How to directly output 208Pb/206Pb and error

chenhongjun

😃 Dear Bence and Joe，When I was processing the rutile U-Pb dating data recently, I found that my rutile does not contain Th, so it seems that it is more suitable to use 208 correction when correcting. According to the 208 correction formula without Th, the composition of common lead is estimated. f206=（208Pb/206Pb
）c/（208Pb/206Pb）m, So i want to know this value （208Pb/206Pb）m.
In addition, in common lead correction function that comes with the iolite software, the corrected age value output has no propagated error, only the corrected age value

Joe

chenhongjun

One way would be to create a 208/206 channel using the calculator (Tools menu/Calculator), e.g., Pb208/Pb206 = Pb208_CPS/Pb206_CPS. Then export the results for that channel as you would any other. You would only get the internal 2SE out, so would require a secondary reference material that you could evaluate the excess error with.

chenhongjun

Joe 😅 At present, I have obtained the corrected age of 206Pb-238U age through 207Pb correction and I can also see mean and error in the result window, but why the data after export only has mean instead of 2SE，I sent the file to your mailbox, and I also consulted other questions by the way, thank you

chenhongjun

Joe I follow your previous method to create a 208/206 channel using the calculator (Tools menu/Calculator), Name is Pb208/Pb206，Expression is Pb208/Pb206 = Pb208_CPS/Pb206_CPS，Type is output，But when I click calculate! button，A red × appears in the State column，And I don’t know where to save it

Joe

chenhongjun

I will need more information than that to go on. I tried doing a 207 correction in the 0207 apatite dataset you shared with support (not sure if that is the one you're referring to?) and the 207Pb-corr channels seem to export fine including the mean and 2SE. How are you trying to export the data? Are you using the normal export to file method, the PlasmAge script, or something else? Are there no columns for the 2SE, blank values, or something else?

chenhongjun

Joe 😀 Thank you very much, Joe, I just checked it. Yesterday the file didn’t seem to be sent out, but it didn’t affect my problem. All my data has the same problem, that is, I can’t output 2SE corresponding to 207Pb-corr channels.i was using the normal export to file method and there are no columns for the 2SE，I will send you emails and screenshots later, screenshots here are not convenient

Joe

chenhongjun

I believe the reason you're not seeing any 2SE output for the 207Pb-corr channels is that you are only selecting propagated 2SE for the export. Since those channels do not have a propagated error no column is written for the error. You could select basic and propagated error for the export. This will output the internal 2SE and propagated 2SE (for channels that have that information).

Is it possible you're trying to run that calculator routine before running the U-Pb DRS? If the _CPS channels have not been calculated yet by a DRS the calculator routine will fail. You do not necessarily need to save it, but if you want to, you can save it anywhere.

chenhongjun

Joe 😆 Yes, I chose both basic and propagated error for the export, and successfully output the internal 2SE and propagated 2SE , but why there is only internal 2SE in the 207Pb-correct age channel and no propagated 2SE？