In principle, most of the inputs and outputs should be self-explanatory.


Please enable Javascript and cookies in your web browser, they are strictly required by beamcalc. Concerning Javascript, I test the codes only on Firefox and (mobile) Safari browsers. I don't have the resources to debug the code on anything else, in particular for variations between each Javascript implementation. Cookies are used by beamcalc to pass on user input from one tab to the other.
Please note, that some browsers in some configurations use either commas or dots as decimal separators. Try using the respective other, if your calculations fail unexpectedly.

Ion tab

Ion mass in atomic mass units (amu). The loupe button (🔎) directs you to a ion picker dialogue using either from tabulated values (AMDC AME 2016) or using Weizsäckers mass formula for unknown and exotic Z/N combinations.
Ecool energy
The equivalent energy of electrons at cooling condition, i.e. <vi> = <ve>. Clicking on the link solves the electron-tab including spacecharge corrections for electron cooling at the present ion energy.
Revolution frequency of ions circulating in the ring on nominal orbit.
Momentum-compaction factor.
Dispersion of the revolution frequency.
max. particles
Maximum number of particles at the space charge limit for coasting and cooled beam.
Tuneshift due to space charge, per μA and assuming cooled beam with emittance of 1 π·mm·mrad.

Electron tab

keep fixed / set free
Keep the energy of the electrons fixed and vary the acceleration potential or set the electron energy free and keep the acceleration potential fixed.
Ion energy
The ion energy at cooling condition, i.e. <vi> = <ve>.
Clicking on the link matches the ion-tab to the present electron energy.

Lifetime tab

Please set up the ion- and electron-tabs for your specific ion beam or the calculations in the lifetime-tab may be meaningless.

Several simplifications are applied to the code to keep the calculations tractable and responsive. They are meant as rule-of-thumb guide, not as definitive answer to all pressing problems of humanity. If you need exact results, please consult your friendly theoretician. Most of all, for now all calculations are performed assuming beams of atomic ions, i.e. any kind of nuclear or molecular physics are ignored from estimations of cross sections and lifetimes.

e-1-Lifetime of ion beam through charge exchange (Schlachter et al., 1983).
... through stripping on residual gas (Shevelko et al., 2009).
... through Rutherford scattering.
... through radiative recombination at cooling conditions. Calculated from Bethe-Salpeter formula.