H. Klar

3.2k total citations · 1 hit paper
84 papers, 2.6k citations indexed

About

H. Klar is a scholar working on Atomic and Molecular Physics, and Optics, Radiation and Spectroscopy. According to data from OpenAlex, H. Klar has authored 84 papers receiving a total of 2.6k indexed citations (citations by other indexed papers that have themselves been cited), including 78 papers in Atomic and Molecular Physics, and Optics, 18 papers in Radiation and 18 papers in Spectroscopy. Recurrent topics in H. Klar's work include Atomic and Molecular Physics (67 papers), Advanced Chemical Physics Studies (34 papers) and Mass Spectrometry Techniques and Applications (15 papers). H. Klar is often cited by papers focused on Atomic and Molecular Physics (67 papers), Advanced Chemical Physics Studies (34 papers) and Mass Spectrometry Techniques and Applications (15 papers). H. Klar collaborates with scholars based in Germany, United States and Italy. H. Klar's co-authors include J S Briggs, M Brauner, Jamal Berakdar, Maximilian Klar, Hans Kleinpoppen, A. Franz, K. Jung, H. Ehrhardt, P Schlemmer and U. Fano and has published in prestigious journals such as Physical Review Letters, Physics Reports and Chemical Physics Letters.

In The Last Decade

H. Klar

83 papers receiving 2.4k citations

Hit Papers

Triply-differential cross sections for ionisation of hydr... 1989 2026 2001 2013 1989 200 400 600
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. Triply-differential cross sections for ionisation of hydrogen atoms by electrons and positrons
    1989 604 citations J S Briggs, H. Klar et al. Journal of Physics B Atomic Molecular and Optical Physics profile →

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
H. Klar Germany 27 2.5k 723 555 514 342 84 2.6k
C. J. Joachain Belgium 37 3.8k 1.5× 572 0.8× 714 1.3× 945 1.8× 717 2.1× 121 3.9k
Robin Shakeshaft United States 36 3.8k 1.5× 823 1.1× 456 0.8× 408 0.8× 615 1.8× 147 3.9k
K L Bell United Kingdom 28 2.3k 0.9× 570 0.8× 604 1.1× 673 1.3× 237 0.7× 177 3.1k
F. W. Byron United States 32 2.7k 1.1× 501 0.7× 890 1.6× 633 1.2× 333 1.0× 57 2.8k
Hans Kleinpoppen United Kingdom 31 2.9k 1.1× 512 0.7× 1.2k 2.1× 464 0.9× 177 0.5× 135 3.4k
D. W. Norcross United States 31 2.6k 1.0× 574 0.8× 495 0.9× 426 0.8× 202 0.6× 68 2.8k
J. M. Wadehra United States 21 1.5k 0.6× 369 0.5× 271 0.5× 487 0.9× 250 0.7× 72 1.9k
Kwong T. Chung United States 34 2.9k 1.2× 573 0.8× 338 0.6× 282 0.5× 512 1.5× 131 3.0k
R.K. Janev North Macedonia 25 1.9k 0.7× 615 0.9× 257 0.5× 461 0.9× 586 1.7× 127 2.6k
A. Russek United States 21 1.7k 0.7× 509 0.7× 453 0.8× 202 0.4× 166 0.5× 56 1.9k

Countries citing papers authored by H. Klar

Since Specialization
Citations

This map shows the geographic impact of H. Klar's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by H. Klar with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites H. Klar more than expected).

Fields of papers citing papers by H. Klar

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by H. Klar. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by H. Klar. The network helps show where H. Klar may publish in the future.

Co-authorship network of co-authors of H. Klar

This figure shows the co-authorship network connecting the top 25 collaborators of H. Klar. A scholar is included among the top collaborators of H. Klar based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with H. Klar. H. Klar is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Klar, H.. (2021). The Banach Space of Multiply Excited Atoms. Journal of Applied Mathematics and Physics. 9(12). 3230–3239.
2.
Klar, H.. (2020). Dominant Correlation Effects in Two-Electron Atoms. Journal of Applied Mathematics and Physics. 8(7). 1424–1433. 2 indexed citations
3.
Klar, H., et al.. (1999). from laser-excited atoms with spin-polarized electrons. Journal of Physics B Atomic Molecular and Optical Physics. 32(7). 1647–1656. 3 indexed citations
4.
Dorn, Alexander, et al.. (1998). Orientational Dichroism in the Electron-Impact Ionization of Laser-Oriented Atomic Sodium. Physical Review Letters. 80(2). 257–260. 23 indexed citations
5.
Klar, H., et al.. (1997). Two-electron atoms in double continua: asymptotic wavefunctions. Journal of Physics B Atomic Molecular and Optical Physics. 30(22). L811–L814. 6 indexed citations
6.
Berakdar, Jamal, J S Briggs, & H. Klar. (1993). Scaling behaviour of the triply differential cross section for the ionization of atomic hydrogen. Journal of Physics B Atomic Molecular and Optical Physics. 26(2). 285–296. 36 indexed citations
7.
Klar, H., Dmitry A. Konovalov, & I. E. McCarthy. (1993). Calculation of ionization with an error estimate. Journal of Physics B Atomic Molecular and Optical Physics. 26(20). L711–L716. 6 indexed citations
8.
Berakdar, Jamal, H. Klar, A. Huetz, & P. Selles. (1993). Chiral electron pairs from double photoionization. Journal of Physics B Atomic Molecular and Optical Physics. 26(8). 1463–1478. 61 indexed citations
9.
Klar, H.. (1989). Periodic orbits in atomic hydrogen exposed to circularly polarised laser light. Zeitschrift für Physik D Atoms Molecules and Clusters. 11(1). 45–52. 16 indexed citations
10.
Avaldi, L., R. Camilloni, E. Fainelli, et al.. (1987). Absolute triple differential cross sections for electron impact ionisation of He at 1024.6 eV incident energy. Journal of Physics B Atomic and Molecular Physics. 20(21). 5827–5838. 29 indexed citations
11.
Klar, H.. (1986). Equilibrium atomic structure: Rotating atoms. Physical Review Letters. 57(1). 66–69. 19 indexed citations
12.
Klar, H. & A. Franz. (1986). Post-collision-interaction effects in the ionization of helium by fast electrons at small momentum transfer. Physical review. A, General physics. 33(3). 2103–2105. 23 indexed citations
13.
Klar, H.. (1986). Equilibrium atomic structure: Rotating atoms. Zeitschrift für Physik D Atoms Molecules and Clusters. 3(4). 353–358. 5 indexed citations
14.
Jung, K., et al.. (1985). Absolute triple differential cross sections of electron impact ionisation of helium at 600 eV collision energy. Journal of Physics B Atomic and Molecular Physics. 18(14). 2955–2966. 55 indexed citations
15.
Klar, H.. (1985). Generalised power series solutions for non-separable wave equations. Journal of Physics B Atomic and Molecular Physics. 18(15). L475–L479. 1 indexed citations
16.
Klar, H.. (1985). Exact atomic wavefunctions: a generalised power series expansion using hyperspherical coordinates. Journal of Physics A Mathematical and General. 18(9). 1561–1570. 17 indexed citations
17.
Klar, H., et al.. (1983). Treatment of the positron-hydrogen system in hyperspherical coordinates. The European Physical Journal A. 310(3). 153–158. 29 indexed citations
18.
Klar, H.. (1981). Screening effects on Wannier's theory of atomic threshold ionisation. Journal of Physics B Atomic and Molecular Physics. 14(17). 3255–3265. 46 indexed citations
19.
Klar, H.. (1980). Polarisation of fluorescence radiation following atomic photoionisation. Journal of Physics B Atomic and Molecular Physics. 13(10). 2037–2049. 32 indexed citations
20.
Klar, H.. (1977). Adiabatic analysis of atomic collisions. II. Properties of velocity-coupled channels. Physical review. A, General physics. 15(4). 1452–1458. 36 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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