Affect of a Slow System to User Productivity

I am a consultant working with a company that has a user workflow that involves waiting about 12 minutes for the system to churn some data. That is, when a user needs to accomplish work item XYZ, the first step is to request the system to mash some data, and this process takes 12 minutes.

Additionally this process can fail with an exception message as much as 10-25% of the time. Sometimes the process can take noticeably longer than 12 minutes.

During the 12-minute download the browser page has a spinner up, and when the process ends the browser begins it's file-download process.

In my personal experience, such an imposition into a user's work flow is compounded enormously by the fact that 12-minutes is too long to sit there and wait. So what happens is users tend to go start working on something else, emails, or whatever. In my case anyway, I loose track of time and 45 minutes later I check back to find that my spinner is done, or worse, an exception occurred.

In other words, there's a breaking point at which a human being can no longer stay focused on a task and multitasking becomes almost compulsive, compounding the time-wasting effect of the slow system.

Is there any research on the effect that something like this has on productivity?

I'm looking for something that I can reference that quantifies how damaging this is to worker productivity. Additionally, knowing where the breaking point is would be very helpful. For example, for me a process of, say 2 minutes, would not be nearly as damaging to my workflow, and it becomes significantly more damaging as we increase the wait time from there.

This is my first UX post. I hope this is on-topic here. I did read the good question help page and I have done some internet searching on this topic without success (it is hard for Google to understand what I'm looking for in this case).