• C.-Y. Tan
  

In the classical chromaticity measurement technique, chromaticity is measured by measuring the change in betatron tune as the the RF frequency is varied. This paper will describe a way of measuring chromaticity: we will phase modulate the RF with a known sine wave and then phase demodulate the betatron frequency . The result is a line in Fourier space which corresponds to the frequency of our sine wave modulation. The peak of this sine wave is proportional to chromaticity. For this technique to work, a tune tracker PLL system is required because it supplies the betatron carrier frequency. This method has been tested in both the SPS and Tevatron and we will show the results here.

• C.-Y. Tan
  
• V. H. Ranjbar
  Tech-X, Boulder, Colorado

In the classical head-tail chromaticity measurement technique, a single large kick is applied transversely to the beam. The resulting phase difference between the head and the tail is measured and the chromaticity extracted. In the continuous head-tail kicking technique, a very small transverse kick is applied to the beam and the asymptotic phase difference between the head and the tail is found to be a function of chromaticity. The advantage of this method is that since the tune tracker PLL already supplies the small transverse kicks, no extra modulation is required.

• J. Ruan
  
• H. Edwards, V. E. Scarpine, C.-Y. Tan, R. Thurman-Keup
  Fermilab, Batavia, Illinois
• YL. Li, J. G. Power
  ANL, Argonne, Illinois
• T. J. Maxwell
  Northern Illinois University, DeKalb, Illinois

The free space electro-optical (EO) sampling technique is a powerful tool for analyzing the longitudinal charge density of an ultrashort e-beam. In this paper, we present

1. experimental results for a laser-based mock-up of the EO experiment* and
2. a design for a beam-based, single-shot, EO sampling experiment using the e-beam from the Argonne Wakefield Accelerator (AWA) RF photoinjector.

* Yuelin Li, Appl. Phys. Lett. 88, 251108, 2006