Hello World

Welcome to Hexo! This is your very first post. Check documentation for more info. If you get any problems when using Hexo, you can find the answer in troubleshooting or you can ask me on GitHub.

Quick Start

Create a new post

1
$ hexo new "My New Post"

More info: Writing

Run server

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$ hexo server

More info: Server

Generate static files

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$ hexo generate

More info: Generating

Deploy to remote sites

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$ hexo deploy

More info: Deployment

MathJax Test

在LHC上,我们可以简单计算一下它的对撞事例率:它的亮度恒定为
$$
L=10^{34}cm^{-2}s^{-1}
$$
$L=10^{34}cm^{-2}s^{-1}$

而非弹性散射的强子截面

$$\sigma(pp)\approx70mb$$

$\sigma(pp)\approx70mb$

因此它的对撞事例率为$7\times 10^8 Hz$。而束流管中的束团(bunches)每25ns对撞一次,因此每一次对撞的有效对撞事件就是$7\times2.5 = 17.5$。最后再考虑到束团的非饱和性(80\% of the available bunch spaces will be filled)。则每次对撞竟会同时产生17.5/0.8=22个事例,这就是事例堆叠(Pile up)。如何在这22次相同时间的对撞中正确挑选出来自同一个对撞的径迹和衰变粒子,这就需要我们对事例堆叠进行处理。

$$
\mu+
$$
J-PARC $\mu^+$