MINOS+ was a continuation of the

MINOS Main injector neutrino oscillation search (MINOS) was a particle physics experiment designed to study the phenomena of neutrino oscillations, first discovered by a Super-Kamiokande (Super-K) experiment in 1998. Neutrinos produced by the NuMI ...

experiment (Main injector neutrino oscillation search) to measure

neutrino oscillation Neutrino oscillation is a quantum mechanics, quantum mechanical phenomenon in which a neutrino created with a specific lepton lepton number, family number ("lepton flavor": electron, muon, or tau lepton, tau) can later be Quantum measurement, mea ...

with improved electronics. It started taking data in 2013 and ran for 3 years. The experiment has ended and a 6-month dismantling project began in early October 2016.

Physics goals

*Measure sin²2''θ'' and Δ''m''² with higher precision. *Measure sin²2 and Δ² with higher precision. *Study high energy

neutrinos A neutrino ( ; denoted by the Greek letter ) is an elementary particle that interacts via the weak interaction and gravity. The neutrino is so named because it is electrically neutral and because its rest mass is so small ('' -ino'') that it ...

*Search for sterile neutrinos *Search for

tau neutrino The tau neutrino or tauon neutrino is an elementary particle which has the symbol and zero electric charge. Together with the tau (particle), tau (), it forms the third generation (physics), generation of leptons, hence the name tau neutrino. It ...

s *Non-standard interactions *Measurement of the neutrino time of flight *Search for

extra dimensions In physics, extra dimensions or extra-dimensional spaces are proposed as additional space or time dimensions beyond the (3 + 1) typical of observed spacetime — meaning 5-dimensional or higher. such as the first attempts based on the K ...

*Atmospheric neutrinos

Neutrino beam

MINOS+ uses the NuMI

beamline In accelerator physics, a beamline refers to the trajectory of the beam of particles, including the overall construction of the path segment (guide tubes, diagnostic devices) along a specific path of an accelerator facility. This part is either ...

generated at

Fermilab Fermi National Accelerator Laboratory (Fermilab), located in Batavia, Illinois, near Chicago, is a United States Department of Energy United States Department of Energy National Labs, national laboratory specializing in high-energy particle phys ...

. To produce the beamline, 120 GeV proton pulses from the Main Injector hit a water-cooled graphite target. The resulting interactions of protons with the target material produce

pion In particle physics, a pion (, ) or pi meson, denoted with the Greek alphabet, Greek letter pi (letter), pi (), is any of three subatomic particles: , , and . Each pion consists of a quark and an antiquark and is therefore a meson. Pions are the ...

s and

kaon In particle physics, a kaon, also called a K meson and denoted , is any of a group of four mesons distinguished by a quantum number called strangeness. In the quark model they are understood to be bound states of a strange quark (or antiquark ...

s, which are focused by a system of magnetic horns. These then travel down a long decay tunnel, and their decay produces a neutrino beam parallel to the meson beam. Most of these are

muon neutrino The muon neutrino is an elementary particle which has the symbol and zero electric charge. Together with the muon it forms the second generation of leptons, hence the name muon neutrino. It was discovered in 1962 by Leon Lederman, Melvin Schwa ...

s, with a small electron neutrino contamination. Neutrino interactions in the near detector are used to measure the initial neutrino flux and energy spectrum. Because they are weakly interacting and therefore usually pass through matter, the vast majority of the neutrinos travel through the near detector and the 734 km of rock, then through the far detector and off into space. For the initial 3-year run the NuMI beam will be in its medium energy configuration which will deliver the majority of neutrinos with an energy between 4 GeV and 10 GeV.

Relationship with NOνA

NOνA A nova ( novae or novas) is a transient astronomical event that causes the sudden appearance of a bright, apparently "new" star (hence the name "nova", Latin for "new") that slowly fades over weeks or months. All observed novae involve white ...

sits 14

milliradian A milliradian (International System of Units, SI-symbol mrad, sometimes also abbreviated mil) is an SI derived unit for angular measurement which is defined as a thousandth of a radian (0.001 radian). Milliradians are used in adjustment of ...

s off the central line of the NuMI beam. At this angle, there is an enhancement of neutrinos with an energy of 2 GeV, at which the ''L''/''E'' (baseline divided by energy) maximizes the oscillation of muon neutrinos. This causes a problem in that the signal you are looking for is a dip in a peak. MINOS+ sits on the central line of the beam so the full beam make up is seen, thus helping control systematic errors for the NuMI beam energy.

References

External links

MINOS+ experiment
record on

INSPIRE-HEP INSPIRE-HEP is an open access digital library for the field of high energy physics (HEP). It is the successor of the Stanford Physics Information Retrieval System (SPIRES) database, the main literature database for high energy physics since the 1 ...

{{Neutrino detectors Accelerator neutrino experiments Fermilab Particle experiments Neutrino experiments Fermilab experiments