Understanding QFT Notation: Delta Function and Statistical View

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\delta^{\left(d\right)}\left(\b{q}-\b{q}\prime \right)

from Quantum Field theory and Critical Phenomena by Justin.. (the text covers QFT from a statistical view)

Question: what does the d in brackets mean/do ?

Thanks =)
 
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this is mainly a quess but I think it could be the dimension of the delta function ie if d=3 the the q-vectors are 3 component vectors. I think I've seen such notation used somewhere.
 
I've seen it in BRST, so i also think it may mean the dimension of space(time).

Daniel.
 
lol can't be bothered with latex at the mo, but yeah I asked someone in my office and they said it meant that function multiplied together d times but in terms of the dimensional components
 
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