Estimate of the total radiation lengths during E 01 - 012

The radiation lengths needed for the radiative corrections, for the nitrogen dilution and elastic analyses are calculated in this note. 1 Polarized He cells 1.1 Wall and window thicknesses 1.1.1 Duke The wall and window thickness measurements were done by Jaideep Singh [1]. The average value for wall thicknesses measured by Vince Sulkosky [2] were very similar: 1.42 mm for the left side∗ and 1.38 for the right side. LEFT RIGHT position thickness (mm) position thickness (mm) A 1.52 E 1.42 B 1.38 F 1.47 I 1.42 J 1.39 C 1.37 G 1.42 D 1.38 H 1.22 avg. 1.41 avg. 1.38 Table 1: Duke wall thicknesses. measurement upstream (A) downstream (B) method (μm) (μm) opt. 108 137 mech. 105 132 Table 2: Duke window thicknesses. ∗If window A is upstream, then walls (A,B,I,C,D) faced the left HRS.