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Arxiv: Dynamics of a Galaxy at z > 10 Explored by JWST Integral Field Spectroscopy: Hints of Rotating Disk Suggesting Weak Feedback Published: 4/25/2024 9:24:03 PM Updated: 9/20/2024 1:59:01 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\lambda1907,1909emission from ionized gas at GN-z11 is bright and spatially extendedsignificantly beyond the point-spread function (PSF). The spatially extendedCIII emission of GN-z11 shows a velocity gradient, red- and blue-shiftedcomponents in the north and south directions, respectively, which cannot beexplained by the variation of [CIII]\lambda1907/CIII]\lambda1909 lineratios. Assuming the velocity gradient is produced by disk rotation, we performforward modeling with GalPak^{3D}, including the effects of PSF smearing andline blending, and obtain a rotation velocity of v_{rot}=257^{+138}_{-117} kms^{-1}, a velocity dispersion of \sigma_v=91^{+18}_{-32} km s^{-1}, and aratio of v_{rot}/\sigma_v=2.83^{+1.82}_{-1.41}. The v_{rot}/\sigma_v valuewould suggest a rotation-dominated disk existing at z>10 albeit with thelarge uncertainties. The rotation velocity agrees with those of numericalsimulations predicting a rotating disk formed in the early universe under thecondition of mass compaction and weak feedback. While the velocity gradient isconsistent with the rotating disk solution, we recognize that galactic outflowscan also explain the velocity gradient as well as the extended morphology andthe high velocity dispersion found in the outskirt. Higher S/N and resolutiondata are necessary to conclude the physical origin of the velocity gradient inGN-z11.