  We study the H$\alpha$ equivalent width, EW(H$\alpha$), maps of 19 galaxies
at $0.6 < z < 2.2$ in the Hubble Ultra Deep Field (HUDF) derived from NIRISS
slitless spectroscopy as part of the Next Generation Deep Extragalactic
Exploratory Public (NGDEEP) Survey. Our galaxies mostly lie on the
star-formation main sequence with a stellar mass range of $\mathrm{10^9 -
10^{11} M_\odot}$, and are therefore characteristic of "typical" star-forming
galaxies at these redshifts. Leveraging deep HST and JWST broad-band images,
spanning 0.4-4 $\mu$m, we perform spatially-resolved fitting of the spectral
energy distributions (SEDs) for these galaxies and construct specific star
formation rate (sSFR) and stellar-mass-weighted age maps. We compare these to
the EW(H$\alpha$) maps with a spatial resolution of $\sim$1 kpc. The
pixel-to-pixel EW(H$\alpha$) increases with increasing sSFR and with decreasing
age, with the average trend slightly different from the relations derived from
integrated fluxes of galaxies from the literature. Quantifying the radial
profiles of EW(H$\alpha$), sSFR, and age, the majority (84%) of galaxies show
positive EW(H$\alpha$) gradients, positive sSFR gradients, and negative age
gradients, in line with the the inside-out quenching scenario. A few galaxies
(16%) show inverse (and flat) trends possibly due to merging or starbursts.
Comparing the distributions of EW(H$\alpha$) and sSFR to the star formation
history models as a function of galactocentric radius, the central region of
galaxies (e.g., their bulges) have experienced, at least one, rapid
star-formation episodes, which leads to the formation of bulge, while their
outer regions (e.g., disks) grow in a more steady-state. These results
demonstrate the ability to study resolved star formation in distant galaxies
with JWST NIRISS.

Astrophysics of Galaxies