Papers

Quantum-information observables have emerged in recent years as new tools in nuclear and particle physics, from entanglement in top-quark pairs to spin correlations in $\Lambda\bar{\Lambda}$ production. Extending these studies to unequal-spin hadronic final states poses a fundamental challenge: the $6\times6$ density matrix of a qubit-qutrit system contains 35 independent spin parameters, but the decays of $\Lambda V$ pairs, with $V=\phi$ or $K^{*0}$, provide access to only 23 due to the hidden vector polarization from the strong decay. In this Letter, we formulate a qubit-qutrit quantum tomography (QQQT) technique for these spin-$\tfrac{1}{2}\otimes1$ systems and establish exact criteria for entanglement certification from the incomplete density matrix. Compared with the $\Lambda\bar{\Lambda}$ system, QQQT of $\Lambda\phi$ and $\Lambda K^{*0}$ provides a new probe of nonperturbative QCD hadronization, enabling a direct comparison of the spin evolution of entangled quark pairs produced from the vacuum as they hadronize into a baryon or a vector meson.

Thermal neutron-induced fission of $^{235}$U is studied using a six-dimensional Langevin approach based on the Cassini shape parametrization. Scission events are classified into Asymmetric 1 (AS1), Asymmetric 2 (AS2), and Superlong (SL) fission modes by applying the $k$-means algorithm to the fragment mass and the quadrupole deformations of both fragments. For each mode, proton and neutron single-particle levels are calculated for representative fragments to examine their shell structures. The AS1 heavy fragment exhibits proton gaps at $Z=50$ and 52 and neutron gaps at $N=82$ and 84, whereas well-developed gaps appear at $Z=56$ and $N=88$ in the AS2 heavy fragment. The mass splits of AS1 and AS2 are close to those of the conventional Standard I and Standard II modes, respectively. However, the average total kinetic energy is lower for AS1 than for AS2, opposite to the conventional ordering of Standard I and Standard II. This reversal reflects the more elongated shape of the AS1 light fragment. The SL mode is conventionally interpreted in terms of macroscopic liquid-drop effects, whereas the pronounced proton shell gap at $Z=46$ suggests that proton shell effects also contribute to the elongated symmetric configuration. The classification based on fragment mass and the quadrupole deformations of both fragments provides a basis for distinguishing fission modes and examining the corresponding fragment shell structures at scission.

The fission of $^{258}\mathrm{Md}^{*}$ is calculated in the excitation energy range of $E^{*} = 6$–$36$~MeV using a six-dimensional Langevin framework with the Cassini shape parametrization. The calculated events are classified into two symmetric and two asymmetric fission modes based on the fragment mass and the quadrupole deformations of the two fragments at scission. The symmetric modes are the short mode with high total kinetic energy (TKE) and the superlong mode with low TKE, whereas the asymmetric modes differ in mass asymmetry. With increasing excitation energy, the yield of the short mode decreases, whereas the combined yield of the two asymmetric modes increases, as observed in the in-beam prompt-fission study of $^{258}\mathrm{Md}^{*}$. From an analysis of the fragment shapes and associated single-particle levels, the short mode and the dominant asymmetric mode with the smaller mass asymmetry are found to involve a compact fragment characterized by deformed shell gaps at $Z = 52$ and $N = 84$, while the complementary fragment is compact in the short mode and strongly elongated in the asymmetric mode.

We present a lattice-QCD determination of properties of the lightest scalar, pseudoscalar, vector, and axial-vector heavy-strange mesons. This includes the decay constants of all mesons, and the binding energies and Weinberg compositeness parameters of the positive-parity states. The calculations are performed with domain-wall fermions for the light and strange quarks and anisotropic clover actions for the charm and bottom quarks. We use seven ensembles generated by RBC/UKQCD with pion masses ranging from 431 MeV to 139 MeV and lattice spacings ranging from 0.114 fm to 0.073 fm, which allows us to perform combined chiral and continuum extrapolations. For the negative-parity mesons, we obtain $f_{D_s}=251.4(2.1)(0.4)(2.5)\:{\rm MeV}$, $f_{D_s^*}=272.5(4.3)(1.0)(2.7)\:{\rm MeV}$, $f_{B_s}=228.4(5.8)(0.5)(2.3)\:{\rm MeV}$, $f_{B_s^*}=229.2(4.4)(0.8)(2.3)\:{\rm MeV}$, $f_{D_s^*}/f_{D_s}=1.086(14)(11)$, and $f_{B_s^*}/f_{B_s}=1.003(22)(10)$. In the positive-parity sector, the finite-volume energies and decay constants are extracted using the GEVP from correlation matrices with three different types of hadron interpolating operators, including operators with covariant derivatives and meson-meson-scattering operators at both source and sink. After extrapolation to the physical point, we obtain $f_{D^*_{s0}}=136.6 (8.0)(4.0)(1.4)$ MeV, $f_{D_{s1}}=200 (33)(24)(2)$ MeV, $f_{B^*_{s0}}=207 (12)(8)(2)$ MeV, and $f_{B_{s1}}= 196 (16)(11)(2)$ MeV. Our results for $f_{B^*_{s0}}$ and $f_{B_{s1}}$ are the first from lattice QCD. Lüscher's method is used to find the infinite-volume bound-state masses. At the physical point, we obtain $m_{D^*_{s0}}-m_D-m_K=-48 (14)(4)$ MeV, $m_{D_{s1}}-m_{D^*}-m_K=-61 (15)(2)$ MeV, $m_{B^*_{s0}}-m_B-m_K= -69 (13)(4)$ MeV, and $m_{B_{s1}}-m_{B^*}-m_K=-77 (10)(5)$ MeV. Our analysis shows consistency with the positive-parity states being predominantly molecular.

Magnetic dipole, $M1$, strengths were studied in semi-magic $^{50}$Ti up to the neutron-separation threshold by combining data from $(d,p)$ one-neutron transfer, $(\gamma,\gamma')$ real-photon scattering, $(e,e')$ inelastic scattering at extreme backward angles, and $(p,p')$ at $E_p = 210$ MeV and extreme forward angles. The combination of all probes provided unique access to the neutron spin-flip contribution and the possibility to evaluate its role in generating the spin-flip $M1$ strengths. The small contribution of the neutron $(1f_{7/2})^{-1}(1f_{5/2})^{+1}$ spin-flip transitions, which were probed with the $(d,p)$ reaction, to the overall strength in $^{50}$Ti questions the standard picture for the microscopic origin of spin-flip strength in the $fp$ shell. For $^{50}$Ti, this letter shows that $J^{\pi} = 1^+$ states with larger neutron $(1f_{7/2})^{-1}(1f_{5/2})^{+1}$ spectroscopic factors do not correspond to the ones with the largest $B(M1;0^+_1 \rightarrow 1^+_i)$ strengths.

We develop an Efficient Wake procedure for computing the distribution of hadrons originating from jet wakes in heavy ion collisions - the hydrodynamic response of a droplet of quark-gluon plasma to the energy and momentum deposited in it by high-energy partons propagating through it. The procedure employs the linearity of linearized hydrodynamics and takes account of the effects of both longitudinal expansion and transverse radial flow on the hydrodynamic evolution of the wakes and on the resulting particle production at the freezeout hypersurface. It makes repeated use of template solutions to linearized hydrodynamics in a Bjorken flow background with no transverse flow, templates that need only be computed once, and uses suitable rotations and boosts to map fluctuations from these templates to fluctuations at a point on the freezeout hypersurface in a way that incorporates the effects of the radial flow. We benchmark this procedure by comparing its results to results obtained from full $(3+1)$-dimensional nonlinear hydrodynamics calculations, find reasonable agreement, and find that our Efficient Wake procedure yields a much better description of the distribution of hadrons originating from jet wakes than does the older oversimplified procedure employed in the Hybrid Model. And, the Efficient Wake procedure is computationally efficient: it is at least tens of thousands of times faster than full nonlinear hydrodynamics calculations. Hence, we anticipate that when our new procedure is implemented in Monte Carlo analyses of jets in heavy ion collisions, for example in the Hybrid Model, it will greatly improve the description of the soft component of many jet and jet substructure observables as compared to experimental data.

Nuclides for which extended sets of E2 matrix elements have been measured by means of COULEX experiments are studied in the framework of the triaxial projected shell model (TPSM). The studies encompass: 70,72,74,76Ge, 76,78,80,82Se, 100Mo, 104Ru, 110Pd, 168Er, 186,188,190Os, 184Pt. The experimental energies of the ground band, of the quasi gamma band and of some excited 0+ bands as well as their individual intra and inter band matrix E2 matrix elements are systematically accounted for by the microscopic TPSM calculations.

The M1 and E2 {\gamma} strength functions ({\gamma}sf) have been calculated for extended series of the Mo, Fe, Sn, Ge and Gd isotopes using the conventional spherical shell model (SSM) and, as a new tool, the triaxial projected shell model (TPSM). For almost all cases the strong enhancement of the M1 {\gamma}sf (low energy magnetic radiation-LEMAR) is found. In the mid-shell region, a bimodal structure of the LEMAR spike and a bump around 3 MeV, interpreted as the scissors resonance (SR), develops. The combination of LEMAR and the SR is generated by the splitting of the spherical single particle multiplets of given j caused by deformation and their fragmentation over nearby quasiparticle configurations.

A critical component of relativistic three-body scattering amplitudes is the one-particle exchange (OPE) process, wherein a single particle is exchanged between incoming and outgoing two-body subsystems. We present an improved, finite-sum expression for the partial-wave OPE that is valid for three massive, spinless particles in arbitrary angular momentum configurations. A collection of analytic and numerical checks demonstrate that our finite-sum expression reproduces the known properties of the partial-wave OPE, including its threshold scaling behavior and singularity structure. Compared with previous work, this result more efficiently handles the rapid proliferation of partial waves contributing to any total angular momentum $J$, enabling the construction of robust wavesets for three-body amplitude analyses.

We present a pedagogical showcase of BRST quantization for restoring symmetries in nuclear many-body systems as a reformulation and potential alternative to conventional projection methods. The formalism is illustrated using translational invariance for a simple system of two interacting masses in one dimension, but with an eye toward generalizing to more particles, higher dimensions, and other symmetries. We explain the considerations underlying particular choices within the BRST construction, and develop both Hamiltonian and path integral formulations to provide guidance for the variety of many-body and effective field theory contexts where gauge fixing for symmetry restoration might be useful. For the demonstration system we show how to diagonalize within the extended BRST phase space, how variation after projection is recovered for product reference states, how the corresponding gauge-fixed functional integral is constructed, and how collective zero modes are isolated and controlled. Throughout, we keep in mind extensions of BRST symmetry to various approximation schemes as a guide for consistent symmetry restoration.

We formulate, within a fixed FSI-improved amplitude convention, a zero-locus diagnostic for the direct contact term in $\phi\to\pi^+\pi^-\pi^0$. The resonant $\rho\pi$ contribution is dressed channel by channel with the complex Omnès function, the direct term is multiplied by the averaged Omnès factor, and a real constant background is retained as a smooth residual amplitude. In this convention, $F^{\rm FSI}=R+c e^{i\delta_{\rm dir}}D$ with $c=g_{\phi3\pi}^{\rm eff}$, and the difference of two constrained invariant-mass gradients of the reduced Dalitz density gives a local quadratic identity for $c$ on the zero-contour. The construction provides a closure and stability diagnostic complementary to a global Dalitz-plot fit. For the benchmark input $g_{\phi3\pi}^{\rm eff}=-24.0~{\rm GeV}^{-3}$, we identify a numerically stable zero-contour branch around $M_{+0}=0.460\pm0.025~{\rm GeV}$ and $M_{+-}\le0.560~{\rm GeV}$, where the tight-contour median estimator reproduces $g_{\phi3\pi}^{\rm est}\simeq -24.0~{\rm GeV}^{-3}$, a closure recovery of the injected coupling within the chosen FSI-improved convention rather than an independent extraction. We further vary the mass-window selection of the branch. The median remains close to the injected value under shifts of the $M_{+0}$ window and moderate changes of its width, while the mean and standard deviation are more sensitive to outlier points near unstable quadratic branches. The method therefore identifies Dalitz-plane regions where the direct-term interference is locally well-conditioned and provides useful guidance for control-region choices and systematic variations in future global fits.

We present a modular implementation of next-to-leading order (NLO) perturbative QCD (pQCD) thermodynamics with finite strange quark mass in the MUSES Calculation Engine, enabling reproducible connections between high-density QCD calculations and neutron star observables. Using this implementation, we investigate the interplay between flavor symmetry and physically motivated renormalization-scale prescriptions in cold, $\beta$-equilibrated quark matter. We compare prescriptions associated with the conserved-charge $BQS$, isospin $BI_3S$, and $SU(3)$ Cartan $BI_3Y$ bases, and show that their different symmetry properties at finite perturbative order can significantly affect the predicted flavor composition. In particular, while the $BQS$ and $BI_3Y$ prescriptions yield the same reduced $\beta$-equilibrated \eos{} for $\mu_S=0$, they can predict different flavor compositions, whereas the $BI_3S$ prescription generates additional contributions to the charge-neutrality condition and develops strong scale dependence at low chemical potentials. We then apply stability and causality constraints to investigate the effect of the strange quark mass on the neutron star \eos{}. In an exploratory benchmark at $\mu_B=2.4$~GeV and fixed fiducial renormalization scale, increasing the fixed strange quark mass from $m_s=0$ to $m_s=300$~MeV reduces the fraction of \eos{} in our prior that is incompatible with the pQCD constraint from 51% to 36% and qualitatively changes the region of \eos{} space that is selected, retaining greater support for stiffer behavior. These results motivate systematic studies of strange quark mass and renormalization-scale uncertainties in pQCD constraints. The MUSES implementation provides a modular framework for such extensions and for future higher-order calculations.

Excited states of semi-magic $^{50}$Ti were studied up to the neutron-separation energy via the $(d,p)$ and $(d,p\gamma)$ reactions. In total, 82 excited states were identified based on the measurement of angular distributions with the Super-Enge Split-Pole Spectrograph (SE-SPS) at Florida State University. From the experimental data, sum rules related to vacancies were calculated for the $2p_{3/2}$, $2p_{1/2}$, $1f_{5/2}$, $1g_{9/2}$, and $2d_{5/2}$ neutron single-particle orbitals and compared to predictions obtained with the time-dependent continuum shell model (TDCSM), the quasiparticle-phonon model (QPM), and the relativistic equation of motion theory (REOM$^3$). A comparison for the $(d,p)$ data obtained for $^{51}$Ti and $^{50}$Ti is also presented, focusing on differences of the single-particle strength fragmentation in even-$A$ and odd-$A$ nuclei.

We initiate the study of two-to-two scattering amplitudes involving two distinct scalar particles in $d = 4$ spacetime dimensions using the primal S-matrix bootstrap. We impose a $\mathbb{Z}_2 \times \mathbb{Z}_2$ global symmetry under which the two particles are the lightest ones carrying charges $(-,+)$ and $(+,-)$, guaranteeing their absolute stability and absence of triangular anomalous thresholds. For unequal masses, the presence of a pseudo-physical cut whose discontinuity is not directly constrained by physical unitarity qualitatively changes the bootstrap problem. We find several observables to be unbounded, while others obey non-trivial one-sided bounds or become bounded once another observable is fixed. In the equal-mass limit, where the pseudo-physical region disappears, two-sided bounds are recovered. As a proof of concept, we show that supplying information about the pseudo-physical discontinuity through an Omnès parametrisation also restores boundedness. Our results provide a starting point for future studies of physical processes such as pion-kaon and pion-nucleon scattering.

The entangling power of a unitary operator acting on a bipartite Hilbert space measures the entanglement it generates from product states, averaged over the inputs. A finite-dimensional unitary has a spectral decomposition $U=\sum_{a=1}^{n}e^{i\theta_a}P_a$, where $e^{i\theta_a}$ are the eigenvalues, $P_a$ the corresponding eigen-projectors, and $n$ is the number of distinct eigenvalues. After removing an overall phase, the entangling power is a function on the $(n-1)$-torus of relative eigenphases at fixed spectral projectors. We prove that this function is stationary at all $2^{n-1}$ points on the torus where every relative phase is $0$ or $\pi$, which we define as corners. Up to an overall phase, $U$ at each corner is a generalized reflection $R=\mathbb{I}-2Q$ satisfying $R^2=\mathbb{I}$, where $Q$ is the sum of spectral projectors whose relative phase is $\pi$. At the corner the entangling power is expressed in terms of seven local-unitary invariants of $Q$. A unitary gate $U$ can be realized as a corner of some projector family if and only if $U^2\propto\mathbb{I}$, a condition satisfied by many Clifford and non-Clifford gates. We illustrate the theorem with two-qubit gates, $SU(N)$ channel decompositions, and two-site spin chains, obtaining examples of minima, maxima, and saddle points. In addition, a corner that is a saddle point on the full phase torus can appear as a local maximum or minimum along different time-evolution trajectories.

Neutron stars (NSs) provide a unique laboratory for testing gravity in the strong-field regime and for searching for deviations from General Relativity (GR). In this work, we investigate the effects of Energy-Momentum Squared Gravity (EMSG) on NS structure and examine whether its signatures can be identified from observable stellar properties using supervised machine learning (ML). We solve the modified Tolman-Oppenheimer-Volkoff equations for approximately $10^{4}$ nuclear equations of state (EOSs) for EMSG coupling parameters $\alpha=\{-5.01,-2.50,0,+2.50,+5.01\}\times10^{-38}\,\mathrm{erg}^{-1}\mathrm{cm}^{3}$, and calculate the gravitational mass $M$, radius $R$, dimensionless tidal deformability $\Lambda$, and fundamental $f$-mode oscillation frequency for each stellar configuration. Imposing observational constraints on $M$, $R$, and $\Lambda$, we split our datasets into train and test sets, and we employ Random Forest (RF), K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Logistic Regression (LR), and Gaussian Naive Bayes (GNB) to classify the representative sectors $\alpha=\{-5.01,0,+5.01\}\times10^{-38}\,\mathrm{erg}^{-1}\mathrm{cm}^{3}$ using $(M, R,\Lambda,f)$. The RF classifier performs best, achieving an accuracy of approximately $99.85\%$ with precision, recall, and F1-scores exceeding $99.8\%$, while KNN also achieves accuracy above $99\%$. The nearly diagonal confusion matrices demonstrate that the observationally viable NS configurations associated with different EMSG sectors remain highly separable in the multidimensional observable space. Our results show that NS observables retain robust signatures of EMSG even after observational filtering, establishing ML-assisted NS observations as a promising complementary approach for probing modified gravity with current and future multi-messenger observations.

Attractors are effective low-dimensional structures, defined in a chosen set of observables, that trajectories from different initial states approach; hydrodynamic attractors are those on which the late-time evolution is governed by hydrodynamic constitutive relations. Motivated by nuclear collisions and ultracold atomic gases, this chapter distinguishes attractorization (the loss of sensitivity to some directions in the space of initial states) from hydrodynamization (the onset of validity of hydrodynamic constitutive relations). Using mainly conformal, boost-invariant Bjorken flow, we compare Müller-Israel-Stewart-type theories, kinetic theory, holography, and classical Yang-Mills fields. Forward attraction, produced by the decay of non-hydrodynamic modes, is distinguished from pullback attraction, which can select a unique regular solution, and from expansion-driven attraction, which can suppress initial-state sensitivity before microscopic relaxation, with or without a subsequent fluid regime. Divergent gradient expansions and their transseries completions, the state-space picture, and adiabatic hydrodynamization provide complementary descriptions. Applications to nuclear collisions include particle production, transverse energy and flow, the initialization of and linear response around attracting backgrounds, jet quenching, and attractor-informed modifications of hydrodynamic models. For ultracold Fermi gases, we review theoretical proposals for bulk-channel attractors under scattering-length drives and distinguish them from recent measurements of short-time contact and momentum-distribution dynamics.

Motivated by recent progress in data-driven approaches, we introduce a machine-learning (ML)-informed Debye mass, extracted from lattice-informed inputs, exclusively in the complex-valued heavy-quark Kent State University (KSU) potential. The resulting complex potential is used to solve the real-time Schrödinger equation within the quantum trajectories (QTraj) framework for the evolution of bottomonium in the quark-gluon plasma. We then compute the nuclear modification factors and double ratios for bottomonium $\Upsilon(1S)$, $\Upsilon(2S)$, and $\Upsilon(3S)$ states in Pb-Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV. We compare our ML-induced results with those from the original KSU model and with experimental measurements from ALICE, ATLAS, and CMS collaborations. We find that the machine-learned Debye mass leads to improved agreement with data, particularly for excited states, highlighting the utility of machine learning in modeling in-medium QCD effects.

In our previous work [C. Lorcé et al., Phys. Lett. B 868 (2025) 139792], we investigated the 2D spatial distributions of transverse total angular momentum, including orbital angular momentum and intrinsic spin, relative to the canonical center (or center of spin). In the present work, we extend this analysis in two directions. First, we study the corresponding transverse boost distributions relative to the canonical center. Second, since the definition of generalized angular momentum density depends crucially on the choice of pivot, we analyze how the spatial distributions of transverse total angular momentum and boost are modified when they are defined relative to different relativistic centers, viz.~the relativistic centers of mass, energy, and spin. Considering spin-1/2 targets, we derive the corresponding 2D spatial distributions in the transverse plane, and further investigate how the spatial patterns evolve under longitudinal Lorentz boosts. Additionally, we provide the corresponding light-front distributions in the transverse plane, establishing a clear connection between the instant-form and light-front descriptions of transverse angular momentum and boost.

We show that the Chiral Mean-Field model (CMF) can produce a phase diagram with three critical points: the nuclear liquid-gas transition, quark deconfinement, and a strangeness driven transition. The strangeness driven transition separates a mainly nucleonic phase from one dominated by hyperons and baryon resonances. We discuss the compositional change in these transitions and their possible signatures in heavy-ion collisions and neutron star mergers.

Separable representations of the Ernst–Shakin–Thaler type are constructed for the charge-dependent Bonn (CD~Bonn) nucleon–nucleon potential ($j\le4$; $nn$, $np$, $pp$), for the Kanada–Kaneko–Nagata–Nomoto (KKNN) $\alpha N$ interaction, and for the Buck–Friedrich–Wheatley (BFW) $\alpha\alpha$ interaction. They are the input for momentum-space Faddeev calculations of $A=3$, $6$, $9$, and $12$ systems. The representations are tested against six acceptance criteria: off-shell accuracy at the pair energies sampled by the three-body kernel, phase shifts, effective-range parameters, bound and resonant states, and numerical stability.

Following important experimental developments, tests of the Diffuse Supernova Neutrino Background (DSNB) are entering a new phase that might lead to a discovery. This motivates the development of simple and broadly applicable tools for comparing theoretical predictions and interpreting experimental results. We show that, over the energy range relevant to current detectors, the DSNB is well described by an exponential spectrum, characterized by the differential flux at 20 MeV, $\phi_{20}$, and a spectral energy scale, $E_0$. We fit the spectra of 24 representative models and demonstrate that the exponential description provides an excellent approximation. We then recast the recent Super-Kamiokande results in the $(\phi_{20},E_0)$ plane, showing that model-specific best fits and upper bounds can be interpreted naturally within this framework. Our results indicate that, above realistic detection thresholds, and until the precision phase is reached, the observable DSNB is effectively a two-parameter phenomenon. We advocate that the $(\phi_{20},E_0)$ parameterization be adopted as a standard, to be used routinely to report future theoretical predictions and experimental results.

The poorly constrained density dependence of the nuclear symmetry energy introduces significant uncertainties in the equation of state (EOS) of dense nuclear matter and, consequently, in neutron-star properties. We systematically investigate how uncertainties in the symmetry energy $E_{\rm sym}$ and its slope $L$ at saturation density $n_0$ affect NS properties within the relativistic mean-field (RMF) framework, including the effects of nonlinear $\sigma$-$\delta$ coupling and possible admixture of dark matter(DM) . For fixed $E_{\rm sym}(n_0)$ and $L(n_0)$, we find that the $\sigma$-$\delta$ coupling with $g_{\sigma\delta}=-0.004$ induces an abnormal softening of the EOS, which simultaneously increasing the maximum NS mass and reducing the stellar radius and tidal deformability. A similar behavior is found in the presence of DM with Fermi momentum $k_F^{\rm DM}=50~\mathrm{MeV}$ at $E_{\rm sym}(n_0)=36~\mathrm{MeV}$. In this case, the RMF EOS satisfies the tidal-deformability constraint from GW170817. We further find that the surface curvature of NSs is strongly correlated with the stiffness of $E_{\rm sym}$, with softer symmetry energy corresponding to larger surface curvature. Our results also indicate that the behavior of $E_{\rm sym}$ around $n_0$ is mainly governed by isoscalar rather than isovector parameters.

We apply transfer learning (TL) to construct data-driven models of inclusive electron-nucleus cross sections. Starting from an ensemble of deep neural networks pretrained on \(^{12}\)C data, we fine-tune the models separately for \(^{3}\)He, \(^{6}\)Li, \(^{16}\)O, \(^{27}\)Al, \(^{40}\)Ca, and \(^{56}\)Fe. The resulting models improve for all targets, marginally so for oxygen, where the carbon baseline is already adequate, although their predictive robustness depends on the amount, coverage, and precision of the available target data. We systematically study how model performance depends on the number of fine-tuned layers, on the fraction and selection of the training data, and on the overlap between the source and target kinematic domains. The layer-wise analysis shows that oxygen requires only shallow adaptation, whereas helium, calcium, and iron require substantially deeper fine-tuning. Lithium represents the least robust case because of its limited dataset, while aluminum demonstrates a strong sensitivity to a small subset of highly constraining measurements. For selected kinematic configurations outside the coverage of the carbon training data, the adapted models remain consistent with the measurements within their estimated uncertainties. Finally, we compare the resulting predictions with those of the phenomenological F1F2 model.

We analyze the high-momentum tails of nucleon distributions in nuclei using the operator product expansion (OPE) and Pionless effective field theory. The OPE factorizes the distributions into Wilson coefficients, determined from two-nucleon scattering, and local-operator matrix elements (LOMEs). Because the leading ${{}^1S_0}$ and ${{}^3S_1}$ Wilson coefficients are nearly degenerate in the single-nucleon distribution, we construct the OPE of the two-nucleon momentum distribution, which separates the two contributions into distinct spin-isospin channels. From variational Monte Carlo two-nucleon distributions of \isotope[3]{He}, \isotope[4]{He}, \isotope[6]{Li}, and \isotope[12]{C}, we extract the LOMEs and accurately reconstruct the single-nucleon distributions at large momenta. In potentials without explicit non-nucleon degrees of freedom such as AV18, the Wilson coefficients of the single- and two-nucleon OPEs are proportional, yielding approximate relations between the two distributions.

Motivated by renewed interest in the light-cone distributions of $P$-wave quarkonia, we investigate the leading-twist distribution amplitudes of these states within the basis light-front quantization (BLFQ) formalism. While our extracted distributions exhibit macroscopic shapes consistent with expectations from the non-relativistic limit, we find that relativistic effects introduce critical structural features. Most notably, we observe novel “W"-shaped structures in the distribution amplitudes of the axial vector mesons, which arise from relativistically induced $S/D$ partial waves and cannot be explained by non-relativistic dynamics. These findings provide essential non-perturbative inputs for analyzing hard exclusive processes and highlight the importance of relativistic frameworks for understanding heavy quarkonium production and structure at modern high-energy colliders.

We revisit single-inclusive gluon production in the dilute–dilute limit of the Color Glass Condensate and show that $k_\perp$-factorization is only the zeroth order of a systematic gradient expansion in the transverse positions of the two colliding sources, organized in powers of $1/(Q_sR)$, with $Q_s$ the saturation scale and $R$ the size over which the sources vary. Collecting terms order by order builds a ladder of scalar and tensor structures from the local distributions and their transverse derivatives, yielding an extended $k_\perp$-factorized formula that retains the spatial dependence of the sources and, through kinetic moments of the spectrum, the energy-momentum tensor. Repeating the expansion from a real-time computation of the classical Glasma fields in the future light cone reproduces the momentum-space result in the eikonal limit, but additionally retains coherent interference between amplitude and conjugate. This adds terms to the ladder (flow responses, chromo-electric–magnetic interference, and a longitudinal energy flux) further suppressed by powers of the large outgoing momentum $|\pp|\gg Q_s$. The hierarchy thus reveals momentum-space anisotropies present in the initial state before any hydrodynamic evolution, which leading $k_\perp$-factorization misses by construction. Since each order is a local operator on the same unintegrated distributions, these corrections can be added directly to existing saturation-based initial-state models, giving a dynamically generated initial momentum anisotropy and a more faithful early-time energy-momentum tensor without abandoning the tractable factorized form. Set by gradients of the transverse density profiles, they grow towards more dilute, fluctuation-dominated systems, e.g. light-ion collisions. Phenomenological consequences will be developed in a companion paper.

We present an EOS-driven extension of the NSCool thermal evolution code that enables complete tabulated equations of state to be treated within a single composition-based input structure. The generalized NEW interface includes additional baryonic fractions, a bosonic composition variable, the hadronic volume fraction, and quark fractions, allowing nucleonic, hyperonic, resonant-baryonic and hybrid hadron-quark configurations to be handled within the same workflow. The neutrino sector is extended accordingly, including updated nucleonic modified Urca and bremsstrahlung rates, additional baryonic direct Urca channels, hyperonic processes, baryonic pair breaking and formation and quark direct Urca, modified Urca, bremsstrahlung and PBF contributions. In mixed phases, emissivities and the corresponding core heat capacity contributions are evaluated from phase-local quantities and combined using the hadronic volume fraction. The implementation is validated against the original NSCool calculation for a controlled nucleonic benchmark and demonstrated with representative hadronic and quark-containing EOSs. These calculations are intended as software validation tests of the generalized workflow rather than as observational fits or statistical EOS inference.

We find a quantum-geometric Meissner response in magnetized two-flavor color-superconducting (2SC) quark matter. Landau quantization quenches the transverse quasiparticle dispersion, suppressing the conventional Fermi-surface contribution and giving rise to a Meissner response governed by the quantum geometry of the Landau levels. In the strong-field regime, the response becomes dominated by the quantum metric of the lowest Landau level (LLL), and the leading scaling of the transverse Meissner mass is consequently set by the pairing gap, in contrast to the chemical potential scaling of conventional color superconductors. This unconventional scaling has a topological origin, as the LLL quantum metric is constrained by its Chern number. The reduced transverse Meissner mass provides potential implications for kHz quasi-periodic oscillations in magnetars.

We report on the $\beta$-delayed proton and $\gamma$-ray emission from $^{25}\mathrm{Si}$, measured at the Facility for Rare Isotope Beams (FRIB). Low-energy $^{25}\mathrm{Si}$ ions extracted from the Advanced Cryogenic Gas Stopper were implanted into a thin carbon foil surrounded by a compact, highly segmented array of silicon detector telescopes and two high-purity germanium detectors. This setup provides high-resolution charged-particle spectroscopy, establishing a proof of principle for precision stopped-beam decay studies at FRIB. We reconstruct the $^{25}\mathrm{Si}$ decay scheme, resolving new high-energy proton transitions and determining the feeding to excited states in $^{24}\mathrm{Mg}$. The observation of spectral interference patterns enables firm spin and parity assignments for highly excited states in $^{25}\mathrm{Al}$. The $^{25}\mathrm{Si}$ $\beta$-strength distribution is extracted and compared with large-scale shell-model calculations.