The NA48/2 experiment at CERN collected in 2003-2004 a large sample of charged kaon decays with multiple charged particles in the final state. A new upper limit on the rate of the lepton number ...violating decay K ± → π ± μ ± μ ± obtained from this sample is reported. Moreover searches for two-body resonances in the K ± → πμμ, decays (including heavy neutral leptons and inflatons) in the accessible range of masses and lifetimes are presented. During the 2016 run the NA62 experiment has collected data with a dedicated trigger for kaon decays with two muons in the final state. Preliminary results on the statistics collected during a period of two weeks for the decay K + → π+μ+μ− will be presented. The NA62 experiment has good potential for the studies of rare K + decays in addition to its main goal, the measurement of the branching ratio of the decay K + → π ν ν ¯ .
The necessity to reduce the weight of transport structures, such as cars and airplanes, has become more important due to gas emission regulations. In this regard, the use of hybrid structures made of ...steel and aluminum is a way to achieve this goal. Joining aluminum to steel is a great challenge and Friction Stir Spot Welding (FSSW) has become as a new potential welding technique to produce dissimilar joints. Despite Friction Stir Welding has been studied on different similar joints, the information related to the influence of FSSW parameters on the evolution of aluminum-steel joints is scarce. So, the effect of the tool geometry and its penetration depth during FSSW of AA5052–LCS (Low Carbon Steel) joints, has been studied. During FSSW, axial load and consumed electrical current were recorded in order to improve the understanding of the welding process. Macro and microstructural characterization was done on the cross section of the welded spots. The mechanical properties of the joints were determined by microhardness profiles and by Peel and Cross Tension tests. The fracture loads increased when the tool penetration depth goes up. The tool geometry optimization also increased the fracture loads.
Particle panels for construction are environmentally favorable, as they allow the combination of different components (as is the case with agro-industrial waste from the production and processing of ...food and products derived from agricultural activities). The objective of this article is to analyze studies focused on the use of cassava by-products in the production of panels for civil construction/furniture in the last 10 years through a bibliographical survey, as well as to present a preliminary analysis of the feasibility of using cassava by-products to manufacture particle panels in their natural state. As a result, the theoretical search detected the gap created by the scarcity of published studies on the topic. On the other hand, the experimental analysis indicated the promising potential of using the cassava by-product for panel production, provided that the weaknesses initially indicated in this research can be addressed.
NA62 RICH performance: measurement and optimization Anzivino, G.; Barbanera, M.; Bizzeti, A. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2020, Volume:
952
Journal Article
Peer reviewed
Open access
The Ring Imaging Cherenkov detector of the NA62 experiment at CERN SPS was commissioned in 2014, but the optimal performance was achieved in 2016 after the precise mirror alignment with reconstructed ...tracks. The measurement and monitoring of basic performance parameters is discussed: ring radius resolution, ring centre resolution, single hit resolution and mean number of hits per ring. The performance is measured with 2016 data on the positron sample. Different contributions to the resolutions are calculated.
The role of the NA62 RICH in the BR(K+→π+νν̄) measurement Volpe, R.; Anzivino, G.; Aisa, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2020, Volume:
952
Journal Article
Peer reviewed
The NA62 experiment aims to measure the BR(K+→π+νν̄) with a 10% precision. One of the main backgrounds comes from the decay K+→μ+ν, therefore a highly powerful pion/muon separation is needed. The ...NA62 RICH, together with the calorimeter system, provides an accurate particle identification which has been essential to obtain the first results of the NA62 K+→π+νν̄ analysis, based on 2016 data. Two different algorithms have been exploited which, used in combination, allowed to get a pion reconstruction and identification efficiency of 75%, with a muon suppression factor of about 500, in the momentum range 15–35 GeV/c.
The vertex detectors for the future hadronic colliders will operate under proton fluencies above 1016 p/cm2. Crystalline Silicon detector technology, up to now, has kept the pace of the increasing ...fluencies in the LHC era and it is still the prevalent vertex detector material for the present and for the immediate future. Looking ahead in time, an alternative solution for such a detector has to be found because for the future there is no guarantee that Crystalline Silicon will hold this challenge. For this reason the development of hydrogenated amorphous silicon vertex detectors based on 3D-technology have been proposed and the technological solutions in order to build these detectors are described in this paper.
Status of the NA62 ring imaging Cherenkov detector Cenci, P.; Anzivino, G.; Aisa, D. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2020, Volume:
952
Journal Article
Peer reviewed
The Ring Imaging Cherenkov detector of the NA62 experiment at the CERN SPS is a key element of particle identification in the NA62 experimental strategy. The detector fulfills different conditions: ...to distinguish pions from muons with a muon rejection factor of O(102) in the NA62 momentum range of operation, between 15 and 35 GeV/c; to measure particle arrival time in the decay region with a precision better than 100 ps; to provide fast signals and reference time to the NA62 trigger system. The main design aspects and functional characteristics, as well as the performance of the detector measured with the data taken in the first NA62 physics runs, will be summarized in this paper.
•The NA62 experiment aims to measure the branching ratio of the K+→π+νν¯ decay.•The NA62 RICH performance fulfills the experiment requirements.•Pion–muon identification is performed with a muon rejection factor of O(102).•Time resolution with precision better than 100 ps is achieved.•The RICH is a key element to select charged particles in the trigger system.
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