Publications

2026

• Holographic shear correlators at low temperatures, and quantum η/s
  
  • Kanargias Alexandros
  • Kiritsis Elias
  • Murthy Sameer
  • Papadoulaki Olga
  • Porfyriadis Achilleas
  Journal of High Energy Physics, Springer, 2026, 2026 (7), pp.149. The strongly-coupled 3-dimensional theory, holographically dual to black branes at fixed chemical potential μ and temperature T ≪ μ is considered in AdS 4 Einstein-Maxwell theory. The retarded Green’s functions at frequency ω is calculated using holography in the regime ω , T ≪ μ but otherwise arbitrary. When the transverse space has finite volume, there is a non-zero energy scale E gap , scaling as 1/ μ for large μ , below which quantum-gravitational corrections due to the fluctuations of the nearly-gapless Schwarzian modes become important. Such corrections to the retarded Green’s function are calculated at different relative values of ω , T , and E gap . The ω → 0 limit is used to define the shear viscosity η . As the temperature is lowered below μ , quantum corrections are found to increase the value of η with respect to its semiclassical value. The quantum-corrected result for η diverges as $$ \sqrt{{\mathrm{E}}_{\mathrm{gap}}/T} $$ E gap / T at T ≪ E gap , in accord with corresponding results for the absorption cross section. The quantum result for the ratio η / s , where s is the entropy density, dips below the semiclassical limit of 1/4 π when E gap ≪ T ≪ μ , then turns back to increase towards lower temperatures, and finally diverges at temperatures much below E gap . (10.1007/JHEP07(2026)149)
  DOI : 10.1007/JHEP07(2026)149
• Gluon radiation from a QCD antenna with realistic parton-medium interactions
  
  • Andrés Carlota
  • Apolinário Liliana
  • Armesto Néstor
  • Cordeiro André
  • Domínguez Fabio
  • Guerrero-Rodríguez Pablo
  • Milhano José Guilherme
  , 2026. The spectrum of coherent gluon radiation from a quark-antiquark pair undergoing multiple scatterings within a colored medium is central for understanding in-medium parton cascades. However, current efforts are constrained by reliance on a number of approximations, such as the harmonic oscillator approximation, that are only valid within limited regions of phase space. In this paper, we circumvent this problem by expressing the full in-medium gluon emission spectrum as a set of differential equations that can be solved numerically. This formalism, previously applied to the case of medium-induced radiation off a single color charge, allows to resum medium interactions to all orders while employing realistic scattering models. The resulting angle and energy distributions of emitted gluons serve to illustrate the breakdown of color coherence across the entire accessible phase-space, and constitute a definite step towards a higher-precision description of jet observables.
• Irrational CFTs from coupled anyon chains with non-invertible symmetries?
  
  • Antunes António
  • Rong Junchen
  SciPost Physics, SciPost Foundation, 2026, 21 (1), pp.005. Irrational CFTs in 1+1d with a discrete spectrum and no conserved currents other than the stress-tensor are expected to be generic, unsolvable by standard methods, and hard to construct explicitly. We introduce a lattice model that realizes a candidate for such a CFT as a conformal phase of matter without fine-tuning. The model is constructed by coupling $N\geq2$ golden anyon chains together, preserving $N$ copies of the Fibonacci non-invertible symmetry. We use the MPS/DMRG approach to study this model numerically, which allows us to calculate the corresponding conformal data, obtaining hints of its irrationality. As a byproduct of our analysis, we provide an extensive list of rational CFTs with $1 (10.21468/SciPostPhys.21.1.005)
  DOI : 10.21468/SciPostPhys.21.1.005
• Can every set of incompatible measurements lead to genuine multipartite steering?
  
  • Antunes Porto Lucas Emanuel
  • Tendick Lucas
  • Cavalcanti Daniel
  • Uola Roope
  • Quintino Marco Túlio
  , 2026. Measurement incompatibility and bipartite quantum steering are known to display a strong connection: a set of measurements is incompatible if and only if it can lead to bipartite steering. Despite such a close link between these concepts in bipartite scenarios, little is known in the multipartite setting, where notions of genuine multipartite correlations play major roles. In this work we prove that, as in the bipartite case, incompatibility is also necessary and sufficient for genuine multipartite steering in any multipartite scenario with a single uncharacterised party. Interestingly, genuine multipartite steering can be extracted from any set of incompatible measurements using states which are not SLOCC equivalent, such as GHZ and W states. In contrast, we prove that this result does not hold in scenarios with more than one uncharacterised party, by presenting a set of incompatible measurements that can never lead to genuine multipartite steering in these cases. In order to obtain our main results, we introduce methods tailored for multipartite correlations, paving the way to understanding the role of measurement incompatibility beyond bipartite scenarios. (10.48550/arXiv.2603.25345)
  DOI : 10.48550/arXiv.2603.25345
• Orbital magnetoresistance in the antiferromagnet CoO driven by dynamic orbital angular momentum
  
  • Schmitt Christin
  • Krishnia Sachin
  • Zeer Mahmoud
  • Galíndez-Ruales Edgar
  • Loyal Mehak
  • Köhler Jonas
  • Micus Luca
  • Kikkawa Takashi
  • Arisawa Hiroki
  • Denneulin Thibaud
  • Kovács András
  • Xu Renyou
  • Tran Duc
  • Kronast Florian
  • Go Dongwook
  • Pourovskii Leonid
  • Dunin-Borkowski Rafal
  • Kuschel Timo
  • Ležaić Marjana
  • Sinova Jairo
  • Saitoh Eiji
  • Jakob Gerhard
  • Gomonay Olena
  • Mokrousov Yuriy
  • Kläui Mathias
  Science, American Association for the Advancement of Science (AAAS), 2026, 393 (6806), pp.76-79. Recent predictions of orders of magnitude larger orbital current effects compared with spin currents have attracted considerable interest. However, orbital currents must first be converted into spin currents to interact with the static magnetization dominated by spin angular momentum in conventional magnets. By using a magnet dominated by orbital angular momentum (OAM), we demonstrate a 70-fold enhancement in orbital Hall magnetoresistance in cobalt II oxide/copper (CoO/Cu*), compared with spin Hall magnetoresistance in cobalt II oxide/platinum (CoO/Pt). This arises from interactions between dynamic OAM from surface-oxidized Cu* and static OAM in the antiferromagnetic insulator CoO. Our results show how by using OAM-dominated materials, we can harness the benefits of giant orbital currents that have not been possible using conventional spin-dominated magnets. (10.1126/science.adw1808)
  DOI : 10.1126/science.adw1808
• On the range of competing random walks
  
  • Baccara Maxence
  , 2026. We consider $N$ independent random walks $X^1,\dots,X^N$ in the lattice $\mathbb{Z}^d$ and prove limit theorems for the competitive range $\mathcal{R}_n^k$ of the $k$-th random walk $X^k$, which corresponds to the number of distinct sites that it has discovered before any of the other $X^\ell$, $\ell\ne k$, up to time $n$. This is a natural object to study foraging mechanisms in population ecology, in which context it is also natural to ask how the effect of competition for the access to resources affects the number of resources consumed by each individual. We work with random walks in the domain of attraction of a $\beta$-stable law and focus on the regime $d/\beta\in[1,3/2)$, in which classical results for the range show that the fluctuations are described by the renormalized self-intersection local time of the limiting process. We establish a central limit theorem in which a competition term emerges, thus answering the two previous questions we asked. We end the paper with a brief discussion on the remaining regimes $d/\beta\ge3/2$, in which the fluctuations are Gaussian and are not affected by the competition, and $d/\beta<1$ in which no strong law of large numbers holds and we expect the effect of the competition to strongly affect the first-order asymptotics.
• Threatening excursions in large population quasi-stationary birth and death systems. On a question of Antonio Galves.
  
  • Collet Pierre
  • Martínez Servet
  • Méléard Sylvie
  , 2026. We consider time continuous multispecies birth and death processes in a regime of large populations. The jump rates depend on a large scaling parameter K modeling the charge capacity. When K tends to infinity, the process is close (in finite time) to a dynamical system containing a non zero global attracting equilibrium and zero as unstable equilibrium. For each fixed K, extinction in finite time occurs almost surely and a quasi-stationary distribution occurs naturally in the study of the statistics over times scales which are large but smaller than the extinction time scale. Before this catastrophic event the process makes many unsuccessful large deviations attempts with time scales corresponding to how far it deviates from the quasi-equilibrium. The paper concerns the statistical description of these typical trajectories starting from the quasi-stationary distribution until extinction. An unusual mixing property yields large time scale behavior for the process starting from a fixed state. We give a precise statistical description of the successive exit times of the process rescaled by K from a neighborhood of the equilibrium of the dynamical system in a clumping time scale and prove their asymptotic Poisson distribution. We also give a precise description of the asymptotic distribution of the successive records until extinction.
• Next-to-next-to-leading order QCD corrections to pion (kaon)-induced exclusive Drell-Yan process
  
  • Jia Yu
  • Pire Bernard
  • Song Qin-Tao
  • Tang Guang
  • Wang Zhe-Yu
  , 2026. The high-energy pion and kaon beams proposed for future experiments at J-PARC offer a unique opportunity to measure exclusive Drell-Yan processes induced by pions or kaons—equivalently, inverse deeply virtual meson production with $M=\pi,K$. To facilitate precise comparisons between theory and future data, we calculate the next-to-next-to-leading order (NNLO) QCD corrections to $\pi^- p\to \gamma^*(\to l^+l^-) + n$ and $K^- p\to \gamma^*(\to l^+l^-) + \Lambda$. Our calculations are performed within the generalized parton distribution (GPD) factorization framework, accurate to the leading twist in the generalized Bjorken limit ($Q^2\gg |t|,\,\Lambda_{\rm QCD}^2$). We find that the NNLO QCD corrections are substantial and positive; incorporating them is therefore imperative for reliable theoretical predictions in confrontation with forthcoming experiments.
• Bubbling wormholes and matrix models
  
  • Betzios Panos
  • Lee Ji Hoon
  • Papadoulaki Olga
  • Zhou Yanjun
  Journal of High Energy Physics, Springer, 2026, 2026 (6), pp.224. A bstract The thermofield double state entangles two copies of a CFT via a sum over energy eigenstates and is dual to the two-sided eternal black hole. We explore an analogous construction using sums over gauge group representations of half-BPS Wilson loops in multiple copies of U ( N ) $$ \mathcal{N} $$ N = 4 super Yang-Mills. These sums act as delta function-like operators that correlate the eigenvalues of the corresponding half-BPS matrix models. We suggest that the holographic duals are “bubbling wormhole” geometries: multi-covers of AdS 5 × S 5 whose conformal boundary consists of multiple four-spheres intersecting on a common circle. We analyze the matrix model free energy, discuss its bulk interpretation, and study probe loops in these backgrounds. (10.1007/JHEP06(2026)224)
  DOI : 10.1007/JHEP06(2026)224
• Thermal One-point Functions and Asymptotic CFT Data: QFT in AdS
  
  • Burić Ilija
  • Mangialardi Francesco
  • Russo Francesco
  • Schomerus Volker
  • Vichi Alessandro
  , 2026. We investigate the thermal partition and one-point functions of the three-dimensional conformal field theory dual to a massive interacting scalar field in AdS$_4$. Using thermal inversion formulas, we determine the asymptotic behaviour of the spectral density and OPE coefficients involving heavy operators at fixed spin. We first analyse these CFT data for the generalised free field, corresponding to the non-interacting bulk theory. Then we compute the first-order perturbative corrections induced by the cubic and quartic bulk interactions. The thermal observables considered here probe a sector associated with operators of large dimension and, in the bulk description, a regime dominated by states with large particle number. This regime remains comparatively unexplored even in generalised free field theory. Remarkably, the asymptotic formulas obtained from thermal inversion remain quantitatively accurate far from the asymptotic regime, describing CFT data reliably already at intermediate conformal weights. Our results show that this feature survives the inclusion of bulk interactions and provide new analytic control over heavy-state data in conformal field theories.
• An analytical framework to unify ecological and engineering resilience near critical transitions
  
  • Gamot Tristan
  • van Dooren Tom
  , 2026. The capacity of dynamical systems to resist and recover from perturbations, broadly referred to as resilience, is commonly expressed by two complementary quantities: ecological and engineering resilience. As many complex systems exhibit critical transitions, or tipping points, understanding how these resiliences jointly change nearby them is central to characterising and anticipating such shifts. Here, we develop a theoretical framework that clarifies this for bifurcation-induced tipping, i.e., critical transitions triggered by the crossing of a local bifurcation. Using normal form theory, we derive explicit scaling laws for commonly used resilience metrics as functions of the distance to the bifurcation point in parameter space, and show that these extend to general models up to a scaling factor. They are particularly relevant for detecting tipping, where the relative behaviour of metrics matters more than their absolute values. The rates at which metrics decrease as the bifurcation is approached depend on both the type of bifurcation and the metric considered. Furthermore, our results show that, sufficiently close to a local bifurcation, resiliences are intrinsically linked. Our predictions, which replace previously proposed scalings based on heuristic arguments, are validated for three representative models covering all commonly encountered local bifurcations in one-dimensional systems.
• A menagerie of wormholes and cosmologies in the gravitational path integral
  
  • Betzios Panos
  • Ghiringhelli Paul
  • Gialamas Ioannis
  • Papadoulaki Olga
  Journal of High Energy Physics, Springer, 2026, 2026 (6), pp.171. A bstract We analyse a variety of Euclidean saddles in the gravitational path integral, with asymptotic AdS boundary conditions, in a class of Einstein-Scalar-Maxwell models. These include single boundary solutions, usual and wineglass wormholes, as well as more exotic (quasi)-oscillatory saddles. Our construction shows how an unbound number of oscillations gets tamed, when flat directions of the potential get lifted. We find several interesting phase transitions between these solutions. The Euclidean wormhole backgrounds can be analytically continued to Lorentzian FLRW universes. Some of them contain an early period of inflation. We delineate the conditions under which they can be the dominant saddles in the gravitational path integral and use them to estimate ratios of probabilities for different cosmological outcomes. (10.1007/JHEP06(2026)171)
  DOI : 10.1007/JHEP06(2026)171
• Azimuthal decorrelation in diffractive dijet production
  
  • Shao Ding Yu
  • Shi Yu
  • Zhang Cheng
  • Zhou Jian
  • Zhou Ya-Jin
  , 2026. We calculate the azimuthal angular decorrelation of diffractive dijets in ultra-peripheral heavy-ion, $ep$, and $eA$ collisions to probe non-perturbative diffractive transverse momentum-dependent distributions. Focusing on the dominant semi-inclusive channel with an unobserved semi-hard gluon, we perform an all-order resummation of soft gluon emissions for the transverse energy-energy correlator observable, accounting for both initial and final state radiation. We also analyze heavy-quark pair production and demonstrate the sensitivity of the decorrelation to the jet axis definition. Finally, we provide numerical predictions for relevant kinematics at LHC UPCs, HERA, and the future EIC. Our results demonstrate that the acoplanarity of diffractive dijet production could serve as a promising probe of diffractive transverse momentum-dependent distributions.
• Quark orbital angular momentum as a chiral magnetic effect
  
  • Kim June-Young
  • Won Ho-Yeon
  • Weiss Christian
  , 2026. The flavor-nonsinglet ($u - d$) quark angular momentum (AM) in the proton is computed based on the effective spin-flavor dynamics emerging from chiral symmetry breaking by QCD instantons. The QCD AM operators are converted to effective spin-flavor operators expressing instanton-induced chiral interactions. A large negative orbital AM $L_{u - d}$ arises as a ``chiral magnetic effect'' of the interaction of the quarks with the chiral mean field in the proton in the large-$N_c$ limit. It cancels part of the large positive spin AM $S_{u-d}$ and reduces the total AM $J_{u-d} = L_{u-d} + S_{u-d}$, in agreement with lattice QCD calculations.
• A new Ising/tricritical-Ising interface: From ${W}_3$ symmetry to Rydberg atoms
  
  • Antunes António
  • Rong Junchen
  , 2026. We consider interfaces between critical spin-chains in different universality classes, described in the continuum limit by defect/interface conformal field theory (DCFT/ICFT). We find a new conformal interface between the Tricritical Ising (TIM) and the Ising CFT. We also explore the possibility of its experimental realizations in the context of Rydberg atom arrays. Our analysis emphasizes non-invertible symmetries and consistency under modular transformations, and uses defect couplings and the defect spectrum -- including in the case of mixed boundary conditions -- to make sharp experimental predictions. The structure of the observables hinges on a newly discovered pattern of emergent ${W}_3$ chiral symmetry for the Tricritical-Ising/Ising interface.
• Comparing Symmetrized Determinant Neural Quantum States for the Hubbard Model
  
  • Sharma Louis
  • Shokry Ahmedeo
  • Nutakki Rajah
  • Simard Olivier
  • Ferrero Michel
  • Vicentini Filippo
  Physical Review B, American Physical Society, 2026, 113 (24), pp.245104. Accurate simulations of the Hubbard model are crucial to understanding strongly correlated phenomena, where small energy differences between competing orders demand high numerical precision. In this work, Neural Quantum States are used to probe the strongly coupled and underdoped regime of the square-lattice Hubbard model. We systematically compare the Hidden Fermion Determinant State and the Jastrow-Backflow ansatz, parametrized by a Vision Transformer, finding that in practice, their accuracy is similar. We also test different symmetrization strategies, finding that output averaging yields the lowest energies, though it becomes costly for larger system sizes. On cylindrical systems, we consistently observe filled stripes. On the torus, our calculations display features consistent with a doped Mott insulator, including antiferromagnetic correlations and suppressed density fluctuations. Our results demonstrate both the promise and current challenges of neural quantum states for correlated fermions. (10.1103/s3kd-bc4q)
  DOI : 10.1103/s3kd-bc4q
• Kinetic Theory of Carroll Hydrodynamics
  
  • Chabirand Victor
  • Fiorucci Adrien
  • Petropoulos P. Marios
  • Vilatte Matthieu
  , 2026. We develop the foundations of Carrollian statistical mechanics by considering a system of interacting instantonic space-filling branes on a flat background, thereby providing the closest Carrollian analogue to the Galilean gas of interacting particles that underpins Boltzmann's collision theory. By adapting Boltzmann's statistical approach within this framework, we provide a first-principles microscopic derivation of the so-called Carrollian fluid equations, which were previously obtained as the vanishing-speed-of-light limit of relativistic conservation laws. We then use this analysis as a basis for formulating the first elements of Carrollian thermodynamics.
• Calculating extremely high energy bremsstrahlung in matter
  
  • Arnold Peter
  • Bautista Joshua
  • Elgedawy Omar
  • Iqbal Shahin
  , 2026. Ultra-relativistic electrons initiate electromagnetic showers in ordinary matter that evolve through bremsstrahlung and pair production. At very high energy, the quantum mechanical duration of bremsstrahlung becomes longer than the mean free time to elastically scatter from the medium, leading to a significant suppression known at the Landau-Pomeranchuk-Migdal (LPM) effect. For some ranges of bremsstrahlung photon and initial electron energies $(k_γ,E)$, the duration becomes so long that it will also overlap with subsequent pair production by the bremsstrahlung photon, disrupting LPM suppression and drastically changing LPM predictions. We have previously calculated this change for extremely high energies ($k_γ\gg 2$ TeV or more, depending on the medium), for which the electron mass and medium-induced photon mass could be ignored. In this paper, we extend that analysis to lower (but still ultra-relativistic) energy by accounting for those masses, leading to a rich map of behavior in different regions of $(k_γ,E)$.
• Probing Saturation Effect in Heavy Meson Pair Correlation in Forward $pA$ Collisions
  
  • Gao Zhan
  • Marquet Cyrille
  • Shi Yu
  • Xiao Bo-Wen
  , 2026. Forward two-particle angular correlations in $pA$ collisions have long been recognized as a particularly sensitive observable for exploring gluon saturation effects. In the back-to-back regime, two-particle correlations receive substantial contributions from both soft-gluon radiation and saturation effects. In this work, we study heavy meson pair correlation in forward proton-nucleus collisions by incorporating a unified Sudakov resummation for heavy meson pair correlations in the Color Glass Condensate effect theory. Our results are in good agreement with the $Δϕ$ data measured by the LHCb Collaboration for $D^0 \bar D^0$ pairs in forward $pp$ and $pA$ collisions, as well as $J/ψ$ pairs from $b\bar b$ decays in forward $pp$ collisions. Furthermore, we present predictions for $D\bar D$ and $B\bar B$ correlations in the forward rapidity regions at the Large Hadron Collider. A pronounced mass-hierarchy is observed in the nuclear modification factor, $R_{pA}\big|_{m_b}<R_{pA}\big|_{m_c}$, indicating stronger sensitivity to saturation effects at small $x$. As the rapidity increases, the suppression becomes more pronounced while the mass hierarchy remains robust. This study will help us to search for the saturation signal via heavy-meson pair correlations in forward $pA$ collisions.
• Cutting rules in strong field QED with application to trident pair production
  
  • Selivanov Y.V
  • Mironov A.A
  • Alexeenko A.I
  • Fedotov A.M
  , 2026. Following Veltman's approach, we formulate and discuss a general cutting equation for QED in a plane-wave background. We apply the corresponding cutting rules to justify the connection between the two-loop radiative corrections to elastic electron scattering and the rate of the trident process in a constant crossed field. As a byproduct, we compare the previously published results for the trident process in a constant crossed field and present a complete analytical expression for direct and exchange contributions to its rate, which is resolved in the spin of the initial electron. Our findings establish that although total rates can be reliably extracted from higher-loop by applying the cutting rules, reconstruction of differential rates requires additional care. The cutting rules apply to any loop order and may be extended to nonperturbative regimes.
• Remote air photonics based on high-repetition-rate Yb:YAG laser filamentation
  
  • Fu Silin
  • Mahieu Benoit
  • Lozano Magali
  • Bizet Laurent
  • Alahyane Fatima
  • Mysyrowicz André
  • Couairon Arnaud
  • Houard Aurélien
  Optics Letters, Optical Society of America - OSA Publishing, 2026, 51 (10), pp.2880. Many atmospheric laser applications rely on the long-range propagation of laser pulses. In this work, we demonstrate a method for remotely shaping laser beams by generating stable gaseous optical elements in air. These structures emerge from controlled gas dynamics driven by filamentation of a kilohertz picosecond Yb:YAG laser. We observe a new, to the best of our knowledge, air photonic structure—a tunable defocusing lens—attributed to the cumulative effects of low-density channels. Additionally, we show that self-focusing of a collimated Laguerre–Gauss beam can form a permanent air waveguide of 6 mm extending over more than 20 meters. Numerical simulations of the gas dynamics reproduce the observed features of a continuous wave (CW) probe beam injected into these optical structures. This air photonics strategy has broad potential applications in laser power modulation and atmospheric optics. (10.1364/OL.595527)
  DOI : 10.1364/OL.595527
• 5<i>d</i>-mediated indirect exchange and effective spin Hamiltonians in Ce triangular-lattice delafossites
  
  • Pourovskii Leonid
  Physical Review B, American Physical Society, 2026, 113 (20), pp.L201109. Anisotropic intersite exchange interactions in frustrated rare-earth magnets are difficult to assess both theoretically and experimentally. Here, we propose an ab initio force-theorem framework combining the quasi-atomic Hubbard-I approach to 4$f$ correlations with a static mean-field treatment of the on-site intershell Coulomb interaction between rare-earth 4f and 5d states to simultaneously capture both 4$f$ superexchange and 5d-mediated indirect exchange. Applying it to the triangular lattice Ce delafossites CsCeSe₂, KCeS₂, and RbCeO₂, we find that the indirect exchange dominates in the selenide, the superexchange in the oxide, while both mechanisms contribute almost equally in the sulfide. The magnetic exciation spectra of CsCeSe₂ and KCeS₂ evaluated from the calculated spin Hamiltonains are in good qualitative and quantitative agreement with experimental data. (10.1103/mxcs-9dd7)
  DOI : 10.1103/mxcs-9dd7
• Scheme Transformations in Non-Linear QCD Evolution: Towards a Stable NLO BK Equation
  
  • Boussarie Renaud
  • Caucal Paul
  • Korcyl Piotr
  • Mehtar-Tani Yacine
  , 2026. High-energy QCD evolution at NLO suffers from large collinear logarithms that make the perturbative expansion of the Balitsky-Kovchegov (BK) equation unstable. We develop a systematic scheme-transformation framework using the Doi-Peliti formalism to relate projectile ($k^+$) and target ($k^-$) factorization schemes. The transformation of high-energy operators and the evolution kernel generates NLO terms that cancel the problematic double collinear logarithm. The resulting NLO BK equation is free of this instability, with only single collinear and double anti-collinear enhancements remaining. Numerical solutions show stable evolution up to $Y=10$ for both Golec-Biernat-Wusthoff and McLerran-Venugopalan initial conditions, providing a consistent path toward combining stable NLO evolution with rotated NLO impact factors.
• Revealing chiral-odd two-meson generalized distribution amplitudes in $e^- e^+ \to (\pi \pi) (\pi \pi)$ reactions
  
  • Bhattacharya Shohini
  • Boussarie Renaud
  • Pire Bernard
  • Szymanowski Lech
  Physical Review D, American Physical Society, 2026, 113, pp.094008. We demonstrate that chiral-odd dimeson generalized distribution amplitudes (CO-GDAs)—nonperturbative objects encoding the transition of a quark–antiquark pair into two mesons—can be accessed in high-energy e^- e^+ annihilation into two meson pairs, each with a relatively low invariant mass. While chiral-even GDAs contribute to the leading one-photon amplitude, the chiral-odd sector enters via two-photon exchange. We show that the interference between these amplitudes leads to measurable effects at BES III or future tau-charm factories. This work opens a direct path to experimentally probing the long-missing chiral-odd sector of meson structure—specifically, the anomalous tensorial magnetic moment of spin-zero mesons such as the pion. (10.1103/rl5q-5h2n)
  DOI : 10.1103/rl5q-5h2n
• Extremely high-energy bremsstrahlung in matter
  
  • Arnold Peter
  • Bautista Joshua
  • Elgedawy Omar
  • Iqbal Shahin
  , 2026. The theory of bremsstrahlung $e \to eγ$ by extremely high energy electrons passing through ordinary matter has been qualitatively incomplete. We revisit the suppression of bremsstrahlung by the Landau-Pomeranchuk-Migdal (LPM) effect, here accounting for quantum disruption of that effect from pair production. Our analysis covers the full range of ultra-relativistic electron and photon energies (subject to a few simplifying approximations).