RT Journal Article T1 A new insight of AGC 198691 (Leoncino) galaxy with MEGARA at the GTC A1 Carrasco, E. A1 García Vargas, M. L. A1 Gil de Paz, Armando A1 Mollá, M. A1 Izazaga Pérez, R. A1 Castillo Morales, África A1 Gómez Álvarez, P. A1 Gallego Maestro, Jesús A1 Iglesias Páramo, J. A1 Cardiel López, Nicolás A1 Pascual Ramírez, Sergio A1 Pérez Calpena, A. AB We describe the observations of the low metallicity nearby galaxy AGC 198691 (Leoncino Dwarf) obtained with the Integral Field Unit of the instrument MEGARA at the Gran Telescopio Canarias. The observations cover the wavelength ranges 4304-5198 Aand 6098-7306 Awith a resolving power R approximate to 6000. We present 2D maps of the ionized gas, deriving the extension of the H II region and gas kinematics from the observed emission lines. We have not found any evidence of recent gas infall or loss of metals by means of outflows. This result is supported by the closed-box model predictions, consistent with the oxygen abundance found by other authors in this galaxy and points towards Leoncino being a genuine XMD galaxy. We present for the first time spatially resolved spectroscopy allowing the detailed study of a star-forming region. We use POPSTAR + CLOUDY models to simulate the emission-line spectrum. We find that the central emission-line spectrum can be explained by a single young ionizing cluster with an age of approximate to 3.5 +/- 0.5 Myr and a stellar mass of approximate to 2 x10(3) M-circle dot. However, the radial profiles of [O III].5007Aand the Balmer lines in emission demand photoionization by clusters of different ages between 3.5 and 6.5 Myr that might respond either to the evolution of a single cluster evolving along the cooling time of the nebula (approximate to 3 Myr at the metallicity of Leoncino, Z approximate to 0.0004) or to mass segregation of the cluster, being both scenarios consistent with the observed equivalent widths of the Balmer lines. PB Wiley SN 0035-8711 YR 2022 FD 2022-02 LK https://hdl.handle.net/20.500.14352/72136 UL https://hdl.handle.net/20.500.14352/72136 LA eng NO © 2021 The Author(s). Published by Oxford University Press on behalf of Royal Astronomical Society. The authors are grateful to the referee, Alec S. Hirschauer, for his constructive comments and suggestions. This work is based on observations made with the Gran Telescopio Canarias (GTC), installed in the Spanish Observatorio del Roque de los Muchachos, on the island of La Palma. The work is based on data obtained with the MEGARA instrument, funded by European Regional Development Funds (ERDF), through the Programa Operativo Canarias FEDER 2014-2020. The authors thank the support given by Dr. Antonio Cabrera and Dr. Daniel Reverte, GTC Operations Group staff, during the preparation and execution of the observations at the GTC. This work has been supported by DGICYT grant RTI2018-096188-B-I00, which is partly funded by the European Regional Development Fund (ERDF). Jorge Iglesias acknowledges financial support from the following projects: Estallidos6 AYA2016-79724-C4 (Spanish Ministerio de Economía y Competitividad), Estallidos7 PID2019-107408GB-C44 (Spanish Ministerio de Ciencia e Innovación), grant P18-FR-2664 (Junta de Andalucía), and grant SEV-2017-0709 'Centro de Excelencia Severo Ochoa Program' (Spanish Science Ministry). This research is based on observations made with the NASA/ESA Hubble Space Telescope obtained from the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with program 15243. Based on observations made with the NASA/ESA Hubble Space Telescope, obtained from the data archive at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc. under NASA contract NAS 5-26555. NO Ministerio de Ciencia e Innovación (MICINN)/FEDER NO Ministerio de Economía y Competitividad (MINECO) NO Ministerio de Ciencia e Innovación (MICINN) NO Centro de Excelencia Severo Ochoa NO Junta de Andalucía NO NASA National Aeronautics & Space Administration (NASA) DS Docta Complutense RD 8 may 2024