arXiv subjects

Federico Sanchez

Publications and source records attributed to Federico Sanchez.

13 recordsLinked to original sources

arXiv2026

Flux jump correction in the QUBIC TES data pipeline

Flux jumps occur in the readout electronics of Transition Edge Sensor (TES) detectors coupled to Superconducting Quantum Interference Devices (SQUIDs), as a consequence of the periodic transfer function of SQUIDs in the superconducting regime. These events manifest as discontinuities in the Time Ordered Data (TOD) and can significantly degrade the quality of the measured signals. In this work, we present an automated pipeline to identify and correct flux jumps in the calibration data of the QUBIC (Q \& U Bolometric Interferometer for Cosmology) instrument, designed to measure the B-mode polarization of the Cosmic Microwave Background (CMB). Using data from multiple observation campaigns, we characterize the statistical properties of flux jumps and compare them with expectations based on the electronic configuration of the instrument. The proposed pipeline successfully corrects these events, allowing the recovery of affected data and enabling their use in subsequent CMB analysis.

astro-ph.IM↗

arXiv2026

A generalized likelihood model for segmented muon counters

Measurements of the muonic component of extensive air showers constrain cosmic-ray mass composition and hadronic interactions at energies beyond those accessible at accelerators. Arrays of segmented detectors with binary readout are widely used for this purpose: they sample the muon density at different distances from the shower core to reconstruct the muon lateral distribution function (LDF). Each detector response is summarized by the number of activated segments, $k$, whose probability distribution provides the likelihood relating the observation to the expected muon content. Signal pile-up, detector inefficiency, corner-clipping muons, and background signals shape this distribution, and neglecting them can bias the reconstruction. Existing analytical models include pile-up but otherwise assume an ideal detector response. In this work, we develop a unified statistical framework that incorporates inefficiency, corner clipping, and background through a small set of physically interpretable parameters. We derive exact expressions for the detector response and the likelihood required for muon-LDF reconstruction, together with a simple binomial approximation that preserves the main statistical properties of the exact distribution. Dedicated Monte Carlo simulations are used to assess the impact of the assumptions underlying the analytical treatment and show that it is negligible over the parameter range considered. They also show that the exact and approximate likelihoods yield similar performance in terms of estimator bias and confidence-interval coverage. Although motivated by the Underground Muon Detector of the Pierre Auger Observatory, the framework applies more broadly to segmented particle detectors with binary readout in which particle content is inferred from the number of activated segments.

astro-ph.IM↗

arXiv2026

Azimuthal asymmetry in exclusive quasi-elastic neutrino-nucleus interactions

In neutrino oscillation experiments, exclusive measurements of neutrino-nucleus interactions play a critical role, by providing the theoretical and experimental input needed for a reliable estimation of the neutrino energy. In this paper, we derive the general form of the azimuthal angle distribution for quasi-elastic scattering, focusing on a dependency that has been routinely overlooked. We demonstrate that the outgoing nucleon exhibits a preference for emission outside the lepton scattering plane, with an asymmetric azimuthal distribution. In the context of neutrino-nucleus scattering, we argue that this asymmetry is caused by parity violation in the weak interaction. Furthermore, we show that in cross section calculations the asymmetry is sensitive to nuclear modeling choices and to the shell structure of the initial nucleus, thus providing a novel source of information for energy reconstruction in neutrino experiments. We study the experimental feasibility of observing this effect by applying a realistic momentum detection threshold and an intranuclear cascade. We estimate that the asymmetry is observable with $\mathcal{O}$($10^4$) events at the 99% confidence level for neutrino interactions on $^{12}$C, suggesting that the effect is within reach of the current generation of neutrino detectors.

nucl-th↗

arXiv2025

Characterisation of the Bedretto Underground Site for Fundamental Physics Experiments

Underground laboratories provide the ultra-low background and low-vibration environments essential for rare-event searches, gravitational-wave detection, and quantum-sensing technologies. We report a comprehensive environmental characterisation of the Bedretto tunnel in Ticino, Switzerland, a site offering horizontal access, excellent infrastructure, and the potential to be be Europe's second-deepest and quietest underground laboratory. At the prospective physics site, located beneath an overburden exceeding 1400 m, we measure the cosmic-muon, gamma-ray, and neutron fluxes, as well as the radon concentration, magnetic-field spectrum, and seismic backgrounds. The muon flux is suppressed by six orders of magnitude relative to the surface, consistent with an effective depth of about 4000 metre water equivalent, gamma-ray and neutron measurements reflect the local geology and guide shielding requirements for future particle and nuclear physics experiments. Magnetic and seismic noise levels are found to be exceptionally low, meeting or exceeding the criteria for next-generation atom-interferometric gravitational-wave detectors. These results establish the site as a highly competitive, accessible deep-underground location for fundamental-physics experiments.

astro-ph.IM↗

arXiv2025

Optimizing HERON for 100 PeV Neutrino Detection

The Hybrid Elevated Radio Observatory for Neutrinos (HERON) is designed to target the astrophysical flux of Earth-skimming tau neutrinos at 100 PeV. HERON consists of multiple compact, phased radio arrays embedded within a larger sparse array of antennas, located on the side of a mountain. This hybrid design provides both excellent sensitivity and a sub-degree pointing resolution. To design HERON, a suite of simulations accounting for tau propagation, shower development, radio emission, and antenna response were used. These simulations were used to discover the array layout which provides maximum sensitivity at 100 PeV, as well to select the optimal antenna design. Additionally, the event reconstruction accuracy has been tested for various designs of the sparse array via simulated interferometry. Here, we present the HERON simulation procedure and its results.

astro-ph.IM↗

arXiv2025

The Hybrid Elevated Radio Observatory for Neutrinos (HERON) Project

Measuring ultra-high energy neutrinos, with energies above $10^{16}$ eV, is the next frontier of the emerging multi-messenger era. Their detection requires building a large-scale detector with 10 times the instantaneous sensitivity of current instruments, sub-degree angular resolution, and wide daily field of view. The Hybrid Elevated Radio Observatory for Neutrinos (HERON) is designed to be that discovery instrument. HERON combines the complementary features of two radio techniques being demonstrated by the BEACON and GRAND prototypes. Its preliminary design consists of 24 compact, elevated phased stations with 24 antennas each, embedded in a sparse array of 360 standalone antennas. This setup tunes the energy threshold to below 100 PeV, where the neutrino flux should be high. The sensitivity of the phased stations combines with the powerful reconstruction capacities of the standalone antennas to produce an optimal detector. HERON is planned to be installed at an elevation of 1,000 m across a 72 km-long mountain range overlooking a valley in Argentina's San Juan province. It would be connected to the worldwide network of multimessenger observatories and search for neutrino bursts from candidate sources of cosmic rays, like gamma-ray bursts and other powerful transients. With HERON's deep sensitivity, this strategy targets discoveries that cast new light into the inner workings of the most violent astrophysical sources at uncharted energies. We present the preliminary design, performances, and observation strategy of HERON.

astro-ph.IM↗

arXiv2022

Quantum computing of the $^6$Li nucleus via ordered unitary coupled clusters

The variational quantum eigensolver (VQE) is an algorithm to compute ground and excited state energy of quantum many-body systems. A key component of the algorithm and an active research area is the construction of a parametrized trial wavefunction -- a so called variational ansatz. The wavefunction parametrization should be expressive enough, i.e. represent the true eigenstate of a quantum system for some choice of parameter values. On the other hand, it should be trainable, i.e. the number of parameters should not grow exponentially with the size of the system. Here, we apply VQE to the problem of finding ground and excited state energies of the odd-odd nucleus $^6$Li. We study the effects of ordering fermionic excitation operators in the unitary coupled clusters ansatz on the VQE algorithm convergence by using only operators preserving the $J_z$ quantum number. The accuracy is improved by two order of magnitude in the case of descending order. We first compute optimal ansatz parameter values using a classical state-vector simulator with arbitrary measurement accuracy and then use those values to evaluate energy eigenstates of $^6$Li on a superconducting quantum chip from IBM. We post-process the results by using error mitigation techniques and are able to reproduce the exact energy with an error of 3.8% and 0.1% for the ground state and for the first excited state of $^6$Li, respectively.

nucl-th↗

arXiv2021

Inclusive and exclusive neutrino-nucleus cross sections and the reconstruction of the interaction kinematics

We present a full kinematic analysis of neutrino-nucleus charged current quasielastic interactions based on the Local Fermi Gas model and the Random PhaseApproximation. The model was implemented in the NEUT Monte Carlo framework, which allows us to investigate potentially measurable observables, including hadron distributions. We compare the predictions simultaneously to the most recent T2K and MINERvA charged current (CC) inclusive, CC0$π$ and transverse kinematic-imbalance variable results. We pursuit a microscopic interpretation of the relevant reaction mechanisms, with the aim of achieving in neutrino oscillation experiments a correct reconstruction of the incoming neutrino kinematics, free of conceptual biasses. Such study is of the utmost importance for the ambitious experimental program which is underway to precisely determine neutrino properties, test the three-generation paradigm, establish the order of mass eigenstates and investigate leptonic CP violation.

hep-ph↗

arXiv2019

Research and Development for Near Detector Systems Towards Long Term Evolution of Ultra-precise Long-baseline Neutrino Experiments

With the discovery of non-zero value of $θ_{13}$ mixing angle, the next generation of long-baseline neutrino (LBN) experiments offers the possibility of obtaining statistically significant samples of muon and electron neutrinos and anti-neutrinos with large oscillation effects. In this document we intend to highlight the importance of Near Detector facilities in LBN experiments to both constrain the systematic uncertainties affecting oscillation analyses but also to perform, thanks to their close location, measurements of broad benefit for LBN physics goals. A strong European contribution to these efforts is possible.

physics.ins-det↗

arXiv2013

A new concept of y-ray telescope. LArGO: Liquid Argon Gamma-ray Observatory

LArGO (Liquid Argon Gamma-ray Observatory) consists of a new design for a $γ$-ray telescope, which exploits the idea of using a Liquid Argon Time Projection Chamber (LAr-TPC) as tracker-converter. Particle tracking in LAr-TPC can efficiently starts since the primary photon vertex. Indeed, while in the present space telescopes the incident photon converts in a tungsten foil, which is a passive material, in a LAr-TPC this conversion happens in LAr itself, which is fully active. In this proceeding is described a plausible design for the tracker-converter detector which fulfills the constraints on conversion efficiency, angular resolution, and wide field of view. It is demonstrated how this design can provide an unprecedented angular resolution for a $γ$-ray telescope, leading to a significant improvement in sensitivity and most important disclosing the possibility to detect the polarization of $γ$-ray emission.

astro-ph.IM↗

arXiv2005

The shower size parameter as estimator of extensive air shower energy in fluorescence telescopes

The fluorescence technique has been successfully used to detect ultrahigh energy cosmic rays by indirect measurements. The underlying idea is that the number of charged particles in the atmospheric shower, i.e, its longitudinal profile, can be extracted from the amount of emitted nitrogen fluorescence light. However the influence of shower fluctuations and the very possible presence of different nuclear species in the primary cosmic ray spectrum makes the estimate of the shower energy from the fluorescence data analysis a difficult task. We investigate the potential of shower size at maximum depth as estimator of shower energy. The detection of the fluorescence light is simulated in detail and the reconstruction biases are carefully analyzed. We extend our calculations to both HiRes and EUSO experiments. This approach has shown some advantages to the reconstruction of the energy when compared to the standard analysis procedure.

astro-ph↗

arXiv2005

Analysis of shower size as estimator of extensive air shower energy

The fluorescence technique has been successfully used to detect ultrahigh energy cosmic rays by indirect measurements. The underlying idea is that the number of charged particles in the atmospheric shower, i.e, its longitudinal profile, can be extracted from the amount of emitted nitrogen fluorescence light. However the influence of shower fluctuations and the very possible presence of different nuclear species in the primary cosmic ray spectrum make the estimate of the shower energy from the fluorescence data analysis a difficult task. We investigate the potential of shower size at maximum depth as estimator of shower energy. The detection of the fluorescence light is simulated in detail and the reconstruction biases are carefully analyzed. We extend our calculations to both Auger and EUSO experiments. This kind of approach is of particular interest for showers that are not fully contained inside the field of view of the detector.

astro-ph↗

arXiv2002

Lensing of ultra-high energy cosmic rays in turbulent magnetic fields

We consider the propagation of ultra high energy cosmic rays through turbulent magnetic fields and study the transition between the regimes of single and multiple images of point-like sources. The transition occurs at energies around $E_c\simeq Z~41 {\rm EeV}(B_{rms}/5 μ{\rm G}) (L/ 2 {\rm kpc})^{3/2}\sqrt{50 {\rm pc}/L_c}$, where $L$ is the distance traversed by the CR's with electric charge $Ze$ in the turbulent magnetic field of root mean square strength $B_{rms}$ and coherence length $L_c$. We find that above $2 E_c$ only sources located in a fraction of a few % of the sky can reach large amplifications of its principal image or start developing multiple images. New images appear in pairs with huge magnifications, and they remain amplified over a significant range of energies. At decreasing energies the fraction of the sky in which sources can develop multiple images increases, reaching about 50% for $E>E_c/2$. The magnification peaks become however increasingly narrower and for $E<E_c/3$ their integrated effect becomes less noticeable. If a uniform magnetic field component is also present it would further narrow down the peaks, shrinking the energy range in which they can be relevant. Below $E\simeq E_c/10$ some kind of scintillation regime is reached, where many demagnified images of a source are present but with overall total magnification of order unity. We also search for lensing signatures in the AGASA data studying two-dimensional correlations in angle and energy and find some interesting hints.

astro-ph↗