In
scattering theory
In mathematics and physics, scattering theory is a framework for studying and understanding the scattering of waves and particles. Wave scattering corresponds to the collision and scattering of a wave with some material object, for instance su ...
and
accelerator physics, luminosity (''L'') is the ratio of the number of
events detected (''dN'') in a certain period of time (''dt'') to the
cross-section
Cross section may refer to:
* Cross section (geometry)
** Cross-sectional views in architecture & engineering 3D
*Cross section (geology)
* Cross section (electronics)
* Radar cross section, measure of detectability
* Cross section (physics)
**Ab ...
(''σ''):
[
]
:
It has the dimensions of events per time per area, and is usually expressed in the
cgs units of
cm−2·
s−1 or the
non-SI units of
b−1·s
−1. In practice, ''L'' is dependent on the
particle beam parameters, such as beam width and particle flow rate, as well as the target properties, such as target size and density.
[
A related quantity is integrated luminosity (''L''int), which is the ]integral
In mathematics, an integral assigns numbers to functions in a way that describes displacement, area, volume, and other concepts that arise by combining infinitesimal data. The process of finding integrals is called integration. Along with ...
of the luminosity with respect to time:[
:
The luminosity and integrated luminosity are useful values to characterize the performance of a ]particle accelerator
A particle accelerator is a machine that uses electromagnetic fields to propel electric charge, charged particles to very high speeds and energies, and to contain them in well-defined particle beam, beams.
Large accelerators are used for fun ...
. In particular, all collider experiments aim to maximize their integrated luminosities, as the higher the integrated luminosity, the more data is available to analyze.[
]
Examples of collider luminosity
Here are a few examples of the luminosity of certain accelerators.[
]
References
Accelerator physics
Scattering theory