a question about notation

rbwang1225

Hello, I am reading the paper "Covariant Action for a D=11 Five-Brane with the Chiral Field".
I don't understand the [itex](\partial a)^2[/itex] in the dual field strength [itex]\widetilde{F}_{mn}\equiv\frac{1}{\sqrt {(\partial a)^2}}F^*_{mnl}\partial^la(x)[/itex].
Is it ##\partial_ra\partial^ra##?

Regards.

Einj

Yes, I think that could be correct.

rbwang1225

ok, thank you!