with the age of DR15-C.

![image](f7.pdf){width="7.0in"}

### YSO population ages from the K-band Luminosity Function  {#analysis:sfh:clusterages}

One of the goals of this study is to reconstruct the history of star formation in the region, by estimating the mean age and age spread of a set of the clusters and groups we identified from the `gather` maps. For this purpose, we constructed the K-band luminosity functions (KLF) of the groups and clusters, and compared them to the KLF of artificial pre-main sequence populations with different age ranges and age spreads. These artificial KLFs were constructed using the pre-main sequence model interpolation code of @Muench:2000aa. Another example of this method applied to a young cluster population can be found in @Roman:2015aa

We selected the samples for DR15-C,DR15-W, DR15-SW and DR15-SE for this analysis. The samples were defined as circular areas that covered the four overdensities. The radii of the circles was chosen as 0.03 deg for DR15-W,SW and SE, and as 0.0225 for DR15-C. The KLF was constructed by limiting the samples by extinction in the following manner: we restricted the sample to those sources that a) fall above an extinction vector corresponding $A_V$=20 mag that reaches the sensitivity limit in a 