Neutron flux
（重定向自Neutron flux density）
![](/Images/godic/202501/29/Neutron.svg5630.png")
The neutron flux is a quantity used in nuclear reactor physics corresponding to the total length travelled by all neutrons per unit time and volume, or nearly equivalently number of neutrons travelling through a unit area in unit time. The neutron fluence is defined as the neutron flux integrated over a certain time period.