We present JWST/MIRI MRS spectroscopy of NGC7319, the largest galaxy in theStephan's Quintet, observed as part of the Early Release Observations (ERO).NGC7319 hosts a type 2 active galactic nucleus (AGN) and a low-power radio jet(L_1.4GHz=3.3x10^22 W Hz^-1) with two asymmetric radio hotspots at 430 pc (N2)and 1.5 kpc (S2) projected distances from the unresolved radio core. The MRSdata suggest that the molecular material in the disk of the galaxy deceleratesthe jet and causes this length asymmetry. We find enhanced emission from warmand hot H_2 (T_w=330+-40 K, T_h=900+-60 K) and ionized gas at the intersectionbetween the jet axis and dust lanes in the disk. This emission is coincidentwith the radio hotspot N2 closest to the core, suggesting that thejet-interstellar medium (ISM) interaction decelerates the jet. Conversely, themid-infrared emission at the more distant hotspot is fainter, more highlyionized, and with lower H_2 excitation, suggesting a more diffuse atomicenvironment where the jet can progress to farther distances. At the N2 radiohotspot, the ionized gas mass (M_ion=(2.4-12)x10^5 Msun) is comparable to thatof the warm H_2, but the former is more turbulent (sigma_ion~300 vs.sigma_H2~150 km/s), so the mechanical energy of the ionized gas is ~1.3-10times higher. From these estimates, we find that only <0.2% of the jet energyremains as mechanical energy in these two ISM phases at N2. We also findextended (r>0.3-1.5 kpc) high-ionization emission ([MgV], [NeVI], and [NeV])close to the radio hotspots. This initial analysis of NGC7319 shows thepotential of MIRI/MRS to investigate the AGN feedback mechanisms due to radiojets and their radiation field in the, often heavily dust-enshrouded, centralregions of galaxies. Understanding these mechanisms is an essential ingredientin the development of cosmological simulations of galaxy evolution.

We present morphologies of galaxies at $z\sim9-17$ resolved by JWST/NIRCam$2-5\mu$m imaging. Our sample consists of $25$ galaxy candidates identified bystringent dropout and photo-$z$ criteria in GLASS, CEERS, SMACS J0723, andStephan's Quintet flanking fields. We perform surface brightness (SB) profilefitting with GALFIT for $6$ bright galaxies with S/N $=10-40$ on an individualbasis and for stacked faint galaxies with secure point-spread functions (PSFs)of the NIRCam real data, carefully evaluating systematics by Monte-Carlosimulations. We compare our results with those of previous JWST studies, andconfirm that effective radii $r_{\rm e}$ of our measurements are consistentwith those of previous measurements at $z\sim 9$. We obtain $r_{\rm e}\simeq200-300$ pc with the exponential-like profiles, S\'ersic indexes of $n\simeq1-1.5$, for galaxies at $z\sim 12-17$, indicating that the relation of $r_{\rme}\propto (1+z)^s$ for $s=-1.19^{+0.16}_{-0.15}$ explains cosmic evolution over$z\sim 0-17$ for $\sim L^*_{z=3}$ galaxies. One bright ($M_{\rm UV}=-21$ mag)galaxy at $z\sim 12$, GL-z12-1, has an extremely compact size with $r_{\rme}=61 \pm 11$ pc that is surely extended over the PSF. Even in the case thatthe GL-z12-1 SB is fit by AGN$+$galaxy composite profiles, the best-fit galaxycomponent is again compact, $r_{\rm e}=78^{+30}_{-12}$ pc that is significantly($>5\sigma$) smaller than the typical $r_{\rm e}$ value at $z\sim 12$.Comparing with numerical simulations, we find that such a compact galaxynaturally forms at $z\gtrsim 10$, and that frequent mergers at the early epochproduce more extended galaxies following the $r_{\rm e}\propto (1+z)^s$relation.

We measure optical colors for the bulges of 312 disk galaxies from theCarnegie-Irvine Galaxy Survey and convert their previously available $R$-bandstructural parameters to stellar mass parameters. We also measure their averagestellar mass surface density in the central 1 kpc ($\Sigma_{1}$). Comparing themass-based Kormendy relation with the original one based on flux, we find thatthe majority of the classifications into classical and pseudo bulges, as wellas their overall statistical properties, remain essentially unchanged. Whilethe bulge type classifications of the Kormendy relation are robust againststellar population effects, the mass-based classification criteria do producebetter agreement between bulge structural properties and their stellarpopulations. Moreover, the mass-based Kormendy relation reveals a population ofultra-dense bulges akin to high-$z$ compact early-type galaxies, which areotherwise hidden in the original Kormendy relation. These bulges are probablyrelics of spheroids assembled in the early Universe, although for some wecannot rule out some contribution from secular growth. We confirm previousstudies that $\Sigma_1$ correlates well with bulge surface densities.