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At least 37 records · Page 2

Methodology of the Extraction of Multi-Differential Cross Sections of Charged-Current $\nu_\mu$-Argon Interactions in MicroBooNE Using Wire-Cell $\nu_\mu$CC Selection

Neutrino physics experiments rely on accurate nuclear-interaction models that are in part guided by experimental observations. Multi-differential cross section measurements are particularly valuable for exploring the underlying physics described in these models, making them a significant step forward in the field. This note presents methodology in preparation to unfold neutrino flux-averaged double and triple-differential cross sections of the inclusive muon neutrino charged-current interaction on Argon. This work builds upon the existing framework and methodology presented in recent energy dependent cross section measurements at MicroBooNE using the Wire-Cell tomographic event reconstruction. The signal definition, choice of binning, and handling of estimated detector uncertainties are discussed, and the MicroBooNE simulation model is validated over the multi-dimensional phase space of muon momentum, muon polar angle, and visible hadronic energy.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurement of charged-current $\nu_\mu$ and $\bar{\nu}_\mu$ cross sections on hydrocarbon in a shallow inelastic scattering region

This MINERvA analysis is the first neutrino and antineutrino study of a shallow inelastic scattering region, which is the transition region between resonant production and deep inelastic scattering processes. This transition is explicitly included in this study by expanding the scope of shallow inelastic scattering to include not only the mainly lower-$Q^2$ nonresonant pion production but also the kinematic region where pion production off quarks within the nucleon becomes significant with $Q^2$ below the onset of the deep-inelastic scattering region defined in this analysis. To reduce the resonance background the kinematic region 1.5 $<$$W$$<$ 2 GeV/$c^2$ was chosen. In addition to the inclusive differential cross section measurements, to emphasize SIS interactions off quarks within the nucleon a sample with $Q^2$$\geq$ 1 GeV/$c^2$ was also analyzed. The measurements of one-dimensional cross sections at $\left\langle E_\nu \right\rangle \sim 6$ GeV on hydrocarbon of $Q^2$, Bjorken x and muon momentum variables are compared with modified predictions from the GENIE 2 neutrino generator as well as predictions of other neutrino simulators GiBUU, NEUT, NuWro and an alternative GENIE 3 version. Significant discrepancies both in shape and magnitude between measurements and neutrino simulator predictions of all variables have been observed.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Measurements of Nuclear Effects and the $\bar \nu_\mu +H \to \mu^+ + n$ Cross Section in MINERνA with Neutron Tagging

MINERνA, or Main INjector ExpeRiment for ν-A, at Fermilab, is an experimentdedicated to the study of neutrino-nucleus interactions in the GeV regime. Itsgoal is to illustrate the interplay between hadronic and nuclear physics and measure intranuclear dynamics crucial for the present and future neutrino oscillationmeasurements. We first measure a set of variables sensitive to how Monte Carlo(MC) simulations of neutrino-nucleus interactions implement binding energy andthen move on to measure the antineutrino CCQE cross section on the hydrogentargets in MINERνA’s CH detector. We have developed a method to preferentially select events on the hydrogen by comparing outgoing neutrons’ directions totheoretical neutron directions assuming two-body interactions. We measured thecross section, extracted the axial form factor, and performed a Z-expansion fit. Weobserve larger values in the axial form factor at high Q2than current best fits. Finally, we show a preliminary selection of events with both protons and neutrons toinvestigate nuclear processes responsible for producing these final states.

Cai, Tejin↗

Measurement of $\nu_\mu/\bar\nu_\mu$ CC double-differential cross sections on MINERvA hydrocarbon target for the shallow inelastic scattering background region

Cross section measurements are essential for all neutrino oscillation experiments. In fact, uncertaintiesassociated to cross section model parameters constitute one of the dominant sources oferrors in current oscillation analyses. In particular, understanding neutrino-induced pion productionin the kinematic regime known as shallow inelastic scattering (SIS) is critical for improvingneutrino interaction modeling in event generators. In this study, 416,233 (237,468) muon neutrino(antineutrino) interactions are measured in a SIS background region, predominantly made ofbaryon resonances. The analyzed datasets were collected from 2013 to 2019, comprising neutrinosgenerated by the Fermilab NuMI facility, with mean energy of 6 GeV, and the interactions occurredon the MINERvA hydrocarbon target. The measurements are presented as double-differential crosssections in terms of the outgoing muon longitudinal and transverse momentum components, aswell as the Bjorken x and y variables. Comparisons between the extracted data and predictionsfrom several generators reveal significant discrepancies across most kinematic bins.

Souza Correia, Souza Correia, Daniel [Rio de Janei↗

A Joint Measurement of $\nu_{\mu}$-Disappearance and $\nu_{e}$e-Appearance in the NuMI beam using the NOvA Experiment

The discovery of neutrino oscillations provides the first indication of a lepton flavor violating (LFV) process, one that isn't predicted by the Standard Model. As such, NOvA is part of a rich experimental program to constrain unknown parameters in the neutrino oscillation model, described for three neutrino flavors using the PMNS unitary matrix. It is a long baseline experiment utilizing two detectors, a Near Detector at Fermilab and a Far Detector in Ash River, Minnesota for a total baseline of 810 km. It receives a predominantly ${\nu_\mu}/\overline{\bar\nu_\mu}$ beam peaking at 1:8 GeV from the NuMI beam facility at Fermilab. There are four oscillation channels used in the analysis, ${\nu_\mu} \to {\nu_\mu}$, ${\nu_\mu} \to {\nu_e}$, ${\overline{\nu}_\mu} \to {\overline{\nu}_\mu}$ and ${\overline{\nu}_\mu} \to {\overline{\nu}_e }$. With a total exposure of 13:6_10$^{20}$ and 12:5_10$^{20}$ protons on target for the neutrino and anti-neutrino beam modes respectively, 82 candidates are seen in the ${\nu_\mu} \to {\nu_e}$ channel for a total predicted backgroundof 26:8 events. Similarly, 33 candidates are seen in the corresponding anti-neutrino channel for a total predicted background of 14:0 events. In the ${\nu_\mu} \to {\nu_\mu}$ $(\overline{\nu}_\mu \to \overline{\nu}_\mu}$ channel, 211 (105) candidates are seen with an expectation of 1156.1 (488.1) events at no oscillations.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Experimental and numerical study of the intermittency exponent mu

After publication of the Kolmogorov refined similarity hypotheses, the small-scale intermittency of the energy dissipation field became a central problem in fully developed turbulence (FDT). This phenomenon has been studied in many different ways, e.g. by searching for corrections to scaling exponents in the inertial range velocity structure functions. A direct measure of this intermittency is, however, available by studying the local rate of energy dissipation, and it may be quantitatively characterized by the intermittency exponent mu. As far as we know, nobody has posed an obvious question: Is the intermittency exponent mu a unique constant, i.e., are the values mu(sub kappa), mu(sub epsilon), mu(sub r), mu(sub b), and mu(sub e) the same at high Reynolds numbers, or do they create a set of different (and perhaps independent) exponents? This paper addresses the above question using the high Reynolds number experiments.

Praskovsky, Alexander↗

Flipped SU(5) GUT phenomenology: proton decay and $\mathbf {g_\mu - 2}$

We consider proton decay and $\mathbf {g_\mu - 2}$ in flipped SU(5) GUT models. We first study scenarios in which the soft supersymmetry-breaking parameters are constrained to be universal at some high scale M in above the standard GUT scale where the QCD and electroweak SU(2) couplings unify. In this case the proton lifetime is typically > rsim10 36 years, too long to be detected in the foreseeable future, and the supersymmetric contribution to $\mathbf {g_\mu - 2}$ is too small to contribute significantly to resolving the discrepancy between the experimental measurement and data-driven calculations within the Standard Model. However, we identify a region of the constrained flipped SU(5) parameter space with large couplings between the 10- and 5-dimensional GUT Higgs representations where p → e + π 0 decay may be detectable in the Hyper-Kamiokande experiment now under construction, though the contribution to $\mathbf {g_\mu - 2}$ is still small. A substantial contribution to $\mathbf {g_\mu - 2}$ is possible, however, if the universality constraints on the soft supersymmetry-breaking masses are relaxed. We find a ‘quadrifecta’ region where observable proton decay co-exists with a (partial) supersymmetric resolution of the $\mathbf {g_\mu - 2}$ discrepancy and acceptable values of m h and the relic LSP density.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗