E. Brost 18/6/09 CHESS & LEPP Good Vibrations Vibration studies at CHESS Elizabeth Brost Mentor: Peter Revesz, Don Hartill CLASSE Physics REU June 18, 2009

E. Brost 18/6/09 CHESS & LEPP Outline Goals Experimental Setup Preliminary results Plans for the rest of the summer

E. Brost 18/6/09 CHESS & LEPP Goals Study the vibrations in: –F-Cave, F3 hutch –Capillary puller –CESR components Find out what’s causing the vibrations Plan how to stop the vibrations

E. Brost 18/6/09 CHESS & LEPP Experimental Setup (F-Cave) ¾” copper coil flow meter me accelerometer water on/off coil #11 (out) coil #1 (in) (Sol Gruner’s design for the experimental setup)

E. Brost 18/6/09 CHESS & LEPP Piezoelectric Accelerometer Mass Piezoelectric cantilever G Voltage

E. Brost 18/6/09 CHESS & LEPP Collecting Data ADC Amplifier Accelerometer Water flow Laptop 10V/g

E. Brost 18/6/09 CHESS & LEPP Software Windowing: Blackman Sample frequency: 2500 Hz 8192 samples Range: Hz Amplifier gain: 1000 Performs FFT! (Software deigned by Peter Revesz)

E. Brost 18/6/09 CHESS & LEPP A little bit of Digital Signal Processing 105Hz sine wave from a function generator V(t) V(f) V(t) V(f) g(f) A(f) g(f) = C*V(f) (C = 9.9 V/g) A(f) = - (1/ω 2 )g(f) (ω = 2πf) FFT

E. Brost 18/6/09 CHESS & LEPP Preliminary Results concrete floor vs. input coil

E. Brost 18/6/09 CHESS & LEPP Preliminary Results input coil – water on vs. water off

E. Brost 18/6/09 CHESS & LEPP Preliminary Results input coil vs. output coil water out water in

E. Brost 18/6/09 CHESS & LEPP Conclusions Water flow in the cooling coils is a significant source of vibrations, especially at low frequencies Constraining the coils helps to get rid of some low-frequency vibrations

E. Brost 18/6/09 CHESS & LEPP Plans for the rest of the summer Continue vibration studies in the F-cave and in other areas of CHESS Identify the source of the vibrations Stop the vibrations!!

E. Brost 18/6/09 CHESS & LEPP Acknowledgements Peter Revesz, Don Hartill Sol Gruner Richard Galik, Georg Hoffstaetter, Ernie Fontes, Lora Hine NSF Everyone at CHESS

E. Brost 18/6/09 CHESS & LEPP References C. Mercer, “Acceleration, Velocity and Displacement Spectra Omega Arithmetic,” Prosig Signal Processing Tutorials (2006).

E. Brost 18/6/09 CHESS & LEPP Backup Slides

E. Brost 18/6/09 CHESS & LEPP Windowing (Before) square

E. Brost 18/6/09 CHESS & LEPP Windowing (After) Bartlett Hanning Hamming Blackman