Ab initio evidence for surface-dominated antiproton annihilation in ${}^4 \mathrm{He}$

Alireza Dehghani; Guillaume Hupin; Petr Navr\'atil; Sofia Quaglioni

REVIEW

Ab initio evidence for surface-dominated antiproton annihilation in ${}^4 \mathrm{He}$

Alireza Dehghani, Guillaume Hupin, Sofia Quaglioni, Petr Navrátil

Nuclear Theory · Submitted 17 Aug 2026 · 35 references

Pith's verdict: A credible NCSM/RGM study that plausibly shows peripheral annihilation in pbar-4He, but the central claim inherits the assumed short-range annihilation potential, so the 'ab initio' label is doing heavy lifting.

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arXiv ID2608.16552 (version 1)

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CitationAlireza Dehghani, Guillaume Hupin, Petr Navr\'atil, Sofia Quaglioni. "Ab initio evidence for surface-dominated antiproton annihilation in ${}^4 \mathrm{He}$." arXiv:2608.16552 (2026). https://pith.science/paper/GIVIWMZN

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Editor's note

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The genuinely new thing here is the first microscopic annihilation density for antiprotonic 4He, computed with NCSM/RGM and validated against the available scattering and atomic data. The conclusion that annihilation peaks in the tail of the target density, around r = 2 fm, and is suppressed for r < 1 fm, is exactly the assumption behind the PUMA program, so the paper gives that program a welcome, concrete test in a tightly bound nucleus. The validations are real: reaction cross sections, elastic differential cross sections, and the 2P level shifts are all in reasonable shape, and the Nmax and regulator convergence checks in the appendix are appropriate. The SRG analysis is a reasonable way to show that the low-energy part of the kernel reproduces the peripheral peak, though it does not remove the basic sensitivity problem.

The soft spot is the one the stress-test note puts its finger on, and I think it lands. The annihilation density is computed with the Kohno-Weise optical potential, whose imaginary part is a fitted Woods-Saxon core. The strong-interaction kernel is negligible beyond about 2 fm, so the peripheral peak at r about 2 fm is largely a property of the assumed short-range annihilation interaction, not an independent prediction of the nuclear many-body calculation. The validations against cross sections and level shifts constrain the integrated absorption strength but have limited sensitivity to the radial distribution of annihilation. The paper itself acknowledges that the annihilation density is not an observable and that the SRG remedy does not necessarily preserve detailed features, which is honest, but it stops short of testing an alternative NbarN model. Given the authors' own Ref. [21] compares several optical models, recomputing gamma_a with even one of those alternatives would have turned a conditional result into a much stronger one. The factor-of-two discrepancy with Schneider et al. in the real part of the level shift is a secondary concern, but it reinforces the point that the optical potential is not yet under control.

The label 'ab initio' also overstates the status of the annihilation potential: the 4He structure and the scattering framework are ab initio, but the short-range annihilation physics is phenomenological. That is not a fatal flaw, but it should be said plainly in the paper.

Who is this for? People working on antiprotonic atoms, PUMA, and optical models of low-energy antinucleon-nucleus interactions. The paper deserves a serious referee; the numerics look careful, the framework is established, and the question is directly relevant to an active experimental program. My recommendation is to engage with it, but send it back for a sensitivity study with alternative NbarN models and an uncertainty estimate on the annihilation density.

Referee report

Significance

The paper addresses a question directly relevant to planned CERN/AD experiments, namely whether low-energy antiproton annihilation is peripheral. The NCSM/RGM calculation is a genuine microscopic reaction treatment rather than a purely phenomenological optical-model fit, and the cross-section and atomic-data validations in Figs. 2-4, together with the Nmax and regulator-dependence estimates in the Appendix, give the framework nontrivial credibility. The paper also deserves credit for explicitly acknowledging that gamma_a is representation dependent and for attempting to address this with an SRG analysis. If the peripheral character of gamma_a is robust against changes in the NbarN interaction, the result would strengthen the physics case for PUMA and related surface probes; the sensitivity analysis needed to establish that robustness is the main missing piece.

Major objections (4)

[NbarN interaction (p.2), Figs. 1-5] The central result, the peripheral peak of gamma_a at r ≈ 2 fm, is largely inherited from the short-range imaginary Woods-Saxon core of the KW potential rather than being an independent prediction of the many-body calculation. The strong-interaction kernel is negligible beyond r,r' ≈ 2 fm (Fig. 1), and the validations in Figs. 2-3 constrain the integrated absorption strength but not its radial distribution; the real part of the 2P level shift disagrees with Schneider et al. by roughly a factor of two (Fig. 4). To support the claim that peripheral annihilation is a property of the physical system, the authors should recompute gamma_a with at least one alternative NbarN optical model, such as those compared in Ref. [21], or perform a controlled variation of the range and depth of the imaginary core.
[Annihilation density section, Fig. 5] No uncertainty estimate is provided for the annihilation density gamma_a itself, in contrast to the scattering length and level shifts where regulator uncertainties are quoted (Tables I-III). The top panel of Fig. 5 shows Nmax = 26, 28, and 30 curves but no band and no statement of sensitivity to r_reg = 7 fm and r_reg,c = 5 fm, even though the regulator dependence is identified in the Appendix as a systematic uncertainty. Without a quantitative uncertainty on gamma_a, the statements that it peaks around r ≈ 2 fm and is negligible for r < 1 fm are not supported at the same standard as the other observables.
[SRG paragraph, bottom panel of Fig. 5] The SRG analysis is performed at a single flow parameter lambda = 2.6 fm^-1 and a single truncation Ncut = 20, and the paper explicitly notes that the SRG-based remedy does not necessarily preserve the detailed qualitative features because gamma_a is not an observable. This leaves open the possibility that the apparent displacement of annihilation strength to larger r is an artifact of the particular SRG evolution rather than a physically robust feature. The authors should test at least one additional lambda value and demonstrate convergence in Ncut to show that the low-energy localization is representation independent.
[Fig. 4 and surrounding text] The real part of the averaged 2P level shift is consistent with Davies et al. but differs by roughly a factor of two from Schneider et al. Since the annihilation density is sensitive to the tail of the atomic wave function, which is precisely what the real level shift constrains, this factor-of-two ambiguity should be propagated into the uncertainty of gamma_a; at present it is not.

Minor objections (5)

[Abstract, first sentence] The abstract contains a typo: 'ab initiono-core shell model' should read 'ab initio no-core shell model'.
[Fig. 5 caption] The dotted line for the target density is described as 'scaled', but the scale factor is not given; please state it or remove the scaling.
[Fig. 6 and surrounding text] The isospin decomposition would benefit from a derivation of the factors 1/3 and 2/3 used for gamma_pbarp and gamma_nbarp; the conclusion that the pbar-p and nbar-p contributions are identical is not self-evident and deserves an explicit explanation.
[Figs. 2 and 3 captions] The notation Nmax = 26(27) and Nmax = 22(23) is not defined explicitly in the captions; please add a sentence explaining that the values in parentheses correspond to positive-parity states.
[Table III and surrounding text] The channel radius ac = 400 fm is used for the 2P level-shift calculation without a convergence check with respect to ac; a sentence stating that the results are independent of ac would be useful.

How Pith checks papers → · Full audit of this paper →

The paper

The paper claims

Antiproton annihilation in the lowest 4He atomic state peaks at the nuclear surface, not the interior.

The reading

This paper asks whether the standard picture of antiprotonic-atom experiments is right for a tightly bound nucleus: do low-energy antiprotons annihilate mainly at the nuclear periphery, where the density tail lives? The authors answer yes for ${}^{4}\mathrm{He}$, the lightest tightly bound nucleus, using a microscopic reaction calculation that couples an ab initio no-core shell model description of the helium target to the antiproton's relative motion. They find that the annihilation density is negligible for separations $r<1$ fm and peaks near $r\approx 2$ fm, in the tail of the ${}^{4}\mathrm{He}$ density, and they show with a similarity renormalization group analysis that the low-energy annihilation strength stays at large intercluster distances. The result matters because it justifies using antiproton absorption as a surface probe of nuclear structure, such as halos and neutron skins.

What carries the argument

The load-bearing object is the annihilation density $\gamma_a(r)$, the radial annihilation strength per unit length as a function of the separation between the antiproton and the center of mass of ${}^{4}\mathrm{He}$. It is built from the relative-motion wave function of the lowest atomic state together with the imaginary part of the strong-interaction kernel in the NCSM/RGM reaction framework: an ab initio no-core shell model wave function of the target is folded with a phenomenological optical antiproton-nucleon potential, producing a nonlocal kernel that is already negligible by $r,r'\approx 2$ fm. A similarity renormalization group transformation then decouples the high- and low-$n$ harmonic-oscillator components of this Hamiltonian, letting the authors isolate the low-energy content of the annihilation density and show that it remains peaked at large distances.

Extended reading notes

Core claim

On its own terms, the paper's central claim is that in the lowest atomic state of antiprotonic ${}^{4}\mathrm{He}$, the annihilation process is surface-dominated. The microscopic annihilation density $\gamma_a(r)$ is strongly suppressed inside the nucleus ($r<1$ fm) and reaches its maximum at $r\approx 2$ fm, on the tail of the target density. This qualitative picture is preserved when a similarity renormalization group transformation decouples the low- and high-momentum pieces of the Hamiltonian: the low-energy annihilation strength remains localized at large intercluster distances, so the peripheral character is not an artifact of high harmonic-oscillator components. Before drawing this conclusion, the authors check the same Hamiltonian against measured reaction cross sections, elastic differential cross sections, and antiprotonic-atom level shifts and widths, finding consistency within the uncertainties of the optical potential and regulator parameters.

Load-bearing premise

The peripheral character of the result is inherited from the spatial range of the imaginary core of the adopted optical potential; if a different antinucleon-nucleon annihilation model placed more annihilation strength inside $r\approx 1$ fm, the surface-dominated claim would weaken.

Editorial extensions

If this is right

If the calculation is right, the phenomenological assumption behind antiprotonic-atom experiments holds for the lightest tightly bound nucleus: annihilation probes the tail of the nuclear density rather than the bulk.
At $r<1$ fm the annihilation strength is negligible, so the suppression of interior annihilation is quantitative and can be computed microscopically for other targets.
The SRG analysis removes the numerical oscillations in the density tail without changing the peripheral peak, indicating that the conclusion is stable against the model-space truncation.
The equal $T=0$ and $T=1$ contributions to the annihilation density mean the adopted optical potential cannot distinguish proton versus neutron annihilation; an isospin-dependent annihilation interaction would be needed for such surface-sensitive studies.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

A direct extension of the paper's logic: for heavier tightly bound nuclei the same calculation would predict a persistent peripheral annihilation, so measured antiprotonic level shifts and widths could be inverted to extract density tails with microscopic uncertainty estimates.
The paper leaves the choice of antinucleon-nucleon model untested; repeating the calculation with an alternative optical model, such as those surveyed in Ref. [21], is the cleanest check of whether the peak at $r\approx 2$ fm is a property of the reaction or an artifact of the potential's imaginary core.
Because the annihilation density is not an observable, experiments constrain only integrated quantities like level widths and cross sections; combining those integrated data with the computed density would give a more direct mapping between measurements and the nuclear-surface sensitivity that antiproton-surface-probe experiments hope to exploit.

Original abstract

Low-energy antiproton beams at CERN/AD open the possibility of probing exotic nuclear structure through annihilation at the nuclear surface. The use of antiprotons as the probe for the nuclear surface is based on the assumption that the annihilation takes place at the periphery of the target. We test this idea for the lightest tightly bound nucleus, i.e., ${}^4 \mathrm{He}$, using the ab initio no-core shell model combined with the resonating group method (NCSM/RGM), adapted to antiproton-nucleus dynamics. After validating our microscopic calculations against available atomic and scattering data, we use the microscopic annihilation density to examine where annihilation occurs inside the antiprotonic atom. We find that the annihilation peaks in the tail of the ${}^{4}\mathrm{He}$ density, around $r\approx 2$ fm, and is strongly suppressed in the nuclear interior. Although this density is representation dependent, a similarity renormalization group (SRG) analysis of the NCSM/RGM Hamiltonian shows that the low-energy annihilation strength remains localized at large intercluster distances. These results support the phenomenological picture underlying antiprotonic-atom experiments: in a tightly bound system such as ${}^{4}\mathrm{He}$, antiproton annihilation is predominantly peripheral and is therefore sensitive to the nuclear-density tail.

The compiled record

The paper's own sentences, arranged, kept beside the review and separate from it. Each label is drawn from a closed vocabulary; the number beside it is the probability the classifier gave that label. Numbers in the tables are the authors', checked by code. No sentence in this record was written by a model.

Compiled by classifier-1.13.0 via TypeSafe API, question bank abstract-p1-20260923, 2026-09-23: 1 request, 5,913 input tokens.

What the abstract itself states, as probabilities: claims first 0.06 · states limitation 0.81 · human participants 0.01 · controlled comparison 0.06 · randomized assignment 0.01 · states quantitative result 0.89 · compares with prior results 0.61 · mentions code or data availability 0.02.

The abstract, sentence by sentence

arXiv listing abstract v1. Results and the main claim are underlined; show every role.

Low-energy antiproton beams at CERN/AD open the possibility of probing exotic nuclear structure through annihilation at the nuclear surface. The use of antiprotons as the probe for the nuclear surface is based on the assumption that the annihilation takes place at the periphery of the target. We test this idea for the lightest tightly bound nucleus, i.e., ${}^4 \mathrm{He}$, using the ab initio no-core shell model combined with the resonating group method (NCSM/RGM), adapted to antiproton-nucleus dynamics. After validating our microscopic calculations against available atomic and scattering data, we use the microscopic annihilation density to examine where annihilation occurs inside the antiprotonic atom. We find that the annihilation peaks in the tail of the ${}^{4}\mathrm{He}$ density, around $r\approx 2$ fm, and is strongly suppressed in the nuclear interior. Although this density is representation dependent, a similarity renormalization group (SRG) analysis of the NCSM/RGM Hamiltonian shows that the low-energy annihilation strength remains localized at large intercluster distances. These results support the phenomenological picture underlying antiprotonic-atom experiments: in a tightly bound system such as ${}^{4}\mathrm{He}$, antiproton annihilation is predominantly peripheral and is therefore sensitive to the nuclear-density tail.

background contribution method result interpretation main claim

What the classifier reports for each sentence. The number is the probability it gave the label.
#	sentence	role	the authors' own work	states the main conclusion	strength
s0	Low-energy antiproton beams at CERN/AD open the possibility of probing exotic nuclear structure through annihilation at the nuclear surface.	background 1.00	0.06	0.03	hedged possibility 0.97
s1	The use of antiprotons as the probe for the nuclear surface is based on the assumption that the annihilation takes place at the periphery of the target.	background 1.00	0.04	0.03	asserted 0.95
s2	We test this idea for the lightest tightly bound nucleus, i.e., ${}^4 \mathrm{He}$, using the ab initio no-core shell model combined with the resonating group method (NCSM/RGM), adapted to antiproton-nucleus dynamics.	method 0.87	0.92	0.03	asserted 0.94
s3	After validating our microscopic calculations against available atomic and scattering data, we use the microscopic annihilation density to examine where annihilation occurs inside the antiprotonic atom.	method 0.94	0.94	0.03	asserted 0.67
s4	We find that the annihilation peaks in the tail of the ${}^{4}\mathrm{He}$ density, around $r\approx 2$ fm, and is strongly suppressed in the nuclear interior.	result 1.00	0.97	0.70	asserted 1.00
s5	Although this density is representation dependent, a similarity renormalization group (SRG) analysis of the NCSM/RGM Hamiltonian shows that the low-energy annihilation strength remains localized at large intercluster distances.	result 0.72	0.94	0.10	asserted 0.99
s6	These results support the phenomenological picture underlying antiprotonic-atom experiments: in a tightly bound system such as ${}^{4}\mathrm{He}$, antiproton annihilation is predominantly peripheral and is therefore sensitive to the nuclear-density tail.	interpretation 1.00	0.67	0.93	asserted 0.77

What kind of paper the classifier reports this is: simulation study 0.81 · evidence from simulation or computation 1.00.

What was examined, and what was not

sources read

arXiv listing abstract v1

not examined

full text
figures and tables
references and citing sentences
relations to other papers

levels run

P abstract

not run

S sections
T body sentences
C citations
R cross-paper relations

Every quoted sentence on this record is the authors'. Every label is from Pith's closed vocabulary, with the probability shown beside it. Every number in the measurements table is the authors', checked by code. Record as JSON

Figures

**Figure 1.** FIG. 1. Real (top) and imaginary (bottom) parts of the

**Figure 4.** FIG. 4. Comparison of our averaged ¯p

**Figure 6.** , where we also display the separate T = 0 and T = 1 contributions (dashed and solid curves). One may be tempted to interpret this result as indicating an equal number of annihilations of protons and neutrons. The KW optical potential employs an imaginary part that is independent of energy and spin-isospin channel. A more quantitative extraction of proton and neutron annihilation components would therefore require a more involved annihilation potential. In summary, we presented an ab initio study of the p¯- 4He system within the NCSM/RGM framework. After establishing that our resul

**Figure 7.** FIG. 7. Real (green) and imaginary (magenta) ¯p

Showing 4 of the paper's 7 figures. See all figures in the PDF ↗ Figures reproduced from arXiv:2608.16552 by the authors.

References

Works cited (35)

[21]

J. Carbonell, G. Hupin, and S. Wycech, Comparison of ¯NNoptical models, Eur. Phys. J. A59, 259 (2023), arXiv:2309.14831 [nucl-th]

View on Pith Pith review arXiv 2023
[1]

R. Caravitaet al., CERN AD/ELENA antimatter pro- gram (2025), arXiv:2503.22471 [nucl-ex]

View on Pith Pith review arXiv 2025
[2]

P.-Y. Duerinck and R. Lazauskas,Ab initiodescription of ¯p+ 3H and ¯p+ 3He systems in optical models, Phys. Rev. C113, 054003 (2026), arXiv:2601.06541 [nucl-th]

View on Pith arXiv 2026
[3]

P.-Y. Duerinck, R. Lazauskas, and J. Dohet-Eraly, Antiproton-deuteron hydrogenic states from a coupled- channel approach, Phys. Rev. C108, 054003 (2023)

View on Pith 2023
[4]

M. Vorabbi, M. Gennari, P. Finelli, C. Giusti, and P. Navr´ atil, Elastic antiproton-nucleus scattering from chiral forces, Phys. Rev. Lett.124, 162501 (2020), arXiv:1906.11984 [nucl-th]

View on Pith Pith review arXiv 2020
[5]

T. Aumannet al.(PUMA), PUMA, antiProton unstable matter annihilation, Eur. Phys. J. A58, 88 (2022)

View on Pith 2022
[6]

A. Trzcinskaet al., Neutron density distributions de- duced from antiprotonic atoms, Phys. Rev. Lett.87, 082501 (2001)

View on Pith 2001
[7]

P. Lubinskiet al., Composition of the nuclear periph- ery from antiproton absorption, Phys. Rev. C57, 2962 (1998), arXiv:nucl-ex/9808005

View on Pith Pith review arXiv 1998
[8]

B. R. Barrett, P. Navr´ atil, and J. P. Vary,Ab initiono core shell model, Prog. Part. Nucl. Phys.69, 131 (2013)

View on Pith 2013
[9]

P. Navr´ atil, G. P. Kamuntavicius, and B. R. Barrett, Few nucleon systems in translationally invariant har- monic oscillator basis, Phys. Rev. C61, 044001 (2000), arXiv:nucl-th/9907054

View on Pith Pith review arXiv 2000
[10]

P. Navratil,Ab initiono-core shell model calculations for light nuclei, in169th Course of International School of Physics ‘Enrico Fermi’: Nuclear Structure far from Stability: New Physics and New Technology(IOS, Ams- terdam, 2007) pp. 147–183, arXiv:0711.2702 [nucl-th]

View on Pith Pith review arXiv 2007
[11]

S. Quaglioni and P. Navr´ atil,Ab initiomany-body cal- culations ofn- 3H,n- 4He,p- 3,4He andn- 10Be scattering, Phys. Rev. Lett.101, 092501 (2008), arXiv:0804.1560 [nucl-th]

View on Pith Pith review arXiv 2008
[12]

S. Quaglioni and P. Navr´ atil,Ab initiomany-body cal- culations of nucleon-nucleus scattering, Phys. Rev. C79, 044606 (2009), arXiv:0901.0950 [nucl-th]

View on Pith Pith review arXiv 2009
[13]

P. Navr´ atil, S. Quaglioni, G. Hupin, C. Romero-Redondo, and A. Calci, Unifiedab initioapproaches to nuclear structure and reactions, Phys. Scripta91, 053002 (2016), arXiv:1601.03765 [nucl-th]

View on Pith Pith review arXiv 2016
[14]

A. Dehghani, G. Hupin, S. Quaglioni, and P. Navr´ atil, Light antiproton-nucleus systems at low energies with theab initioNCSM/RGM method, Phys. Rev. C114, 014613 (2026), arXiv:2602.18162 [nucl-th]

View on Pith Pith review arXiv 2026
[15]

P. Descouvemont and D. Baye, TheR-matrix theory, Rept. Prog. Phys.73, 036301 (2010), arXiv:1001.0678 [nucl-th]

View on Pith Pith review arXiv 2010
[16]

M. Hesse, J. M. Sparenberg, F. Van Raemdonck, and D. Baye, Coupled-channelR-matrix method on a La- grange mesh, Nucl. Phys. A640, 37 (1998)

View on Pith 1998
[17]

D. R. Entem and R. Machleidt, Accurate charge depen- dent nucleon nucleon potential at fourth order of chiral perturbation theory, Phys. Rev. C68, 041001 (2003), arXiv:nucl-th/0304018

View on Pith Pith review arXiv 2003
[18]

M. Kohno and W. Weise, Proton-antiproton scattering and annihilation into two mesons, Nucl. Phys. A454, 429 (1986)

View on Pith 1986
[19]

T. Ueda, Antinucleon-nucleon potentials for bound and scattering states, Prog. Theor. Phys.62, 1670 (1979)

View on Pith 1979
[20]

J.-M. Richard, Antiproton physics, Front. in Phys.8, 6 (2020), arXiv:1912.07385 [nucl-th]

View on Pith Pith review arXiv 2020
[22]

F. Balestraet al., Antiproton-helium annihilation around 44 MeV/c, Phys. Lett. B230, 36 (1989)

View on Pith 1989
[23]

A. Zenoniet al., ¯pDand ¯p4He annihilation cross-sections at very low-energy, Phys. Lett. B461, 413 (1999)

View on Pith 1999
[24]

F. Balestraet al., Antiproton- 4He interactions at 200 MeV/c, Phys. Lett. B305, 18 (1993)

View on Pith 1993
[25]

C. J. Batty, E. Friedman, and A. Gal, Strong interac- tion physics from hadronic atoms, Phys. Rept.287, 385 (1997)

View on Pith 1997
[26]

J. D. Davieset al., Measurement of strong interaction effects in antiprotonic helium atoms, Phys. Lett. B145, 319 (1984)

View on Pith 1984
[27]

M. Schneideret al., X-rays from antiprotonic 3He and 4He, Z. Phys. A338, 217 (1991)

View on Pith 1991
[28]

P. Navr´ atil, Translationally invariant density, Phys. Rev. C70, 014317 (2004)

View on Pith 2004
[29]

A. Dehghani,Reactions with antiprotons in the theory of cold nuclear collisions, Ph.D. thesis, Paris-Saclay Univer- sity (2025), https://theses.hal.science/tel-05398592

View on Pith 2025
[30]

S. K. Bogner, R. J. Furnstahl, and R. J. Perry, Similarity renormalization group for nucleon-nucleon interactions, Phys. Rev. C75, 061001 (2007)

View on Pith 2007
[31]

S. Bogner, R. Furnstahl, and R. Perry, Three-body forces produced by a similarity renormalization group transfor- mation in a simple model, Ann. Phys.323, 1478 (2008)

View on Pith 2008
[32]

E. R. Anderson, S. K. Bogner, R. J. Furnstahl, and R. J. Perry, Operator evolution via the similarity renormaliza- tion group I: The deuteron, Phys. Rev. C82, 054001 (2010), arXiv:1008.1569 [nucl-th]

View on Pith Pith review arXiv 2010
[33]

S. Deser, M. L. Goldberger, K. Baumann, and W. Thirring, Energy level displacements in pi-mesonic atoms, Phys. Rev.96, 774 (1954)

View on Pith 1954
[34]

T. L. Trueman, Energy level shifts in atomic states of strongly-interacting particles, Nucl. Phys.26, 57 (1961)

View on Pith 1961
[35]

J. Carbonell, J.-M. Richard, and S. Wycech, On the relation between protonium level shifts and nucleon- antinucleon scattering amplitudes, Z. Phys. A343, 325 (1992). 6 APPENDIX: CONVERGENCE TESTS FOR OTHER OBSER V ABLES In this section, we provide our results for several useful observables for this system, including phase shifts, scat- tering length, and ...

View on Pith 1992

How the literature uses it

What this paper does with the arXiv papers it cites

Each citing sentence is taken from the citing paper's LaTeX source and typed by Pith's classifier. A label appears at probability 0.8 or more (0.95 for support), a contest at 0.7 or more; the quoted words are the citing authors'. How each label was checked · JSON

What it cites · 6 sentences without a confident label

Uses the method or tool of 7 papers

To study the $p̅$-$^4 He$ system, we describe the $^4 He$ target using the translationally invariant no-core shell model (NCSM) [ref] , and the $p̅$-$^4 He$ dynamics using the no-core shell model/resonating group method (NCSM/RGM) [ref] .

Few-nucleon systems in translationally invariant harmonic oscillator basis · Introduction · 1.00
To study the $p̅$-$^4 He$ system, we describe the $^4 He$ target using the translationally invariant no-core shell model (NCSM) [ref] , and the $p̅$-$^4 He$ dynamics using the no-core shell model/resonating group method (NCSM/RGM) [ref] .

Ab initio no-core shell model calculations for light nuclei · Introduction · 1.00
To study the $p̅$-$^4 He$ system, we describe the $^4 He$ target using the translationally invariant no-core shell model (NCSM) [ref] , and the $p̅$-$^4 He$ dynamics using the no-core shell model/resonating group method (NCSM/RGM) [ref] .

Ab Initio Many-Body Calculations of n-3H, n-4He, p-{3,4}He, and n-10Be Scattering · Introduction · 1.00

Compares with 1 paper

For direct comparison with the lighter targets studied in Ref. [ref] , we show the kernel at the same truncation, $N_max=20$.

Light antiproton-nucleus systems at low energies with the ab initio NCSM/RGM method · Introduction · 0.97

Cites as background 4 papers

Other choices for the $NN̅$ interaction are discussed in Ref. [ref] .

Comparison of $\bar{\hbox{N}}\hbox{N}$ optical models · Introduction · 0.90
The availability of low-energy antiproton beams at the CERN antiproton decelerator (CERN/AD), together with new experimental proposals at CERN [ref] , has renewed interest in the theoretical study of antiprotonic systems [ref] .

CERN AD/ELENA Antimatter Program · Introduction · 0.99
The availability of low-energy antiproton beams at the CERN antiproton decelerator (CERN/AD), together with new experimental proposals at CERN [ref] , has renewed interest in the theoretical study of antiprotonic systems [ref] .

2601.06541 · Introduction · 0.99

Discussion

Disagree with the review, or know something it missed? Leave a comment, highlight any passage above to comment on it, or challenge this review formally.

[1] [21]

J. Carbonell, G. Hupin, and S. Wycech, Comparison of ¯NNoptical models, Eur. Phys. J. A59, 259 (2023), arXiv:2309.14831 [nucl-th]

View on Pith Pith review arXiv 2023

[2] [1]

R. Caravitaet al., CERN AD/ELENA antimatter pro- gram (2025), arXiv:2503.22471 [nucl-ex]

View on Pith Pith review arXiv 2025

[3] [2]

P.-Y. Duerinck and R. Lazauskas,Ab initiodescription of ¯p+ 3H and ¯p+ 3He systems in optical models, Phys. Rev. C113, 054003 (2026), arXiv:2601.06541 [nucl-th]

View on Pith arXiv 2026

[4] [3]

P.-Y. Duerinck, R. Lazauskas, and J. Dohet-Eraly, Antiproton-deuteron hydrogenic states from a coupled- channel approach, Phys. Rev. C108, 054003 (2023)

View on Pith 2023

[5] [4]

M. Vorabbi, M. Gennari, P. Finelli, C. Giusti, and P. Navr´ atil, Elastic antiproton-nucleus scattering from chiral forces, Phys. Rev. Lett.124, 162501 (2020), arXiv:1906.11984 [nucl-th]

View on Pith Pith review arXiv 2020

[6] [5]

T. Aumannet al.(PUMA), PUMA, antiProton unstable matter annihilation, Eur. Phys. J. A58, 88 (2022)

View on Pith 2022

[7] [6]

A. Trzcinskaet al., Neutron density distributions de- duced from antiprotonic atoms, Phys. Rev. Lett.87, 082501 (2001)

View on Pith 2001

[8] [7]

P. Lubinskiet al., Composition of the nuclear periph- ery from antiproton absorption, Phys. Rev. C57, 2962 (1998), arXiv:nucl-ex/9808005

View on Pith Pith review arXiv 1998

[9] [8]

B. R. Barrett, P. Navr´ atil, and J. P. Vary,Ab initiono core shell model, Prog. Part. Nucl. Phys.69, 131 (2013)

View on Pith 2013

[10] [9]

P. Navr´ atil, G. P. Kamuntavicius, and B. R. Barrett, Few nucleon systems in translationally invariant har- monic oscillator basis, Phys. Rev. C61, 044001 (2000), arXiv:nucl-th/9907054

View on Pith Pith review arXiv 2000

[11] [10]

P. Navratil,Ab initiono-core shell model calculations for light nuclei, in169th Course of International School of Physics ‘Enrico Fermi’: Nuclear Structure far from Stability: New Physics and New Technology(IOS, Ams- terdam, 2007) pp. 147–183, arXiv:0711.2702 [nucl-th]

View on Pith Pith review arXiv 2007

[12] [11]

S. Quaglioni and P. Navr´ atil,Ab initiomany-body cal- culations ofn- 3H,n- 4He,p- 3,4He andn- 10Be scattering, Phys. Rev. Lett.101, 092501 (2008), arXiv:0804.1560 [nucl-th]

View on Pith Pith review arXiv 2008

[13] [12]

S. Quaglioni and P. Navr´ atil,Ab initiomany-body cal- culations of nucleon-nucleus scattering, Phys. Rev. C79, 044606 (2009), arXiv:0901.0950 [nucl-th]

View on Pith Pith review arXiv 2009

[14] [13]

P. Navr´ atil, S. Quaglioni, G. Hupin, C. Romero-Redondo, and A. Calci, Unifiedab initioapproaches to nuclear structure and reactions, Phys. Scripta91, 053002 (2016), arXiv:1601.03765 [nucl-th]

View on Pith Pith review arXiv 2016

[15] [14]

A. Dehghani, G. Hupin, S. Quaglioni, and P. Navr´ atil, Light antiproton-nucleus systems at low energies with theab initioNCSM/RGM method, Phys. Rev. C114, 014613 (2026), arXiv:2602.18162 [nucl-th]

View on Pith Pith review arXiv 2026

[16] [15]

P. Descouvemont and D. Baye, TheR-matrix theory, Rept. Prog. Phys.73, 036301 (2010), arXiv:1001.0678 [nucl-th]

View on Pith Pith review arXiv 2010

[17] [16]

M. Hesse, J. M. Sparenberg, F. Van Raemdonck, and D. Baye, Coupled-channelR-matrix method on a La- grange mesh, Nucl. Phys. A640, 37 (1998)

View on Pith 1998

[18] [17]

D. R. Entem and R. Machleidt, Accurate charge depen- dent nucleon nucleon potential at fourth order of chiral perturbation theory, Phys. Rev. C68, 041001 (2003), arXiv:nucl-th/0304018

View on Pith Pith review arXiv 2003

[19] [18]

M. Kohno and W. Weise, Proton-antiproton scattering and annihilation into two mesons, Nucl. Phys. A454, 429 (1986)

View on Pith 1986

[20] [19]

T. Ueda, Antinucleon-nucleon potentials for bound and scattering states, Prog. Theor. Phys.62, 1670 (1979)

View on Pith 1979

[21] [20]

J.-M. Richard, Antiproton physics, Front. in Phys.8, 6 (2020), arXiv:1912.07385 [nucl-th]

View on Pith Pith review arXiv 2020

[22] [22]

F. Balestraet al., Antiproton-helium annihilation around 44 MeV/c, Phys. Lett. B230, 36 (1989)

View on Pith 1989

[23] [23]

A. Zenoniet al., ¯pDand ¯p4He annihilation cross-sections at very low-energy, Phys. Lett. B461, 413 (1999)

View on Pith 1999

[24] [24]

F. Balestraet al., Antiproton- 4He interactions at 200 MeV/c, Phys. Lett. B305, 18 (1993)

View on Pith 1993

[25] [25]

C. J. Batty, E. Friedman, and A. Gal, Strong interac- tion physics from hadronic atoms, Phys. Rept.287, 385 (1997)

View on Pith 1997

[26] [26]

J. D. Davieset al., Measurement of strong interaction effects in antiprotonic helium atoms, Phys. Lett. B145, 319 (1984)

View on Pith 1984

[27] [27]

M. Schneideret al., X-rays from antiprotonic 3He and 4He, Z. Phys. A338, 217 (1991)

View on Pith 1991

[28] [28]

P. Navr´ atil, Translationally invariant density, Phys. Rev. C70, 014317 (2004)

View on Pith 2004

[29] [29]

A. Dehghani,Reactions with antiprotons in the theory of cold nuclear collisions, Ph.D. thesis, Paris-Saclay Univer- sity (2025), https://theses.hal.science/tel-05398592

View on Pith 2025

[30] [30]

S. K. Bogner, R. J. Furnstahl, and R. J. Perry, Similarity renormalization group for nucleon-nucleon interactions, Phys. Rev. C75, 061001 (2007)

View on Pith 2007

[31] [31]

S. Bogner, R. Furnstahl, and R. Perry, Three-body forces produced by a similarity renormalization group transfor- mation in a simple model, Ann. Phys.323, 1478 (2008)

View on Pith 2008

[32] [32]

E. R. Anderson, S. K. Bogner, R. J. Furnstahl, and R. J. Perry, Operator evolution via the similarity renormaliza- tion group I: The deuteron, Phys. Rev. C82, 054001 (2010), arXiv:1008.1569 [nucl-th]

View on Pith Pith review arXiv 2010

[33] [33]

S. Deser, M. L. Goldberger, K. Baumann, and W. Thirring, Energy level displacements in pi-mesonic atoms, Phys. Rev.96, 774 (1954)

View on Pith 1954

[34] [34]

T. L. Trueman, Energy level shifts in atomic states of strongly-interacting particles, Nucl. Phys.26, 57 (1961)

View on Pith 1961

[35] [35]

J. Carbonell, J.-M. Richard, and S. Wycech, On the relation between protonium level shifts and nucleon- antinucleon scattering amplitudes, Z. Phys. A343, 325 (1992). 6 APPENDIX: CONVERGENCE TESTS FOR OTHER OBSER V ABLES In this section, we provide our results for several useful observables for this system, including phase shifts, scat- tering length, and ...

View on Pith 1992