HP 5890 Series II Plus Reference Manual page 137

Detector Systems
Electron capture detector (ECD)
Figure 7-5
Electron Capture Detector (ECD)
The electron capture detector (ECD) cell contains
isotope emitting high•energyelectrons (
repeated collisions with carrier gas molecules, producing about 100
secondary electrons for each initial
Further collisions reduce energy of these electrons into the thermal
range. These low energy electrons are then captured by suitable sample
molecules, thus reducing total electron population within the cell.
Anode
63
Plated Ni Surface
Makeup Gas Adapter
y
Ni, a radioactive
µ
•particles).These undergo
µ
•particle.
Anode Purge
Vent
Nickel Plating
Fused Silica Liner
Makeup Gas
Column
137