There are few things that particle physicists like to talk about more than luminosity (know affectionately as “L”). We measure it obsessively, we boast about it shamelessly and we never forget to mention it in our papers, plots and talks. So what’s the big deal? What is luminosity and why is it important?
The concept of instantaneous luminosity is borrowed from the field of astrophysics, and in that field it’s used to describe how much energy a star gives off. To calculate the instantaneous luminosity, simple measure how much energy flows through a surface in an interval of time. To get the instantaneous luminosity in particle physics simply swap energy for the number of particles and the definition is the same!