Speaker
Description
MARS15 Code Status and Path Forward
Nikolai V. Mokhov
1Fermi National Accelerator Laboratory, Batavia, IL 60510, USA
mokhov@fnal.gov
Abstract
The MARS15 multi-purpose Monte-Carlo code is Fermilab’s particle-matter interaction code that supports the lab’s projects along with numerous accelerator facilities in the country and abroad at all stages, from planning and design to operations and decommissioning. The MARS group is involved in the design and upgrades of the high-power targets, beamlines, collimators, absorbers, and experimental flagship facilities at Fermilab, such as LBNF, PIP-II, and mu2e, as well as the MI-8, Delivery Ring, and Booster upgrades, along with detailed modeling of the crucial aspects of future projects such as a Muon Collider. Besides all of these applications, the group’s activities are currently focused on the code developments in the following areas: (1) increased physics output by maximizing useful particle yields from target systems and minimizing backgrounds in detectors; (2) modeling of 3D distributions of particle flux, energy deposition density, prompt and residual doses, nuclide production, radiation damage, and spectra by primary and secondary beams for complex accelerator and detector configurations; (3) optimized performance of predictive virtual particle accelerators and experimental setups (e.g., MARSLBNF); (4) safe designs and operations of accelerator systems and experiments; (5) making MARS even more capable, trustable and usable in practically arbitrary parameter phase space; (6) further development of the SRF modules including detailed underlying physics; (7) creation of the CAD MARS_ROOT CAD user-friendly geometry converters compatible with strict requirements for particle-matter simulation in a challenging accelerator environment.
A MARS geometry model can be imported from a CAD model, converted from a corresponding mesh generated for ANSYS calculations, or created via bilateral geometry model exchange with Geant4 directly using GDML format, with every stage verified using an advanced 3D GUI. The further improved powerful integrated MARS-MADX-PTC system is highly efficient for particle tracking in SRF (with time-dependent electromagnetic fields and Dark Current production), quadrupole, dipole, solenoid magnets, and Machine-Detector Interface (MDI) for use in the 10-5 eV < E < 100 TeV energy range. Further near-term plans include: (1) implementation of modern code-management techniques; (2) perfection of codebase (Fortran & C++, Hbook & ROOT histograms etc.); (3) improve MPI mode to minimize a loss in scalability with a number of MPI ranks > 4×104 on the current petaflop (1015 fpo/s) platform and prepare for the exascale (1018 fpo/s) computing era.