content_image/309619.jpg
charm and bottom R$_{AA}$ ( p$_{T}$ ) at $_{Lhc}$. 

<img src='content_image/309619.jpg'>

## 5.3 Double Ratio of charm to bottom R Q AA 

A disadvantage of the R Q $_{AA}$( p$_{T}$ ) observable alone is that its normalization and slow p$_{T}$ dependence can be fit with different model assumptions compensated by using very different medium parameters. In particular, high value ex- trapolations of the ˆ q parameter proposed in [435] could simulate the flat p$_{T}$ - independent prediction from AdS/CFT. 

We propose to use the double ratio of charm to bottom R$_{AA}$ to amplify the 

