AN ELECTROSTATIC ION TRAP FOR FOURIER TRANSFORM MASS SPECTROMETRY Matt Lappin 1

THE AUTORESONANT ION TRAP MS ● A.V. Ermakov and B.J. Hinch of Rutgers used a similar trap in their autoresonant ion trap mass spectrometer (ART-MS) ● Verified f is proportional to 1/(m/z) ½ for ions in the mass range Da ● ART-MS uses resonant ejection, not FT-MS, which requires RF sweep Ermakov, A.V.; Hinch, B.J. An autoresonant ion trap mass spectrometer. Rev. Sci. Instrum. 81, (2010); doi: /

THE ELECTROSTATIC HARMONIC POTENTIAL ION TRAP 1 kV, switched 3A current source Held at a positive potential (5V) Can be pulsed to 10V Plate to protect macor filament clamp (0V) To detector (0V) for image current detection The trap is 2.5” long and has a 1” diameter.

ION PRODUCTION AND ANALYSIS 5 V 0 V

ION PRODUCTION AND ANALYSIS 1000 V 0 V

SIMION SIMULATION PARAMETERS ● Pulse time: 5 microseconds ● Trapping potential delay: 17 microseconds ● Trapping duration: 1 millisecond Scientific Instrument Services, Inc., Ringoes, NJ,

● Stainless steel plates and alumina tubes/spacers: Kimball Physics eV parts ● Assembled by Caltech CCE Insturment Shop Source Trap Trapping plates(1kV) Signal plate CONSTRUCTION

VACUUM CHAMBER/FLANGE BNC SHV 10-pin instrumentation

ELECTRONICS Vacuum

ELECTRONICS

SIGNAL DETECTION CIRCUITS Image Charge Detection Mass Spectrometry: Pushing the Envelope with Sensitivity and Accuracy. John W. Smith, Elizabeth E. Siegel, Joshua T. Maze, and Martin F. Jarrold. Analytical Chemistry (3), Image Credit: Amptek, Inc.

LABVIEW ● The system is designed to run through LabVIEW ● Parallel threads to control the instrument timing, data acquistion, and user input separately ● Data will be taken at 1MS/s in order to have enough data points to accurately perform FFT and prevent aliasing

SUMMARY AND CONCLUSIONS ● Verified that the instrument should work based on SIMION simulation ● Instrument assembly is in progress ● Tests to come after the completion of assembly

ACKNOWLEDGMENTS I would like to thank all members of the Beauchamp group, especially Professor Beauchamp and graduate student Daniel Thomas, for all of your help. I would also like to thank Jeff Groseth in the CCE Electronics shop for helping with the assembling the electronics for the spectrometer, and the CCE Machine shop for help with machining and assembling parts of the instrument.