Using the Comisso-Asenjo magnetic reconnection mechanism, we study energy extraction from the Teo traversable rotating wormhole at different orbital locations. This wormhole has no event horizon and cannot reduce to a Kerr black hole in any parameter limit. We compute circular orbits on the equatorial plane, the prograde photon sphere, and the innermost stable circular orbit (ISCO). We find that below a certain spin, no circular orbit exists inside the ergosphere. Both the efficiency and power calculated from magnetic reconnection increase monotonically with angular momentum. Compared with a Kerr black hole under the same plasma parameters, the Teo wormhole has higher energy extraction power and efficiency. This is completely different from the Simpson-Visser rotating wormhole, which can reduce to a Kerr black hole, where the large spin makes efficiency and power decrease. We also extend magnetic reconnection to the plunging region. We find that when the spin is not particularly high, the energy extraction power and efficiency in the plunging region are higher than those in the circular orbit region, while for very high spin the situation is reversed. This conclusion also differs from that obtained from a Kerr black hole, where the power and efficiency in the plunging region are always higher than those in the circular orbit region.

China

Ke Wang

Wei Xu

Xiao-Xiong Zeng

Extracting energy from a traversable wormhole via magnetic reconnection: Circular orbits and the plunging region

The optimal chirped field for enhancing electron-positron (EP) pair production is explored using a quantum kinetic approach. First, the momentum spectrum and number density of EP pairs produced by Gaussian chirped fields are investigated. The results show that the momentum spectrum exhibits distinct interference patterns, while the number density grows monotonically with chirp parameters but oscillates with the carrier angular frequency. Moreover, the number density increases by four orders of magnitude compared to chirp-free fields. The results are further compared with those from four other chirped fields: frequency-modulated, linear, quadratic, and sinusoidal chirp. The analysis reveals that the maximum number density for sinusoidally chirped fields is the highest, followed by Gaussian, frequency-modulated, quadratically, and linearly chirped fields. This ranking also applies to the maximum enhancement factors for these chirped fields. Notably, the number density for sinusoidally chirped fields improves nine orders of magnitude compared to chirp-free fields. These results not only deepen our understanding of pair production in chirped fields but also provide significant optimization strategies for future vacuum pair production experiments.

Z.L. Li

Y.F. Chen

R.Z. Jiang

Y.J. Li

Enhancing pair production with optimized chirped electric fields

Ultracentral high-energy collisions between identical nuclei are very sensitive to the size and shape of the frozen configuration of nucleons at the instant of the collision, an information that is encoded in the ground-state wave functions of the colliding nuclei. The relative standard deviation of the size of the colliding system soon after the collision has recently been inferred from event-by-event fluctuations of the momentum per particle in collisions of 208Pb nuclei at the LHC, and since a single collision event produces thousands of particles, this information is very precise. We connect this extracted value to the magnitude of the zero-point fluctuations of the radius of the lead nucleus. The value that is extracted from the data is compatible with estimates based on nuclear sum rules, but is overestimated by classical Glauber-type modeling of high-energy collisions. The role of the Pauli principle in suppressing the fluctuations in closed-shell nuclei is underlined. It leads to a distinctive <italic>A</italic> dependence that could be checked in collisions of smaller systems.

France

Jean-Paul Blaizot

Jean-Yves Ollitrault

Accessing zero-point fluctuations in high-energy nuclear collisions

The covariant Gross-Pitaevskii-like equation for studying systems of interacting relativistic fermions is proposed. The Lagrangian generating such an equation is derived. The considered equation is examined in studying the Fermi-liquid, superconductivity and the confinement problem in QCD. The Migdal’s step in the Fermi-liquid model as well as the excitation spectrum of the superconductive fermion systems are derived in the context of the proposed Gross-Pitaevskii-like equation. We also show that the quark fields governing such an equation turn out to be confined in the (3+1) space-time in the QCD framework.

Russia

Andrew Koshelkin

Covariant Gross-Pitaevskii-like equation for relativistic fermions

India

Biplob Bhattacherjee

Abhinav Kumar

Swagata Mukherjee

Germany

Rhitaja Sengupta

Anand Sharma

Corrigendum to “From obstacle to opportunity: uncovering the silver lining of pileup” [Phys. Lett. B 873 (2026) 140121]

We analyze the on-shell content of the local Lorentz covariants of the five-dimensional spin-zero Duffin–Kemmer–Petiau algebra in elastic spin-zero–spin-1/2 scattering. The scalar, vector, and tensor structures are reduced explicitly to the two independent amplitudes allowed by the physical parity-conserving process. The two scalar structures are proportional on shell, the genuine nonminimal vector <italic>i</italic>[ <italic>P, &#946;&#956;</italic>] is longitudinal and vanishes after contraction with the conserved fermion vector current, and the projected vectors <italic>P&#946;&#956;</italic> and <italic>&#946;&#956;P</italic> each reduce to one half of the minimal-vector contribution. The tensor covariants introduce no additional on-shell directions. We discuss the consequences for the four invariant choices used in meson&#8211;nucleus optical-potential calculations and show that different nuclear equations can arise only after on-shell-equivalent representatives are promoted to optical operators and iterated beyond the order at which the elementary impulse approximation is fixed. These results provide a systematic basis for distinguishing genuinely independent elementary amplitudes from representation-dependent effects generated by the optical embedding.

Brazil

Luis B. Castro

On-shell reduction of spin-zero Duffin–Kemmer–Petiau covariants and implications for the relativistic impulse approximation

We investigate a class of charged radiating star models with nonzero shear in general relativity by incorporating an electromagnetic field into the framework of dissipative gravitational collapse. The interior spacetime is matched to the exterior charged Vaidya spacetime across a timelike hypersurface, and the Einstein–Maxwell field equations are derived in full. The modified junction conditions yield a charged boundary condition equation which is transformed into a Riccati equation through a particular choice of the gravitational potential associated with the areal 2-sphere. This Riccati equation is integrated exactly to obtain three distinct classes of exact solutions representing a new category of charged shearing metrics not previously studied. A comprehensive physical analysis confirms the physical plausibility of the solutions, demonstrating that electromagnetic charge plays a significant role in modifying the stability and structural complexity of realistic radiating stellar configurations.

M.M.M. Nasir

Jordan

Pakistan

Azerbaijan

M.Zeeshan Gul

S. Khan

Y. Xue

Riccati-driven exact solutions and physical viability of charged radiating stars

The long-standing quenching problem of Gamow-Teller (GT) strength in nuclear <italic>&#946;</italic>-decay is attributed to missing contributions in the transition operator and/or incomplete nuclear correlations in many-body wave functions. Recent studies have predominantly emphasized operator renormalization, including chiral two-body current (TBC), while many-body correlation effects&#8211;especially in heavy open-shell nuclei&#8211;have not received sufficient attention. We present a large-configuration shell-model calculation that incorporates TBC and treats both mechanisms on an equal footing. Taking the neutrinoless double <italic>&#946;</italic>-decay candidate 76Ge as an example, we demonstrate that strong nuclear correlations transfer a substantial portion of GT strength to high excitation energies, leading to a pronounced suppression of low-energy strength required for quenching. Our calculations thus suggest many-body correlations as the primary origin of GT quenching for this example, and reveal that quenching is not a local phenomenon but should be considered globally, taking into account all low-energy and highly excited states. Chiral TBC contributes only a modest reduction of <math altimg='si11.svg'><mrow><mn>5</mn><mo linebreak='goodbreak'>&#8722;</mo><mn>15</mn><mo>%</mo></mrow></math> for 76Ge, depending on the coupling constants employed. For other Ge isotopes, it is found that the TBC can quench the <math altimg='si9.svg'><msup><mi>&#946;</mi><mo>&#8722;</mo></msup></math> decay rate by about 16% for 78,80,82Ge and about 10% for 84Ge.

Hao Zhou

Long-Jun Wang

Yang Sun

Gamow-Teller transitions in Ge isotopes: Effect of many-body correlations and two-body currents

We study the scalar diquark mass and the quark–diquark potential by applying a HAL QCD-inspired potential method to a baryonic system composed of a scalar diquark and a static quark. The diquark mass is determined self-consistently by requiring that the P-wave baryonic spectrum obtained from two-point correlators be reproduced within the potential framework. Numerical calculations are performed using <math altimg='si8.svg'><mrow><mn>2</mn><mo linebreak='goodbreak'>+</mo><mn>1</mn></mrow></math> flavor QCD gauge configurations generated by the PACS-CS Collaboration on a <math altimg='si9.svg'><mrow><msup><mi>L</mi><mn>3</mn></msup><mo linebreak='goodbreak'>&#215;</mo><mi>T</mi><mo linebreak='goodbreak'>=</mo><msup><mn>32</mn><mn>3</mn></msup><mo linebreak='goodbreak'>&#215;</mo><mn>64</mn></mrow></math> lattice with <math altimg='si10.svg'><mrow><msup><mi>a</mi><mrow><mo>&#8722;</mo><mn>1</mn></mrow></msup><mo>&#8776;</mo><mn>2.176</mn></mrow></math> GeV and the pion mass, <italic>m<inf>&#960;</inf></italic>&#8239;&#8776;&#8239;702 MeV. From the analysis, we obtain a scalar diquark mass which is close to the na&#239;ve constituent quark estimate (2/3) <italic>m<inf>N</inf></italic>, together with a quark&#8211;diquark potential of the Cornell type (Coulomb + linear). The string tension extracted from the quark&#8211;diquark potential agrees within approximately 5% with that obtained from the static quark&#8211;antiquark potential (Wilson Loop).

Japan

Kai-Wen Kelvin-Lee

Noriyoshi Ishii

Scalar diquark mass and quark–diquark potential from lattice QCD using the potential method with a static quark

Angular momentum generated in relativistic fragmentation reactions remains one of the major uncertainties of reaction models. In this Letter, we show that fragmentation-induced fission provides an independent and sensitive probe of the angular momentum carried by the compound nuclei after the collision. The dynamical intranuclear cascade model INCL, coupled to the de-excitation code ABLA, is benchmarked against measured fission cross sections and fission-fragment charge-distribution widths, as well as available isomeric-ratio data for fragmentation residues. Scaling down the angular momentum predicted by INCL leads to a systematic underprediction of both fission observables, whereas the default calculations consistently reproduce the experimental data. We also investigate the effect of the angular-momentum dependence of the stiffness parameter on the charge-distribution widths. The GEF parametrization, when implemented in ABLA, overestimates the charge-distribution widths, whereas a weaker dependence, consistent with Rusanov’s parametrization, improves the agreement with the data. Finally, the INCL+ABLA calculations provide a significantly better description of the population of high-spin isomeric states than standard abrasion models based on the Glauber formalism and the Goldhaber approach, supporting the broader angular-momentum distributions predicted by INCL.

Spain

J.L. Rodríguez-Sánchez

M. Feijoo

J.C. David

A. Graña-González

J. Hirtz

Insights into the angular momentum of compound nuclei populated in fragmentation-induced fission reactions of 238U