ABSTRACT
Helium (He) is an atomic gas, with atomic number 2 and electronic polarizability of 0228 × 10−40 F m2 and ionization potential of 24587 eV
See Table 31
Highlights of the cross section are
1 The cross section as a function of electron energy remains constant up to about 3 eV
2 For energy greater than about 10 eV, the cross section decreases monotonically
Due to the lowest number of electrons, the features of the cross section curve are different, particularly for energy <5 eV when compared with other target atoms or molecules See Table 32
Figure 32 shows the differential scattering cross sections as a function of energyFigure 33 shows the differential cross
31 Selected References for Data 19 32 Total Scattering Cross Section 19 33 Differential Scattering Cross Section 19 34 Elastic Scattering Cross Section 20 35 Momentum Transfer Cross Section 20 36 Energy Levels 21 37 Excitation Cross Sections 22 38 Ionization Cross Sections 22 39 Drift Velocity of Electrons 22 310 Mean Energy of Electrons 22 311 Reduced First Ionization Coefficients 23 312 Gas Constants 25 313 Ion Mobility 25 References 26
TABLE 3.1 Selected References for Data
Quantity Range: eV, (Td) Reference
Ionization cross section 25-1000 Rejoub et al. (2002) Total scattering cross section 10-3000 Zecca et al (2000)
Several cross sections 20-1000 Brusa et al (1996)
Total scattering cross section 05-220 SzmytKowski and Macia¸g (1996)
Excitation cross sections 25-500 Cartwright et al (1992)
Differential scattering 15-50 Brunger et al. (1992) Momentum transfer 0-700 Pack et al. (1992) Transport parameters (0001-100) Pack et al. (1992) Excitation cross section 30, 50, 100 Trajmar et al. (1992) Ionization cross section 25-1000 Krishnakumar and
Srivastava, (1988) Ionization cross section 25-1000 Lennon et al (1988)
Diffusion coeficient (565-5650) Al-Amin and Lucas (1987)
Excitation cross section 20-140 Mason and Newell (1987)
Ionization cross section 266-10000 Shah et al. (1987) Ionization cross section 20-200 Wetzel et al. (1987) Total scattering cross section 01-200 Buckman and
Lohmann (1986) Total scattering cross section 4-300 Nickel et al. (1985)
continued
sections as a function of scattering angle at selected electron energy
See Table 33
See Table 34
Selected References for D
Quantity Range: eV, (Td) Reference
Ionization cross section 26-750 Montague et al. (1984) Total scattering cross section 30-600 Kaupilla et al. (1981) Transport coefficients (1-850) Kücükarpaci et al.
