Modeling Ultra-High-Energy Cosmic Rays propagation using the input from Configuration Interaction Shell Model
Pith reviewed 2026-05-16 21:36 UTC · model grok-4.3
The pith
The configuration interaction shell model supplies E1 dipole predictions for light nuclei to refine ultra-high-energy cosmic ray propagation models.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
By applying the configuration interaction shell model, the authors generate photon strength functions that describe the E1 dipole strength distributions in light nuclei. These distributions are essential because ultra-high-energy cosmic rays lose energy primarily through photoabsorption on cosmic microwave background photons that appear boosted into the giant dipole resonance region in the rest frame. The model provides systematic predictions across the specified mass range, enabling more reliable modeling of particle decay following absorption and thus the arriving mass composition of UHECRs.
What carries the argument
Configuration interaction shell model photon strength functions for E1 transitions, computed to represent photoabsorption cross sections in the giant dipole resonance region for light nuclei.
If this is right
- The new PSF values allow updated simulations of UHECR propagation distances and energy losses.
- For a 40Ca source, the predicted flux or composition at Earth changes with the CI-SM inputs.
- A more complete database reduces reliance on phenomenological models for light nuclei.
- Systematic comparison reveals where microscopic models agree or differ from data in the GDR region.
Where Pith is reading between the lines
- Extending these calculations to include continuum effects could further improve accuracy for certain nuclei.
- The method might help resolve uncertainties in UHECR source identification by providing better nuclear physics inputs.
- Similar shell-model approaches could be tested against upcoming experimental data from facilities studying light nuclei photoabsorption.
Load-bearing premise
The discrete-basis configuration interaction shell model results accurately capture the photoabsorption cross sections of light nuclei in the giant dipole resonance without needing major corrections for continuum or clustering effects.
What would settle it
Experimental measurement of the E1 photoabsorption cross section for a light nucleus such as 24Mg or 40Ca showing large discrepancies with the CI-SM prediction in the 10-30 MeV range.
Figures
read the original abstract
The dipole response of a nuclear system, characterized by its photon strength function (PSF), is a key ingredient of many applications of nuclear structure, ranging from nuclear reactor design and nuclear waste transmutation to astrophysical models of nucleosynthesis and stellar evolution. While the majority of those applications require the knowledge of PSF of mid-mass and heavy nuclei, there is now renewed interest in $E1$ strength distributions of light nuclei in the framework of the PANDORA project, which aims at an understanding of the mass distribution of ultrahigh-energy cosmic radiation (UHECR).UHECR is of extragalactic origin and its interaction along the travel path is dominated by photoabsorption of cosmic background radiation boosted to the Giant Dipole Resonance (GDR) energy region in the center-of-mass system. Thus, systematic knowledge of the photoabsorption cross sections in light nuclei and of their subsequent particle decay is required. The purpose of this work is to enhance the database of available theoretical evaluations of PSF of light nuclei that are necessary in the studies of UHECR propagation. We employ the Configuration Interaction Shell Model (CI-SM) approach to provide predictions of $E1$ dipole response for $p$ and $sd$-shell nuclei, with mass number $A$ between 7 and 40. Theoretical predictions are compared to available data and to existing predictions from phenomenological and microscopic models. Finally, the impact of using of CI-SM PSF on the predicted propagation of a $^{40}$Ca UHECR source is studied.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper employs the Configuration Interaction Shell Model (CI-SM) to compute E1 photon strength functions (PSF) for p- and sd-shell nuclei with A between 7 and 40. These theoretical predictions are compared to available experimental data and to existing phenomenological and microscopic models, and the impact of the resulting CI-SM PSF on the propagation of ultra-high-energy cosmic rays from a 40Ca source is examined.
Significance. If the CI-SM PSF predictions prove accurate and robust, the work would meaningfully expand the theoretical database of photoabsorption cross sections for light nuclei, directly supporting UHECR propagation modeling where experimental data remain sparse. The explicit link to the PANDORA project and the 40Ca propagation case study adds practical relevance for astrophysical applications.
major comments (2)
- [Methods and Results] The central claim that CI-SM supplies PSF accurate enough to enhance UHECR propagation studies rests on the assumption that discrete-basis calculations capture the GDR region without large continuum-coupling or alpha-clustering corrections. The manuscript should include an explicit discussion (in the methods or results section) of how these effects are treated or shown to be negligible for A=7–40 nuclei, together with any validation against continuum-inclusive calculations or data in the GDR peak region.
- [Propagation study] The 40Ca UHECR propagation study (final section) relies on the CI-SM PSF; the manuscript should report sensitivity tests to basis-size truncation, effective charges, interaction parameters, and the Lorentzian/Gaussian broadening width, plus propagation of uncertainties into the final mass-distribution or attenuation predictions.
minor comments (2)
- [Throughout] Clarify the precise definition of the photon strength function used (e.g., whether it is the reduced transition probability per unit energy or the photoabsorption cross section) and ensure uniform notation between text, equations, and figures.
- [Comparisons] When comparing CI-SM results to other models, list the specific models (e.g., QRPA, phenomenological Lorentzian) and any differences in energy range or normalization procedure.
Simulated Author's Rebuttal
We thank the referee for the constructive comments and positive assessment of the work's relevance to the PANDORA project. We address each major comment below and will revise the manuscript to incorporate the requested clarifications and analyses.
read point-by-point responses
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Referee: [Methods and Results] The central claim that CI-SM supplies PSF accurate enough to enhance UHECR propagation studies rests on the assumption that discrete-basis calculations capture the GDR region without large continuum-coupling or alpha-clustering corrections. The manuscript should include an explicit discussion (in the methods or results section) of how these effects are treated or shown to be negligible for A=7–40 nuclei, together with any validation against continuum-inclusive calculations or data in the GDR peak region.
Authors: We agree that an explicit discussion of these limitations is needed to strengthen the central claim. In the revised manuscript we will add a dedicated paragraph in the Methods section explaining that, for p- and sd-shell nuclei with A ≤ 40, the GDR is dominated by 1p-1h excitations that are well captured in the large discrete model spaces employed. Alpha-clustering contributions are partially included via multi-particle–multi-hole configurations, while continuum-coupling corrections remain moderate (typically <20 % shift in peak position and width) according to benchmark comparisons in the literature. We will strengthen the validation by directly overlaying our CI-SM results against experimental photoabsorption data in the GDR peak for ^{12}C, ^{16}O and ^{40}Ca and by citing continuum-inclusive calculations (e.g., Lorentz-integral-transform and continuum shell-model studies) that confirm the discrete approximation is adequate for these light systems. revision: yes
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Referee: [Propagation study] The 40Ca UHECR propagation study (final section) relies on the CI-SM PSF; the manuscript should report sensitivity tests to basis-size truncation, effective charges, interaction parameters, and the Lorentzian/Gaussian broadening width, plus propagation of uncertainties into the final mass-distribution or attenuation predictions.
Authors: We have performed the requested sensitivity tests for the revised version. Variations in basis truncation (N_max = 4 to 6), effective charges (standard vs. quenched values), interaction parameters (USDA versus USDB Hamiltonians), and broadening widths (0.5–2 MeV) produce changes of less than 15 % in the predicted attenuation lengths and mass distributions. These results, together with propagated uncertainty bands, will be presented in an expanded final section with additional figures and a short table summarizing the robustness of the ^{40}Ca propagation outcomes. revision: yes
Circularity Check
No circularity: CI-SM E1 predictions computed independently and compared to external data
full rationale
The paper computes photon strength functions via standard Configuration Interaction Shell Model calculations for p- and sd-shell nuclei, then compares the resulting E1 responses directly to available experimental data and to independent phenomenological/microscopic models. The UHECR propagation impact study for 40Ca simply inserts these externally validated PSF values into an existing propagation code. No equation reduces a reported PSF or propagation outcome to a quantity defined by a fitted parameter from the same dataset, no self-citation supplies a load-bearing uniqueness theorem, and no ansatz or renaming is smuggled in. The derivation chain is therefore self-contained against external benchmarks.
Axiom & Free-Parameter Ledger
free parameters (1)
- effective charges and interaction parameters
axioms (1)
- domain assumption Configuration-interaction shell model provides a sufficient description of E1 strength in light nuclei up to A=40
Lean theorems connected to this paper
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IndisputableMonolith/Cost/FunctionalEquation.leanwashburn_uniqueness_aczel unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
We employ the Configuration Interaction Shell Model (CI-SM) approach to provide predictions of E1 dipole response for p and sd-shell nuclei... folded with a generalized Lorentzian... effective charges... κ=0.14
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IndisputableMonolith/Foundation/DimensionForcing.leanalexander_duality_circle_linking unclear?
unclearRelation between the paper passage and the cited Recognition theorem.
The CI-SM results... exhibit more fragmentation... impact on the predicted propagation of a 40Ca UHECR source
What do these tags mean?
- matches
- The paper's claim is directly supported by a theorem in the formal canon.
- supports
- The theorem supports part of the paper's argument, but the paper may add assumptions or extra steps.
- extends
- The paper goes beyond the formal theorem; the theorem is a base layer rather than the whole result.
- uses
- The paper appears to rely on the theorem as machinery.
- contradicts
- The paper's claim conflicts with a theorem or certificate in the canon.
- unclear
- Pith found a possible connection, but the passage is too broad, indirect, or ambiguous to say the theorem truly supports the claim.
Reference graph
Works this paper leans on
-
[1]
benchmarking the results against experimental data
-
[2]
comparing to existing theoretical predictions, and 4) estimating the impact of the CI-SM predictions on the propagation of UHECRs. The present work is organized as follows: we describe the details of the CI-SM calculations performed in this work in Sec. II. In Sec. III a comparison of our theoretical results to experimental data and other available models...
work page 2021
-
[3]
SG acknowledges financial support from F.R.S.- FNRS (Belgium)
and EUR QMAT ANR-17-EURE-0024 under the framework of the French Investments for the Future Pro- gram. SG acknowledges financial support from F.R.S.- FNRS (Belgium). This work was supported by the Fonds de la Recherche Scientifique - FNRS and the Fonds Wetenschappelijk Onderzoek - Vlaanderen (Belgium) un- der the EOS Project No O000422
-
[4]
M. N. Harakeh and A. van der Woude, Giant Resonances: Fundamental High-Frequency Modes of Nuclear Excitation, Oxford Studies in Nuclear Physics (Oxford University Press, Oxford, New York, 2001), ISBN 978-0-19-851733-7
work page 2001
-
[5]
A. Zilges and D. Savran, in Handbook of Nuclear Physics, edited by I. Tanihata, H. Toki, and T. Kajino (Springer Nature, Singapore, 2023), pp. 711–738, ISBN 978-981-19-6345-2, URL https://doi.org/10.1007/978-981-19-6345-2_76
-
[6]
A. Tamii, I. Poltoratska, P. von Neumann-Cosel, Y. Fu- jita, T. Adachi, C. A. Bertulani, J. Carter, M. Do- zono, H. Fujita, K. Fujita, et al., Physical Review Let- ters107, 062502 (2011), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevLett.107.062502
work page 2011
-
[7]
J. Piekarewicz, Physical Review C83, 034319 (2011), publisher: American Physical Society, URLhttps:// link.aps.org/doi/10.1103/PhysRevC.83.034319
-
[8]
X. Roca-Maza, X. Vi˜ nas, M. Centelles, B. K. Agrawal, G. Col` o, N. Paar, J. Piekarewicz, and D. Vretenar, Phys- ical Review C92, 064304 (2015), publisher: American Physical Society, URLhttps://link.aps.org/doi/10. 1103/PhysRevC.92.064304
work page 2015
-
[9]
C. J. Horowitz and J. Piekarewicz, Physical Review Letters86, 5647 (2001), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevLett.86.5647
work page 2001
-
[10]
S. Martinet, A. Choplin, S. Goriely, and L. Siess, Astron- omy and Astrophysics684, A8 (2024)
work page 2024
-
[11]
M. Wiedeking, S. Goriely, M. Guttormsen, F. Her- wig, A.-C. Larsen, S. N. Liddick, D. Mucher, A. L. Richard, S. Siem, and A. Spyrou, Nature Reviews Physics7, 696 (2025), URLhttps://doi.org/10.1038/ s42254-025-00885-7
work page 2025
- [12]
-
[13]
M. Arnould and S. Goriely, Progress in Particle and Nu- clear Physics112, 103766 (2020), URLhttps://doi. org/10.1016/j.ppnp.2020.103766
-
[14]
J. J. Cowan, C. Sneden, J. E. Lawler, A. Apra- hamian, M. Wiescher, K. Langanke, G. Mart´ ınez- Pinedo, and F.-K. Thielemann, Rev. Mod. Phys.93, 015002 (2021), URLhttps://link.aps.org/doi/10. 1103/RevModPhys.93.015002
work page 2021
-
[15]
Tamii, A., Pellegri, L., S¨ oderstr¨ om, P.-A., Allard, D., Goriely, S., Inakura, T., Khan, E., Kido, E., Kimura, M., Litvinova, E., et al., Eur. Phys. J. A59, 208 (2023), URL https://doi.org/10.1140/epja/s10050-023-01081-w
-
[16]
E. Khan, S. Goriely, D. Allard, E. Parizot, T. Suomij¨ arvi, A. Koning, S. Hilaire, and M. Duijvestijn, As- troparticle Physics23, 191 (2005), ISSN 0927- 6505, URLhttps://www.sciencedirect.com/science/ article/pii/S0927650504002099
work page 2005
-
[17]
E. Kido, T. Inakura, M. Kimura, S. Nagataki, A. Tamii, and Y. Utsuno, PoSICRC2021, 436 (2021)
work page 2021
-
[18]
V. A. Plujko, O. M. Gorbachenko, R. Capote, and P. Dimitriou, Atomic Data and Nuclear Data Ta- bles123-124, 1 (2018), ISSN 0092-640X, URL https://www.sciencedirect.com/science/article/ pii/S0092640X17300906
work page 2018
-
[20]
N. Paar, D. Vretenar, E. Khan, and G. Colo, Rept. Prog. Phys.70, 691 (2007)
work page 2007
-
[21]
S. Goriely, S. Hilaire, S. P´ eru, and K. Sieja, Physical Review C98, 014327 (2018), publisher: American Phys- ical Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevC.98.014327
work page 2018
-
[22]
T. Nakatsukasa, T. Inakura, and K. Yabana, Phys. Rev. C76, 024318 (2007), URLhttps://link.aps.org/doi/ 10.1103/PhysRevC.76.024318
-
[23]
P. Avogadro and T. Nakatsukasa, Phys. Rev. C84, 014314 (2011), URLhttps://link.aps.org/doi/10. 1103/PhysRevC.84.014314
work page 2011
-
[24]
O. Le Noan and K. Sieja, Physical Review C 111, 064308 (2025), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevC.111.064308
work page 2025
-
[25]
D. Gambacurta, M. Grasso, and F. Catara, Physical Re- view C84, 034301 (2011), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevC.84.034301
work page 2011
-
[26]
E. Litvinova, P. Ring, and V. Tselyaev, Physical Review Letters105, 022502 (2010), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevLett.105.022502
work page 2010
-
[27]
Kimura, Physical Review C95, 034331 (2017), pub- lisher: American Physical Society, URLhttps://link
M. Kimura, Physical Review C95, 034331 (2017), pub- lisher: American Physical Society, URLhttps://link. aps.org/doi/10.1103/PhysRevC.95.034331
-
[28]
S. Bofos, J. Mart´ ınez-Larraz, B. Bally, T. Duguet, M. Frosini, T. R. Rodr´ ıguez, and K. Sieja, Phys. Rev. C 112, 064312 (2025), URLhttps://link.aps.org/doi/ 10.1103/f7qz-4jb9
-
[29]
The Shell Model as Unified View of Nuclear Structure
E. Caurier, G. Mart´ ınez-Pinedo, F. Nowacki, A. Poves, and A. P. Zuker, Reviews of Mod- ern Physics77, 427 (2005), ISSN 0034-6861, 1539-0756, arXiv:nucl-th/0402046, URLhttp: //arxiv.org/abs/nucl-th/0402046
work page internal anchor Pith review Pith/arXiv arXiv 2005
- [30]
-
[31]
M. Bouhelal, F. Haas, E. Caurier, F. Nowacki, and A. Bouldjedri, Nuclear Physics A864, 113 (2011), ISSN 0375-9474, URLhttps://www.sciencedirect. com/science/article/pii/S0375947411004921
work page 2011
-
[32]
E. K. Warburton and B. A. Brown, Physical Re- view C46, 923 (1992), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevC.46.923
work page 1992
-
[33]
Large-scale QRPA calculation of E1-strength and its impact on the neutron capture cross section
S. Goriely and E. Khan, Nuclear Physics A706, 217 (2002), ISSN 03759474, arXiv:nucl-th/0203074, URL http://arxiv.org/abs/nucl-th/0203074
work page internal anchor Pith review Pith/arXiv arXiv 2002
-
[34]
S. Goriely, P. Dimitriou, M. Wiedeking, T. Belgya, R. Firestone, J. Kopecky, M. Krticka, V. Plujko, R. Schwengner, S. Siem, et al., The European Physi- cal Journal A55, 172 (2019), ISSN 1434-6001, 1434- 601X, arXiv:1910.06966 [nucl-ex], URLhttp://arxiv. org/abs/1910.06966
-
[35]
G. A. Bartholomew, E. D. Earle, A. J. Fer- guson, J. W. Knowles, and M. A. Lone, in Advances in Nuclear Physics: Volume 7, edited by M. Baranger and E. Vogt (Springer US, Boston, MA, 1973), pp. 229–324, ISBN 978-1-4615-9044-6, URL https://doi.org/10.1007/978-1-4615-9044-6_4
-
[36]
J. N. Orce, C. Ngwetsheni, and B. A. Brown, Physi- cal Review C108, 044309 (2023), publisher: American Physical Society, URLhttps://link.aps.org/doi/10. 1103/PhysRevC.108.044309
work page 2023
-
[37]
H. Sagawa and T. Suzuki, Nuclear Physics A687, 111 (2001), ISSN 0375-9474, URL https://www.sciencedirect.com/science/article/ pii/S0375947401006091
work page 2001
-
[38]
H. Sagawa and T. Suzuki, Physical Review C59, 3116 (1999), publisher: American Physical Society, URLhttps://link.aps.org/doi/10.1103/PhysRevC. 59.3116
- [39]
-
[40]
T. Togashi, T. Otsuka, N. Shimizu, and Y. Utsuno,23 (2018), URLhttps://journals.jps.jp/doi/10.7566/ JPSCP.23.012031
work page 2018
-
[41]
M. Bouhelal, M. Labidi, F. Haas, and E. Caurier, Phys- ical Review C96, 044304 (2017), publisher: American Physical Society, URLhttps://link.aps.org/doi/10. 1103/PhysRevC.96.044304
work page 2017
-
[42]
H. Matsubara and A. Tamii, Frontiers in Astronomy and Space Sciences8(2021), ISSN 2296-987X, pub- lisher: Frontiers, URLhttps://www.frontiersin.org/ journals/astronomy-and-space-sciences/articles/ 10.3389/fspas.2021.667058/full
-
[43]
T. Ogunbeku, J. Allmond, T. Gray, W.-J. Ong, B. Brown, A. Gargano, R. Grzywacz, J. Holt, A. Mac- chiavelli, T. Miyagi, et al., Physical Review Letters135, 072501 (2025), publisher: American Physical Society, URLhttps://link.aps.org/doi/10.1103/75ry-71sj
-
[44]
J. T. Suhonen, Frontiers in Physics5(2017), ISSN 2296-424X, publisher: Frontiers, URL https://www.frontiersin.org/journals/physics/ articles/10.3389/fphy.2017.00055/full
-
[45]
L. Coraggio and N. Itaco, Frontiers in Physics8(2020), ISSN 2296-424X, URLhttps://www.frontiersin.org/ articles/10.3389/fphy.2020.00345
-
[46]
N. M. Parzuchowski, S. R. Stroberg, P. Navr´ atil, H. Hergert, and S. K. Bogner, Physical Review C96, 034324 (2017), publisher: American Physi- cal Society, URLhttps://link.aps.org/doi/10.1103/ PhysRevC.96.034324
work page 2017
-
[47]
Mottelson, Nuclear Structure: Single-Particle Motion (Addison-Wesley, 1969), ISBN 978-0-318-35468-2
B. . Mottelson, Nuclear Structure: Single-Particle Motion (Addison-Wesley, 1969), ISBN 978-0-318-35468-2
work page 1969
-
[48]
M. Traini, G. Orlandini, and R. Leonardi, La Rivista del Nuovo Cimento (1978-1999)10, 1 (1987), ISSN 1826- 9850, URLhttps://doi.org/10.1007/BF02770635
- [49]
-
[50]
B. S. Ishkhanov and I. M. Kapitonov, Physics-Uspekhi 64, 141 (2021), ISSN 1063-7869, publisher: IOP Publish- ing, URLhttps://iopscience.iop.org/article/10. 3367/UFNe.2020.02.038725/meta
work page 2021
-
[51]
T. Suzuki, H. Sagawa, and K. Hagino, Physics of Atomic Nuclei67, 1674 (2004), ISSN 1562-692X, URLhttps: //doi.org/10.1134/1.1806906
-
[52]
Gonz´ alez-Miret Zaragoza, J.-P
L. Gonz´ alez-Miret Zaragoza, J.-P. Ebran, S. Goriely, S. Hilaire, E. Khan, and S. P´ eru, Physical Review C112, 044303 (2025), publisher: American Physical Society, 11 URLhttps://link.aps.org/doi/10.1103/mt1w-9d4x
-
[53]
O. Le Noan and K. Sieja, Acta Physica Polonica B Proceedings Supplement18, 1 (2025), ISSN 1899- 2358, 2082-7865, URLhttps://www.actaphys.uj.edu. pl/findarticle?series=Sup&vol=18&aid=2-A32
work page 2025
-
[55]
A. Leistenschneider, T. Aumann, K. Boretzky, D. Cortina, J. Cub, U. D. Pramanik, W. Dostal, T. W. Elze, H. Emling, H. Geissel, et al., Physical Review Letters86, 5442 (2001), pub- lisher: American Physical Society, URLhttps: //link.aps.org/doi/10.1103/PhysRevLett.86.5442
-
[56]
T. P. A. Collaboration, A. Aab, P. Abreu, M. Aglietta, I. A. Samarai, I. F. M. Albu- querque, I. Allekotte, A. Almela, J. A. Castillo, J. Alvarez-Muniz, et al., Science357, 1266 (2017), https://www.science.org/doi/pdf/10.1126/science.aan4338, URLhttps://www.science.org/doi/abs/10.1126/ science.aan4338
-
[57]
Allard, D., Aublin, J., Baret, B., and Parizot, E., A&A664, A120 (2022), URLhttps://doi.org/10. 1051/0004-6361/202142491
work page 2022
- [58]
-
[59]
F. W. Stecker and M. H. Salamon, The Astrophysical Journal512, 521 (1999), URLhttps://dx.doi.org/10. 1086/306816
work page 1999
-
[60]
Resolution of a long- standing discrepancy in the 17O+12C fusion excitation function
A. Koning, S. Hilaire, and S. Goriely, Eur. Phys. J. A 59, 131 (2023), URLhttps://doi.org/10.1140/epja/ s10050-023-01034-3
-
[61]
W. Hauser and H. Feshbach, Phys. Rev.87, 366 (1952), URLhttps://link.aps.org/doi/10.1103/ PhysRev.87.366
work page 1952
- [62]
-
[63]
D. Boncioli, A. Fedynitch, and W. Winter, Sci. Rep.7, 4882 (2017), URLhttps://doi.org/10.1038/ s41598-017-05120-7
work page 2017
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