Dose levels at the SPS, monitoring and calculation. Oliver Stein (EN-EA)

Radiation monitoring at the SPS Questions: What is the dose in the SPS tunnel at specific positions (dcum,x,y)? What is the expected dose? Where are the hot spots? Installed detectors: 268 BLMs active RadMons active RadFets passive RPLs passive Can we calculate the dose in the tunnel? by using available data sets

BLMs in the SPS BLMs are actively logged in the LDB. Data Grays/cycle Data extracted for 2016 Data weekly summed Data volume is much smaller than the LHC BLM data Comparison with 2015/2012 ongoing Data of the SPS BLMs, summed for 2016 + SPS layout LSS 1 LSS 2 LSS 3 LSS 4 LSS 5 LSS 6

BLMs in the SPS Regular FODO structure in the arc sections. Simulation of one FODO sufficient? Distance functions For straight section more detailed models necessary! FLUKA simulation for LSS 2 ongoing FODO structure Dipoles Quad Defocus Quad Focus

SPS dose calculation Calculating the dose from interpolated BLM data and distance models. RadFets RadMon BLM Functions (dcum,x,y) FLUKA Other… Other Interpolation Distance Models Data extraction Interpolation Distance models Distance functions Error function Dose in the tunnel + uncertainties  Dose maps of the SPS tunnel Dose (dcum,x,y)

SPS dose calculation plan and status Python frame work BLM data included Interpolation of BLM data Distance Models Simple distance function (dcum,x,y)  SPS layout used for segmentation FLUKA models  SPS LSS 2 simulation ongoing Calculation of uncertainties More sophisticated functions/models Testing Stability of the models  Influence of optics changes, layout, etc. Comparison with non included data Dose resolution limits Spatial resolution, details Time estimation: 2 Month +

Very simple model, exemplary visualization SPS dose calculation First examples: SPS dose map for dcum 0 to 200 at y = 0 Very simple model, exemplary visualization

Very simple model, exemplary visualization SPS dose calculation First examples: Very simple model, exemplary visualization

SPS dose calculation First examples: Very simple distance functions: 1/r2 Used layout for defining regions with different distance functions (scaled) Magnets shield the radiation Drifts sections shield less More input for models needed. Lorentz boost not included yet. SPS dose map for dcum 0 to 200 at y = 0 Very simple model, exemplary visualization

Goals: Creating a “modular tool box” for calculating the dose in the SPS tunnel. Dose estimations with uncertainties for all positions of the SPS tunnel. Continuous benchmarking with new measurements and simulations. Optimisation of the existing models. Questions: Shall we continue? Who is participating?

Thank you!