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Les monuments funéraires du Bronze ancien de Roque del Die à Capendu (Aude)
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« Speculum themed issue : "Race, Race-Thinking, and Identity in the Global Middle Ages" »
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Nora, ville islamique de l’Éthiopie médiévale (fin du XIIIe-début du XVIe siècle) : les fouilles de 2008
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"Beads-on-a-string" Star Formation Tied to One of the Most Powerful Active Galactic Nucleus Outbursts Observed in a Cool-core Galaxy Cluster
No full textInternational audienceWith two central galaxies engaged in a major merger and a remarkable chain of 19 young stellar superclusters wound around them in projection, the galaxy cluster SDSS J1531+3414 (z = 0.335) offers an excellent laboratory to study the interplay between mergers, active galactic nucleus (AGN) feedback, and star formation. New Chandra X-ray imaging reveals rapidly cooling hot (T ∼ 106 K) intracluster gas, with two "wings" forming a concave density discontinuity near the edge of the cool core. LOFAR 144 MHz observations uncover diffuse radio emission strikingly aligned with the "wings," suggesting that the "wings" are actually the opening to a giant X-ray supercavity. The steep radio emission is likely an ancient relic of one of the most energetic AGN outbursts observed, with 4pV > 1061 erg. To the north of the supercavity, GMOS detects warm (T ∼ 104 K) ionized gas that enshrouds the stellar superclusters but is redshifted up to +800 km s‑1 with respect to the southern central galaxy. The Atacama Large Millimeter/submillimeter Array detects a similarly redshifted ∼1010 M ⊙ reservoir of cold (T ∼ 102 K) molecular gas, but it is offset from the young stars by ∼1–3 kpc. We propose that the multiphase gas originated from low-entropy gas entrained by the X-ray supercavity, attribute the offset between the young stars and the molecular gas to turbulent intracluster gas motions, and suggest that tidal interactions stimulated the "beads-on-a-string" star formation morphology
A spectacular galactic scale magnetohydrodynamic powered wind in ESO 320-G030
No full textInternational audienceHow galaxies regulate nuclear growth through gas accretion by supermassive black holes (SMBHs) is one of the most fundamental questions in galaxy evolution. One potential way to regulate nuclear growth is through a galactic wind that removes gas from the nucleus. It is unclear whether galactic winds are powered by jets, mechanical winds, radiation, or via magnetohydrodynamic (MHD) processes. Compact obscured nuclei represent a significant phase of galactic nuclear growth. These galaxies hide growing SMBHs or unusual starbursts in their very opaque, extremely compact (r < 100 pc) centres. They are found in approximately 30% of the luminous and ultra-luminous infrared galaxy population. Here, we present high-resolution ALMA observations (∼30 mas, ∼5 pc) of ground-state and vibrationally excited HCN towards ESO 320-G030 (IRAS 11506-3851). ESO 320-G030 is an isolated luminous infrared galaxy known to host a compact obscured nucleus and a kiloparsec-scale molecular wind. Our analysis of these high-resolution observations excludes the possibility of a starburst-driven wind, a mechanically or energy driven active galactic nucleus wind, and exposes a molecular MDH wind. These results imply that the nuclear evolution of galaxies and the growth of SMBHs are similar to the growth of hot cores or protostars where gravitational collapse of the nuclear torus drives a MHD wind. These results mean galaxies are capable, in part, of regulating the evolution of their nuclei without feedback
Prendre ses dieux avec soi. Contribution à l'étude du polythéisme dans le cadre de la colonisation parienne et milésienne
No full textDuring the migratory movement of the Archaic period, commonly referred to as “Greek colonization”, numerous communities moved to distant territories to establish new political and religious entities. The aim of this thesis is to study the way in which Greek polytheism related to these ventures through two complementary dossiers: Paros and its colony Thasos in the northern Aegean, and Miletus and its settlements in Propontides and the Black Sea. The first stage consists in gathering documentation on the course of Parian and Miletian colonization, in order to question the feasibility of a study devoted to the constitution of a “local pantheon” and to cult transfers between a metropolis and its colony. Moving beyond an event-based perspective, we will attempt to establish the contours that the population movements of the Archaic period took on in the Greek imagination, before considering the involvement of deities such as Apollo and Artemis in later discourses and practices. Examining the ways in which supra-human powers are summoned in a variety of situations will help us to understand the stakes and perceptions of these overseas ventures, as well as the role attributed to the gods in the founding of a city.Durant le mouvement migratoire de l’époque archaïque appelé communément « colonisation grecque », de nombreuses communautés se sont déplacées vers des territoires lointains pour y établir de nouvelles entités politiques et religieuses. L’objectif de cette thèse est d’étudier la manière dont le polythéisme grec s’articule à ces entreprises par le biais de deux dossiers complémentaires : Paros et sa colonie Thasos dans le nord de l’Égée, Milet et ses implantations en Propontide et en mer Noire. La première étape consiste à rassembler la documentation relative au déroulement de la colonisation parienne et milésienne, afin de questionner la faisabilité d’une étude consacrée à la constitution d’un « panthéon local » et aux transferts cultuels entre une métropole et sa colonie. Dépassant ensuite la perspective événementielle, nous tenterons d’établir les contours que les mouvements de population de l’époque archaïque revêtent dans l’imaginaire grec, avant d’envisager l’implication de divinités comme Apollon et Artémis au sein des discours et des pratiques ultérieurs. Examiner selon quelles modalités les puissances supra-humaines sont convoquées dans une pluralité de situations permettra d’appréhender les enjeux et la perception de ces entreprises d’outre-mer, et de mieux comprendre le rôle attribué aux dieux dans le cadre de la fondation d’une cité
Entanglement Dynamics in Monitored Systems and the Role of Quantum Jumps
No full textInternational audienceMonitored quantum many-body systems display a rich pattern of entanglement dynamics, which is unique to this nonunitary setting. This work studies the effect of quantum jumps on the entanglement dynamics beyond the no-click limit corresponding to a deterministic non-Hermitian evolution. To this aim, we introduce a new tool that looks at the statistics of entanglement-entropy gain and loss after and in between quantum jumps. This insight allows us to build a simple stochastic model of a random walk with partial resetting, which reproduces the entanglement dynamics, and to dissect the mutual role of jumps and non-Hermitian evolution on the entanglement scaling. We apply these ideas to the study of measurement-induced transitions in monitored fermions. We demonstrate that significant deviations from the no-click limit arise whenever quantum jumps strongly renormalize the non-Hermitian dynamics, as in the case of models with U ( 1 ) symmetry at weak monitoring. On the other hand, we show that the weak-monitoring phase of the Ising chain leads to a robust subvolume logarithmic phase due to weakly renormalized non-Hermitian dynamics. Published by the American Physical Society 202
