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We analyze the X-ray spectra of the $\sim$8000 sources detected in the CygnusOB2 Chandra Legacy Survey (Drake et al., this issue), with the goals ofcharacterizing the coronal plasma of the young low-mass stars in the region andestimating their intrinsic X-ray luminosities. We adopt two differentstrategies for X-ray sources for which more or less than 20 photons weredetected. For the brighter sample we fit the spectra with absorbed isothermalmodels. In order to limit uncertainties, for most of the fainter Cygnus OB2members in this sample, we constrain the spectral parameters to characteristicranges defined from the brightest stars. For X-ray sources with $<$20 netphotons we adopt a conversion factor from detected photon flux to intrinsicflux. This was defined, building on the results for the previous sample, as afunction of the 20% quantile of the detected photon energy distributions, whichwe prove to also correlate well with extinction. We then use the X-rayextinction from the spectral fits to constrain the ratio between optical andX-ray extinction toward Cygnus OB2, finding it consistent with standard"Galactic"' values, when properly accounting for systematics. Finally weexploit the large number of sources to constrain the average coronal abundancesof several elements, through two different ensemble analyses of the X-rayspectra of low-mass Cygnus OB2 members. We find the pattern of abundances to belargely consistent with that derived for the young stellar coronae in the OrionNebula Cluster.

X-ray spectral characterization of the young Cygnus OB2 population