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Les antinomies du droit de résistance
No full textInternational audienceيثير حق المقاومة تناقضًا كبيرًا: كيف يمكن لنظام قانوني أن يدمج معارضته الخاصة؟ يصعب إثبات هذا الحق أمام القضاء، ويبدو أنه لا يكتسب أهميته إلا بعد انتصار الثورة. إن طبيعته المعيارية غير مؤكدة، وشرعيته تعتمد على نظرة التاريخ إليه. تجسد المقاومة الفرنسية، والمسيرة على قصر بوربون في عام 1934، أو الهجوم على مبنى الكابيتول في عام 2021، هذه التناقضات: فالأطراف الفاعلة تنظر إلى نفسها دائمًا على أنها مقاومة، لكن قضاياها تختلف اختلافًا جذريًا.تُظهر شخصية أنتيجون أن العصيان والمقاومة لا يمكن الخلط بينهما: فهي تتحدى القانون باسم نظام أعلى، لكنها تقبل تحمل العواقب دون السعي إلى الإطاحة بالسلطة. وبالتالي، يظل العصيان في إطار القانون القائم، على عكس المقاومة العنيفة التي تهدف إلى تدمير النظام.تاريخياً، بلورت الثورة الفرنسية التوترات بين الطبيعية (روبسبير) والوضعية (كوندورسيه). كان مشروع الجيرونديين يضع إطاراً قانونياً للمقاومة؛ لكن الجبليين عارضوا ذلك بشدة، معتبرين أن حق المقاومة المقنن لم يعد حقاً حقيقياً. أقرت إعلان 1793 هذا الحق في المادة 35، دون شروط أو تعريف، قبل أن يختفي في عام 1795 مع دستور المديرية، مما يمثل انتصار القانون الوضعي على الطبيعية الثورية.ومنذ ذلك الحين، إذا تم التذرع بحق المقاومة كمبدأ، فإنه لا يصبح ساريًا إلا بعد الإطاحة بالنظام القديم. لذلك، فهو ليس حقًا رسميًا بقدر ما هو فعل تاريخي جذري، تم إقراره لاحقًا وحمايته من قبل المنتصرين. إن إضفاء الطابع الرسمي على هذا الحق يعادل محاولة إضفاء الشرعية على ما هو، في جوهره، خارج الإطار القانوني.Das Recht auf Widerstand wirft einen großen Widerspruch auf: Wie kann eine Rechtsordnung ihre eigene Anfechtung integrieren? Dieses Recht ist schwer justiziabel und scheint erst nachträglich, nach dem Sieg der Revolte, Bedeutung zu erlangen. Seine Normativität ist ungewiss, seine Legitimität hängt von der Sichtweise der Geschichte ab. Der französische Widerstand, der Marsch auf den Palais Bourbon 1934 oder der Sturm auf das Kapitol 2021 veranschaulichen diese Ambivalenz: Die Akteure sehen sich immer als Widerstandskämpfer, aber ihre Anliegen unterscheiden sich radikal voneinander.Die Figur der Antigone zeigt, dass Ungehorsam und Widerstand nicht gleichzusetzen sind: Sie widersetzt sich dem Gesetz im Namen einer höheren Ordnung, akzeptiert aber die Konsequenzen, ohne zu versuchen, die Macht zu stürzen. Ungehorsam bleibt also im Rahmen des bestehenden Rechts, im Gegensatz zum gewaltsamen Widerstand, der darauf abzielt, eine Ordnung zu zerstören.Historisch gesehen kristallisieren sich in der Französischen Revolution die Spannungen zwischen Naturalismus (Robespierre) und Positivismus (Condorcet) heraus. Das Projekt der Girondisten sah einen legalen Rahmen für den Widerstand vor; die Montagnards lehnten dies vehement ab, da sie der Meinung waren, dass ein legalisiertes Recht auf Widerstand kein echtes Recht mehr sei. Die Erklärung von 1793 verankert dieses Recht in Artikel 35 ohne Bedingungen oder Definitionen, bevor es 1795 mit der Verfassung des Direktoriums verschwindet, was den Sieg des positiven Rechts über den revolutionären Naturrechtstalentismus markiert.Wenn das Recht auf Widerstand als Prinzip geltend gemacht wird, wird es daher erst nach dem Sturz der alten Ordnung tatsächlich wirksam. Es handelt sich also weniger um ein formalisiertes Recht als um einen historischen Bruch, der nachträglich von den Siegern bestätigt und sanktioniert wurde. Die Formalisierung dieses Rechts kommt dem Versuch gleich, etwas zu legalisieren, was seinem Wesen nach außerhalb des rechtlichen Rahmens liegt.The right to resist raises a major contradiction: how can a legal system incorporate its own challenge? Difficult to enforce, this right seems to only gain significance ex post, once the revolt has been victorious. Its normativity is uncertain, its legitimacy dependent on how history views it. The French Resistance, the march on the Palais Bourbon in 1934 and the storming of the Capitol in 2021 illustrate this ambivalence: the actors always see themselves as resisters, but their causes diverge radically.The figure of Antigone shows that disobedience and resistance are not the same thing: she challenges the law in the name of a higher order but accepts the consequences without seeking to overthrow the authorities. Disobedience therefore remains within the framework of existing law, unlike violent resistance, which aims to destroy an order.Historically, the French Revolution crystallised the tensions between naturalism (Robespierre) and positivism (Condorcet). The Girondin project framed resistance through legal channels; the Montagnards fiercely opposed this, believing that a legalised right to resistance was no longer a real right. The Declaration of 1793 enshrined this right in Article 35, without conditions or definitions, before it disappeared in 1795 with the Constitution of the Directory, marking the victory of positive law over revolutionary jusnaturalism.From then on, although the right to resist was invoked as a principle, it only became effective once the old order had been overthrown. It was therefore less a formalised right than an act of historical rupture, validated a posteriori and sanctified by the victors. Formalising this right amounts to attempting to make legal what, by its very nature, falls outside the legal framework.El derecho a la resistencia plantea una contradicción importante: ¿cómo puede un orden jurídico integrar su propia contestación? Difícilmente justiciable, este derecho parece adquirir relevancia solo a posteriori, una vez que la revuelta ha triunfado. Su normatividad es incierta y su legitimidad depende de la visión que tenga la historia. La Resistencia francesa, la marcha sobre el Palacio Bourbon de 1934 o el asalto al Capitolio en 2021 ilustran esta ambivalencia: los actores siempre se perciben a sí mismos como resistentes, pero sus causas divergen radicalmente.La figura de Antígona muestra que la desobediencia y la resistencia no son lo mismo: ella desafía la ley en nombre de un orden superior, pero acepta sufrir las consecuencias, sin intentar derrocar al poder. La desobediencia se mantiene, por tanto, dentro del marco de la ley vigente, a diferencia de la resistencia, violenta, que pretende destruir un orden.Históricamente, la Revolución Francesa cristaliza las tensiones entre el naturalismo (Robespierre) y el positivismo (Condorcet). El proyecto girondino enmarcaba la resistencia por vías legales; los montagnards se opusieron ferozmente a ello, considerando que un derecho de resistencia legalizado ya no era un derecho real. La Declaración de 1793 consagra este derecho en su artículo 35, sin condiciones ni definiciones, antes de que desapareciera en 1795 con la Constitución del Directorio, lo que supuso la victoria del derecho positivo sobre el jusnaturalismo revolucionario.A partir de entonces, si bien el derecho de resistencia se invoca como principio, solo se hace efectivo una vez derrocado el antiguo orden. Por lo tanto, se trata menos de un derecho formalizado que de un acto de ruptura histórica, validado a posteriori y santificado por los vencedores. Formalizar este derecho equivale a intentar legalizar lo que, por esencia, escapa al marco legal.Le droit de résistance soulève une contradiction majeure : comment un ordre juridique peut-il intégrer sa propre contestation ? Difficilement justiciable, ce droit semble n’acquérir de portée qu’ex post, une fois la révolte victorieuse. Sa normativité est incertaine, sa légitimité dépendante du regard que porte l’histoire. La Résistance française, la marche sur le Palais Bourbon de 1934 ou l’assaut du Capitole en 2021 illustrent cette ambivalence : les acteurs se perçoivent toujours comme résistants, mais leurs causes, elles, divergent radicalement.La figure d’Antigone montre que désobéissance et résistance ne se confondent pas : elle conteste la loi au nom d’un ordre supérieur mais accepte d’en subir les conséquences, sans chercher à renverser le pouvoir. La désobéissance reste donc dans le cadre du droit existant, contrairement à la résistance, violente, qui vise à détruire un ordre.Historiquement, la Révolution française cristallise les tensions entre naturalisme (Robespierre) et positivisme (Condorcet). Le projet girondin encadrait la résistance par des voies légales ; les Montagnards s’y opposèrent farouchement, estimant qu’un droit de résistance légalisé n’était plus un droit réel. La Déclaration de 1793 consacre ce droit dans l’article 35, sans condition ni définition, avant qu’il ne disparaisse en 1795 avec la Constitution du Directoire, marquant la victoire du droit positif sur le jusnaturalisme révolutionnaire.Dès lors, si le droit de résistance est invoqué comme principe, il ne devient opérant qu’en fait, une fois l’ordre ancien renversé. C’est donc moins un droit formalisé qu’un acte de rupture historique, validé a posteriori et sanctuarisé par les vainqueurs. Formaliser ce droit revient à tenter de rendre légal ce qui, par essence, échappe au cadre légal.Il diritto alla resistenza solleva una contraddizione fondamentale: come può un ordinamento giuridico integrare la propria contestazione? Difficilmente giustiziabile, questo diritto sembra acquisire rilevanza solo a posteriori, una volta che la rivolta ha avuto successo. La sua normatività è incerta, la sua legittimità dipende dal giudizio della storia. La Resistenza francese, la marcia sul Palazzo Bourbon del 1934 o l'assalto al Campidoglio nel 2021 illustrano questa ambivalenza: gli attori si percepiscono sempre come resistenti, ma le loro cause divergono radicalmente.La figura di Antigone dimostra che disobbedienza e resistenza non sono la stessa cosa: lei contesta la legge in nome di un ordine superiore, ma accetta di subirne le conseguenze, senza cercare di rovesciare il potere. La disobbedienza rimane quindi nell'ambito del diritto esistente, a differenza della resistenza, violenta, che mira a distruggere un ordine.Storicamente, la Rivoluzione francese cristallizza le tensioni tra naturalismo (Robespierre) e positivismo (Condorcet). Il progetto girondino inquadrava la resistenza attraverso vie legali; i Montagnardi si opposero ferocemente, ritenendo che un diritto di resistenza legalizzato non fosse più un diritto reale. La Dichiarazione del 1793 sancisce questo diritto nell'articolo 35, senza condizioni né definizioni, prima che scompaia nel 1795 con la Costituzione del Direttorio, segnando la vittoria del diritto positivo sul jusnaturismo rivoluzionario.Da allora, se il diritto di resistenza viene invocato come principio, esso diventa effettivo solo una volta rovesciato l'ordine antico. Si tratta quindi meno di un diritto formalizzato che di un atto di rottura storica, convalidato a posteriori e sancito dai vincitori. Formalizzare questo diritto equivale a tentare di rendere legale ciò che, per sua natura, sfugge al quadro giuridico.O direito à resistência levanta uma grande contradição: como é que um ordenamento jurídico pode integrar a sua própria contestação? Difícilmente justiciável, este direito parece adquirir significado apenas ex post, uma vez que a revolta é vitoriosa. A sua normatividade é incerta, a sua legitimidade depende do olhar que a história lhe atribui. A Resistência francesa, a marcha sobre o Palácio Bourbon em 1934 ou o assalto ao Capitólio em 2021 ilustram essa ambivalência: os atores sempre se percebem como resistentes, mas suas causas divergem radicalmente.A figura de Antígona mostra que desobediência e resistência não são a mesma coisa: ela contesta a lei em nome de uma ordem superior, mas aceita sofrer as consequências, sem tentar derrubar o poder. A desobediência permanece, portanto, dentro do quadro da lei existente, ao contrário da resistência, violenta, que visa destruir uma ordem.Historicamente, a Revolução Francesa cristalizou as tensões entre o naturalismo (Robespierre) e o positivismo (Condorcet). O projeto girondino enquadrava a resistência por vias legais; os montagnards opuseram-se ferozmente, considerando que um direito de resistência legalizado já não era um direito real. A Declaração de 1793 consagra esse direito no artigo 35, sem condições nem definições, antes de desaparecer em 1795 com a Constituição do Diretório, marcando a vitória do direito positivo sobre o jusnaturalismo revolucionário.A partir de então, se o direito de resistência é invocado como princípio, ele só se torna operante de facto, uma vez derrubada a antiga ordem. Trata-se, portanto, menos de um direito formalizado do que de um ato de ruptura histórica, validado a posteriori e santificado pelos vencedores. Formalizar esse direito equivale a tentar tornar legal o que, por essência, escapa ao quadro legal.Право на сопротивление вызывает серьезное противоречие: как правовая система может включать в себя собственное оспаривание? Это право, которое трудно поддается судебному разбирательству, кажется, приобретает значение только задним числом, после победы восстания. Его нормативность неопределенна, а легитимность зависит от того, как на него смотрит история. Французское Сопротивление, марш на Дворец Бурбонов в 1934 году или штурм Капитолия в 2021 году иллюстрируют эту амбивалентность: участники всегда воспринимают себя как сопротивленцев, но их причины радикально различаются.Фигура Антигоны показывает, что неповиновение и сопротивление не тождественны: она оспаривает закон во имя высшего порядка, но соглашается понести последствия, не пытаясь свергнуть власть. Таким образом, неповиновение остается в рамках существующего права, в отличие от насильственного сопротивления, которое направлено на разрушение порядка.Исторически Французская революция кристаллизует противоречия между натурализмом (Робеспьер) и позитивизмом (Кондорсе). Проект жирондистов ограничивал сопротивление законными средствами; монтаньяры яростно противостояли этому, считая, что узаконенное право на сопротивление больше не является реальным правом. Декларация 1793 года закрепила это право в статье 35 без каких-либо условий или определений, но в 1795 году оно исчезло с принятием Конституции Директории, что ознаменовало победу позитивного права над революционным натурализмом.С тех пор, если право на сопротивление заявляется как принцип, оно становится действующим только после свержения старого порядка. Таким образом, это не столько формализованное право, сколько акт исторического разрыва, утвержденный задним числом и закрепленный победителями. Формализация этого права равносильна попытке узаконить то, что по сути своей выходит за рамки закона.抵抗权引发了一个重大矛盾：一个法律体系如何能够纳入对自身的挑战？这一权利难以通过司法途径实现，似乎只有在起义胜利后才能获得效力。其规范性存疑，其合法性则取决于历史的评判。法国抵抗运动、1934年对波旁宫的进军以及2021年对国会大厦的冲击，都体现了这种矛盾性：参与者始终认为自己是抵抗者，但他们的诉求却截然不同。安提戈涅的形象表明，不服从与抵抗并非同一回事：她以更高的秩序为名挑战法律，但愿意承受后果，而不试图推翻权力。因此，不服从仍处于现有法律的框架内，而暴力抵抗则旨在摧毁现有秩序。从历史上看，法国大革命集中体现了自然主义（罗伯斯庇尔）与实证主义（孔多塞）之间的矛盾。吉伦特派的计划通过法律途径规范抵抗行为；山岳派对此表示强烈反对，认为合法化的抵抗权已不再是真正的权利。1793年的《宣言》在第35条中明确了这一权利，没有附加任何条件或定义，但在1795年随着《督政府宪法》的出台，这一权利消失了，标志着实证法对革命自然法的胜利。此后，尽管抵抗权被作为原则提出，但它实际上只有在旧秩序被推翻后才生效。因此，它更像是一次历史性的断裂行为，事后由胜利者予以认可并神圣化。将这一权利形式化，无异于试图将本质上超出法律框架的事物合法化
Euclid preparation. Sensitivity to non-standard particle dark matter model
No full textInternational audienceThe Euclid mission of the European Space Agency will provide weak gravitational lensing and galaxy clustering surveys that can be used to constrain the standard cosmological model and its extensions, with an opportunity to test the properties of dark matter beyond the minimal cold dark matter paradigm. We present forecasts from the combination of these surveys on the parameters describing four interesting and representative non-minimal dark matter models: a mixture of cold and warm dark matter relics; unstable dark matter decaying either into massless or massive relics; and dark matter experiencing feeble interactions with relativistic relics. We model these scenarios at the level of the non-linear matter power spectrum using emulators trained on dedicated N-body simulations. We use a mock Euclid likelihood to fit mock data and infer error bars on dark matter parameters marginalised over other parameters. We find that the Euclid photometric probe (alone or in combination with CMB data from the Planck satellite) will be sensitive to the effect of each of the four dark matter models considered here. The improvement will be particularly spectacular for decaying and interacting dark matter models. With Euclid, the bounds on some dark matter parameters can improve by up to two orders of magnitude compared to current limits. We discuss the dependence of predicted uncertainties on different assumptions: inclusion of photometric galaxy clustering data, minimum angular scale taken into account, modelling of baryonic feedback effects. We conclude that the Euclid mission will be able to measure quantities related to the dark sector of particle physics with unprecedented sensitivity. This will provide important information for model building in high-energy physics. Any hint of a deviation from the minimal cold dark matter paradigm would have profound implications for cosmology and particle physics
Euclid preparation. Exploring the properties of proto-clusters in the Simulated Euclid Wide Survey
No full textInternational audienceGalaxy proto-clusters are receiving an increased interest since most of the processes shaping the structure of clusters of galaxies and their galaxy population are happening at early stages of their formation. The Euclid Survey will provide a unique opportunity to discover a large number of proto-clusters over a large fraction of the sky (14 500 square degrees). In this paper, we explore the expected observational properties of proto-clusters in the Euclid Wide Survey by means of theoretical models and simulations. We provide an overview of the predicted proto-cluster extent, galaxy density profiles, mass-richness relations, abundance, and sky-filling as a function of redshift. Useful analytical approximations for the functions of these properties are provided. The focus is on the redshift range z= 1.5 to 4. We discuss in particular the density contrast with which proto-clusters can be observed against the background in the galaxy distribution if photometric galaxy redshifts are used as supplied by the ESA Euclid mission together with the ground-based photometric surveys. We show that the obtainable detection significance is sufficient to find large numbers of interesting proto-cluster candidates. For quantitative studies, additional spectroscopic follow-up is required to confirm the proto-clusters and establish their richness
Amplitude analysis of decays
No full textInternational audienceThe first full amplitude analysis of decays is performed using proton-proton collision data corresponding to an integrated luminosity of recorded with the LHCb detector. The rich spectrum is studied and the branching fractions of the resonant substructure associated with the prominent contribution are measured. The data cannot be described by conventional strange and charmonium resonances only. An amplitude model with 53 components is developed comprising 11 hidden-charm exotic hadrons. New production mechanisms for charged charmonium-like states are observed. Significant resonant activity with spin-parity in the system is confirmed and a multi-pole structure is demonstrated. The spectral decomposition of the invariant-mass structure, dominated by decays, broadly resembles the spectrum observed in decays. Exotic resonances are observed for the first time
ZTF SN Ia DR2: Peculiar velocities impact on the Hubble diagram
No full textInternational audienceSNe Ia are used to determine the distance-redshift relation and build the Hubble diagram. Neglecting their host-galaxy peculiar velocities (PVs) may bias the measurement of cosmological parameters. The smaller the redshift, the larger the effect is. We use realistic simulations of SNe Ia observed by the Zwicky Transient Facility (ZTF) to investigate the effect of different methods to take into account PVs. We study the impact of neglecting galaxy PVs and their correlations in an analysis of the SNe Ia Hubble diagram. We find that it is necessary to use the PV full covariance matrix computed from the velocity power spectrum to take into account the sample variance. Considering the results we have obtained using simulations, we determine the PV systematic effects in the context of the ZTF DR2 SNe Ia sample. We determine the PV impact on the intercept of the Hubble diagram, , which is directly linked to the measurement of . We show that not taking into account PVs and their correlations results in a shift of the value of about km.s.Mpc and a slight underestimation of the error bar
Euclid: Early Release Observations -- Unveiling the morphology of two Milky Way globular clusters out to their periphery
No full textInternational audienceAs part of the Euclid Early Release Observations (ERO) programme, we analyse deep, wide-field imaging from the VIS and NISP instruments of two Milky Way globular clusters (GCs), namely NGC 6254 (M10) and NGC 6397, to look for observational evidence of their dynamical interaction with the Milky Way. We search for such an interaction in the form of structural and morphological features in the clusters' outermost regions, which are suggestive of the development of tidal tails on scales larger than those sampled by the ERO programme. Our multi-band photometric analysis results in deep and well-behaved colour-magnitude diagrams that, in turn, enable an accurate membership selection. The surface brightness profiles built from these samples of member stars are the deepest ever obtained for these two Milky Way GCs, reaching down to mag~arcsec, which is about mag arcsec below the current limit. The investigation of the two-dimensional density map of NGC 6254 reveals an elongated morphology of the cluster peripheries in the direction and with the amplitude predicted by -body simulations of the cluster's dynamical evolution, at high statistical significance. We interpret this as strong evidence for the first detection of tidally induced morphological distortion around this cluster. The density map of NGC 6397 reveals a slightly elliptical morphology, in agreement with previous studies, which requires further investigation on larger scales to be properly interpreted. This ERO project thus demonstrates the power of Euclid in studying the outer regions of GCs at an unprecedented level of detail, thanks to the combination of large field of view, high spatial resolution, and depth enabled by the telescope. Our results highlight the future Euclid survey as the ideal data set to investigate GC tidal tails and stellar streams
Un atelier collaboratif réflexif sur les narratifs en agroécologie et les postures de recherche
No full textVersion "manuscrit auteur accepté". À paraître dans Natures Sciences Sociétés (2024, 32, 4) sous licence CC-BY - En attente de la préparation de copie avant publicationInternational audienceAgroecology has multiple interpretations and goals, driven by social movements, political contexts, and scientific needs. In this paper, we analyse a reflexive workshop that explored how agroecology narratives challenge researchers in supporting its implementation. While diverse interpretations and goals enrich the field, they can also lead to conflict. Researchers must navigate the tension between social activism and evidence-based policy solutions. The study findings highlight the need for creating new researcher profiles, including facilitators in long-term partnerships, establishing clear expectations, and developing "third spaces" for collaboration. Qualitative research assessment and new epistemological approaches are crucial for sustainable science that bridges the gap between knowledge and local realities in agroecological transitions.L’agroécologie est un terme polysémique qui peut être porté par des courants parfois contradictoires. Les processus de transition agroécologique induisent des tensions entre les initiatives enracinées dans les mouvements sociaux et les processus d'institutionnalisation. Les chercheurs sont ainsi tiraillés entre deux tâches potentiellement contradictoires : (i) conseiller les décideurs politiques et (ii) soutenir les agriculteurs et les parties prenantes dans leurs trajectoires endogènes. Cet article aborde cette tension en se concentrant sur le rôle des scientifiques dans les collaborations transdisciplinaires à long terme. L'étude passe en revue un atelier transdisciplinaire de deux jours organisés par la communauté de savoirs "Terres et Sols" (CoSav Terresol) qui est portée par l'Institut national français de recherche pour le développement durable (IRD). Les 40 participants, comprenant principalement des chercheuses et chercheurs, mais aussi des agricultrices, des représentantes d’ONG et des représentants des décideurs politiques, se sont engagés dans des activités réflexives et des ateliers collaboratifs afin de partager leurs expériences et d'explorer les différents narratifs de l'agroécologie et les postures de recherche impliquées dans des transitions agroécologiques. Les résultats soulignent le besoin de compétences transversales et de facilitateurs pour aider les scientifiques à dialoguer avec les différentes parties prenantes. Cela inclut la nécessité de questionner les narratifs et de considérer les implications éthiques des partenariats à long terme dans la production de connaissances agroécologiques
Euclid Quick Data Release (Q1): VIS processing and data products
No full textInternational audienceThis paper describes the VIS Processing Function (VIS PF) of the Euclid ground segment pipeline, which processes and calibrates raw data from the VIS camera. We present the algorithms used in each processing element, along with a description of the on-orbit performance of VIS PF, based on Performance Verification (PV) and Q1 data. We demonstrate that the principal performance metrics (image quality, astrometric accuracy, photometric calibration) are within pre-launch specifications. The image-to-image photometric scatter is less than , and absolute astrometric accuracy compared to Gaia is mas Image quality is stable over all Q1 images with a full width at half maximum (FWHM) of . The stacked images (combining four nominal and two short exposures) reach (, measured as the variance of diameter apertures). We also describe quality control metrics provided with each image, and an appendix provides a detailed description of the provided data products. The excellent quality of these images demonstrates the immense potential of Euclid VIS data for weak lensing. VIS data, covering most of the extragalactic sky, will provide a lasting high-resolution atlas of the Universe
Euclid Quick Data Release (Q1). The active galaxies of Euclid
No full textInternational audienceWe present a catalogue of candidate active galactic nuclei (AGN) in the Quick Release (Q1) fields. For each source we collect multi-wavelength photometry and spectroscopy information from Galaxy Evolution Explorer (GALEX), , Dark Energy Survey (DES), Wise-field Infrared Survey Explorer (WISE), , Dark Energy Survey (DESI), and Sloan Digital Sky Survey (SDSS), including spectroscopic redshift from public compilations. We investigate the AGN contents of the Q1 fields by applying selection criteria using colours and WISE-AllWISE cuts finding respectively 292,222 and 65,131 candidates. We also create a high-purity QSO catalogue based on DR3 information containing 1971 candidates. Furthermore, we utilise the collected spectroscopic information from DESI to perform broad-line and narrow-line AGN selections, leading to a total of 4392 AGN candidates in the Q1 field. We investigate and refine the Q1 probabilistic random forest QSO population, selecting a total of 180,666 candidates. Additionally, we perform SED fitting on a subset of sources with available , and by utilizing the derived AGN fraction, we identify a total of 7766 AGN candidates. We discuss purity and completeness of the selections and define two new colour selection criteria (_ and _) to improve on purity, finding 313,714 and 267,513 candidates respectively in the Q1 data. We find a total of 229,779 AGN candidates equivalent to an AGN surface density of 3641 deg for , and a subsample of 30,422 candidates corresponding to an AGN surface density of 482 deg when limiting the depth to . The surface density of AGN recovered from this work is in line with predictions based on the AGN X-ray luminosity functions
Comment les filles apprennent-elles à faire des vidéos ? Conceptions et productions audiovisuelles d’étudiantes en sciences humaines
No full textInternational audienceDepuis le début des années 2000, les possibilités offertes par la vidéo numérique ont connu un développement considérable. Les compétences, surtout acquises dans le cadre privé hors de l’école et de l’université, liées à la production et au partage de vidéo occupent aujourd’hui une place croissante dans la vie sociale et démocratique, qu’il s’agisse de réalisation, d’édition, de montage ou de partage grâce aux plateformes dédiées. Afin d’éclairer les modes d’appropriation de ces compétences, une série d’entretiens, menés avec des étudiantes de Licence en sciences humaines et sociales, est exploitée. La production et le partage de vidéos par ces jeunes adultes semblent répondre à trois objectifs : la mémoire partagée, l’expression d’une créativité et le développement de compétences préprofessionnelles. Ce processus d’apprentissage complexe est largement autodidacte, s’appuyant sur des tutoriels et la reproduction de formats populaires. Il est aussi coconstruit avec les pairs, en tenant compte des commentaires suscités par les vidéos partagées, selon des logiques en partie liées à une construction genrée de la mise en scène de soi sur les réseaux sociaux numériques