Using IF function to create a date

Hello,
I am trying to create a cell that shows todays date if another cell has a particular value.

The formula I am currently using is:
IF(E9=L,TODAY) where L refers to whether a project is live or not. If the project is live, I want the cell to show todays date so I can then use DATEDIF in another cell to show the number of days the project has been live for.
I have tried various differnt versions and either I have too many or too few arguments. I just want it to remain blank if the argument is false.

Thanks