Ponente
Dr.
Silvestro Di Luise
(ETH Zurich)
Descripción
We present an optimization of the neutrino beam which could be produced at CERN and aimed to the newly
proposed deep-underground neutrino observatory LAGUNA-LBNO.
The main goals of LAGUNA-LBNO, a next-generation long-baseline neutrino and antineutrino oscillation
experiment, are to discover CP-violation in the leptonic sector (CPV)
and determine the neutrino mass hierarchy.
In particular LAGUNA-LBNO aims to attain a unique sensitivity
to CPV through the exploration of the first and second oscillation maxima.
This implies that the neutrino beam line must be able to provide neutrinos whose energy distribution
is fairly uniform
from the sub-GeV region up to several GeV's.
The need of a wide-band neutrino beam represents an extremely challenging
requirement as focusing through a magnetic horn is, by principle, effective
for narrow-band neutrino beam where the ideal energy distribution
is peaked around one oscillation maximum.
A novel algorithm
has been then developed to
to search for the optimal configuration of the beam line
with respect to a generic
figure of merit, for example the discovery potential
for the CPV and/or the mass hierarchy.
The procedure relies on an analytical parametrization of the horns shapes
and the figure of merit is maximized through a stochastic
search within the multidimensional space of the
desgin parameters of the beam line elements:
primary beam, target, focusing system (e.g.: horn-reflector layout), decay pipe.
For a given beam line layout the expected neutrino flux energy distribution
is obtained
by means of a full GEANT4 simulation of the primary proton beam interaction in the target,
the secondary hadrons focusing system and the decay pipe.
Specific scenarios for the proton driver and the far detectors have been investigated.
For different CERN SPS proton beam energy and baseline
sensitivity limits will be presented as a function of the beam exposure and the
far detector fiducial mass.
It is worth noting that the proposed method, applied to the LAGUNA-LBNO physics searches,
it is conceived to be
used for the optimal beamline design determination of any future long baseline neutrino oscillation experiment.
Autor primario
Dr.
Silvestro Di Luise
(ETH Zurich)
