An introduction about ILC(International Linear Collider) is given by Kiuchi Ryuta, including the generating of electron and positron, ring to main linac, accelerating, physical goal and detectors(SiD and ILD).

While Liu Kai uploaded slides on Gamma Conversion at BESIII, explaining

how it happens, how it is detected and its behavior at BESIII.

And there’re Q&A during the journal club uploaded by Zeng Hao:

Tao: Would lots of energy be lost at the corner (turn around) And how this effect would be compensated ?

Ryuta:Energy loss of e-(e+) by one circulation,the calculation result maybe is 0.1%.

Xin:Why ILC has to run in push-pull mode ?what is the main difference on the tracker between SiD &ILD ?

Ryuta:So far, I only found statements such like “we need cross-check and compete “

Maoqiang:What does “disk”means ?

Ryuta:There is a disk in the SiD detector,but no disk in ILD,you can see in the picture.

Maoqiang:Why dose the SiD have a disk, and the ILD have no disk?

Xin:Maybe for design considering.