AMOC relief and lineshape function

Since both 511 keV photons resulting from a 2y-annihilation event transmit equivalent information, one photon may be used to determine the age of the annihilating positron and the other for the correlated measurement of the momentum of the annihilating positron-electron pair by measurement of the 

Doppler shift of the photon energy. Data acquisition is performed by a two-parameter multichannel analyzer [1-4], 

In order to take advantage of the full information contained in the AMOC data we use a two-dimensional fitting procedure A two-dimensional model function representing the number of counts as a function of positron age and energy of the annihilation quanta is fitted to the raw AMOC relief without prior data reduction. On the age axis, each positron state is represented by an exponential decay function convoluted with the time resolution function of 

The mean kinetic energies of annihilating electrons may provide information on the electronic surroundings where the positrons undergo annihilation. 

Tj =1/A,i Lifetime (inverse of annihilation rate) of the positron state i 

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