arXiv subjects

M. G. Catanesi

Publications and source records attributed to M. G. Catanesi.

At least 91 records · Page 5Linked to original sources

arXiv2020

Measurement of the charged-current electron (anti-)neutrino inclusive cross-sections at the T2K off-axis near detector ND280

The electron (anti-)neutrino component of the T2K neutrino beam constitutes the largest background in the measurement of electron (anti-)neutrino appearance at the far detector. The electron neutrino scattering is measured directly with the T2K off-axis near detector, ND280. The selection of the electron (anti-)neutrino events in the plastic scintillator target from both neutrino and anti-neutrino mode beams is discussed in this paper. The flux integrated single differential charged-current inclusive electron (anti-)neutrino cross-sections, $dσ/dp$ and $dσ/d\cos(θ)$, and the total cross-sections in a limited phase-space in momentum and scattering angle ($p > 300$ MeV/c and $θ\leq 45^{\circ}$) are measured using a binned maximum likelihood fit and compared to the neutrino Monte Carlo generator predictions, resulting in good agreement.

hep-ex↗

arXiv2020

T2K ND280 Upgrade -- Technical Design Report

In this document, we present the Technical Design Report of the Upgrade of the T2K Near Detector ND280. The goal of this upgrade is to improve the Near Detector performance to measure the neutrino interaction rate and to constrain the neutrino interaction cross-sections so that the uncertainty in the number of predicted events at Super-Kamiokande is reduced to about 4%. This will allow to improve the physics reach of the T2K-II project. This goal is achieved by modifying the upstream part of the detector, adding a new highly granular scintillator detector (Super-FGD), two new TPCs (High-Angle TPC) and six TOF planes. Details about the detector concepts, design and construction methods are presented, as well as a first look at the test-beam data taken in Summer 2018. An update of the physics studies is also presented.

physics.ins-det↗

arXiv2020

The Hyper-Kamiokande Experiment -- Snowmass LOI

Hyper-Kamiokande is the next generation underground water Cherenkov detector that builds on the highly successful Super-Kamiokande experiment. The detector which has an 8.4~times larger effective volume than its predecessor will be located along the T2K neutrino beamline and utilize an upgraded J-PARC beam with 2.6~times beam power. Hyper-K's low energy threshold combined with the very large fiducial volume make the detector unique, that is expected to acquire an unprecedented exposure of 3.8~Mton$\cdot$year over a period of 20~years of operation. Hyper-Kamiokande combines an extremely diverse science program including nucleon decays, long-baseline neutrino oscillations, atmospheric neutrinos, and neutrinos from astrophysical origins. The scientific scope of this program is highly complementary to liquid-argon detectors for example in sensitivity to nucleon decay channels or supernova detection modes. Hyper-Kamiokande construction has started in early 2020 and the experiment is expected to start operations in 2027. The Hyper-Kamiokande collaboration is presently being formed amongst groups from 19 countries including the United States, whose community has a long history of making significant contributions to the neutrino physics program in Japan. US physicists have played leading roles in the Kamiokande, Super-Kamiokande, EGADS, K2K, and T2K programs.

physics.ins-det↗

arXiv2020

Simultaneous measurement of the muon neutrino charged-current cross section on oxygen and carbon without pions in the final state at T2K

This paper reports the first simultaneous measurement of the double differential muon neutrino charged-current cross section on oxygen and carbon without pions in the final state as a function of the outgoing muon kinematics, made at the ND280 off-axis near detector of the T2K experiment. The ratio of the oxygen and carbon cross sections is also provided to help validate various models' ability to extrapolate between carbon and oxygen nuclear targets, as is required in T2K oscillation analyses. The data are taken using a neutrino beam with an energy spectrum peaked at 0.6 GeV. The extracted measurement is compared with the prediction from different Monte Carlo neutrino-nucleus interaction event generators, showing particular model separation for very forward-going muons. Overall, of the models tested, the result is best described using Local Fermi Gas descriptions of the nuclear ground state with RPA suppression.

hep-ex↗

arXiv2020

The ENUBET positron tagger prototype: construction and testbeam performance

A prototype for the instrumented decay tunnel of ENUBET was tested in 2018 at the CERN East Area facility with charged particles up to 5 GeV. This detector is a longitudinal sampling calorimeter with lateral scintillation light readout. The calorimeter was equipped by an additional "$t_0$-layer" for timing and photon discrimination. The performance of this detector in terms of electron energy resolution, linearity, response to muons and hadron showers are presented in this paper and compared with simulation. The $t_0$-layer was studied both in standalone mode using pion charge exchange and in combined mode with the calorimeter to assess the light yield and the 1 mip/2 mip separation capability. We demonstrate that this system fulfills the requirements for neutrino physics applications and discuss performance and additional improvements.

physics.ins-det↗

arXiv2020

First combined measurement of the muon neutrino and antineutrino charged-current cross section without pions in the final state at T2K

This paper presents the first combined measurement of the double-differential muon neutrino and antineutrino charged-current cross sections with no pions in the final state on hydrocarbon at the off-axis near detector of the T2K experiment. The data analyzed in this work comprise 5.8$\times$10$^{20}$ and 6.3$\times$10$^{20}$ protons on target in neutrino and antineutrino mode respectively, at a beam energy peak of 0.6 GeV. Using the two measured cross sections, the sum, difference and asymmetry were calculated with the aim of better understanding the nuclear effects involved in such interactions. The extracted measurements have been compared with the prediction from different Monte Carlo generators and theoretical models showing that the difference between the two cross sections have interesting sensitivity to nuclear effects.

hep-ex↗

arXiv2020

Measurements of $\barν_μ$ and $\barν_μ + ν_μ$ charged-current cross-sections without detected pions nor protons on water and hydrocarbon at mean antineutrino energy of 0.86 GeV

We report measurements of the flux-integrated $\barν_μ$ and $\barν_μ+ν_μ$ charged-current cross-sections on water and hydrocarbon targets using the T2K anti-neutrino beam, with a mean neutrino energy of 0.86 GeV. The signal is defined as the (anti-)neutrino charged-current interaction with one induced $μ^\pm$ and no detected charged pion nor proton. These measurements are performed using a new WAGASCI module recently added to the T2K setup in combination with the INGRID Proton module. The phase space of muons is restricted to the high-detection efficiency region, $p_μ>400~{\rm MeV}/c$ and $θ_μ<30^{\circ}$, in the laboratory frame. Absence of pions and protons in the detectable phase space of "$p_π>200~{\rm MeV}/c$ and $θ_π<70^{\circ}$", and "$p_{\rm p}>600~{\rm MeV}/c$ and $θ_{\rm p}<70^{\circ}$" is required. In this paper, both of the $\barν_μ$ cross-sections and $\barν_μ+ν_μ$ cross-sections on water and hydrocarbon targets, and their ratios are provided by using D'Agostini unfolding method. The results of the integrated $\barν_μ$ cross-section measurements over this phase space are $σ_{\rm H_{2}O}\,=\,(1.082\pm0.068(\rm stat.)^{+0.145}_{-0.128}(\rm syst.)) \times 10^{-39}~{\rm cm^{2}/nucleon}$, $σ_{\rm CH}\,=\,(1.096\pm0.054(\rm stat.)^{+0.132}_{-0.117}(\rm syst.)) \times 10^{-39}~{\rm cm^{2}/nucleon}$, and $σ_{\rm H_{2}O}/σ_{\rm CH} = 0.987\pm0.078(\rm stat.)^{+0.093}_{-0.090}(\rm syst.)$. The $\barν_μ+ν_μ$ cross-section is $σ_{\rm H_{2}O} = (1.155\pm0.064(\rm stat.)^{+0.148}_{-0.129}(\rm syst.)) \times 10^{-39}~{\rm cm^{2}/nucleon}$, $σ_{\rm CH}\,=\,(1.159\pm0.049(\rm stat.)^{+0.129}_{-0.115}(\rm syst.)) \times 10^{-39}~{\rm cm^{2}/nucleon}$, and $σ_{\rm H_{2}O}/σ_{\rm CH}\,=\,0.996\pm0.069(\rm stat.)^{+0.083}_{-0.078}(\rm syst.)$.

hep-ex↗

arXiv2020

Search for heavy neutrinos with the T2K near detector ND280

This paper reports on the search for heavy neutrinos with masses in the range $140 < M_N < 493$ MeV/c$^2$ using the off-axis near detector ND280 of the T2K experiment. These particles can be produced from kaon decays in the standard neutrino beam and then subsequently decay in ND280. The decay modes under consideration are $N \to \ell^{\pm}_α π^{\mp}$ and $N \to \ell^+_α \ell^-_β ν(\barν)$ ($α,β=e,μ$). A search for such events has been made using the Time Projection Chambers of ND280, where the background has been reduced to less than two events in the current dataset in all channels. No excess has been observed in the signal region. A combined Bayesian statistical approach has been applied to extract upper limits on the mixing elements of heavy neutrinos to electron-, muon- and tau- flavoured currents ($U_e^2$, $U_μ^2$, $U_τ^2$) as a function of the heavy neutrino mass, e.g. $U_e^2 < 10^{-9}$ at $90\%$ C.L. for a mass of $390$ MeV/c$^2$. These constraints are competitive with previous experiments.

hep-ex↗

arXiv2020

Decay tunnel instrumentation for the ENUBET neutrino beam

The uncertainty in the initial neutrino flux is the main limitation for a precise determination of the absolute neutrino cross section. The ERC funded ENUBET project (2016-2021) is studying a facility based on a narrow band beam to produce an intense source of electron neutrinos with a ten-fold improvement in accuracy. Since March 2019 ENUBET is also a Neutrino Platform experiment at CERN: NP06/ENUBET. A key element of the project is the instrumentation of the decay tunnel to monitor large angle positrons produced together with $ν_e$ in the three body decays of kaons ($K_{e3}$) and to discriminate them from neutral and charged pions. The need for an efficient and high purity e/$π$ separation over a length of several meters, and the requirements for fast response and radiation hardness imposed by the harsh beam environment, suggested the implementation of a longitudinally segmented Fe/scintillator calorimeter with a readout based on WLS fibers and SiPM detectors. An extensive experimental program through several test beam campaigns at the CERN-PS T9 beam line has been pursued on calorimeter prototypes, both with a shashlik and a lateral readout configuration. The latter, in which fibers collect the light from the side of the scintillator tiles, allows to place the light sensors away from the core of the calorimeter, thus reducing possible irradiation damages with respect to the shashlik design. This contribution will present the achievements of the prototyping activities carried out, together with irradiation tests made on the Silicon Photo-Multipliers. The results achieved so far pin down the technology of choice for the construction of the 3 m long demonstrator that will take data in 2021.

physics.ins-det↗

arXiv2020

Search for proton decay into three charged leptons in 0.37 megaton-years exposure of the Super-Kamiokande

A search for proton decay into three charged leptons has been performed by using 0.37$\,$Mton$\cdot$years of data collected in Super-Kamiokande. All possible combinations of electrons, muons and their anti-particles consistent with charge conservation were considered as decay modes. No significant excess of events has been found over the background, and lower limits on the proton lifetime divided by the branching ratio have been obtained. The limits range between $9.2\times10^{33}$ to $3.4\times10^{34}$ years at 90$\,$% confidence level, improving by more than an order of magnitude upon limits from previous experiments. A first limit has been set for the $p\rightarrowμ^-e^+e^+$ mode.

hep-ex↗

arXiv2020

Polysiloxane-based scintillators for shashlik calorimeters

We present the first application of polysiloxane-based scintillators as active medium in a shashlik sampling calorimeter. These results were obtained from a testbeam campaign of a $\sim$6$\times$6$\times$45 cm$^3$ (13 $X_0$ depth) prototype. A Wavelength Shifting fiber array of 36 elements runs perpendicularly to the stack of iron (15 mm) and polysiloxane scintillator (15 mm) tiles with a density of about one over cm$^2$. Unlike shashlik calorimeters based on plastic organic scintillators, here fibers are optically matched with the scintillator without any intermediate air gap. The prototype features a compact light readout based on Silicon Photo-Multipliers embedded in the bulk of the detector. The detector was tested with electrons, pions and muons with energies ranging from 1 to 7 GeV at the CERN-PS. This solution offers a highly radiation hard detector to instrument the decay region of a neutrino beam, providing an event-by-event measurement of high-angle decay products associated with neutrino production (ENUBET, Enhanced NeUtrino BEams from kaon Tagging, ERC project). The results in terms of light yield, uniformity and energy resolution, are compared to a similar calorimeter built with ordinary plastic scintillators.

physics.ins-det↗

arXiv2019

Performances of a resistive MicroMegas module for the Time Projection Chambers of the T2K Near Detector upgrade

An upgrade of the Near Detector of the T2K long baseline neutrino oscillation experiment, ND280, has been proposed. This upgrade will include two new Time Projection Chambers, each equipped with 16 resistive MicroMegas modules for gas amplification. A first prototype of resistive MicroMegas has been designed, built, installed in the HARP field cage, and exposed to a beam of charged particles at CERN. The data have been used to characterize the performances of the resistive MicroMegas module. A spatial resolution of 300 $μm$ and a deposited energy resolution of 9% were observed for horizontal electrons crossing the TPCs at 30 cm from the anode. Such performances fully satisfy the requirements for the upgrade of the ND280 TPC.

physics.ins-det↗

arXiv2019

Measurement of neutrino and antineutrino neutral-current quasielastic-like interactions on oxygen by detecting nuclear de-excitation $γ$-rays

Neutrino- and antineutrino-oxygen neutral-current quasielastic-like interactions are measured at Super-Kamiokande using nuclear de-excitation $γ$-rays to identify signal-like interactions in data from a $14.94 \ (16.35)\times 10^{20}$ protons-on-target exposure of the T2K neutrino (antineutrino) beam. The measured flux-averaged cross sections on oxygen nuclei are $\langle σ_{ν{\rm -NCQE}} \rangle = 1.70 \pm 0.17 ({\rm stat.}) ^{+ {\rm 0.51}}_{- {\rm 0.38}} ({\rm syst.}) \times 10^{-38} \ {\rm cm^2/oxygen}$ with a flux-averaged energy of 0.82 GeV and $\langle σ_{\barν {\rm -NCQE}} \rangle = 0.98 \pm 0.16 ({\rm stat.}) ^{+ {\rm 0.26}}_{- {\rm 0.19}} ({\rm syst.}) \times 10^{-38} \ {\rm cm^2/oxygen}$ with a flux-averaged energy of 0.68 GeV, for neutrinos and antineutrinos, respectively. These results are the most precise to date, and the antineutrino result is the first cross section measurement of this channel. They are compared with various theoretical predictions. The impact on evaluation of backgrounds to searches for supernova relic neutrinos at present and future water Cherenkov detectors is also discussed.

hep-ex↗

arXiv2019

Search for Astronomical Neutrinos from Blazar TXS0506+056 in Super-Kamiokande

We report a search for astronomical neutrinos in the energy region from several GeV to TeV in the direction of the blazar TXS0506+056 using the Super-Kamiokande detector following the detection of a 100 TeV neutrino from the same location by the IceCube collaboration. Using Super-Kamiokande neutrino data across several data samples observed from April 1996 to February 2018 we have searched for both a total excess above known backgrounds across the entire period as well as localized excesses on smaller time scales in that interval. No significant excess nor significant variation in the observed event rate are found in the blazar direction. Upper limits are placed on the electron and muon neutrino fluxes at 90\% confidence level as $6.03 \times 10^{-7}$ and $4.52 \times 10^{-7}$ to $9.26 \times 10^{-10}$ [${\rm erg}/{\rm cm}^2/{\rm s}$], respectively.

astro-ph.HE↗

arXiv2019

Search for Electron Antineutrino Appearance in a Long-baseline Muon Antineutrino Beam

Electron antineutrino appearance is measured by the T2K experiment in an accelerator-produced antineutrino beam, using additional neutrino beam operation to constrain parameters of the PMNS mixing matrix. T2K observes 15 candidate electron antineutrino events with a background expectation of 9.3 events. Including information from the kinematic distribution of observed events, the hypothesis of no electron antineutrino appearance is disfavored with a significance of 2.40σ and no discrepancy between data and PMNS predictions is found. A complementary analysis that introduces an additional free parameter which allows non-PMNS values of electron neutrino and antineutrino appearance also finds no discrepancy between data and PMNS predictions.

hep-ex↗

arXiv2019

Sensitivity of Super-Kamiokande with Gadolinium to Low Energy Anti-neutrinos from Pre-supernova Emission

Supernova detection is a major objective of the Super-Kamiokande (SK) experiment. In the next stage of SK (SK-Gd), gadolinium (Gd) sulfate will be added to the detector, which will improve the ability of the detector to identify neutrons. A core-collapse supernova will be preceded by an increasing flux of neutrinos and anti-neutrinos, from thermal and weak nuclear processes in the star, over a timescale of hours; some of which may be detected at SK-Gd. This could provide an early warning of an imminent core-collapse supernova, hours earlier than the detection of the neutrinos from core collapse. Electron anti-neutrino detection will rely on inverse beta decay events below the usual analysis energy threshold of SK, so Gd loading is vital to reduce backgrounds while maximising detection efficiency. Assuming normal neutrino mass ordering, more than 200 events could be detected in the final 12 hours before core collapse for a 15-25 solar mass star at around 200 pc, which is representative of the nearest red supergiant to Earth, $\mathrmα$Ori (Betelgeuse). At a statistical false alarm rate of 1 per century, detection could be up to 10 hours before core collapse, and a pre-supernova star could be detected by SK-Gd up to 600 pc away. A pre-supernova alert could be provided to the astrophysics community following gadolinium loading.

astro-ph.HE↗

arXiv2019

Measurement of the muon neutrino charged-current single $π^+$ production on hydrocarbon using the T2K off-axis near detector ND280

We report the measurements of single and double differential cross section of muon neutrino charged-current interactions on carbon with a single positively charged pion in the final state at the T2K off-axis near detector using $5.56\times10^{20}$ protons on target. The analysis uses data control samples for the background subtraction and the cross section signal, defined as a single negatively charged muon and a single positively charged pion exiting from the target nucleus, is extracted using an unfolding method. The model dependent cross section, integrated over the T2K off-axis neutrino beam spectrum peaking at $0.6$~GeV, is measured to be $σ= (11.76 \pm 0.44 \text{(stat)} \pm 2.39 \text{(syst)}) \times 10^{-40} \text{cm}^2$~$\text{nucleon}^{-1}$. Various differential cross sections are measured, including the first measurement of the Adler angles for single charged pion production in neutrino interactions with heavy nuclei target.

hep-ex↗

arXiv2019

First Measurement of the Charged Current $\overlineν_μ$ Double Differential Cross Section on a Water Target without Pions in the final state

This paper reports the first differential measurement of the charged-current $\overlineν_μ$ interaction cross section on water with no pions in the final state. The unfolded flux-averaged measurement using the T2K off-axis near detector is given in double differential bins of $μ^+$ momentum and angle. The integrated cross section in a restricted phase space is $σ=\left(1.11\pm0.18\right)\times10^{-38}$ cm$^{2}$ per water molecule. Comparisons with several nuclear models are also presented.

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