# Number of electron-positron pairs/sec out of Al converte

## LINAC parameters used in calculations

1) pulse width 50 ps
2) pulse current 50 A
3) repetition rate 300 Hz
4) energy 44 MeV

## Number of photons/sec out of radiator






Alex factor is 6.85 %




## Pair production rate

### out of Al converter



 (by varying width we can vary the yield)






### through 1 m of air










## Appendix

### pair production cross sections in an Al target

Geant4 and Theoretical Pair Production Cross Sections for 1 MeV - 100 GeV photons in Aluminum. Vakho Makarashvili, December 18, 2007