NOISE SOURCES

In the following an attempt is made to categorize important noise sources discussed throughout the paper on different time scales:

• Short term ($<$1 hour): Ground vibration induced by human activities, mechanical devices like compressors and cranes or external sources like road traffic potentially attenuated by concrete slabs, amplified by girder resonances and spatial frequency dependent orbit responses, ID changes (fast polarization switching IDs $<$100 Hz), cooling water circuits, power supply (PS) noise, electrical stray fields, booster operation, slow changes of ID settings. Sources of beam motion associated with synchrotron oscillations and single- and coupled bunch instabilities are not considered [1].
• Medium term ($<$1 week): Movement of the vacuum chamber (or even magnets) due to changes of the synchrotron radiation induced heat load especially in decaying beam operation, water cooling, tunnel and hall temperature variations, day/night variations, gravitational sun/moon earth tide cycle.
• Long term ($>$1 week): Ground settlement and seasonal effects (temperature, rain fall) resulting in alignment changes of accelerator components including girders and magnets.