The GALAH survey: tracing the Galactic disk with Open Clusters
  Open clusters are unique tracers of the history of our own Galaxy's disk.
According to our membership analysis based on \textit{Gaia} astrometry, out of
the 226 potential clusters falling in the footprint of GALAH or APOGEE, we find
that 205 have secure members that were observed by at least one of the survey.
Furthermore, members of 134 clusters have high-quality spectroscopic data that
we use to determine their chemical composition. We leverage this information to
study the chemical distribution throughout the Galactic disk of 21 elements,
from C to Eu. The radial metallicity gradient obtained from our analysis is
$-$0.076$\pm$0.009 dex kpc$^{-1}$, which is in agreement with previous works
based on smaller samples. Furthermore, the gradient in the [Fe/H] - guiding
radius (r$_{\rm guid}$) plane is $-$0.073$\pm$0.008 dex kpc$^{-1}$. We show
consistently that open clusters trace the distribution of chemical elements
throughout the Galactic disk differently than field stars. In particular, at
given radius, open clusters show an age-metallicity relation that has less
scatter than field stars. As such scatter is often interpreted as an effect of
radial migration, we suggest that these differences are due to the physical
selection effect imposed by our Galaxy: clusters that would have migrated
significantly also had higher chances to get destroyed. Finally, our results
reveal trends in the [X/Fe]$-$r$_{\rm guid}$$-$age space, which are important
to understand production rates of different elements as a function of space and
time.
