Is there a parameter controlling the width/thickness of axis ticks?

This is probably a trivial problem. I know the “length” of the ticks can be changed by the parameter “MAP_TICK_LENGTH_PRIMARY”, but it seems the width cannot be changed in a similar way?

I asked this because when plotting many small subplots together, I prefer to use thinner frame, then the ticks become a bit too thick:

Just for aesthetic purposes…

How about MAP_TICK_PEN?

Thank you! It works!