Encyclopedia > Invariant mass

  Article Content

Invariant mass

In particle physics, the mathematical combination of a particle's energy and its momentum to give a value for the mass of the particle at rest. The invariant mass is the same for all frames of reference (see Relativity).

The invariant mass of a system of decay particles is related to the rest mass of the original particle by the following equation:

W2c4=(ΣE)2-(Σpc)2

where:

  • W is the invariant mass of the system of particles
  • ΣE is the sum of the energies of the particles
  • Σp is the vector sum of the momenta of the particles (includes both magnitude and direction of the momenta)
  • c is the speed of light



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Thomas a Kempis

... for a time in consequence of the pope's rejection of the bishop-elect of Utrecht, Rudolph of Diepholt; otherwise, Thomas' life was a quiet one, his time being ...

 
 
 
This page was created in 30.4 ms