Electronic and Ionic Impact Phenomena IV

Title page ......Page 1
Date-line ......Page 2
PREFACE TO THE SECOND EDITION ......Page 3
PREFACE TO THE FIRST EDITION ......Page 7
ACKNOWLEDGEMENTS for VOLUME IV ......Page 9
CONTENTS ......Page 11
1. Introduction ......Page 25
2. Electron-ion recombination ......Page 26
2.1. Radiative recombination ......Page 27
2.2. Recombination through inverse autoionization ......Page 28
2.2.1. Dielectronic recombination ......Page 29
2.2.2. Dissociative recombination ......Page 32
2.3.1. Simplified theory ......Page 36
2.3.2. Detailed theory ......Page 40
2.3.3. Effect of optical thickness ......Page 44
2.3.6. Inclusion of dielectronic recombination ......Page 46
2.3.7. The energy balance in a decaying plasma ......Page 50
2.3.8. Collisional-dissociative recombination ......Page 57
2.4. Neutral collisional-radiative recombination ......Page 59
3. Experimental methods for investigating electron-ion recombination ......Page 65
3.1.1. Microwave probing methods—general principles ......Page 66
3.1.2. Microwave probing methods—typical experiments ......Page 73
3.1.3. Use of single Langmuir probes ......Page 77
3.1.4. Use of a double probe ......Page 79
3.1.5. Study of afterglows in shock-excited gas ......Page 84
3.1.6. Measurement of relaxation times in caesium-seeded plasmas ......Page 88
3.1.7. Optical experiments ......Page 89
3.1.7.1. Spectroscopic study of line and band emission in flowing afterglows ......Page 90
3.1.7.2. Spectroscopic study of line and band emission in static afterglows ......Page 92
3.1.7.3. Experiments with an arc-jet plasma ......Page 94
3.1.7.4. Interferometric study of the widths and profiles of afterglow lines ......Page 96
3.1.8. Recombination in flames ......Page 100
3.1.9. Merging-beam methods ......Page 104
4.1. Historical account ......Page 106
4.2. Recombination in helium ......Page 111
4.2.1. Experiments in dense plasmas ......Page 114
4.2.2. The origin of the He2 band emission in an afterglow ......Page 123
4.2.3. Recombination in helium at higher pressures—possible contribution from He3+ ......Page 130
4.2.4. Concluding remarks—the He2 potential-energy curves ......Page 132
4.3.1. Neon ......Page 133
4.3.1.1. Temperature variation of the recombination coefficient ......Page 141
4.3.2. Argon ......Page 143
4.3.3. Krypton and xenon ......Page 145
4.4. Recombination in caesium and caesium-seeded plasmas ......Page 147
4.5. Recombination in nitrogen ......Page 151
4.6. Recombination in oxygen ......Page 158
4.7. Recombination in nitric oxide ......Page 161
4.8. Recombination in hydrogen ......Page 164
4.9. Recombination in carbon dioxide ......Page 166
4.10. Neutral collisional-radiative recombination in flames ......Page 167
5.3. Mutual neutralization ......Page 169
5.4. Three-body recombination ......Page 176
5.4.1. J. J. Thomson's theory ......Page 177
5.4.2. Application of collisional-recombination theory ......Page 180
5.4.3. Langevin's theory ......Page 185
5.5.1. The medium-pressure range ......Page 186
5.5.2. The high-pressure region ......Page 190
5.6.1. Experiments using a photoionization source ......Page 191
5.6.2. Measurement of mutual neutralization rates using the dielectric-constant method ......Page 196
5.6.3. Application of the merging-beam technique to the measurement of rates of mutual neutralization ......Page 199
6.1. Introduction—the ionosphere ......Page 202
6.2. Observational methods for exploring the ionosphere and the data obtained ......Page 204
6.3. Observational methods for observing solar radiation and atmospheric composition ......Page 205
6.4. Determination of relevant reaction rates ......Page 207
6.5. Application to the ionosphere in the E and F$_1$ regions ......Page 208
6.6. The F$_2$ region ......Page 211
6.7. The exosphere ......Page 212
6.8. The lower ionosphere ......Page 213
21. COLLISION PROCESSES INVOLVING ENERGETIC IONIZED AND NEUTRAL BEAMS OF ATOMS AND MOLECULES—INTRODUCTION ......Page 216
1. Experiments with ionized atomic beams ......Page 217
2. Relative (C.M.) and laboratory coordinates ......Page 220
3. Notation for cross-sections ......Page 221
4.1. Ion sources ......Page 222
4.2. Neutral atom sources ......Page 232
5.1. The Faraday cage ......Page 234
5.2. Thermal detectors ......Page 235
5.3. Secondary emission detectors ......Page 236
5.4. Scintillation counters ......Page 237
5.6. Solid-state counters ......Page 238
6.1. Photon detectors ......Page 239
6.2. Calibration of photon detectors ......Page 241
7.1. Beam and static gas target configuration ......Page 243
7.2. Intersecting beams ......Page 245
1. Introductory remarks ......Page 247
2. The principles involved in the measurement of' total' scattering and the analysis of the data obtained ......Page 250
3.1. The experimental arrangements ......Page 256
3.2.1. He-He collisions ......Page 263
3.2.2. Collisions between other neutral atoms in their ground states ......Page 268
3.2.3. Collisions involving diatomic or polyatomic molecules ......Page 272
4.1. The experimental arrangements ......Page 277
4.1.1. The measurement of'total'cross-sections ......Page 278
4.1.2. The measurement of differential cross-sections ......Page 283
4.2.1. The interaction potential in the ground state ......Page 291
4.2.2. The inversion problem ......Page 294
4.2.3. Use of impact expansions ......Page 296
4.2.4. Interaction between elastic and inelastic collisions—perturbation due to curve crossing ......Page 298
4.2.5. The inelastic scattering due to a pseudo-curve crossing ......Page 302
4.2.7. Summary of possibilities arising from analysis of perturbations ......Page 305
4.3.1. He+-Ne collisions ......Page 306
4.3.1.2. Pseudo-crossing perturbations ......Page 309
4.3.2. Ne+-He collisions ......Page 315
4.3.3. He+-Ar collisions ......Page 316
4.3.4. He+-Kr and He+-Xe collisions ......Page 320
4.3.5. H+ collisions with Ar, Kr, and Xe ......Page 322
4.3.6. Li+-He collisions ......Page 323
4.3.7. Li+ collisions with H2, N2, and 02 ......Page 327
4.3.8. Other collisions between ions and neutral atoms or molecules ......Page 328
1. Introduction ......Page 329
2.1.1. Summary of formulae ......Page 330
2.1.3. Excitation and ionization of helium atoms ......Page 333
2.1.4. Ionization of outer shells of complex atoms ......Page 339
2.1.5. Inner shell ionization ......Page 340
2.2.1. Collisions between normal H atoms ......Page 344
2.2.3. He+-H collisions ......Page 350
2.2.4. H-He collisions ......Page 352
2.2.5. He+-He collisions ......Page 357
2.2.7. Detachment of electrons from H- ......Page 358
2.2.8. Other collisions ......Page 359
3. Fast collisions—electron transfer reactions ......Page 361
3.1.1. Born's approximation ......Page 362
3.1.2. The non-orthogonality problem—Bates's approximation ......Page 364
3.1.3. Behaviour of the cross-section for symmetrical charge exchange at very high energy ......Page 368
3.1.4. The impulse approximation ......Page 372
3.2.1. H+-H collisions ......Page 376
3.2.3. H+-He collisions ......Page 377
3.2.4. H+-O and H+-N collisions ......Page 380
3.2.5. Semi-empirical theory of the capture of electrons by protons from many-electron atoms ......Page 383
3.2.6. Relation of capture cross-sections from molecules to those for the constituent atoms ......Page 384
3.2.7. H-H collisions ......Page 387
3.2.8. He+-He collisions ......Page 388
3.3. Excitation of triplet states of helium by hydrogen atom impact ......Page 389
3.5. 'Capture' into continuum states ......Page 393
4.2.1. Application of the Monte Carlo method ......Page 395
4.2.2. The classical impulse approximation—conditions for validity ......Page 398
4.2.3. The classical impulse approximation—application to H+-H collisions ......Page 401
4.3.1. Some classical dynamical formulae ......Page 404
4.3.2. Application to electron loss by neutral atoms in passing through gases ......Page 408
4.3.3. Application to detachment of electrons from H- ions in passing through gases ......Page 413
4.4. Classical treatment of charge transfer in terms of binary encounters ......Page 414
4.4.1. High velocity encounters ......Page 415
4.4.2. Electron capture by protons from heavy atoms ......Page 417
5.1.1. By proton impact ......Page 420
5.1.2. By impact with other atoms and molecules—total cross-sections ......Page 424
5.1.3. By impact with other atoms and molecules—angular distributions of dissociation products ......Page 427
5.2. Collisions involving complex ions and molecules ......Page 431
6. Slow collisions—symmetrical charge transfer ......Page 436
6.1.1. Introductory theory—the total cross-section for charge transfer ......Page 437
6.1.2. The differential cross-sections for elastic scattering and charge transfer ......Page 440
6.1.3. The effect of nuclear symmetry ......Page 443
6.1.4. The effect of the transfer of the electron momentum ......Page 444
6.1.5. The effect of transitions to states which dissociate into excited H atoms ......Page 447
6.1.6. Results of calculations—the total cross-section for charge transfer ......Page 451
6.1.7. Results of calculations—differential cross-sections ......Page 453
6.2.1. The interactions effective in producing charge exchange ......Page 456
6.2.2. Angular distribution of scattered He+ ions ......Page 459
6.3. He++-He collisions ......Page 470
6.4. Ne+-Ne and Ar+-Ar ......Page 474
6.5. Li+-Li ......Page 483
6.6. Hg+-Hg ......Page 486
6.7. H--H ......Page 487
6.9. H2+-H2 collisions ......Page 489
6.10. Semi-empirical formulae—relation of charge transfer cross-section to ionic mobility ......Page 491
6.11. Classical theory and slow, symmetrical, charge transfer collisions ......Page 493
7.1.1. Wave formulation ......Page 495
7.1.2. Impact parameter formulation ......Page 500
7.1.3. Born and distorted wave approximations ......Page 501
7.2. Strong coupling without distortion—schematic model ......Page 502
7.3. Application of other methods for solving the coupled equations ......Page 505
7.4. Charge transfer between multiply-charged ions and atoms — long range crossing ......Page 507
8.1. Introduction—classification of approximations ......Page 511
8.2. H+-H collisions ......Page 517
8.2.1.1. Inclusion of distortion ......Page 518
8.2.1.3. Harmonic expansion method ......Page 519
8.2.1.5. Use of Sturmian expansion ......Page 521
8.2.1.6. Back coupling and coupling through intermediate states—use of a time-dependent effective nuclear charge ......Page 522
8.2.1.7. Use of a pseudo-state expansion ......Page 523
8.2.2.1. Symmetrical charge transfer ......Page 525
8.2.2.2. 2s and 2p excitations with and without charge transfer ......Page 526
8.4.1. Excitation ......Page 531
8.4.2. Charge transfer ......Page 535
8.5. He++-H collisions ......Page 539
8.6.1. Calculations ignoring electron exchange ......Page 541
8.6.2. Inclusion of electron exchange ......Page 544
8.7. H-He collisions ......Page 546
9. Ionizing collisions between atomic systems at slow to intermediate energies ......Page 547
1. Experimental methods ......Page 552
1.1.1. Primary particles ......Page 553
1.1.2. Secondary ions ......Page 555
1.1.3. Electrons ......Page 557
1.1.4. Coincidence studies ......Page 560
1.2.1.1. Basis of the experimental approach ......Page 564
1.2.1.2. The condenser plate method ......Page 566
1.2.1.3. Methods used in collisions involving low energy-ion beams ......Page 573
1.2.1.4.1. Measurements at keV energies ......Page 578
1.2.1.4.2. Measurements at low impact energies ......Page 584
1.2.2.1. Single collision methods ......Page 590
1.2.2.2. Charge equilibration of fast particle beams in thick gaseous targets ......Page 602
1.2.2.3. Beam attenuation studies ......Page 608
1.2.2.4. Growth curve methods ......Page 613
1.2.2.5. The Aston band method ......Page 614
1.2.3. Studies of the effect of an excited state population in the primary beam ......Page 617
1.2.4.1. Crossed beams ......Page 622
1.2.4.2. Merging beams ......Page 628
1.2.4.3. Inclined beams ......Page 632
1.3.1. Introduction ......Page 635
1.3.2.1. Experimental arrangements ......Page 636
1.3.2.2. Derivation of the inner shell ionization cross-section ......Page 639
1.3.3. Measurement from observation of Auger electron emission ......Page 640
2.1.1. Primary and secondary collision products—general description ......Page 642
2.1.2. Angular distribution of scattered primary particles ......Page 643
2.1.3. Energy and angular distribution of the scattered secondary ions ......Page 649
2.1.4. Coincidence studies and inelastic energy loss ......Page 651
2.1.5. Energy and angular distribution of the electrons emitted in inelastic collisions ......Page 666
2.2.2.1. H+-H ......Page 677
2.2.2.3. Reactions involving neutral and singly ionized rare-gas atoms ......Page 680
2.2.2.5. Reactions involving alkali-metal atoms ......Page 684
2.2.2.6. Reactions involving O, N, and C atoms ......Page 689
2.2.2.7. Reactions involving doubly and triply ionized rare-gas atoms ......Page 691
2.2.2.8. H2+-H2 ......Page 692
2.2.3. Simple charge transfer—accidental resonance ......Page 694
2.2.4. Simple charge transfer at low impact energies—non-resonant cases—total cross-sections ......Page 698
2.2.4.1. Charge transfer reactions involving H+ ......Page 699
2.2.4.2. Charge transfer reactions involving He+ ......Page 702
2.2.4.3. Charge transfer reactions involving heavier rare-gas ions ......Page 705
2.2.4.4. Charge transfer reactions involving alkali-metal ions and atoms ......Page 706
2.2.4.6. Other single electron capture reactions involving singly-charged positive ions ......Page 709
2.2.4.8. Charge transfer reactions involving negative ions ......Page 710
2.2.5. Simple charge transfer at low impact energies—mutual neutralization ......Page 714
2.2.6.1. Total cross-sections ......Page 715
2.2.6.2. Energy distribution of detached electrons ......Page 721
2.2.7. Ion-atom interchange ......Page 724
2.2.8.1. Collisions in atomic hydrogen ......Page 733
2.2.8.2. Collisions in other gases ......Page 737
2.2.8.3. H- formation ......Page 746
2.2.8.4. Collisional destruction of H(2s) atoms ......Page 747
2.2.9. Charge-changing collisions involving fast helium beams ......Page 751
2.2.9.1. He+ beams ......Page 752
2.2.9.2. He0 beams ......Page 756
2.2.9.3. He++ beams ......Page 758
2.2.9.4. He- production ......Page 760
2.2.10.1. Atoms of the first long row of the periodic table ......Page 762
2.2.10.2. Heavy metal atoms and ions ......Page 771
2.2.10.3. Bromine and iodine atoms and ions ......Page 773
2.2.10.4. Production of long-lived excited ions ......Page 776
2.2.11.1. Introduction ......Page 781
2.2.11.2. H+-H collisions ......Page 785
2.2.11.3. He+-He collisions ......Page 790
2.2.11.4. Ne+-Ne collisions ......Page 796
2.2.11.5. Ar+-Ar collisions ......Page 801
2.2.11.6. Other symmetrical collisions involving singly-charged positive ions ......Page 802
2.2.11.7. He++-He collisions ......Page 803
2.2.11.8. H--H collisions ......Page 805
2.2.12. Differential scattering in charge-changing collisions — probability of charge transfer in non-symmetrical cases ......Page 806
2.2.12.2. He+-H collisions, ......Page 807
2.2.12.4. Other collisions involving He+ ......Page 808
2.2.12.5. Collisions involving other singly-charged ions ......Page 809
2.2.12.6. H-H and H-H2 collisions ......Page 811
2.2.12.7. He++-H collisions ......Page 812
2.2.12.8. Collisions involving other multiply-charged ions ......Page 813
2.2.13.1. Dissociation of H2+ — total cross-sections ......Page 819
2.2.13.2. Dissociation of H2+ — energy and angular distribution of product protons ......Page 826
2.2.13.3. Dissociation of other fast molecular ions ......Page 844
2.3.1.1. Ionization by fast hydrogen beams ......Page 846
2.3.1.2. Ionization by fast helium beams ......Page 851
2.3.1.3. Ionization by fast beams of species other than hydrogen or helium ......Page 857
2.3.1.4. Ionization at low impact energies ......Page 861
2.3.2.1. Multiple ionization of atomic targets ......Page 867
2.3.2.2. Ionization and fragmentation of molecular targets ......Page 870
2.3.3.2. Ionization by He+ ions ......Page 876
2.3.3.3. Dependence of inner shell ionization cross-sections on the atomic number of the target ......Page 882
2.3.3.4. Ionization by heavier ions ......Page 883
2.3.3.5. Dependence of inner shell ionization cross-section on impact parameter in the ionizing collision ......Page 885
2.3.3.6. Results obtained from observations of Auger emission ......Page 888
2.3.3.7. Comparison with theory ......Page 890
2.3.3.8. Interpretation of anomalous inner shell excitation by heavy incident ions ......Page 892
3. Comparison of theory and experiment for charge-changing and ionizing collisions—summary account ......Page 895
3.1.1. H+-H collisions ......Page 896
3.1.2. He++-H collisions ......Page 898
3.2.1. H(1s)-H(1s) and H+-H- collisions ......Page 899
3.2.3. H+-He and He+-H collisions ......Page 900
3.2.4. He++-He collisions ......Page 901
3.3.1. He+-He collisions ......Page 902
3.3.2. H--H collisions ......Page 903
3.3.4. H(1s)-He(1^1S) collisions ......Page 904
3.5. Collisions between more complex systems and general summary ......Page 905
3.5.1. Ionization and detachment ......Page 906
3.5.2. Charge transfer and elastic scattering ......Page 908
3.6. Concluding remarks ......Page 911
1.1.1. Basis of the experimental approach ......Page 913
1.1.2. General experimental requirements for the accurate determination of emission functions ......Page 914
1.1.3. Measurements with static gas targets ......Page 917
1.1.4. Crossed beam measurements ......Page 920
1.1.5. The photon-coincidence method ......Page 923
1.2.1. The decay curve method ......Page 925
1.2.2. Metastable states—the beam attenuation technique ......Page 926
1.2.3. Metastable states—analysis by electric field quenching ......Page 927
1.2.4. Highly excited states—field ionization methods ......Page 930
2.1. Introduction—the earlier observations ......Page 933
2.2.1.1. Emission due to excitation of H atoms in a beam ......Page 937
2.2.1.2. Emission due to impact by protons in atomic gases ......Page 943
2.2.1.3. Emission due to impact by protons on molecular gases ......Page 951
2.2.1.4. Emission in He+-H impacts ......Page 955
2.2.1.6. Emission due to impact of H2+ and D2+ ions with rare gases ......Page 956
2.2.2.1. Excitation by proton beams ......Page 958
2.2.2.2. Excitation by H atom beams ......Page 967
2.2.2.3. Excitation by He+ ion beams ......Page 970
2.2.3. Excitation of the heavier rare gases ......Page 975
2.2.4. Excitation of molecular gases ......Page 979
2.2.4.1. Excitation of H2 ......Page 980
2.2.4.2. Excitation of N2 ......Page 983
2.2.4.3. Excitation of 02 ......Page 995
2.2.4.4. Excitation of CO ......Page 996
2.2.5. Excitation of hydrogen (other than H(2s) or H(2p)) and helium beams ......Page 997
2.3.1. Excitation in collisions between rare-gas ion beams and rare-gas atoms ......Page 1008
2.3.2. Excitation of N2 ......Page 1010
2.4. Differential cross-sections for inelastic collisions ......Page 1014
2.4.1. Collisions with He ......Page 1015
2.4.2. Collisions with Ne ......Page 1018
2.4.4. Collisions of Li+ with N2 and O2 ......Page 1020
3. Comparison of theory and experiment for collisions including excitation—a summary account ......Page 1024
3.1. One-electron cases—excitation in H+-H collisions ......Page 1025
3.1.1. Correlation with evidence from charge-changing and ionizing collisions ......Page 1027
3.2.2. Charge transfer to excited states of H ......Page 1028
3.4.1. Excitation of H ......Page 1029
3.4.3. Comparison with data on total cross-sections for ionization ......Page 1030
3.6.1. Comparison with data on ionization and charge transfer ......Page 1031
3.7. Concluding remarks ......Page 1032
Supplementary sheet with Figs. 20.22 and 20.30 ......Page 1033
AUTHOR INDEX ......Page 1035
SUBJECT INDEX ......Page 1049