Tracing AGN–galaxy co-evolution with UV line-selected obscured AGN

Monthly Notices of the Royal Astronomical Society Oxford University Press 545:2 (2025) staf2076

Authors:

Luigi Barchiesi, L Marchetti, M Vaccari, C Vignali, F Pozzi, I Prandoni, R Gilli, M Mignoli, J Afonso, V Singh, CL Hale, I Heywood, MJ Jarvis, IH Whittam

Abstract:

Understanding black hole–galaxy co-evolution and the role of active galactic nucleus (AGN) feedback requires complete AGN samples, including heavily obscured systems. Such sources are key to constraining the black hole accretion rate density over cosmic time, yet they are challenging to identify and characterize across most wavelengths. In this work, we present the first ultraviolet (UV) line-selected ([Ne v] Å and C iv Å) sample of obscured AGN with full X-ray-to-radio coverage, assembled by combining data from the Chandra COSMOS Legacy survey, the COSMOS2020 UV–NIR catalogue, mid- and far-IR photometry from XID+, and radio observations from the Very Large Array and MeerKAT International GHz Tiered Extragalactic Exploration Survey (MIGHTEE) surveys. Using cigale to perform spectral energy distribution (SED) fitting, we analyse 184 obscured AGNs at and , enabling detailed measurements of AGN and host-galaxy properties, and direct comparison with simba hydrodynamical simulations. We find that X-ray and radio data are essential for accurate SED fits, with the radio band proving critical when X-ray detections are missing or in cases of poor IR coverage. Comparisons with matched non-active galaxies and simulations suggest that the [Ne v]-selected sources are in a pre-quenching stage, while the C iv-selected ones are likely quenched by AGN activity. Our results indicate that [Ne v] and C iv selections target galaxies in a transient phase of their co-evolution, characterized by intense, obscured accretion, and pave the way for future extensions with upcoming large area high-z spectroscopic surveys.

The Four‐Pillar Intersectionality Framework: Reframing Sustainable Entrepreneurship as a Transdisciplinary Domain

Business Strategy and the Environment Wiley (2025)

Authors:

Giusy Sica, Chiara Spiniello, Alessandra Micozzi, Maria Palazzo

Abstract:

This study offers a comprehensive bibliometric and text‐mining overview of two decades of sustainability‐oriented entrepreneurship research. Drawing on 7563 peer‐reviewed articles from the Web of Science Core Collection, we map the field's evolution, thematic structure, and disciplinary convergence, identifying influential authors, networks, and journals. Using rule‐based classification and unsupervised learning, we categorize contributions within a four‐pillar framework encompassing environmental, social, economic, and cultural dimensions and examine their prevalence, overlap, and temporal trends. The results reveal a pronounced shift toward transdisciplinarity: 77% of articles engage with at least three pillars, and 34.5% address all four simultaneously. Building directly on this empirical evidence, we propose the Four‐Pillar Intersectionality Framework (F‐PIF), which reconceptualizes sustainable entrepreneurship as a transdisciplinary knowledge domain shaped by interdependent sustainability logics. The F‐PIF is therefore both derived from and supported by the bibliometric findings, providing an empirically grounded conceptual model that advances theoretical understanding and offers practical guidance for scholars and practitioners navigating entrepreneurship in the age of sustainability.

JADES: Low Surface Brightness Galaxies at 0.4 < z < 0.8 in GOODS-S

(2025)

Authors:

Tristen Shields, Marcia Rieke, Kevin Hainline, Jakob M Helton, Andrew J Bunker, Courtney Carreira, Emma Curtis-Lake, Daniel J Eisenstein, Benjamin D Johnson, Pierluigi Rinaldi, Brant Robertson, Christina C Williams, Christopher NA Willmer, Yang Sun

PAH Marks the Spot: Digging for Buried Clusters in Nearby Star-forming Galaxies

The Astronomical Journal IOP Publishing 170:6 (2025) 340

Authors:

Gabrielle B Graham, Daniel A Dale, Chase L Smith, Elisabeth Brann, Kaycee D Conder, Samuel Crowe, Sumitra Dhileepkumar, Nicole A Imming, Emilio Mendez, Zachary Pleska, Kelsey Sako, Amirnezam Amiri, Ashley T Barnes, Médéric Boquien, Rupali Chandar, Ryan Chown, Oleg Y Gnedin, Kathryn Grasha, Stephen Hannon, Hamid Hassani, Rémy Indebetouw, Hwihyun Kim, Jaeyeon Kim, Hannah Koziol, Thomas G Williams

Abstract:

The joint capabilities of the Hubble Space Telescope (HST) and JWST allow for an unparalleled look at the early lives of star clusters at near- and mid-infrared wavelengths. We present here a multiband analysis of embedded young stellar clusters in 11 nearby, star-forming galaxies, using the PHANGS-JWST and PHANGS-HST data sets. We use the Zooniverse citizen science platform to conduct an initial by-eye search for embedded clusters in near-UV/optical/near-infrared images that trace stellar continuum emission, the Paschenα and Hα recombination lines, and the 3.3 ÎŒm polycyclic aromatic hydrocarbon feature and its underlying continuum. With this approach, we identify 292 embedded cluster candidates for which we characterize their ages, masses, and levels of line-of-sight extinction by comparing the photometric data to predictions from stellar population models. The embedded cluster candidates have a median age of 4.5 Myr and an average line-of-sight extinction 〈AV〉 = 6.0 mag. We determine lower limits on source stellar masses, resulting in a median stellar mass of 103 M⊙. We use this sample of embedded cluster candidates to train multiple convolutional neural network models to carry out deep transfer learning-based searches for embedded clusters. With the aim of optimizing models for future catalog production, we compare results for four variations of training data using two neural networks. Confusion matrices for all eight model configurations, as well as inter-model identification trends, are presented. With refinement of the training sample, we determine that optimized models could serve as a pathway for future embedded cluster identification beyond our 11 galaxy sample.

The GECKOS survey: the formation history of a barred galaxy via structural decomposition and spatially resolved spectroscopy

Astronomy & Astrophysics EDP Sciences 705 (2025) A1

Authors:

A Fraser-McKelvie, Da Gadotti, F Fragkoudi, C de SĂĄ-Freitas, M Martig, Martin Bureau, T Davis, E Emsellem, R Elliott, D Fisher, M Hayden, J van de Sande, Ab Watts.

Abstract:

Disentangling the (co-)evolution of individual galaxy structural components remains a difficult task, owing to the inability to cleanly isolate light from spatially overlapping components. In this pilot study of PGC 044931, observed as part of the GECKOS survey, we utilise a VIRCAM H-band image to decompose the galaxy into five photometric components, three of which dominate by contributing > 50% of light in specific regions: a main disc, a boxy/peanut bulge, and a nuclear disc. When the photometric decompositions are mapped onto MUSE observations, we find remarkably good separation in stellar kinematic space. All three structures occupy unique locations in the parameter space of the ratio of the light-weighted stellar line-of-sight mean velocity and velocity dispersion (V⋆/σ⋆), and the high-order stellar skew (h3). These clear and distinct kinematic behaviours allow us to make inferences about the formation histories of the individual components from observations of the mean stellar ages and metallicities of the three components. A clear story emerges: the main disc built over a sustained and extended star formation phase, possibly partly fuelled by gas from a lowmetallicity reservoir. Early on, that disc formed a bar that buckled and subsequently formed a nuclear disc in multiple and enriched star-formation episodes. This result is an example of how careful photometric decompositions, combined with spatially well-resolved stellar kinematic information, can help separate out age-metallicity relations of different components and therefore disentangle the formation history of a galaxy. The results of this pilot study can be extended to a differential study of all GECKOS survey galaxies to assert the true diversity of Milky Way-like galaxies.