Selection of Cepheids from PS1 and WISE data

The thought is to use the known sample of 85 Cepheids (with PS1 data) to do explore
by hand cuts.  The basic philosophy is:

1. Cepheids have to appear as bright sources in W1 and W2. Why? According to Freedman et al 2006-ish (LMC-based) even the short-period (2-day) least luminous Cepheids have M_W1 or M_W2 of about -3.55. So, if we consider a DM_max=15 for now, and A_V~15mag (A_W1~0.7mag), then we have m_W1 and m_W2 < 12.5
2. Cepheids have intrinsic W12 colors in a narrow range, -0.07<W12<0.2
   
3. The 84 Cepheids with PS1 data fall into a well defined patch of Hernitschek's variability amplitude omega_best and time-scale tau_best space: 0.08<omega_best<0.5 and 0.7days < tau_best<30days.
   

Taking the test regions from Laura (15' around Cepheids?) , we go from 1Million sources to 220, and still retain 79 of the 84 Cepheids

Note added: a W12 -- (J-K) cut may also be interesting

That leads to a candidate list that is very peaked to the plane

or, as seen on sky:

The file with the candidate sample is n this fits file: https://www.dropbox.com/s/5zoi4o9diip01pg/Hernitschek_catalog_WISEbright_W12-JKcut_omnega-tau-cut.fits?dl=0

Is the next step to run period fitting on these 7000 candidates?