The PAU Survey: Spectral features and galaxy clustering using simulated
  narrow band photometry
  We present a mock catalogue for the Physics of the Accelerating Universe
Survey (PAUS) and use it to quantify the competitiveness of the narrow band
imaging for measuring spectral features and galaxy clustering. The mock agrees
with observed number count and redshift distribution data. We demonstrate the
importance of including emission lines in the narrow band fluxes. We show that
PAUCam has sufficient resolution to measure the strength of the 4000\AA{} break
to the nominal PAUS depth. We predict the evolution of a narrow band luminosity
function and show how this can be affected by the OII emission line. We
introduce new rest frame broad bands (UV and blue) that can be derived directly
from the narrow band fluxes. We use these bands along with D4000 and redshift
to define galaxy samples and provide predictions for galaxy clustering
measurements. We show that systematic errors in the recovery of the projected
clustering due to photometric redshift errors in PAUS are significantly smaller
than the expected statistical errors. The galaxy clustering on two halo scales
can be recovered quantatively without correction, and all qualitative trends
seen in the one halo term are recovered. In this analysis mixing between
samples reduces the expected contrast between the one halo clustering of red
and blue galaxies and demonstrates the importance of a mock catalogue for
interpreting galaxy clustering results. The mock catalogue is available on
request at https://cosmohub.pic.es/home.
