Resolved Kennicutt-Schmidt law in two strongly lensed star-forming galaxies at redshift 1. (arXiv:2307.07551v1 [astro-ph.GA])
<a href="http://arxiv.org/find/astro-ph/1/au:+Nagy_D/0/1/0/all/0/1">David Nagy</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Dessauges_Zavadsky_M/0/1/0/all/0/1">Miroslava Dessauges-Zavadsky</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Messa_M/0/1/0/all/0/1">Matteo Messa</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Richard_J/0/1/0/all/0/1">Johan Richard</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Sun_J/0/1/0/all/0/1">Jiayi Sun</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Combes_F/0/1/0/all/0/1">Fran&#xe7;oise Combes</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Eyholzer_Y/0/1/0/all/0/1">Yannick Eyholzer</a>

We study the star formation rate (SFR) versus molecular gas mass
($M_mathrm{mol}$) scaling relation from hundreds to thousands parsec scales in
two strongly lensed galaxies at redshift $zsim 1$, the Cosmic Snake and A521.
We trace SFR using extinction-corrected rest-frame UV observations with the
Hubble Space Telescope (HST), and $M_mathrm{mol}$ using detections of the
CO(4–3) line with the Atacama Large Millimetre/submillimetre Array (ALMA). The
similar angular resolutions of our HST and ALMA observations of $0.15-0.2,”$
combined with magnifications reaching $mu>20$ enable us to resolve structures
in the galaxies of sizes lower than $100,mathrm{pc}$. These resolutions are
close to those of nearby galaxies studies. This allows us to investigate for
the first time the Kennicutt-Schmidt (KS) law (SFR-$M_mathrm{mol}$ surface
densities) at different spatial scales, from galactic scales to $sim
100,mathrm{pc}$ scales, in galaxies at $zsim 1$. At integrated scales we
find that both galaxies satisfy the KS law defined by galaxies at redshifts
between 1 and 2.5. We test the resolved KS (rKS) law in cells of sizes down to
$200,mathrm{pc}$ in the two galaxies. We observe that this relationship
generally holds in these $zsim 1$ galaxies although its scatter increases
significantly with decreasing spatial scales. We check the scale dependence of
the spatial correlation between the surface densities of SFR and
$M_mathrm{mol}$ by focussing on apertures centred on individual star-forming
regions and molecular clouds. We conclude that star-forming regions and
molecular clouds become spatially de-correlated at $lesssim 1,mathrm{kpc}$
in the Cosmic Snake, whereas they appear de-correlated at all spatial scales
(from $400,mathrm{pc}$ to $6,mathrm{kpc}$) in A521.

We study the star formation rate (SFR) versus molecular gas mass
($M_mathrm{mol}$) scaling relation from hundreds to thousands parsec scales in
two strongly lensed galaxies at redshift $zsim 1$, the Cosmic Snake and A521.
We trace SFR using extinction-corrected rest-frame UV observations with the
Hubble Space Telescope (HST), and $M_mathrm{mol}$ using detections of the
CO(4–3) line with the Atacama Large Millimetre/submillimetre Array (ALMA). The
similar angular resolutions of our HST and ALMA observations of $0.15-0.2,”$
combined with magnifications reaching $mu>20$ enable us to resolve structures
in the galaxies of sizes lower than $100,mathrm{pc}$. These resolutions are
close to those of nearby galaxies studies. This allows us to investigate for
the first time the Kennicutt-Schmidt (KS) law (SFR-$M_mathrm{mol}$ surface
densities) at different spatial scales, from galactic scales to $sim
100,mathrm{pc}$ scales, in galaxies at $zsim 1$. At integrated scales we
find that both galaxies satisfy the KS law defined by galaxies at redshifts
between 1 and 2.5. We test the resolved KS (rKS) law in cells of sizes down to
$200,mathrm{pc}$ in the two galaxies. We observe that this relationship
generally holds in these $zsim 1$ galaxies although its scatter increases
significantly with decreasing spatial scales. We check the scale dependence of
the spatial correlation between the surface densities of SFR and
$M_mathrm{mol}$ by focussing on apertures centred on individual star-forming
regions and molecular clouds. We conclude that star-forming regions and
molecular clouds become spatially de-correlated at $lesssim 1,mathrm{kpc}$
in the Cosmic Snake, whereas they appear de-correlated at all spatial scales
(from $400,mathrm{pc}$ to $6,mathrm{kpc}$) in A521.

http://arxiv.org/icons/sfx.gif