This scene is the torus scene used for Figure 7 in "Progressive Photon Mapping" by Hachisuka et al. SIGGRAPH Asia 2008, and was modeled by Toshiya Hachisuka.

Permission to use the model/scene for non-commercial purposes is granted as long as proper credit is given. For example, put "The torus scene in Figure X is from Hackisuka et al. [2008] and was modeled by Toshiya Hachisuka." in the acknowledgement section of your paper.