The KM3NeT Collaboration has already produced more than one thousand acquisition boards, used for building two deep-sea neutrino detectors at the bottom of the Mediterranean Sea, with the aim of instrumenting a volume of several cubic kilometers with
light sensors to detect the Cherenkov radiation produced in neutrino interactions. The the so-called Digital Optical Modules, house the PMTs and the acquisition and control electronics of the module, the Central Logic Board, which includes a Xilinx FPGA and embedded soft processor. The present work presents the architecture and functionalities of the software embedded in the soft processor of the Central Logic Board.
A test-bench has been set up at the INFN Sezione di Bologna to optimise key elements of the KM3NeT data acquisition system. A complete framework has been built to simulate a full detection unit and test the optical network, time synchronisation, and
on-shore computing resources. A fundamental tool in the test-setup is a customized electronic board: the OctoPAES. Based on an Altera MAX10 CPLD, it is designed to emulate in a realistic way the optical and acoustic signals recorded by the underwater detectors. They allow to test in extreme conditions the acquisition system and validate its performance with realistic data. If properly configured, the optical data provided by the OctoPAES can be combined to emulate the signals of a through-going muon or other calibration events. In this contribution the OctoPAES boards and some of their use cases at the test-bench are presented.
Since the early days of experimental particle physics photomultipliers (PMTs) have played an important role in the detector design. Thanks to their capability of fast photon counting, PMTs are extensively used in the new-generation of astroparticle p
hysics experiments, such as air, ice and water Cherenkov detectors. Small size PMTs ($leq $ 3 inches diameter) show little sensitivity to the Earth magnetic field, small transit time, stable transit time spread; the price per photocathode area is less comparing to the one for the large area PMTs, typically used so far in such applications. Together with developments and reduced price of multichannel electronics, the use of PMTs of 3-inches or smaller diameter is a promising option even for nowadays large volume detectors. In this paper we report on the design and performance of a new instrument for mass characterisation of PMTs (from 1 inch to 3 inches size), capable to calibrate hundreds of PMTs per day and provide measurements of dark counts, signal amplitude, late-, delayed-, pre- and after-pulses, transit time and transit time spread.
We present new measurements of the total and partial fragmentation cross sections in the energy range 0.3-10 A GeV of 56Fe, 28Si and 12C beams on polyethylene, CR39 and aluminum targets. The exposures were made at BNL, USA and HIMAC, Japan. The CR39
nuclear track detectors were used to identify the incident and survived beams and their fragments. The total fragmentation cross sections for all targets are almost energy independent while they depend on the target mass. The measured partial fragmentation cross sections are also discussed.
SLIM is a large area experiment (440 m2) installed at the Chacaltaya cosmic ray laboratory since 2001, and about 100 m2 at Koksil, Himalaya, since 2003. It is devoted to the search for intermediate mass magnetic monopoles (107-1013 GeV/c2) and nuclea
rites in the cosmic radiation using stacks of CR39 and Makrofol nuclear track detectors. In four years of operation it will reach a sensitivity to a flux of about 10-15 cm-2 s-1 sr-1. We present the results of the calibration of CR39 and Makrofol and the analysis of a first sample of the exposed detector.
We present the calibration of the Makrofol nuclear detector using Pb ions of 158 AGeV.
