# Issues **URL:** https://allpix-squared-forum.web.cern.ch/c/issues/5.md [Latest](https://allpix-squared-forum.web.cern.ch/latest.md) · [Categories](https://allpix-squared-forum.web.cern.ch/categories.md) --- ## [About the Issues category](https://allpix-squared-forum.web.cern.ch/t/about-the-issues-category/18)
**Author:** [@simonspa](https://allpix-squared-forum.web.cern.ch/u/simonspa)\ **Replies:** 0
Category to discuss issues with the framework, potential bugs or unexpected behavior --- ## [Hanging of mesh convertion](https://allpix-squared-forum.web.cern.ch/t/hanging-of-mesh-convertion/59)
**Author:** [@Sinuo](https://allpix-squared-forum.web.cern.ch/u/Sinuo)\ **Replies:** 2\ **Last updated:** [October 1, 2026, 3:46pm UTC](https://allpix-squared-forum.web.cern.ch/t/hanging-of-mesh-convertion/59 "2026-10-01T15:46:21Z")
Dear maintainers, I have currently found a problem while converting TCAD mesh to allpix2 readable format via “mesh\_converter”. Namely, the converting process has been proceeding for \>20h on 12 cores for a 2D mesh witho… --- ## [Possible issue in RungeKutta::step() stage-time calculation](https://allpix-squared-forum.web.cern.ch/t/possible-issue-in-rungekutta-step-stage-time-calculation/819)
**Author:** [@rickard](https://allpix-squared-forum.web.cern.ch/u/rickard)\ **Replies:** 4\ **Last updated:** [August 5, 2026, 7:49am UTC](https://allpix-squared-forum.web.cern.ch/t/possible-issue-in-rungekutta-step-stage-time-calculation/819 "2026-08-05T07:49:55Z")
Hi all, I am sitting trying to implement a fully coupled RK with Coulomb forces and noticed in the step function of runge\_kutta.h something I can’t quite understand, due it being a RungeKutta utility with a derivative t… --- ## [Bugfix InteractivePropagation module](https://allpix-squared-forum.web.cern.ch/t/bugfix-interactivepropagation-module/807)
**Author:** [@Jurgen](https://allpix-squared-forum.web.cern.ch/u/Jurgen)\ **Replies:** 1\ **Last updated:** [July 26, 2026, 6:35am UTC](https://allpix-squared-forum.web.cern.ch/t/bugfix-interactivepropagation-module/807 "2026-07-26T06:35:10Z")
Hi, Recently I have been working with the InteractiveModule from Draft: New Module: InteractivePropagationModule by gkunkler · Pull Request #53 · allpix-squared/all… First of all, many thanks to the creator of this mod… --- ## [Missing #include \ in DetectorHistogrammerModule.cpp](https://allpix-squared-forum.web.cern.ch/t/missing-include-numbers-in-detectorhistogrammermodule-cpp/802)
**Author:** [@jburvill](https://allpix-squared-forum.web.cern.ch/u/jburvill)\ **Replies:** 1\ **Last updated:** [June 23, 2026, 2:36pm UTC](https://allpix-squared-forum.web.cern.ch/t/missing-include-numbers-in-detectorhistogrammermodule-cpp/802 "2026-06-23T14:36:49Z")
In trying to compile allpix-squared on my MacOS from source, I kept running into the following error: /src/modules/DetectorHistogrammer/DetectorHistogrammerModule.cpp:447:71: error: no member named ‘numbers’ in namespac… --- ## [DepositionGeant4 output plots missing part of sensor incidences](https://allpix-squared-forum.web.cern.ch/t/depositiongeant4-output-plots-missing-part-of-sensor-incidences/792)
**Author:** [@sake](https://allpix-squared-forum.web.cern.ch/u/sake)\ **Replies:** 0\ **Last updated:** [March 17, 2026, 2:25pm UTC](https://allpix-squared-forum.web.cern.ch/t/depositiongeant4-output-plots-missing-part-of-sensor-incidences/792 "2026-03-17T14:25:02Z")
I am using the data of the output plots of the DepositionGeant4 module in modules.root to get acquainted with allpix squared and root. Setup: A timepix detector (mydetector) with a 256 x 256 pixel matrix with 55um x 55… --- ## [Memory leak when assigning AP2 vectors to branches in PyROOT examples](https://allpix-squared-forum.web.cern.ch/t/memory-leak-when-assigning-ap2-vectors-to-branches-in-pyroot-examples/486)
**Author:** [@ggiakous](https://allpix-squared-forum.web.cern.ch/u/ggiakous)\ **Replies:** 5\ **Last updated:** [February 23, 2026, 9:54am UTC](https://allpix-squared-forum.web.cern.ch/t/memory-leak-when-assigning-ap2-vectors-to-branches-in-pyroot-examples/486 "2026-02-23T09:54:32Z")
Hi Allpix Squared team, I am a new user and I am working on simulating an x-ray tube. The framework is easy to understand and use, so, many thanks for this!!! At the moment I am facing some troubles with analyzing the … --- ## [Multithread not working: analyze the output root file with multi-thread](https://allpix-squared-forum.web.cern.ch/t/multithread-not-working-analyze-the-output-root-file-with-multi-thread/753)
**Author:** [@weiy](https://allpix-squared-forum.web.cern.ch/u/weiy)\ **Replies:** 4\ **Last updated:** [June 11, 2025, 7:09am UTC](https://allpix-squared-forum.web.cern.ch/t/multithread-not-working-analyze-the-output-root-file-with-multi-thread/753 "2025-06-11T07:09:45Z")
Dear experts, I would like to process the root file generated from allpix using multithreading. But it turns out that I couldn’t make it properly. Could you help me take a look at my code? I have two scripts (but it to… --- ## [Mesh\_converter: core dump but file created](https://allpix-squared-forum.web.cern.ch/t/mesh-converter-core-dump-but-file-created/738)
**Author:** [@mbomben](https://allpix-squared-forum.web.cern.ch/u/mbomben)\ **Replies:** 0\ **Last updated:** [May 13, 2025, 6:08am UTC](https://allpix-squared-forum.web.cern.ch/t/mesh-converter-core-dump-but-file-created/738 "2025-05-13T06:08:46Z")
Dear all, I am using v3.0.2 to convert electric field 3D map from Silvaco TCAD into init format. Despite the init file being correctly created and saved I got this error at the end of the mesh\_converter job: |07:59:39… --- ## [Using uproot to read large root file and access PixelCharge/MCParticle](https://allpix-squared-forum.web.cern.ch/t/using-uproot-to-read-large-root-file-and-access-pixelcharge-mcparticle/716)
**Author:** [@Linus](https://allpix-squared-forum.web.cern.ch/u/Linus)\ **Replies:** 1\ **Last updated:** [March 27, 2025, 9:44pm UTC](https://allpix-squared-forum.web.cern.ch/t/using-uproot-to-read-large-root-file-and-access-pixelcharge-mcparticle/716 "2025-03-27T21:44:27Z")
Hi, I have been trying to read PixelCharge, MCParticle data from a root file into python. I am analysing a large number of events, on the order of a million, at a setup of 6 Timepix detectors. The method provided as a… --- ## [Simulation filling up memory until it gets killed](https://allpix-squared-forum.web.cern.ch/t/simulation-filling-up-memory-until-it-gets-killed/690)
**Author:** [@StefanGohl](https://allpix-squared-forum.web.cern.ch/u/StefanGohl)\ **Replies:** 10\ **Last updated:** [January 20, 2025, 5:17pm UTC](https://allpix-squared-forum.web.cern.ch/t/simulation-filling-up-memory-until-it-gets-killed/690 "2025-01-20T17:17:43Z")
Hello, I am simulating neutron measurements using a converter and then a standard 300um and 500 um timepix silicon detectors. The simulation was working fine until I switched from the \[GenericPropagation\] module to the … --- ## [Sensor excess value is not behaving as expected](https://allpix-squared-forum.web.cern.ch/t/sensor-excess-value-is-not-behaving-as-expected/694)
**Author:** [@rickard](https://allpix-squared-forum.web.cern.ch/u/rickard)\ **Replies:** 2\ **Last updated:** [January 16, 2025, 11:07am UTC](https://allpix-squared-forum.web.cern.ch/t/sensor-excess-value-is-not-behaving-as-expected/694 "2025-01-16T11:07:50Z")
Hi all, I am trying to simulate a sensor and want to use the sensor\_excess to set an amount of silicon in front of the active pixel area to get an appropriate filtering of the incoming x-ray spectra. However, when I try… --- ## [Disappearing charge carriers, missing collected charge carriers, and too wide charge clouds,](https://allpix-squared-forum.web.cern.ch/t/disappearing-charge-carriers-missing-collected-charge-carriers-and-too-wide-charge-clouds/683)
**Author:** [@rickard](https://allpix-squared-forum.web.cern.ch/u/rickard)\ **Replies:** 8\ **Last updated:** [January 15, 2025, 12:25pm UTC](https://allpix-squared-forum.web.cern.ch/t/disappearing-charge-carriers-missing-collected-charge-carriers-and-too-wide-charge-clouds/683 "2025-01-15T12:25:39Z")
Hi all, This is going to be a bit long, and is separated into 3 parts. I am simulating a detector, similar in geometry to the one simulated here by Sundberg et al.: 1-μm spatial resolution in silicon photon-counting C… --- ## [MCParticle vs MCtrack energies](https://allpix-squared-forum.web.cern.ch/t/mcparticle-vs-mctrack-energies/628)
**Author:** [@luca\_tero](https://allpix-squared-forum.web.cern.ch/u/luca_tero)\ **Replies:** 18\ **Last updated:** [November 26, 2024, 5:33pm UTC](https://allpix-squared-forum.web.cern.ch/t/mcparticle-vs-mctrack-energies/628 "2024-11-26T17:33:53Z")
Hi, For my purpose i need to retrieve the true interactions positions of gamma rays interacting with a silicon detector as well as the deposited energies. For this reason i was playing around with MCTrack and MCParticle… --- ## [Odd behaviour of the weighting potential](https://allpix-squared-forum.web.cern.ch/t/odd-behaviour-of-the-weighting-potential/631)
**Author:** [@rickard](https://allpix-squared-forum.web.cern.ch/u/rickard)\ **Replies:** 12\ **Last updated:** [November 18, 2024, 6:46pm UTC](https://allpix-squared-forum.web.cern.ch/t/odd-behaviour-of-the-weighting-potential/631 "2024-11-18T18:46:09Z")
Hi again! I am unsure the category is correct, but it is what it is I guess. The problem I am having is that the weighting potential is showing gaps when I plot it. Given that the weighting potential is plotted for pix… --- ## [Error Loading GDML from Geant4](https://allpix-squared-forum.web.cern.ch/t/error-loading-gdml-from-geant4/672)
**Author:** [@Tim](https://allpix-squared-forum.web.cern.ch/u/Tim)\ **Replies:** 1\ **Last updated:** [November 12, 2024, 4:41pm UTC](https://allpix-squared-forum.web.cern.ch/t/error-loading-gdml-from-geant4/672 "2024-11-12T16:41:30Z")
Hey there, im quite new to Allpix and im trying to load in a geometry created in Geant4 without success. Im creating the gdml in my Geant4 Simulation like this: G4GDMLParser parser; parser.Write("Test.gdml", logicWorl… --- ## [Physics list Shielding not 'valid'](https://allpix-squared-forum.web.cern.ch/t/physics-list-shielding-not-valid/624)
**Author:** [@StefanGohl](https://allpix-squared-forum.web.cern.ch/u/StefanGohl)\ **Replies:** 2\ **Last updated:** [September 4, 2024, 11:28am UTC](https://allpix-squared-forum.web.cern.ch/t/physics-list-shielding-not-valid/624 "2024-09-04T11:28:42Z")
Hello, I am trying to run an allpix squared simulation version 3.1.0 with the Shielding physics list. I get an error telling me that ‘Shielding’ does not exist and it gives me a list of available physics lists that incl… --- ## [Creation Process name VS ID mismatch (?)](https://allpix-squared-forum.web.cern.ch/t/creation-process-name-vs-id-mismatch/598)
**Author:** [@luca\_tero](https://allpix-squared-forum.web.cern.ch/u/luca_tero)\ **Replies:** 5\ **Last updated:** [August 19, 2024, 10:23am UTC](https://allpix-squared-forum.web.cern.ch/t/creation-process-name-vs-id-mismatch/598 "2024-08-19T10:23:10Z")
Hi all i’m quite new to allpix and i was running through some examples, in this case the passive volume one. As i was looking at the output i noticed that both from the ROOT and .txt files the Creation process name (in … --- ## [Is there a way to build allpix without the need of externals?](https://allpix-squared-forum.web.cern.ch/t/is-there-a-way-to-build-allpix-without-the-need-of-externals/605)
**Author:** [@Tim](https://allpix-squared-forum.web.cern.ch/u/Tim)\ **Replies:** 2\ **Last updated:** [August 7, 2024, 10:53am UTC](https://allpix-squared-forum.web.cern.ch/t/is-there-a-way-to-build-allpix-without-the-need-of-externals/605 "2024-08-07T10:53:31Z")
Im currently trying to build allpix on an Ubuntu system but get denied acces to dowloading certain Files while building: CMake Error at /usr/share/cmake-3.22/Modules/ExternalData.cmake:1181 (message): Object MD5=8… --- ## [Can not deduce ROOT's C++ version from build flags](https://allpix-squared-forum.web.cern.ch/t/can-not-deduce-roots-c-version-from-build-flags/585)
**Author:** [@rickard](https://allpix-squared-forum.web.cern.ch/u/rickard)\ **Replies:** 3\ **Last updated:** [June 14, 2024, 5:19pm UTC](https://allpix-squared-forum.web.cern.ch/t/can-not-deduce-roots-c-version-from-build-flags/585 "2024-06-14T17:19:18Z")
Hi all, I am installing Allpix Squared on Ubuntu 22.04 LTS and I am having troubles having Allpix recognizing the C++ version of ROOT, even though I have thoroughly followed the steps in the installation guide. I have … --- ## [Ctest failed: Required regular expression not found](https://allpix-squared-forum.web.cern.ch/t/ctest-failed-required-regular-expression-not-found/587)
**Author:** [@rickard](https://allpix-squared-forum.web.cern.ch/u/rickard)\ **Replies:** 3\ **Last updated:** [June 14, 2024, 5:18pm UTC](https://allpix-squared-forum.web.cern.ch/t/ctest-failed-required-regular-expression-not-found/587 "2024-06-14T17:18:06Z")
Hi all, I have installed allpix squared with all of its prerequisites, as well as HEPMC3 and LCIO, but when running ctest the installation pass most of the test except for the following: The following tests FAILED: … --- ## [Effects of sensor\_resistivity](https://allpix-squared-forum.web.cern.ch/t/effects-of-sensor-resistivity/564)
**Author:** [@Fajer](https://allpix-squared-forum.web.cern.ch/u/Fajer)\ **Replies:** 1\ **Last updated:** [June 14, 2024, 1:04pm UTC](https://allpix-squared-forum.web.cern.ch/t/effects-of-sensor-resistivity/564 "2024-06-14T13:04:19Z")
Hello everyone, I hope you are doing well. I have a question regarding my simulation study. I am simulating HVCMOS sensors with a thickness of 300 μm. We have three chips with different resistivities, and we want to st… --- ## [Seeking Assistance with Allpix2 Mesh Converter and CPP File Compilation Issue](https://allpix-squared-forum.web.cern.ch/t/seeking-assistance-with-allpix2-mesh-converter-and-cpp-file-compilation-issue/571)
**Author:** [@Silvia](https://allpix-squared-forum.web.cern.ch/u/Silvia)\ **Replies:** 3\ **Last updated:** [May 19, 2024, 11:23pm UTC](https://allpix-squared-forum.web.cern.ch/t/seeking-assistance-with-allpix2-mesh-converter-and-cpp-file-compilation-issue/571 "2024-05-19T23:23:25Z")
Hello everyone, I am currently working with Allpix2, and I can run simulations without any issues. However, when I try to use certain tools, particularly the Mesh Converter, I encounter difficulties. Firstly, I’m tryin… --- ## [Installation error - Mac OS Sonoma](https://allpix-squared-forum.web.cern.ch/t/installation-error-mac-os-sonoma/561)
**Author:** [@hchu](https://allpix-squared-forum.web.cern.ch/u/hchu)\ **Replies:** 8\ **Last updated:** [May 14, 2024, 6:21pm UTC](https://allpix-squared-forum.web.cern.ch/t/installation-error-mac-os-sonoma/561 "2024-05-14T18:21:56Z")
While trying to install on Mac OS Sonoma, I met the error while building (‘make’ command) clang-13: error: \*\*linker command failed with exit code 1 (use -v to see invocation) I am installing it inside anaconda environm… --- ## [Something wrong in propagation progress, nothing could be got about gain](https://allpix-squared-forum.web.cern.ch/t/something-wrong-in-propagation-progress-nothing-could-be-got-about-gain/532)
**Author:** [@Nora](https://allpix-squared-forum.web.cern.ch/u/Nora)\ **Replies:** 26\ **Last updated:** [May 7, 2024, 7:27am UTC](https://allpix-squared-forum.web.cern.ch/t/something-wrong-in-propagation-progress-nothing-could-be-got-about-gain/532 "2024-05-07T07:27:17Z")
Hi, I find something strange in propagation progress. There is no gain information in the propagation progress. I guess maybe it is due to my electric filed. But I am not sure and do not know how to solve it. Could anyon… --- ## [Installation Error](https://allpix-squared-forum.web.cern.ch/t/installation-error/542)
**Author:** [@Sam\_username](https://allpix-squared-forum.web.cern.ch/u/Sam_username)\ **Replies:** 10\ **Last updated:** [April 16, 2024, 6:00pm UTC](https://allpix-squared-forum.web.cern.ch/t/installation-error/542 "2024-04-16T18:00:29Z")
While trying to install on WSL ubuntu I get the following error message after running make. Any advice on how to fix it? \[ 85%\] Building CXX object src/modules/DepositionGeant4/CMakeFiles/AllpixModuleDepositionGeant4.di… --- ## [Errors in first run example.conf](https://allpix-squared-forum.web.cern.ch/t/errors-in-first-run-example-conf/529)
**Author:** [@longli](https://allpix-squared-forum.web.cern.ch/u/longli)\ **Replies:** 3\ **Last updated:** [March 5, 2024, 12:43pm UTC](https://allpix-squared-forum.web.cern.ch/t/errors-in-first-run-example-conf/529 "2024-03-05T12:43:55Z")
Hello, I have installed allpix2 successfully on my unbutu22.04, with gcc 11.4.0 and cmake 3.22.1. Errors below occured when fisrtly run of example.conf: long@longli:~/workarea/allpix-squared/examples$ /usr/local/share… --- ## [Error/Warnings while reading histograms](https://allpix-squared-forum.web.cern.ch/t/error-warnings-while-reading-histograms/524)
**Author:** [@sakzai](https://allpix-squared-forum.web.cern.ch/u/sakzai)\ **Replies:** 6\ **Last updated:** [February 29, 2024, 8:47am UTC](https://allpix-squared-forum.web.cern.ch/t/error-warnings-while-reading-histograms/524 "2024-02-29T08:47:52Z")
I am trying to read histograms induced charge map in TRansientPropagation from a .root file. It gives me the following error root \[1\] (TFile \*) 0x5bdf130 Error in TBufferFile::CheckByteCount: object of class TH2D read … --- ## [Installation issue on MacOS sonoma 14](https://allpix-squared-forum.web.cern.ch/t/installation-issue-on-macos-sonoma-14/522)
**Author:** [@longli](https://allpix-squared-forum.web.cern.ch/u/longli)\ **Replies:** 8\ **Last updated:** [February 26, 2024, 1:37pm UTC](https://allpix-squared-forum.web.cern.ch/t/installation-issue-on-macos-sonoma-14/522 "2024-02-26T13:37:55Z")
I am try to install Allpix2 on my Mac with MacOS sonoma 14. GCC: Apple clang version 15.0.0 (clang-1500.1.0.2.5) Target: x86\_64-apple-darwin23.3.0 CMAKE: 3.24.4 I fialed in the make stage. Is sonoma 14 supported? --- ## [Errors during mesh\_converter run](https://allpix-squared-forum.web.cern.ch/t/errors-during-mesh-converter-run/518)
**Author:** [@danush](https://allpix-squared-forum.web.cern.ch/u/danush)\ **Replies:** 6\ **Last updated:** [February 20, 2024, 3:27pm UTC](https://allpix-squared-forum.web.cern.ch/t/errors-during-mesh-converter-run/518 "2024-02-20T15:27:20Z")
I am trying to extract electric field values from tcad files to .init files through allpix squared. I run using “./mesh\_converter -f pixel\_100V -c pixel\_100V.conf”. I am using the following .conf file: model="init" regi… [Next page](https://allpix-squared-forum.web.cern.ch/c/issues/5.md?page=1)