1. Time-of-Flight and Position Resolution in Proposed Detectors DR. WILLIAM TIREMAN NORTHERN MICHIGAN UNIVERSITY MR. DANIEL WILBERN NMU RESEARCH ASSISTANT

2. Goals  Measure the dispersion in the time-of-flight of cosmic rays between two plastic scintillator detectors  Measure the position resolution for a cosmic ray hit on the test detector

3. Neutron Research Red – charged particle taggers Green – Neutron Bars Neutrons knock protons out and they scatter up and down into the detectors Picture from: Dr. Andrei Semenov, University of Regina, Canada

4. Pictures from: Dr. Andrei Semenov, University of Regina, Canada

8. General Detector Setup/Circuit

9. Measurement Parameters

10. Typical Spectra

11. Plan A – 120 o Bend Configuration

12. Plan B – 90 o Configuration

13. Conclusion ConfigurationPosition Resolution (cm) Position ΔT FWHM (ps) Time Dispersion (ps) Plan A8.91 ± 0.13446 ± 9316 ± 15 Plan B6.78 ± 0.08333 ± 6235 ± 7 Madey et. al.< 2.5NA155 ± 5

14. References Madey, R. et al. (1983). Large volume neutron detectors with subnanosecond time dispersions. Nuclear Instruments and Methods in Physics Research, 214(2-3), 401-413 doi: 10.1016/0167-5087(83)90608-7

15. Using Small Detector Energy to Limit Cosmic Ray Incident Angle