. The SIR PF represents a significant step in processing slitless spectroscopic data for the Euclid mission. As the survey progresses, continued refinements and additional features will enhance its capabilities, supporting high-precision cosmological and astrophysical measurements
Effect of halide ions on photoproduction of excited triplet-state of dissolved organic matter in seawater
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Austérité sanitaire Face à l’érosion de l’économie fondamentale dans les espaces délaissés
No full textInternational audienceSmall and medium-sized cities have long been sidelined in urban research. However,they have recently come to the forefront of media, political and academic debate. Thenotion of “left-behind places” questions the rise of territorial inequalities that lead tothe marginalisation of territories previously integrated into national dynamics, but alsothe political and social consequences of these developments.The article presents two cities that can be considered as left-behind: Roanne, amedium-sized city of 34,000 inhabitants, and La Grand-Combe, a small town of5,000 inhabitants. In a French context where the withdrawal of the state is perceptiblein a number of spheres of public action, the article is based on the analysis of a keysector of the “fundamental economy”: healthcare. The study of the evolution of thissector allows us to refine the analysis of the austerity policies implemented in France.These policies are characterised less by spectacular cuts in funding than by a slowerosion of the workforce, an unequal distribution of resources and a concentration ofsupply that affects access to care.Longtemps restées à la marge de la recherche urbaine, les villes petites et moyennesse sont récemment imposées dans les débats médiatiques, politiques et académiques.La notion d’« espaces délaissés » permet d’interroger la montée des inégalitésterritoriales qui conduisent à la marginalisation de territoires auparavant intégrés dansles dynamiques nationales, mais aussi les conséquences politiques et sociales de cesévolutions.L’article présente deux villes en déclin : Roanne, une ville moyenne de 34 000 habitantset La Grand-Combe, une petite ville de moins de 5 000 habitants. Dans un contextefrançais où le retrait de l’État est perceptible dans un ensemble de sphères de l’actionpublique, ce texte s’appuie sur l’analyse d’un secteur clé de l’« économiefondamentale » : la santé. L’étude des évolutions de ce secteur permet d’affiner celledes politiques d’austérité mises en oeuvre en France. Celles-ci se caractérisent moinspar des coupes spectaculaires dans les dotations que par une lente érosion deseffectifs, une inégale répartition des ressources, et une concentration de l’offre quiaffecte l’accès aux soins
Evidence of medium response to hard probes using correlations of Z bosons with hadrons in heavy ion collisions
No full textInternational audienceThe first measurement of pseudorapidity and azimuthal angle distributions relative to the momentum vector of a Z boson for low transverse momentum () charged hadrons in lead-lead (PbPb) collisions is presented. By studying the hadrons produced in an event with a high- Z boson (40 350 GeV), the analysis probes how the quark-gluon plasma (QGP) medium created in these collisions affects the parton recoiling opposite to the Z boson. Utilizing PbPb data at a nucleon-nucleon center-of-mass energy = 5.02 TeV from 2018 with an integrated luminosity of 1.67 nb and proton-proton (pp) data at the same energy from 2017 with 301 pb, the distributions are examined in bins of charged-hadron . A significant modification of the distributions for charged hadrons in the range 1 2 GeV in PbPb collisions is observed when compared to reference measurements from pp collisions. The data provide new information about the correlation between hard and soft particles in heavy ion collisions, which can be used to test predictions of various jet quenching models. The results are consistent with expectations of a hydrodynamic wake created when the QGP is depleted of energy by the parton propagating through it. Based on comparisons of PbPb data with pp references and predictions from theoretical models, this Letter presents the first evidence of medium-recoil and medium-hole effects caused by a hard probe
Euclid: Methodology for derivation of IPC-corrected conversion gain of nonlinear CMOS APS
No full textInternational audienceWe introduce a fast method to measure the conversion gain in Complementary Metal-Oxide-Semiconductors (CMOS) Active Pixel Sensors (APS), which accounts for nonlinearity and interpixel capacitance (IPC). The standard 'mean-variance' method is biased because it assumes pixel values depend linearly on signal, and existing methods to correct for nonlinearity are still introducing significant biases. While current IPC correction methods are prohibitively slow for a per-pixel application, our new method uses separate measurements of the IPC kernel to make an almost instantaneous calculation of gain. Validated using test data from a flight detector from the ESA Euclid mission, the IPC correction recovers the results of slower methods within 0.1% accuracy. Meanwhile the nonlinearity correction ensures an estimation of the gain that is independent of signal, correcting a bias of more than 2.5% on gain estimation
ZTF SN Ia DR2 follow-up: Exploring the origin of the Type Ia supernova host galaxy step through Si II velocities
No full textInternational audienceThe relationship between Type Ia supernovae (SNe Ia) and their host galaxy stellar masses is well documented. In particular, Hubble residuals display a luminosity shift based on host mass, known as the mass step, which is often used as an extra correction in the standardisation of SN Ia luminosities. Here we investigate Hubble residuals and the mass step in the context of Si II velocities, using 277 near-peak SNe Ia from ZTF DR2. We divide the sample into high-velocity (HV) and normal-velocity (NV) SNe Ia, separated at 12,000 km/s, resulting in 70 HV and 207 NV objects. We then examine links between Si II 6355 velocities, light-curve stretch , colour , and host properties to explore potential environmental and/or progenitor-related effects. Although we only find a marginal difference between the Hubble residuals of HV and NV SNe Ia, the NV mass step is mag (), while HV SNe Ia show mag (), consistent with zero. The NV-HV mass-step difference is . The clearest subtype difference is seen in central regions (), while NV SNe show stronger environmental trends. Thus, NV SNe Ia appear more environmentally sensitive, especially in central, likely metal-rich and older regions, while HV SNe Ia show weaker, subset-dependent trends, and applying a universal mass-step correction could introduce biases. Refined classifications or environment-dependent factors may improve future cosmological analyses beyond standard and cuts