I am a master student in Nanjing University, China. My major is in high energy physics. I worked both at Nanjing University and IHEP. There I got some basic knowledge and skills for HEP experiment, such as quantum field theory and ROOT. 

I received the email of summer student program from my supervisor, it was at the end of February near the deadline. I filled those forms really in a rush, and finally caught the deadline. I should thank my both supervisor Prof. Qi and Dr. Fang, they helped me a lot when I was confused my forms. I am so happy that CERN gives me such a chance when I received the email saying I can come. 

After several months waiting and preparing I arrived at CERN at 7th July and started my summer student program with Christopher Young in SUSY group on ATLAS. 

My project is Multijet tau background study. t while searching for the lightest SUSY particle, the main and most complex background is tau decay. We need a very high cut efficiency to make sure we don’t lose too much signal jets while reject as much as possible tau background. My work is focus on the tau decay mode of one track, because we have already done a lot of work on tau decays to jet with 3 tracks. With the help of my supervisor, I am trying to make cuts on different variables which are sensitive to taus. By doing cuts on 2D plots or higher dimensions or even maybe with a BDT, we hope we can reach the efficiency we need. I also wish that I can get the result before I leave. If I cannot I really like to work for several weeks more for it to get a better result before I come back to continue my master project. 

The pace of studying and working at CERN is very nice. In the morning we are attending the lectures, then working on our projects during the afternoon then having fun and discuss things with friends in the evening. It is quite different from my home institute that I can get the idea from people all over the world. 

For me it has been a great opportunity to be here. From my time as a summer student at CERN I will remember the lectures, not only the stuff we learnt but also the brief and overall idea that we got about the LHC and HEP. Moreover, I will remember my colleagues who helpem me in solving problems but also joining me to get some fun. 

I will never forget my summer as a summer student at CERN. It was one of the most enjoyfull summers of my life!