X-ray observations, and in §4 we presented the ALMA archival data available for the two targets. In §5 we discuss our estimates of the properties for the two targets together with their implication for co-evolutionary models. Our conclusions are finally summarized in §6.

In this work, we adopt the standard flat cosmology (Planck Collaboration XIII 2016) with round parameter values: matter density $\Omega_M = 0.32$, baryon density $\Omega_b = 0.05$, Hubble constant $H_0 = 100\,\hbox{h}\,\hbox{km}\,\hbox{s}^{-1}\,\hbox{Mpc}^{-1}$ with $h=0.67$, and mass variance $\sigma_8 = 0.83$ on a scale of $8\,\hbox{h}^{-1}\,$Mpc. Stellar masses and SFRs (or luminosities) of galaxies are evaluated assuming the Chabrier (2003) IMF.

The targets: SDP.9 and SDP.11 {#sec:targets}
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SDP.9 (HATLAS J090740.0-004200) and SDP.11 (HATLAS J091043.1-000322) were firstly detected in the HATLAS first observations of a field $4\times4$ sq. deg. in size, taken during the Science Demonstration Phase (SDP, Maddox et al. 2010), that reached a 5$\sigma$ noise level of 33.5 mJy/beam at 250 micron (Negrello et al. 2010). They have a flux density above 100 mJy at 500 $\mu$m and are detected both in the SPIRE and PACS bands (i.e. between 100 to 500 $\mu$m, Eales et al. 2010, Poglitsh et al. 2010).

The Z-Spec spectrometer observed the 