We investigate the search for heavy Majorana neutrinos stemming from a composite model scenario at the upcoming LHC Run II at a centre of mass energy of 13 TeV. While previous studies of the ...composite Majorana neutrino were focussed on gauge interactions via magnetic type transition coupling between ordinary and heavy fermions (with mass
m
∗
) here we complement the composite model with contact interactions at the energy scale
Λ
and we find that the production cross sections are dominated by such contact interactions by roughly two/three orders of magnitude. This mechanism provides therefore very interesting rates at the prospected luminosities. We study the same-sign di-lepton and di-jet signature (
p
p
→
ℓ
ℓ
j
j
) and perform a fast detector simulation based on
Delphes
. We compute 3
σ
and 5
σ
contour plots of the statistical significance in the parameter space (
Λ
,
m
∗
). We find that the potentially excluded regions at
s
=
13
TeV are quite larger than those excluded so far at Run I considering searches with other signatures.
We consider the production at the LHC of exotic composite leptons of charge Q = +2e. Such states are allowed in composite models that contain extended isospin multiplets (IW = 1 and IW = 3/2). These ...doubly charged leptons couple with standard model (SM) fermions via gauge interactions, thereby delineating and restricting their possible decay channels. We discuss the production cross section at the LHC of L super(++) (pp arrow right L super(++), l super(-)) and concentrate on the leptonic signature deriving from the cascade decays L super(++) arrow right W super(+) l super(+) arrow right l super(+) l super(+) nul i.e. pp arrow right l super(-)(l super(+)l super(+))nul showing that the invariant mass distribution of the like-sign dilepton has a sharp end point corresponding to excited lepton mass m*. We find that the radicals = 7 TeV run is sensitive at the 3-sigma (5-sigma) level to a mass of the order of 600 GeV if L = 10 fb super(-1) (L = 20 fb super(-1)). The radicals = 14 TeV run can reach a sensitivity at 3-sigma (5-sigma) level up to m* = 1 TeV for L = 20 fb super(-1) (L = 60 fb super(-1)).
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.
Nickel nanoparticles are prepared through thermolysis or polyol procedures and they are fully characterized through TEM and XRD. The catalytic efficiencies are tested toward the hydrogenation ...reaction of 4-nitrophenol, which was spectrophotometrically detected. A significant improvement of the reaction rate and turnover number (TON) and frequency (TOF) is observed using alkyl amine-stabilized nanoparticles, likely due to their reduced surface steric hindrance. However, the polymer stabilized-nanocatalysts show a better selectivity for product formation, since only hydrogenation products are observed, while azo-benzene derivatives are detected when alkyl amine-stabilized nanoparticles are used. The findings indicate an important impact of surface properties of colloids on the catalysed reaction.
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•Ni nanoparticles are prepared through thermolysis and polyol procedures.•Ni colloids have similar dimensions and structure but different capping agents.•The reduction of 4-NPh catalysed by Ni NPs is spectrophotometrically monitored.•Alkyl amine-stabilized NPs show the higher reaction rate and TON value.•Azocompounds are also formed when the catalyst is stabilized by alkyl amines.
Hydrogenated amorphous silicon is a well-known detector material for its radiation resistance. For this reason it has been used in particle beam flux measurements and in solar panels designed for ...space applications. This study concern 10μm thickness, p-i-n and charge selective contacts planar diode detectors which were irradiated with neutrons to two fluence values: 1016neq/cm2 and 5 × 1016neq/cm2. In order to evaluate their radiation resistance, detector leakage current and response to x-ray photons have been measured. The effect of annealing for performance recovery at 100 °C for 12 and 24 h has also been studied. The results for the 1016neq/cm2 irradiation show a factor 2 increase in leakage current that is completely recovered after annealing for p-i-n devices while charge selective contacts devices show an overall decrease of the leakage current at the end of the annealing process compared to the measurement before the irradiation. X-ray dosimetric sensitivity degrades, for this fluence, at the end of irradiation, but partially recovers for charge selective contact devices and increases for p-i-n devices at the end of the annealing process. Concerning the 5 × 1016neq/cm2 irradiation test (for p-i-n structures only), due to the activation that occurred during the irradiation phase, the measurements were taken after 146 days of storage at around 0 °C, during this period, a self-annealing effect may have occurred. Therefore, the results after irradiation and storage show a noticeable degradation in leakage current and x-ray sensitivity with a small recovery after annealing.
In recent years, urban trekking and geotourism have gained relevance in the tourism industry. This has been accompanied by an increasing use of digital tools and techniques for developing immersive ...touristic experiences. The HUSH project aim is to enhance and disseminate the scientific and naturalistic heritage of urban areas by means of a mobile application. The naturalistic and geological components with relevant scientific value are first identified and tagged as Points of Interest (POIs). Then, high quality multimedia contents are created for each of them. Using the HUSH app and implementing Augmented Reality techniques, users can explore these contents by framing the POIs with their device. They can decide which POIs they want to visit by using keyword-search, by selecting a predefined path or by means of 'intelligent search', which applies data mining techniques to users' data. Moreover, they can propose the addition of new POIs by using the Scientific Reporter tool and rate POIs they visit.
Data storage and data access represent the key of CPU-intensive and data-intensive high performance Grid computing. Hadoop is an open-source data processing framework that includes fault-tolerant and ...scalable distributed data processing model and execution environment, named MapReduce, and distributed File System, named Hadoop distributed File System (HDFS). HDFS was deployed and tested within the Open Science Grid (OSG) middleware stack. Efforts have been taken to integrate HDFS with gLite middleware. We have tested the File System thoroughly in order to understand its scalability and fault-tolerance while dealing with small/medium site environment constraints. To benefit entirely from this File System, we made it working in conjunction with Hadoop Job scheduler to optimize the executions of the local physics analysis workflows. The performance of the analysis jobs which used such architecture seems to be promising, making it useful to follow up in the future.
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