1,204 research outputs found
OPERA: waiting for the tau
The OPERA experiment, whose aim is the direct observation of nu_mu ~> nu_tau
oscillations in appearance mode in the CNGS high-energy neutrino beam, consists
of a high-granularity modular target of nuclear emulsions-lead "bricks", richly
instrumented with electronic detectors necessary for the location of neutrino
interactions and kinematic analysis. After the first short runs of August 2006,
October 2006 and October 2007, the experiment started early this summer its
first long physics run (about 150 days). Operating at the final target mass of
1.35 kton, the 2008 run can realistically offer the first chance to observe a
tau originated from a flavour oscillated nu_mu. This contribution will discuss
the different aspects of the experiment, the challenges of the data handling
and the recent achievements. It will also outline the various steps required
for the analysis in nuclear emulsions from the "brick finding" to the vertex
reconstruction.Comment: 6 pages, 3 figures. Proceedings of the "XXVIII Physics in
Collisions", Perugia, Italy, 25-28 June 200
Large-angle scattering of multi-GeV muons on thin Lead targets
The probability of large-angle scattering for multi-GeV muons in thin () lead targets is studied. The new estimates presented here are
based both on simulation programs (GEANT4 libraries) and theoretical
calculations. In order to validate the results provided by simulation, a
comparison is drawn with experimental data from the literature. This study is
particularly relevant when applied to muons originating from
interactions of CNGS beam neutrinos. In that circumstance the process under
study represents the main background for the search in
the channel for the OPERA experiment at LNGS. Finally, we also
investigate, in the CNGS context, possible contributions from the muon
photo-nuclear process which might in principle also produce a large-angle muon
scattering signature in the detector
Overview on neutrino oscillations
I will discuss recent achievements in the study of neutrino oscillations obtained with the T2K, OPERA and ICARUS long-baseline neutrino experiments
An Appraisal of Muon Neutrino Disappearance at Short Baseline
Neutrino physics is nowadays receiving more and more attention as a possible
source of information for the long standing problem of new Physics beyond the
Standard Model. The recent measurements of the third mixing angle
in the standard mixing oscillation scenario encourage to pursue the still
missing results on the leptonic CP violation and the absolute neutrino masses.
However, several puzzling and incomplete measurements are in place which
deserve an exhaustive evaluation and study. We will report about the present
situation of the muon disappearance measurements at small in the context
of the current CERN project to revitalize the neutrino field in Europe and the
search for sterile neutrinos. We will then illustrate the achievements that a
double muon spectrometer can attain in terms of discovery of new neutrino
states, performing a newly developed analysis.Comment: 19 pages, 8 figures, to be published in "Advances in High Energy
Physics
El Silogismo Argentino
La ley de economia es una de las demostraciones mis actuales y complejas del espectro de ley de nuestra 6poca
CP violation and mass hierarchy at medium baselines in the large theta(13) era
The large value of theta(13) recently measured by rector and accelerator
experiments opens unprecedented opportunities for precision oscillation
physics. In this paper, we reconsider the physics reach of medium baseline
superbeams. For theta(13) ~ 9 degree we show that facilities at medium
baselines -- i.e. L ~ O(1000 km) -- remain optimal for the study of CP
violation in the leptonic sector, although their ultimate precision strongly
depends on experimental systematics. This is demonstrated in particular for
facilities of practical interest in Europe: a CERN to Gran Sasso and CERN to
Phyasalmi nu_mu beam based on the present SPS and on new high power 50 GeV
proton driver. Due to the large value of theta(13), spectral information can be
employed at medium baselines to resolve the sign ambiguity and determine the
neutrino mass hierarchy. However, longer baselines, where matter effects
dominate the nu_mu->nu_e transition, can achieve much stronger sensitivity to
sign(Delta m^2) even at moderate exposures.Comment: 14 pages, 14 figures, version to appear in EPJ
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