Integration of a Clover Detector with the necessary electronics and computer program to utilize the ADDBACK method An SP496 and Capstone Research Project Midshipman First Class Jack Hathaway Advised by Assistant Professor Daryl Hartley, Ph.D.

Co60 Energy Unstable Co γ-ray 1332 γ-ray Stable Ni60 Time Emitted Beta Particle Emitted Gamma rays Unstable Ni60 Beta Decay

So how do we ‘see’ all of this happening? What kind of detector do we need?

When my advisor was a student … Bell bottoms were cool… The Beetles first appeared on stage… …and nuclear physicists used Sodium Iodide (NaI) Detectors…

High Density = Great Efficiency Poor Energy Resolution from detection system

While I was busy watching Transformers … Nuclear physicists developed Germanium (Ge) Crystal Detectors…

Low Density = Low Efficiency Great Energy Resolution from detection system

Low Density = Low Efficiency Great Energy Resolution from detection system Can we have the best of both? High efficiency and good resolution?

Clover detector An array of four Germanium Crystals, physically and electronically independent

Clover Detector Source Location 25 cm

Anode Cathode

The Basic Electronics: Spec Amp KMAX Program Channel Number Number Of Counts Crystal 1 Channel Number Number Of Counts Crystal 3 Channel Number Number Of Counts Crystal 2 Channel Number Number Of Counts Crystal 4 Channel Number Crystal 10 Crystal 2600 Crystal 30 Crystal 40 ADC The KMAX program displayed 5 counts, but there were only 3 Events…. Were there 5 gamma rays or only 3?

Mission: Utilize the Clover Detector as an array rather than four single detectors to give the researcher the best data possible Solution: Integrate the Clover Detector into the necessary electronics and create a computer program to utilize the ADDBACK Method

What is ADDBACK? Addback Flash created by Dave Campbell, Florida State University

Coding ADDBACK Computer Input Channel Number Crystal 10 Crystal 2600 Crystal 30 Crystal 40 Define an event Step 1: Event 1 Each event corresponds to a single gamma ray interacting with the detector. One Gamma ray = One Event = One Coincidence Window

Output group 1 Output group 2 Fast Amp Logic ‘OR’ Gate Spec Amp Analog to Digital Converter Inputs Output to Computer Step 2: Creating an electronic Coincidence Window Event 1Channel Number Crystal 1600 Crystal 20 Crystal 3400 Crystal 4200 ADC Gate Gate Delay Generator

Step 3: Applying calibrations Event 1Channel Number Crystal 1600 Crystal 20 Crystal 3400 Crystal 4200 Channel Number Crystal 2 Channel Number Crystal 1 Counts Channel Number Crystal 3 Channel Number Crystal 4 Counts Energy

Step 4: Executing ADDBACK ADDBACK = = 1173 Event 1Channel Number Energy Crystal Crystal 20 0 Crystal Crystal Event Event Event Event 4997 Totals ADDBACK Event 1560, 412, 201 Event Event Event 4746, 251 Separate Crystals Event 2Channel Number Energy Crystal Crystal 20 0 Crystal 30 0 Crystal = 1332 Event 3Channel Number Energy Crystal 10 0 Crystal 20 0 Crystal Crystal = 1173 Event 4Channel Number Energy Crystal 10 0 Crystal Crystal 30 0 Crystal = 997 3:1 ratio (actual 25%)2:5 ratio (actual 14%) Peak to Background

Results

- Longer Runs - Proton Resonance - Polarization Future Goals

Acknowledgements Advisor: Assistant Professor Daryl Hartley, Ph.D. Witty quips and technical advice: Professor Jeff Vanhoy, Ph.D. Stunts and Modeling: MIDN 1/C Drew Barker, roommate

Scratch-work slide Background Detector pictures? Clover Picture

The Basics: Spec AmpADC KMAX Program Channel Number Number Of Counts Crystal 1 Channel Number Number Of Counts Crystal 3 Channel Number Number Of Counts Crystal 2 Channel Number Number Of Counts Crystal 4 Coding ADDBACK Event 1 Event 2 Event 3 1 Count 2 Counts The KMAX program displayed 5 counts, but there were only 3 Events…. Were there 5 gamma rays or only 3?

Pre-Amp Double outputs, same signal from each crystal Interior to the Clover Detector

What is a Coincidence Window? Ekg thingermabober of science! Input 32 microseconds ADC Gate Delay Generator Output

Question slide on the PMT NaI detectors