Using <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mrow><mo>(</mo><mn>10087</mn><mo>±</mo><mn>44</mn><mo>)</mo></mrow><mo>×</mo><msup><mn>10</mn><mn>6</mn></msup><mi>J</mi><mo>/</mo><mi>ψ</mi></mrow></math> events collected with the BESIII detector operating at the BEPCII storage ring in 2009, 2012, 2018, and 2019, we perform a search for the reaction <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><mi>n</mi><mo>→</mo><mi mathvariant="normal">Λ</mi><mi mathvariant="normal">Λ</mi><mi>X</mi></mrow></math>, where <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>X</mi></math> denotes any additional final particles. Given the highly suppressed phase space for producing extra pions, the <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>X</mi></math> consists of either nothing or a photon, corresponding to the processes <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><mi>n</mi><mo>→</mo><mi mathvariant="normal">Λ</mi><mi mathvariant="normal">Λ</mi></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><mi>n</mi><mo>→</mo><mi mathvariant="normal">Λ</mi><msup><mi mathvariant="normal">Σ</mi><mn>0</mn></msup><mo>→</mo><mi mathvariant="normal">Λ</mi><mi mathvariant="normal">Λ</mi><mi>γ</mi></mrow></math>. The <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup></math> comes from the decay of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi>J</mi><mo>/</mo><mi>ψ</mi><mo>→</mo><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><msup><mover accent="true"><mi mathvariant="normal">Ξ</mi><mo>¯</mo></mover><mn>0</mn></msup></mrow></math>, while the neutron originates from material of the beam pipe. A signal is observed for the first time with a statistical significance of <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>6.4</mn><mi>σ</mi></mrow></math>. The cross section for the reaction <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><mo>+</mo><mmultiscripts><mi>Be</mi><mprescripts></mprescripts><none></none><mn>9</mn></mmultiscripts><mo>→</mo><mi mathvariant="normal">Λ</mi><mo>+</mo><mi mathvariant="normal">Λ</mi><mo>+</mo><mi>X</mi></mrow></math> is measured to be <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mo>(</mo><mn>43.6</mn><mo>±</mo><mn>10</mn><mo>.</mo><msub><mn>5</mn><mtext>stat</mtext></msub><mo>±</mo><mn>11</mn><mo>.</mo><msub><mn>1</mn><mtext>syst</mtext></msub><mo>)</mo><mspace width="0.28em"></mspace><mi>mb</mi></mrow></math> at <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msub><mi>P</mi><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup></msub><mo>≈</mo><mn>0.818</mn><mspace width="0.28em"></mspace><mi>GeV</mi><mo>/</mo><mi>c</mi></mrow></math>, where the first uncertainty is statistical and the second systematic. No significant <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>H</mi></math>-dibaryon signal is observed in the <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mi mathvariant="normal">Λ</mi><mi mathvariant="normal">Λ</mi></mrow></math> final state.

China

M. Ablikim

Russia

M.N. Achasov

Sweden

P. Adlarson

X.C. Ai

Germany

R. Aliberti

Italy

A. Amoroso

Q. An

Y. Bai

JINR

O. Bakina

Y. Ban

H.R. Bao

Poland

V. Batozskaya

Mongolia

K. Begzsuren

N. Berger

M. Berlowski

M. Bertani

D. Bettoni

F. Bianchi

E. Bianco

A. Bortone

I. Boyko

United States

R.A. Briere

A. Brueggemann

H. Cai

M.H. Cai

X. Cai

A. Calcaterra

G.F. Cao

N. Cao

Türkiye

S.A. Cetin

X.Y. Chai

J.F. Chang

G.R. Che

Y.Z. Che

C.H. Chen

 Chao Chen

G. Chen

H.S. Chen

H.Y. Chen

M.L. Chen

S.J. Chen

S.L. Chen

S.M. Chen

T. Chen

X.R. Chen

X.T. Chen

X.Y. Chen

Y.B. Chen

Y.Q. Chen

Z. Chen

Z.J. Chen

Z.K. Chen

J.C. Cheng

South Korea

S.K. Choi

X. Chu

G. Cibinetto

F. Cossio

United Kingdom

J. Cottee-Meldrum

J.J. Cui

H.L. Dai

J.P. Dai

A. Dbeyssi

R.E. de Boer

D. Dedovich

C.Q. Deng

Z.Y. Deng

A. Denig

I. Denysenko

M. Destefanis

F. De Mori

B. Ding

X.X. Ding

Y. Ding

Y.X. Ding

J. Dong

L.Y. Dong

M.Y. Dong

X. Dong

M.C. Du

S.X. Du

Y.Y. Duan

Z.H. Duan

P. Egorov

G.F. Fan

J.J. Fan

Y.H. Fan

J. Fang

S.S. Fang

W.X. Fang

Y.Q. Fang

L. Fava

F. Feldbauer

G. Felici

C.Q. Feng

J.H. Feng

L. Feng

Q.X. Feng

Experimental study of the reaction <math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup><mi>n</mi><mo>→</mo><mi mathvariant="normal">Λ</mi><mi mathvariant="normal">Λ</mi><mi>X</mi></mrow></math> using <math xmlns="http://www.w3.org/1998/Math/MathML"><msup><mi mathvariant="normal">Ξ</mi><mn>0</mn></msup></math>-nucleus scattering

We define a higher-derivative generalization of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">N</mi><mo>=</mo><mn>1</mn></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">N</mi><mo>=</mo><mn>2</mn></math> supersymmetric Maxwell-Chern-Simons theories. In particular, the chosen higher-derivative operator is a polynomial function of the d’Alembertian of arbitrary degree, and it is introduced exclusively in the gauge sector. The main goal is to explicitly compute the one-loop quantum corrections to the superfield effective potential for these theories. This is carried out by means of background field quantization in a higher-derivative <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>R</mi><mi>ξ</mi></msub></math> gauge. The effective potential is obtained in closed form and expressed in terms of the roots of polynomial functions.

Brazil

F.S. Gama

Higher-derivative <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">N</mi><mo>=</mo><mn>1</mn></mrow></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">N</mi><mo>=</mo><mn>2</mn></math> supersymmetric Maxwell-Chern-Simons theories at one loop in superspace

The rare decays mediated by flavor-changing neutral current processes, such as <math altimg='si108.svg'><mrow><mi>b</mi><mo>&#8594;</mo><mi>s</mi><msup><mi>&#8467;</mi><mo>+</mo></msup><msup><mi>&#8467;</mi><mo>&#8722;</mo></msup></mrow></math>, provide powerful probes of the Standard Model and potential windows into new physics. Particularly, the angular observables in these exclusive decays are valuable because of their sensitivity to short-distance dynamics and their reduced dependence on hadronic uncertainties, which mainly arise from form factors. In this work, we analyze the <math altimg='si107.svg'><mrow><msub><mstyle mathvariant='normal'><mi>&#923;</mi></mstyle><mi>b</mi></msub><mo>&#8594;</mo><mstyle mathvariant='normal'><mi>&#923;</mi></mstyle><mrow><mo>(</mo><mo>&#8594;</mo><mi>N</mi><mi>&#960;</mi><mo>)</mo></mrow><msup><mi>&#8467;</mi><mo>+</mo></msup><msup><mi>&#8467;</mi><mo>&#8722;</mo></msup></mrow></math> (with <math altimg='si109.svg'><mrow><mi>N</mi><mi>&#960;</mi><mo linebreak='goodbreak'>=</mo><mo>{</mo><mi>p</mi><msup><mi>&#960;</mi><mo>&#8722;</mo></msup><mo>,</mo><mi>n</mi><msup><mi>&#960;</mi><mn>0</mn></msup><mo>}</mo></mrow></math>) decay with polarized final-state lepton and derive the corresponding four-fold differential decay distributions. For the longitudinal, normal, and transverse polarization states, we systematically identify the additional angular coefficients that emerge relative to the unpolarized case. We find that the longitudinal polarization preserves the structure of the unpolarized distribution, while the normal and transverse polarizations introduce some new additional angular coefficients. The analytical expressions of all polarized and unpolarized angular coefficients are explicitly derived in terms of the helicity and transversity amplitudes. To compare the variation in the polarized and unpolarized angular observables, we have plotted them against the square of the momentum transfer <italic>q</italic> 2. Additionally, the Standard Model predictions of the polarization asymmetry observables are provided and their sensitivity to new physics is explored under different new physics scenarios. The obtained results, in the current study, for longitudinal and transverse polarization cases, provide a baseline for the lepton polarization dependent observables, which may serve as sensitive probes to test the Standard Model in these decays.

Pakistan

Rana Khan

Faisal Munir Bhutta

Ishtiaq Ahmed

M. Jamil Aslam

Lepton polarization dependent angular observables and the polarization asymmetries in the four-fold <math altimg='si107.svg'><mrow><msub><mstyle mathvariant='normal'><mi>&#923;</mi></mstyle><mi>b</mi></msub><mo>&#8594;</mo><mstyle mathvariant='normal'><mi>&#923;</mi></mstyle><mrow><mo>(</mo><mo>&#8594;</mo><mi>N</mi><mi>&#960;</mi><mo>)</mo></mrow><msup><mi>&#8467;</mi><mo>+</mo></msup><msup><mi>&#8467;</mi><mo>&#8722;</mo></msup></mrow></math> decay

In this work, the electromagnetic and gravitational form factors of $$\Delta $$ isobars, as well as the electromagnetic $$N-\Delta $$ transition form factors, are studied systematically and continuously using a covariant quark–diquark approach with the pion cloud effect. In our model, the baryon is treated as a two-body system to simplify calculations, and the quarks are assumed to be surrounded by the pion cloud. The related physical properties, such as the charge radius and magnetic moment of $$\Delta (1232)$$ and the helicity amplitudes of the $$N-\Delta $$ transition, are obtained and discussed. Our results for the form factors of both $$\Delta (1232)$$ and the electromagnetic $$N-\Delta $$ transition are in reasonable agreement with the experimental and lattice results. Moreover, we found that the pion cloud plays an important role in the results by increasing the magnetic transition form factor $$G_M(t)$$ and shifting the sign of the D-term of $$\Delta $$ to negative.

Jiaqi Wang

Dongyan Fu

Yubing Dong

Form factors of $$\Delta (1232)$$ and the electromagnetic $$N-\Delta $$ transition

We calculate the resummed perturbative free energy of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">N</mi><mo>=</mo><mn>4</mn></math> supersymmetric Yang-Mills in four spacetime dimensions (<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>SYM</mi></mrow><mrow><mn>44</mn></mrow></msub></mrow></math>) to order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>λ</mi><mrow><mn>5</mn><mo>/</mo><mn>2</mn></mrow></msup></math> in the ‘t Hooft coupling at finite temperature and zero chemical potential. All infrared divergences cancel when we include contributions from <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>SYM</mi></mrow><mrow><mn>44</mn></mrow></msub></mrow></math> ring diagrams and the final result is both ultraviolet and infrared finite. Our result has special significance since order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>λ</mi><mrow><mn>5</mn><mo>/</mo><mn>2</mn></mrow></msup></math> is the highest order calculation that can be done with perturbation theory, because there are nonperturbative effects associated with the magnetic mass scale that come into play at order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>λ</mi><mn>3</mn></msup></math>. We compare results obtained with regularization by dimensional reduction (RDR), which preserves supersymmetry, and canonical dimensional regularization (DR). We also compare with a generalized Padé approximant constructed by matching the weak coupling result at order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>λ</mi><mn>2</mn></msup></math> and the large <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>c</mi></msub></math> strong coupling result at order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>λ</mi><mrow><mo>−</mo><mn>3</mn><mo>/</mo><mn>2</mn></mrow></msup></math>. Finally we make a comparison between our result and the QCD free energy and show that <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>SYM</mi></mrow><mrow><mn>44</mn></mrow></msub></mrow></math> has better convergence properties.

Canada

Margaret E. Carrington

Gabor Kunstatter

Saudi Arabia

Ubaid Tantary

<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mi mathvariant="script">N</mi><mo>=</mo><mn>4</mn></mrow></math> supersymmetric Yang-Mills thermodynamics to order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>λ</mi><mrow><mn>5</mn><mo>/</mo><mn>2</mn></mrow></msup></math>

We study Dirac fields on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>AdS</mi></mrow><mrow><mi>n</mi></mrow></msub></mrow></math> in both global and Poincaré charts and, for each mass window, we classify the boundary conditions at conformal infinity that ensure the existence of advanced and retarded propagators. We distinguish the well-known MIT–bag class from a generalized family, thereby extending to arbitrary dimensions the procedure initiated in [D. S. Blanco, <a href="http://dx.doi.org/10.1063/5.0135971">J. Math. Phys. (N.Y.) 64, 032301 (2023)</a>.]. As in the scalar case, we show that suitable generalized boundary data can support bound states. In four dimensions, we work out two explicit examples: (i) the MIT case, for which we construct the advanced/retarded propagators and the two-point function of the associated ground state and (ii) a representative generalized boundary condition, for which we construct the propagators and exhibit a normalizable bound state.

Claudio Dappiaggi

Andrea Parpinel

Boundary conditions and Dirac fields on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msub><mrow><mi>AdS</mi></mrow><mrow><mi>n</mi></mrow></msub></mrow></math>

Using the Bogoliubov-Parasiuk theorem we derive differential equations for the sum of leading UV divergences of the Kähler potential in the general <math altimg='si5.svg'><mrow><mi mathvariant='script'>N</mi><mo linebreak='goodbreak'>=</mo><mn>1</mn></mrow></math> supersymmetric chiral theory. The obtained equations recover the limit of the renormalizable Wess-Zumino theory and also allow one to consider non-renormalizable chiral interactions. Some implications of the obtained equations are shown.

R.M. Iakhibbaev

A.I. Mukhaeva

Belarus

D.M. Tolkachev

Leading UV divergences of quantum corrections to Kähler superpotential in general <math altimg='si5.svg'><mrow><mi mathvariant='script'>N</mi><mo linebreak='goodbreak'>=</mo><mn>1</mn></mrow></math> chiral model

We investigate multipartite total amount of correlations by analyzing the mutual information of N-partite states for both free bosonic and fermionic fields in the background of a Garfinkle-Horowitz-Strominger (GHS) dilaton black hole. Focusing on multipartite GHZ and W states, we examine how the Hawking effect influences the N-partite mutual information when one observer hovers near the event horizon while the remaining observers stay in the asymptotically flat region. By tracing over the inaccessible modes inside the event horizon, we derive analytical expressions for the N-partite mutual information in dilaton spacetime for both bosonic and fermionic fields. Our results show that fermionic mutual information is larger than its bosonic counterpart under the influence of the dilaton black hole, whereas the fermionic relative entropy of coherence (REC) is smaller than the bosonic REC. Moreover, the mutual information of GHZ states is consistently larger than that of W states, while the REC of GHZ states is smaller than that of W states in curved spacetime. These findings reveal distinct behaviors of multipartite mutual information and quantum coherence for different particle statistics and multipartite state structures under gravitational effects, providing further insight into many-body total correlations in curved spacetime.

Xiao-Wei Teng

Rui-Yang Xu

Hui-Chen Yang

Shu-Min Wu

Bosonic and fermionic mutual information of N-partite systems in dilaton black hole background

We study two-body scattering as an SU(N)-equivariant map acting on tensor-product representation spaces and analyze the entanglement generated by the $\textit{S}$-matrix. This representation-theoretic perspective separates group structure from dynamics: the decomposition of $\textit{R}$⊗$\textit{R}$′ fixes the invariant operator algebra and therefore the qualitative entangling power of the process. For particles in the fundamental representation, End ($\textit{N}$⊗$\textit{N}$) = Span{𝕀, 𝕊}, so only the identity and swap directions preserve separability, whereas generic combinations generate entanglement. Adjoint-adjoint scattering involves a larger invariant algebra involving $\textit{d}$-tensors and is intrinsically entangling. In Yang-Mills theory one can use color-kinematics duality to show that the color kernel lies on a fixed ray of this operator space, yielding a universal maximum of the outgoing entanglement for scattering at right angles, $$ {E}_{\star}^{(2)}=\frac{3}{4} $$ for SU(2) and $$ {E}_{\star}^{(3)}\simeq 0.91 $$ , independent of kinematics. Dimension-six operators preserve this universality, while dimension-eight deformations populate new color sectors and shift $$ {E}_{\star}^{(N)} $$ , suggesting that entanglement in color space functions as a tomographic probe of effective operators. In helicity space, requiring maximally entangled inputs to scatter into maximally entangled outputs uniquely selects the Yang-Mills quartic coupling and enforces the color Jacobi identity, restating the on-shell Ward constraints as conditions on entanglement preservation. Our results suggest that the information-theoretic viewpoint unifies algebraic, geometric, and dynamical aspects of scattering.

Kun-Feng Lyu

Rahul Muraleedharan

Kuver Sinha

Entanglement, Yang-Mills, and the scattering matrix as an SU(N)-equivariant kernel

Recently, a semi-microscopic structure model has been presented to study the structure of a weakly-bound, two-body nucleus with a deformed core, including Pauli-blocking effects. The model has been successfully applied within the adiabatic distorted wave approximation (ADWA) reaction framework to study the reactions 16C(d, p) 17C, restricting the analysis to bound states of the residual 17C nucleus. In these calculations, the structure of 17C is described using the recently presented semimicroscopic Nilsson+AMD model (NAMD), considering different Pauli-blocking methods. In the present work, the analysis is extended to unbound states of this nucleus with the aim of constraining the location of the 1 <italic>d</italic> <inf>3/2</inf> single-particle strength and infer the <math altimg='si3.svg'><mrow><mi>N</mi><mo linebreak='goodbreak'>=</mo><mn>16</mn></mrow></math> shell-gap. Comparing the measured energy differential cross section for this reaction with calculations in which the position of the 1 <italic>d</italic> <inf>3/2</inf> orbital is arbitrarily varied, we conclude that a large shell-gap (&#8239;&gt;&#8239;5 MeV) is required, in agreement with recently reported value from [J. Lois-Fuentes et al., Phys. Lett. B 867, 139600 (2025)].

Spain

P. Punta

J.A. Lay

A.M. Moro

J. Lois-Fuentes

B. Fernández-Domínguez

Constraining the N=16 shell gap in 17C via transfer to the continuum in the 16C( <italic>d, p</italic>) 17C reaction