Monday, February 13, 2017

Spring 2017 CHEM 312: Lecture 6 Gamma Decay

Gamma decay is described in two lectures. The first lecture covers the fundamentals of gamma decay and second lecture describes Moessbauer spectroscopy. Different methods to find data on gamma decay yields for decay of isotopes are presented. The energetics involved in gamma decay are provided. This includes recoil from gamma, which is exploited in Moessbauer spectroscopy. Decay types in gamma transitions are explained, focusing on electromagnetic basis for the gamma emission. Transition probabilities and internal conversions inherent to gamma decay are covered. Isotope examples for internal conversion electrons are given. Angular correlations in gamma decay are described with an experimental example provided. The use of gamma decay in Moessbauer spectroscopy is discussed. Part 1 is 34 minutes and part 2 is 28 minutes. The lecture is assigned 14-Feb-17 and PDF Quiz 6 is due 21-Feb-17.

24 comments:

  1. Hello, I have completed the lecture and have sent you my quiz via email. I enjoyed the lecture, and feel like I have a greater intuition of what it means for an atom to be metastable. Thank you!

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  2. for the question 3: i just use the website you provided on the Radiation search page, i put the energy number and 239Np, i will get the %gamma directly, it is right?

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    1. correct. One could just enter the isotope and all the gammas will be presented.

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  3. fro the question 2: only one answer is correct ?

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  4. Just sent in my quiz, thanks for a good lecture

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  5. For question 1 the gamma decay energies need to match the difference between the excited states. If the excited state goes directly to the ground state, then the gamma energy is equal to the energy at the excited state. From deexcitations that occur between states, the gamma energy is the difference between the states.

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  6. Just sent an email with my quiz. Thanks.

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  7. I finished this lecture and sent the PDF quiz 6 to you as an attachment via email.

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  8. PDF Quiz 6 has been sent via email. Thank you!

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  9. I have submitted Quiz 6, Thanks.

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  10. I've finished the lecture and sent in the quiz.

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  11. submitted my quiz.. oh not sure if anyone else had issues this weekend on accessing the lecture link and this morning as well. Then again I was using UNLV's web server and PC ;-/

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    Replies
    1. Thanks for the comments on the server issues. Please keep me posted on this.

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  12. Just submitted quiz 6 and finished the lecture 6 on youtube.

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  13. Thanks for the comments and submissions!

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