We utilize the effective field theory approach to study the properties of the axion. In particular, with s as well as u and d quarks regarded to be relatively light we derive a formula for the mass of the axion; a rou...We utilize the effective field theory approach to study the properties of the axion. In particular, with s as well as u and d quarks regarded to be relatively light we derive a formula for the mass of the axion; a rough estimate of the rate for its dominant decay mode at low energy is also carried out.展开更多
Bar graphs are convenient for showing comparisons among items．The bars may be either horizontal or vertical,and they are used to show the amounts of different items．Figure 1 is an example of a typical bar graph．The...Bar graphs are convenient for showing comparisons among items．The bars may be either horizontal or vertical,and they are used to show the amounts of different items．Figure 1 is an example of a typical bar graph．The graph shows the average sales price of existing homes in the Northeast United States for three years——1970,1980,and 1997．展开更多
Magazines and newspapers often display information using circle,bar,and line graphs．The following examples illustrate how estimation techniques can be applied to each of these graphs． Circle graphs,also called pie c...Magazines and newspapers often display information using circle,bar,and line graphs．The following examples illustrate how estimation techniques can be applied to each of these graphs． Circle graphs,also called pie charts,show how a whole quantity is divided into parts．展开更多
基金Supported by the National Natural Science Foundation of China under Grant No 11175088
文摘We utilize the effective field theory approach to study the properties of the axion. In particular, with s as well as u and d quarks regarded to be relatively light we derive a formula for the mass of the axion; a rough estimate of the rate for its dominant decay mode at low energy is also carried out.
文摘Bar graphs are convenient for showing comparisons among items．The bars may be either horizontal or vertical,and they are used to show the amounts of different items．Figure 1 is an example of a typical bar graph．The graph shows the average sales price of existing homes in the Northeast United States for three years——1970,1980,and 1997．
文摘Magazines and newspapers often display information using circle,bar,and line graphs．The following examples illustrate how estimation techniques can be applied to each of these graphs． Circle graphs,also called pie charts,show how a whole quantity is divided into parts．
