| |
Catala, H., Valero, E., & Rodrigo, G. (2026). Quantum computing demonstration of the polaron-molecule transition on a noisy intermediate-scale quantum device. Phys. Rev. A, 114(3), 032609–11pp.
Abstract: The simulation of strongly correlated fermionic systems remains a significant challenge in computational physics due to the exponential growth of the Hilbert space and the fermionic sign problem. In this work, we report a quantum computing demonstration exploring the unified physics of the Fermi polaron and the Bose-Einstein condensate to Bardeen-Cooper-Schrieffer crossover. We develop an effective Hamiltonian formalism that bridges pairing superfluidity and impurity physics, mapping the system onto a gate-based quantum processor via the Jordan-Wigner transformation. By utilizing a first-order Trotter-Suzuki decomposition, we implement an ancilla-controlled Ramsey interferometry protocol to resolve the system's spectral response. Our implementation captures the smooth transition from a dressed quasiparticle (polaron) regime to a stable molecular bound state, characterized by a linear energy renormalization in the strong-coupling limit. We benchmark the quantum protocol against exact diagonalization and demonstrate its execution on the Barcelona Supercomputing Center quantum hardware. To ensure reproducibility, we provide comprehensive device calibration metrics, including qubit coherence times and gate fidelities at the time of execution. Despite inherent hardware noise, the hybrid variational approach qualitatively observes the bifurcation of the spectral density.
|
|
HAWC Collaboration(Alfaro, R. et al), & Coutiño de Leon, S. (2026). HAWC Study on the Ultra-high-energy Gamma-Ray Emissions from the Pulsar Wind Nebula G32.64+0.53. Astrophys. J., 1009(1), 47–11pp.
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.
|
|
Bonatto, A. et al, & Martin-Luna, P. (2026). Laser wakefield acceleration in nanostructured plasmas. Eur. Phys. J. Plus, 141(9), 1043–10pp.
Abstract: Solid-state plasma wakefield acceleration has recently attracted attention as a novel method for achieving unprecedented ultrahigh acceleration gradients on the order of 1 TeV/m or beyond. In this context, recent advancements in nanofabrication techniques have opened up the possibility of creating structured plasmas with tailored properties. For instance, the utilization of carbon nanotube (CNT) bundles holds great potential for generating stable plasmas with electron densities reaching as high as 1022 cm-3 , i.e., orders of magnitude higher than conventional gaseous plasmas. As part of a new collaborative effort called NanoAc, we have conducted particle-in-cell (PIC) simulations to investigate laser wakefield acceleration in nanostructured solid-state plasmas based on CNT arrays. Our results confirm the attainment of wakefields at the TV/m scale. Additionally, we observed self-injection, sub-femtosecond bunch formation, and electron acceleration in micrometer-scale targets, yielding kinetic energies on the order of a few tens of MeV. These findings open up promising possibilities to design novel ultracompact accelerators and radiation sources. In this paper, we report recent simulation results from the NanoAc collaboration and describe ongoing efforts toward future experimental tests at available laser facilities.
|
|
Gutierrez Arance, H., Carrio, F., Fiorini, L., Folgueras, S., Hervas Alvarez, F., Leguina Lppez, P., et al. (2026). FPGA acceleration of matrix-element calculations for Monte Carlo event generation. Comput. Phys. Commun., 329, 110394–16pp.
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.
|
|
Mandal, S., Roshan, R., & Valle, J. W. F. (2026). Particle and gravitational wave probes of minimal seesaw neutrinos. J. High Energy Phys., 09(9), 173–30pp.
Abstract: Observable gravitational waves (GWs) from first-order phase transitions (FOPTs) can coexist with distinct particle physics signatures. These include same-sign dilepton plus four jet events at colliders, such as e + e -/mu + μ- -> & ell; +/- & ell; +/- 4j, neutrinoless double beta decay, as well as charged lepton flavor violating (cLFV) processes such as μ-> e gamma. We explore this synergy within the minimal low-scale linear seesaw model. This framework successfully reproduces neutrino oscillation data, providing a direct avenue to probe the neutrino mass ordering and Majorana nature at colliders. Crucially, the FOPT responsible for the GW background is driven by a leptophilic Higgs doublet, establishing a direct link between early-universe cosmology and terrestrial laboratory experiments.
|
|
|
