1 Myr ago. Therefore the absence of Class I/0 sources in IC 1795 suggests that star formation was recently and possibly abruptly terminated in that region.

It is important to notice that values for the $R_{\mathrm{II:III}}$ ratio in the map can be high (typically larger than 5), particularly because the Class III sources are more spatially scattered. However, the $R_{\mathrm{II:III}}$ is not the same as the circumstellar disk fraction in the cluster, because we are only measuring against weak disk sources and not the whole population (see also section \[s:analysis:ss:klf\], below).

![image](f8a.eps){width="4.2in"}\
![image](f8b.eps){width="4.2in"}

K band Luminosity Function of Clusters in the W3 Complex \[s:analysis:ss:klf\]
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We obtained the K band luminosity function (KLF) for each of the five principal clusters identified with our GMM analysis using the following procedure:

Each cluster sample is composed by all K-band sources detected within a “3-sigma" radius defined as $R_{3\sigma}=(3.0/\sqrt{8\ln 2})r_{cl}$, where $r_{cl}$ is defined from the GMM analysis as the half-width at half-maximum of the best fit 2-D Gaussian. Defining samples within $R_{3\sigma}$ minimizes effects of cluster overlapping, which could mislead in the estimation of age and age spreads in cluster forming regions [e.g. NGC 1980, @Alves:2012aa].

We obtained an extinction limited sample, 