Year: 2026
Type: preprint
Abstract: Lensed and Pristine 1 (LAP1) is one of the most promising candidates for the detection of so-called Pop~III stars at $z\sim6.6$. In this work, we present new high-spectral-resolution ($R \sim 2700$) \jwst NIRSpec-IFS observations of the system along with a detailed re-analysis of all archival \jwst and VLT/MUSE data. We confirm the very low metallicity of the system, with $12+\log(\text{O/H})=6.5\text{--}6.8$ (1--2\% Z$_{\odot}$), and its low stellar mass, with $M_{*}= 10^{3\text{--}4}$ \Msun, based on the non-detection in \jwst/NIRCam filter stacks and the \Hbeta luminosity. The high-resolution IFS data allow us to constrain the upper limits on the dynamical masses ($\log_{10}(M_{*}/M_{\odot})$) of the A and B components to $<6.6\text{--}7.6$ and $<5.6\text{--}6.6$, respectively. Based on the metallicity and the high equivalent width of \Halpha (EW $>1200$\,Å), we estimate the possible range of the LAP1 stellar population ages to be $2\text{--}5$~Myr, consistent with the first burst of star formation in a pristine environment. Based on the size ($<10$~pc) and mass of the system, we discuss the nature of LAP1 as representing the formation of the first stellar clusters in a larger undetected galaxy, similar to other low-metallicity Pop~III candidates in the literature.
Source: arXiv (Cornell University)
Authors: Scholtz, J., Maiolino, R., Carniani, S., Vanzella, E., Terlevich, R. J., Übler, H., Perna, M., Arribas, S., Bertola, E., Bergamini, P., Böker, T., Bolamperti, A., Bunker, A., Charlot, S., Curti, M., D'Eugenio, F., Grillo, C., Ivey, L. R., Ji, X., Jones, G. C., Meneghetti, M., Messa, M. M., Pascalau, R., Del Pino, B. Rodríguez, Rosati, P., Rusta, E., Salvadori, S., Terlevich, E., Venturi, G., Zamora, S., Zanella, A.
Institutions: University of Cambridge, Scuola Normale Superiore, Osservatorio di Astrofisica e Scienza dello Spazio, National Institute for Astrophysics, Max Planck Institute for Extraterrestrial Physics, Centro de Astrobiología, Arcetri Astrophysical Observatory, European Space Agency, Max Planck Institute for Astrophysics, University of Oxford, Centre National de la Recherche Scientifique, Institut d'Astrophysique de Paris, Sorbonne Université, University of Milan, University of Ferrara, University of Florence
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: National Aeronautics and Space Administration, Space Telescope Science Institute, UK Research and Innovation, Strong, European Commission, Max-Planck-Gesellschaft, Ministerio de Ciencia e Innovación, Horizon 2020 Framework Programme, Science and Technology Facilities Council, Agencia Estatal de Investigación, European Social Fund
Awards: G103270039, G121809054, G157518229, G1577046871, G1812695587, G1855990336, G192455069, G1969106598, G2005369488, G204809963, G2309174360, G256731684, G2660406951, G3228396264, G3452655474, G3518538256, G3567997761, G3660973570, G430777504, G4915654406, G5195188938, G531848386, G5368796297, G5403136496, G5421974903, G5568641063, G5663025379, G6218905885, G6307073466, G7169023097, G7181133418, G7343478979, G7988610560, G8631195605, G8888022036, G8931419319, G897484643, G99296377
OpenAlex ID: W7214995440