Abstract: Multi-TeV gamma-ray emission around eHWC J1850+001 (a source from the first HAWC catalog of gamma-ray sources emitting above 56 TeV) is spatially coincident with the pulsar wind nebula (PWN) G32.64+0.53, powered by PSR J1849-0001. The absence of counterparts in radio, optical, and GeV energy ranges, contrasted with clear detections in X-rays and very-high-energy (VHE) gamma rays, is indicative of a nonthermal leptonic origin for the nebula. We apply a systematic analysis pipeline, including a sophisticated model for the Galactic diffuse emission, to 2860 days of data from the HAWC Observatory. Our detailed analysis confirms that the ultra-high-energy (UHE) emission originates from G32.64+0.53, and we measure its spectrum up to 270 TeV with significant emission well beyond 100 TeV. We fit the multiwavelength observations with a time-dependent leptonic model powered by the pulsar's rotational energy, and the results establish the nebula as a leptonic PeV accelerator, capable of accelerating electrons to a maximum energy of Ecut >= 2.9 PeV (95% one-sided lower bound). The model also constrains the nebular magnetic field to 4.28 μG, supporting a leptonic PWN origin for the observed UHE emission.

Abstract: We present an FPGA-based study of the acceleration of matrix-element computations for Monte Carlo event generation, using MadGraph5_aMC@NLO as a benchmark framework. Two complementary benchmarks are considered. First, we map the phase-space-generation and matrix-element-evaluation stages of the benchmark process e(+) e(-) -> mu(+) mu(-) onto an AMD Alveo U250 accelerator, enabling a compute-only assessment of the mapped FPGA pipeline. Second, for the more complex gg -> t (t) over bar + X processes with increasing jet multiplicity, we investigate FPGA acceleration of the colour-algebra kernels as structured targets for selective acceleration. In this second case, the reported speedups correspond to the isolated colour-reduction kernel operating on precomputed amplitudes, rather than to the full matrix-element evaluation or the complete event-generation workflow. The proposed implementations are developed using High-Level Synthesis and are evaluated in terms of numerical accuracy, performance, device-level energy efficiency, resource utilisation, and scalability. Under the stated compute-only measurement methodology, the FPGA implementations achieve substantial speedups and lower energy per event than the evaluated CPU and GPU baselines. For the considered benchmarks, the numerical results show good agreement on average with the corresponding CPU reference calculations, while the resource analysis highlights the importance of numerical representation in determining FPGA scalability. Taken together, these results demonstrate the potential of FPGAs for accelerating selected matrix-element and colour-algebra kernels, while further integrated evaluation is required to determine their end-to-end benefit within heterogeneous Monte Carlo event-generation workflows in high-energy physics.

Abstract: Neutrino-nucleus cross section measurements are critical for future neutrino oscillation analyses. However, our models to describe them require further refinement, and a deeper understanding of the underlying physics is essential for future neutrino oscillation experiments to realize their ambitious physics goals. Current neutrino cross section measurements provide clear deficiencies in neutrino interaction modeling, but almost all are reported averaged over broad neutrino fluxes, rendering their interpretation challenging. Using the concept of deep underground neutrino experiment-precision reaction independent spectrum measurement (DUNE-PRISM)-a movable near detector that samples multiple off axis positions-neutrino interaction measurements can be used to construct narrow virtual fluxes (less than 100 MeV wide). These fluxes can be used to extract charged-current neutrino-nucleus cross sections as functions of outgoing lepton kinematics within specific neutrino energy ranges. Based on a dedicated simulation with realistic event statistics and flux-related systematic uncertainties, but assuming an almost-perfect detector, we run a feasibility study demonstrating how DUNE-PRISM data can be used to measure muon neutrino charged-current integrated and differential cross sections over narrow fluxes. We find that this approach enables a largely model-independent reconstruction of powerful observables, including energy transfer, typically accessible only in electron scattering measurements, but that large exposures may be required for differential cross section measurements with few-percentage statistical uncertainties.