Euclid Quick Data Release (Q1). A first look at the fraction of bars in massive galaxies at z<1

Astronomy & Astrophysics EDP Sciences (2025)

Authors:

M Huertas-Company, M Walmsley, M Siudek, P Iglesias-Navarro, JH Knapen, S Serjeant, HJ Dickinson, L Fortson, I Garland, T Géron, W Keel, S Kruk, CJ Lintott, K Mantha, K Masters, D O'Ryan, J Popp, H Roberts, C Scarlata, JS Makechemu, B Simmons, RJ Smethurst, A Spindler, M Baes, EM Corsini, H Domínguez Sánchez, E Duran-Camacho, H Fu, J Junais, J Mendez-Abreu, A Nersesian, F Shankar, MN Le, J Vega-Ferrero, L Wang, N Aghanim, B Altieri, A Amara, S Andreon, N Auricchio, C Baccigalupi, M Baldi, A Balestra, S Bardelli, A Basset, P Battaglia, F Bernardeau, A Biviano, A Bonchi, E Branchini, M Brescia, J Brinchmann, S Camera, V Capobianco, C Carbone, J Carretero, S Casas, M Castellano, G Castignani, S Cavuoti, KC Chambers, A Cimatti, C Colodro-Conde, G Congedo, CJ Conselice, L Conversi, Y Copin, F Courbin, HM Courtois, M Cropper, A Da Silva, H Degaudenzi, G De Lucia, AM Di Giorgio, C Dolding, H Dole, F Dubath, CAJ Duncan, X Dupac, S Dusini, A Ealet, S Escoffier, M Fabricius, M Farina, R Farinelli, F Faustini, S Ferriol, F Finelli, S Fotopoulou, M Frailis, S Galeotta, K George, W Gillard, B Gillis, C Giocoli, J Gracia-Carpio, A Grazian, F Grupp, S Gwyn, SVH Haugan, H Hoekstra, W Holmes, IM Hook, F Hormuth, A Hornstrup, P Hudelot, K Jahnke, M Jhabvala, E Keihänen, S Kermiche, B Kubik, K Kuijken, M Kümmel, M Kunz, H Kurki-Suonio, Q Le Boulc'h, AMC Le Brun, D Le Mignant, S Ligori, PB Lilje, V Lindholm, I Lloro, D Maino, E Maiorano, O Mansutti, S Marcin, O Marggraf, M Martinelli, N Martinet, F Marulli, R Massey, HJ McCracken, E Medinaceli, M Melchior, Y Mellier, M Meneghetti, E Merlin, G Meylan, A Mora, M Moresco, L Moscardini, C Neissner, RC Nichol, S-M Niemi, JW Nightingale, C Padilla, S Paltani, F Pasian, K Pedersen, WJ Percival, V Pettorino, S Pires, G Polenta, M Poncet, LA Popa, L Pozzetti, F Raison, A Renzi, J Rhodes, G Riccio, E Romelli, M Roncarelli, R Saglia, Z Sakr, D Sapone, B Sartoris, M Schirmer, P Schneider, M Scodeggio, A Secroun, G Seidel, M Seiffert, S Serrano, P Simon, C Sirignano, G Sirri, L Stanco, J Steinwagner, P Tallada-Crespí, AN Taylor, I Tereno, S Toft, R Toledo-Moreo, F Torradeflot, I Tutusaus, L Valenziano, J Valiviita, T Vassallo, G Verdoes Kleijn, Y Wang, J Weller, A Zacchei, G Zamorani, FM Zerbi, IA Zinchenko, E Zucca, V Allevato, M Ballardini, M Bolzonella, E Bozzo, C Burigana, A Cappi, D Di Ferdinando, JA Escartin Vigo, L Gabarra, J Martín-Fleitas, S Matthew, N Mauri, RB Metcalf, A Pezzotta, M Pöntinen, C Porciani, I Risso, V Scottez, M Sereno, M Tenti, M Viel, M Wiesmann, Y Akrami, IT Andika, S Anselmi, M Archidiacono, F Atrio-Barandela, C Benoist, K Benson, D Bertacca, M Bethermin, L Bisigello, A Blanchard, L Blot, H Böhringer, S Borgani, ML Brown, S Bruton, A Calabro, B Camacho Quevedo, F Caro, CS Carvalho, T Castro, Y Charles, F Cogato, T Contini, AR Cooray, O Cucciati, S Davini, F De Paolis, G Desprez, A Díaz-Sánchez, J Diaz, S Di Domizio, JM Diego, P-A Duc, A Enia, Y Fang, AG Ferrari, A Finoguenov, A Fontana, F Fontanot, A Franco, K Ganga, J García-Bellido, T Gasparetto, V Gautard, E Gaztanaga, F Giacomini, G Gozaliasl, M Guidi, CM Gutierrez, A Hall, WG Hartley, S Hemmati, C Hernández-Monteagudo, H Hildebrandt, J Hjorth, JE Kajava, Y Kang, V Kansal, D Karagiannis, K Kiiveri, C Kirkpatrick, J Le Graet, L Legrand, M Lembo, F Lepori, G Leroy, GF Lesci, J Lesgourgues, L Leuzzi, TI Liaudat, A Loureiro, J Macias-Perez, G Maggio, M Magliocchetti, EA Magnier, F Mannucci, R Maoli, CJAP Martins, L Maurin, M Miluzio, P Monaco, C Moretti, G Morgante, C Murray, K Naidoo, A Navarro-Alsina, S Nesseris, F Passalacqua, K Paterson, L Patrizii, A Pisani, D Potter, S Quai, M Radovich, G Rodighiero, S Sacquegna, M Sahlén, DB Sanders, E Sarpa, J Schaye, A Schneider, M Schultheis, D Sciotti, E Sellentin, LC Smith, K Tanidis, G Testera, R Teyssier, S Tosi, A Troja, M Tucci, C Valieri, A Venhola, D Vergani, G Verza, P Vielzeuf, NA Walton, E Soubrie, D Scott

Abstract:

Stellar bars are key structures in disc galaxies, driving angular momentum redistribution and influencing processes such as bulge growth and star formation. Quantifying the bar fraction as a function of redshift and stellar mass is therefore important for constraining the physical processes that drive disc formation and evolution across the history of the Universe. Leveraging the unprecedented resolution and survey area of the Euclid Q1 data release, combined with the Zoobot deep-learning model trained on citizen science labels, we identified (7711) barred galaxies with (M_* ≳ 10^ M_⊙) in a magnitude-selected sample ((I_E < 20.5)) spanning (63.1 deg ^2). We measured a mean bar fraction of (0.2-0.4), consistent with previous studies. At fixed redshift, massive galaxies exhibit higher bar fractions, while lower-mass systems show a steeper decline with redshift, suggesting earlier disc assembly in massive galaxies. Comparisons with cosmological simulations (e.g. TNG50 Auriga ) reveal a broadly consistent bar fraction, but highlight overpredictions for high-mass systems, pointing to potential over-efficiency in central stellar mass build-up in simulations. A semi-empirical model ( Decode ) in which bar formation is regulated by the gas fraction broadly reproduces the observed bar fractions. These findings demonstrate the transformative potential of Euclid for galaxy morphology studies and underscore the importance of refining theoretical models to better reproduce observed trends. Future work will explore finer mass bins, environmental correlations, and additional morphological indicators.

Evidence for inverse Compton scattering in high-redshift Lyman-break galaxies

(2025)

Authors:

IH Whittam, MJ Jarvis, Eric J Murphy, NJ Adams, RAA Bowler, A Matthews, RG Varadaraj, CL Hale, I Heywood, K Knowles, L Marchetti, N Seymour, F Tabatabaei, AR Taylor, M Vaccari, A Verma

GA-NIFS: an extended [OIII] halo around the sub-Eddington quasar J1342+0928 at z=7.54

(2025)

Authors:

Bartolomeo Trefoloni, Stefano Carniani, Elena Bertola, Giacomo Venturi, Sandra Zamora, Eleonora Parlanti, Santiago Arribas, Andrew Bunker, Stà phane Charlot, Francesco D'Eugenio, Peter Jakobsen, Roberto Maiolino, Michele Perna, Bruno Rodríguez Del Pino, Hannah Übler, Chris J Willott, Torsten Böker, Giovanni Cresci, Isabella Lamperti, Madeline Marshall, Pablo G Pérez-González

PowerBin: Fast Adaptive Data Binning with Centroidal Power Diagrams

ArXiv 2509.06903 (2025)

The Interstellar Medium in I Zw 18 Seen with JWST/MIRI. III. Spatially Resolved Three Ionization State Oxygen Abundance

The Astrophysical Journal American Astronomical Society 990:2 (2025) 111

Authors:

Ryan J Rickards Vaught, Leslie K Hunt, Alessandra Aloisi, Maria Gabriela Navarro, Matilde Mingozzi, Bethan James, Macarena G del Valle-Espinosa, Karin M Sandstrom, Angela Adamo, Francesca Annibali, Daniela Calzetti, BT Draine, Svea Hernandez, Alec S Hirschauer, Margaret Meixner, Dimitra Rigopoulou, Monica Tosi

Abstract:

We present observations of the nearby extremely metal-poor galaxy I Zw 18 using the Keck Cosmic Web Imager (KCWI) and the JWST Mid-InfraRed Instrument (MIRI) Integral Field Spectrographs. From optical and mid-IR oxygen emission lines, we measured direct-method abundances for three ionic states of oxygen, including O3+/H+. In contrast to previous studies of I Zw 18 the high spatial resolution afforded by KCWI and MIRI/MRS revealed chemical inhomogeneities on 60 pc scales in the form of metal-poor pockets and metal-enriched gas. These are located outside I Zw 18’s star-forming complexes having possibly been dispersed beyond these regions via stellar feedback effects. We found that metallicities derived using a single low-ionization density tracer, and Te([O ii]) derived from a temperature relationship commonly used in high-z galaxy studies, exhibited the largest scatter and underestimated the metallicity compared to those derived using multi-ion densities and estimated Te([N ii]). Finally, we compared O3+/H+ abundances from a theoretical ionization correction factor (ICF) against observed values and found that the oxygen ICF underestimates the O3+/H+ abundance by a factor of 2, indicating that either additional ionizing sources are needed or standard stellar population models are unable to produce the requisite ionizing flux.