DUNE Glossary

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z #

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Alternating Current; when used in the phrase "AC coupling" refers to a circuit element that filters out low-frequency components, such as constant offsets, leaving higher frequency signal components. The frequency filtering is determined both by a resistor and a capacitor.
activation time stamp.
analog-to-digital converter
A sampling of a voltage resulting in a discrete integer count corresponding in some way to the input.
A model for hadronization of non-resonant inelastic neutrino reactions used in GENIE. At low invariant hadronic masses, typically less than 2.3 GeV/c2, it is a KNO-inspired empirical model anchored on several bubble chamber measurements of neutrino-induced shower characteristics. For invariant hadronic masses between 2.3 and 3.0 GeV/c2, the model transitions linearly to a GENIE-tuned version of PYTHIA, which is also used for the simulation of events at higher invariant masses.
Authority Having Jurisdiction
An organization, office, or individual responsible for enforcing the requirements of a code or standard, or for approving equipment, materials, an installation, or a procedure (OSHA).
American Iron and Steel Institute.
as low as reasonably achievable
Typically used with regard management of radiation exposure but may be used more generally. It means making every reasonable effort to maintain e.g., exposures, to as far below the limits as practical, consistent with the purpose for that the activity is undertaken.
A Large Ion Collider Experiment, at CERN.
advanced mezzanine card
Holds digitizing electronics and lives in μTCA crates.
analog and mixed signal
Verilog-AMS is a derivative of the Verilog hardware description language that includes analog and mixed-signal extensions (AMS) in order to define the behavior of analog and mixed-signal systems.
Argonne National Laboratory
US national laboratory in Lemont, IL.
anode plane assembly
A unit of the SP detector module containing the elements sensitive to ionization in the LAr. It contains two faces each of three planes of wires, and interfaces to the cold electronics and photon detection system.
authorship and publications board.
A PDS design that consists of a light trap that captures wavelength-shifted photons inside boxes with highly reflective internal surfaces until they are eventually detected by SiPM detectors or are lost.
a light detector ArgonCube effort.
The name of the core part of the DUNE ND, a LArTPC.
The ArgoNeuT test-beam experiment and LArTPC prototype at Fermilab.
A software framework implementing an event-based execution paradigm.
A data acquisition toolkit for data transfer, aggregation and processing.
Ash River
The Ash River, Minnesota, USA NOvA experiment far site, used as an assembly test site for DUNE.
application-specific integrated circuit.
Advanced Telecommunications Computing Architecture
An advanced computer architecture specification developed for the telecommunications, military, and aerospace industries that incorporates the latest trends in high-speed interconnect technologies, next-generation processors, and improved reliability, availability and serviceability.
One of two general-purpose detectors at the LHC. It investigates a wide range of physics, from the measurements of the Higgs boson properties to searches for extra dimensions and particles that could make up DM.
astronomical unit.
acceptance for use and possession
Required for beneficial occupancy of the underground areas at SURF for LBNF and DUNE.
American wire gauge
U.S. standard set of non-ferrous wire conductor sizes.


baryon number
A quantity expressing the total number of baryons in a system minus the number of antibaryons.
boosted dark matter
A new model that describes a relativistic dark matter particle boosted by the annihilation of heavier dark matter particles in the galactic center or the sun.
boosted decision tree
A method of multivariate analysis.
A sequence of control and monitoring devices used for the formation of a directed collection of particles.
Belle II
B-factory experiment now running at KEK.
building management system
Part of the safety system at SURF that includes the fire and life safety system.
Brookhaven National Laboratory
US national laboratory in Upton, NY.
baryon-number violating
Describing an interaction where baryon number is not conserved.
bottom FC
bottom field cage
The horizontal portions of the SP FC on the bottom of the TPC.
Bump On Wire
A working name for the front-end readout computing elements used in the nominal DAQ design to interface the DP crates to the DAQ front-end computers.
branching ratio
A fractional probability for a decay of a composite particle to occur into some specified set or sets of products.
building and site infrastructure
The work package for outfitting of the LBNF underground infrastructure.
beyond the standard model.
Neutrino experiment that operated at the Bugey nuclear power plant in France.


Cabibbo angle
A quark mixing parameter that governs the coupling of up quarks to strange quarks.
Common Analysis File Analysis.
Calibration and Cryogenic Instrumentation.
Experimental program sited at LANL that is designed to make measurements of scientific importance to LBL neutrino physics and physics topics that will be explored by large underground detectors.
charge and time integrated readout chip
A complete read-out chip manufactured in AustriaMicroSystem designed to read arrays of 16 photomultipliers.
charged current
Refers to an interaction between elementary particles where a charged weak force carrier (W+ or W) is exchanged.
configuration change command.
code of conduct committee.
charged current quasielastic interaction
An interaction where a neutrino scatters from a nucleon, producing a charged lepton and converting a neutron to a proton or vice versa.
conceptual design report
A formal project document that describes the experiment at a conceptual level.
conceptual design review
A project management device by which a conceptual design is reviewed.
cold electronics
Analog and digital readout electronics that operate at cryogenic temperatures.
European Organization for NuclearResearch
The leading particle physics laboratory in Europe and home to the ProtoDUNEs. (In French, the Organisation Européenne pour la Recherche Nucléaire, derived from Conseil Européen pour la Recherche Nucléaire).
conventional facilities
Pertaining to construction and operation of buildings and conventional infrastructure, and for LBNF/DUNE, CF includes the excavation caverns.
computational fluid dynamics
High performance computer-assisted modeling of fluid dynamical systems.
cryogenic instrumentation and slow controls
Includes equipment to monitor all detector components and LAr quality and behavior, and provides a control system for many of the detector components.
cryogenic instrumentation test facility
A facility at Fermilab with small (<1 ton) to intermediate (1 ton) volumes of instrumented, purified TPC-grade LAr, used for testing devices intended for use in DUNE.
CKM matrix
Cabibbo-Kobayashi-Maskawa matrix
Refers to the matrix describing the mixing between mass and weak eigenstates of quarks.
confidence level
Refers to a probability used to determine the value of a random variable given its distribution.
CEBAF Large Acceptance Spectrometer
A nuclear and particle physics detector located in the experimental Hall B at Jefferson Laboratory in Newport News, Virginia, United States. It is used to study the properties of the nuclear matter by the collaboration of over 200 physicists. Of particular relevance is its study of electron interactions with nuclei, including argon.
CMake is an open-source, cross-platform family of tools designed to build, test and package software.
construction manager/general contractor
The organizational unit responsible for management of the construction of conventional facilities at the underground area at the SURF site.
Complementary metal-oxide-semiconductor.
configuration management plan.
Compact Muon Solenoid experiment at CERN.
convolutional neural network
A deep learning technique most commonly applied to analyzing visual imagery.
carbon nitrogen oxygen
The CNO cycle (for carbon-nitrogen-oxygen) is one of the two known sets of fusion reactions by which stars convert hydrogen to helium, the other being the proton-proton chain reaction (pp-chain reaction). In the CNO cycle, four protons fuse, using carbon, nitrogen, and oxygen isotopes as catalysts, to produce one alpha particle, two positrons and two electron neutrinos.
cluster on board
An ATCA motherboard housing four RCEs.
A newly developed 16-channels ASIC providing analog to digital conversion.
A 64-channel control and communications ASIC.
common fund
The shared resources of the collaboration.
CORE contributions are in either monetary units or labor hours. They can be technical components for the facility or experiment and the effort of the staff needed to produce, install, and test them; major facilities for the experiment; or other products and services relevant for the completion of the facility or experiment.
commercial off-the-shelf
Items, typically hardware such ascomputers, that may be purchased whole, without any custom design or fabrication andthus at normal consumer prices and availability.
charge parity
Product of charge and parity transformations.
cathode plane assembly
The component of the SP detector module that provides the drift HV cathode.
A pair of CPA panels and the top and bottom FC portions that attach to the pair; an intermediate assembly for installation into the SP module.
charge, parity, and time reversal symmetry
product of charge, parity and time-reversal transformations.
charge-parity symmetry violation
Lack of symmetry in a system before and after charge and parity transformations are applied. For CP symmetry to hold, a particle turns into its corresponding antiparticle under a charge transformation, and a paritytransformation inverts its space coordinates, i.e. produces the mirror image.
collaboration resources board.
Compact Reconfigurable Input Output.
charge readout
The system for detecting ionization charge distributions in a DP detector module.
charge-readout plane
In the DP technology, a collection of electrodes in a planar arrangement placed at a particular voltage relative to some applied E field such that drifting electrons may be collected and their number and time may be measured.
cosmic-ray tagger
Detector external to the TPC designed to tag TPC-traversing cosmic ray particles.
Integrated ASIC including FE circuitry providing signal amplification and pulse shaping, analog to digital conversion, and control and communication functionalities for 64 channels.
computing and software consortium
DUNEcomputing and software consortium.
coefficient of thermal expansion.
Cryogenic Test System.
coating, testing and storage facility
A facility where the the DP photon detectors will be coated, tested, and stored.
beryllium copper, used to make SP APA readout planes.
central utility cavern
The utility cavern at the 4850L of SURF located between the two detector caverns. It contains utilities such as central cryogenics and other systems, and the underground data center and control room.
CERN VM File System
A distributed file system designed for scalable, high-performance distribution of software to interactive and batch computers.
convolutional visual network
An algorithm for identifying neutrino interactions based on their topology and without the need for detailed reconstruction algorithms.


digital-to-analog converter.
Detector electronics for Acquiring PHotons from NEutrinos is a custom-developed warm front-end waveform digitizing electronics module derived from the readout system developed at Fermilab for the Mu2e experiment.
data acquisition
The data acquisition system accepts data from the detector FE electronics, buffers the data, performs a trigger decision, builds events from the selected data and delivers the result to the offline secondary DAQ buffer.
DAQ back-end subsystem
The portion of the DAQ that is generally toward its output end. It is responsible for accepting and executing trigger commands and marshaling the data they address to output storage buffers.
DAQ primary buffer
The portion of the DAQ front-end fragment that accepts full data stream from the corresponding detector unit and retains it sufficiently long for it to be available to produce a data fragment.
DAQ control, configuration and monitoring subsystem
A system for controlling, configuring and monitoring other systems in particular those that make up the DAQ where the CCM encompasses RC.
data flow orchestrator
The process by which trigger commands are executed in parallel and asynchronous manner by the back-end output subsystem of the DAQ.
discovery and presence
As used in the context of the IPC, a system that provides mechanisms for a node on a communication network to learn of the existence of peers and their identity (discovery) as well as determine if they are currently operational or have become unresponsive (presence).
DAQ data receiver
The portion of the DAQ front-end fragment that accepts data from the FER, emits trigger candidates produced from the input trigger primitives, and forwards the full data stream to the DAQ primary buffer.
data selector
The portion of the DAQ front-end fragment that accepts trigger commands and returns the corresponding data fragment. Not to be confused with data selection.
data selection
The process of forming a trigger decision for selecting a subset of detector data for output by the DAQ from the content of the detector data itself. Not to be confused with data selector.
DAQ data selection subsystem
The subsystem of the DAQ responsible for forming a trigger decision based on a portion of the input data stream. The majority subset of the DAQ TS.
external trigger interface
Interface between MTLs and external source and sinks of relevant trigger information.
DAQ front-end readout
The portion of a DAQ front-end fragment that accepts data from the detector electronics and provides it to the DAQ FEC.
DAQ front-end fragment
The portion of one DAQ partition relating to a single DAQ FEC and corresponding to an integral number of detector units. See also data fragment.
OOB dispatcher
out-of-band trigger command dispatcher
This component is responsible for dispatching a SNB dump command to all FERs in the far detector module.
DAQ partition
A cohesive and coherent collection of DAQ hardware and software working together to trigger and read out some portion of one detector module; it consists of an integral number of DAQ front-end fragments. Multiple DAQ partitions may operate simultaneously, but each instance operates independently.
DAQ readout subsystem
The subsystem of the DAQ for accepting and buffering data input from detector electronics.
DAQ readout unit
The first element in the data flow of the DAQ.
DAQ run
A period of time over which relevant data taking conditions and DAQ configuration are asserted to be unchanged. Multiple DAQ runs may occur simultaneously when multiple DAQ partitions are active. This term should not be confused with DUNE experiment or beam "runs" that typically span many DAQ runs.
DAQ run number
A monotonically increasing count that uniquely and globally identifies a DAQ run.
DAQ trigger subsystem
The subsystem of the DAQ responsible for forming a trigger decision.
DAQ timing and synchronization subsystem
The portion of the DAQ that provides for timing and synchronization to various components.
upstream DAQ buffer interface
The process which provides read-only access to data residing in the upstream DAQ buffers to processes on the network.
data fragment
A block of data read out from a single DAQ front-end fragment thatspan a contiguous period of time as requested by a trigger command.
Daya Bay
a neutrino-oscillation experiment in Daya Bay, China, designed to measure the mixing angle Θ13 using antineutrinos produced by the reactors of the Daya Bay and Ling Ao nuclear power plants.
direct coupling.
A distributed, highly scalable (multi-PB) storage system, usable as both a standalone system and as a high-speed frontend to a tape storage system (such as /pnfs at Fermilab).
DUNE construction database
Database used by DUNE to track the history and testing of all parts of each far detector module.
Distributed Communications System.
DUNE detector safety system
The hardware system responsible for the safety of the detector, implemented either via a PLC or via custom hardware protections.
far detector module
The entire DUNE far detector is segmented into four modules, each with a nominal 10 fiducial mass.
detector unit
A portion of a far detector module may be further partitioned into a number of similar parts. For example, the SP TPC is made up of APA units (and other elements).
Computing workflow management designed for LHCb and now used by many HEP experiments.
deep inelastic scattering
Refers to interaction between elementary particles and a nucleus in an energy range where the interaction can be modeled as occurring between constituent quarks of one nucleon and resulting in no bulk recoil of the resulting nucleus.
secondary DAQ buffer
A secondary DAQ buffer holds a small subset of the full rate as selected by a trigger command. This buffer also marks the interface with the DUNE Offline.
dark matter
The term given to the unknown matter or force that explains measurements of galaxy motion that are otherwise inconsistent with the amount of mass associated with the observed amount of photon production.
data management plan.
differential non-linearity
A commonly used measure of performance in ADCs. The DNL error is defined as the difference between an actual step width and the ideal value of one LSB.
Document DataBase
A computerized document management system developed and supported at Fermilab in which virtually all LBNF and most DUNE documents are managed (docs.dunescience.org).
U.S. Department of Energy.
critical decision
The U.S. DOE’s Order 413.3B outlines a series of staged project approvals, each of which is referred to as a critical decision (CD).
data organization, management, and access
data organization, management, and access efforts through the HEP Software Foundation.
Distinguishes one of the DUNE far detector technologies by the fact that it operates using argon in both gas and liquid phases; sometimes called double-phase.
DP module
dual-phase DUNE FD module.
data quality monitoring
Analysis of the raw data to monitor the integrity of the data and the performance of the detectors and their electronics. This type of monitoring may be performed in real time, within the DAQ system, or in later stages of processing, using disk files as input.
dynamic random access memory
A computer memory technology.
(1) refers to electron drift under the influence of an electric field in a TPC; (2) an excavated horizontal corridors (tunnels) in the underground areas at SURF.
diffuse supernova neutrino background
The term describing the pervasive, constant flux of neutrinos due to all past supernova neutrino bursts.
detector support system
The system of rails suspended from the cryostat ceiling in a SP module used to support the APAs, CPAs, and the endwall FCs.
DAQ dump buffer
This DAQ buffer accepts a high-rate data stream, in aggregate, from an associated portion of a far detector module sufficient to collect all data likely relevant to a potential SNB.
Deep Underground Neutrino Experiment
A leading-edge, international experiment for neutrino science and proton decay studies.
DUNE Precision Reaction-Independent Spectrum Measurement
a mobile near detector that can perform measurements over a range of angles off-axis from the neutrino beam direction in order to sample many different neutrino energy distributions.
A term in the DUNE lexicon.


Electrons for Neutrinos
A collaboration dedicated to using JLab’s electron-scattering data to deliver improved neutrino-nucleus cross sections.
event builder
A software agent that executes trigger commands for one far detector module by reading out the requested data.
electromagnetic calorimeter
A detector component that measures energy deposition of traversing particles (in the near detector conceptual design).
engineering change request
The first step in the change control process in which a proposed change is described.
engineering document management system
A computerized document management system developed and supported at CERN in which some DUNE documents, drawings and engineering models are managed.
Experimental Facilities Interface Group
The body responsible for the required high-level coordination between the LBNF and DUNE projects.
Experiment Hall North One
Location at CERN of the ProtoDUNE experiments.
electron lifetime
The attachment of electrons drifting through liquid argon to impurity molecules such as oxygen or water is parameterized by an exponential as a function of time with a time constant called the electron lifetime.
emergency management.
electromagnetic interference
Disturbance generated by an external source that affects an electrical circuit by electromagnetic induction, electrostatic coupling, or conduction.
equivalent noise charge
The equivalent noise charge is the input charge that corresponds to a S/N = 1.
effective number of bits
The effective number of bits is a measure of the dynamic range of an ADC and its associated circuitry. The resolution of an ADC is specified by the number of bits used to represent the analog value, in principle giving 2N signal levels for an N-bit signal. However, all real ADC circuits introduce noise and distortion. ENOB specifies the resolution of an ideal ADC circuit that would have the same resolution as the circuit under consideration.
education and outreach committee.
The XRootD-based distributed file system developed by CERN.
emergency response team.
elastic scattering
Events in which a neutrinoelastically scatters off of another particle.
electrostatic discharge.
environment, safety and health
A discipline and specialty that studies and implements practical aspects of environmental protection and safety at work.
European Strategy for Particle Physics
Thecornerstone of Europe’sdecision-making process for the long-term future of thefield. Mandated by the CERN Council, it is formed through a broadconsultation of the grass-roots particle physics community, itactively solicits the opinions of physicists from around the world,and it is developed in close coordination with similar processes inthe USA and Japan in order to ensure coordination between regions andoptimal use of resources globally.
Experiment Test Framework
WLCG testing middleware running grid jobs that actively test distributed sites services and capabilities, and report back to monitoring services.
external trigger logic
Trigger processing that consumes far detector module level trigger notification information and other global sources of trigger input and emits trigger command information back to the MTLs.
earned value management system
Earned Value Management is a systematic approach to the integration and measurement of cost, schedule, and technical (scope) accomplishments on a project or task. It provides both the government and contractors the ability to examine detailed schedule information, critical program and technical milestones, and cost data (text from the US DOE); the EVMS is a system that implements this approach.
endwall FC
endwall field cage
The vertical portions of the SP FC near the wall.
executive board
The highest level DUNE decision-making body for the collaboration.
The integrated detector fiducial mass times beam intensity; it is proportional to the number of interactions and is used to normalize cross sections in a data sample.
external trigger candidate
Information provided to the MTL about events external to a far detector module so that it may be considered in forming trigger commands.


Fondazione Bruno Kessler
FBK is a research non-profit entity in Trento, Italy that partners in the development of technology with applications in various fields including High Energy Physics.
field cage
The component of a LArTPC that contains and shapes the applied E field.
far detector
The 70 kt total (40 fiducial) mass LArTPC DUNE detector, composed of four LAr mass total (10 kt fiducial) mass modules, to be installed at the far site at SURF in Lead, SD, USA.
final design review
A project management device by which a final design is reviewed.
The front-end refers a point that is "upstream" of the data flow for a particular subsystem. For example the SP front-end electronics is where the cold electronics meet the sense wires of the TPC and the front-end DAQ is where the DAQ meets the output of the electronics.
finite element analysis
Simulation of a physical phenomenon using the numerical technique called Finite Element Method (FEM), a numerical method for solving problems of engineering and mathematical physics.
front-end board.
DAQ front-end computer
The portion of one DAQ partition that hosts the DDR, DAQ primary buffer and data selector. It hosts the FER and corresponding portion of the DAQ primary buffer.
front-end electronics.
Front-End Link eXchange
A high-throughput interface between FE and trigger electronics and the standard PCIe computer bus.
front-end mother board
Refers a unit of the SP CE that contains the FE amplifier and ADC ASICs covering 128 channels.
Fermilab Environment, Safety and Health Manual
The document that contains Fermilab’s policies and procedures designed to manage environment, safety, and health in all its programs.
fast Fourier transform.
forward horn current (νμ mode).
Facility Information Reporting Utility System
The safety system at SURF.
fire and life safety system
Part of the safety system at SURF.
FPGA mezzanine card
Boards holding FPGAs and other integrated circuitry that attach to a motherboard.
Fermi National Accelerator Laboratory
U.S. national laboratory in Batavia, IL. It is the laboratory that hosts DUNE and serves as its near site.
field programmable gate array
Anintegrated circuit technology that allows the hardware to be reconfigured toexecute different algorithms after its manufacture and deployment.
Flame-retardant fiberglass-reinforced epoxy resin laminate used in making PCBs and other detector components.
Fermi Research Alliance
A joint partnership of the University of Chicago and the Universities Research Association (URA) that manages and operates Fermilab on behalf of the DOE.
fiber-reinforced plastic.
full stream
Relates to a data stream that has not undergone selection, compression or other form of reduction.
far site conventional facilities
The CF at the DUNE far detector site, SURF.
final-state interactions
Refers to interactions between elementary or composite particles subsequent to the initial, fundamental particle interaction, such as may occur as the products exit a nucleus.
field shaping strips.
full-time equivalent. A unit of labor for the project. One year of work from one person.
File Transfer System
A file transfer system developed at Fermilab to catalog and move data to permanent storage.
Light-weight version of the Fermilab File Transfer system used for rapid data transfers out of the online systems.
fiducial volume
The detector volume within the TPC that is selected for physics analysis through cuts on reconstructed event position.
full width at half maximum
Width of a distribution measured between those points at which the distribution is equal to half of its maximum amplitude.


Non-flame-retardant fiberglass-reinforced epoxy resin laminate used in making PCBs.
gaseous argon
argon in its gas phase.
gaseous argon time-projection chamber
A TPC filled with gaseous argon; a possible technology choice for the ND.
geometry description markup language
An application-indepedent, geometry-description format based on XML.
A software toolkit for the simulation of the passage of particles through matter using MC methods.
Generates Events for Neutrino Interaction Experiments
Software providing an object-oriented neutrino interaction simulation resulting in kinematics of the products of the interaction.
ground grid
An electrode held electrically neutral relative to Earth ground voltage; it is installed between the cathode and the PDs in a DP module to protect the PMTs, maintaining high transparency to light.
Giessen Boltzmann-Uehling-Uhlenback Project; a unified theory and transport framework in the MeV and GeV energy regimes for elementary reactions on nuclei.
General Long-Baseline Experiment Simulator
A software package for simulating energy spectra of neutrino flux, interactions, and energy spectra measured after application of some model of a detector response).
grounding mesh
A metal mesh attached to the SP APA frame between the collection-plane wires and the space inside the frame where the PD modules are installed. It provides electric field uniformity so the collection-plane wires all have similar fields around them.
ground plane
An electrode held electrically neutral relative to Earth ground voltage; it is mounted on the FC in a SP module to protect the cryostat wall.
general purpose interface bus.
grid plane
The uninstrumented plane of wires in a SP APA that borders the drift volume. It shapes the signals and provides ESD protection.
Global Positioning System
A satellite-based system that provides a highly accurate 1PPS signal that may be used to synchronize clocks and determine location.
GSC group
global safety coordination group
DUNE group that evaluates applicable codes and standards, including international code equivalency, for the design, assembly, and installation of the FD.
grand unified theory
A class of theories that unifies the electroweak and strong forces.


hazard analysis
A first step in a process to assess risk; the result of hazard analysis is the identification of the hazards present for a task or process.
invariant mass of the hadronic system
Refers to the invariant mass of the hadronic system formed during the neutrino scatter.
hazard analysis report.
high-density polyethylene
A thermoplastic polymer made from petroleum commonly used to make plastic bottles.
high energy physics.
High Efficiency Particulate Air
The High Efficiency Particulate Air filters are a type of air filter that remove 99.97% of particles that have a size greater than or equal to 0.3 μm.
high-level trigger
This is actually a filter applied to data that has been triggered and aggregated in order to further reduce or characterize it.
high-performance computing
high-performance computing facilities; generally computing facilities emphasizing parallel computing with aggregate power of more than a teraflop.
high-pressure gas
gas at high pressure to be used in a HPgTPC.
high-pressure gaseous argon TPC
A TPC filled with gaseous argon; a possible component of the DUNE ND.
HEP Software Foundation Collaboration
A foundation that facilitates cooperation and common efforts in high energy physics software and computing internationally.
High Throughput Computing
Computing facilities typically consisting of large numbers of commodity servers as opposed to a single large machine. Best suited for running large numbers of independent jobs in parallel, these facilities are what is usually meant by "grid computing".
high voltage
Generally describes a voltage applied to drive the motion of free electrons through some media, e.g., LAr.
HV divider board.
HV power supply.
high voltage system
The detector subsystem that provides the TPC drift field.
Hyper Kamiokande
260 kt water Cerenkov neutrino detector to begin construction at Kamiokande in 2020.


Inter-Integrated Circuit
I2C or I2C is a synchronous,multi-master, multi-slave, packet switched, single-ended, serial computer bus widely usedfor attaching lower-speed peripheral ICs to processors and microcontrollers in short-distance,intra-board communication.
institutional board.
A neutrino experiment that was located at the Laboratori Nazionali del Gran Sasso (LNGS) in Italy, then refurbished at CERN for re-use in the same neutrino beam from Fermilab used by the MiniBooNE , MicroBooNE and SBND experiments. The ICARUS detector is being reassembled at Fermilab.
ICEBERG R&D cryostat and electronics
Integrated Cryostat and Electronics Built for Experimental Research Goals: a new double-walled cryostat built and installed at Fermilabfor liquid argon detector R&D and for testing of DUNE detector components.
inner diameter
Inner diameter of a tube.
integrated environmental, safety and health plan.
Database that stores beamline information indexed by timestamp.
Intensity Frontier Data Handling
The actual command invoked when using IFDHC, on the command line, e.g. ifdh cp source_file dest_file.
Intensity Frontier Data Handling Client
A multi-protocol tool for data transfer and file delivery in jobs. It is able to automatically select transfer protocols based on source and destination characteristics.
Instituto de Fisica Corpuscular (in Valencia, Spain).
inverted hierarchy
Refers to the neutrino mass eigenstate ordering whereby the sign of the mass squared difference associated with the atmospheric neutrino problem is negative.
integrated master schedule
A project management device consisting of linked tasks and milestones.
Intranuclear momentum transfer.
International Neutrino Council
A highest-level international advisory body to the U.S. DOE and the Fermilab directorate on matters related to the LBNF and the PIP-II projects. This council is composed of representatives from the international funding agencies and CERN that make major contributions the infrastructure.
Web-based meeting organization tool.
integral non-linearity
A commonly used measure of performance in ADCs. It is the deviation between the ideal input threshold value and the measured threshold level of a certain output code.
integration office
The office that incorporates the onsite team responsible for coordinating integration and installation activities at SURF.
inverted ordering
Refers to the neutrino mass eigenstate ordering whereby the sign of the mass squared difference associated with the atmospheric neutrino problem is negative.
interval of validity
Interval over which something is valid.
inter-process communication
A system for software elements to exchange information between threads, local processes or across a data network. An IPC system is typically specified in terms of protocols composed of message types and their associated data schema.
project integration director
Responsible for integration and installation of LBNF and DUNE deliverables in South Dakota. Manages the integration office.
institutional board representative.
inter-range instrumentation group
A standards body that defined a time-code standard for transferring timing information.
inner readout chamber
inner (radial) readout chamber for gaseous argon TPC.
installation readiness review
A project management device by which the plan for installation is reviewed.


Joint Project Office
The framework through which team members from the LBNF project office, integration office, and DUNE technical coordination work together to provide coherence in project support functions across the global enterprise.Its functions include global project configuration and integration, installation planning and coordination, scheduling, safety assurance, technical review planning and oversight, development of partner agreements, and financial reporting.


A polyimide plastic film that is stable over a broad range of temperatures and is resistant to radiation damage.
A strong authentication system used by the computing resources at Fermilab and CERN.
KLOE is a e+e collider detector spectrometer operated at DAFNE, the ϕ-meson factory at Frascati, Rome. In DUNE it will consist of a 26 cm Pb+scintillating fiber ECAL surrounding a cylindrical open detector region that is 4.00 m in diameter and 4.30 m long. The ECAL and detector region are embedded in a 0.6 T magnetic field created by a 4.86 m diameter superconducting coil and a 475 tonne iron yoke.


length-to-energy ratio.
Laboratory Virtual Instrument Engineering Workbench is a system-design platform and development environment for a visual programming language from National Instruments.
Los Alamos National Laboratory
US national laboratory in Los Alamos, NM.
Liquid Argon Purity Demonstrator
Cryostat at Fermilab for long-term studies requiring a large volume of argon.
liquid argon
Argon in its liquid phase; it is a cryogenic liquid with a boiling point of 87 K and density of 1.4 g/ml.
A 16-channel FE ASIC that provides signal amplification and pulse shaping.
The repurposed ArgoNeuT LArTPC, modified for use in a charged particle beam, dedicated to the calibration and precise characterization of the output response of these detectors.
ASIC pixelated charge readout for a TPC.
Liquid Argon Software
A shared base of physics software across LArTPC experiments.
liquid argon time-projection chamber
A TPC filled with liquid argon;the basis for the DUNE FD modules.
LEM-anode Sandwich
In the DP technology, a LEM and its corresponding anode are mounted together in a module called a LEM-anode sandwich.
Refers to the distance between the neutrino source and the FD. It can also refer to the distance between the near and far detectors. The "long" designation is an approximate and relative distinction. For DUNE, this distance (between Fermilab and SURF) is approximately 1300 km.
laser beam location system
Auxiliary calibration system providing an independent location measurement of the ionization laser beams direction.
Long-Baseline Neutrino Committee
The committee, composed of internationally prominent scientists with relevant expertise, charged by the Fermilab director to review the scientific, technical, and managerial progress, plans and decisions associated with DUNE.
Long Baseline Neutrino Experiment (a terminated US project that was reformulated in 2014 under the auspices of the new DUNE collaboration, an internationally coordinated and internationally funded program, with Fermilab as host).
Long-Baseline Neutrino Facility
The organizational entity responsible for developing the neutrino beam, the cryostats and cryogenics systems, and the conventional facilities for DUNE.
LBNF and DUNE project
The overall global project, including LBNF and DUNE.
LBNF Strategic Project Advisory Committee
A committee charged by the host laboratory director to provide expert, independent advice on significant issues and strategies related to LBNF project organization, management, and risks.
Lawrence Berkeley National Laboratory
US national laboratory in Berkeley, CA.
Long Baseline Neutrino Observatory
A terminated European project that, during its six-year duration, assessed the feasibility of a next-generation deep underground neutrino observatory in Europe).
logistics center
A facility where LBNF and DUNE components will be received and transhipped to SURF.
light calibration module.
light-mass dark matter
Refers to dark matter particles with mass values much lower than the electroweak scale, specifically below the 1 GeV level.
Light Dark Matter eXperiment
The LDMX detector concept consists of a small precision tracker, and electromagnetic and hadronic calorimeters, all with near 2π azimuthal acceptance from the forward beam axis out to  ∼ 40 angle. This detector would be capable of measuring correlations among electrons, pions, protons, and neutrons in electron-nucleus scattering at exactly the energies relevant for DUNE physics.
low-dropout regulator
A low-dropout or LDO regulator is a DC linear voltage regulator that can regulate the output voltage even when the supply voltage is very close to the output voltage.
Light-emitting diode.
large electron multiplier
A micro-pattern detector suitable for use in ultra-pure argon vapor; LEMs consist of copper-clad PCB boards with sub-millimeter-size holes through which electrons undergo amplification.
Large Hadron Collider.
LHC experiment dedicated to forward physics.
liquid nitrogen.
liquefied natural gas
Pertaining to natural gas in its liquid phase.
light pulser module.
laser positioning system.
long-range interactions.
light readout
The system for detecting scintillation photons in a DP detector module.
least significant bit
The bit with the lowest numerical value in a binary number.
Liquid Scintilator Neutrino Detector
A scintillation detector and associated experiment located at Los Alamos National Laboratory.
Large Synoptic Survey Telescope
8.4 m telescope with 3.2G-pixel camera that will start taking data in 2023.
Large Underground Xenon (LUX) dark matter detector at SURF.
low voltage.
low-voltage differential signaling.
Experiment sited at SURF that seeks to detect faint interactions between galactic dark matter and regular matter.


Model of Argon Reaction Low Energy Yields
Developed at UC Davis, MARLEY is the first realistic model of neutrino electron interactions on argon for enegies less than 50 MeV. This includes the energy range important for SNB neutrinos and also solar 8–boron neutrinos.
Monte Carlo
Refers to a method of numerical integration that entails the statistical sampling of the integrand function. Forms the basis for some types of detector and physics simulations.
MicroTCA Carrier Hub
An network switching device.
Monte Carlo Particle
Individual true simulated particle.
main communications room
Space at the FD site for cyber infrastructure.
meson-exchange currents
An nuclear effect wherein pairs or larger groups of nucleons within a nucleus are bound together through the exchange of pions or other mesons. Neutrinos and other particles can scatter from these correlated pairs.
mass hierarchy
Describes the separation between the mass squared differences related to the solar and atmospheric neutrino problems (also written as MO).
Fermilab Main Injector
An accelerator at Fermilab that provides a beam of high-energy protons that upon striking a target produce secondaries that decay to provide the neutrinos directed toward the DUNE far detector.
A LArTPC neutrino oscillation experiment at Fermilab.
Neutrino cross sections experiment at Fermilab.
The Mini Booster Neutrino Experiment, at Fermilab, was designed to fully explore the LSND result.
miniature parallel optical device
a family of types of multi-channel optical transceivers.
A long-baseline neutrino experiment, with a near detector at Fermilab and a far detector in the Soudan mine in Minnesota, designed to observe the phenomena of neutrino oscillations (ended data runs in 2012).
The successor to the MINOS experiment, utilizing the same detectors and beam line, but operating at higher beam energy tune than MINOS, parasitic with NOvA.
minimum ionizing particle
Refers to a particle traversing some medium such that the particle’s mean energy loss is near the minimum.
master in slave out
The Master In Slave Out is a logicsignal on the SPI bus on which the data from the slave are transmitted oncea request from the master is received.
Majorana Demonstrator
Experiment sited at SURF that seeks to determine whether neutrinos are their own antiparticles.
module level trigger
The DAQ component responsible for producing a trigger decision that will be used to command the readout of a detector module.
mass ordering
See MH.
Many aspects of the DUNE far and near detectors are modular, so "module" must be understood in context. It may refer to one of the four far detector modules, distinct portions of a subdetector as in a "field cage module," a software or electronics module, e.g., a separate framework plug-in, and so on.
master out slave in
The Master Out Slave In is a logicsignal on the SPI bus on which the data from the master is transmitted.
memorandum of understanding
A document summarizing an agreement between two or more parties.
multi-purpose detector
A component of the near detector conceptual design; it is a magnetized system consisting of a HPgTPC and a surrounding ECAL.
MicroPattern Gas Detectors.
6 mm×6 mm Multi-Pixel Photon Counters produced by Hamamatsu Photonics K.K.
MPT detector
multipurpose tracking detector.
Multi Repository Build System
A Fermilab-developed build system based on that allows development and builds of code from multiple repositories.
Mikheyev-Smirnov-Wolfenstein effect
Explains the oscillatory behavior of neutrinos produced inside the sun as they traverse the solar matter.
module trigger logic
Trigger processing that consumes detector unit level trigger command information and emits trigger commands. It provides the ETL with trigger notifications and receives back any external trigger candidates.
An experiment sited at Fermilab that searches for charged-lepton flavor violation and seeks to discover physics beyond the SM.
multi-wire proportional chamber.


CERN hadron production experiment.
network attached storage
Disk storage that is available on computers but shared between them. Relies on NFS mounts rather than authenticated file transfer protocols. Usually found on interactive servers to provide space for home directories, app and data storage.
U.S. National Aereonautics and Space Administration.
neutral current
Refers to an interaction between elementary particles where a neutrally charged weak force carrier (Z0) is exchanged.
Neutrino Cost Group
A group of internationally prominent scientists with relevant experience that is charged by the Fermilab director to review the cost, schedule, and associated risks for the DUNE experiment.
near detector
Refers to the detector(s) installed close to the neutrino source at Fermilab.
Near Detector 280, is the magnetized near detector .
non-destructive examination.
component of the near detector with a core gaseous argon TPC surrounded by an ECAL and a magnet.
nucleon decay
The hypothetical, baryon number violating decay of a proton or a bound neutron into lighter particles.
LArTPC component of the near detector based on ArgonCube technology.
National Energy Research Computing Facility at LBNL.
neutrino interaction generator
A neutrino interaction simulation program library for the studies of atmospheric accelerator neutrinos.
Enriched Xenon Observatory
Experiment at Lawrence Livermore National Laboratory (U.S. national lab in Livermore, CA) searching for new physics with neutrinoless double-beta decay.
network file system
Industry-standard mechanism for mounting disks over a network. Provides regular UNIX file and directory access.
normal hierarchy
Refers to the neutrino mass eigenstate ordering whereby the sign of the mass squared difference associated with the atmospheric neutrino problem is positive.
network interface controller
Hardware for controlling the interface to a communication network. Typically, one that obeys the Ethernet protocol.
normal ordering
Refers to the neutrino mass eigenstate ordering whereby the sign of the mass squared difference associated with the atmospheric neutrino problem is positive.
The NOvA off-axis neutrino oscillation experiment at Fermilab.
CERN North Area hadron beamline used for the ProtoDUNE-DP test beam run.
CERN North Area hadron beamline used for the ProtoDUNE-SP test beam run.
near site conventional facilities
The CF at the DUNE near detector site, Fermilab.
nonstandard interaction
A general class of theory of elementary particles other than the Standard Model.
Network Time Protocol
A networking protocol that allows synchronizing of clocks to within a few of a time standard on a local network and within a few tens of over the Internet.
NuFIT 4.0
The NuFIT 4.0 global fit to neutrino oscillation data.
a set of facilities at Fermilab, collectively called "Neutrinos at the Main Injector." The NuMI neutrino beamline target system converts an intense proton beam into a focused neutrino beam.
neutrino interaction generator.
Non-volatile memory express
A specification for an interface to storage media attached via PCIe.


Any of the eight parts into which 4π is divided by three mutually perpendicular axes. In particular in referencing the value for the mixing angle θ23.
outer diameter
Outer diameter of a tube.
oxygen deficiency hazard
a hazard that occurs when inert gases such as nitrogen, helium, or argon displace room air and thus reduce the percentage of oxygen below the level required for human life.
online monitoring
Processes that run inside the DAQ on data "in flight," specifically before landing on the offline disk buffer, and that provide feedback on the operation of the DAQ itself and the general health of the data it is marshalling.
Type of multi-mode fiber optic cable, typically capable of 10 Gbps data transmission at lengths up to 300 m.
Type of multi-mode fiber optic cable, typically capable of 10 Gbps data transmission at lengths up to 550 m.
open platform communications
Open platform communications is a series of standards and specifications for industrial telecommunication.
OPC Unified Architecture is a machine to machine communication protocol for industrial automation developed by the OPC Foundation. OPC stands for Object Linking and Embedding for Process Control.
operational readiness clearance
Final safety approval prior to the start of operation.
outer readout chamber
outer (radial) readout chamber for gaseous argon TPC.
operational readiness review
A project management device by which the operational readiness is reviewed.
Open Science Grid
Open Science Grid.
Occupational Safety and Health Administration (USA Department of Labor) formed by the Occupational Safety and Health Act of 1970.


framework used to plan and status the resource-loaded schedule of activities associated with the USA contributions to LBNF and DUNE.
Proton Assembly Building
Home of several LAr facilities at Fermilab.
The Pandora multi-algorithm approach to pattern recognition.
principal component analysis
A statistical procedure that uses an orthogonal transformation to convert a set of observations of possibly correlated variables into a set of values of linearly uncorrelated variables called principal components (Wikipedia).
printed circuit board.
Peripheral Component Interconnect.
photon detector
The detector elements involved in measurement of the number and arrival times of optical photons produced in a detector module.
The DP ProtoDUNE detector at CERN.
Particle Data Group.
a prototype DUNE ND.
preliminary design review
A project management device by which an early design is reviewed.
photon detection system
The detector subsystem sensitive to light produced in the LAr.
The SP ProtoDUNE detector at CERN.
A second test run in the singe-phaseProtoDUNE test stand at CERN, acting as a validation of the finalsingle-phase detector design.
An electron ejected from the surface of a material by the photoelectric effect.
TPC for the Positron Electron Project 4 Collider at Stanford.
Particle Physics Project PrioritizationPanel
The Particle Physics Project Prioritization Panel (P5) was asubpanel of the High Energy Physics Advisory Panel (HEPAP). It completedits Report, a ten-year strategic plan for high energy physics in theU.S., in 2014. This report included a recommendation that "host a world-leading neutrinoprogram that will have an optimized set of short- and long-baseline neutrino oscillation experiments, and its long-term focusis a reformulated venture referred to here as the Long BaselineNeutrino Facility (LBNF)".
particle flow particle
Each of the individual reconstructed particles in the hierarchy (or particle flow) describing the reconstructed event interaction.
steel pickling and oiling is a metal surface treatment finishing process used to remove surface impurities such as rust and carbon scale from hot rolled carbon steel.
particle ID
Particle identification.
Proton Improvement Plan II
A Fermilab project for improving the protons on target delivered delivered by the LBNF neutrino production beam. This is version two of this plan and it is planned to be followed by a PIP-III.
programmable logic controller
An industrial digital computer that has been ruggedized and adapted for the control of manufacturing or other processes that require high reliability, ease of programming, and process fault diagnosis.
Phase-Locked Loop
A control system that generates anoutput signal whose phase is related to the phase of an input signal.
Projection Matching Algorithm
A reconstruction algorithm that combines 2D reconstructed objects to form a 3D representation.
A type of matrix that describes the mixing between mass and weak eigenstates of the neutrino.
photomultiplier tube
A device that makes use of the photoelectric effect to produce an electrical signal from the arrival of optical photons.
Pseudo Network File System
A file system often used in large storage systems. Typically interaction is very similar to a regular NFS volume, but there can be some subtle and important differences.
Type of bipolar junction transistor consistning of alayer of N-doped semiconductor sandwiched between two layers of P-doped material.
pulsed neutron source
Calibration system basedon neutron capture gamma showers spread out in the whole detector.
protons on target
Typically used as a unit of normalization for the number of protons striking the neutrino production target.
parts per billion
A concentration equal to one part in 10 − 9.
personnel protective equipment
Equipment worn to minimize exposure to hazards that cause serious workplace injuries and illnesses.
parts per million
A concentration equal to one part in 10 − 6.
production progress review
A project management device by which the progress of production is reviewed.
1PPS signal
one-pulse-per-second signal
An electrical signal with a fast rise time and that arrives in real time with a precise period of one second.
parts per trillion
A concentration equal to one part in 10 − 12.
preliminary design report
A formal project document that describes the experiment at a preliminary design level.
Either of the two DUNE prototype detectors constructed at CERN. One prototype implements SP technology and the other DP.
The second run of a ProtoDUNE detector.
production readiness review
A project management device by which the production readiness is reviewed.
pressure safety valve.
power and timing backplane
Backplane used to connect the WIBs and the PTCs on the WIEC. Also connects the CE flange on the cryostat penetration.
power and timing card
Cards that provide further processing and distribution of the signals entering and exiting the SP cryostat.
A WLS material.
Precision Time Protocol
A networking protocol that allows synchronizing of clocks to within a few of a time standard on a local network.
publish-subscribe communication pattern
An IPC communication pattern where one element, the publisher, sends data to all connected elements, the subscribers. Each subscriber may connect to multiple publishers. A variant is PUB/SUB with topics where a subscriber may register an identifier, the topic, to limit the information received to just an associated subset.


quality assurance
The set of actions taken to provide confidence that quality requirements are fulfilled, and to detect and correct poor results.
quality assurance manager.
quality assurance plan.
quality control
An aggregate of activities (such as design analysis and inspection for defects) performed to ensure adequate quality in manufactured products.
Refers to the interaction of an elementary charged particle with a nucleus in an energy range where the interaction can be modeled as taking place with individual nucleons.
Quad Flat Package.


resistive-capacitive (circuit).
DAQ event block
The unit of data output by the DAQ. It contains trigger and detector data spanning a unique, contiguous time period and a subset of the detector channels.
run control
The system for configuring, starting and terminating the DAQ.
reconfigurable computing element
Data processor located outside of the cryostat on a COB that contains FPGA, RAM and SSD resources, responsible for buffering data, producing trigger primitives, responding to triggered requests for data and synching SNB dumps.
resource coordinator
A member of the DUNE management team responsible for coordinating the financial resources of the project effort.
readout window
A fixed, atomic and continuous period of time over which data from a far detector module, in whole or in part, is recorded. This period may differ based on the trigger that initiated the readout.
Electrons freed from Argon atoms will sometimes recombine with the positive argon ions, either the same ones from which they came or nearby ones. Sometimes called "quenching".
resonant scattering
The mode of scattering where the target nucleon is excited to a resonant state and decays, typically producing one or more pions.
radio frequency
Electromagnetic emissions that are within the (radio) frequency band of sensitivity of the detector electronics.
reverse horn current (νμ bartonumubar mode).
reconfigurable input output.
risk probabilities
The risk probability, after taking into account the planned mitigation activities, is ranked as L (low < 10 %),M (medium ), orH (high > 25 %).The cost and schedule impacts are ranked asL (cost increase < 5 %, schedule delay < 2 months),M ( and 2–6 months, respectively) andH (> 20 % and > 2 months, respectively).
Resistive MicroMegas.
root mean square
The square root of the arithmetic mean of the squares of a set of values, used as a measure of the typical magnitude of a set of numbers, regardless of their sign.
review office
An office within the integration office that organizes reviews.
readout chamber
readout chamber for gaseous argon TPC.
region of interest.
A modular scientific software toolkit. It provides all the functionalities needed to deal with big data processing, statistical analysis, visualisation and storage. It is mainly written in C++ but integrated with other languages such as Python and R.
resistive panel
Resistive panels form the constant potential surfaces for a SP module CPA; they are composed of a thin layer of carbon-impregnated Kapton and laminated to both sides of a FR-4 sheet.
random phase approximation
an approximation method commonly used for describing the dynamic linear electronic response of electron systems (Wikipedia).
Resources Review Board
A part of DUNE’s international project governance structure, composed of representatives of all funding agencies that sponsor the project, and of Fermilab management, established to provide coordination among funding partners and oversight of DUNE.
radioactive source deployment system
Proposed calibration system based on the deployment ofradioactive sources inside the DUNE cryostat.
resistance temperature detector
A temperature sensor consisting of a material with an accurate and reproducible resistance/temperature relationship.
Data management system originally developedby ATLAS but now open-source and shared across HEP.


signal-to-noise ratio.
spokespersons advisory committee.
SLAC ASIC Control Interface.
sequential access via metadata
A data-handling system to store and retrieve files and associated metadata, including a complete record of the processing that has used the files.
System for on-Axis Neutrino Detection
The beam monitor component of the near detector that remains on-axis at all times and serves as a dedicated neutrino spectrum monitor.
successive approximation register.
Standard ARAPUCA design with different WLS coatings on both faces of the dichroic filter window(s) of the cell.
Another term for the materials airlock; a pass-through chamber used to ensure safe transfer of materials into a clean room, avoiding contamination in both directions.
Short-Baseline Neutrino
A Fermilab program consisting of three collaborations, MicroBooNE, SBND, and ICARUS, to perform sensitive searches for νe appearance and νμ disappearance in the Booster Neutrino Beam.
The Short-Baseline Near Detector experiment at Fermilab.
scientific computing.
supervisory control and data acquisition.
Scientific Computing Infrastructure
Proposedextension of the infrastructure component of WLCG to otherexperiments.
speakers committee.
Fermilab South Dakota Services Division
A Fermilab division responsible providing host laboratory functions at SURF in South Dakota.
South Dakota Science and Technology Authority
The legal entity that manages SURF, in Lead, S.D.
South Dakota Warehouse Facility
Warehousing operations in South Dakota responsible for receiving LBNF and DUNE goods and coordinating shipments to the Ross shaft at SURF.
spurious free dynamic range
Spurious free dynamic range is the ratio of the RMS value of the signal to the RMS value of the worst spurious signal regardless of where it falls in the frequency spectrum. The worst spur may or may not be a harmonic of the original signal.
Super Fine-Grained Detector (SuperFGD) is 3D granular plastic scintillator detector that adopts the same technology as . It will be installed in the system . design will inherit in large part from the SuperFGD detector.
small form-factor pluggable
a particular standard for optical transceivers.
signal feedthrough
A cryostat penetration allowing for the passage of cables or other extended parts.
SFT chimney
signal feedthrough chimney
In the DP technology, a volume above the cryostat penetration used for a signal feedthrough.
add def (DP install).
A vertical excavation at SURF connecting with the surface.
safe high voltage
Type of bayonet mountconnector used on coaxial cables that has additional insulationcompared to standard BNC and MHV connectors that makes it saferfor handling HV by preventing accidental contact with thelive wire connector in an unmated connector or plug.
silicon photomultiplier
A solid-state avalanche photodiode sensitive to single photoelectron signals.
shallow inelastic scattering.
surface installation team
An organizational unit responsible for logistics and integration in South Dakota.
Experiment sited in the Kamioka-mine, Hida-city, Gifu, Japan that uses a large water Cherenkov detector to study neutrino properties through the observation of solar neutrinos, atmospheric neutrinos and man-made neutrinos.
Square Kilometer Array
International radio telescope array planned to start data-taking in 2027.
SLAC National Accelerator Laboratory
US national laboratory in Menlo Park, CA.
spill location system
A system residing at the DUNE far detector site that provides information, possibly predictive, indicating periods of time when neutrinos are being produced by the Fermilab Main Injector beam spills.
standard model
Refers to a theory describing the interaction of elementary particles.
SubMiniature version A
Connector interface for coaxial cableswith a screw-type coupling mechanism.
standard-model extension
an effective field theory that contains the SM, general relativity, and all possible operators that break Lorentz symmetry (Wikipedia).
Event that occurs upon the death of certain types of stars.
supernova neutrino burst
A prompt increase in the flux of low-energy neutrinos emitted in the first few seconds of a core-collapse supernova. It can also refer to a trigger command type that may be due to this phenomenon, or detector conditions that mimic its interaction signature.
supernova neutrino burst and low energy
Supernova neutrino burst and low-energy physics program.
signal to noise and distortion ratio
Also known as SINAD. Ratio of the RMS signal amplitude to the mean value of the root-sum-square of all other spectral components, including harmonics, but excluding DC levels. It is a good indication of the overall dynamic performance of an ADC because it includes all components which make up noise and distortion.
SuperNova Early Warning System
A global supernova neutrino burst trigger formed by a coincidence of SNB triggers collected from participating experiments.
Sudbury Neutrino Observatory
The Sudbury Neutrino Observatory was a detector built 6800 feet under ground, in INCO’s Creighton mine near Sudbury, Ontario, Canada. SNO was a heavy-water Cherenkov detector designed to detect neutrinos produced by fusion reactions in the sun.
SuperNovaObservatories with GLoBES
From the official description: SNOwGLoBES is public software for computing interaction rates and distributions of observed quantities for SNB neutrinos in common detector materials.
signal-to-noise ratio.
Distinguishes one of the DUNE far detector technologies by the fact that it operates using argon in its liquid phase only.
single photoelectron
A single photoelectron.
Serial Peripheral Interface
The Serial Peripheral Interface is asynchronous serial communication interface specification used for short distancecommunication, primarily in embedded systems.
SPICE("Simulation Program with Integrated Circuit Emphasis") is a general-purpose,open-source analog electronic circuit simulator. It is a program used in integratedcircuit and board-level design to check the integrity of circuit designs and topredict circuit behavior.
SP module
single-phase DUNE FD module.
short-range correlated nucleon-nucleon interactions.
The Superconducting Super Collider was to be a huge underground ring complex beneath the area near Waxahachie, Texas, USA, that would have been the world’s most energetic particle accelerator. It was begun in 1990, but canceled by the U.S. Congress in 1993 (scientificamerican.com Oct 2013).
solid-state disk
Any storage device that may provide sufficient write throughput to receive, both collectively and distributed, the sustained full rate of data from a far detector module for many seconds.
single sign-on
Often used to indicate that a group of services, such as DocDB or the DUNE Wiki share common sign-in credentials and active sessions. Fermilab services that say "Sign in with SSO username and password" mean to use your Services username and password.
SiPM signal processor.
straw tube tracker.
Single Transverse Variables
Kinematical variables obtained by projecting the neutrino interaction onto the transverse plane.
Sanford Underground Research Facility
The laboratory in South Dakota where the LBNF FSCF will be constructed and the DUNE FD will be installed and operated.
Theoretical symmetry between a fermion and a boson.
Software & Computing.


T2K (Tokai to Kamioka) is a long-baseline neutrino experiment in Japan studying neutrino oscillations.
A cylindrical cryostat at Fermilab primarily used for developing scintillation light collection technologies for LArTPC detectors.
trip action plan
A document required for any trip by a worker to the underground area at SURF, per that site’s access control program; it describes the work to be accomplished during the trip.
technical board
The DUNE organization responsible for evaluating technical decisions.
technical coordination
The DUNE organization responsible for overall integrationof the detector elements and successful execution of the detectorconstruction project; areas of responsibility includegeneral project oversight, systems engineering, QA and safety.
trigger command message
A message flowing down the trigger hierarchy from global to local context. Also see TPM.
temporary construction opening
An opening in the side of a cryostat through which detector elements are brought into the cryostat; utilized during construction and installation.
technical coordinator
A member of the DUNE management team responsible for organizing the technical aspects of the project effort; is head of technical coordination.
technical design report
A formal project document that describes the experiment at a technical level.
total harmonic distortion
Total harmonic distortion is the ratio of the RMS value of the fundamental signal to the mean value of the root-sum-square of its harmonics.
temporary muon spectrometer
A muon spectrometer for the Near Detector that will be installed for the initial running period of DUNE, before the MPD detector component is ready.
time of flight
The time a particle takes to fly between two visible interactions observed in the detector. If combined with the distance traveled by the particle, for example a neutron, it can be used for energy reconstruction.
top FC
top field cage
The horizontal portions of the SP FC on the top of the TPC.
interim design report
An intermediatemilestone on the path to a full TDR.
tetra-phenyl butadiene
A WLS material.
time projection chamber
A type of particle detector that uses an E field together with a sensitive volume of gas or liquid, e.g., LAr, to perform a 3D reconstruction of a particle trajectory or interaction. The activity is recorded by digitizing the waveforms of current induced on the anode as the distribution of ionization charge passes by or is collected on the electrode (TPC is also used for "total project cost").
trigger primitive message
A message flowing up the trigger hierarchy from local to global context. Also see TCM.
trigger candidate
Summary information derived from the full data stream and representing a contribution toward forming a trigger decision.
trigger command
Information derived from one or more trigger candidates that directs elements of the far detector module to read out a portion of the data stream.
trigger decision
The process by which trigger candidates are converted into trigger commands.
trigger notification
Information provided by MTL to ETL about trigger decision processing.
trigger primitive
Information derived by the DAQ FE hardware that describes a region of space (e.g., one or several neighboring channels) and time (e.g., a contiguous set of ADC sample ticks) associated with some activity.
Taiwan Semiconductor Manufacturing Company.
transient voltage suppression.


UA1 (Underground Area 1) was a particle detector at CERN’s Super Proton Synchrotron (SPS). It ran from 1981 until 1990, when the SPS was used as a proton-antiproton collider, searching for traces of W and Z particles in collisions. (CERN) The UA1 dipole magnet was reused in the NOMAD experiment and currently provides the magnetic field for the T2K ND280 detector.
Universal Asynchrous Receiver/Transmitter
A universalasynchronous receiver-transmitter is a computer hardware device for asynchronousserial communication in which the data format and transmission speeds are configurable.
user datagram protocol
A simple, connectionless Internet protocol that supports data integrity checksums, requires no handshaking, and does not guarantee packet delivery.
concrete encased electrode
U.S. National Electrical Code grounding method refered to as Concrete Encased Electrode.
ultra-high molecular weight polyethylene.
ultra high vacuum.
underground installation team
An organizational unit responsible for installation in the underground area at the SURF site.
University of Campinas, Sao Paulo, Brazil.
UNIX product distribution
A tool for uploading and downloading pre-built software products between local systems and centralized software distribution servers. UPD is not frequently used on DUNE because newer tools are more convenient.
UNIX product support
A software tool that sets up a consistent environment of versions of pre-installed products and their dependencies on UNIX-like platforms.
Micro Telecommunications Computing Architecture
The computer architecture specification followed by the crates that house charge and light readout electronics in the DP module.
universal verification methodology
The Universal Verification Methodology is a standardized methodology for verifying integrated circuit designs.


A neutrino oscillation fitting framework that is used by T2K; the name stands for VALencia-Oxford-Rutherford, the original three institutions that developed it.
virtual organization
A database containing a list of member names, certificate distinguishing information, and a list of permissions members have to access computing grid and data resources.
vacuum ultra-violet.


WA105 DP demonstrator
The 3x1x1 m WA105 DP prototype detector at CERN.
work breakdown structure
An organizational project management tool by which the tasks to be performed are partitioned in a hierarchical manner.
Wire-Cell Toolkit
A software toolkit with data flow processing components for LArTPC noise and signal simulation, noise filtering, signal processing, and tomographic 3D ionization activity imaging.
working group
A group of persons working together to achieve specified goals.
warm interface board
Digital electronics situated just outside the SP cryostat that receives digital data from the FEMBs over cold copper connections and sends it to the RCE FE readout hardware.
warm interface electronics crate
Crates mounted on the signal flanges that contain the WIBs.
weakly-interacting massive particle
A hypothesized particle that may be a component of dark matter.
A vertical excavation at SURF connecting two drifts, not connecting to the surface.
wire board
At the head end of the APA in the SP TPC, stacks of electronics boards referred to as "wire boards" are arrayed to anchor the wires. They also provide the connection between the wires and the cold electronics.
A tomographic automated 3D neutrino event reconstruction method for LArTPCs.
Worldwide LHC Computing Grid
Worldwide LHCComputing Grid.
A material or process by which incident photons are absorbed by a material and photons are emitted at a different, typically longer, wavelength.
warehouse management system
Commercial software package used to track shipments and interface to freight forwarders. This includes a database for shipping.
White Rabbit
A component of the timing system that forwards clock signal and time-of-day reference data to the master timing unit.
WR grandmaster
White Rabbit grandmaster.
White Rabbit μTCA Carrier Hub
A card mounted in μTCA crate that recieves time syncronization information and trigger data packets over WR network and disributes them to the AMC over μTCA backplane.
White Rabbit TimeStamping Node
A unit on the WR network that timestamps the trigger signals and sends out trigger data packets to WR-MCH.


Extended ARAPUCA design with WLS coating on only the external face of the dichroic filter window(s) but with a WLS doped plate inside the cell.
extensible markup language
A markup language that defines a set of rules for encoding documents in a format that is both human-readable and machine-readable.



Used to delete some portion of a data stream that does not significantly deviate from zero or intrinsic noise levels. It may be applied at different granularity from per-channel to per detector unit.


two particle, two hole.
35 ton prototype
A prototype cryostat and SP detector built at Fermilab before the ProtoDUNE detectors.
3D scintillator tracker
The core part of the 3D projection scintillator tracker spectrometer in the near detector conceptual design.
3D scintillator tracker spectrometer
The 3D projection scintillator tracker spectrometer in the near detector conceptual design.
The depth in feet (1480 m) of the top of the cryostats underground at SURF; used more generally to refer to the DUNE underground area. Called the "4850 level" or "4850L".