156 Chapter 3. Gas Filled Detectors
Figure 3.2.1: Variation of drift velocity of electrons in methane,
ethane, and ethylene (14).also be intuitively understood by noting that as the pressure of the gas increases the
density of the target atoms also increases, thus forcing an electron to make more
collisions along its track. Due to this dependence, many authors prefer to tabulate
or plot the electron drift velocities with respect to the ratio of electric field intensity
and pressure, that is,E/P. Such a curve is shown in Fig.3.2.4.