Joint Institute for Nuclear Astrophysics

1. Joint Institute for Nuclear Astrophysics Marble Nuclei Activities For use with “Learning Nuclear Science With Marbles” version 4.1 JINA is supported by the National Science Foundation through the Physics Frontier Center program.

2. Isotope BINGO (pg 2-3) • Rules • Leader will call out type of isotope (e.g. “oxygen”) and you pick one of that type • Need help? Check legend at bottom right • Don’t write on your BINGO cards, use scraps of paper to cover your isotopes • Write numbers on the scraps to indicate which order you played the (first = 1, etc) • Carbon-12 is a free space • Five in a row to win; four corners is cheap

3. Nucleosynthesis Game (pg 4-5) • Rules • Teams of 2 with your marbles, dice and QRS • Take turns rolling and following instructions on page 5 • Check your Chart after every change; if your new nucleus isn’t on there, go back to the nucleus you had before! • “Bombardment” on 2 or 12 is optional • First team to make an oxygen or heavier (8+ protons) nucleus wins!

4. Big Bang Nucleosynthesis (pg 6) • Rules • Start with 7 yellow protons and 1 green neutron • Keep protons in left hand, neutron or anything you make in right hand • Move around the room and perform allowed “reactions” with different people • Need help? Check the list of allowed “reactions” – usually, two people should have the particles to perform one of them • Got Helium-4? You win, sit down

5. The p-p chain (pg 7) • Rules • Start with 4 yellow protons and a die • Always keep loose protons in left hand, anything you make with them in right hand • Move around the room, each time you meet a person compare your particles • Both only have protons? Put them together and roll dice • Different numbers? Take back your proton and move on • Same numbers? Switch one proton to a (green) neutron and roll to see who keeps the p+n, then move on • One or both of you have something more than just protons? Figure out which reaction you can do on the right, put them together, roll to see who keeps it, then move on • Got Helium-4? You win, sit down

6. Fragmentation Box (pg 8-11) • Rules • Play with your marbles for 2 minutes • Start following instructions with step 1, “Acceleration” • Take turns being the reader • Make sure everyone gets to smash marbles • Need help? Re-read instructions, then ask • Try to do all steps 1-4 (“acceleration” thru “creating rare isotopes”) • Most important part: smash C-12 three times in “creating rare isotopes” and write the three isotopes you make on the board

7. Neutron Capture Processes (pg 12) Big Bang Big Bang Stellar fusion Stellar fusion Human-made Not naturally-occurring

8. Red giants and supergiants

9. Heavier elements thru neutron capture • Free neutrons are created by nuclear reactions in a red giant • Stable nucleus absorbs a neutron, making it neutron-rich and unstable • Unstable nucleus releases energy/becomes stable by beta decay, turning a neutron into a proton • Final nucleus has more protons/is a heavier element than original nucleus • New stable nucleus absorbs a neutron…

10. Neutron-capture process

11. Beta-minus decay

12. Which way will it go? What determines whether an unstable isotope will decay OR capture another neutron?

13. A helpful legend Remember: the two beta decays go opposite ways!

14. Plotting the “s-process” Assume a neutron capture every 10 years Work with a partner • If half-life > 10 yr then capture • If half-life < 10 yr then decay Hard mode/if you have time: If 5 yr < half-life < 20 yr then follow BOTH capture and decay paths

15. Plotting the “r-process” Assume a neutron capture every 100 milliseconds (ms) Work with a partner • If half-life > 100ms then capture • If half-life < 100ms then decay Hard mode/if you have time: If 50ms < half-life < 200ms then follow BOTH capture and decay paths

16. A full r-process simulation Black boxes are stable isotopes Protons (Elements) Iron common rare Neutrons (Isotopes) Nuclei are bombarded with neutrons, forming rare isotopes that will decay into stable heavy elements