Total Cross Sections for Ionization and Attachment in Gases by Electron Impact. II. Negative-Ion Formation

Absolute total cross sections for negative-ion formation in several gases (CO, NO, O2, CO2, N2O, SF6, and H2) by electron impact have been measured in a total ionization tube. Both dissociative attachment and ion-pair formation have been measured, with careful attention paid to complete collection of the negative ions. Possible errors due to scattered electrons and energy spread are discussed.