(Non-Table Version)

NISTPhysics LaboratoryPhysical Reference Data


Physical Constants   Fundamental Physical Constants
   updated  Searchable Bibliography on the Constants
  International System of Units (SI)
    Guidelines for Evaluating and Expressing Measurement Uncertainty
Atomic Spectroscopic Data   Atomic Spectroscopic Database
   updated  Ground Levels and Ionization Energies for the Neutral Atoms
  Spectrum of Platinum Lamp for Ultraviolet Spectrograph Calibration
  Bibliographic Database on Atomic Transition Probabilities
  Status of Atomic Spectroscopic Data
Molecular Spectroscopic Data   Wavenumber Tables for Calibration of Infrared Spectrometers
  Frequencies for Interstellar Molecular Microwave Transitions
Ionization Data  updated  Electron-Impact Ionization Cross Section Database
X-Ray and Gamma-Ray Data   Note on x-ray attenuation databases
  X-ray Attenuation and Absorption for Materials of Dosimetric Interest
   updated  XCOM: Photon Cross Sections Database
   updated  Bibliography of Photon Attenuation Measurements
  X-Ray Form Factor, Attenuation and Scattering Tabulation
Radiation Dosimetry Data  new  Stopping-Power and Range Tables for Electrons, Protons, and Helium Ions
Nuclear Physics Data   Radionuclide Half-life Measurements Made at NIST
Condensed Matter Physics Data   Atomic Model Data for Electronic Structure Calculations
Other NIST Data   Online Reference Databases
  Standard Reference Data Catalog

The use of International Units and the expression of uncertainty in measurement is critical to all data activities. For information on these topics, see guidelines for evaluating and expressing measurement uncertainty, and information on the International System of Units (SI).

Additional data and databases are being prepared for this server.

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Inquiries or comments: www@physics.nist.gov.
Last update: October 1998