arXiv subjects

Richard W. Helms

Publications and source records attributed to Richard W. Helms.

2 recordsLinked to original sources

arXiv2012

Motion Tracking in Undergraduate Physics Laboratories with the Wii Remote

We report the incorporation of the Wiimote, a light-tracking remote control device, into two undergraduate-level experiments. We provide an overview of the Wiimote's basic functions and a systematic analysis of its motion tracking capabilities. We describe the Wiimote's use in measuring conservation of linear and angular momentum on an air table, and measuring the gravitational constant with the classic Cavendish torsion pendulum. Our results show that Wiimote is a simple and affordable way to streamline the data acquisition process and produce results that are generally superior to those obtained with conventional techniques.

physics.ed-ph↗

arXiv2004

Orbit and Optics Improvement by Evaluating the Nonlinear BPM Response in CESR

We present an improved system for orbit and betatron phase measurement utilizing nonlinear models of BPM pickup response. We first describe the calculation of the BPM pickup signals as nonlinear functions of beam position using Green's reciprocity theorem with a two-dimensional formalism. We then describe the incorporation of these calculations in our beam position measurements by inverting the nonlinear functions, giving us beam position as a function of the pickup signals, and how this is also used to improve our measurement of the betatron phase advance. Measurements are presented comparing this system with the linearized pickup response used historically at CESR.

physics.acc-ph↗