The Deep Underground Neutrino Experiment (DUNE) is an international scientific collaboration that is building and operating a next-generation neutrino experiment in the United States. The experiment will study the properties of neutrinos, subatomic particles that are among the most abundant in the universe but are also among the least understood.

DUNE will be located in the Sanford Underground Research Facility (SURF) in Lead, South Dakota. SURF is a former gold mine that is now a world-class underground laboratory. The DUNE detectors will be placed in a large, excavated cavern that is over 4,800 feet (1,500 meters) underground. This depth will shield the detectors from cosmic rays, which are high-energy particles that can interfere with neutrino measurements.

The DUNE experiment will consist of two detectors:

A near detector, which will be located near the neutrino source at Fermilab in Illinois. The near detector will measure the properties of the neutrinos before they travel to the far detector.
A far detector, which will be located at SURF. The far detector will measure the properties of the neutrinos after they have traveled through the Earth.

The DUNE detectors will be filled with liquid argon. Liquid argon is a dense, transparent material that is ideal for detecting neutrinos. When a neutrino interacts with an argon atom, it will produce a small flash of light. The DUNE detectors will have thousands of photomultiplier tubes that will detect these flashes of light and record the energy and direction of the neutrinos.

DUNE will be the largest and most sensitive neutrino experiment ever built. The experiment will collect data for at least ten years, and it is expected to make major discoveries about the properties of neutrinos.

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Physics Goals of DUNE

The DUNE experiment has a broad range of physics goals, including:

Measuring the neutrino mass hierarchy. This is one of the most important unanswered questions in particle physics. The neutrino mass hierarchy refers to the ordering of the three neutrino masses.
Searching for neutrino oscillations. Neutrino oscillations are a phenomenon in which neutrinos change flavor as they travel. DUNE will search for new types of neutrino oscillations that could provide clues to the origin of matter and the antimatter asymmetry in the universe.
Studying the properties of supernova neutrinos. Supernovas are the explosions of massive stars. When a supernova explodes, it releases a burst of neutrinos. DUNE will study the properties of supernova neutrinos to learn more about the physics of supernovae.
Searching for dark matter. Dark matter is a mysterious substance that makes up about 85% of the matter in the universe. DUNE will search for dark matter particles by looking for interactions between dark matter and neutrinos.

DUNE Collaboration

The DUNE collaboration is a global collaboration of over 1,000 scientists from over 30 countries. The collaboration is led by the United States Department of Energy (DOE) and the National Science Foundation (NSF).

Construction and Timeline

The construction of the DUNE experiment began in 2021. The near detector is expected to be completed in 2029, and the far detector is expected to be completed in 2035. The DUNE experiment is expected to begin taking data in 2030.

Cost

The estimated cost of the DUNE experiment is $1.5 billion. The DOE and the NSF are providing the majority of the funding for the experiment.

Frequently Asked Questions (FAQ)

Q: What are neutrinos?

A: Neutrinos are subatomic particles that are among the most abundant in the universe. They are produced in nuclear reactions, such as those that occur in the sun and in nuclear power plants. Neutrinos are also produced in the atmosphere when cosmic rays interact with atoms.

References

Neutrino Physics at Fermilab

Fermilab is a leading center for neutrino physics research. Its facilities, including the Tevatron and NOvA experiments, have contributed significantly to the understanding of these enigmatic particles. The Tevatron, the world’s first superconducting accelerator, played a crucial role in the discovery of the top quark and the Higgs boson. NOvA, a long-baseline neutrino oscillation experiment, has provided valuable insights into neutrino mass hierarchy and mixing angles. In addition, Fermilab is involved in several other neutrino experiments, including DUNE, a next-generation neutrino oscillation experiment that is expected to shed light on the nature of dark energy and the role of neutrinos in the early universe.

Neutrino Detector Technologies

Neutrinos are elusive subatomic particles that are difficult to detect due to their extremely low interaction rate with matter. To study neutrinos, physicists have developed several detector technologies:

Water Cherenkov Detectors: Utilize large volumes of water to detect Cherenkov radiation produced by neutrinos interacting with the water. These detectors can identify the flavor of the neutrino and measure its energy and direction.
Scintillator Detectors: Contain large volumes of organic scintillating material that emit light when neutrinos interact with them. The intensity and pattern of the light emission provide information about the neutrino’s properties.
Liquid Argon Detectors: Utilize large volumes of liquid argon as the detection medium. These detectors have excellent spatial resolution and can provide detailed images of neutrino interactions.
IceCube Detector: A large-scale neutrino detector located at the South Pole. It utilizes the ice cap as the detection medium, detecting Cherenkov radiation produced by neutrinos interacting with the ice.
Kiloton Underground Xenon (LUX) Experiment: A dark matter detector that also has sensitivity to neutrinos. It uses a large volume of liquid xenon as the detection medium, which provides excellent discrimination between neutrinos and other particles.

Steel Neutrino Detector

A steel neutrino detector is a large-scale detector designed to detect and study neutrinos. It consists of a massive steel structure interspersed with layers of particle detectors. Neutrinos, which are subatomic particles with no electric charge and very little mass, interact with the steel nuclei via the weak force. This interaction produces a spray of secondary particles, which are detected by the detectors.

By studying the patterns of detected particles, scientists can infer the energy, direction, and flavor of the neutrinos. Steel neutrino detectors are particularly sensitive to high-energy neutrinos, which are produced in astrophysical processes such as supernova explosions and active galactic nuclei.

These detectors play a crucial role in neutrino physics research, contributing to our understanding of the properties of neutrinos, the sources of cosmic neutrinos, and the fundamental laws governing the universe.

Particle Physics Experiments Using Neutrinos

Neutrinos are fundamental particles that play a crucial role in particle physics and astrophysics. Particle physics experiments using neutrinos are designed to investigate their properties, interactions, and their role in the universe. These experiments utilize various techniques to study neutrinos, including direct detection, oscillation experiments, and astrophysical observations. By studying neutrinos, scientists aim to uncover fundamental insights into the Standard Model of physics, probe beyond-the-Standard-Model theories, and understand the nature of the universe.

Underground Neutrino Detectors

Underground neutrino detectors are large and complex experiments built deep underground to study neutrinos, which are subatomic particles with no electric charge and very little mass. These detectors are designed to shield the neutrinos from background radiation and other particles that could interfere with their detection.

Underground neutrino detectors are typically located deep in mines or underground tunnels, where the surrounding rock provides a barrier against cosmic rays and other radiation. The detectors are often filled with a large volume of liquid or plastic scintillator, which produces a flash of light when a neutrino interacts with it. The light is detected by photomultiplier tubes, which convert the light into electrical signals that can be analyzed.

Underground neutrino detectors have been used to study a wide range of neutrino properties, including their masses, their interactions with other particles, and their role in the evolution of the universe. These detectors have also been used to search for new particles and to study the physics of the early universe.

Fermilab Neutrino Research

Fermilab, located near Chicago, Illinois, is a primary center for neutrino research. Neutrinos are elementary particles that interact weakly with matter, making them difficult to study. Fermilab’s experiments focus on understanding neutrino properties, such as their mass and mixing angles.

One major experiment at Fermilab is NOvA (NuMI Off-Axis νe Appearance), which sends neutrinos from Fermilab’s accelerator to a detector 810 kilometers away in Minnesota. By comparing the number and properties of neutrinos arriving at the detector, NOvA has provided valuable insights into neutrino oscillations, which involve neutrinos changing between different types (electron, muon, and tau).

Fermilab is also involved in the DUNE (Deep Underground Neutrino Experiment), an international collaboration that will build a massive neutrino detector in South Dakota. DUNE aims to probe the parameters of neutrino oscillations with unprecedented precision, including the potential existence of a fourth neutrino type known as the sterile neutrino.

These experiments at Fermilab have significantly contributed to our understanding of neutrinos and their role in the universe. Ongoing research continues to explore the mysteries surrounding these enigmatic particles and their implications for fundamental physics.

Long-baseline Neutrino Experiments

Long-baseline neutrino experiments are large-scale scientific endeavors designed to study the properties of neutrinos and investigate fundamental questions in physics. They utilize intense beams of neutrinos produced at particle accelerators that are directed over long distances to underground detectors. These experiments play a crucial role in understanding neutrino oscillations, probing the nature of dark matter, and searching for new physics beyond the Standard Model.

High-Energy Neutrino Physics

High-energy neutrino physics investigates the properties and behavior of neutrinos at extremely high energies. Neutrinos are elementary subatomic particles that are nearly massless and lack electric charge. As a result, they interact with other matter very weakly, making them challenging to detect and study.

Neutrino Oscillations:

High-energy neutrino physics has led to the discovery of neutrino oscillations, where neutrinos can change their flavor (electron, muon, or tau) as they travel through space. This phenomenon has implications for neutrino masses and physics beyond the Standard Model of particle physics.

Cosmic Ray and Astrophysical Sources:

High-energy neutrinos can be produced by cosmic rays interacting with matter in the Earth’s atmosphere or in astrophysical objects such as active galactic nuclei, supernovae, and gamma-ray bursts. Detecting and analyzing cosmic neutrinos provides insights into these high-energy astrophysical processes.

Neutrino Telescopes:

To detect high-energy neutrinos, large underground or underwater detectors called neutrino telescopes are used. These telescopes use large volumes of material to capture neutrino interactions, resulting in signals that can be analyzed to determine the energy and flavor of the neutrinos.

Future Experiments:

Ongoing and planned high-energy neutrino physics experiments aim to explore the cosmic neutrino spectrum further, search for new physics beyond the Standard Model, and investigate the role of neutrinos in the evolution of the universe. These experiments include IceCube at the South Pole, Hyper-Kamiokande in Japan, and DUNE at Fermilab in the United States.

Neutrino Interactions in Matter

Neutrinos interact very weakly with matter, but they can undergo several types of interactions as they pass through it. These interactions include:

Elastic scattering: Neutrinos can scatter off electrons or nuclei without changing their energy.
Inelastic scattering: Neutrinos can scatter off electrons or nuclei and exchange energy with them.
Charged-current interactions: Neutrinos can interact with electrons or protons, producing a charged lepton (electron or muon) and a hadronic shower.
Neutral-current interactions: Neutrinos can interact with nuclei, producing a hadronic shower but not a charged lepton.

The probability of a neutrino interaction depends on its energy and the type of matter it is passing through. Neutrinos are more likely to interact with matter at higher energies and in denser materials.

Neutrino interactions in matter can be important for a variety of astrophysical processes, such as the formation of stars and the evolution of galaxies. They can also be used to probe the properties of matter in extreme environments, such as the interiors of stars and the core of the Earth.