718 research outputs found
The SHiP experiment and the RPC technology
No full textThe discovery of the Higgs boson has fully confirmed the Standard Model of particles and fields. Nevertheless, there are still fundamental phenomena, like the existence of dark matter and the baryon asymmetry of the Universe, which deserve an explanation that could come from the discovery of new particles. The SHiP experiment at CERN meant to search for very weakly coupled particles in the few GeV mass domain has been recently proposed. The existence of such particles, foreseen in Beyond Standard Models, is largely unexplored. A beam dump facility using high intensity 400 GeV protons is a copious source of such unknown particles in the GeV mass range. The beam dump is also a copious source of neutrinos and in particular it is an ideal source of tau neutrinos, the less known particle in the Standard Model. We report the physics potential of such an experiment and describe the use of the RPC technology therein. An anchillary measurement of the charm cross-section will be carried out in July 2018 and RPC are used as a muon detector. We also describe the design and construction of these new chambers.The discovery of the Higgs boson has fully confirmed the Standard Model of particles and fields. Nevertheless, there are still fundamental phenomena, like the existence of dark matter and the baryon asymmetry of the Universe, which deserve an explanation that could come from the discovery of new particles. The SHiP experiment at CERN meant to search for very weakly coupled particles in the few GeV mass domain has been recently proposed. The existence of such particles, foreseen in Beyond Standard Models, is largely unexplored. A beam dump facility using high intensity 400 GeV protons is a copious source of such unknown particles in the GeV mass range. The beam dump is also a copious source of neutrinos and in particular it is an ideal source of tau neutrinos, the less known particle in the Standard Model. We report the physics potential of such an experiment and describe the use of the RPC technology therein. An anchillary measurement of the charm cross-section will be carried out in July 2018 and RPC are used as a muon detector. We also describe the design and construction of these new chambers
The SND@LHC Experiment
No full textSND@LHC, Scattering and Neutrino Detector at the LHC, is a compact experiment designed to perform measurements with neutrinos produced at the LHC in the unexplored pseudo-rapidity region of 7.2< \eta < 8.4, complementary to all the other experiments at the LHC. The experiment was approved in March 2021. It was constructed in about one year and it is now taking data during the Run 3 of the LHC. In this paper we review the detector concept, the physics case and the status of the data taking
The SHiP physics program
No full textThe discovery of the Higgs boson has fully confirmed the Standard Model of particles and fields. Nevertheless, there are still fundamental phenomena, like the existence of dark matter and the baryon asymmetry of the Universe, which deserve an explanation that could come from the discovery of new particles. The SHiP experiment at CERN meant to search for very weakly coupled particles in the few GeV mass domain has been recently proposed. The existence of such particles, foreseen in different theoretical models beyond the Standard Model, is largely unexplored. A beam dump facility using high intensity 400 GeV protons is a copious source of such unknown particles in the GeV mass range. The beam dump is also a copious source of neutrinos and in particular it is an ideal source of tau neutrinos, the less known particle in the Standard Model. Indeed, tau anti-neutrinos have not been directly observed so far. We report the physics potential of such an experiment including the tau neutrino magnetic moment
The SHiP facility at CERN
No full textSearches for new physics with accelerators are being performed at the LHC, looking for high massive particles coupled to matter with ordinary strength. A new experimental facility meant to search for very weakly coupled particles in the few GeV mass domain has been recently proposed. The existence of such particles, foreseen in dierent theoretical models beyond the Standard Model, is largely unexplored from the experimental point of view. A beam dump facility, built at CERN in the north area, using 400 GeV protons is a copious factory of charmed hadrons and could be used to probe the existence of such particles. The beam dump is also an ideal source of tau neutrinos, the less known particle in the Standard Model. In particular, tau anti-neutrinos have not been directly observed so far. We report the physics potential of such an experiment and outline the performances of a detector operating at the same facility for the search for the tau --> mu mu mu deca
The major achievements of the OPERA experiment and its legacy
No full textThe OPERA experiment was designed to discover the ντ appearance in a pure νμ beam, resulting from neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of an emulsion/lead target complemented by electronic detectors and was exposed, from 2008 to 2012, to the (CERN Neutrinos to Gran Sasso (CNGS)) beam, an almost pure νμ beam with a baseline of 730 km, collecting a total of 1.8. 1020 protons on target. OPERA was unique in its capability of detecting all three neutrino flavors. OPERA discovered νμ → ντ oscillations in appearance mode with a significance of 6.1σ. In this review, we report the major achievements of the OPERA experiment and its legacy in the nuclear emulsion technology
San Camillo de Lellis e i Camilliani fra l’Abruzzo e Roma
No full textSaggi relativi a San Camillo de Lellis e alla storia dell'ordine dei Ministri degli Infermi in Abruzz
Nonclassical minimizing surfaces with smooth boundary
No full textWe construct a Riemannian metric g on R4(arbitrarily close to the euclidean one) and a smooth simple closed curve Γ ⊂ R4such that the unique area minimizing surface spanned by Γ has infinite topology. Furthermore the metric is almost Kähler and the area minimizing surface is calibrated
The SHiP project at CERN
No full textThe discovery of the Higgs boson has fully confirmed the Standard Model of particles and fields. Nevertheless, there are still fundamental phenomena, like the existence of dark matter and the baryon asymmetry, which deserve an explanation that could come from the discovery of new particles. Searches for new physics with accelerators are performed at the LHC, looking for high massive particles coupled to matter with ordinary strength. A new experimental facility at CERN meant to search for very weakly coupled particles in the few GeV mass domain has been recently proposed. The existence of such particles, foreseen in different theoretical models beyond the Standard Model, is largely unexplored. A beam dump facility using 400 GeV protons is a copious factory of charmed hadrons and could be used to probe the existence of such particles. The beam dump is also a copious source of neutrinos and in particular it is an ideal source of tau neutrinos, the less known particle in the Standard Model. Indeed, tau anti-neutrinos have not been directly observed so far. We report the physics potential of such an experiment. Resistive Plate Chambers could play a role in the SHiP detector
Estimates and regularity results for the DiPerna-Lions flow
No full textIn this paper we derive new simple estimates for ordinary differential equations
with Sobolev coefficients. These estimates not only allow to recover some old and recent
results in a simple direct way, but they also have some new interesting corollaries
Regular selections for multiple-valued functions
No full textGiven a multiple-valued function f, we deal with the problem of selecting its single valued branches. This problem can be stated in a rather abstract setting considering a metric space E and a finite group G of isometries of E. Given a function f which takes values in the equivalence classes of E/G, the problem consists in finding a map g with the same domain as f and taking values in E, such that at every point t the equivalence class of g(t) coincides with f(t). If the domain of f is an interval, we show the existence of a function g with these properties which, moreover, has the same modulus of continuity of f. In the particular case where E is the product of Q copies of ℝ n and G is the group of permutations of Q elements, it is possible to introduce a notion of differentiability for multiple valued functions. In this case, we prove that the function g can be constructed in such a way to preserve C k,α regularity. Some related problems are also discussed
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