Ionizing cylindrical column

It is also hard to believe that ion-electron recombination (IER) in the end part of the e+ track, which in [24] is assumed to be a cylindrical column of ionizations, precedes Ps formation. IER is related to much larger energy release (about amount of energy has to be eventually transferred to... 

Particle Tracks. Thus, irrespective of the particulate or photon nature of the primary radiation, the net effect is the formation of tracks consisting of ionized and excited molecules. These tracks, and their detailed structure can be revealed by the Cloud Chamber invented by Wilson in 1911(11). For fast electrons (low LET) the tracks mainly consist of spherical regions called spurs which contain from one to four ion-pairs which are separated in condensed phases by about 10 A. For more highly ionizing particles such as a-particles the tracks are essentially cylindrical columns of ionized and excited molecules. 

Figure 29.4, illustrates a schematic diagram of a flame-ionization detector. It comprises of a positively charged ring (also referred to as cylindrical collector electrode), whereas the flame jet serves as the negative electrode. The flame jet has two inlets from the bottom of the column effluent is introduced and from the side H2 to form the fuel, whereas air is let in uniformly around the base of the jet. 

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