Sticking coefficient of nitrogen on solid N2 at low temperatures
نویسندگان
چکیده
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 K the sticking coefficient is measured to be 99.0 0.6%. Our result implies that it will be possible to make a intense and high brightness slow positron source starting from a small diameter deposit of the gaseous positron emitter N2 produced in the reaction C(d,n)N. # 2007 Elsevier B.V. All rights reserved. PACS : 67.70.+n; 68.43. h
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