S-process model (nucleosynthesis)

[big man]

Sorry for all these questions...I just want to be really prepared for the exam I have in a couple of weeks.

In the exam we will most likely have to look at the s-process model (it's an exam on the computer) that he showed us in class. He said that we should look at it now to make sure that we know exactly how to do the given exercises so that we don't waste time in the exam.

The model is attached.

Here are the things he said that you have to do:

incorporate radioactive decay
incorporate r-processing

I know how to do the basic first exercise where you need to obtain predicted abundances that are close to the actual cosmic abundances, but the above sections I'm not sure how to do at all. I know that the reason that the predicted abundances will not exactly match the actual is because the s-process model does not include the effect of the r-process
in some the isotopes that have both s- and r-processes.

I understand that this is probably a bad question to ask 'cause it might involve too much time, but I thought I'd just ask on the off chance that someone might know right off. I will keep reading up on this material to see if I can get my head around it anyways.

Thanks for any help

P.S. there is an error in the code at Abloss[2]...the it has to be MAC[2] not [3].

View attachment s-modelBa3.mws

 

[Jhero]

Thank you for your post and for being diligent in preparing for your upcoming exam. Incorporating radioactive decay and r-processing into the s-process model can be a bit tricky, but with some practice and understanding, you will be able to master it.

To incorporate radioactive decay, you will need to add a term in the equations for the abundance of each isotope that decays. This term will depend on the half-life of the isotope and the rate of decay. You can find this information from reliable sources or your textbook. This will allow you to calculate the abundance of the isotope at any given time, taking into account its decay.

Incorporating r-processing can be done by adding an additional term in the equations for the abundance of isotopes that undergo both s- and r-processing. This term will depend on the rate of r-process and the abundance of the parent isotope. Again, you can find this information from reliable sources or your textbook.

As for the exercise of obtaining predicted abundances that match the actual cosmic abundances, it is important to note that the s-process model may not be able to fully account for the abundance of some isotopes due to the presence of r-process. This is where the discrepancy between predicted and actual abundances may occur. However, you can still make adjustments to your model by adjusting the rates of r-process and incorporating it into your calculations to try and achieve a closer match.

I understand that this may seem overwhelming, but with practice and a thorough understanding of the concepts, you will be able to tackle this exercise successfully. I recommend consulting with your instructor or classmates for further clarification and practicing with sample problems to build your confidence.

Lastly, thank you for pointing out the error in the code. I will make sure to inform the instructor about it so that it can be corrected.

Best of luck on your exam! You got this. Keep studying and asking questions when needed. That is the key to success in any scientific endeavor.