Cover News

Dark Matter - The Mysterious Ghost in The Universe

On the evening of September 24th, 2016, the 14th lecture of Tsinghua Astrophysics Public Series (TAPS): New Worlds, New Horizons was held at the Auditorium. The speaker, Professor Xiangdong Ji is the director of Institute of Nuclear, Particle, Astronomy and Cosmology (INPAC) at Shanghai Jiao Tong University (STJU), and is the project leader for the PandaX experiment located in the China Jin-Ping underground Laboratory (CJPL). Approximately 1,000 students, faculties and off-campus audience attended the lecture.


Low Temperature Detector Lab near completion

Two large rooms on the 6th floor of the Meng Min Wei Building have been renovated and set up as the new Low Temperature Detector Lab. The construction is now nearly completed. The lab will be used by Prof. Wei Cui’s group to develop superconducting transition-edge sensor (TES) arrays for high throughput, high resolution X-ray imaging spectroscopy in astrophysics. A TES operates as an ultra-sensitive thermometer. It measures the deposited energy of an incident X-ray photon by sensing a tiny rise in the temperature of the absorber (to which it is attached). The absorber temperature recovers, after heat leaks out (to a thermal bath), and the detector is ready for another photon. The accuracy to which a TES measures photon energy is fundamentally limited by thermodynamic fluctuations in the exchange of thermal energy between the absorber and the thermal bath. To achieve good energy resolution, it is necessary to operate the device at cryogenic temperatures (typically < 100 mK).