Looking for obscured young star clusters in NCG 1313
  Using recently acquired HST NIR observations (J, Pa$\beta$ and H bands) of
the nearby galaxy NGC1313, we investigate the timescales required by a young
star cluster to emerge from its natal cloud. We search for extincted star
clusters, potentially embedded in their natal cloud as either: 1. compact
sources in regions with high H$\alpha$/Pa$\beta$ extinctions; 2. compact HII
regions that appear as point-like sources in the Pa$\beta$ emission map. The
NUV--optical--NIR photometry of the candidate clusters is used to derive their
ages, masses and extinctions via a least$-\chi^2$ SED broad and narrow--band
fitting process. The 100 clusters in the final samples have masses in the range
$\rm \log_{10}(M/M_\odot)=2.5-3.5$ and moderate extinctions, $\rm
E(B-V)\lesssim1.0$ mag.
  Focusing on the young clusters ($0-6$ Myr) we derive a weak correlation
between extinction and age of the clusters. Almost half of the clusters have
low extinctions, $\rm E(B-V)<0.25$ mag, already at very young ages ($\le3$
Myr), suggesting that dust is quickly removed from clusters. A stronger
correlation is found between the morphology of the nebular emission (compact,
partial or absent, both in H$\alpha$ and Pa$\beta$) and cluster age.
  Relative fractions of clusters associated with a specific nebular morphology
is used to estimate the typical timescales for clearing the natal gas cloud,
resulting between 3 and 5 Myr, $\sim1$ Myr older than what estimated from
NUV--optical--based cluster studies. This difference hints to a bias for
optically--only based studies, which JWST will address in the coming years.
