Sticking coefficient of nitrogen on solid N2 at low temperatures

The sticking coefficient of nitrogen gas on a thick solid nitrogen film on a copper cold finger was studied at low temperature. For surface temperatures of about 12 Kthe sticking coefficient is measured to be 99.0 0.6%. Our result implies that itwill be possible to make a intense and high brightness slow positron source starting from a small diameter deposit of the gaseous positron emitter 13N2 produced in the reaction 12C(d,n)13N.