OYSTER

The observation of high-energy cosmic neutrinos, produced in distant astrophysical accelerators (and possibly by means of more exotic processes as well), has turned into one of the major challenges of today's astroparticle physics, motivated by the possibility to open a new observational window on the distant Universe. In this context, the ANTARES detector (Astronomy with a Neutrino Telescope and Abyss environmental RESearch) is currently under deployment offshore Toulon (France). Since December 2007, 10 out of the 12 detector lines are operational and the telescope is expected to be achieved by May 2008. It is already the largest neutrino telescope in the Northern Hemisphere and is expected to play a key role in the upcoming years as the first neutrino telescope deployed and taking data in the Mediterranean. A massive technical effort has been made to design, develop and construct the neutrino telescope and many obstacles have been overcome to refine the technology needed to work in the hostile undersea environment, as demonstrated by the smooth operation of the current 10-lines detector. At this point, a comparable scientific effort is needed in order to exploit at best the capabilities of such a novel instrument, and the first years of operation of the detector will be crucial in the setting of a high standard of data acquisition and in the development of reliable analysis methods. Operation with the real detector has indeed shown differences with the expectations that were used to produce the original data collecting and analysis software, in particular concerning the level and variability of the background due to bioluminescent bursts. To match this aim, the participants to this proposal have chosen to focus their efforts on selected topics related to their fields of expertise both at the level of data collection and data analysis. The studies to be carried out within this project concern the testing and calibration of the detector elements (photomultipliers and front-end electronics), as well as the improvement of methods for data filtering and analysis. They are expected to significantly extend the potentialities of the ANTARES telescope by increasing the detector efficiency and sensitivity. Once the data taking will be optimized, the development of novel analysis techniques will allow full exploitation of the scientific potential of the neutrino telescope. In this context, a significant effort will be put on the search for point sources of cosmic neutrinos, taking profit of the unprecedented sensitivity of the detector. The scientists involved in this proposal are already among the experts in the ANTARES collaboration in the areas described in this document. The funding requested here will enable them to extend their capabilities, both in technical infrastructure and in manpower, in order to achieve the extra scientific effort required by the ANTARES collaboration in this very important phase of development of the experiment. The support provided by this project to the APC group, in particular through the hiring of a post-doc, will be crucial to reinforce its visibility at all levels of the experiment, from the detector instrumentation to the data analysis and interpretation.