PoS(ICHEP2020)182 , , b , j , c a , c e , o , e , G. Sirri , E. Conti j k , , , k https://pos.sissa.it/ k , k j , j , A. Gola , , L. Votano , V. Mascagna u u m , M. Pozzato c c , A. Paoloni , C. Scian p m , A. Branca , G. Collazuol , A. Longhin b , M. Vesco c k , j m , L. Patrizii , S. Carturan o , B. Goddard , A. Margotti b c h , , a b , M. Nessi j , A. C. Ruggeri q , F. Velotti , , F. Cindolo i p , M. Bonesini m , M. Laveder b r , a , S. Capelli m , A. Falcone , G. Mandrioli l q , , G. Paternoster , M. Mezzetto p g , s c , C. Riccio l , E. Vallazza h , b , Y. Kudenko t , G. Ballerini o , M. Calviani , N. Charitonidis k c , L. Magaletti , j b , G. De Rosa , a k , j , L. Pasqualini , M. Torti , A. Meregaglia c h m , , E. Radicioni , b e b , B. Klicek m and F. Acerbi , S. Cecchini , G. Brunetti l ∗ h , , C. Delogu , M. Tenti E, j b t , E. Lutsenko f , F. Pupilli , V. Kein s b , L. Meazza , , , E. Parozzi c j a d , k CERN, Geneva, Switzerland. Phys. Dep. Università di Padova, Padova, Italy. Phys. Dep. Università La Sapienza, Rome,Fondazione Italy. Bruno Kessler (FBK) and INFNINFN, TIFPA, Sezione Trento, Italy. di Napoli, Napoli, Italy. Phys. Dep. Università degli Studi di Napoli Federico II, Napoli, Italy. INFN, Sezione di Milano-Bicocca, Milano, Italy. IPHC, Université de Strasbourg, CNRS/IN2P3, Strasbourg, France. Phys. Dep. Università di Bologna, Bologna,Phys. Italy. Dep. Università di Milano-Bicocca, Milano, Italy. Phys. Dep. Università degli Studi dell’Insubria, Como, Italy. INFN, Sezione di Bologna, Bologna, Italy. INFN, Laboratori Nazionali di Frascati, Frascati (Rome), Italy. CENBG, Université de Bordeaux, CNRS/IN2P3, Gradignan, France. INFN, Sezione di Roma 1, Rome, Italy. Institute of Nuclear Research of the Russian Academy of Science, Moscow, Russia. Copyright owned by the author(s) under the terms of the Creative Commons Center of Excellence for Advanced Materials and Sensing Devices, Ruder Boskovic INFN Sezione di Bari, Bari, Italy. INFN Sezione di Padova, Padova, Italy. INFN Sezione di Trieste, Trieste, Italy. Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). Institute, Zagreb, Kroatia. © t s L. Ludovici N. Mauri n o p q r m k l j C. Jollet M. Pari M. Prest M. Stipčevic a b c d e f g h i F. Dal Corso M.G. Catanesi C. Brizzolari F. Terranova The ENUBET experiment PoS(ICHEP2020)182 F. Terranova . Over the from 4 ` a a 0 c + 4 → +

production mostly by the detection 4 a 2 francesco.terranova@.ch Speaker ∗ and decays. In thisproject. paper, we present these new developments and the overall status of the The CERN NP06/ENUBET experimenta is designing beam the with first unprecedentedsource. “monitored control neutrino The of original beam”, aim the i.e. of flux,of ENUBET large-angle energy was to and from monitor three-body flavor the semileptonic ofyears, decays the of the ENUBET : technique has at been extended to cover also the monitoring of the Univ. of Milano-Bicocca and INFN, Sez. di Milano-Bicocca,E-mail: Piazza della Scienza 3, Milano, Italy. INFN Laboratori Nazionali di Legnaro, Legnaro (PD), Italy. E 40th International Conference on High EnergyJuly physics 28 - - ICHEP2020 August 6, 2020 Prague, Czech Republic (virtual meeting) ENUBET u PoS(ICHEP2020)182 F. Terranova ). This displacement ◦ 8 . 3% the systematic budget 14 cross-sections and remove < ` a and 4 a 3 system that dilutes the protons up to 4 s. In such a way, the system pulsed at 2-10 ms during the flat top of the accelerator. ms and will be tested at the end of the CERN Long-Shutdown 2 (LS2) [6]. energy reconstruction. It is essential to lower to ` 10 a < horn-based purely static focusing The core of the monitored beams are a rich instrumentation of the decay tunnel that provides At the time of writing, the new beamline has been fully simulated with G4Beamline and ENUBET is aimed at designing a narrow-band neutrino beam at the GeV scale, measuring the The beamline of ENUBET produces a narrow-band beam of neutrinos with a typical energy 10%. It is the first “monitored neutrino beam” [1] and the core technology for a new generation of the rate of the produced at large angles. The ENUBET tunnel instrumentation is based on This proton extraction scheme can be usedstructure in that the static is focusing employed beamline, by as the well, detector to for provide a cosmic time ray suppression. 3. Tunnel instrumentation FLUKA, and the optimizationbased of on a the target and collimators is in progress. This beamline is The proton extraction scheme, proposedat for the the CERN-SPSC at first the timelattice 20 in achieved ms [5], level has and the been latest demonstrated tuning in based 2018 on the simulations of the SPSC all biases due the ensures that the GeV neutrinos producedof in neutral the , first early decay-in-flight non-instrumented of part chargedthe of particles) latest version the do of not beamline the reach ENUBET (decay the beamline,shown this neutrino is in detector. achieved by1. Fig. In two dipoles and An aproton additional set dump, of i.e. advantage quadrupoles of the element this stoppingand configuration the the is primary neutrino the that detector. large have distance notthe Again, interacted between detector this with the the in reduces target, the the amountneutrinos energy of range from non-monitored of the neutrinos DUNE decay-at-rest that or canmeasurements reach [4]. Hyper-Kamiokande. be identified Possible by low-energy the residual detector and used for ancillary physics instantaneous rate in the instrumented decaypile-up tunnel does contribution not to exceed a the few background hundredsthe of is previous kHz version marginal. and and the a The fullto corresponding evaluation account is fluxes for in are a progress. comparable The to same beamline is being re-optimized flux and flavor at 1% level,∼ and the energy of theshort-baseline neutrinos experiments produced to at achieve source a with 1% a precision precision on of the spread of 10% and a large angle between the neutrinos and the target axis ( ENUBET 1. ENUBET and the monitored neutrino beams of DUNE and HyperKamiokandedoubling and the DUNE enhance mass). remarkably Finally, this theiration facility is of discovery the cross-section most experiments reach natural – (equivalent follow-up including ofthe the to the possibility previous to gener- SBN upgrade physics the programme CERN formeasurements ProtoDUNE a and or physics new beyond experimental the campaign Standard focused Model on (see cross-section e.g. [2,3]). 2. Beamline PoS(ICHEP2020)182 [8] ]) GeV [ separation. -layer”. We F. Terranova 0  0 C ( c / p + / 4 17% ' 4 separation and of an inner light-weight photon veto for ns can be achieved for each LCM even in the presence of pile-up or after- + 1 c / ∼ + 4 Bending section of the ENUBET beamline. The section is located between the target area and the Since 2017, we have developed a dedicated event builder to identify and reconstruct positrons and low cross-talk devices developed by FBK [9] are being considered for the final detector. in the calorimeter with highstruction efficiency of and purity. has Morestarts been recently, the with finalized, event the too. builder identification for ofdeposit the In a in recon- the the seed. calorimeter cells event Thecompatible (Lateral builder, seed readout with the for Compact a the event Modules, mip muon reconstruction LCMs) reconstructionand i.e. of t0-layer the is deposits innermost a with compatible layer visible an in energy energythe space candidate between with muon 5 a event. muon and The track 15expected search trajectory are MeV. of of Around clustered the the together the muon, energy a and seed, deposits straight constitute layers is line all in from performed the LCMs the taking forward inner direction. into radial layer account The ofBy the clustering LCMs 2020, exploits toward the the the energy outer time deposit of is the simulatedrecorded energy in by deposit the the in digitizers most the that realistic LCMs. manner read plugging theidentification the SiPM and entire signal waveform without pile-up amplification. subtraction The aretiming algorithms precision under for peak of development but preliminary results show that a carried out the detectorArea R&D [7]. between 2016 The and finalsample choice 2018, the is mostly showers an every at iron-scintillator 4.3 the(Y11 radiation sampling by CERN Kuraray) lengths. calorimeter running East divided along The the Experimental into lateral scintillatorphotosensors modules edge that light of that will the is be tiles collected employed and are bundled by SiPMsphoton on WLS produced top veto fibers by of is Fondazione the Bruno based detector. Kessler on The (FBK).upper plastic The part, scintillators, where the whose SiPMs light are located. isis A transported given detailed in by description of [8]. WLS the fibers performance Theradius of toward final of the the prototype 1 ENUBET m Demonstrator that is will a be 3 built m in long 2021 instrumented and tested decay4. at tunnel CERN with after a LS2. Particle reconstruction in the decay tunnel pulses. Correlated noise may impact on the energy resolution of positrons ( This detector also provides the absolute timing of the events and is thus called the “ Figure 1: decay tunnel. a calorimeter for ENUBET PoS(ICHEP2020)182 decay ` a + ` F. Terranova → + c , enhancing remarkably the physics 4 a 5 candidate). The preliminary performance obtained and the muon range (i.e. the muon energy) can be + ` 2 fluxes. The technique we chose is inspired by T2K and or ` + a 4 and 4 a 6.2 Fig. reports the distribution of the impact point along the tunnel for ∼ with a precision similar to the flux of shows a selection efficiency of about 33 % dominated by the geometrical ` + a

Distribution of selected muons (signal and background) as a function of the position in the 40 m monitoring from pion decays - Since late 2019, we have started the full systematic assessment to demonstrate that ENUBET The original ENUBET technique is not suited to monitor muons from the We identified a set of variables that give information on the reconstructed event topology both . for muons from uses as priors allproduction the data. information from Unlike the T2K,energy, we simulation and include like angular in in distribution the a of priors standard positrons also beam, and the including muons monitoring in hadro- information: the the decay rate, tunnel, and the information efficiency, and a S/N of can achieve the 1% goal on the the reconstructed muons after thefor cut positrons on are the 24% NN and classifier. 2.1, respectively. The corresponding efficiency and S/N 5. since the muons are producedcrossing in the the forward instrumented direction walls and impingeof of into these the the muons tunnel. goes dump from without measured Thanks instrumenting 1 to the to dump the with 10 slow fast MHz/cm andscintillator extraction, radiation cells hard however, detectors the [10], (silicon rate pads, etc.) polysiloxane production rate with at systematics much different betterin depths. than high the energy wide-band standard beams 15% The by precision ionization instrumented chambers thatsingle-particle and can level. identify dump be energy, NP06/ENUBET position can obtained is and rate therefore then at potentiallyflux the equipped monitor of with the a the tool leading to determinereach the of the facility. 6. Systematic evaluation and physics performance for positrons and muons.TMVA These package variables and are used the by eventranges a from is Neural 0 selected Network (background) to (NN) cutting 1 based on (pure on the the output Root classifier of the network, which Figure 2: instrumented decay tunnel. The signal is highlighted by the beige circle. ENUBET PoS(ICHEP2020)182 , JINST 14 F. Terranova et al. GeV and 22% for , IEEE Trans. Nucl. 3 CC in a 500 t detector ` a (i.e. the neutrino energy i ∼ et al. 6 a '  (2018) 141802. 10 h (2015) 155. 120 75 ) at fixed CC and a 4 cm with as the distance of the interaction vertex a  / 4 ' a 50 (2018) P01028. F. Acerbi  10 ' Δ 13 ' (2016) 345; A. Berra (2020) 163379. 6 830 956 , JINST et al. [MiniBooNE], Phys. Rev. Lett. (2020) P08001. (2019) 308. GeV. 15 et al. 19 7 . 0 from pion decay) is 8% for i ' JINST Nucl. Instrum. Meth. A a , CERN-SPSC-2018-034, SPSC-I-248, Geneva, 2018. , Nucl. Instrum. Meth. A ` , CERN-SPSC-2016-036, SPSC-EOI-014, Geneva, 2016. Sensors  a h et al. et al. et al. et al. et al. et al. (2017) 1056; G. Ballerini 64 cm with doi:10.18429/JACoW-IPAC2019-WEPMP035. Sci. arXiv:2010.10268 [hep-ph]. (2019) P02029. 250 ENUBET is thus able to provide a sample of about We are grateful to the organizers of ICHEP2020 for the excellent discussion framework despite ' [7] A. Berra [6] M. Pari, M. Fraser, B. Goddard, V. Kain, L. Stoel and F. Velotti, Proceedings of IPAC 2019, [5] A. Berra [1] A. Longhin, L. Ludovici and F. Terranova, Eur.[2] Phys. J.F. C Acerbi [4] A. A. Aguilar-Arevalo [9] A. Gola [3] L. Delgadillo and P. Huber, “ searches at tagged kaon beams,” [8] F. Acerbi, ' from the beam axis, the relative beam energy width ( ENUBET from the instrumented hadron dump.systematic variations These on additional the priors beam constrain parameters,transport the secondary and flux interactions production once of yields, we the the consider secondariesWe uncertainty plan in in to the the release transfer the line complete and systematic the matrix instrumentation by efficiency. the end oflocated 2021. 50 m after the hadronUsing dump the (baseline: “off-axis 90 narrow-band technique” m) described monitoredneutrino in with [2], energy an we just expected can precision by provide of locating a 1%. relying measurement the on of position final the of state particle the reconstruction. interaction If vertex we in define the detector, i.e.resolution for without the the limitations due to the COVID19 outbreak.Research This Council project has (ERC) received funding under fromprogramme the (Grant European the Agreement European no. 681647) Union’s– and Horizon by MIUR the 2020 (Bando Italian Ministry Research “FARE”, ofOcchialini”, progetto and Education Univ. NuTech). and of Innovation Research Milano-Bicocca (project It 2018-CONT-0128). is also supported byReferences the Dep. of Physics “G. 7. Acknowledgments [10] F. Acerbi