Development of mirrors made of chemically tempered glass foils for future X-ray telescopes

Thin slumped glass foils are considered good candidates for the realization of future X-ray telescopes with large effective area and high spatial resolution. However, the hot slumping process affects the glass strength, and this can be an issue during the launch of the satellite because of the high kinematical and static loads occurring during that phase. In the present work we have investigated the possible use of Gorilla glass (produced by Corning), a chemical tempered glass that, thanks to its strength characteristics, would be ideal. The un-tempered glass foils were curved by means of an innovative hot slumping technique and subsequently chemically tempered. In this paper we show that the chemical tempering process applied to Gorilla glass foils does not affect the surface micro-roughness of the mirrors. On the other end, the stress introduced by the tempering process causes a reduction in the amplitude of the longitudinal profile errors with a lateral size close to the mirror length. The effect of the overall shape changes in the final resolution performance of the glass mirrors was studied by simulating the glass foils integration with our innovative approach based on glass reinforcing ribs. The preliminary tests performed so far suggest that this approach has the potential to be applied to the X-ray telescopes of the next generation.Comment: Accepted for publication in Experimental Astronomy. Author's accepted manuscript posted to arXiv.org as permitted by Springer's Self-Archiving Polic

The ENUBET Beamline

The ENUBET ERC project (2016-2021) is studying a narrow band neutrino beam where lepton production can be monitored at single particle level in an instrumented decay tunnel. This would allow to measure $\nu_{\mu}$ and $\nu_{e}$ cross sections with a precision improved by about one order of magnitude compared to present results. In this proceeding we describe a first realistic design of the hadron beamline based on a dipole coupled to a pair of quadrupole triplets along with the optimisation guidelines and the results of a simulation based on G4beamline. A static focusing design, though less efficient than a horn-based solution, results several times more efficient than originally expected. It works with slow proton extractions reducing drastically pile-up effects in the decay tunnel and it paves the way towards a time-tagged neutrino beam. On the other hand a horn-based transferline would ensure higher yields at the tunnel entrance. The first studies conducted at CERN to implement the synchronization between a few ms proton extraction and a horn pulse of 2-10 ms are also described.Comment: Poster presented at NuPhys2018 (London 19-21 December 2018). 4 pages, 3 figure

Muon detection in electron-positron annihilation for muon collider studies

The investigation of the energy frontier in physics requires novel concept for future colliders. The idea of a muon collider is very appealing since it would aim to study particle collisions up to tens of TeV energy while offering a cleaner experimental environment with respect to hadronic colliders. One key element in the muon collider design is muon production with small emittance. Recently, the Low EMittance Muon Accelerator (LEMMA) collaboration has explored the close-to-threshold muon production by 45 GeV positron annihilating in a low Z material target. Muons are emerging with a natural small emittance. In this paper we describe the performance of a system of segmented absorbers with alternating active layers realized with fast Cherenkov detectors and a muon identification technique based on it. Passive layers were made of tungsten. Muons and electron beams data were collected in September 2018 at the H2 line in the North Area of the Conseil Européen pour la Recherche Nucléaire (CERN)

Monitored neutrino beams and the next generation of high precision cross section experiments

The main source of systematic uncertainty on neutrino cross section measurements at the GeV scale originates from the poor knowledge of the initial flux. The reduction of this uncertainty to 1% can be achieved through the monitoring of charged leptons produced in association with neutrinos. The goal of the ENUBET ERC project is to prove the feasibility of such a monitored neutrino beam. In this contribution, the final results of the ERC project, together with the complete assessment of the feasibility of its concept, are presented. An overview of the detector technology for a next generation of high precision neutrino-nucleus cross section measurements, to be performed with the ENUBET neutrino beam, is also given

Design and performance of the ENUBET monitored neutrino beam

The ENUBET project is aimed at designing and experimentally demonstrating the concept of monitored neutrino beams. These novel beams are enhanced by an instrumented decay tunnel, whose detectors reconstruct large-angle charged leptons produced in the tunnel and give a direct estimate of the neutrino flux at the source. These facilities are thus the ideal tool for high-precision neutrino cross-section measurements at the GeV scale because they offer superior control of beam systematics with respect to existing facilities. In this paper, we present the first end-to-end design of a monitored neutrino beam capable of monitoring lepton production at the single particle level. This goal is achieved by a new focusing system without magnetic horns, a 20 m normal-conducting transfer line for charge and momentum selection, and a 40 m tunnel instrumented with cost-effective particle detectors. Employing such a design, we show that percent precision in cross-section measurements can be achieved at the CERN SPS complex with existing neutrino detectors

Monitored neutrino beams: NP06/ENUBET

The main source of systematic uncertainty on neutrino cross section measurements at the GeV scale is represented by the poor knowledge of the initial flux. The goal of cutting down this uncertainty to 1% can be achieved through the monitoring of charged leptons produced in association with neutrinos, by properly instrumenting the decay region of a conventional narrow-band neutrino beam. The ENUBET project has been funded by the ERC in 2016 to prove the feasibility of such a monitored neutrino beam and is cast in the framework of the CERN Neutrino Platform (NP06) and the Physics Beyond Colliders initiative. This contribution reports the final design of the horn-less beamline able to deliver a meson yield large enough to perform a ve cross section measurement at 1% precision in about 3 years of data taking at CERN-SPS with a ProtoDUNE-like detector. The final configuration of the tunnel instrumentation and its implementation on a large-scale prototype, the Demonstrator, are also described. Finally the particle identification performance is presented together with the first assessment of the lepton monitoring impact in the reduction of the hadroproduction systematics on the neutrino flux

Status of the ENUBET Project

The ENUBET Collaboration is designing the first “monitored neutrino beam”: a beam with an unprecedented control of the flux, energy and flavor of neutrinos at source. In particular, ENUBET monitors the νe production mostly by the detection of large angle positrons from three body semileptonic decays of kaons: K+ → e+π0νe. In this paper, we present the status of the Project and the 2018-2019 advances on proton extraction, transfer line, particle identification in the decay tunnel and beam performance

First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform

The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber with an active volume of 7.2× 6.1× 7.0 m3. It is installed at the CERN Neutrino Platform in a specially-constructed beam that delivers charged pions, kaons, protons, muons and electrons with momenta in the range 0.3 GeV/c to 7 GeV/c. Beam line instrumentation provides accurate momentum measurements and particle identification. The ProtoDUNE-SP detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment, and it incorporates full-size components as designed for that module. This paper describes the beam line, the time projection chamber, the photon detectors, the cosmic-ray tagger, the signal processing and particle reconstruction. It presents the first results on ProtoDUNE-SP\u27s performance, including noise and gain measurements, dE/dx calibration for muons, protons, pions and electrons, drift electron lifetime measurements, and photon detector noise, signal sensitivity and time resolution measurements. The measured values meet or exceed the specifications for the DUNE far detector, in several cases by large margins. ProtoDUNE-SP\u27s successful operation starting in 2018 and its production of large samples of high-quality data demonstrate the effectiveness of the single-phase far detector design