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Arxiv: Dynamics of GN-z11 Explored by JWST Integral Field Spectroscopy: Gaseous Rotating Disk at z=10.60 Suggestive of Weak Feedback? Published: 4/25/2024 9:24:03 PM Updated: 4/25/2024 9:24:03 PM

Paper abstract: We investigate the dynamics of GN-z11, a luminous galaxy at z=10.60,carefully analyzing the public deep integral field spectroscopy (IFS) datataken with JWST NIRSpec IFU. While the observations of the IFS data originallytargeted a He II clump near GN-z11, we find that CIII]\lambda\lambda1907,1909 emission from ionized gas at GN-z11 is bright andspatially extended significantly beyond the point-spread function (PSF) incontrast with the GN-z11's compact UV-continuum morphology. The spatiallyextended C III] emission of GN-z11 shows a velocity gradient, red- andblue-shifted components in the NE and SW directions, respectively, which cannotbe explained by the variation of [C III]\lambda1907/C III]\lambda1909 lineratios. We perform forward modeling with GalPak^\mathrm{3D}, including theeffects of PSF smearing and line blending, and find that the best-fit model isa nearly edge-on disk with a rotation velocity ofv_\mathrm{rot}=376_{-151}^{+110} km s^{-1}, a velocity dispersion of\sigma_v=113_{-48}^{+24} km s^{-1}, and a ratio ofv_\mathrm{rot}/\sigma_v=3.3_{-1.5}^{+1.7}, indicative of a rotation-dominateddisk at z=10.6. Interestingly, the disk rotation velocity is faster than thecircular velocity at the virial radius, v_\mathrm{c}(r_{200})=205_{-34}^{+28}km s^{-1}, estimated from the stellar mass, suggesting a compact diskproduced under weak feedback such predicted in numerical simulations. In fact,the half-light radius of the C III] emitting gas disk is only 294\pm45 pc,while the one of the stellar UV component is even smaller, 196\pm12 pc. Whilehigher S/N data are necessary for a conclusion, these observational resultswould suggest that GN-z11 has a fast-rotating gaseous disk whose centerpossesses luminous stellar components or AGN providing weak feedback.