Positron background for test run

$$\sigma \propto \frac{(\char93 \mathrm{of}~\mathrm{events})\times (\mathrm{scale... ...rm{accepted}~\mathrm{triggers}} \times\frac{1}{\mathrm{target}~\mathrm{length}}$$ (1)

$$\frac{\sigma_{e^+}}{\sigma_{e^-}} = \frac{N_{e^+}}{N_{e^-}}\times \frac{[\mathrm{accepted}~\mathrm{tr... ...~\mathrm{charge}]_{e^+}} {[\mathrm{scaler}~\mathrm{per}~\mathrm{charge}]_{e^+}}$$

$$\mathrm{for }~~ p_e = 1.5 \mathrm{GeV/c}~~~~~ \frac{\char93 2786}{\char93 2773} = \frac{70}{29185} \times\frac{393070\times 4}{1803176\times 15} \times\frac{62367.3}{3121.6}$$ (2)

$$= 0.28\% \nonumber$$

$$\mathrm{for }~~ p_e = 0.9 \mathrm{GeV/c}~~~~~ \frac{\char93 2791}{\char93 2776} = \frac{611}{3980} \times\frac{303126\times 4}{1805844\times 15} \times\frac{1171888.0}{71144.2}$$ (3)

$$= 11.32\% \nonumber$$

$$\mathrm{for }~~ p_e = 0.55 \mathrm{GeV/c}~~~~~ \frac{\char93 2778}{\char93 2815} = \frac{1679}{10372} \times\frac{926232\times 4}{1809950\times 15} \times\frac{3394497.9}{198813.6}$$ (4)

$$= 37.72\%$$