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Stopping-Power & Range Tables for Electrons, Protons, and Helium Ions

NIST Standard Reference Database 124

Last Update to Data Content: July 2017 | NISTIR 4999 | Version History | Disclaimer | DOI:

M.J. Berger1, J.S. Coursey2, M.A. Zucker2 and J. Chang2
1National Institute of Standards and Technology (NIST), Physics Laboratory (now Physical Measurement Laboratory (PML)), Ionizing Radiation Division (deceased)
2NIST, Physics Laboratory (now PML), Office of Electronic Commerce in Scientific and Engineering Data

Updated by: S.M. Seltzer and P.M. Bergstrom - both of PML Radiation Physics Division


The databases ESTAR, PSTAR, and ASTAR calculate stopping-power and range tables for electrons, protons, or helium ions, according to methods described in ICRU Reports 37 and 49. Stopping-power and range tables can be calculated for electrons in any user-specified material and for protons and helium ions in 74 materials.


The data for graphite, air and water have been recently re-evaluated by a committee of the ICRU resulting in ICRU Report 90.

The main findings of this report are provided in this summary (PDF).


  1. Introduction
  2. ESTAR: Stopping Powers and Ranges for Electrons
  3. PSTAR and ASTAR: for Protons and Helium Ions (alpha particles)
  4. References
  5. Appendix: Significance of Calculated Quantities

Access the Data:

  1. Electrons 
  2. Protons 
  3. Helium Ions

This work was supported in part by the Department of Energy, Office of Health and Environmental Research, Washington, D.C. 20585; and by NIST's Systems Integration for Manufacturing Applications (SIMA) Program.

NIST Standard Reference Database 124 | Customer Support | Online: October 1998 | Last update: July 2017


Created October 7, 2009, Updated November 15, 2019