One of the primary goals for ANTARES is the identification of neutrino sources, whose signature would appear in ANTARES data (in form of neutrino arrival directions) as clusters of events at given sky coordinates.
One of the primary goals for ANTARES is the identification of neutrino sources, whose signature would appear as clusters of events at given sky coordinates. The ANTARES data used for this search are therefore a set of reconstructed neutrino arrival directions (in equatorial coordinates: right ascension RA, declination dec).
The significance of a neutrino excess from a given sky position must be assessed over the expected background fluctuations using, for instance the Feldman-Cousins statistics.
The significance of a neutrino excess from a given sky position must be assessed over the expected background fluctuations using, for instance the Feldman-Cousins statistics.
The background is represented by atmospheric neutrinos: neutrinos originating from cosmic ray interactions in the Earth's atmosphere. Their arrival directions are isotropically distributed over the Earth's atmosphere, and result, at the ANTARES detector, uniform in right ascension and with a distribution in declination that depends on the detector geographical position (latitude).
This ANTARES use case allows to inspect a sample of neutrino arrival directions in equatorial coordinates (RA, dec), evaluate from it the expected background rate for a user-selected sky position, and finally assess the significance of a cluster defined as 'all arrival directions that fall inside a given radius, selected by the user and indicated here 'region of interest' (RoI).
This ANTARES use case allows to inspect a sample of neutrino arrival directions in equatorial coordinates (RA, dec), evaluate from it the expected background rate for a user-selected sky position, and finally assess the significance of a cluster defined as 'all arrival directions that fall inside a given radius, selected by the user and indicated here 'region of interest' (RoI).
Here follow the step-by-step description of the code provided as [Jupyter notebook](https://open-data.pages.km3net.de/openscienceportal/notebooks/ANTARES_PointSource)
The background is evaluated in a declination band whose half-width is equal to the RoI radius. The observed 'signal-like' events are those falling inside the RoI. Feldman and Cousins statistics is applied to determine the significance of this observation accounting for the fluctuations expected in the background. The aim of the analysis is set an upper limit, at a given confidence level, on the presence of a source at a given sky position.
Here follows the step-by-step description of the code provided as [Jupyter notebook](https://open-data.pages.km3net.de/openscienceportal/notebooks/ANTARES_PointSource)
