Abstract

We have used a multi-particle imaging technique (COLTRIMS) to observe the double ionization of rare gas atoms by multi-photon absorption of 800 nm (1.5 eV) femto-second laser pulses and by single photon absorption (synchrotron radiation). Both processes are mediated by electron correlation. We discuss similarities and differences in the three-body final state momentum distributions.

© 2001 Optical Society of America

Full Article  |  PDF Article

References

  • View by:
  • |
  • |
  • |

  1. J. Briggs and V. Schmidt, “Differential cross sections for photo-double-ionization of the helium atom,” J. Phys. 33, R1 (2000).
  2. R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
    [Crossref]
  3. H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).
  4. H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).
  5. R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
    [Crossref] [PubMed]
  6. R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).
  7. R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
    [Crossref] [PubMed]
  8. A. Becker and F.H.M. Faisal, “Interpretation of Momentum Distribution of Recoil Ions from Laser Induced Nonsequential Double Ionization,” Phys. Rev. Lett. 84, 3546 (2000).
    [Crossref] [PubMed]
  9. Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
    [Crossref] [PubMed]
  10. R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
    [Crossref] [PubMed]
  11. R. Moshammer, B. Feuerstein, and J. Ullrich, “Nonsequential multiple ionization in intense laser pulses: interpretation of ion momentum distributions within the classical ‘rescattering’ model,” J. Phys B33, L823 (1992).
  12. K. Sacha and B. Eckhardt, “Pathways to double ionization of atoms in strong fields,” Phys. Rev. A:accepted for publication 2001, (2001).
  13. L.B. Fu J. Chen, J. Liu, and W. M. Zheng, “Interpretation of momentum distribution of recoil ions from laser-induced nonsequential double ionization by semiclassical rescattering model,” Phys. Rev. A63, 011404R (2000).
  14. M. Lein, E.K.U. Gross, and V. Engel “Intense-Field Double Ionization of Helium: Identifying the Mechanism,” Phys. Rev. Lett. 85, 4707 (2000).
    [Crossref] [PubMed]
  15. R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
    [Crossref] [PubMed]
  16. Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).
  17. K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)
  18. M. Lein, E.K.U. Gross, and V. Engel, “On the mechnism of strong-field double photoionisation in the helium atom,” J. Phys B 33, 433–442 (2000)
    [Crossref]
  19. F. Maulbetsch and J.S. Briggs, “Selection rules for transitions to two-electron continuum states,” J. Phys. B28, 551 (1995).
  20. I.E. McCarthy and E. Weigold, “Electron momentum spectroscopy of atoms and molecules,” Rep. Prog. Phys. 54, 789 (1991).
    [Crossref]
  21. A. Becker and F.H.M. Faisal, “Correlated Keldysh-Faisal-Reiss theory of above-threshold double ionization of He in intense laser fields,”, Phys. Rev. A50, 3256 (1994).
  22. J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).
  23. S. Keller, “Perturbation theory for (γ,2e) on helium,” J. Phys. B33, L513 (2000).
  24. Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).
  25. S. Bhattacharyya and S. Mitra, “Double photoionization of He by circularly polarized light: A QED approach,” Phys. Rev. 62, 032709 (2000).
    [Crossref]
  26. A. Becker and F. H. M. Faisal, “Mechanism of laser-induced double ionization of helium,” J. Phys. B29, L197 (1996).
  27. A. Becker and F.H.M. Faisal, “Interplay of electron correlation and intense field dynamics in the double ionization of helium,” Phys. Rev. A59, R1742 (1999).

2000 (12)

J. Briggs and V. Schmidt, “Differential cross sections for photo-double-ionization of the helium atom,” J. Phys. 33, R1 (2000).

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

A. Becker and F.H.M. Faisal, “Interpretation of Momentum Distribution of Recoil Ions from Laser Induced Nonsequential Double Ionization,” Phys. Rev. Lett. 84, 3546 (2000).
[Crossref] [PubMed]

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

L.B. Fu J. Chen, J. Liu, and W. M. Zheng, “Interpretation of momentum distribution of recoil ions from laser-induced nonsequential double ionization by semiclassical rescattering model,” Phys. Rev. A63, 011404R (2000).

M. Lein, E.K.U. Gross, and V. Engel “Intense-Field Double Ionization of Helium: Identifying the Mechanism,” Phys. Rev. Lett. 85, 4707 (2000).
[Crossref] [PubMed]

R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

M. Lein, E.K.U. Gross, and V. Engel, “On the mechnism of strong-field double photoionisation in the helium atom,” J. Phys B 33, 433–442 (2000)
[Crossref]

S. Keller, “Perturbation theory for (γ,2e) on helium,” J. Phys. B33, L513 (2000).

S. Bhattacharyya and S. Mitra, “Double photoionization of He by circularly polarized light: A QED approach,” Phys. Rev. 62, 032709 (2000).
[Crossref]

1999 (2)

A. Becker and F.H.M. Faisal, “Interplay of electron correlation and intense field dynamics in the double ionization of helium,” Phys. Rev. A59, R1742 (1999).

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

1998 (2)

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

1997 (1)

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

1996 (2)

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

A. Becker and F. H. M. Faisal, “Mechanism of laser-induced double ionization of helium,” J. Phys. B29, L197 (1996).

1995 (2)

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

F. Maulbetsch and J.S. Briggs, “Selection rules for transitions to two-electron continuum states,” J. Phys. B28, 551 (1995).

1994 (1)

A. Becker and F.H.M. Faisal, “Correlated Keldysh-Faisal-Reiss theory of above-threshold double ionization of He in intense laser fields,”, Phys. Rev. A50, 3256 (1994).

1993 (1)

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

1992 (1)

R. Moshammer, B. Feuerstein, and J. Ullrich, “Nonsequential multiple ionization in intense laser pulses: interpretation of ion momentum distributions within the classical ‘rescattering’ model,” J. Phys B33, L823 (1992).

1991 (2)

I.E. McCarthy and E. Weigold, “Electron momentum spectroscopy of atoms and molecules,” Rep. Prog. Phys. 54, 789 (1991).
[Crossref]

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Bartlett, R.J.

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Becker, A.

A. Becker and F.H.M. Faisal, “Interpretation of Momentum Distribution of Recoil Ions from Laser Induced Nonsequential Double Ionization,” Phys. Rev. Lett. 84, 3546 (2000).
[Crossref] [PubMed]

A. Becker and F.H.M. Faisal, “Interplay of electron correlation and intense field dynamics in the double ionization of helium,” Phys. Rev. A59, R1742 (1999).

A. Becker and F. H. M. Faisal, “Mechanism of laser-induced double ionization of helium,” J. Phys. B29, L197 (1996).

A. Becker and F.H.M. Faisal, “Correlated Keldysh-Faisal-Reiss theory of above-threshold double ionization of He in intense laser fields,”, Phys. Rev. A50, 3256 (1994).

Becker, U.

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Becker, W.

R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
[Crossref] [PubMed]

Berrah, N.

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Bhattacharyya, S.

S. Bhattacharyya and S. Mitra, “Double photoionization of He by circularly polarized light: A QED approach,” Phys. Rev. 62, 032709 (2000).
[Crossref]

Bräuning, H.

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Bräuning, H.P

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

Bräuning-Demian, A.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

Bray, I.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

Briggs, J.

J. Briggs and V. Schmidt, “Differential cross sections for photo-double-ionization of the helium atom,” J. Phys. 33, R1 (2000).

Briggs, J.S.

F. Maulbetsch and J.S. Briggs, “Selection rules for transitions to two-electron continuum states,” J. Phys. B28, 551 (1995).

Carnes, K.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

Chen, L.B. Fu J.

L.B. Fu J. Chen, J. Liu, and W. M. Zheng, “Interpretation of momentum distribution of recoil ions from laser-induced nonsequential double ionization by semiclassical rescattering model,” Phys. Rev. A63, 011404R (2000).

Cocke, C.L.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Dorn, A.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Dörner, R.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Dreuil, S.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

Dundas, D.

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

Eckhardt, B.

K. Sacha and B. Eckhardt, “Pathways to double ionization of atoms in strong fields,” Phys. Rev. A:accepted for publication 2001, (2001).

Engel, V.

M. Lein, E.K.U. Gross, and V. Engel “Intense-Field Double Ionization of Helium: Identifying the Mechanism,” Phys. Rev. Lett. 85, 4707 (2000).
[Crossref] [PubMed]

M. Lein, E.K.U. Gross, and V. Engel, “On the mechnism of strong-field double photoionisation in the helium atom,” J. Phys B 33, 433–442 (2000)
[Crossref]

Faisal, F. H. M.

A. Becker and F. H. M. Faisal, “Mechanism of laser-induced double ionization of helium,” J. Phys. B29, L197 (1996).

Faisal, F.H.M.

A. Becker and F.H.M. Faisal, “Interpretation of Momentum Distribution of Recoil Ions from Laser Induced Nonsequential Double Ionization,” Phys. Rev. Lett. 84, 3546 (2000).
[Crossref] [PubMed]

A. Becker and F.H.M. Faisal, “Interplay of electron correlation and intense field dynamics in the double ionization of helium,” Phys. Rev. A59, R1742 (1999).

A. Becker and F.H.M. Faisal, “Correlated Keldysh-Faisal-Reiss theory of above-threshold double ionization of He in intense laser fields,”, Phys. Rev. A50, 3256 (1994).

Feagin, J.

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Feagin, J.M.

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

Feuerstein, B.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

R. Moshammer, B. Feuerstein, and J. Ullrich, “Nonsequential multiple ionization in intense laser pulses: interpretation of ion momentum distributions within the classical ‘rescattering’ model,” J. Phys B33, L823 (1992).

Giessen, H.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Gross, E.K.U.

M. Lein, E.K.U. Gross, and V. Engel “Intense-Field Double Ionization of Helium: Identifying the Mechanism,” Phys. Rev. Lett. 85, 4707 (2000).
[Crossref] [PubMed]

M. Lein, E.K.U. Gross, and V. Engel, “On the mechnism of strong-field double photoionisation in the helium atom,” J. Phys B 33, 433–442 (2000)
[Crossref]

Heiser, F.

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Hemmers, O.

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Hino, Ken-ichi

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

Hoffmann, K.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Ishihara, T.

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

Jagutzki, O.

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Jung, M.

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Kanter, E.P.

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Keller, S.

S. Keller, “Perturbation theory for (γ,2e) on helium,” J. Phys. B33, L513 (2000).

Kheifets, A.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

Khemliche, H.

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Kopold, R.

R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
[Crossref] [PubMed]

Korn, G.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Krässig, B.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

Kravis, S.

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Langer, B.

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Lein, M.

M. Lein, E.K.U. Gross, and V. Engel “Intense-Field Double Ionization of Helium: Identifying the Mechanism,” Phys. Rev. Lett. 85, 4707 (2000).
[Crossref] [PubMed]

M. Lein, E.K.U. Gross, and V. Engel, “On the mechnism of strong-field double photoionisation in the helium atom,” J. Phys B 33, 433–442 (2000)
[Crossref]

Liu, J.

L.B. Fu J. Chen, J. Liu, and W. M. Zheng, “Interpretation of momentum distribution of recoil ions from laser-induced nonsequential double ionization by semiclassical rescattering model,” Phys. Rev. A63, 011404R (2000).

Maulbetsch, F.

F. Maulbetsch and J.S. Briggs, “Selection rules for transitions to two-electron continuum states,” J. Phys. B28, 551 (1995).

McCarthy, I.E.

I.E. McCarthy and E. Weigold, “Electron momentum spectroscopy of atoms and molecules,” Rep. Prog. Phys. 54, 789 (1991).
[Crossref]

McGuire, J.H.

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

Menzel, A.

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Mergel, V.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Mitra, S.

S. Bhattacharyya and S. Mitra, “Double photoionization of He by circularly polarized light: A QED approach,” Phys. Rev. 62, 032709 (2000).
[Crossref]

Moshammer, R.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

R. Moshammer, B. Feuerstein, and J. Ullrich, “Nonsequential multiple ionization in intense laser pulses: interpretation of ion momentum distributions within the classical ‘rescattering’ model,” J. Phys B33, L823 (1992).

Parker, J.S.

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

Prior, M.H.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Richard, P.

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

Rottke, H.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
[Crossref] [PubMed]

Sacha, K.

K. Sacha and B. Eckhardt, “Pathways to double ionization of atoms in strong fields,” Phys. Rev. A:accepted for publication 2001, (2001).

Samson, J.A.R.

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Sandner, W.

R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
[Crossref] [PubMed]

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Schlachter, A.S.

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Schmidt, V.

J. Briggs and V. Schmidt, “Differential cross sections for photo-double-ionization of the helium atom,” J. Phys. 33, R1 (2000).

Schmidt-Böcking, H.

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Schmitt, W.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Schöter, C.T.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Shimizu, F.

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

Smyth, E.

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

Spielberger, L.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Staudte, A.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Tanis, J.A.

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

Taylor, K.T.

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

Toshima, N.

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

Trump, C.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Ullrich, J.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

R. Moshammer, B. Feuerstein, and J. Ullrich, “Nonsequential multiple ionization in intense laser pulses: interpretation of ion momentum distributions within the classical ‘rescattering’ model,” J. Phys B33, L823 (1992).

Unverzagt, M.

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Urbasch, G.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Vitirito, S.

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

Vogt, T.

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

Vollmer, M.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Weber, Th.

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Weckenbrock, M.

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Wehlitz, R.

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

Weigold, E.

I.E. McCarthy and E. Weigold, “Electron momentum spectroscopy of atoms and molecules,” Rep. Prog. Phys. 54, 789 (1991).
[Crossref]

Wittmann, M.

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

Zheng, W. M.

L.B. Fu J. Chen, J. Liu, and W. M. Zheng, “Interpretation of momentum distribution of recoil ions from laser-induced nonsequential double ionization by semiclassical rescattering model,” Phys. Rev. A63, 011404R (2000).

J. Phys (1)

R. Moshammer, B. Feuerstein, and J. Ullrich, “Nonsequential multiple ionization in intense laser pulses: interpretation of ion momentum distributions within the classical ‘rescattering’ model,” J. Phys B33, L823 (1992).

J. Phys B (1)

M. Lein, E.K.U. Gross, and V. Engel, “On the mechnism of strong-field double photoionisation in the helium atom,” J. Phys B 33, 433–442 (2000)
[Crossref]

J. Phys. (7)

F. Maulbetsch and J.S. Briggs, “Selection rules for transitions to two-electron continuum states,” J. Phys. B28, 551 (1995).

J. Briggs and V. Schmidt, “Differential cross sections for photo-double-ionization of the helium atom,” J. Phys. 33, R1 (2000).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Recoil ion and electronic angular asymmetry parameters for photo double ionization of helium at 99 eV,” J. Phys. B30, L649 (1997).

H.P Bräuning, R. Dörner, C.L. Cocke, M.H. Prior, B. Krässig, A. Kheifets, I. Bray, A. Bräuning-Demian, K. Carnes, S. Dreuil, V. Mergel, P. Richard, J. Ullrich, and H. Schmidt-Böcking, “Absolute triple differential cross sections for photo-double ionization of helium - experiment and theory,” J. Phys. B31, 5149 (1998).

J.H. McGuire, N. Berrah, R.J. Bartlett, J.A.R. Samson, J.A. Tanis, C.L. Cocke, and A.S. Schlachter, “The ratio of cross sections for double to single ionization of helium by high energy photons and charged particles,” J. Phys. B28, 913 (1995).

S. Keller, “Perturbation theory for (γ,2e) on helium,” J. Phys. B33, L513 (2000).

A. Becker and F. H. M. Faisal, “Mechanism of laser-induced double ionization of helium,” J. Phys. B29, L197 (1996).

Laser Physics (1)

K.T. Taylor, J.S. Parker, D. Dundas, E. Smyth, and S. Vitirito, “Laser Driven Helium in Full- Dimensionality,” Laser Physics 9, 98–116 (1999)

Nature (1)

Th. Weber, H. Giessen, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, and R. Dörner, “Correlated electron emission in multiphoton double ionization,” Nature 404, 608 (2000).

Phys. Rev. (6)

L.B. Fu J. Chen, J. Liu, and W. M. Zheng, “Interpretation of momentum distribution of recoil ions from laser-induced nonsequential double ionization by semiclassical rescattering model,” Phys. Rev. A63, 011404R (2000).

R. Dörner, H. Bräuning, J.M. Feagin, V. Mergel, O. Jagutzki, L. Spielberger, T. Vogt, H. Khemliche, M.H. Prior, J. Ullrich, C.L. Cocke, and H. Schmidt-Böcking, “Photo-double-ionization of He: Fully differential and absolute electronic and ionic momentum distributions,” Phys. Rev. A57, 1074 (1998).

A. Becker and F.H.M. Faisal, “Interplay of electron correlation and intense field dynamics in the double ionization of helium,” Phys. Rev. A59, R1742 (1999).

A. Becker and F.H.M. Faisal, “Correlated Keldysh-Faisal-Reiss theory of above-threshold double ionization of He in intense laser fields,”, Phys. Rev. A50, 3256 (1994).

Ken-ichi Hino, T. Ishihara, F. Shimizu, N. Toshima, and J.H. McGuire, “Double photoionization of helium using many-body perturbation theory,” Phys. Rev. A48, 1271 (1993).

S. Bhattacharyya and S. Mitra, “Double photoionization of He by circularly polarized light: A QED approach,” Phys. Rev. 62, 032709 (2000).
[Crossref]

Phys. Rev. Lett. (7)

R. Wehlitz, F. Heiser, O. Hemmers, B. Langer, A. Menzel, and U. Becker, “Electron-energy and -angular distributions in the double photoionization of helium,” Phys. Rev. Lett. 67, 3764 (1991).
[Crossref] [PubMed]

A. Becker and F.H.M. Faisal, “Interpretation of Momentum Distribution of Recoil Ions from Laser Induced Nonsequential Double Ionization,” Phys. Rev. Lett. 84, 3546 (2000).
[Crossref] [PubMed]

Th. Weber, M. Weckenbrock, A. Staudte, L. Spielberger, O. Jagutzki, V. Mergel, G. Urbasch, M. Vollmer, H. Giessen, and R. Dörner, “Recoil-Ion Momentum Distributions for Single and Double Ionization of Helium in Strong Laser Fields,” Phys. Rev. Lett. 84, 443 (2000).
[Crossref] [PubMed]

R. Moshammer, B. Feuerstein, W. Schmitt, A. Dorn, C.T. Schöter, J. Ullrich, H. Rottke, C. Trump, M. Wittmann, G. Korn, K. Hoffmann, and W. Sandner, “Momentum Distributions of Nn+ Ions Created by an Intense Ultrashort Laser Pulse,” Phys. Rev. Lett. 84, 447 (2000).
[Crossref] [PubMed]

R. Dörner, J. Feagin, C.L. Cocke, H. Bräuning, O. Jagutzki, M. Jung, E.P. Kanter, H. Khemliche, S. Kravis, V. Mergel, M.H. Prior, H. Schmidt-Böcking, L. Spielberger, J. Ullrich, M. Unverzagt, and T. Vogt, “Fully Differential Cross Sections for Double Photoionization of He Measured by Recoil Ion Momentum Spectroscopy,” Phys. Rev. Lett. 77, 1024 (1996).
[Crossref] [PubMed]

M. Lein, E.K.U. Gross, and V. Engel “Intense-Field Double Ionization of Helium: Identifying the Mechanism,” Phys. Rev. Lett. 85, 4707 (2000).
[Crossref] [PubMed]

R. Kopold, W. Becker, H. Rottke, and W. Sandner, “Routes to Nonsequential Double Ionization,” Phys. Rev. Lett. 85, 3781 (2000).
[Crossref] [PubMed]

Physics Reports (1)

R. Dörner, V. Mergel, O. Jagutzki, L. Spielberger, J. Ullrich, R. Moshammer, and H. Schmidt-Böcking, “Cold Target Recoil Ion Momentum Spectroscopy: A ‘momentum microscope’ to view atomic collision dynamics,” Physics Reports 330, 96–192 (2000).
[Crossref]

Rep. Prog. Phys. (1)

I.E. McCarthy and E. Weigold, “Electron momentum spectroscopy of atoms and molecules,” Rep. Prog. Phys. 54, 789 (1991).
[Crossref]

Other (1)

K. Sacha and B. Eckhardt, “Pathways to double ionization of atoms in strong fields,” Phys. Rev. A:accepted for publication 2001, (2001).

Supplementary Material (3)

» Media 1: MOV (1422 KB)     
» Media 2: MOV (734 KB)     
» Media 3: MOV (1654 KB)     

Cited By

OSA participates in Crossref's Cited-By Linking service. Citing articles from OSA journals and other participating publishers are listed here.

Alert me when this article is cited.


Figures (5)

Fig. 1.
Fig. 1.

Experimental setup. Electrons (red) and ions (blue) are created in the supersonic gas jet target. The thin copper rings create a homogeneous electric field, the large Helmoltz coils an additional magnetic field. These fields guide the charged particles onto fast time and position sensitive channel plate detectors (Roentdek www.roentdek.com). Time-of-flight and position of impact of each electron-ion pair is recorded in list mode. From this the three dimensional momentum vector of each particle can be calculated. [Media 1]

Fig. 2.
Fig. 2.

Momentum distribution of He 1+ ions. Left: For 85 eV single photon absorption. Right: 1.5 eV (800nm), 220 fsec, 1.4×1015 W/cm2. The polarization vector of the light is horizontal. The photon momentum is vertical. In the left figure the momentum component in the third dimension out of the plane of the figure is restricted to ±0.4a.u., the right panel is integrated over the momenta in the direction out of the plane of the figure

Fig. 3.
Fig. 3.

Momentum distribution of He 2+ ions. Left: For 99 eV single photon absorption. Right: 1.5 eV (800nm), 220 fsec, 6.6×1014 W/cm2. The polarization vector is horizontal. The two bottom panels show projections of the distributions on the polarization axis.

Fig. 4.
Fig. 4.

Momentum correlation between the two emitted electrons. Left and middle: Helium, doubly ionized by absorption of one 99eV photon. Left: The horizontal axis shows the momentum components of one electron along the polarization axis, the vertical axis the same momentum component of the corresponding second electron. Middle: Like left, but the momentum components along an axis perpendicular to the polarization is shown. The Quicktime movie (0.7MB) shows the transition between the left and middle distribution. I.e. the axis along which the momentum components are taken is rotating as indicated by the red double arrow. Right: Corresponding figure to the left one but for multi-photon double ionization of Argon by in the focus of a 220 fsec, 800nm laser pulse at peak intensities of 3.8.1014 W/cm2. In all three figures the same sign of the momenta for both electrons means emission to the same half sphere, however the plane which divides the two half spheres is rotated in the middle panel. The data are integrated over the momentum components in the direction perpendicular to the polarization. The color coding shows the differential rate on linear scale in arbitrary units.

Fig. 5.
Fig. 5.

Double ionization of helium by single photon absorption at 99 eV. The electrons have equal energies. One electron is emitted along the red arrow, the angular distribution of the second electron is shown by the data points in a polar plot. The distance from the origin shows the cross section. The blue line shows the location of the node according to selection rule 2 (see text). The dotted red line shows the node according to selection rule 1 (see text). The polarization axis is horizontal. The Quicktime Movie (1.7MB)shows the change of the distribution as the direction of the first electron changes its angle with respect to the polarization axis

Metrics