CMS logoCMS event Hgg
Compact Muon Solenoid
LHC, CERN

CMS-PFT-25-001 ; CERN-EP-2025-300
Full event interpretation with machine-learning-based particle-flow reconstruction in the CMS detector
Submitted to Eur. Phys. J. C
Abstract: The particle-flow (PF) algorithm constructs a global description of each particle collision by producing a comprehensive list of final-state particles, and is central to event reconstruction in the CMS experiment at the CERN LHC. The existing PF implementation relies on physics-motivated heuristics and assumptions that can be replaced by machine-learning (ML) models trained directly on simulated data and naturally suited to modern graphics processing units (GPUs). A state-of-the-art ML-based PF (MLPF) reconstruction algorithm, implemented within the CMS software framework, is presented. The MLPF algorithm performs a learnable full-event reconstruction on GPUs, generalizes across detector conditions and collision energies, and replaces multiple modular reconstruction steps with a single unified model. Physics performance comparable to standard PF reconstruction is achieved in both simulation and data, with improved jet energy resolution and inference time. In simulated top quark-antiquark events under LHC Run-3 (2023-2024) conditions, the jet energy resolution improves by 10-20% for jets with transverse momentum between 30-100 GeV. Inference time is evaluated using simulated multijet events, with a median of 20 ms per event on an Nvidia L4 GPU, compared to approximately 110 ms for the standard CMS PF reconstruction.
Figures & Tables Summary References CMS Publications
Figures

png pdf
Figure 1:
Validation of the MLPF particle-level target, after removing the contributions from the pileup particles, using $ \mathrm{t} \overline{\mathrm{t}} $ simulation with pileup. The $ p_{\mathrm{T}} $ distribution of target particles and truth particles derived from PYTHIA stable particles (upper left). The $ p_{\mathrm{T}} $ distribution of jets clustered from each particle set (upper right). The jet response relative to particle-level jets (lower left). The target $ p_{\mathrm{T}}^\text{miss} $ as a function of the PYTHIA truth $ p_{\mathrm{T}}^\text{miss} $ (lower right). The target particle set, after removing the contribution from pileup, generally aligns well with the pileup-free PYTHIA truth.

png pdf
Figure 1-a:
Validation of the MLPF particle-level target, after removing the contributions from the pileup particles, using $ \mathrm{t} \overline{\mathrm{t}} $ simulation with pileup. The $ p_{\mathrm{T}} $ distribution of target particles and truth particles derived from PYTHIA stable particles (upper left). The $ p_{\mathrm{T}} $ distribution of jets clustered from each particle set (upper right). The jet response relative to particle-level jets (lower left). The target $ p_{\mathrm{T}}^\text{miss} $ as a function of the PYTHIA truth $ p_{\mathrm{T}}^\text{miss} $ (lower right). The target particle set, after removing the contribution from pileup, generally aligns well with the pileup-free PYTHIA truth.

png pdf
Figure 1-b:
Validation of the MLPF particle-level target, after removing the contributions from the pileup particles, using $ \mathrm{t} \overline{\mathrm{t}} $ simulation with pileup. The $ p_{\mathrm{T}} $ distribution of target particles and truth particles derived from PYTHIA stable particles (upper left). The $ p_{\mathrm{T}} $ distribution of jets clustered from each particle set (upper right). The jet response relative to particle-level jets (lower left). The target $ p_{\mathrm{T}}^\text{miss} $ as a function of the PYTHIA truth $ p_{\mathrm{T}}^\text{miss} $ (lower right). The target particle set, after removing the contribution from pileup, generally aligns well with the pileup-free PYTHIA truth.

png pdf
Figure 1-c:
Validation of the MLPF particle-level target, after removing the contributions from the pileup particles, using $ \mathrm{t} \overline{\mathrm{t}} $ simulation with pileup. The $ p_{\mathrm{T}} $ distribution of target particles and truth particles derived from PYTHIA stable particles (upper left). The $ p_{\mathrm{T}} $ distribution of jets clustered from each particle set (upper right). The jet response relative to particle-level jets (lower left). The target $ p_{\mathrm{T}}^\text{miss} $ as a function of the PYTHIA truth $ p_{\mathrm{T}}^\text{miss} $ (lower right). The target particle set, after removing the contribution from pileup, generally aligns well with the pileup-free PYTHIA truth.

png pdf
Figure 1-d:
Validation of the MLPF particle-level target, after removing the contributions from the pileup particles, using $ \mathrm{t} \overline{\mathrm{t}} $ simulation with pileup. The $ p_{\mathrm{T}} $ distribution of target particles and truth particles derived from PYTHIA stable particles (upper left). The $ p_{\mathrm{T}} $ distribution of jets clustered from each particle set (upper right). The jet response relative to particle-level jets (lower left). The target $ p_{\mathrm{T}}^\text{miss} $ as a function of the PYTHIA truth $ p_{\mathrm{T}}^\text{miss} $ (lower right). The target particle set, after removing the contribution from pileup, generally aligns well with the pileup-free PYTHIA truth.

png pdf
Figure 2:
The neural network structure of the model. Input and output features are visualized in purple. Pointwise FFNs are visualized in green, and layers with full-event correlations in red. The last dimension contains a binary output to predict the presence of a particle (Valid), multi-class outputs for the PID, and the predicted momentum values.

png pdf
Figure 2-a:
The neural network structure of the model. Input and output features are visualized in purple. Pointwise FFNs are visualized in green, and layers with full-event correlations in red. The last dimension contains a binary output to predict the presence of a particle (Valid), multi-class outputs for the PID, and the predicted momentum values.

png pdf
Figure 2-b:
The neural network structure of the model. Input and output features are visualized in purple. Pointwise FFNs are visualized in green, and layers with full-event correlations in red. The last dimension contains a binary output to predict the presence of a particle (Valid), multi-class outputs for the PID, and the predicted momentum values.

png pdf
Figure 3:
The PID, binary classification, and regression losses for the training and validation data sets, as a function of the training epoch. We observe both the training and validation losses to be smoothly converging. The training loss is evaluated with a partially-trained model throughout the training epoch on the training events (80%), while the validation loss is computed with the model weights at the end of the epoch on the validation events (20%). The losses are measured in arbitrary units, averaged across the events.

png pdf
Figure 3-a:
The PID, binary classification, and regression losses for the training and validation data sets, as a function of the training epoch. We observe both the training and validation losses to be smoothly converging. The training loss is evaluated with a partially-trained model throughout the training epoch on the training events (80%), while the validation loss is computed with the model weights at the end of the epoch on the validation events (20%). The losses are measured in arbitrary units, averaged across the events.

png pdf
Figure 3-b:
The PID, binary classification, and regression losses for the training and validation data sets, as a function of the training epoch. We observe both the training and validation losses to be smoothly converging. The training loss is evaluated with a partially-trained model throughout the training epoch on the training events (80%), while the validation loss is computed with the model weights at the end of the epoch on the validation events (20%). The losses are measured in arbitrary units, averaged across the events.

png pdf
Figure 3-c:
The PID, binary classification, and regression losses for the training and validation data sets, as a function of the training epoch. We observe both the training and validation losses to be smoothly converging. The training loss is evaluated with a partially-trained model throughout the training epoch on the training events (80%), while the validation loss is computed with the model weights at the end of the epoch on the validation events (20%). The losses are measured in arbitrary units, averaged across the events.

png pdf
Figure 4:
The particle $ p_{\mathrm{T}} $ (left) and $ \eta $ (right) distributions split by PID for MC particles (Gen), and PF and MLPF candidates in $ \mathrm{t} \overline{\mathrm{t}} $ events. In the forward region, the PF and MLPF algorithms do not attempt to identify particles, but instead reconstruct the deposits as either electromagnetic or hadronic.

png pdf
Figure 4-a:
The particle $ p_{\mathrm{T}} $ (left) and $ \eta $ (right) distributions split by PID for MC particles (Gen), and PF and MLPF candidates in $ \mathrm{t} \overline{\mathrm{t}} $ events. In the forward region, the PF and MLPF algorithms do not attempt to identify particles, but instead reconstruct the deposits as either electromagnetic or hadronic.

png pdf
Figure 4-b:
The particle $ p_{\mathrm{T}} $ (left) and $ \eta $ (right) distributions split by PID for MC particles (Gen), and PF and MLPF candidates in $ \mathrm{t} \overline{\mathrm{t}} $ events. In the forward region, the PF and MLPF algorithms do not attempt to identify particles, but instead reconstruct the deposits as either electromagnetic or hadronic.

png pdf
Figure 5:
Neutral hadron efficiency (left) and misidentification rate (right) as functions of $ p_{\mathrm{T}} $ for PF (blue) and MLPF (red) in $ \mathrm{t} \overline{\mathrm{t}} $ events based on $ \Delta R $ matching to generator-level particles. The MLPF algorithm generally has higher efficiency at a lower misidentification rate. The vertical bars indicate the statistical uncertainties on the respective distributions.

png pdf
Figure 5-a:
Neutral hadron efficiency (left) and misidentification rate (right) as functions of $ p_{\mathrm{T}} $ for PF (blue) and MLPF (red) in $ \mathrm{t} \overline{\mathrm{t}} $ events based on $ \Delta R $ matching to generator-level particles. The MLPF algorithm generally has higher efficiency at a lower misidentification rate. The vertical bars indicate the statistical uncertainties on the respective distributions.

png pdf
Figure 5-b:
Neutral hadron efficiency (left) and misidentification rate (right) as functions of $ p_{\mathrm{T}} $ for PF (blue) and MLPF (red) in $ \mathrm{t} \overline{\mathrm{t}} $ events based on $ \Delta R $ matching to generator-level particles. The MLPF algorithm generally has higher efficiency at a lower misidentification rate. The vertical bars indicate the statistical uncertainties on the respective distributions.

png pdf
Figure 6:
The corrected jet $ p_{\mathrm{T}} $ distribution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions. MLPF is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. We show the jet $ p_{\mathrm{T}} $ distribution after simulated response calibration. The shaded bands indicate the statistical uncertainties on Gen.

png pdf
Figure 6-a:
The corrected jet $ p_{\mathrm{T}} $ distribution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions. MLPF is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. We show the jet $ p_{\mathrm{T}} $ distribution after simulated response calibration. The shaded bands indicate the statistical uncertainties on Gen.

png pdf
Figure 6-b:
The corrected jet $ p_{\mathrm{T}} $ distribution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions. MLPF is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. We show the jet $ p_{\mathrm{T}} $ distribution after simulated response calibration. The shaded bands indicate the statistical uncertainties on Gen.

png pdf
Figure 6-c:
The corrected jet $ p_{\mathrm{T}} $ distribution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions. MLPF is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. We show the jet $ p_{\mathrm{T}} $ distribution after simulated response calibration. The shaded bands indicate the statistical uncertainties on Gen.

png pdf
Figure 6-d:
The corrected jet $ p_{\mathrm{T}} $ distribution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions. MLPF is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. We show the jet $ p_{\mathrm{T}} $ distribution after simulated response calibration. The shaded bands indicate the statistical uncertainties on Gen.

png pdf
Figure 7:
The jet resolution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions, after simulated response calibration. The MLPF algorithm is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. The jet resolution is parameterized by fitting a Gaussian distribution and dividing the best-fit standard deviation by the mean, showing the bin midpoints on the horizontal axis.

png pdf
Figure 7-a:
The jet resolution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions, after simulated response calibration. The MLPF algorithm is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. The jet resolution is parameterized by fitting a Gaussian distribution and dividing the best-fit standard deviation by the mean, showing the bin midpoints on the horizontal axis.

png pdf
Figure 7-b:
The jet resolution in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) validation samples with 55--75 pileup interactions, after simulated response calibration. The MLPF algorithm is only trained to reconstruct particles, and is never explicitly optimized to reconstruct jets. The PUPPI algorithm is applied to both PF and MLPF jets to perform pileup subtraction. The jet resolution is parameterized by fitting a Gaussian distribution and dividing the best-fit standard deviation by the mean, showing the bin midpoints on the horizontal axis.

png pdf
Figure 8:
Uncalibrated $ p_{\mathrm{T}}^\text{miss} $ in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) samples with pileup from offline reconstruction using PF and MLPF. The MLPF algorithm is only trained to reconstruct particles, and is never explicitly optimized to reconstruct $ p_{\mathrm{T}}^\text{miss} $. The $ p_{\mathrm{T}}^\text{miss} $ distributions from PF and MLPF are found to be generally consistent, with MLPF reconstructing a somewhat harder $ p_{\mathrm{T}}^\text{miss} $ spectrum in the tails. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 8-a:
Uncalibrated $ p_{\mathrm{T}}^\text{miss} $ in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) samples with pileup from offline reconstruction using PF and MLPF. The MLPF algorithm is only trained to reconstruct particles, and is never explicitly optimized to reconstruct $ p_{\mathrm{T}}^\text{miss} $. The $ p_{\mathrm{T}}^\text{miss} $ distributions from PF and MLPF are found to be generally consistent, with MLPF reconstructing a somewhat harder $ p_{\mathrm{T}}^\text{miss} $ spectrum in the tails. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 8-b:
Uncalibrated $ p_{\mathrm{T}}^\text{miss} $ in $ \mathrm{t} \overline{\mathrm{t}} $ (left) and QCD multijet (right) samples with pileup from offline reconstruction using PF and MLPF. The MLPF algorithm is only trained to reconstruct particles, and is never explicitly optimized to reconstruct $ p_{\mathrm{T}}^\text{miss} $. The $ p_{\mathrm{T}}^\text{miss} $ distributions from PF and MLPF are found to be generally consistent, with MLPF reconstructing a somewhat harder $ p_{\mathrm{T}}^\text{miss} $ spectrum in the tails. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 9:
Distributions of the leading jet $ p_{\text{T,corr}} $ (left), the dijet asymmetry (center), and $ p_{\mathrm{T}}^\text{miss} $ (right) in a small sample of dijet data collected in Run 3. The distributions are largely compatible. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 9-a:
Distributions of the leading jet $ p_{\text{T,corr}} $ (left), the dijet asymmetry (center), and $ p_{\mathrm{T}}^\text{miss} $ (right) in a small sample of dijet data collected in Run 3. The distributions are largely compatible. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 9-b:
Distributions of the leading jet $ p_{\text{T,corr}} $ (left), the dijet asymmetry (center), and $ p_{\mathrm{T}}^\text{miss} $ (right) in a small sample of dijet data collected in Run 3. The distributions are largely compatible. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 9-c:
Distributions of the leading jet $ p_{\text{T,corr}} $ (left), the dijet asymmetry (center), and $ p_{\mathrm{T}}^\text{miss} $ (right) in a small sample of dijet data collected in Run 3. The distributions are largely compatible. The vertical bars indicate the statistical uncertainties on the respective distributions, and the shaded bands in the ratio panel indicate the statistical uncertainties on PF.

png pdf
Figure 10:
The runtime of the baseline particle-flow reconstruction compared to the MLPF inference, directly within the CMS offline software using the native ONNXRUNTIME on GPU.

png pdf
Figure 10-a:
The runtime of the baseline particle-flow reconstruction compared to the MLPF inference, directly within the CMS offline software using the native ONNXRUNTIME on GPU.

png pdf
Figure 10-b:
The runtime of the baseline particle-flow reconstruction compared to the MLPF inference, directly within the CMS offline software using the native ONNXRUNTIME on GPU.

png pdf
Figure 10-c:
The runtime of the baseline particle-flow reconstruction compared to the MLPF inference, directly within the CMS offline software using the native ONNXRUNTIME on GPU.

png pdf
Figure 10-d:
The runtime of the baseline particle-flow reconstruction compared to the MLPF inference, directly within the CMS offline software using the native ONNXRUNTIME on GPU.
Tables

png pdf
Table 1:
Monte Carlo simulation samples used for optimizing, validating, and testing the model. The training and validation samples are divided using an 80%/20% split, respectively. The symbols $ \text{---} $ in the 3rd column represent samples generated without pileup.
Summary
A machine-learning (ML)-based algorithm for particle-flow (PF) reconstruction in the CMS experiment has been presented. The algorithm correlates tracks and calorimeter clusters using successive transformer layers, and outputs a list of reconstructed particles with four-momenta and particle identification values. The algorithm is functionally equivalent to the standard PF algorithm currently used in CMS. The model is trained on CMS Run-3 (2023--2024) full simulation data sets that include realistic pileup conditions, and its performance is evaluated in simulated top quark-antiquark ( $ \mathrm{t} \overline{\mathrm{t}} $) and quantum chromodynamics multijet testing samples across different experimental conditions, as well as on data collected using a dijet trigger. To ensure computational efficiency, the model avoids quadratic scaling in runtime and memory by efficiently employing modern graphics processing units (GPUs). The ML-based PF (MLPF) algorithm achieves physics performance comparable to the standard PF algorithm, while enabling GPU acceleration for full event reconstruction within the CMS offline software framework. Specifically, we observe improved neutral hadron efficiency with MLPF while maintaining the same misidentification rate as standard PF. For jets with $ p_{\mathrm{T}} $ between 30--100 GeV in $ \mathrm{t} \overline{\mathrm{t}} $ events, we observe a 10--20% improvement in jet energy resolution compared to standard PF. The algorithm delivers a per-event runtime of approximately 20\unitms on an Nvidia L4 inference GPU, with 64 inference streams running in parallel per GPU. We also observe improved runtime scaling with event size compared to the standard PF algorithm, highlighting the computational robustness of the approach. While the MLPF algorithm has been successfully benchmarked under Run-3 conditions, its primary motivation lies in deployment at the high-luminosity upgrade of the LHC (HL-LHC), where the increased event complexity and pileup conditions demand both high physics performance and computational scalability. To deploy MLPF in production at the HL-LHC, several developments are foreseen. First, the model must be retrained for the upgraded detector and higher pileup conditions. Second, ensuring the portability of the inference across different GPU generations and hardware vendors is essential. Third, the model inference can be further optimized through techniques such as sparse or block attention, quantization, pruning, and asynchronous or batched execution. Finally, the physics performance and robustness can be improved through additional training and extensive cross-checks on a wide variety of simulated and data samples.
References
1 CMS Collaboration Particle-flow reconstruction and global event description with the CMS detector JINST 12 (2017) P10003 CMS-PRF-14-001
1706.04965
2 ALEPH Collaboration Performance of the ALEPH detector at LEP NIM A 360 (1995) 481
3 ATLAS Collaboration Jet reconstruction and performance using particle flow with the ATLAS detector EPJC 77 (2017) 466 1703.10485
4 A. Bocci, S. Lami, S. Kuhlmann, and G. Latino Study of jet energy resolution at CDF Int. J. Mod. Phys. A 16 (2001) 255
5 CDF Collaboration A search for supersymmetric Higgs bosons in the di-tau decay mode in $ \mathrm{p}\overline{\mathrm{p}} $ collisions at 1.8 TeV PRD 72 (2005) 112008 hep-ex/0506042
6 CDF Collaboration Measurement of $ \sigma(\mathrm{p}\overline{\mathrm{p}} \to \mathrm{Z})\mathcal{B}(\mathrm{Z} \to \tau\tau) $ in $ \mathrm{p}\overline{\mathrm{p}} $ collisions at $ \sqrt{s}= $ 1.96 TeV PRD 75 (2007) 092004
7 CELLO Collaboration An analysis of the charged and neutral energy flow in $ \mathrm{e}^+\mathrm{e}^- $ hadronic annihilation at 34 GeV, and a determination of the QCD effective coupling constant PLB 113 (1982) 427
8 D0 Collaboration Measurement of $ \sigma(\mathrm{p}\overline{\mathrm{p}} \to \mathrm{Z} + \mathrm{X})\mathcal{B}(\mathrm{Z} \to \tau^+ \tau^-) $ at $ \sqrt{s} = $ 1.96 TeV PLB 670 (2009) 292 0808.1306
9 DELPHI Collaboration Performance of the DELPHI detector NIM A 378 (1996) 57
10 H1 Collaboration Measurement of charged particle multiplicity distributions in DIS at HERA and its implication to entanglement entropy of partons EPJC 81 (2021) 212 2011.01812
11 ZEUS Collaboration Measurement of the diffractive structure function $ F_2^{D(4)} $ at HERA EPJC 1 (1998) 81 hep-ex/9709021
12 ZEUS Collaboration Measurement of the diffractive cross-section in deep inelastic scattering using ZEUS 1994 data EPJC 6 (1999) 43 hep-ex/9807010
13 FCC Collaboration FCC-ee: The lepton collider. Future Circular Collider conceptual design report volume 2 Eur. Phys. J. ST 228 (2019) 261
14 CMSnoop The International Linear Collider technical design report - volume 1: executive summary \hrefT. Behnke et al.,, 2013 1306.6327
15 CEPC Study Group CEPC conceptual design report: volume 2 - physics \& detector 1811.10545
16 F. Mokhtar et al. Fine-tuning machine-learned particle-flow reconstruction for new detector geometries in future colliders PRD 111 (2025) 092015 2503.00131
17 F. A. Di Bello et al. Towards a computer vision particle flow EPJC 81 (2021) 107 2003.08863
18 J. Kieseler Object condensation: one-stage grid-free multi-object reconstruction in physics detectors, graph and image data EPJC 80 (2020) 886 2002.03605
19 J. Shlomi, P. Battaglia, and J.-R. Vlimant Graph neural networks in particle physics Mach. Learn. Sci. Tech. 2 (2021) 021001 2007.13681
20 J. Pata et al. MLPF: Efficient machine-learned particle-flow reconstruction using graph neural networks EPJC 81 (2021) 381 2101.08578
21 CMS Collaboration GNN-based end-to-end reconstruction in the CMS Phase 2 High-Granularity Calorimeter J. Phys. Conf. Ser. 2438 (2023) 012090 2203.01189
22 CMS Collaboration Machine learning for particle flow reconstruction at CMS J. Phys. Conf. Ser. 2438 (2023) 012100 2203.00330
23 F. Mokhtar et al. Progress towards an improved particle flow algorithm at CMS with machine learning in st Int. Workshop on Advanced Computing and Analysis Techniques in Physics Research, 2023
Proc. 2 (2023) 1
2303.17657
24 F. A. Di Bello et al. Reconstructing particles in jets using set transformer and hypergraph prediction networks EPJC 83 (2023) 596 2212.01328
25 J. Pata et al. Improved particle-flow event reconstruction with scalable neural networks for current and future particle detectors Commun. Phys. 7 (2024) 124 2309.06782
26 P. Wahlen and T. Suehara Particle-flow reconstruction with transformer Eur. Phys. J. Web Conf. 315 (2024) 03010
27 N. Kakati et al. HGPflow: Extending hypergraph particle flow to collider event reconstruction EPJC 85 (2025) 847 2410.23236
28 D. Kobylianskii et al. GLOW: A unified particle flow transformer in Proc. 8th th Conference on Neural Information Processing Systems, 2025
Machine Learning and the Physical Sciences Workshop at the 3 (2025) 9
2508.20092
29 CMS Collaboration Portable acceleration of CMS computing workflows with coprocessors as a service Comput. Softw. Big Sci. 8 (2024) 17 CMS-MLG-23-001
2402.15366
30 I. Bejar Alonso et al. High-Luminosity Large Hadron Collider (HL-LHC): technical design report CERN Yellow Rep. Monogr. 10 (2020)
31 T. Dorigo et al. Toward the end-to-end optimization of particle physics instruments with differentiable programming Rev. Phys. 10 (2023) 100085 2203.13818
32 M. Aehle et al. Progress in end-to-end optimization of fundamental physics experimental apparata with differentiable programming Rev. Phys. 13 (2025) 100120 2310.05673
33 CMS Collaboration High-precision measurement of the W boson mass with the CMS experiment at the LHC Accepted by \emphNature, 2024 CMS-SMP-23-002
2412.13872
34 H. Qu and L. Gouskos Jet tagging via particle clouds PRD 101 (2020) 056019 1902.08570
35 H. Qu, C. Li, and S. Qian Particle transformer for jet tagging in th Int. Conference on Machine Learning, volume 162, 2022
Proc. 3 (2022) 18281
2202.03772
36 E. A. Moreno et al. JEDI-net: a jet identification algorithm based on interaction networks EPJC 80 (2020) 58 1908.05318
37 E. A. Moreno et al. Interaction networks for the identification of boosted $ \mathrm{H} \to \mathrm{b}\overline{\mathrm{b}} $ decays PRD 102 (2020) 012010 1909.12285
38 V. Mikuni and F. Canelli ABCNet: An attention-based method for particle tagging Eur. Phys. J. Plus 135 (2020) 463 2001.05311
39 S. Farrell et al. Novel deep learning methods for track reconstruction in Proc. 4th Int. Workshop Connecting the Dots, 2018 1810.06111
40 X. Ju et al. Graph neural networks for particle reconstruction in high energy physics detectors in Proc. 2nd rd Conference on Neural Information Processing Systems, 2020
Machine Learning and the Physical Sciences Workshop at the 3 (2020) 3
2003.11603
41 S. Amrouche et al. The tracking machine learning challenge: Accuracy phase in The NeurIPS '18 Competition, 2020
link
1904.06778
42 S. Amrouche et al. Similarity hashing for charged particle tracking in, 2019
Proc. IEEE International Conference on Big Data 201 (2019) 1595
43 N. Choma et al. Track seeding and labelling with embedded-space graph neural networks in Proc. 6th
Int. Workshop Connecting the Dots. 202 (1900) 0
2007.00149
44 G. DeZoort et al. Charged particle tracking via edge-classifying interaction networks Comput. Softw. Big Sci. 5 (2021) 26 2103.16701
45 S. Van Stroud et al. Transformers for charged particle track reconstruction in high energy physics 2411.07149
46 S. Farrell et al. The HEP.TrkX Project: Deep neural networks for HL-LHC online and offline tracking in Eur. Phys. J. Web Conf., volume 150, 2017
link
47 X. Ju et al. Performance of a geometric deep learning pipeline for HL-LHC particle tracking EPJC 81 (2021) 876 2103.06995
48 S. Miao et al. Locality-sensitive hashing-based efficient point transformer with applications in high-energy physics in st Int. Conference on Machine Learning, volume 235, 2024
Proc. 4 (2024) 35546
2402.12535
49 J. Shlomi et al. Secondary vertex finding in jets with neural networks EPJC 81 (2021) 540 2008.02831
50 S. Van Stroud et al. Secondary vertex reconstruction with MaskFormers EPJC 84 (2024) 1020 2312.12272
51 X. Ju and B. Nachman Supervised jet clustering with graph neural networks for Lorentz boosted bosons PRD 102 (2020) 075014 2008.06064
52 J. Li, T. Li, and F.-Z. Xu Reconstructing boosted Higgs jets from event image segmentation JHEP 04 (2021) 156 2008.13529
53 J. Guo, J. Li, T. Li, and R. Zhang Boosted Higgs boson jet reconstruction via a graph neural network PRD 103 (2021) 116025 2010.05464
54 M. J. Fenton et al. Permutationless many-jet event reconstruction with symmetry preserving attention networks PRD 105 (2022) 112008 2010.09206
55 A. Shmakov et al. SPANet: Generalized permutationless set assignment for particle physics using symmetry preserving attention SciPost Phys. 12 (2022) 178 2106.03898
56 M. J. Fenton et al. Reconstruction of unstable heavy particles using deep symmetry-preserving attention networks Commun. Phys. 7 (2024) 139 2309.01886
57 H. Li et al. Reconstruction of boosted and resolved multi-Higgs-boson events with symmetry-preserving attention networks JHEP 11 (2025) 119 2412.03819
58 S. R. Qasim, J. Kieseler, Y. Iiyama, and M. Pierini Learning representations of irregular particle-detector geometry with distance-weighted graph networks EPJC 79 (2019) 608 1902.07987
59 P. T. Komiske, E. M. Metodiev, B. Nachman, and M. D. Schwartz Pileup mitigation with machine learning (PUMML) JHEP 12 (2017) 051 1707.08600
60 J. Arjona Mart \'\i nez et al. Pileup mitigation at the Large Hadron Collider with graph neural networks Eur. Phys. J. Plus 134 (2019) 333 1810.07988
61 T. Li et al. Semi-supervised graph neural networks for pileup noise removal EPJC 83 (2023) 99 2203.15823
62 CMS Collaboration The phase-2 upgrade of the CMS tracker CMS Technical Design Report CERN-LHCC-2017-009, CMS-TDR-014, 2017
link
63 CMS Collaboration A MIP timing detector for the CMS phase-2 upgrade CMS Technical Design Report CERN-LHCC-2019-003, CMS-TDR-020, 2019
CDS
64 CMS Collaboration The phase-2 upgrade of the CMS level-1 trigger CMS Technical Design Report CERN-LHCC-2020-004, CMS-TDR-021, 2020
CDS
65 CMS Collaboration The phase-2 upgrade of the CMS data acquisition and high level trigger CMS Technical Design Report CERN-LHCC-2021-007, CMS-TDR-022, 2020
CDS
66 CMS Collaboration The phase-2 upgrade of the CMS beam radiation instrumentation and luminosity detectors CMS Technical Design Report CERN-LHCC-2021-008, CMS-TDR-023, 2021
CDS
67 CMS Collaboration The phase-2 upgrade of the CMS barrel calorimeters CMS Technical Design Report CERN-LHCC-2017-011, CMS-TDR-015, 2017
CDS
68 CMS Collaboration The phase-2 upgrade of the CMS endcap calorimeter CMS Technical Design Report CERN-LHCC-2017-023, CMS-TDR-019, 2017
CDS
69 CMS Collaboration The phase-2 upgrade of the CMS muon detectors CMS Technical Design Report CERN-LHCC-2017-012, CMS-TDR-016, 2017
CDS
70 CMS Collaboration The CMS experiment at the CERN LHC JINST 3 (2008) S08004
71 CMS Collaboration Development of the CMS detector for the CERN LHC Run 3 JINST 19 (2024) P05064 CMS-PRF-21-001
2309.05466
72 CMS Collaboration Performance of the CMS Level-1 trigger in proton-proton collisions at $ \sqrt{s} = $ 13 TeV JINST 15 (2020) P10017 CMS-TRG-17-001
2006.10165
73 CMS Collaboration The CMS trigger system JINST 12 (2017) P01020 CMS-TRG-12-001
1609.02366
74 CMS Collaboration Performance of the CMS high-level trigger during LHC Run 2 JINST 19 (2024) P11021 CMS-TRG-19-001
2410.17038
75 CMS Collaboration Electron and photon reconstruction and identification with the CMS experiment at the CERN LHC JINST 16 (2021) P05014 CMS-EGM-17-001
2012.06888
76 CMS Collaboration Performance of the CMS muon detector and muon reconstruction with proton-proton collisions at $ \sqrt{s}= $ 13 TeV JINST 13 (2018) P06015 CMS-MUO-16-001
1804.04528
77 CMS Collaboration Description and performance of track and primary-vertex reconstruction with the CMS tracker JINST 9 (2014) P10009 CMS-TRK-11-001
1405.6569
78 P. Billoir and S. Qian Simultaneous pattern recognition and track fitting by the kalman filtering method NIM A 294 (1990) 219
79 CMS Collaboration Heterogeneous reconstruction of hadronic particle flow clusters with the Alpaka portability library Eur. Phys. J. Web Conf. 337 (2025) 01171
80 M. Cacciari, G. P. Salam, and G. Soyez The anti-$ k_{\mathrm{T}} $ jet clustering algorithm JHEP 04 (2008) 063 0802.1189
81 M. Cacciari, G. P. Salam, and G. Soyez FastJet EPJC 72 (2012) 1896 1111.6097
82 CMS Collaboration Jet energy scale and resolution in the CMS experiment in pp collisions at 8 TeV JINST 12 (2017) P02014 CMS-JME-13-004
1607.03663
83 CMS Collaboration Pileup mitigation at CMS in 13 TeV data JINST 15 (2020) P09018 CMS-JME-18-001
2003.00503
84 D. Bertolini, P. Harris, M. Low, and N. Tran Pileup per particle identification JHEP 10 (2014) 059 1407.6013
85 CMS Collaboration Technical proposal for the Phase-II upgrade of the Compact Muon Solenoid CMS Technical Proposal CERN-LHCC-2015-010, CMS-TDR-15-02, 2015
CDS
86 CMS Collaboration Performance of missing transverse momentum reconstruction in proton-proton collisions at $ \sqrt{s} = $ 13 TeV using the CMS detector JINST 14 (2019) P07004 CMS-JME-17-001
1903.06078
87 C. Bierlich et al. A comprehensive guide to the physics and usage of PYTHIA8.3 SciPost Phys. Codeb, 2022
link
2203.11601
88 CMS Collaboration Extraction and validation of a new set of CMS PYTHIA8 tunes from underlying-event measurements EPJC 80 (2020) 4 CMS-GEN-17-001
1903.12179
89 GEANT4 Collaboration GEANT 4---a simulation toolkit NIM A 506 (2003) 250
90 GEANT4 Collaboration GEANT 4 developments and applications IEEE Trans. Nucl. Sci. 53 (2006) 270
91 GEANT4 Collaboration Recent developments in GEANT 4 NIM A 835 (2016) 186
92 A. Vaswani et al. Attention is all you need in Advances in Neural Information Processing Systems, I. Guyon et al., eds., volume 30, Curran Associates, Inc, 2017
link
1706.03762
93 T.-Y. Lin et al. Focal loss for dense object detection IEEE Trans. Pattern Anal. Mach. Intell. 42 (2020) 318 1708.02002
94 D. Holmberg Jet energy corrections with graph neural network regression PhD thesis, Master's thesis, University of Helsinki, 2022
link
95 T. Dao et al. FLASHATTENTION: Fast and memory-efficient exact attention with IO-awareness in Advances in Neural Information Processing Systems, S. Koyejo et al., eds., volume 35, Curran Associates, Inc, 2022
link
2205.14135
96 R. Xiong et al. On layer normalization in the transformer architecture in Int. Conference on Machine Learning, H. Daumé III and A. Singh, eds., volume 119, PMLR, 1052
Xiong in Proc. 3 (1052) 4
2002.04745
97 J. Pata et al. jpata/particleflow: v2.5.0 link
98 A. Paszke et al. PYTORCH: An imperative style, high-performance deep learning library in Advances in Neural Information Processing Systems, H. Wallach et al., eds., volume 32, Curran Associates, Inc, 2019
link
1912.01703
99 CMS Collaboration A unified approach for jet tagging in Run 3 at $ \sqrt{s}= $ 13.6 TeV in CMS CMS Detector Performance Note CMS-DP-2024-066, 2024
CDS
100 CMS Collaboration Flavour tagging performance of the updated unified particle transformer algorithm with the CMS experiment at $ \sqrt{s}= $ 13.6 TeV CMS Detector Performance Note CMS-DP-2025-081, 2025
CDS
101 CMS Collaboration Jet energy scale and resolution of jets with ParticleNet $ p_{\mathrm{T}} $ regression using Run 3 data collected by the CMS experiment in 2022 and 2023 at 13.6 TeV CMS Detector Performance Note CMS-DP-2024-064, 2024
CDS
102 CMS Collaboration DeepMET: Improving missing transverse momentum estimation with a deep neural network Submitted to Phys. Rev. D, 2025 CMS-JME-24-001
2509.12012
103 CMS Collaboration Jet algorithms performance in 13 TeV data CMS Physics Analysis Summary, 2017
CMS-PAS-JME-16-003
CMS-PAS-JME-16-003
104 CMS Collaboration Open neural network exchange ( ONNX ) \href{ONNX}\url{https://github.com/onnx/onnx. Accessed: -11-02, 2025}
Compact Muon Solenoid
LHC, CERN