Radioactive decays, different modes share

[taffer33]

Hello,

I'd like someone to help me understand, how can I tell from available data, what is the approximate share of different decay modes, for some given nuclide activity.

Let's take 90Y for instance. It's known for being beta-emitter, but it emits gammas and X-rays as well. How to approximately assess what is the number of registered emitted electrons and number of emitted gamma quantum, let's say during one hour of active isotope. What will be the percentage of beta and gamma from given activity?

For example
https://www.nndc.bnl.gov/chart/decaysearchdirect.jsp?nuc=90Y&unc=nds

From this data I can see there are two ways of Y-90 decaying, beta minus and gamma IT. I can read the intensities for given decay modes. From the IT decay we have gammas 202,53 keV (97%) and 479,51 keV (90,7%). From the beta - almost 100% of the electrons with initial energy of 933 keV.

And now my problem is to understand this part. I have 100% intensities for one decay mode, and 100% for the another - and how can I find the information which mode is more probable to occur?

 

[mathman]

There are two isomers of Y-90 called Y-90 and Y-90m. Your two modes are one for each isomer. I can't find more information.

 

[mfb]

If there is more than one decay mode you need a database that gives their relative frequencies. In this case you are comparing two different things, however.