Architecture and performance of the KM3NeT front-end firmware
The authors acknowledge the financial support of the funding agencies: Agence Nationale de la Recherche (contract ANR-15-CE31-0020), Centre National de la Recherche Scientifique (CNRS), Commission Europeenne (FEDER fund and Marie Curie Program), Institut Universitaire de France (IUF), LabEx UnivEarthS (ANR-10-LABX-0023 and ANR-18-IDEX-0001), Paris Ile-de-France Region, France; Shota Rustaveli National Science Foundation of Georgia (SRNSFG, FR-18-1268), Georgia; Deutsche Forschungsgemeinschaft (DFG), Germany; The General Secretariat of Research and Technology (GSRT), Greece; Istituto Nazionale di Fisica Nucleare (INFN), Ministero dell'Istruzione, dell'Universita e della Ricerca (MIUR), PRIN 2017 program (Grant NAT-NET 2017W4HA7S) Italy; Ministry of Higher Education Scientific Research and Professional Training, ICTP through Grant AF-13, Morocco; Nederlandse organisatie voor Wetenschappelijk Onderzoek (NWO), the Netherlands; The National Science Centre, Poland (2015/18/E/ST2/00758); National Authority for Scientific Research (ANCS), Romania; Ministerio de Ciencia, Innovacion, Investigacion y Universidades (MCIU): Programa Estatal de Generacion de Conocimiento (refs. PGC2018-096663-B-C41, -A-C42, -B-C43, -B-C44) (MCIU/FEDER), Severo Ochoa Centre of Excellence and MultiDark Consolider (MCIU), Junta de Andalucia (ref. SOMM17/6104/UGR), Generalitat Valenciana: Grisolia (ref. GRISOLIA/2018/119) and GenT (ref. CIDEGENT/2018/034) programs, La Caixa Foundation (ref. LCF/BQ/IN17/11620019), EU: MSC program (ref. 713673), Spain. ; The KM3NeT infrastructure consists of two deep-sea neutrino telescopes being deployed in the Mediterranean Sea. The telescopes will detect extraterrestrial and atmospheric neutrinos by means of the incident photons induced by the passage of relativistic charged particles through the seawater as a consequence of a neutrino interaction. The telescopes are configured in a three-dimensional grid of digital optical modules, each hosting 31 photomultipliers. The photomultiplier signals produced by the incident Cherenkov photons are converted into digital information consisting of the integrated pulse duration and the time at which it surpasses a chosen threshold. The digitization is done by means of time to digital converters (TDCs) embedded in the field programmable gate array of the central logic board. Subsequently, a state machine formats the acquired data for its transmission to shore. We present the architecture and performance of the front-end firmware consisting of the TDCs and the state machine. ; French National Research Agency (ANR) ANR-15-CE31-0020 ; Centre National de la Recherche Scientifique (CNRS) ; Commission Europeenne (FEDER fund), France ; Commission Europeenne (Marie Curie Program), France ; Institut Universitaire de France (IUF), France ; LabEx UnivEarthS, France ANR-10-LABX-0023 ANR-18-IDEX-0001 ; Paris Ile-de-France Region, France ; Shota Rustaveli National Science Foundation of Georgia (SRNSFG), Georgia FR-18-1268 ; German Research Foundation (DFG) ; Greek Ministry of Development-GSRT ; Istituto Nazionale di Fisica Nucleare (INFN) NAT-NET 2017W4HA7S ; Ministry of Education, Universities and Research (MIUR) NAT-NET 2017W4HA7S ; PRIN 2017 program Italy NAT-NET 2017W4HA7S ; Ministry of Higher Education Scientific Research and Professional Training, ICTP, Morocco AF-13 ; Netherlands Organization for Scientific Research (NWO) Netherlands Government ; National Science Centre, Poland 2015/18/E/ST2/00758 ; National Authority for Scientific Research (ANCS), Romania ; Ministerio de Ciencia, Innovacion, Investigacion y Universidades (MCIU): Programa Estatal de Generacion de Conocimiento (MCIU/FEDER), Spain PGC2018-096663-B-C41 PGC2018-096663-A-C42 PGC2018-096663-B-C43 PGC2018-096663-B-C44 ; Severo Ochoa Centre of Excellence and MultiDark Consolider (MCIU), Spain ; Junta de Andalucia European Commission SOMM17/6104/UGR ; Generalitat Valenciana: Grisolia program, Spain GRISOLIA/2018/119 ; Generalitat Valenciana: GenT program, Spain CIDEGENT/2018/034 ; La Caixa Foundation LCF/BQ/IN17/11620019 ; EU: MSC program, Spain 713673