What is the parent of Xenon 133?

[youngdogs]

I'm a nuclear medical student and am studying the radiopharmaceutical Xenon 133. I know that Xenon 133 decays into Cerium 133, but what is Xenon 133s direct parent? (I believe Xenon 133 is in the Uraninum 235 decay scheme.)

Thank you in advance for your help.

 

[Bill_K]

The logical parent of ¹³³Xe in an alpha decay chain would be ¹³⁷Ba, having two more protons and two more neutrons. However ¹³⁷Ba is stable.

In fact ¹³³Xe is a fission product of ²³⁵U, and is a waste produced by nuclear reactors. A large quantity was http://www.nuc.berkeley.edu/node/5844 in the Fukushima earthquake disaster.

 

[Vanadium 50]

It's a fission product, as Bill said. It's also an I-133 daughter, and I-133 is also a fission product. Heavy element decay chains do not typically go as far as 133.

 

[youngdogs]

I appreciate your responses. Thank you for your help.