Han, B. Murray, S.N. Pennisi, T.R. Peplov, V.V. Saethre, R.B. Stinson, C. Stockli, M.P. Welton, R.F. JACoW Publishing Geneva, Switzerland 978-3-95450-200-4 10.18429/JACoW-ICAP2018-WEPAF02 English 325-329 WEPAF02 rfq simulation LEBT gun operation Contribution to a conference proceedings 2019 2019-01 https://doi.org/10.18429/JACoW-ICAP2018-WEPAF02 http://jacow.org/icap2018/papers/wepaf02.pdf The LEBT chopper is a critical element of the SNS accelerator system. In this work, the benefit of increasing the chopping voltage amplitude for the present chopping pattern is shown with beam simulations, and an ongoing hardware upgrade of the chopper pulser units is discussed. In addition, with the prospect of higher voltage capability of the new pulser design, two alternative chopping patterns which reduce the switching frequency of the chopper pulsers down to 1/2 or 1/4 of the present chopping pattern, are also explored with beam simulations.