A Tour of HepSim From a User’s Perspective

David Blyth - Postdoc - ANL (HEP)

What is HepSim?

• A simple but powerful tool for building a “Repository with MC simulations for particle physics”
• Consists of a web interface and command-line tools
• Already contains ~2 Billion events
• LO+PS, NLO, and NLO+PS
• Environment to study detector effects with fast and full simulations
• Platform that continues to evolve
• NOT a storage service
• Files are hosted where convenient, and linked to by HepSim

Why HepSim?

• Began at Snowmass 2013
• Open access
• No authentication for use of sample sets
• Grab samples with hs-toolkit, wget, curl, etc… your choice!
• Preservation and publication of MC samples and simulated data
• Cache for iterative experiment design process
• Comparison with experimental data

Recreated figure originally by

W. Armstrong

Logical organization of HepSim

Web Interface

Web Interface - Truth Level Navigation

Web Interface - Truth Level Navigation

Select by beam species, CM energy, and

topic (SM, Exotic, etc)

Web Interface - Truth Level Navigation

Choose dataset based on generator and process descriptions

Then click on data set name to look at more closely

Web Interface - Truth Level Navigation

This brings up information page for dataset. Starting with basic parameters, integrated luminosity, and a link to the download page

Web Interface - Truth Level Navigation

Simulation tags

Web Interface - Truth Level Navigation

Event generator details

Web Interface - Truth Level Navigation

Validation

Web Interface - Truth Level Navigation

hs-toolkit helper command

Direct HTTP download links

Web Interface - Simulation Tag Navigation

Under tools, click RecoTags

Web Interface - Simulation Tag Navigation

Navigate by detector and/or experiment

Web Interface - Simulation Tag Navigation

Use Info link to learn more about a tag

Web Interface - Simulation Tag Navigation

From here, detector information and a list of simulated/reconstructed datasets can be found

Dataset list

Web Interface - Simulation Tag Navigation

Click on a link highlighted in yellow

Web Interface - Truth Level Navigation

Note that hs-toolkit command is now tagged

Web Interface - Detector

Web Interface - Detector

JSROOT Visualization

Geometry in various formats

Web Interface - Detector Visualization

Web Interface - Detector Visualization

hs-toolkit

hs-toolkit - Download and setup

hs-toolkit - Get truth-level files with hs-get

NAME

OUTPUT DIR

NUM THREADS

NUM FILES

hs-toolkit - Examine truth-level files with hs-info

hs-toolkit - Graphically examine truth-level files with hs-view

hs-toolkit - Simulate pileup with hs-pileup

hs-toolkit - Find and get simulation/reconstruction files with hs-find and hs-get

hs-toolkit - Run validation python scripts with hs-run

hs-toolkit - Run validation python scripts with hs-run

How my work uses HepSim

• EIC experiment design
• Development of simulation and reconstruction software chain
• Using HepSim’s truth-level samples as input
• Produce simulated/reconstructed samples at key points as software chain evolves
• HepSim simulation tags serve as a means to distribute and organize samples within research group
• Detector geometry iteration
• Using HepSim’s truth-level samples as input
• Each geometry iteration is documented with simulation tags
• Research group collaboratively assesses change in detector performance by referencing tags

Near-future HepSim developments

• Better argument handling in hs-toolkit
• Associating simulation/reconstruction tags with container image tags
• Provide the ability to exactly reproduce tag datasets
• Snapshot of all software and parameters that went into producing a tag

Thanks!

For more information, please see the HepSim web manual and hs-help on the command line.

​

HepSim contributors:

http://atlaswww.hep.anl.gov/hepsim/doc/doku.php?id=hepsim:contributions