KM3NeT/ARCA sensitivity to transient neutrino sources

The KM3NeT Collaboration is constructing a km3-volume neutrino telescope in the Mediterranean sea, ARCA (Astroparticle Research with Cosmics in the Abyss), for the detection and subsequent study of high-energy cosmic neutrinos.This telescope will be able to reconstruct the arrival direction of the neutrinos with a precision of ~0.1 degrees. The configuration of ARCA makes it sensitive to neutrinos in a wide energy range, from sub-TeV up to tens of PeV. Moreover, this detector has a large field of view and a very high duty cycle, allowing a full-sky (and all-flavours) searches. All these features make ARCA an excellent candidate to study transient neutrino sources. Atmospheric muons and neutrinos, produced by primary cosmic rays, constitute the main background for ARCA. This background can be several orders of magnitude higher than the expected cosmic neutrino flux. In this work, we introduce an event selection which reduces the background up to a negligible level inside the region of interest and within the search time window. The ARCA performance to detect a transient neutrino flux, including the effective area, sensitivity and discovery potential, are provided for a given test source, and for different time windows.