Cross-sections of large-angle hadron production in proton- and pion-nucleus interactions VI: carbon nuclei and beam momenta from \pm 3 GeV/c to \pm 15 GeV/c
CDP Collaboration, A. Bolshakova, I. Boyko, G. Chelkov, D. Dedovitch, A. Elagin, D. Emelyanov, M. Gostkin, A. Guskov, Z. Kroumchtein, Y. Nefedov, K. Nikolaev, A… 展开作者
CDP Collaboration, A. Bolshakova, I. Boyko, G. Chelkov, D. Dedovitch, A. Elagin, D. Emelyanov, M. Gostkin, A. Guskov, Z. Kroumchtein, Y. Nefedov, K. Nikolaev, A. Zhemchugov, F. Dydak, J. Wotschack, A. De Min, V. Ammosov, V. Gapienko, V. Koreshev, A. Semak, Y. Sviridov, E. Usenko, V. Zaets
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% nuclear interaction length thick stationary carbon target, of proton and pion beams with momentum from \pm 3 GeV/c to \pm 15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees. Cross-sections on carbon nuclei are compared with cross-sections on beryllium, copper, tantalum and lead nuclei.
We report on double-differential inclusive cross-sections of the production of secondary protons and charged pions, in the interactions with a 5% interaction length thick stationary beryllium target, of proton and pion beams with momentum from +/-3 GeV/c to +/-15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees.
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% nuclear interaction length thick stationary copper target, of proton and pion beams with momentum from +/-3 GeV/c to +/-15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees.
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% nuclear interaction length thick stationary lead target, of proton and pion beams with momentum from +/-3 GeV/c to +/-15 GeV/c. Results are given for secondary particles with production angles 20 to 125 degrees. Cross-sections on lead nuclei are compared with cross-sections on beryllium, copper, and tantalum nuclei.
We report on double-differential inclusive cross-sections of the production of secondary protons, deuterons, and charged pions and kaons, in the interactions with a 5% nuclear interaction length thick stationary beryllium target, of a +8.9 GeV/c proton and pion beam, and a -8.0 GeV/c pion beam. Results are given for secondary particles with production angles between 20 and 125 degrees.
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% nuclear interaction length thick stationary tantalum target, of proton and pion beams with momentum from +/-3 GeV/c to +/-15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees. They are of particular relevance for the optimization of the design parameters of the proton driver of a neutrino factory.
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% nuclear interaction length thick stationary tin target, of proton and pion beams with momentum from \pm3 GeV/c to \pm15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees. Cross-sections on tin nuclei are compared with cross-sections on beryllium, carbon, copper, tantalum and lead nuclei.
We report on double-differential inclusive cross-sections of the production of secondary protons, charged pions, and deuterons, in the interactions with a 5% λint thick stationary aluminium target, of proton and pion beams with momentum from \pm3 GeV/c to \pm15 GeV/c. Results are given for secondary particles with production angles between 20 and 125 degrees. Cross-sections on aluminium nuclei are compared with cross-sections on beryllium, carbon, copper, tin, tantalum and lead nuclei.
The present study is based on the interactions caused by 340-GeV negative pions with emulsion nuclei. The main aim of this paper is to investigate some aspects of central collision events. Thus, the events in which the total number of charged shower particles is greater than or equal to twenty eight (Ns geq 28) were chosen for the analysis. They are not exactly central collision events, but may be considered as pseudo-central collision events. The angular characteristics of relativistic charged secondaries have been studied in terms of pseudo-rapidity, and bimodality is found to be absent in t…
We study coherent pion production in neutrino-nucleus scattering in the energy region relevant to neutrino oscillation experiments of current interest. Our approach is based on a combined use of the Sato-Lee model of electroweak pion production on a nucleon and the Delta-hole model of pion-nucleus reactions. Thus we develop a model which describes pion-nucleus scattering and electroweak coherent pion production in a unified manner. Numerical calculations are carried out for the case of the 12C target. All the free parameters in our model are fixed by fitting to both total and elastic different…
New data on proton and pion production in p+C interactions from the CERN PS and SPS accelerators are used in conjunction with other available data sets to perform a comprehensive survey of backward hadronic cross sections. This survey covers the complete backward hemisphere in the range of lab angles from 10 to 180 degrees, from 0.2 to 1.4 GeV/c in lab momentum and from 1 to 400 GeV/c in projectile momentum. Using the constraints of continuity and smoothness of the angular, momentum and energy dependences a consistent description of the inclusive cross sections is established which allows the …
The modelling of neutrino nucleus interactions is one of the limiting systematic errors in long base line neutrino oscillation experiments. The accurate modelling of the neutrino interactions requires more experimental observables to determine its accuracy. Adler Angles are observables carrying information about the polarization of the ?Δ resonance and the interference with the non-resonant single pion production. These observables were measured with limited statistics in bubble chamber experiments. We discuss the possibility of measuring the angles in neutrino interactions with nucleus.
We use our model for neutrino pion production on the nucleon to study pion production on a nucleus. The model is conveniently modified to include in-medium corrections and its validity is extended up to 2 GeV neutrino energies by the inclusion of new resonant contributions in the production process. Our results are compared with recent MiniBooNE data measured in mineral oil. Our total cross sections are below data for neutrino energies above 1 GeV. As with other theoretical calculations, the agreement with data improves if we neglect pion final state interaction. This is also the case for diff…
We have studied the prospects of using the Drell-Yan dilepton process in pion-nucleus collisions as a novel input in the global analysis of nuclear parton distribution functions (nPDFs). In a NLO QCD framework, we find the measured nuclear cross-section ratios from the NA3, NA10 and E615 experiments to be largely insensitive to the pion parton distributions and also compatible with the EPS09 and nCTEQ15 nPDFs. These data sets can thus be, and in EPPS16 have been, included in global nPDF analyses without introducing significant new theoretical uncertainties or tension with the other data. In pa…
We analyze the experimental data on the inclusive double differential cross section by neutrinos charged current, measured by T2K, with the same model which was successful for the MiniBooNE quasielastic cross sections. As in our previous analysis the multinucleon component is needed in order to reproduce the data. For the total cross section our evaluation is smaller than the SciBooNE data above 1 GeV. This indicates the opening of a new channel not included in our evaluation, presumably the two pion emission channel. We also check that our description holds for the exclusive single pion produ…
The energy dependence is investigated for a wide set of space-time characteristics derived from Bose - Einstein correlations of secondary pion pairs produced in proton-proton and nucleus-nucleus interactions. Analytic functions suggested for smooth approximations of the energy dependence of emission region parameters demonstrate reasonable agreement with all available experimental results for proton-proton collisions while the approximations correspond to most of experimental data for nucleus-nucleus collisions at energies above 5 GeV. Estimations for a wide set of space-time quantities are ob…
Some of the recent progress in the physics of pion production induced by neutrinos on nucleons and nuclei is reviewed from a theoretical perspective. The importance of Watson's theorem to reconcile ANL and BNL data with the off-diagonal Goldberger-Treiman relation for the $Δ(1232)$ is discussed. The disagreement between MiniBooNE data and theoretical calculations is presented in the light of the new MINERvA data. The coherent pion production data on $^{12}$C obtained by MINERvA are also compared to different microscopic and PCAC models.
Rapidity-dependent transverse momentum spectra of negatively charged pions measured at different rapidities in proton-proton collisions at the Super Proton Synchrotron (SPS) at various energies within its Beam Energy Scan (BES) program are investigated by using one- and two-component standard distributions where the chemical potential and spin property of particles are implemented. The rapidity spectra are described by a double-Gaussian distribution. At the stage of kinetic freeze-out, the event patterns are structured by the scatter plots in the three-dimensional subspaces of velocity, moment…
Despite the success of modern nuclear parton distribution functions (nPDFs) in describing nuclear hard-process data, they still suffer from large uncertainties. One of the poorly constrained features is the possible asymmetry in nuclear modifications of valence $u$ and $d$ quarks. We study the possibility of using pion-nucleus Drell-Yan dilepton data as a new constraint in the global analysis of nPDFs. We find that the nuclear cross-section ratios from the NA3, NA10 and E615 experiments can be used without imposing significant new theoretical uncertainties and, in particular, that these datase…
Transverse momentum spectra of $π^{\pm}$, $\rm K^{\pm}$ and p($\bar{\rm p}$) up to $p_{\rm T}$ = 20 GeV/$c$ at mid-rapidity in pp and Pb-Pb collisions at $\sqrt{s_{\rm NN}}=$ 2.76 TeV have been measured using the ALICE detector at the Large Hadron Collider. The proton-to-pion and the kaon-to-pion ratios both show a distinct peak at $p_{\rm T} \approx 3 GeV/c$ in central Pb-Pb collisions. Below the peak, $p_{\rm T}$ < 3 GeV/$c$, both ratios are in good agreement with hydrodynamical calculations, suggesting that the peak itself is dominantly the result of radial flow rather than anomalous hadron…
The NuSTEC workshop held at the University of Pittsburgh in October 2019 brought theorists and experimentalists together to discuss the state of modeling and measurements related to pion production in neutrino-nucleus scattering in the kinematic region where pions are produced through both resonant and non-resonant mechanisms. Modeling of this region is of critical importance to the current and future accelerator- and atmospheric-based neutrino oscillation experiments. For the benefit of the community, links to the presentations are accompanied by annotations from the speakers highlighting sig…
We apply the GiBUU model to questions relevant for current and future neutrino long-baseline experiments, we address in particular the relevance of charged-current reactions for neutrino disappearance experiments. A correct identification of charged-current quasielastic (CCQE) events - which is the signal channel in oscillation experiments - is relevant for the neutrino energy reconstruction and thus for the oscillation result. We show that about 20% of the quasielastic cross section is misidentified in present-day experiments and has to be corrected for by means of event generators. Furthermo…
The NEUT intranuclear cascade model is described and fit to a large body of \pipm--nucleus scattering data. Methods are developed to deal with deficiencies in the available historical data, and robust uncertainty estimates are produced. The results are compared to a variety of simulation packages, and the data itself. This work provides a method for tuning Final State Interaction models, which are of particular interest to neutrino experiments that operate in the few-GeV energy region, and provides results which can be used directly by the T2K and Super-Kamiokande collaborations, for whom NEUT…
The paper discusses the features of the behavior of pion production cross section as a function of the atomic mass of the target nucleus for the reaction of fragmentation of the incident deuterons in the pions produced in the so-called "twice-cumulative" kinematic region. A distinctive feature of the twice-cumulative pions is that for their production the target nucleus must be heavier than hydrogen. The simulation results show that the dependence of the cross sections for pion production in the twice-cumulative region differs from the analogous dependence for the cumulative region. The paper …
The data on production of cumulative particles in the high transverse momenta domain (up to ~ 3.5 GeV/c) in proton-nucleus interactions are presented for the first time. An indication on the local character of particle production in the cumulative domain is obtained. The observed strong dependence of the particle production cross section on the atomic mass of the target does not fit the A - dependence obtained in the pre-cumulative and cumulative domains for low transverse momenta at constant part of the exponent. The experiment was performed at U70 (IHEP) with the extracted 50 GeV/c proton be…
In neutrino-nucleus interactions, a proton produced with a correlated pion might exhibit a left-right asymmetry relative to the lepton scattering plane even when the pion is absorbed. Absent in other proton production mechanisms, such an asymmetry measured in charged-current pionless production could reveal the details of the absorbed-pion events that are otherwise inaccessible. In this study, we demonstrate the idea of using final-state proton left-right asymmetries to quantify the absorbed-pion event fraction and underlying kinematics. This technique might provide critical information that h…
I explain the Sato-Lee (SL) model and its extension to the neutrino-induced pion production off the nucleon. Then I discuss applications of the SL model to incoherent and coherent pion productions in the neutrino-nucleus scattering. I mention a further extension of this approach with a dynamical coupled-channels model developed in Excited Baryon Analysis Center of JLab.
Rescattering following a neutrino-nucleus reaction changes the number, energy, and direction of detectable hadrons. In turn, this affects the selection and kinematic distributions of subsamples of neutrino events used for interaction or oscillation analysis. This technical note focuses on three forms of two-body rescattering. Elastic hadron+nucleus scattering primarily changes the direction of the hadron with very little energy transfer. Secondly, a hadron+nucleon quasi-elastic process leads to the knockout of a single struck nucleon, possibly with charge exchange between the two hadrons. Also…
Within the impulse approximation, the modeling of the energy of final state leptons in electron and neutrino quasielastic and pion production processes on nuclear targets in the region of the $Δ$ resonance depends on several parameters. These parameters include the removal energy of the initial state nucleon from the nucleus $ε^{P,N}$, the potentials of electrons, nucleons and pions in the Coulomb field of the nucleus $|V_{eff}|$, and the kinetic energy dependent nuclear potential for final state nucleons ($U^{QE}_{opt}$) and "nucleon plus pion" final states in the region of the $Δ$ resonance …
Background: Pion production gives information on the axial form factors of nucleon resonances. It also introduces a noticeable background to quasi-elastic measurements on nuclear targets and thus has a significant impact on precision studies of neutrino oscillation parameters. Purpose: To clarify neutrino-induced pion production on nucleons and nuclei. Method: The Giessen Boltzmann--Uehling--Uhlenbeck (GiBUU) model is used for the description of neutrino-nucleus reactions. Results: Theoretical results for differential cross sections for the T2K neutrino flux at the ND280 detector and integrate…
NA61/SHINE is a fixed target experiment designed to study hadron-proton, hadron-nucleus and nucleus-nucleus interactions at the CERN Super-Proton-Synchrotron. In this proceeding we present results on spectra of identified hadrons produced in pion-carbon production interactions, which are of fundamental importance to improve the extensive air shower modeling, and hence the interpretation of ultra-high-energy-cosmic-rays measurements. In particular, our measurements of (anti)baryons and $ρ^0$ production in pion-carbon interactions can contribute to improve the predictions of muon production by a…
We evaluate $n$-particle ($n=2,3,4,5$) transverse momentum correlations for pions and kaons following from the decay of statistical clusters. These correlation functions could provide strong constraints on a possible existence of thermal clusters in the process of particle production.
We have developed a dynamical model for a unified description of the pion-nucleus scattering and photo- and neutrino-induced coherent pion production on nuclei. Our approach is based on a combined use of the Sato-Lee model for the electroweak pion production on a single nucleon and the Delta-hole model of pion-nucleus scattering. Numerical calculations are carried out for the case of the C12 target. After testing our model with the use of the pion photo-production data, we confront our predictions of the neutrino-induced coherent pion production reactions with the recent data from K2K and Mini…
[Background] Long-Baseline experiments such as T2K, NOvA or the planned Deep Underground Neutrino Experiment (DUNE) require theoretical descriptions of the complete event in a neutrino-nucleus reaction. Since nuclear targets are used this requires a good understanding of neutrino-nucleus interactions. [Purpose] One of the dominant reaction channels in neutrino-nucleus interactions is pion production. This paper aims for a coherent view on all charged current charged pion production data that are avaible from the experiments MiniBooNE, the near detector experiment at T2K and MINERvA. [Methods] …
The reaction mechanisms for neutrino interactions with an $^{40}Ar$ nucleus with the LBNF flux are calculated with the Giessen-Boltzmann-Uehling-Uhlenbeck (GiBUU) transport-theoretical implementation of these interactions. Quasielastic scattering, many-body effects, pion production and absorption and Deep Inelastic Scattering are discussed; they all play a role at the LBNF energies and are experimentally entangled with each other. Quasielastic scattering makes up for only about 1/3 of the total cross section whereas pion production channels make up about 2/3 of the total. This underlines the n…
