https://indico.ihep.ac.cn//event/7614/

Maoqiang gives a introduction on lamda_c plus physics in BESIII, and measurement at 4 energy point are presented. Single tagged method is used to identify lamda_c plus and anti-lamda_c minus candidates in hadronic decay. Double tagged method is used afterwards. Then the ratio of DT yield and ST yield can be got and provide an absolute measurement of BF. Similar strategy is used for semi-leptonic decay case.

Kai shares some impressions after reading “Essentialism” recommended by Yuzhen. And we discuss on this issue, gaining much from it.

Minutes for today’s JC:

1. What’s the physical meaning of alpha_lamda_c?

It’s a shape parameter.

1. Ryuta: In the Figure 1, there are 4 red points from BESIII data, and the point at 4574.5 (most left one) shows bigger uncertainty in X-axis (sqrt(s)) direction, compared with the center two (4580.0, 4590.0) though the luminosity is much higher. Is there any specific reason for that ?

For Y-axis, sys. uncertainty contributes much. But for X-axis, we cannot know it well.

1. Xin: On page 5, it says “For signal events, Umiss is expected to peak around zero.” Could you explain why?

Because of the mass of neutrino 0.