Y. FudamotoR. SmitR. A. A. BowlerP. A. OeschR. BouwensM. StefanonH. InamiR. EndsleyV. GonzalezS. SchouwsD. StarkH. S. B. AlgeraM. AravenaL. BarrufetE. da CunhaP. DayalA. FerraraL. GrazianiJ. A. HodgeA. P. S. HygateA. K. InoueT. NanayakkaraA. PallottiniE. PizzatiR. SchneiderL. SommovigoY. SugaharaM. ToppingP. van der WerfM. BetherminP. CassataM. Dessauges-ZavadskyIbar, EduardoEduardoIbarA. L. FaisstS. FujimotoM. GinolfiN. HathiG. C. JonesF. PozziD. Schaerer2025-04-132025-04-132022-08-0110.3847/1538-4357/ac7a472-s2.0-85136091025https://cris-uv-2.scimago.es/handle/123456789/1856WOS:000835049500001Abstract We present the average [C ii ] 158 μ m emission line sizes of UV-bright star-forming galaxies at z ∼ 7. Our results are derived from a stacking analysis of [C ii ] 158 μ m emission lines and dust continua observed by the Atacama Large Millimeter/submillimeter Array (ALMA), taking advantage of the large program Reionization Era Bright Emission Line Survey. We find that the average [C ii ] emission at z ∼ 7 has an effective radius r e of 2.2 ± 0.2 kpc. It is ≳2× larger than the dust continuum and the rest-frame UV emission, in agreement with recently reported measurements for z ≲ 6 galaxies. Additionally, we compared the average [C ii ] size with 4 < z < 6 galaxies observed by the ALMA Large Program to INvestigate [C ii ] at Early times (ALPINE). By analyzing [C ii ] sizes of 4 < z < 6 galaxies in two redshift bins, we find an average [C ii ] size of r e = 2.2 ± 0.2 kpc and r e = 2.5 ± 0.2 kpc for z ∼ 5.5 and z ∼ 4.5 galaxies, respectively. These measurements show that star-forming galaxies, on average, show no evolution in the size of the [C ii ] 158 μ m emitting regions at redshift between z ∼ 7 and z ∼ 4. This finding suggests that the star-forming galaxies could be morphologically dominated by gas over a wide redshift range.enacceso abiertoAstronomy And AstrophysicsSpace And Planetary Sciencearticle