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From the definition of a fragmentation function we have that 

where we get to the last line by employing Eq. (B.2) twice. 

## B.2 Partonic R Q AA 

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For in-medium momentum loss in which the final momentum is related to the initial momentum by p$_{f}$ = (1 − ϵ ) p$_{i}$ we have the probability of fractional energy loss for parton q with initial momentum p$_{i}$ is P$_{q}$ ( ϵ | p$_{i}$ ). Then, exactly as for fragmentation functions (Eq. (B.4)), 

where we have suppressed the q index on P , and hence (Eq. (B.5)) 

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If we assume that the production spectrum can be approximated by a 

