1. Nuclear Experimentation
Dr. Stephanie Lyons

2. The day so far: NOW: Looking ahead: Basics of nuclear physics
Smashing nuclei Toured NSCL Lectures Laboratory experiments
NOW:
Basics of nuclear physics
Discuss what research looks like
Looking ahead:

3. High Z Superheavies Proton Rich Neutron Rich
Why doesn’t the valley of stability follow N=Z line?
Proton Rich
Neutron Rich
protons, Z
neutrons, N
Courtesy of A. Spyrou

4. Nuclear Nomenclature Element Isotope Isotone Isobar protons, Z
neutrons, N

5. What would we like to know?
General Properties:
Mass
Life-time
Decay Mode
protons, Z
neutrons, N

6. Calculate Mass
Essentials and Conversions: mp = amu mn = amu 1 amu = x kg 1 MeV = x Joules +
42He 2p 2n

7. BINDING BLOCKS Essentials and Conversions: mp = 1.00727647 amu
GOAL: Build a section of the nuclear chart based on binding energy with Legos.
As a group calculate the binding energies for your isobars.
Compare to the tile board:
If Correct you can build your isotopes
If Not, go back to the calculations to determine the error and try again.
Continue building the chart
Discuss
Essentials and Conversions:
mp = amu
mn = amu
1 amu = x kg
1 MeV = x Joules

8. How else can we use nuclear binding energy?

9. What does this tell us about how matter is created and transformed?
pp-chain

10. Z N Stellar burning pp chain rp / νp process p process s process
r process
56Fe
Stellar burning
pp chain N

11. How can we best answer questions about how nuclei are created?

12. Scientific Method Identify question/problem
Can I design an experiment to learn something new?
Propose experiment [NSCL Proposal Advisory Committee accepts ~50% of proposed experiments]
Design, build new equipment, schedule experiment
Run experiment (5-10 days, running 24/7)
Data analysis (~3 months – 2 years)
Compare to theory (if possible)
Publish results

13. How are elements heavier than iron formed?
What questions can we ask about this process?
Question: How do certain nuclei go through beta-decay?

14. Scientific Method Identify question/problem
Can I design an experiment to learn something new?
Propose experiment [NSCL Proposal Advisory Committee accepts ~50% of proposed experiments]
Design, build new equipment, schedule experiment
Run experiment (5-10 days, running 24/7)
Data analysis (~3 months – 2 years)
Compare to theory (if possible)
Publish results

15. Designing an experiment:
What are requirements to be able to accurately answer my science question
Let’s make a list
Is there a laboratory that best suits the needs of my experiment
YES: Proposal! – if accepted we can schedule
NO: What development needs to occur to be able to do this?
Design experiment to best extract all of the required information for your science question
What data are needed?

16. Scientific Method Identify question/problem
Can I design an experiment to learn something new?
Propose experiment [NSCL Proposal Advisory Committee accepts ~50% of proposed experiments]
Design, build new equipment, schedule experiment
Run experiment (5-10 days, running 24/7)
Data analysis (~3 months – 2 years)
Compare to theory (if possible)
Publish results

17. Experimental Set-up
Isotopes of interest delivered to experimental end station
SuN
Detector for Particle Identification
Implantation and B-decay detector

18. Data that was collected:
Particle entering end station
Implantation energy and time
Subsequent beta-decay and time
De-excitation of daughter nucleus

19. Scientific Method Identify question/problem
Can I design an experiment to learn something new?
Propose experiment [NSCL Proposal Advisory Committee accepts ~50% of proposed experiments]
Design, build new equipment, schedule experiment
Run experiment (5-10 days, running 24/7)
Data analysis (~3 months – 2 years)
Compare to theory (if possible)
Publish results

20. Data Analysis and Results:
t ½= 213 ± 18 ms
t ½(lit.)= 227 ms
Time (ms)
Counts
69Co
t ½= 85 ± 10 ms
t ½(lit.)= 80 ms
Counts
71Co Co
Time (ms)

21. Final results demonstrate improvement in our knowledge
1821.2
1517.6
915.3
321 (3.5s)
0.0
0.0 (227 ms)
69Co
69Ni
Qβ= 9.81 MeV
69Co decay
71Co decay

22. Summary Nuclear binding energy
How it’s calculated
What it can tell us
How real research is performed Still use scientific method
Went through the process for an experiment recently performed at the NSCL