G2P: Gadget2 massive production with Planck cosmology
Shot noise study for G2P15-100
(Left panel) the power spectra predicted using both CAMB linear and non-linear models from Planck 2015 are illustrated. (black solid and dashed lines) It also shows the average of the measured power spectra over 100 non-fixed amplitude simulation realizations in 1.89Gpc/h box with(green cross) and without(blus plus) the shot-noise subtraction. (Right panel) The power spectra in the left panel with respect to the CAMB linear spectrum are depicted. The sheded horizontal area in grey indicates the 1% deviation from the linear prediction. Note that since we utilize regular grid distribution for the initial condition, the shot noise caused by the randomness is suppressed in the measured power spectrum at high redshfits (z > 1), where we found that the linear prediction(black solid lines) matches well with the measured power spectrum without subtracting the shot noise(blue plus). Thus, we didn't subtract the shot noise at these high redshifts. (ref. Section 3.1. of D. Jeong's dissertation) At low redshifts(z < 1), the level of shot noise is relatively small to the clustering power and does not make significant difference between green cross symbols and blus plus symbols. Other than the shot noise subtraction, the window fuction correction for the Cloud-in-Cell (CIC) mass assignment in FFT is done for all measured power spectrum