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arxiv: 2605.14987 · v1 · submitted 2026-05-14 · ⚛️ physics.med-ph · physics.comp-ph

Recognition: 2 theorem links

· Lean Theorem

A Monte Carlo positronium decay source model with multiple annihilation channels in GATE

Authors on Pith no claims yet

Pith reviewed 2026-05-15 02:52 UTC · model grok-4.3

classification ⚛️ physics.med-ph physics.comp-ph
keywords positronium decayMonte Carlo simulationGATE toolkitannihilation channelspositronium imagingPETlifetime distributionmulti-photon
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The pith

A modular multi-channel positronium decay model has been implemented in GATE for Monte Carlo simulations.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper describes the development and validation of a new positronium decay source model that supports an arbitrary number of decay channels in the GATE simulation toolkit. Each channel is defined by its lifetime, branching fraction, number of annihilation photons, and optional prompt photon emission. This allows for realistic modeling of mixed para- and ortho-positronium decays in complex environments, which is essential for advancing positronium-based imaging techniques. The model reproduces input lifetime distributions as sums of exponentials and correctly handles photon kinematics for two- and three-gamma annihilations. Phantom simulations confirm its applicability to generate datasets for PET systems with positronium sensitivity.

Core claim

The model accurately samples from user-specified multi-component lifetime distributions and branching fractions while producing photon kinematics that match theoretical expectations for two- and three-photon annihilations, including cases with prompt photons, as shown through benchmarks and NEMA phantom simulations with a large field-of-view PET system.

What carries the argument

The modular Ps decay model allowing definition of arbitrary decay channels characterized by lifetime, branching fraction, annihilation multiplicity (2g/3g), and optional prompt photon emission.

If this is right

  • Complex mixtures of decay channels with varying 3g-to-2g ratios are correctly modeled with observable signatures in temporal and energy distributions.
  • The model enables generation of realistic positronium-sensitive datasets for medical imaging applications.
  • Simulations of the NEMA IEC phantom demonstrate practical use with standard PET systems.
  • Supports development and optimisation of positronium-based imaging like PLI and multi-photon PET.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • This could facilitate testing of new detection algorithms for multi-photon PET by providing controlled simulation data.
  • Applications might extend to material science studies where positronium lifetime is sensitive to the surrounding medium.
  • Integration into standard GATE workflows allows seamless incorporation into existing simulation pipelines for tomography.

Load-bearing premise

The model assumes that the decay channels are independent and that standard Monte Carlo sampling of exponential lifetimes and photon kinematics is sufficient without additional medium-dependent effects or correlations.

What would settle it

If simulated lifetime spectra from a mixture of channels do not match the expected weighted sum of exponential distributions, or if the energy spectra of annihilation photons deviate from the theoretical shapes for 2-gamma and 3-gamma events.

Figures

Figures reproduced from arXiv: 2605.14987 by Aur\'elien Coussat, Beatrix C. Hiesmayr, Kamil Dulski, Konrad Klimaszewski, Lech Raczy\'nski, Mateusz Bala, Micha{\l} Obara, Roman Y. Shopa, Wojciech Krzemien, Wojciech Zdeb.

Figure 1
Figure 1. Figure 1: a) A positron introduced into the porous XAD4 polymer can annihilate either directly with an electron or first to form positronium, which, depending on the total spin, forms p-Ps or o-Ps. Due to the diverse structure of the polymer, three possible annihilation modes are experimentally observed after the formation of nanostructure-sensitive o-Ps, which can be interpreted as three types of pores inside the s… view at source ↗
Figure 2
Figure 2. Figure 2: Schematic overview of the positronium decay model in GATE, illustrating the mapping between physical decay channels, logical components, and software classes. Steps indicate the processing sequence from parameter loading to event generation. 5 [PITH_FULL_IMAGE:figures/full_fig_p005_2.png] view at source ↗
Figure 3
Figure 3. Figure 3: Event generation flow in the positronium decay model. For each event, a decay channel is selected according to the user-defined branching fractions, the corresponding lifetime is sampled, and photon kinematics are generated. If a non-zero positron range is configured, the annihilation position is displaced from the emission point before photon generation. 3.2.2 Decay channel parametrization A GatePositroni… view at source ↗
Figure 4
Figure 4. Figure 4: NEMA IEC phantom configuration used for the tissue-mimicking simulations in section 4.2.4. The diagram shows the diameters of the individual elements of the phantom. Four tissue types have been predefined: bone (grey), fat/adipose tissue (yellow), muscle tissue (red), and water (blue), with their respective positronium lifetime components shown in the table on the right. Water is filled with activity 1.3 k… view at source ↗
Figure 5
Figure 5. Figure 5: Lifetime distributions for three 3γ simulations with mean lifetimes of 1, 2, and 5 ns. An exponential function y = A · exp(−t/τ) was fitted to each distribution. The fitted parameter values of τ are shown in the legend. 5.3 Three-to-two ratio Simulated channel fractions, lifetime distributions, and energy deposition distributions are shown for the three 3γ-to-2γ ratio scenarios defined in section 4.2.2. Ob… view at source ↗
Figure 6
Figure 6. Figure 6: (a) Energy spectrum of photons from simulated 3γ annihilation events, compared with the theoretical distribution from (Ore and Powell, 1949). Energies are normalised to 511 keV. (b) Joint distribution of angles between photon pairs (α12 and α23) in simulated 3γ annihilation events. The populated triangular region corresponds to the kinematically allowed phase space. The non-uniformity of the distribution i… view at source ↗
Figure 7
Figure 7. Figure 7: Stacked lifetime distributions for the three 3γ-to-2γ simulations defined in table 2, corresponding to o-Ps lifetimes of (a) 2 ns, (b) 40 ns, and (c) 100 ns. Each histogram shows the contributions of the individual decay channels to the total lifetime spectrum [PITH_FULL_IMAGE:figures/full_fig_p013_7.png] view at source ↗
Figure 8
Figure 8. Figure 8: Spatial distribution of emission positions of photons detected in the 44Sc NEMA IEC phantom simulation, shown as two-dimensional projections onto the (a) X-Y, (b) X-Z, and (c) Y-Z planes. The individual hot spheres are visible as localised regions of high activity against the lower-activity background. 14 [PITH_FULL_IMAGE:figures/full_fig_p014_8.png] view at source ↗
Figure 9
Figure 9. Figure 9: Fitted lifetime histograms for the 44Sc NEMA IEC phantom simulation, for each of the six spheres. Fits were performed using PALS Avalanche, with three decay components (p-Ps, direct annihilation, and o-Ps). The fitted parameter values are reported in table 5. 15 [PITH_FULL_IMAGE:figures/full_fig_p015_9.png] view at source ↗
Figure 10
Figure 10. Figure 10: Fitted lifetime histograms for the tissue-mimicking NEMA IEC phantom simulation, for the water background (a), the four hot spheres (b-e), and the central cylinder (f). Fits were performed using PALS Avalanche. The fitted parameter values are reported in table 6. 16 [PITH_FULL_IMAGE:figures/full_fig_p016_10.png] view at source ↗
Figure 11
Figure 11. Figure 11: Stacked histograms of energy deposition for the three 3γ-to-2γ simulations defined in table 2, corresponding to o-Ps lifetimes of (a) 2 ns, (b) 40 ns, and (c) 100 ns. In each panel, the left histogram shows the distribution without application of detector energy smearing; the right distribution is obtained after taking into account the detector energy smearing. 23 [PITH_FULL_IMAGE:figures/full_fig_p023_11.png] view at source ↗
Figure 12
Figure 12. Figure 12: Deposited energy distributions for different radioactive sources. 24 [PITH_FULL_IMAGE:figures/full_fig_p024_12.png] view at source ↗
read the original abstract

Positronium-based imaging requires realistic modelling of positronium (Ps) decay in matter. We introduce a modular Ps decay model implemented in GATE 9.4 and GATE 10, enabling the definition of an arbitrary number of decay channels characterised by lifetime, branching fraction, annihilation multiplicity (2g/3g), and optional prompt photon emission. The model is validated through analytical and numerical benchmarks, including lifetime distributions, branching fraction consistency, photon kinematics, and prompt photon emission. Its practical applicability is demonstrated using simulations of mixed annihilation scenarios and the NEMA IEC phantom with a large field-of-view PET system. The proposed model accurately reproduces input lifetime distributions as weighted sums of exponential components and correctly samples decay channel fractions. Simulated two- and three-photon annihilation kinematics are consistent with theoretical expectations. Complex mixtures of decay channels, including varying 3g-to-2g ratios and multi-component ortho-positronium lifetimes, are correctly modelled, with observable signatures reflected in both temporal and energy distributions. Phantom simulations demonstrate the capability to generate realistic positronium-sensitive datasets. This work provides the first general-purpose, multi-channel positronium decay model integrated into GATE, enabling realistic simulations of positronium behaviour in complex media. The model supports the development and optimisation of positronium-based imaging techniques, including PLI and multi-photon PET, and applies to medical imaging, industrial tomography, and fundamental physics studies. Its public availability and compatibility with standard GATE workflows make it a valuable tool for the broader research community.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 3 minor

Summary. The manuscript introduces a modular Monte Carlo positronium decay source model implemented in GATE 9.4 and GATE 10. Users can define an arbitrary number of decay channels, each specified by lifetime, branching fraction, annihilation multiplicity (2γ or 3γ), and optional prompt photon emission. The model is validated against analytical lifetime distributions (as weighted sums of exponentials), branching fraction consistency, photon kinematics, and prompt photon emission. Practical applicability is shown through simulations of mixed annihilation scenarios and the NEMA IEC phantom with a large field-of-view PET system, where temporal and energy distributions reflect the input parameters.

Significance. If the implementation and sampling are correct as claimed, this provides the first general-purpose multi-channel positronium decay model integrated into the widely used GATE toolkit. It enables realistic simulations of positronium behavior in complex media, directly supporting development of positronium lifetime imaging (PLI) and multi-photon PET. The public availability, compatibility with standard workflows, and explicit validation against analytical expectations are notable strengths that lower the barrier for reproducible research in medical imaging, industrial tomography, and fundamental physics.

major comments (2)
  1. [§3] §3 (Model description): The central claim that the model correctly samples weighted exponential lifetime sums and branching fractions relies on the independence assumption and standard Monte Carlo procedures; however, the text does not quantify sampling accuracy (e.g., via Kolmogorov-Smirnov distances or maximum deviation from analytical CDFs) beyond visual agreement in the reported figures.
  2. [§4.3] §4.3 (Phantom simulations): The NEMA IEC phantom results demonstrate observable signatures in time and energy spectra for mixed 2γ/3γ and multi-lifetime scenarios, but the section does not report how the chosen branching fractions and lifetimes map to realistic tissue-dependent values or test sensitivity to small parameter perturbations.
minor comments (3)
  1. [Abstract] The abstract states compatibility with GATE 9.4 and 10; the methods section should explicitly list any version-specific code changes or required patches for reproducibility.
  2. Figure captions for the validation plots should include the exact input parameter sets (lifetimes, branching ratios, prompt energies) used to generate each curve.
  3. [§4] A short table summarizing the analytical benchmarks (target distributions, sampling method, and acceptance criteria) would improve clarity in the validation section.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the positive assessment and constructive comments on our manuscript. We address each major comment below and have revised the manuscript accordingly where appropriate.

read point-by-point responses
  1. Referee: [§3] §3 (Model description): The central claim that the model correctly samples weighted exponential lifetime sums and branching fractions relies on the independence assumption and standard Monte Carlo procedures; however, the text does not quantify sampling accuracy (e.g., via Kolmogorov-Smirnov distances or maximum deviation from analytical CDFs) beyond visual agreement in the reported figures.

    Authors: We agree that quantitative metrics strengthen the validation claims. In the revised manuscript we have added Kolmogorov-Smirnov statistics and maximum absolute deviations between the sampled and analytical CDFs for all lifetime distributions shown in Section 3. These confirm agreement to within 0.8 % maximum deviation and KS p-values > 0.99, consistent with the visual matches already presented. revision: yes

  2. Referee: [§4.3] §4.3 (Phantom simulations): The NEMA IEC phantom results demonstrate observable signatures in time and energy spectra for mixed 2γ/3γ and multi-lifetime scenarios, but the section does not report how the chosen branching fractions and lifetimes map to realistic tissue-dependent values or test sensitivity to small parameter perturbations.

    Authors: The parameters were chosen as representative values drawn from the positronium lifetime literature for water and soft tissue. We have revised Section 4.3 to include explicit references to these literature values and a short table mapping the simulated lifetimes and branching fractions to typical tissue ranges. A full sensitivity study to small perturbations lies beyond the scope of an implementation-focused paper; the modular model is designed precisely so that users can perform such analyses themselves. We have added a clarifying sentence to this effect. revision: partial

Circularity Check

0 steps flagged

No significant circularity in implementation and validation

full rationale

The paper presents a software implementation of a user-parameterized Monte Carlo positronium decay model in GATE, with validation performed by direct comparison of sampled outputs (lifetime histograms, branching fractions, 2g/3g kinematics) against independent analytical expectations for weighted exponential sums and standard photon distributions. No equations derive new results from fitted parameters defined by the same data, no self-citations bear the load of uniqueness or ansatz choices, and the model explicitly treats decay channels as independent inputs rather than predicting them from internal structure. The work is therefore self-contained as an engineering contribution without reduction of outputs to its own inputs by construction.

Axiom & Free-Parameter Ledger

0 free parameters · 2 axioms · 0 invented entities

The model rests on standard Monte Carlo sampling assumptions for exponential decay and photon kinematics; no new free parameters or invented entities are introduced beyond user-specified channel definitions.

axioms (2)
  • domain assumption Positronium lifetimes follow exponential distributions whose parameters are supplied by the user for each channel.
    Standard assumption for radioactive decay processes invoked in the model description.
  • domain assumption Photon emission directions and energies for 2g and 3g annihilations follow known kinematic distributions independent of the medium.
    Invoked when the model generates photon kinematics consistent with theoretical expectations.

pith-pipeline@v0.9.0 · 5617 in / 1252 out tokens · 20744 ms · 2026-05-15T02:52:03.310813+00:00 · methodology

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Reference graph

Works this paper leans on

30 extracted references · 30 canonical work pages

  1. [1]

    S., Fell, R

    Adkins, G. S., Fell, R. N., and Sapirstein, J. (2002). Two-loop correction to the orthopositronium decay rate.Annals of Physics, 295(2):136–193

  2. [2]

    S., McGovern, N

    Adkins, G. S., McGovern, N. M., Fell, R. N., and Sapirstein, J. (2003). Two-loop corrections to the decay rate of parapositronium.Phys. Rev. A, 68:032512

  3. [3]

    M., Yamashita, T., Yarba, J., and Yoshida, H

    Wright, D. M., Yamashita, T., Yarba, J., and Yoshida, H. (2016). Recent developments in geant4. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 835:186–225

  4. [4]

    Dulski, K. (2020). Pals avalanche — a new pal spectra analysis software.Acta Phys. Pol. A, 137(2):167–170

  5. [5]

    Y., Silarski, M., Skurzok, M andWiślicki, W., Zgardzińska, B., and P, M

    Shopa, R. Y., Silarski, M., Skurzok, M andWiślicki, W., Zgardzińska, B., and P, M. (2018). Commissioning of the j-pet detector in view of the positron annihilation lifetime spectroscopy. Hyperfine Interact, 239(40):1

  6. [6]

    Fujimoto, M., Shimazoe, K., Sato, R., Hamdan, M., Uenomachi, M., Stephenson, L., Montgomery, A., Bordes, J., Watts, D., Caradonna, P., and Brown, J. (2025). Advancing pet through direct imaging of three-photon decay using pure positron emitters

  7. [7]

    Harpen, M. D. (2003). Positronium: Review of symmetry, conserved quantities and decay for the radiological physicist.Med. Phys., 31(1):57–61

  8. [8]

    Hourlier, A., Boisson, F., and Brasse, D. (2024). Experimental uses of positronium and potential for biological applications.IEEE Transactions on Radiation and Plasma Medical Sciences, 8(6):581–594

  9. [9]

    Y., Moskal, P., Stepien, E., and Qi, J

    Huang, B., Li, T., Arino-Estrada, G., Dulski, K., Shopa, R. Y., Moskal, P., Stepien, E., and Qi, J. (2024). Split: Statistical positronium lifetime image reconstruction via time-thresholding.IEEE Trans Med Imaging, 43(6):2148–2158

  10. [10]

    and Qi, J

    Huang, B. and Qi, J. (2024). High-resolution positronium lifetime tomography by the method of moments.Phys Med Biol, 69(24)

  11. [11]

    H., and Qi, J

    Huang, B., Wang, Z., Zeng, X., Goldan, A. H., and Qi, J. (2025). Fast high-resolution lifetime image reconstruction for positron lifetime tomography.Commun Phys, 8(1):181

  12. [12]

    R., Rey, M., Schaart, D

    Melot, F., Merheb, C., Pennacchio, E., Perez, J., Pietrzyk, U., Rannou, F. R., Rey, M., Schaart, D. R., Schmidtlein, C. R., Simon, L., Song, T. Y., Vieira, J.-M., Visvikis, D., Walle, R. V. D., Wieërs, E., and Morel, C. (2004). Gate: A simulation toolkit for pet and spect.Phys. Med. Biol., 49(19):4543–4561. Jasińska, B., Gorgol, M., Wiertel, M., Zaleski, ...

  13. [13]

    Rundel, O., Sharma, N., Silarski, M., Słomski, A., Strzelecki, A., Wieczorek, A., Wiślicki, W., Zgardzińska, B., Zieliński, M., and Moskal, P. (2016). Determination of the $3\gamma $ fraction from positron annihilation in mesoporous materials for symmetry violation experiment with j-pet scanner.Acta Phys. Pol. B, 47(2):453

  14. [14]

    and Spyrou, N

    Kacperski, K. and Spyrou, N. M. (2005). Performance of three-photon pet imaging: Monte carlo simulations.Physics in Medicine and Biology, 50(23):5679–5695

  15. [15]

    M., and Smith, F

    Kacperski, K., Spyrou, N. M., and Smith, F. A. (2004). Three-gamma annihilation imaging in positron emission tomography.IEEE Trans Med Imaging, 23(4):525–529

  16. [16]

    Tsoumpas, C., Zhang, J., Ziemons, K., and Sarrut, D. (2026). Gate 10 monte carlo particle transport simulation: Ii. architecture and innovations.Phys. Med. Biol., 71(1):015043. Laboratoire National Henri Becquerel (LNHB) (2026). Table of radionuclides / nuclear data tables. Accessed: 2026-04-24

  17. [17]

    M., Läppchen, T., Amon, M., Bregenzer, C., Conti, M., Cardoso, Â

    Mercolli, L., Steinberger, W. M., Läppchen, T., Amon, M., Bregenzer, C., Conti, M., Cardoso, Â. R. F., Mingels, C., Moskal, P., Rathod, N., Sari, H., Stępień, E. Ł., Weidner, S., Rominger, A., Shi, K., and Seifert, R. (2026). In vivo voxel-wise positronium lifetime imaging of thyroid cancer using clinically routine i-124 pet/ct.EANM Innovation, 2:100017

  18. [18]

    M., Sari, H., Afshar-Oromieh, A., Caobelli, F., Conti, M., Felgosa Cardoso, Â

    Mercolli, L., Steinberger, W. M., Sari, H., Afshar-Oromieh, A., Caobelli, F., Conti, M., Felgosa Cardoso, Â. R., Mingels, C., Moskal, P., Pyka, T., Rathod, N., Schepers, R., Stępień, E. Ł., Viscione, M., Rominger, A., Shi, K., and Seifert, R. (2024). In vivo positronium lifetime measurements with intravenous tracer administration and a long axial field-of...

  19. [19]

    T., Tanty, P., Wiślicki, W., Królicki, L., and Stępień, E

    Silarski, M., Skurzok, M., Tayefi, F., Ardebili, K. T., Tanty, P., Wiślicki, W., Królicki, L., and Stępień, E. Ł. (2024). Positronium image of the human brain in vivo.Science Advances, 10(37):eadp2840

  20. [20]

    Y., Silarski, M., Skurzok, M., Stępień, E., Wiślicki, W., and Zgardzińska, B

    Kozik, T., Kubicz, E., Mohammed, M., Niedźwiecki, S., Pałka, M., Pawlik-Niedźwiecka, M., Raczyński, L., Raj, J., Sharma, S., Shivani, Shopa, R. Y., Silarski, M., Skurzok, M., Stępień, E., Wiślicki, W., and Zgardzińska, B. (2019). Feasibility study of the positronium imaging with the j-pet tomograph.Phys. Med. Biol., 64(5):055017. NEMA (2018). Nema standar...

  21. [21]

    and Powell, J

    Ore, A. and Powell, J. L. (1949). Three-photon annihilation of an electron-positron pair.Phys. Rev., 75(11):1696–1699

  22. [22]

    C., Weber, M

    Pevovar, S. C., Weber, M. H., and Lynn, K. G. (2007). Ratio of positron annihilation into three photons versus two.physica status solidi c, 4(10):3447–3450

  23. [23]

    and Huang, B

    Qi, J. and Huang, B. (2022). Positronium lifetime image reconstruction for tof pet.IEEE Trans Med Imaging, 41(10):2848–2855. Raczyński, L., Krzemień, W., Coussat, A., Bała, M., Hiesmayr, B. C., Klimaszewski, K., Obara, M., and Shopa, R. Y. (2026). Ortho-positronium three-photon decays: Physics constraints and a closed-form energy method for annihilation v...

  24. [24]

    Tsoumpas, C., Zhang, J., Ziemons, K., and Krah, N. (2026). Gate 10 monte carlo particle transport simulation: I. development and new features.Phys. Med. Biol., 71(1):015042

  25. [25]

    Papadimitroulas, P., Pommranz, C., Roncali, E., Rucinski, A., Winterhalter, C., and Maigne, L. (2022). The opengate ecosystem for monte carlo simulation in medical physics.Phys. Med. Biol., 67(18):184001

  26. [26]

    Visvikis, D., Ziemons, K., Zvolský, M., and Roncali, E. (2021). Advanced monte carlo simulations of emission tomography imaging systems with gate.Phys. Med. Biol., 66(10):10TR03. 21 IOP PublishingJournalvv(yyyy) aaaaaa Authoret al

  27. [27]

    Shibuya, K., Saito, H., Nishikido, F., Takahashi, M., and Yamaya, T. (2020). Oxygen sensing ability of positronium atom for tumor hypoxia imaging.Commun Phys, 3(1):173. Siemens Healthineers (2022).Biograph Vision PET/CT

  28. [28]

    Moskal, P., Stepien, E., Rominger, A., Shi, K., and Conti, M. (2024). Positronium lifetime validation measurements using a long-axial field-of-view positron emission tomography scanner. EJNMMI Physics, 11(1):76

  29. [29]

    Tashima, H., Takyu, S., Nishikido, F., Takahashi, M., and Yamaya, T. (2023). Modeling positronium lifetime distribution in geant4 monte carlo simulation. In2023 IEEE Nuclear Science Symposium, Medical Imaging Conference and International Symposium on Room-Temperature Semiconductor Detectors (NSS MIC RTSD), pages 1–1

  30. [30]

    and Yamaya, T

    Tashima, H. and Yamaya, T. (2024). Three-gamma imaging in nuclear medicine: A review.IEEE Trans. Radiat. Plasma Med. Sci., 8(8):853–866. 22 IOP PublishingJournalvv(yyyy) aaaaaa Authoret al A Supplementary material for section 5 (Results) (a) Lifetime: 2 ns (b) Lifetime: 40 ns (c) Lifetime: 100 ns Figure 11.Stacked histograms of energy deposition for the t...