Skip to content

Combine v11, ready for CERN SWAN

A pinned, isolated notebook environment for running CMS Combine without replacing SWAN's own Python stack.

Start on SWAN See the verified notebook

Combinev11.0.0
CMSSWCMSSW_16_0_0
Architectureel9_amd64_gcc13
Kernelcombine-v11

The short path

Download the project from Git in SWAN:

https://github.com/DickyChant/combine_swan_integration.git

Then open a terminal in the checkout and run:

./install.sh

The installer creates the complete CMSSW area at:

<repository checkout>/CMSSW_16_0_0

Refresh JupyterLab, open the supplied notebook, and select:

Python 3 (CMSSW_16_0_0 + Combine v11.0.0)

For later sessions, configure the repository's swan_env.sh as the SWAN Environment script. The setup guide walks through this once, including the kernel-picker restart behavior.

What is isolated

The parent SWAN notebook server keeps its selected LCG Python and libraries. Only the dedicated Combine kernel activates CMSSW. This boundary prevents the two Python stacks from contaminating each other while keeping both available in the same SWAN project.

flowchart LR
    A[SWAN server<br/>LCG Python] --> B[combine-v11<br/>kernel launcher]
    B --> C[CMSSW_16_0_0<br/>PyROOT + ipykernel]
    C --> D[Combine v11.0.0]

Verified on SWAN

Reference execution: 1 August 2026. The committed notebook imports PyROOT and HiggsAnalysis.CombinedLimit, checks the exact Combine tag, exercises the main command-line tools, and completes a blind AsymptoticLimits run that produces a non-empty ROOT file.

That is an installation and runtime validation. It does not independently validate a user's physics model, datacard, nuisance model, or statistical interpretation. See Validation for the exact boundary.

Choose your next step