20.500.12556/RUL-166377 Spatially resolved emission lines in galaxies at 4 ≤ z < 10 from the JADES survey evidence for enhanced central star formation We present the first statistical investigation of spatially resolved emission-line properties in a sample of 63 low-mass galaxies at 4 ≤ z < 10 using James Webb Space Telescope (JWST)/NIRSpec Micro Shutter Assembly (MSA) data from the JWST Advanced Deep Extragalactic (JADES) survey, focusing on deep, spatially resolved spectroscopy in the GOODS-S extragalactic field. By performing a stacking of the 2D spectra of the galaxies in our sample, we find an increasing or flat radial trend with increasing radius for [O III]λ5007/Hβ and a decreasing trend for the blended spectral complex (Hη + [Ne III]λ3869 + He Iλ3889 + Hζ)/[O II]λ3727 (3‑4σ significance). These results are still valid when stacking the sample in two redshift bins (i.e. 4 ≤ z < 5.5 and 5.5 ≤ z < 10). The comparison with star-formation photoionisation models suggests that the ionisation parameter increases by ∼0.5 dex with redshift. Under the hypothesis that radial variations in (Hη + [Ne III]λ3869 + He Iλ3889 + Hζ)/[O II]λ3727 are dominated by trends in [Ne III]λ3869/[O II]λ3727, we find a tentative metallicity gradient that increases with radius (i.e. 'inverted') in both redshift bins. Moreover, our analysis reveals strong negative gradients for the equivalent width of Hβ (7σ significance). This trend persists even after removing known active galactic nucleus candidates, and is therefore consistent with a radial gradient primarily in stellar age and secondarily in metallicity. Taken together, our results suggest that the sample is dominated by active central star formation, with possibly inverted metallicity gradients sustained by recent episodes of accretion of pristine gas or strong radial flows. Deeper observations and larger samples are needed to confirm these preliminary results and to validate our interpretation. star formation imaging spectroscopy high red-shift galaxies true false true Angleški jezik Ni določen Članek v reviji 2025-01-09 13:27:21 2025-01-09 13:27:22 2025-11-26 11:41:54 0000-00-00 00:00:00 2024 0 0 17 str. art. A184 Vol. 692 2024 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 524.8 1432-0746 10.1051/0004-6361/202449980 221582595 aa49980-24.pdf aa49980-24.pdf 1 9EC0F5A8CD6F99D9F3CA3940768D0AF6 5b06e975778854bdd8b96d52d441b009eaba11ae7c9d7b5778eb34e01c485b7e 28c8150a-ce85-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=197955 https://www.aanda.org/articles/aa/full_html/2024/12/aa49980-24/aa49980-24.html 0 5bd9915d-ce84-11ef-b232-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=197954 Fakulteta za matematiko in fiziko 0 0 0