Neutrinos DUNE

The neutrino group at IP2I has a long-standing expertise in neutrino oscillations physics and in detector developments. It is currently focused on the Deep Underground Neutrino Experiment (DUNE), to which it is contributing since its early stages in 2014 before the birth of the DUNE collaboration.

The discovery of neutrino oscillations, awarded by the Nobel Prize for physics in 2015, provides today the only evidence in elementary particle physics for physics beyond the Standard Model. The DUNE experiment, hosted at the Long Baseline Neutrino Facility in the USA, is going to address fundamental aspects of neutrino mixing and mass ordering and to search for CP violation in the neutrino sector. CP violation in neutrinos could provide a possible explanation of the matter-antimatter asymmetry observed in the today’s universe.

DUNE will exploit a muonic neutrino beam travelling for 1300km in the earth crust, from Fermilab to the Sanford Underground Research Facility, where a detector composed of four 10 kton liquid argon Time Projection Chambers is located 1500m underground. Another detector at Fermilab measures the neutrino beam after its production. The comparison allows demonstrating changes in the neutrino beam, and measuring neutrino oscillation parameters. The beam can be made of neutrinos or of anti-neutrinos, allowing to search for CP violation in neutrino oscillations and performing the determination of the neutrino mass hierarchy, thanks to the matter effects on neutrino oscillations occurring in the earth crust.

DUNE will search as well for rare phenomena, foreseen by Grand Unification theories, such as proton decay and neutron-antineutron oscillations. It will also study cosmic and solar neutrinos, and will look at neutrino bursts from supernovae with unprecedented statistics, time accuracy and neutrino identification sensitivity.

The IP2I neutrino group has been carrying on since 2006 an intensive R&D program on the readout of liquid argon TPC detectors, also supported by the LABEX LIO. It made important contributions to DUNE and the protoDUNE dual-phase prototype at the CERN Neutrino Platform.

The IP2I group intensively carries on several experimental activities on the Liquid argon TPC charge readout R&D; the long-baseline neutrino oscillations experiment DUNE in the USA and the ProtoDUNE dual-phase (NP02) experiment at CERN.

Liquid argon TPC charge readout R&D

Since 2006, the IP2I neutrino group has been carrying on, with the support of the IP2I technical services, an intensive R&D activity on the charge readout of liquid argon TPC detectors, in preparation of the next generation of long baseline experiments based on large liquid argon neutrino detectors.

This activity has been supported by several R&D programs with the involvement of IN2P3, LAGUNA-LBNO, AIDA-2020 and the LABEX LIO. The R&D program includes several axes:

• development of cryogenic ASIC amplifiers
• development of cheap high-bandwidth digitization electronics in uTCA
• development of the timing system based on the White Rabbit standard
• development of the high bandwidth back-end DAQ system and data storage

The electronics have found many staged applications in the CERN 3x1x1, protoDUNE dual-phase prototypes and in DUNE.

The group benefits for its R&D activities of a complete liquid argon laboratory infrastructure (CCIF-LAr) in situ, unique in France, with a TPC of 300 liters fiducial volume. This laboratory infrastructure was built with the support of the LABEX LIO.

DUNE experiment

The IP2I neutrino group is currently focusing on the DUNE experiment, hosted at the Long Baseline Neutrino Facility (LBNF) under construction in the USA, which is going to address fundamental aspects of neutrino mixing and mass ordering and to search for CP symmetry violation in the neutrino sector.

The group has been contributing to DUNE since its early stages, by having been involved in 2014 to the Interim International Executive Board , which drafted the Letter Of Intent at the origin of the DUNE collaboration. It has been then continuing to contribute in DUNE to the design and development of the liquid argon far detector by working on the dual-phase module design.

The IP2I group has responsibilities in DUNE/protoDUNE dual-phase, in particular with the leadership of the DUNE dual-phase Electronics Consortium and the design and implementation of the charge readout electronics and of the DAQ system in the protoDUNE dual-phase prototype, NP02 experiment at the CERN Neutrino Platform. This system has been designed and tested in view of the DUNE 10kton dual-phase detector module.

The IP2I group carries on as well intensive software developments and analysis activities in DUNE (neutrino oscillation studies and tau neutrino appearance, supernova neutrinos) and contributes to the DUNE Computing organization.

ProtoDUNE dual-phase (NP02 experiment at CERN)

The IP2I group has been contributing to the design, construction, operation, exploitation, and data analysis of protoDUNE dual-phase, by also having provided for this detector the analog charge readout electronics the digitization and timing systems and the DAQ system, which were installed and commissioned in the spring 2019.

This work was the outcome of the systematic R&D program started in 2006. The IP2I design is the baseline in the DUNE TDR by the DP Electronics Consortium for the construction of the dual-phase 10 kton module. What was built for ProtoDUNE-DP is representative of 1/20 of the system needed for a full DUNE module:

• The front-end analog amplifiers with the development of the cryogenics ASICs and the design, production, tests and installation of the cryogenic front-end cards operating at 110K at the bottom of the signal feedthrough chimneys (64 channels/card, 7680 channels in total) and of the associated low voltage distribution system and interface flanges.
• The design, production, tests and installation of the uTCA AMC cards for the signals digitization and the high-bandwidth, Ethernet based, front-end DAQ system (64 channels/card, sampling at 2.5 MHz, 7680 channels in total)
• The design, production, tests and installation of the timing/trigger system, based on a development relying on the White Rabbit standard, including White Rabbit end-nodes integrated in the uTCA system
• The design, production, tests and installation of the DAQ back-end system, including: the network infrastructure, two levels of event building machines, a distributed storage system of 1.5 PB capable of recording 20 GB/s and an online computing farm including 450 cores for the real time fast reconstruction of the events. The hardware deployed in the back-end for the storage system, the computing farm and several DAQ servers was procured in collaboration with CCIN2P3 with a donation made to IP2I
• The development of the online software for the data acquisition from the front-end DAQ to the event building and the software for the management and synchronization of the different components of the back-end system and online computing
• The development of the offline software and the computing organization, in collaboration with CERN, FERMILAB and CCIN2P3, and general support and tools for the data analysis

A subset (1280 channels) of the electronics and DAQ system provided by IP2I had been previously successfully operating in 2016-2017 at CERN on the 3x1x1 dual-phase prototype.