• D. Okamoto
  RCNS, Sendai
• Y. Honda
  KEK, Ibaraki
• T. Sanuki
  Tohoku University, School of Scinece, Sendai

We have designed a beam orbit tilt monitor for stabilizing a beam orbit in ATF2. Once we can measure a beam orbit tilt angle with high precision at one point, we can relate this data with the beam position profile at the focal point. This monitor is composed of a single rectangular cavity and waveguides to extract the signal. This monitor can measure the beam orbit tilt with a single cavity. We extract the signal of one basic resonance mode from the cavity. This electric field mode is perpendicular to the nominal beam axis, and is excited by beam tilt. The magnitude of extracted signal gives us the beam tilt data. According to our simulation, the expected sensitivity is about 30 nrad.