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Summary of the systematic uncertainties

Here I briefly summarize the systematic errors to the normalized yields and distributions of charged pions and kaons. For more detailed discussion see the appropriate section of this chapter. The systematic uncertainty in the calculation of the Cherenkov veto inefficiency is dominated by the statistical uncertainty of the ``lost'' particle counting (see Eq. 4.30).

Table 4.6 shows the sources of systematic uncertainty on $dN/dy$. The error in the extrapolation due to uncertainty in the slope parameter(s) is small because over 95% of particles around mid-rapidity have $p_T$ in the range covered by one of the two angle settings. Consequently, the systematic error in $dN/dy$ is dominated not by the extrapolation, but by uncertainties in determination of centrality and particle ID efficiency. The systematic uncertainty due to centrality was determined from the setting-by-setting variation of acceptance corrected yields of charged tracks, without requiring particle ID. The uncertainty due to PID efficiency corrections arises from statistical uncertainties in the particle counts in untriggered runs used to determine the veto correction.

Table 4.11: Summary of fractional systematic errors to the normalized yields. Positive kaons in the weak field high angle spectrometer setting are chosen as ``representative''. Maximum and minimum uncertainties indicate the range; the overall systematic uncertainty was evaluated for each setting separately.

case	centrality	PID	$p_T$ extrapolation	total
representative	0.081	0.042	0.0067	0.098
maximum in any setting	0.081	0.25	0.063	0.26
minimum in any setting	0.058	0.014	0.0042	0.058