Update on the Time-of-Flight and Position Resolution Measurements in the Proposed Detectors and Cost Estimates – August 2014 WILLIAM TIREMAN NORTHERN MICHIGAN UNIVERSITY DANIEL WILBERN NMU STUDENT RESEARCH ASSISTANT

Discussion Items  Report on the refined measurement of  the dispersion in the time-of-flight of cosmic rays between two plastic scintillator detectors  the position resolution for a cosmic ray hit on the test detector  Cost estimates for 90 0 wedge pieces  Beginnings of a GEANT4 code

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

General Detector Setup/Circuit New Part

Limiting Cosmic Ray Angle with Triple Coincidence  This yields an angle around 6 o  Pulse height cuts on CFD (energy) exclude cosmic rays at larger angles

Measurement Parameters

Conclusion – Updated ConfigurationPosition ΔT FWHM (ps) Position Resolution (cm) Time Dispersion (ps) Plan B – May ± 5 ** 6.78 ± ± 6 Plan B Triple Coincidence 408 ± ± ± 5 Madey et. al. * < 2.5NA155 ± 5 * Madey, R. et al. (1983). Large volume neutron detectors with subnanosecond time dispersions. Nuclear Instruments and Methods in Physics Research, 214(2-3), doi: / (83) ** Corrected value from 2013 collaboration report

Cost Estimates  Stock 4 inch by 12 inch by 24 inch Acrylic plastic sheets can be purchased for about $664 per sheet  Optically clear with light transmission from 300 nm through 700 nm  Can get 36 per sheet if we can tolerate about 1/16 inch less on cut surfaces for the cut and sanding width; otherwise would need double number of sheets  3 sheets would yield 108 wedges – Total ~$2000 plus shipping

Funding Sources and Needs  NMU currently not willing to fund the cost of the plastic stock  NMU Physics has committed to funding the student labor to sand and polish the pieces along with supplies and equipment  2 students, 10 hours per week, 15 weeks, 300 hours – doubt it would all be used  $8.50 (Michigan minimum wage in 2015) so around $2000-$2500  NMU Engineering Tech can cut the pieces; NMU Physics has committed to pay for it with the assumption the price isn’t very high – waiting on word from the engineer  Will need a source of funding for the plastic stock and the labor/supplies for the modifications of the detectors  Recommend modifications be made at Jlab  Possible NMU involvement in this but funding not yet promised

Discussion

First Work on a GEANT4 Simulation for GeN Collaboration WILLIAM TIREMAN AND DANIEL WILBERN NORTHERN MICHIGAN UNIVERSITY AUGUST 2014

Efforts to this point  Kent State code from several years ago has been cleaned up and modified to run more efficiently  Detector Configuration is current  Custom physics lists have NOT been implemented  Visualization and batch mode are available  Particle gun can throw neutrons or protons from a square surface at front array – no angular distribution yet  First steps to extract simulation data has been made (hit a wall)  Uploaded to GitHub

Next steps  Depends on the collaboration’s goal/direction  NMU current goals  Add custom physics list or change as necessary  Expand tracking code  Analyze output; check against “expected” results  Implement multithread code

Discussion

Back up slides

Data for the Plan B Configuration – Update

Plan A – 120 o Bend Configuration Oct 2013

Plan B – 90 o Configuration Oct 2013

Conclusion – May 2013 ConfigurationPosition Resolution (cm) Position ΔT FWHM (ps) Time Dispersion (ps) Plan A8.91 ± ± 9316 ± 15 Plan B6.78 ± ± 6235 ± 7 Madey et. al.< 2.5NA155 ± 5

Typical Spectra