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Manuscript Title: The DEPOSIT computer code: calculations of electron-loss cross sections for complex ions colliding with neutral atoms.
Authors: Mikhail S. Litsarev
Program title: DEPOSIT
Catalogue identifier: AENP_v1_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 184(2013)432
Programming language: C++.
Computer: Any computer that can run C++ compiler.
Operating system: Any operating system that can run C++.
Has the code been vectorised or parallelized?: An MPI version is included in the distribution.
Keywords: Cross-section, Ion-atom collisions, Electron-loss, Deposited energy, Impact parameter, Slater wave function.
PACS: 34.50.Fa, 34.50.Bw.
Classification: 2.4, 2.6, 4.10, 4.11.

Nature of problem:
For a given impact parameter b to calculate the deposited energy T(b) as a 3D integral over a coordinate space, and ionization probabilities Pm(b).
For a given energy to calculate the total and m-fold electron-loss cross sections using T(b) values.

Solution method:
Direct calculation of the 3D-integral T(b).
One-dimension quadrature formula of the highest accuracy based upon the nodes of the Yacobi polynomials for the cosθ = x ∈ [-1, 1] angular variable is applied. The Simpson rule for the φ ∈ [0, 2π] angular variable is used. Newton-Cotes pattern of the seventh order embedded into every segment of the logarithmic grid for the radial variable r ∈ [0, ∞] is applied. Clamped cubic spline interpolation is done for the integrand of the T(b).
Bisection method and further parabolic interpolation is applied for the solving of the nonlinear equation for the total cross-section. The Simpson rule for the m-fold crosssection calculation is applied.

Running time:
For a given energy, the total and m-fold cross sections are calculated within about 15 minutes on 8-core system. The running time is directly proportional to the number of cores.