• Coordinator: Roumen Tsenov (UniSofia, Bulgaria)
• Co-coordinator: Joakim Cederkall (Lund University, Sweden)
• Software Coordinator: Budimir Kliček (Ruder Boskovic Institute, Croatia)
• Team members:
  • Mariyan Bogomilov (University of Sofia, Bulgaria)
  • Colin Carlile (University of Uppsala, Sweden)
  • Joakim Cerderkall (Lund University, Sweden)
  • Peter Christiansen (Lund University, Sweden)
  • Marcos Dracos (CNRS, France)
  • Tord Ekelof (Uppsala University, Sweden)
  • George Fanourakis (NCSRD, Greece)
  • Kjell Fransson (Uppsala University, Sweden)
  • Theo Geralis (NCSRD, Greece)
  • Gul Gokbulut (Curukova University, Turkey)
  • Aysel Kayis Topaksu (Cukurova University, Turkey)
  • Budimir Klicek (IRB, Croatia)
  • Jason Park (Lund University, Sweden)
  • Georgi Petkov (University of Sofia, Bulgaria)
  • Mario Stipcevic (IRB, Croatia)
  • George Stravopoulos (NCSRD, Greece)
  • Galina Vankova-Kirilova (Unisofia, Bulgaria)

The detectors form an integral and crucial part of any neutrino oscillation facility, and this is not different for ESSνSB. Indeed, the physics reach of the facility depends upon the detector performance, while the event rate, in turn, depends both on the beam intensity from the accelerator and the detector mass. As a result, it is necessary to include the expected detector performance and cost into the design study and to detail that in the CDR. A Water Cherenkov detector (of MEMPHYS type), as opposed, for example, to a liquid argon detector, is a preferable choice for a “low” energy Super Beam such as that generated by the ESSνSB. The lower neutrino cross-sections at lower energies require a detector mass as large as possible. On the other hand, for such low energies there will be less resonant and inelastic multi-prong events, which alleviates the need for detailed pattern recognition capability. This WP will consider the implementation of a megaton scale far Water Cherenkov detector already studied by other projects such as LAGUNA, located in the selected mine, and will estimate its performance using simulations, for both signal efficiency and purity requirements against backgrounds. The benefits of the presence of a near detector to reduce the systematic errors will be studied. The design of such near detector will be elaborated and tested by simulations. Tests to be done in the future will be proposed at CERN using charged particle beams in order to fully understand the detection efficiency of the proposed design, in particular for its utilisation to measure low energy neutrino cross-sections. This WP will also take care of the investigation of the mine issues and subcontracted civil engineering studies.