Correlation function for the stack of the 100 mocks in four ranges of μ. The red points represent the measured correlation function of the mocks with metals and the red curves shows the best fit. The black points indicate the correlation function after including, in addition to metals, HCDs unmasked for N_HI< 10²⁰ cm^-2 and the black curve the best fit. The peak at r ~ 60 h^-1 Mpc due to SiIIa and SiIIb is apparent in the range μ> 0.95 but not in the range 0.8 <μ< 0.95.