CCC Data Base

Welcome to the CCC Data Base for atomic targets!

For molecular targets go to https://mccc-db.org.

Created by Yuri Ralchenko and Igor Bray. Extended by Karen Lewis to include magnetic sublevel data for helium and by Nicolas Mori to include positron, proton, and relativistic data.

Disclaimer: Chances are that what you want is not here. However, your chances of success increase if you let me know what is missing! Please note that

The CCC method yields accurate excitation and ionisation cross sections for atomic and ionic targets which are well-modelled by one or two valence electrons above a Hartree-Fock core.
Inner core ionisation can be a major contributor to the total ionisation cross section. Such contributions can be estimated using various forms of Born-based approximations. Contact me at I.Bray@curtin.edu.au for details.

Current electron data:

Hydrogen I (https://link.aps.org/doi/10.1103/PhysRevA.46.6995) (complete n_i ≤ 9 data set as at March/2026, including averaged over n_i and summed over n_f, e-H_XSEC_LS.zip)
Helium I (https://link.aps.org/doi/10.1103/PhysRevA.52.1279)
Helium II (https://doi.org/10.1088/0953-4075/26/23/006)
Lithium I (https://link.aps.org/doi/10.1103/PhysRevA.49.1066)
Beryllium I (https://doi.org/10.1088/0953-4075/30/24/023)
Sodium I (https://link.aps.org/doi/10.1103/PhysRevA.49.1066)
Tin I (https://doi.org/10.1016/j.adt.2023.101586)

Current positron data:

Beryllium I (Submitted)
Boron I (https://doi.org/10.3390/atoms12070036)
Carbon I (https://doi.org/10.1103/PhysRevA.107.032817)
Oxygen I (https://doi.org/10.1140/epjd/s10053-023-00762-x)
Fluorine I (https://doi.org/10.1088/1361-6455/ad7f35)
Neon I (https://doi.org/10.1140/epjd/s10053-024-00809-7)
Argon I (https://doi.org/10.1140/epjd/s10053-024-00809-7)
H-like ions (Li III, Be IV, B V, C VI, N VII, O VIII, F IX) (https://doi.org/10.1088/1361-6455/adba9e)

Current proton data:

Helium I (https://doi.org/10.1103/y3hw-kyc4)