Homepage of Walter Johnson (Notre Dame University)
Walter R. Johnson
Frank M. Freimann Professor of Physics (Emeritus) Department of Physics
225 Nieuwland Science University of Notre Dame
Notre Dame, IN 46556
Tel. (574) 631-6651
Fax. (574) 631-5952
Cell. (574) 274-7048
Relativistic and correlation effects in heavy atoms, including relativistic
Hartree Fock calculations, relativistic many-body perturbation theory (MBPT)
calculations, and iterative singles-doubles (SD) all-order methods.
Present efforts:
Nonlinear terms in SD coupled cluster equations.
Third-Order MBPT for systems with two valence electrons.
Extending
the SD method to systems with two or three valence electrons.
Applications of MBPT to give accurate energies, transition rates, and hyperfine
constants for low-lying levels of ions in various isoelectronic sequences.
These studies include the Li, Na, Cu, Ne, Be,
B, Mg, Pd, and Ag sequences.
Applications of all-order SD methods to alkali-metal atoms
from Li to Fr.
Weak interactions in heavy atoms atoms. Calculations of PNC amplitudes
and electric dipole enhancement factors.
CI calculations of energies, transition probabilities, hyperfine quenching,
polarizabilities, and two-photon transitions in heliumlike ions.
Applications of the relativistic random-phase approximation (RRPA) to photoionization,
including non-dipole corrections to angular distributions.
Average atom model of a plasma and the Ziman theory of conductivity in the average-atom
approximation. Kubo-Greenwood
theory in the average atom approximation applied to the frequency-dependent conductivity
and optical response of a warm dense plasma.
Compton Scattering of xrays in the average-atom approximation.
Participant in Conference "20 Years of Spectroscopy with the
Electron Beam Ion Trap", Berkeley, CA, Nov 12-16, 2006.
Two lectures at the conference
"Cross-talks in the physics of many-body systems"
entitled Many-Body Methods Applied to
Parity Nonconserving Transitions in Atoms: The Weak Charge and
Anapole Moment of ^{133}Cs
Organizer of Program entitled Atomic, Chemical, and Nuclear
Developments in Coupled Cluster Methods, Institute for Nuclear Theory,
University of Washington, Seattle, June 23-July 25, 2008.
Member of Panel on "Atomic Physics of High-Z Atoms" at the Department of Energy "Research Needs Workshop" (ReNeW)
for "High Energy Density Laboratory Plasmas" (HEDLP), Rockville, MD, Nov. 15-18 (2009).
Invited talk entitled Thomson Scattering in the Average-Atom Approximation
at Workshop VI: Computational Challenges in Warm Dense Matter, held at the Institute for Pure & Applied
Mathematics, UCLA, May 21-25 (2012).
Atomic Structure Theory:
Lectures on Atomic Physics,
Walter R. Johnson, Springer Verlag, Berlin (ISBN 978-3-540-68010-9).
A textbook on atomic structure for students with a background in
quantum mechanics. (Available from amazon.com )
Supplementary material for this book is available at
Atomic Structure Material
Thomson Scattering in the Average-Atom Approximation,
W.R. Johnson, J. Nilsen and K.T. Cheng,
Phys. Rev. E 86, 036410 (2012).
arXiv:1207.0178
Using the X-FEL to understand X-ray Thomson scattering for partially
ionized plasmas, J. Nilsen, W.R. Johnson and K.T. Cheng,
13th International Conference on X-ray Lasers Paris, France June 10,
2012 through June 15, 2012, Report-no: LLNL-PROC-564720.
arXiv:1207.5075
Average-Atom Model for X-ray Scattering from Warm Dense Matter,
W.R. Johnson, J. Nilsen and K.T. Cheng,
Submitted to proceedings of Workshop IV: Computational Challenges in Warm Dense Matter IPAM (UCLA) May 21 - 25 (2012).
arXiv:1211.0227
The effect of bound states on X-ray Thomson scattering for partially ionized plasmas,
J. Nilsen, W.R. Johnson and K.T. Cheng, High Energy Density Physics, 9, 388-391 (2013).
arXiv:1212.5972
Resonant Bound-Free Contributions to Thomson Scattering of X-rays by Warm Dense Matter,
W.R. Johnson, J. Nilsen and K.T. Cheng,
High Energy Density Physics, 9, 407-409 (2013).
arXiv:1301.3440
X-ray Thomson scattering for partially ionized plasmas including the effect of bound levels,
J. Nilsen, W.R. Johnson and K.T. Cheng,
X-Ray Lasers and Coherent X-Ray Sources: Developement and Applications X, Proceedings of SPIE 2013, p. 8849
arXiv:1309.6281
Thomson scattering from a three-component plasma,
W.R. Johnson and J. Nilsen,
Phys. Rev. E, 89, 023107 (2014).
PDF
Using the X-FEL to Understand X-Ray Thomson Scattering for Partially Ionized Plasmas,
J. Nilsen, W. R. Johnson and K. T. Cheng, X-Ray Lasers 2012, Springer Proceedings in Physics, 147, 193-198 (2014)
Average-atom treatment of relaxation time in X-ray Thomson scattering from warm-dense matter,
W. R. Johnson and J. Nilsen, Phys. Rev. E, 93, 033295 (2016). arXiv:1512.09155v4
Relativistic many-body calculation of energies, lifetimes, polarizabilities, blackbody
radiative shift, and hyperfine constants in Lu^{2+},
U. I. Safronova, M. S. Safronova and W. R. Johnson, Phys. Rev. A, 94 032506 (2016). arXiv:1607.003880v3
Forbidden M1 and E2 transitions in monovalent atoms and ions,
U. I. Safronova, M. S. Safronova and W. R. Johnson, Phys. Rev. A, 95, 042507 (2017). arXiv:1611.01191
X-ray line coincidence photopumping in a solar flare,
F. P. Keenan, K. Poppenhaeger, M. Mathioudakis, S. J. Rose, J. Flowerdew, D. Hynes,
Damian J. Christian, J. Nilsen and W. R. Johnson, Submitted to Nature Astronomy (2017). PDF
Other (Unpublished) Atomic Physics Material
Non-dipole angular distribution parameters for rare gas atoms (graphs),
W. R. Johnson (1999).
PDF
- 204K
Non-dipole angular distribution parameters for rare gas atoms (tables),
W. R. Johnson (1999).
TableI.txt
TableII.txt
Lennard-Jones potential inside a spherical cavity, W. R. Johnson
(2001).
PDF - 60K
Higher-Order Calculations of Atomic Polarizabilities, W. R. Johnson
and M. S. Safronova (2001).
PDF - 93K
Note on the Uehling Potential, W. R. Johnson (2001).
PDF
- 44K
Pressure in the Average-Atom Model, W. R. Johnson (2002).
PDF
- 78K
Free-Particle Continuum Density, W. R. Johnson (2002).
PDF
- 65K
Two-photon energy distributions for decay of 2^{1}S_{0}
states of He-like ions (Z=2-30), W. R. Johnson (2002).
ascii
- 25K
Note on the atomic edm and Schiff's theorem, W. R. Johnson (2002).
PDF
- 70K
Comments on the hyperfine structure of the 6p3/2 state of Cs,
W. R. Johnson (2003).
PDF
- 90K
Note on the anomalous moment corrections to transition amplitudes, W. R. Johnson (2002).
PDF
- 107K
A and B Hyperfine Constants and Isotope Shifts for Mg+, W. R. Johnson (2007).
PDF
Second-Order Hyperfine Effects in Mg and Ca, W. R. Johnson (2007).
PDF
Influence of second-order dipole-quadrupole corrections on the octupole
hyperfine constant C in ^{133}Cs, W. R. Johnson (2007).
PDF
Gauge Dependence of Two-Photon Matrix Elements,
W. R. Johnson (2007).
PDF
Scalar and Tensor Polarizabilities of Atoms,
W. R. Johnson (2009)
PDF
Relativistic Calculations of Transition Amplitudes
in the Helium Isoelectronic Sequencs (Advances in Atomic,
Molecular and Optical Physics 35, 225-329 (1995). [This is an article-class version -
the figures in the original article are modified here.]
W.R. Johnson, D.R. Plante, and J. Sapirstein (1995)
PDF
Folding a Gaussian into Theoretical Data,
W. R. Johnson (2012).
PDF
Atomic Theory Group at Notre Dame, Close Collaborators
& Visitors