Synthesis.

In this thesis different aspects of acoustics present in an underwater neutrino 
telescopes are treated, mainly in two topics: the acoustic positioning system 
used to monitor the positions of the optical modules placed along the detector, 
and the systems for acoustic neutrino detection technique, which is currently 
under study. All studies are framed in two European partnerships for the design, 
construction and operation of undersea neutrino telescope, ANTARES (under 
operation) and KM3NeT (design phase).

Objectives.

The objectives of this study can be summarized in the following aspects:
-	Research and analysis of acoustic positioning system of ANTARES. 
Development of software for the automation of data processing system 
and incorporating the results into the database of the experiment. 
Analysis of data from the system in order to validate its correct operation.
-	Design and development of the acoustic positioning system for the 
KM3NeT telescope, which will be about 20 times larger than ANTARES.
-	Studies to evaluate acoustic parametric generation for the development 
of a compact calibrator capable of generating signals useful to calibrate 
neutrino acoustic detection systems.

Elements of the methodology to emphasize.

It should be noted here that the work has been developed within the framework 
of two international collaborations: ANTARES and KM3NeT, with the support of 
European and National funds. Due to the context and nature of activities it has 
been needed training in different fields: astroparticle and neutrino telescopes, 
but also in other areas such as underwater acoustics. It has also been needed 
to develop abilities and skills in various areas: instrumentation, applications, 
data analysis, etc. More specifically, we have worked on software for the 
development and analysis at ANTARES and in underwater acoustic 
technologies for the development of KM3NeT acoustic positioning system with 
the requirements imposed by the infrastructure: hostile environment (in the sea 
about 3000m depth under high pressure), high precision required (10 cm over 
distances of the order of kilometers), low power consumption, communication 
capabilities and configuration, etc. For the development of the compact 
calibrator to reproduce neutrino like signals, pioneering studies of parametric 
generation in cases with cylindrical symmetry and transient signals have been 
achieved and applied in order to develop a device that can produce a highly 
directive transient bipolar signal.

Results achieved.

The results achieved in the realization of this thesis can be summarized in 
response to the three issues under discussion, acoustic positioning KM3NeT, 
ANTARES project collaboration and design and evaluation of techniques for 
acoustic detection of neutrinos:
-	Within the collaboration in the ANTARES neutrino telescope, numerous 
studies have been conducted to verify the stability and accuracy of the 
various components of the positioning system and of the results. Also an 
interface (using C++/Oracle in Linux environment) has been done that 
allows the incorporation of data from the acoustic positioning system in 
the database and thus provide these for the subsequent reconstruction of 
particles detected.
-	Design and development of acoustic positioning system for KM3NeT 
neutrino telescope. As part of this project a system of acoustic 
transceivers for a new positioning system has been developed and will 
be tested and validated during the summer of 2011 in the NEMO-
KM3NeT prototype at 3500 m deep sea near Capo Passero (Sicily).
-	In relation to the development of an acoustic calibrator that mimics the 
pulse of the neutrino interaction, studies for the evaluation of parametric 
sound generation technique for this purpose has been done, obtaining 
successful and promising results for the possible construction of a 
compact calibrator device, whose prototype is being developed.

These activities and scientific and technological results have been useful for the 
development in the field of underwater neutrino telescopes, and as such, they 
have been published in international scientific journals.