FCC-ee optics repository
The FCC-ee optics and data repository holds data and optics files for a number of beam dynamics studies under way to design the FCC-ee collider.
This includes lattice files detailing the layout of the machine and the optics, as well as files containing numerous parameters associated with each operation mode.
Accessing and referencing the repository
The repository can be found under this link.
The data can also be found on /afs/cern.ch/eng/acc-models/fccee and on /eos/project/a/acc-models/public/fcc/fccee.
Following the mandated regulations of the Horizon 2020 research and innovation programme, the repository and its files are available without any access restriction.
Following certain project milestones, a snapshot of the repository will be tagged with a version number, and a reference for publication including a DOI will be provided via Zenodo.
Structure
Only a few files are located at the top level of the repository, mostly for administration of the repository itself.
Most important are README.md that serves as a quick introduction and orientation guide, the CHANGELOG.md for a running count of changes, and reference_parameters.json that contains the reference set of machine parameters for each operation mode, such as the beam energy, tunes, number of bunches and bunch population.
Most users will find the necessary files in the directories below.
lattices
This directory holds the lattice files for the different operation modes of the collider.
aperture
In this directory, files required for collimation related studies, such as aperture files, are stored.
toolkit
Commonly functions and subroutines are put in this folder.
web
Contains scripts and templates for deploying the information to the Acc-Models website.
test
To check that the models and parameter set stay consistent after changes, a number scripts are kept that here and are run after each change and report in case of inconsistencies.
Development
The version control system of GIT is used, and is centrally managed by a gitlab instance hosted at CERN.
Major milestones in the development of the FCC-ee lattices will be marked with a version.
The current state of the repository will be saved, and available under Tags in GIT, or alternatively on Zenodo, where a DOI will be attached to the version.
The following scheme for versioning is used VYY.idx, where
- YY is the year in which the first version is released
- and idx a running index to distinguish between minor updates.
For each released version, where the identifier VYY is versioned, a separate branch is created and protected, that is, only maintainers can perform any change on this branch.
This branch will contain the latest version (latest idx) including potentially unreleased changes.
For contributors
Contributors are encouraged to create a separate branch to contribute their own work to the repository and refrain from modifying the main branches.
Contributor branches should be named after the released version that serves as the basis (target branch) with an additional descriptor to facilitate the organisation: VYY_description
To merge the changes into the target branch, a merge request shall be created. This will trigger a review and approval process by maintainers. Once all checks are passed, the changes will be integrated in the target branch.
In case of any question or problem, please do not hesistate to contact FCC.Optics@cern.ch.