Search results for "Detectors"
showing 10 items of 2229 documents
The MuPix high voltage monolithic active pixel sensor for the Mu3e experiment
2015
Mu3e is a novel experiment searching for charged lepton flavor violation in the rare decay μ → eee. In order to reduce background by up to 16 orders of magnitude, decay vertex position, decay time and particle momenta have to be measured precisely. A pixel tracker based on 50 μm thin high voltage monolithic active pixel sensors (HV-MAPS) in a magnetic field will deliver precise vertex and momentum information. Test beam results like an excellent efficiency of >99.5% and a time resolution of better than 16.6 ns obtained with the MuPix HV-MAPS chip developed for the Mu3e pixel tracker are presented.
Neutrino Unification
2000
Present neutrino data are consistent with neutrino masses arising from a common seed at some ``neutrino unification'' scale $M_X$. Such a simple theoretical ansatz naturally leads to quasi-degenerate neutrinos that could lie in the electron-volt range with neutrino mass splittings induced by renormalization effects associated with supersymmetric thresholds. In such a scheme the leptonic analogue of the Cabibbo angle $\theta_{\odot}$ describing solar neutrino oscillations is nearly maximal. Its exact value is correlated with the smallness of $\theta_{reactor}$. These features agree both with latest data on the solar neutrino spectra and with the reactor neutrino data. The two leading mass-ei…
Parameter Degeneracy in Flavor-Dependent Reconstruction of Supernova Neutrino Fluxes
2008
We reexamine the possibility of reconstructing the initial fluxes of supernova neutrinos emitted in a future core-collapse galactic supernova explosion and detected in a Megaton-sized water Cherenkov detector. A novel key element in our method is the inclusion, in addition to the total and the average energies of each neutrino species, of a "pinching" parameter characterizing the width of the distribution as a fit parameter. We uncover in this case a continuous degeneracy in the reconstructed parameters of supernova neutrino fluxes at the neutrinosphere. We analyze in detail the features of this degeneracy and show how it occurs irrespective of the parametrization used for the distribution …
Resurrection of large lepton number asymmetries from neutrino flavor oscillations
2016
We numerically solve the evolution equations of neutrino three-flavor density matrices, and show that, even if neutrino oscillations mix neutrino flavors, large lepton number asymmetries are still allowed in certain limits by Big Bang Nucleosynthesis (BBN).
Neutrino mass in supersymmetry
2009
10 páginas, 8 figuras.-- El PDF es la versión pre-print (arXiv:0911.3103v1).-- Trabajo presentado al SUSY09: 7th International Conference on Supersymmetry and the Unification of Fundamental Interactions.
Third generation SUSY searches in ATLAS
2016
Supersymmetry (SUSY) is one of the most popular and promising extensions to the Standard Model (SM) of particle physics. It predicts partner particles for all SM particles with a spin difference of $1/2$. These SUSY partners, if they exist within a reachable energy scale, should be produced at the Large Hadron Collider (LHC). The events are usually characterized by high missing transverse energy and can have varying jet and lepton multiplicities, depending on the model used. Searches for partners of third generation squarks are of special interest because of their special event topologies.\\ Many searches have been performed in proton-proton collisions at $\sqrt{s}=13$ TeV at the LHC with t…
A Brief Discussion on the Performance of the MoEDAL and the LHCf Experiments
2018
The Monopole and Exotics Detector at the LHC (MoEDAL) experiment is an experiment dedicated to searching for beyond standard model (BSM) particles like magnetic monopoles, highly ionizing particles and slow-moving supersymmetric particles. In many ways, this detector complements the BSM searches of ATLAS and CMS. In this document, a brief description of the MoEDAL detector and performance is given. The Large Hadron Collider Forward (LHCf) experiment, on the other hand, is dedicated to measuring the neutral particles produced in the hadronic collision in the very forward region. This document also briefly discusses the LHCf detector and its performance.
Neutron emission from electromagnetic dissociation of Pb nuclei at $\sqrt {s_{NN}} = 2.76$ TeV measured with the ALICE ZDC
2014
The ALICE Zero Degree Calorimeter system (ZDC) is composed of two identical sets of calorimeters, placed at opposite sides with respect to the interaction point, 114 meters away from it, complemented by two small forward electromagnetic calorimeters (ZEM). Each set of detectors consists of a neutron (ZN) and a proton (ZP) ZDC. They are placed at zero degrees with respect to the LHC axis and allow to detect particles emitted close to beam direction, in particular neutrons and protons emerging from hadronic heavy-ion collisions (spectator nucleons) and those emitted from electromagnetic processes. For neutrons emitted by these two processes, the ZN calorimeters have nearly 100% acceptance. Du…
Topological and Central Trigger Processor for 2014 LHC luminosities
2012
The ATLAS experiment is located at the European Center for Nuclear Research (CERN) in Switzerland. It is designed to observe phenomena that involve highly massive particles produced in the collisions at the Large Hadron Collider (LHC): the world’s largest and highest-energy particle accelerator. Event triggering and Data Acquisition is one of the extraordinary challenges faced by the detectors at the high luminosity LHC collider. During 2011, the LHC reached instantaneous luminosities of 4 10^33 cm−1 s−1 and produced events with up to 24 interactions per colliding proton bunch. This places stringent operational and physical requirements on the ATLAS Trigger in order to reduce the 40MHz coll…
Search for heavy neutrinos at the NA48/2 and NA62 experiments at CERN
2018
© The Authors, published by EDP Sciences. The NA48/2 experiment at CERN has collected large samples of charged kaons decaying into a pion and two muons for the search of heavy nuetrinos. In addition, its successor NA62 has set new limits on the rate of charged kaon decay into a heavy neutral lepton (HNL) and a lepton, with = e, µ, using the data collected in 2007 and 2015. New limits on heavy neutrinos from kaon decays into pions, muons and positrons are presented in this report.