Hi,
how did you solve the original linker error?
The current problem is a segmentation fault in betadecay::~betadecay(). That is typically a bug in memory/lifetime management in the user’s code. You can try compiling the application without optimizations (no -O compilation flags) and with debug symbols (-g compilation flag) to get better stacktraces: that will tell you exactly at what line the invalid memory access is happening.
Then you can also run the program within gdb to inspect the state of the program at the time it crashes.
Also please check out Posting code? Read this first! for instructions on how to post code. I edited your previous post to make it more readable.
Cheers,
Enrico