In a sufficiently hard interaction between particles, 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)
**Abs ...
can be
factorized into
parton distribution functions (PDFs), the hard scattering part, and fragmentation functions. The fragmentation functions, as are the PDFs, are
non-perturbative
In mathematics and physics, a non-perturbative function or process is one that cannot be described by perturbation theory. An example is the function
: f(x) = e^,
which does not have a Taylor series at ''x'' = 0. Every coefficient of the Taylor ...
functions describing the production of a given observed final state. In a leading order picture, it can be interpreted as the probability that the observed final state originates from a given
quark
A quark () is a type of elementary particle and a fundamental constituent of matter. Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. All commonly o ...
or
gluon
A gluon ( ) is an elementary particle that acts as the exchange particle (or gauge boson) for the strong force between quarks. It is analogous to the exchange of photons in the electromagnetic force between two charged particles. Gluons bind q ...
.
See also
*
Proton structure function The structure function (also known as the proton structure function), like the fragmentation function, is a probability density function in physics. It is somewhat analogous to the structure factor in solid-state physics, and the form factor (quant ...
References
Functions related to probability distributions
{{particle-stub