The effects of temperature variation on electron beams with RF voltage modulation

The correlation between the horizontal beam size vs. the cavity temperature, observed at the Taiwan Light Source (TLS), is explained by the combined effects of (1) cavity resonance frequency shift resulting from temperature change, (2) cavity voltage and synchronous phase angle change resulting from uncompensated beam loading in the low-level rf-feedback system, and (3) rf cavity voltage modulation for alleviating the coupled bunch instability. This experimental method can be used to evaluate the intrinsic resolution of the low-level rf-feedback system