ProtoDUNE-DP

ProtoDUNE-DP
Name	ProtoDUNE-DP
Location	CERN, Meyrin
Start	2018
Type	Liquid argon time projection chamber
Field	Particle physics

ProtoDUNE-DP ProtoDUNE-DP was a large-scale prototype detector built at CERN in the Meyrin site to validate technologies for the Deep Underground Neutrino Experiment and the Long-Baseline Neutrino Facility, serving as a milestone between conceptual design and the DUNE far detector. The project brought together institutions including Fermi National Accelerator Laboratory, INFN, University of Bern, and ETH Zurich to test a dual-phase liquid argon time projection chamber concept under realistic cryogenic, readout, and calibration conditions. ProtoDUNE-DP operated within the framework of the CERN Neutrino Platform and interacted with global neutrino efforts such as NOvA, T2K, and ICARUS through shared techniques and cross-calibration studies.

Overview

ProtoDUNE-DP was designed to demonstrate charge amplification and extraction using a dual-phase liquid argon design, bridging R&D between smaller testbeds like WA105 and the full-scale DUNE detectors planned for the Sanford Underground Research Facility near Lead, South Dakota. The prototype was situated in the EHN1 hall at CERN Meyrin and operated alongside ProtoDUNE-SP initiatives to compare single-phase and dual-phase approaches, informing decisions by collaboration boards such as the DUNE Collaboration and advisory bodies like the Neutrino Panel. The program interfaced with technologies under development at Brookhaven National Laboratory, Lawrence Berkeley National Laboratory, and university groups at Università di Padova and Université de Genève.

Detector Design and Technology

The detector implemented a vertical drift dual-phase architecture featuring a cryostat based on commercial membrane cryostat technology developed by industrial partners and tested with instrumentation from CERN and FNAL. Key components included a large-area charge readout plane assembled from LEM (Large Electron Multiplier) devices developed in collaboration with groups from ETH Zurich and Università di Milano, a cryogenic photodetection system using PMT arrays provided by teams at IFAE and CIEMAT, and field-cage structures informed by designs from ICARUS and MicroBooNE. The project tested high-voltage feedthroughs inspired by concepts from ARGONTUBE and employed purification systems similar to those used at SNOLAB and the Gran Sasso National Laboratory for maintaining electron lifetimes.

Construction and Operation

Construction required coordination among industrial contractors, facility engineers at CERN Accelerator and Technology Sector, and detector groups from institutions such as Universidad Autónoma de Madrid, University of Manchester, and University of Oxford. The cryostat and detector assembly proceeded under safety frameworks analogous to those used for LHC detector upgrades, and installation leveraged tooling and logistics practiced during ATLAS and CMS campaigns. Commissioning involved cryogenic cooldown, high-voltage ramping, and laser and radioactive source calibration campaigns developed with input from Institut de Física d'Altes Energies and PSI. Operation phases included cosmics runs and beam tests coordinated with the CERN SPS schedule and controls integrated with the CERN Control Centre.

Data Acquisition and Analysis

The data acquisition system combined cold front-end electronics with warm digitizers and a DAQ architecture patterned after efforts at Fermilab and Lawrence Livermore National Laboratory, integrating firmware from groups at University of Glasgow and software frameworks adopted from artdaq and ROOT-based pipelines. Event reconstruction exploited algorithms for charge extraction, hit finding, and 3D track reconstruction developed in collaboration with computing centers including CERN IT, GridPP, and the Open Science Grid. Analysis chains enabled studies of signal-to-noise, electron lifetime, and ionization yield, cross-checked using calibration samples from cosmic ray muons, laser calibration systems, and tagged sources deployed by teams from Universidad de Granada and Université de Genève.

Results and Impact

ProtoDUNE-DP produced critical measurements of charge amplification, extraction efficiency, and long-range drift stability that influenced design choices for the DUNE far detector modules, informing cost, risk, and schedule assessments reviewed by the Fermilab Directorate and the CERN Council. Performance results were compared with simulations developed using toolkits from Geant4 and electronics noise models validated against data from MicroBooNE and ICARUS. The experiment advanced technologies such as large-area LEM tiling, cryogenic electronics, and membrane cryostat integration, feeding into procurement and engineering baselines used by vendors and agencies including DOE and INFN. Publications and conference presentations at venues like Neutrino 2018 and ICHEP disseminated findings to collaborations including Hyper-Kamiokande and the JUNO community.

Collaboration and Project Management

The ProtoDUNE-DP effort was coordinated by a collaboration council comprising representatives from national laboratories and universities such as Fermilab, CERN, INFN, ETH Zurich, Università di Padova, and University of Bern, operating under governance documents modeled on those of the DUNE Collaboration and reporting to program managers at CERN Neutrino Platform and the DOE Office of Science. Project management employed earned-value techniques and design reviews analogous to those used in major projects like LHC experiments, with technical coordination from institutes including CIEMAT and IFIC. Outreach and training elements connected students and postdoctoral researchers from partner universities to long-baseline neutrino program efforts, shaping workforce development strategies relevant to future detectors at the Sanford Lab.

Category:Neutrino experiments