Hi Chao,
Thanks for your question.
Yes, you are correct, the units of absorbed energy AOfRhoAndZ are [1/mm^3].
AOfRhoAndZ is a detector that talies absorbed energy in cylindrical coordinates (rho,z). Within the infile specification for this detector, the rho and z bins can be defined. In our sample infile infile_one_layer_all_detectors.txt we give example inputs for all detectors including AOfRhoAndZ. We also have a AOfXAndYAndZ detector which is absorbed energy in Cartesian coordinates.
Let me know if you have any further questions.
Best,
Carole