# \#hep

**URL:** https://discourse.julialang.org/tag/hep/467.md

[Latest](https://discourse.julialang.org/latest.md) · [Categories](https://discourse.julialang.org/categories.md) · [Tags](https://discourse.julialang.org/tags.md)

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## [Connection between BFGS and ROOT.Minuit. Stopping criteria](https://discourse.julialang.org/t/connection-between-bfgs-and-root-minuit-stopping-criteria/48729)

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**Author:** [@misha\_mikhasenko](https://discourse.julialang.org/u/misha_mikhasenko)\
**Replies:** 9\
**Last updated:** [August 11, 2026, 8:00am UTC](https://discourse.julialang.org/t/connection-between-bfgs-and-root-minuit-stopping-criteria/48729 "2026-08-11T08:00:01Z")

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Dear experts on optimization problems, I am trying to establish a connection between the common tools in High Energy Physics (HEP) and Julia ecosystem. In HEP, the main tool for optimization is Minuit library. Nowadays…

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## [Julia for HEP now available via CVMFS](https://discourse.julialang.org/t/julia-for-hep-now-available-via-cvmfs/129737)

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**Author:** [@oschulz](https://discourse.julialang.org/u/oschulz)\
**Replies:** 5\
**Last updated:** [June 9, 2025, 11:48am UTC](https://discourse.julialang.org/t/julia-for-hep-now-available-via-cvmfs/129737 "2025-06-09T11:48:56Z")

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I’m happy to announce that we now have a HEP (particle physics) Julia distribution available via CVMFS (thanks for all the friendly help here!). Two container images registry.cern.ch/juliahep/juliahep-core:latest: A …

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## [Problem reading ROOT branch containing Strings with UnROOT.jl](https://discourse.julialang.org/t/problem-reading-root-branch-containing-strings-with-unroot-jl/115671)

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**Author:** [@GSavvidis](https://discourse.julialang.org/u/GSavvidis)\
**Replies:** 7\
**Last updated:** [June 18, 2024, 7:19am UTC](https://discourse.julialang.org/t/problem-reading-root-branch-containing-strings-with-unroot-jl/115671 "2024-06-18T07:19:47Z")

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Hello, I’m using Geant4 to simulate some decays and I’m saving the result in a root file which I then read with UnROOT.jl. I have the following code: using DrWatson quickactivate(@\_\_DIR\_\_) using UnROOT f = UnROOT.ROO…

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## [Reading ROOT file with Branches](https://discourse.julialang.org/t/reading-root-file-with-branches/112014)

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**Author:** [@Fourier](https://discourse.julialang.org/u/Fourier)\
**Replies:** 3\
**Last updated:** [March 23, 2024, 8:27pm UTC](https://discourse.julialang.org/t/reading-root-file-with-branches/112014 "2024-03-23T20:27:16Z")

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I have a root file with a tree, branches and leaves, like this: When I try to read it like using UnROOT like this: using UnROOT f = ROOTFile("out\_files/pienu00000-00.root") tree = LazyTree(f,"sim") I get a bounds …

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## [Storing and accessing large jagged array with julia](https://discourse.julialang.org/t/storing-and-accessing-large-jagged-array-with-julia/45973)

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**Author:** [@Luapulu](https://discourse.julialang.org/u/Luapulu)\
**Replies:** 33\
**Last updated:** [October 31, 2023, 11:10am UTC](https://discourse.julialang.org/t/storing-and-accessing-large-jagged-array-with-julia/45973 "2023-10-31T11:10:50Z")

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I have a bunch of data, currently stored in 2000 seperate .csv files. Each file countains thousands of events, where each event starts with three numbers, one of which specifies the length of the event. All following row…

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## [Julia potential for high energy physics computing](https://discourse.julialang.org/t/julia-potential-for-high-energy-physics-computing/99992)

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**Author:** [@grasph](https://discourse.julialang.org/u/grasph)\
**Replies:** 3\
**Last updated:** [October 6, 2023, 9:50am UTC](https://discourse.julialang.org/t/julia-potential-for-high-energy-physics-computing/99992 "2023-10-06T09:50:11Z")

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Hello, On behalf of its authors, I would like to announce the following preprint released last night, Potential of the Julia programming language for high energy physics computing, J. Eschle et al., arXiv:2306.03675 T…

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## [Issues with foreign threads calling back Julia and GC](https://discourse.julialang.org/t/issues-with-foreign-threads-calling-back-julia-and-gc/104384)

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**Author:** [@peremato](https://discourse.julialang.org/u/peremato)\
**Replies:** 11\
**Last updated:** [September 29, 2023, 6:06pm UTC](https://discourse.julialang.org/t/issues-with-foreign-threads-calling-back-julia-and-gc/104384 "2023-09-29T18:06:31Z")

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In the Geant4.jl project I am wrapping a large C++ library that supports multi-threading for tracking particles through matter. I have found an almost working solution by disabling the GC, but if the run is very long, …

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## [JuliaHEP Workshop 2023 at Erlangen Centre for Astroparticle Physics](https://discourse.julialang.org/t/juliahep-workshop-2023-at-erlangen-centre-for-astroparticle-physics/102591)

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**Author:** [@tamasgal](https://discourse.julialang.org/u/tamasgal)\
**Replies:** 0\
**Last updated:** [August 8, 2023, 6:28am UTC](https://discourse.julialang.org/t/juliahep-workshop-2023-at-erlangen-centre-for-astroparticle-physics/102591 "2023-08-08T06:28:54Z")

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Hi folks! The first ever Julia HEP Workshop is open for registrations and we are eagerly awaiting your abstracts for talks and tutorials. It will be a four day long hybrid event from 6-9th November 2023 hosted at the E…

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## [Paper on Julia portiential for HEP](https://discourse.julialang.org/t/paper-on-julia-portiential-for-hep/99994)

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**Author:** [@grasph](https://discourse.julialang.org/u/grasph)\
**Replies:** 0\
**Last updated:** [June 7, 2023, 9:36am UTC](https://discourse.julialang.org/t/paper-on-julia-portiential-for-hep/99994 "2023-06-07T09:36:14Z")

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Please note, this announcement on the release of the preprint of an important paper: Julia potential for high energy physics computing. Questions and follow-up can be done here.

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## [How to correctly design multi-thread cache that's transparent to user iteration?](https://discourse.julialang.org/t/how-to-correctly-design-multi-thread-cache-thats-transparent-to-user-iteration/99577)

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**Author:** [@jling](https://discourse.julialang.org/u/jling)\
**Replies:** 10\
**Last updated:** [May 31, 2023, 7:18am UTC](https://discourse.julialang.org/t/how-to-correctly-design-multi-thread-cache-thats-transparent-to-user-iteration/99577 "2023-05-31T07:18:16Z")

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Runnable code and benchmark at this gist. This is a widespread pattern for columnar-storage access, usually each column is too large to fit in ram, so it’s chunked in to clusters, and each cluster is individually compre…

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## [Lorentz Vector reusability for QED.jl (event generator)](https://discourse.julialang.org/t/lorentz-vector-reusability-for-qed-jl-event-generator/95871)

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**Author:** [@jling](https://discourse.julialang.org/u/jling)\
**Replies:** 2\
**Last updated:** [March 10, 2023, 11:54pm UTC](https://discourse.julialang.org/t/lorentz-vector-reusability-for-qed-jl-event-generator/95871 "2023-03-10T23:54:13Z")

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I was watching in awe of https://www.youtube.com/watch?v=BqRps2dwLxE by @szabo137. Afterwards @peremato asked one of the questions I had which is why not re-use some of the existing JuliaHEP stuff, simplest example being…

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## [Julia @ IN2P3-FR Computing center (CCINP3)](https://discourse.julialang.org/t/julia-in2p3-fr-computing-center-ccinp3/90813)

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**Author:** [@grasph](https://discourse.julialang.org/u/grasph)\
**Replies:** 13\
**Last updated:** [November 30, 2022, 12:38pm UTC](https://discourse.julialang.org/t/julia-in2p3-fr-computing-center-ccinp3/90813 "2022-11-30T12:38:40Z")

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Hello, We are working on setting up a Julia environment at the French IN2P3 computing center. Note: These resources are available to HEP physicists from French institutes with an account at the center. What is availa…

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## [Allocation and slow down when # of types involved increase (slower than C++ virtual methods)](https://discourse.julialang.org/t/allocation-and-slow-down-when-of-types-involved-increase-slower-than-c-virtual-methods/87656)

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**Author:** [@jling](https://discourse.julialang.org/u/jling)\
**Replies:** 56\
**Last updated:** [November 9, 2022, 7:38pm UTC](https://discourse.julialang.org/t/allocation-and-slow-down-when-of-types-involved-increase-slower-than-c-virtual-methods/87656 "2022-11-09T19:38:33Z")

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\*Happy to pay someone to spend time investigating this The context is @peremato trying to present a Julia case for detector simulation used at e.g. CERN (the LHC) and other accelerator/medical research places: https://in…

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## [Call for contribution to a Julia version of HEP Software Foundation Tutorials](https://discourse.julialang.org/t/call-for-contribution-to-a-julia-version-of-hep-software-foundation-tutorials/84784)

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**Author:** [@jling](https://discourse.julialang.org/u/jling)\
**Replies:** 0\
**Last updated:** [July 26, 2022, 2:31am UTC](https://discourse.julialang.org/t/call-for-contribution-to-a-julia-version-of-hep-software-foundation-tutorials/84784 "2022-07-26T02:31:17Z")

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The goal is to provide similar tutorials as listed at: HSF Software Training Center Currently we have covered the uproot tutorial (lacking detail commentary atm) I have started a repo with setup CI + Pluto static build…

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## [How to organize loop with long prologue and epilogue that switches depending on task](https://discourse.julialang.org/t/how-to-organize-loop-with-long-prologue-and-epilogue-that-switches-depending-on-task/76566)

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**Author:** [@jling](https://discourse.julialang.org/u/jling)\
**Replies:** 12\
**Last updated:** [February 16, 2022, 8:35pm UTC](https://discourse.julialang.org/t/how-to-organize-loop-with-long-prologue-and-epilogue-that-switches-depending-on-task/76566 "2022-02-16T20:35:16Z")

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imagine the main loop boils down to this: function main(table) # prologue: 30 lines to set up result for r in table # 400 lines to filter and make composite variable # epilogue: 30 lines to fill variable …

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## [About the High Energy Physics category](https://discourse.julialang.org/t/about-the-high-energy-physics-category/69015)

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**Author:** [@mbauman](https://discourse.julialang.org/u/mbauman)\
**Replies:** 0

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Discussion about use of Julia in High energy and nuclear physics. Related git organization: https://github.com/JuliaHEP Please include the “hep” tag when creating a topic.

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## [Julia for HEP Mini-workshop](https://discourse.julialang.org/t/julia-for-hep-mini-workshop/68622)

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**Author:** [@giordano](https://discourse.julialang.org/u/giordano)\
**Replies:** 1\
**Last updated:** [September 23, 2021, 12:37pm UTC](https://discourse.julialang.org/t/julia-for-hep-mini-workshop/68622 "2021-09-23T12:37:22Z")

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Following up the Julia session at the last PyHEP workshop, a study of potential of this programming language for HEP is being launched within the PyHEP WG of HSF. The goal is to write a report that will describe its pot…

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## [\[ANN\] Announcing AlgebraPDF.jl - operations on functions with parameters](https://discourse.julialang.org/t/ann-announcing-algebrapdf-jl-operations-on-functions-with-parameters/65213)

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**Author:** [@misha\_mikhasenko](https://discourse.julialang.org/u/misha_mikhasenko)\
**Replies:** 12\
**Last updated:** [July 25, 2021, 8:53pm UTC](https://discourse.julialang.org/t/ann-announcing-algebrapdf-jl-operations-on-functions-with-parameters/65213 "2021-07-25T20:53:44Z")

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Hi, I am happy to announce AlgebraPDF.jl, a package that defines operations on parametric functions and keeps track of parameters. f1 = FunctionWithParameters((x;p)-\>cos(p.a\*x+p.b), (a=5.0, b=2.0)) f2 = FunctionWithPar…

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## [Vertical errors for historgrams](https://discourse.julialang.org/t/vertical-errors-for-historgrams/45881)

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**Author:** [@misha\_mikhasenko](https://discourse.julialang.org/u/misha_mikhasenko)\
**Replies:** 2\
**Last updated:** [September 1, 2020, 9:27am UTC](https://discourse.julialang.org/t/vertical-errors-for-historgrams/45881 "2020-09-01T09:27:06Z")

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In my field of research (HEP), the vertical errors for the histograms are widely used. Usually, they are calculated assuming narrow bins and Poisson distribution for the number of entries, i.e. the error is sqrt(Nentri…