Examinando por Autor "Izumi, Takuma"

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Acceso Abierto
GATOS: Distinct Feedback Modes in AGN Central Regions Revealed by Spatially Resolved JWST Spectroscopy
(IOP Publishing, 2026-08-20) Zhang, Lulu; Packham, Christopher; Hicks, Erin K. S.; García Bernete, Ismael; Alonso-Herrero, Almudena; Davies, R. I.; Ward, Martin J.; Delaney, Daniel; Izumi, Takuma; Rigopoulou, Dimitra; Ramos Almeida, Cristina; González Martín, Omaira; Riffel, Rogemar A.; Ricci, Claudio; Villar Martín, Montserrat; Combes, Francoise; Pereira Santaella, Miguel; Hönig, Sebastian; Bunker, Andrew; Boorman, Peter; Bellocchi, Enrica; Levenson, Nancy A.; García-Burillo, Santiago; Donnan, Fergus; Audibert, Anelise; Fuller, Lindsay; Díaz Santos, Tanio; Rosario, David J.; Fundação de Amparo à Pesquisa do Estado do Rio Grande do Sul (FAPERGS); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Agencia Estatal de Investigación (AEI); National Aeronautics and Space Administration (NASA); Space Telescope Science Institute (STScI); Comunidad de Madrid; European Commission (EC); Universidad Nacional Autónoma de México (UNAM)
This Letter presents JWST MIRI/Medium-Resolution Spectrometer (MRS) observations of the central r ≈ 40–240 pc regions of five active galactic nuclei (AGN) spanning a wide range of luminosities (log Lbol/erg s−1 ≈ 39.8–43.8). Combining multiphase diagnostics from polycyclic aromatic hydrocarbons (PAHs), molecular hydrogen (H2), and ionized gas at spatial scales of ∼4–24 pc, this study presents a spatially resolved investigation into the effects of the two distinct AGN feedback modes—radiative and kinetic—on the surrounding medium. The results indicate that these two feedback modes, associated with AGN irradiation and shock processing, respectively, collectively drive the relative suppression of PAH emission in the nuclear regions of the targets studied here. Moreover, the coexistence of these two AGN feedback modes, especially the shock processing associated with either jets or outflows, in the central regions of AGN naturally explains both the bimodal distribution of PAH band ratios observed in the targets studied here and the seemingly disparate results reported in the literature. Although based on a limited sample, these findings provide new insights into calibrating star formation rates from PAH emission in AGN and, more importantly, lay the groundwork for a practical framework to diagnose and quantify AGN feedback in the JWST era.
Acceso Abierto
Molecular gas stratification and disturbed kinematics in the Seyfert galaxy MCG-05-23-16 revealed by JWST and ALMA
(EDP Sciences, 2025-01-15) Esparza Arredondo, Donaji; Ramos Almeida, Cristina; Audibert, Anelise; Pereira Santaella, Miguel; García Bernete, Ismael; García-Burillo, Santiago; Shimizu, Thomas Taro; Davies, Richard; Hermosa Muñoz, Laura; Alonso-Herrero, Almudena; Combes, Francoise; Speranza, G.; Zhang, Lulu; Campbell, Stephanie; Bellocchi, Enrica; Bunker, Andrew; Díaz Santos, T.; García Lorenzo, Begoña; González Martín, Omaira; Hicks, Erin K. S.; Labiano, Alvaro; Levenson, Nancy A.; Ricci, Claudio; Rosario, D.; Hönig, Sebastian; Packham, Christopher; Stalevski, Marko ; Fuller, Lindsay; Izumi, Takuma; López Rodríguez, Enrique, E.; Rigopoulou, Dimitra; Rouan, Daniel; Ward, Martin J.; European Research Council (ERC); Comunidad de Madrid; Agencia Estatal de Investigación (España); Fondo Nacional de Desarrollo Científico y Tecnológico (FONDECYT); Space Telescope Science Institute (US); Hellenic Foundation for Research and Innovation; Agencia Nacional de Investigación y Desarrollo (Chile)
Understanding the processes that drive the morphology and kinematics of molecular gas in galaxies is crucial for comprehending star formation and, ultimately, galaxy evolution. Using data from the Galactic Activity, Torus and Outflow Survey (GATOS) obtained with the James Webb Space Telescope (JWST) and the archival data from the Atacama Large Millimeter/submillimeter Array (ALMA), we study the behavior of the warm molecular gas at temperatures of hundreds of Kelvin and the cold molecular gas at tens of Kelvin in the galaxy MCG−05−23−16, which hosts an active galactic nucleus (AGN). Hubble Space Telescope (HST) images of this spheroidal galaxy, classified in the optical as S0, show a dust lane resembling a nuclear spiral and a surrounding ring. These features are also detected in CO(2−1) and H2, and their morphologies and kinematics are consistent with rotation plus local inward gas motions along the kinematic minor axis in the presence of a nuclear bar. The H2 transitions 0-0 S(3), 0-0 S(4), and 0-0 S(5), which trace warmer and more excited gas, show more disrupted kinematics than 0-0 S(1) and 0-0 S(2), including clumps of high velocity dispersion (of up to ∼160 km s−1), in regions devoid of CO(2−1). The kinematics of one of these clumps, located ∼350 pc westward of the nucleus, are consistent with outflowing gas, possibly driven by localized star formation traced by polycyclic aromatic hydrocarbon emission at 11.3 μm. Overall, we observe a stratification of the molecular gas, with the colder gas located in the nuclear spiral, ring, and connecting arms, and most of the warmer gas with a higher velocity dispersion filling the inter-arm space. The compact jet, approximately 200 pc in size, detected with Very Large Array (VLA) observations, does not appear to significantly affect the distribution and kinematics of the molecular gas, possibly due to its limited intersection with the molecular gas disk.