Saved in:
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Preprint |
| Published: |
2026
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2602.02323 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866908806021120000 |
|---|---|
| author | Álvarez-Márquez, J. Colina, L. Crespo-Gomez, A. Kendrew, S. Zavala, J. Marques-Chaves, R. Prieto-Jiménez, C. Abdurro'uf Blanco-Prieto, C. Boogaard, L. A. Castellano, M. Fontana, A. Fudamoto, Y. Fujimoto, S. García-Marín, M. Harikane, Y. Harish, S. Hashimoto, T. Hsiao, T. Iani, E. Inoue, A. K. Langeroodi, D. Lin, R. Melinder, J. Napolitano, L. Ostlin, G. Pérez-González, P. G. Rinaldi, P. Del Pino, B. Rodríguez Santini, P. Sugahara, Y. Treu, T. Varo-O'ferral, A. Wright, G. |
| author_facet | Álvarez-Márquez, J. Colina, L. Crespo-Gomez, A. Kendrew, S. Zavala, J. Marques-Chaves, R. Prieto-Jiménez, C. Abdurro'uf Blanco-Prieto, C. Boogaard, L. A. Castellano, M. Fontana, A. Fudamoto, Y. Fujimoto, S. García-Marín, M. Harikane, Y. Harish, S. Hashimoto, T. Hsiao, T. Iani, E. Inoue, A. K. Langeroodi, D. Lin, R. Melinder, J. Napolitano, L. Ostlin, G. Pérez-González, P. G. Rinaldi, P. Del Pino, B. Rodríguez Santini, P. Sugahara, Y. Treu, T. Varo-O'ferral, A. Wright, G. |
| contents | This work presents the first results of the PRImordial galaxy Survey with MIRI Spectroscopy (PRISMS), a JWST cycle 4 program (PID 8051) aimed at the characterization of a relatively large sample of ten galaxies about 500 Myr after the Big Bang. Here, we present deep (13.9 hours) spectroscopy with the MIRI LRS of the lensed galaxy UNCOVER-26185 at a redshift of z=10.054. It is a faint UV galaxy (UV absolut magnitude of -18.83 mag) previously identified as a X-ray luminous AGN. MIRI LRS detects the H$β$+[OIII]4960,5008 complex and H$α$ emission line with a significance of 10$σ$ and 8$σ$, respectively, as well as the optical continuum emission at rest-frame 0.45 $μ$m and 0.57 $μ$m with a signal-to-noise ratio of 6-7. The UV-to-optical spectral energy distribution, combining continuum and emission lines, is compatible with: (i) a low stellar (A$_V$= 0.2) and nebular (A$_V$=0.0) extinction, (ii) a SFH composed by a young (7 Myr) starburst and an intermediate-age (65 Myr) stellar population, and (iii) a total stellar mass of 1.7$\times$10$^{8}$ M$_{\odot}$. The H$α$-derived star-formation rate is 1.3 M$_{\odot}$ yr$^{-1}$. The low optical emission line ratios locate UNCOVER-26185 as the most metal-poor (Z = 0.04 Z$_{\odot}$), and as outlier with the lowest ionization (logU=-2.5) galaxy identified so far at redshifts above 9. With no evidence of an active galactic nuclei in the rest-frame UV-to-optical spectrum, UNCOVER-26185 has the properties of a metal-poor, main-sequence star-forming galaxy at redshift 10, with ISM and ionization properties very different than those of the already studied UV-bright galaxies at redshifts beyond 10. PRISMS is starting to explore the population of intermediate-UV luminosity galaxies at z=10, covering UV absolute magnitudes in the range of -17.9 to -20.5, fainter than those of UV-bright galaxies studied so far. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2602_02323 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | PRISMS. UNCOVER-26185, a metal-poor SFG at z=10.05 with no evidence for a X-ray-luminous AGN Álvarez-Márquez, J. Colina, L. Crespo-Gomez, A. Kendrew, S. Zavala, J. Marques-Chaves, R. Prieto-Jiménez, C. Abdurro'uf Blanco-Prieto, C. Boogaard, L. A. Castellano, M. Fontana, A. Fudamoto, Y. Fujimoto, S. García-Marín, M. Harikane, Y. Harish, S. Hashimoto, T. Hsiao, T. Iani, E. Inoue, A. K. Langeroodi, D. Lin, R. Melinder, J. Napolitano, L. Ostlin, G. Pérez-González, P. G. Rinaldi, P. Del Pino, B. Rodríguez Santini, P. Sugahara, Y. Treu, T. Varo-O'ferral, A. Wright, G. Astrophysics of Galaxies This work presents the first results of the PRImordial galaxy Survey with MIRI Spectroscopy (PRISMS), a JWST cycle 4 program (PID 8051) aimed at the characterization of a relatively large sample of ten galaxies about 500 Myr after the Big Bang. Here, we present deep (13.9 hours) spectroscopy with the MIRI LRS of the lensed galaxy UNCOVER-26185 at a redshift of z=10.054. It is a faint UV galaxy (UV absolut magnitude of -18.83 mag) previously identified as a X-ray luminous AGN. MIRI LRS detects the H$β$+[OIII]4960,5008 complex and H$α$ emission line with a significance of 10$σ$ and 8$σ$, respectively, as well as the optical continuum emission at rest-frame 0.45 $μ$m and 0.57 $μ$m with a signal-to-noise ratio of 6-7. The UV-to-optical spectral energy distribution, combining continuum and emission lines, is compatible with: (i) a low stellar (A$_V$= 0.2) and nebular (A$_V$=0.0) extinction, (ii) a SFH composed by a young (7 Myr) starburst and an intermediate-age (65 Myr) stellar population, and (iii) a total stellar mass of 1.7$\times$10$^{8}$ M$_{\odot}$. The H$α$-derived star-formation rate is 1.3 M$_{\odot}$ yr$^{-1}$. The low optical emission line ratios locate UNCOVER-26185 as the most metal-poor (Z = 0.04 Z$_{\odot}$), and as outlier with the lowest ionization (logU=-2.5) galaxy identified so far at redshifts above 9. With no evidence of an active galactic nuclei in the rest-frame UV-to-optical spectrum, UNCOVER-26185 has the properties of a metal-poor, main-sequence star-forming galaxy at redshift 10, with ISM and ionization properties very different than those of the already studied UV-bright galaxies at redshifts beyond 10. PRISMS is starting to explore the population of intermediate-UV luminosity galaxies at z=10, covering UV absolute magnitudes in the range of -17.9 to -20.5, fainter than those of UV-bright galaxies studied so far. |
| title | PRISMS. UNCOVER-26185, a metal-poor SFG at z=10.05 with no evidence for a X-ray-luminous AGN |
| topic | Astrophysics of Galaxies |
| url | https://arxiv.org/abs/2602.02323 |