find a reason why asp application ended

when my aspx is called it kills the application. The page is loades with out any errors.
but at the end  "void Application_End(object sender, EventArgs e)" method of global.asax file is called and the session is also ended.
i want to know what ended the application. how to know which part of the page has ended the application and why session got terminated. 


is there a way to see the list of processes to identify the process that killed the application
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