What happens when matter and antimatter collide?

1 Answer
May 29, 2018

Particle annihilation occurs and energy is released, typically as gamma radiation.


An example is an electron-positron annihilation:

Trond Saue, "Relativistic Hamiltonians for Chemistry: A Primer", ChemPhysChem 2011, 12, p. 3086

(Electron Zitterbewegung basically means a local fluctuation of the electron position.)

When these collide, each particle has mass #m_e = 9.10938356 xx 10^(-31) "kg"#. Conservation of particles, angular momentum, and energy is observed, and for the low-energy case, we write this process as:

#""_(-1)^(0) e + ""_(1)^(0) e -> 2""_(0)^(0) gamma#

The energy released is #m_ec^2# per particle, so the total energy released is

#E = 2m_ec^2 = 2 cdot 9.10938356 xx 10^(-31) "kg" cdot (2.99792458 xx 10^8 "m/s")^2#

#= 1.64 xx 10^(-13) "J"#

or about #"1.022 MeV"# (i.e. #"0.511 MeV/photon"#).