PRISMS. GHZ1. A standard tale of galaxy evolution with atypical ionizing conditions at $z=9.878$
Year: 2026
Type: preprint
Abstract: [Abridged] The first operating years of the James Webb Space Telescope (JWST) have revealed a surprising number of $z \gtrsim 10$ UV-bright objects, many of them characterized by their compactness, anomalous chemical abundance patterns and complex ISM physics (e.g. N-enhanced systems). To assess whether these objects are a phase of early galaxy evolution or a peculiar population, it is essential to understand the physics of systems without anomalous abundance patterns in this epoch. We present a detailed analysis of GHZ1 ($z=9.878$), a moderately ($μ= 1.715$) lensed UV-bright ($M_{UV} = -20.07$) galaxy in the Abell2744 field, characterized by an extended size ($R_{e} \sim 410$ pc). These properties, which contrast with the properties of many of the N-enhanced galaxies, make GHZ1 an excellent laboratory to assess what are the major drivers of early galaxy evolution and the origin of the differences. By means of JWST spectroscopic observations from NIRSpec (PRISM-CLEAR configuration) and the MIR/LRS, we analyzed the full UV and optical emission from GHZ1. We used a spectro-photometric SED fitting to characterize the stellar evolution and the emission line spectra to constrain its chemical enrichment. We find that GHZ1 is among the most massive systems at $z\sim 10$ (log(M$_{\star}$ [M$_{\odot}$]) = 9.17$_{-0.26}^{+0.27}$), with a moderate amount of dust attenuation ($A_{V} = 0.21_{-0.12}^{+0.12}$~mag) and ongoing star formation (with a median SFR $= 8.75_{-1.72}^{+1.71}$ M$_{\odot}\cdot$yr$^{-1}$ over the last 10 Myr). Its chemical enrichment patterns (12+log(O/H) = $7.81_{-0.11}^{+0.12}$, log(C/O) = $-0.66_{-0.13}^{+0.13}$, log(N/O)$< -1.04$) are consistent with a standard evolution dominated by primary production from massive stars. We also derive an H$α$/H$β$ Balmer ratio below Case B predictions. We speculate that [...].
Source: arXiv (Cornell University)
Authors: Pérez-Díaz, Borja, Castellano, Marco, Álvarez-Márquez, Javier, Colina, Luis, Napolitano, Lorenzo, Kendrew, Sarah, Gómez, Alejandro Crespo, Carniani, Stefano, Wang, Shouyi, Zou, Fan, Abdurro'uf, Bik, Arjan, Caputi, Karina, Fernández-Aranda, Román, Fontana, Adriano, Fudamoto, Yoshinobu, García-Marín, Macarena, Hamed, Mahmoud, Harikane, Yuichi, Hashimoto, Takuya, Helton, Jakob M., Hsiao, Tiger Y. -Y., Langeroodi, Danial, Lin, Ruqiu, Marques-Chaves, Rui, Östlin, Göran, Pérez-González, Pablo G., Piconcelli, Enrico, Prieto-Jiménez, Carlota, Rinaldi, Pierluigi, Roberts-Borsani, Guido, del Pino, Bruno Rodríguez, Santini, Paola, Treu, Tommaso, Varo-O'Ferrall, Ana, Zavala, Jorge
Institutions: Astronomical Observatory of Rome, National Institute for Astrophysics, Centro de Astrobiología, Space Telescope Science Institute, European Space Agency, Scuola Normale Superiore, Peking University, University of Michigan, Indiana University Bloomington, Indiana University, Stockholm University, University of Groningen, Chiba University, Center for Frontier Science, Chiba University, Institute for Cosmic Ray Research, The University of Tokyo, University of Tsukuba, Tomonaga Center for the History of the Universe, University of Tsukuba, Pennsylvania State University, University of Massachusetts Amherst, University of Geneva, Universidad Complutense de Madrid, The University of Texas at Austin, University College London, University of California, Los Angeles, AlbaNova
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7213243583