Fermilab Accelerator Complex

Fermilab’s accelerator complex accelerates protons to high energies before sending them out to various experiments.

Fermilab Accelerator Complex consists of four accelerators that work together to provide world-class particle beams for experiments at the Intensity Frontier.
Batavia, Illinois Location
2012 Start of Operations
2,095 (FY 2022) Number of Users


Booster Neutrino Beam: The Booster accelerator is a ring 1,500 feet in circumference that receives 400 MeV protons from the linac and accelerates them to 8 GeV. These protons are used to generate secondary particle beams to serve the experimental program. The Booster Neutrino Beam is produced to serve several operating and planned Short-Baseline Neutrino (SBN) oscillation experiments.

Muon Campus: A portion of the proton beams are extracted to create muon beamlines serving the Fermilab Muon Campus beginning in 2016 where the presently-running Muon g-2 experiment is situated and the Muon-to-electron Conversion (Mu2e) experiment is under development.

Neutrinos at the Main Injector (NuMI): The Main Injector takes the 8 GeV energy protons from the Booster and accelerates them to 120 GeV. These highly energetic protons strike a carbon target to generate muons that subsequently decay to muon neutrinos, resulting in the most intense neutrino beam in the world. The muon neutrino beam is used for studies of both the disappearance of muon neutrinos and the appearance of electron and tau neutrinos. Two experiments currently gather data from the NuMI beam line, a third is starting operations, and a fourth is planned.


  • MicroBooNE:The MicroBooNE short-baseline neutrino experiment is the largest Liquid Argon Time Projection Chamber (LArTPC) neutrino detector built in the U.S. The 170 ton experiment began operations in 2015 and measures low energy neutrino cross sections and investigate the unexpected excess events observed by the MiniBooNE experiment. The detector serves as the necessary next step in a phased program towards the construction of massive, kiloton scale LArTPC detectors, the preferred technology for the future Deep Underground Neutrino Experiment (DUNE).
  • ICARUS: The ICARUS collaboration is investigating signs of physics that may point to a new kind of neutrino called the sterile neutrino. Other experiments have made measurements that suggest a departure from the standard three-neutrino model. ICARUS is also to be investigating the various probabilities of a neutrino interacting with different types of matter as well as neutrino-related astrophysics topics.
  • SBND: The Short-Baseline Near Detector (SBND) will be one of three liquid argon neutrino detectors sitting in the Booster Neutrino Beam (BNB) at Fermilab as part of the Short-Baseline Neutrino Program. MicroBooNE and the ICARUS-T600 are the intermediate and far detectors in the program, respectively. SBND is a 112 ton active volume liquid argon time projection chamber (LArTPC) located only 110 m from the BNB neutrino source. The detector is currently in the construction phase and is anticipated to begin operation shortly. SBND will record over a million neutrino interactions per year. By providing such a high statistics measurement of the un-oscillated content of the booster neutrino beam, SBND is a critical element in performing searches for neutrino oscillations at the Fermilab Short-Baseline Program.
  • Muon g-2: The Standard Model of Particle Physics makes detailed predictions about the gyromagnetic ratio associated with the precession of muon particles in the presence of a strong magnetic field. The Muon g-2 experiment was designed to achieve world-record precision in measuring these behavior of muons (one part In a billion). The experiment is a great test of the Standard Model and any deviation from the predictions will constitute a major discovery. After starting data collection in 2018, the experiment released its first results in spring 2021.
  • Mu2e:Mu2e will directly probe the Intensity Frontier as well as aid research on the Energy and Cosmic frontiers with precision measurements required to characterize the properties and interactions of new particles discovered at the Intensity Frontier. Observing muon-to-electron conversion will remove a hurdle to understanding why particles in the same category, or family, decay from heavy to lighter, more stable mass states. Physicists have searched for this since the 1940s. Discovering this is central to understanding what physics lies beyond the Standard Model. The experiment is presently under design, construction, and testing.
  • MINERvA:This is a neutrino scattering experiment that seeks to measure low energy neutrino interactions both in support of neutrino oscillation experiments and also to study the strong dynamics of the nucleon and nucleus that affect these interactions.
  • NOvA: The NOvA far detector, which was completed at Ash River, Minnesota during October, 2014, will use the NuMI beam to directly observe and measure the transformation of muon neutrinos into electron neutrinos with great precision. NOvA will also make important indirect measurements of the mass ordering of the three known neutrino types, which will be a key piece of information in determining the currently unknown masses of neutrinos.
  • DUNE:The Deep Underground Neutrino Experiment (DUNE) is a leading-edge, international experiment for neutrino science and proton decay studies. DUNE will consist of two neutrino detectors placed in the world’s most intense neutrino beam. One detector will record particle interactions near the source of the beam, at Fermilab in Illinois. A second, much larger, detector will be installed more than a kilometer underground at the Sanford Underground Research Laboratory in Lead, South Dakota — 1,300 kilometers downstream of the source. DUNE has three scientific thrusts: exploring whether and how neutrinos might be the reason the universe is made of matter; illuminating neutron star and black hole formation by using neutrinos to look into the cosmos; and moving closer to realizing Einstein's dream of a unified theory of matter and energy by searching for proton decay.