We study the spatially resolved physical properties of the Cosmic Snake arc in MACS J1206.2-0847 and the arc in Abell 0521 (A521). These are two strongly lensed galaxies at redshifts $z=1.036$ and $z=1.044$. We used observations of the Hubble Space Telescope (HST) and the Atacama Large Millimeter/submillimeter Array (ALMA). The former gives access to the star formation rate (SFR) and stellar mass ($M_star$), and the latter to the H$_2$ molecular gas mass ($M_{mathrm{mol}}$). HST and ALMA observations have similar angular resolutions of $0.15^{prime prime}-0.2^{prime prime}$, which with the help of strong gravitational lensing enable us to reach spatial resolutions down to $sim 30,mathrm{pc}$ and $sim 100,mathrm{pc}$ in these two galaxies, respectively. These resolutions are close to the resolution of observations of nearby galaxies. We study the radial profiles of SFR, $M_star$, and $M_{mathrm{mol}}$ surface densities of these high-redshift galaxies and compare the corresponding exponential scale lengths with those of local galaxies. We find that the scale lengths in the Cosmic Snake are about $0.5,mathrm{kpc}-1.5,mathrm{kpc}$, and they are 3 to 10 times larger in A521. This is a significant difference knowing that the two galaxies have comparable integrated properties. These high-redshift scale lengths are nevertheless comparable to those of local galaxies, which cover a wide distribution. The particularity of our high-redshift radial profiles is the normalisation of the $M_{mathrm{mol}}$ surface density profiles ($Sigma M_{mathrm{mol}}$), which are offset by up to a factor of 20 with respect to the profiles of $z=0$ counterparts. The SFR surface density profiles are also offset by the same factor as $Sigma M_{mathrm{mol}}$, as expected from the Kennicutt-Schmidt law.
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