August 20th, 2011, Professor Michael L. Cherry, chair of the Department of Physics and Astronomy, Louisiana State University paid a formal visit to Purple Mountain Observatory. Dr. YANG Ji, director of PMO hosted the receiving meeting.

Vice chair Dr.  GAN Weiqun　briefed Dr. Cherry about the history and current situation of PMO, mainly introduced to him the key researches here under going at PMO. Dr. YANG Ji , Dr. CHANG Jin, and Dr. Cherry had extensive communication regarding the deep-field exploration and high-energy detection projects. They also had preliminary discussion about possible cooperation in the future.

Accompanied by Dr. CHANG Jin, Cherry looked around the key laboratory of Dark Matter and Space Astronomy, PMO, saw the latest development of the Dark Matter Particle Detector.