Corrigendum to TPC in γ-ray astronomy above pair-creation threshold' [Nuclear Instruments and Methods in Physics Research A 701 (2013) 225-230]

摘要

In Nuclear Instruments and Methods in Physics Research Section A 701 (2013) I have obtained the low-energy and high-energy single-track angular resolution from the optimal expressions established by Innes [11], from which I studied the properties of a TPC-based gamma-ray telescope. During the validation of a Kalman filter-based fit, it was found that the high-energy asymptote was over-estimated by a factor of 4. The discrepancy was tracked to be due to my studying fits of tracks with an intercept and a slope as free parameters, without a curvature, while Ref. [11] was studying fits of tracks with a curvature. In the latter case, when the track angle is estimated at the beginning of the track, the correlation between angle and curvature enlarge the uncertainty by a factor of 4 (Compare Eqs. (5) and (9) of [Nuclear Instruments and Methods in Physics Research A 589 (2008) 109-117].