In its article medicalphysicsweb.org describes the results of a paper written by Lucas Burigo (DKFZ,FIAS), Igor Pshenichnov, Igor Mishustin, Marcus Bleicher (all FIAS) and Gerhard Hilgers (PTB Braunschweig)

The article descibes how  the scientists used the Geant4-based Monte Carlo model for heavy-ion therapy (MCHIT), developed at the Frankfurt Institute for Advanced Studies, to simulate track structures of various ionizing particles and shed light on the differences in biological effectiveness (Phys. Med. Biol. 61 3698).

"Cell survival after irradiation with ionizing radiation depends not only on the absorbed dose, but also on the radiation quality. Ion beams have a high linear energy transfer (LET) and greater relative biological effectiveness (RBE) than photons or protons, but no universal relation exists between LET and RBE for all radiation and cell types. As such, radiobiological studies are vital to establish connections between the radiation's physical quantities and its resulting biological effects." 

The full article can be reviewed at medicalpysicsweb.org. 

And the described paper under: Phys. Med. Biol. 61 3698

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