How to create a concurrent thread group where a given concurrent users hit only once in given elapsed time?

I need to make a concurrent thread group where the given number of concurrent users should hit only once, what happening now is that in a given period of time, it is hitting multiple times. See graph.

The concurrency thread graph is like this, what I want is 0-1 seconds, concurrent users are continuously hitting. I want concurrent users to hit once only. Graph should be like this.

I want a graph like this. All concurrent users should hit once and then, that's it