Thursday, October 26, 2023

The Fermi Research Alliance has awarded Prof. Yasar Onel a $91,257 grant to design a helium gas closed-loop regulation system for the Neutrinos at the Main Injector (NuMI) beam monitors at Fermilab in Illinois. The NuMI project creates an intense beam of neutrinos aimed toward the NOvA Far Detector facility near Ash River, Minn.

NuMI has four beam monitors which check the neutrino beam quality. They utilize high-purity gaseous helium as an ionization media for their ionization chambers. The current operations of these monitors consume helium gas from a helium bottle farm and vent the spent helium gas to the atmosphere. Because the cost of helium gas becomes expensive, Onel's team proposes to make a helium gas closed-loop regulation system. 

As part of the project with the Fermi Accelerator Physics division, Onel and his team will work on a gas regulation design study, construction of a prototype closed loop system, a gas regulator final design study, and consultation on a gas regulator system for the DUNE NuMI beam monitors.

DUNE Experiment

The new U.S. flagship of the HEP is the DUNE experiment. The Fermilab accelerators send a beam of neutrinos underground about 800 miles to a Far Detector (an old mine in South Dakota) and the Near Detector will be at Fermilab. This new beam is a Horn-focused wide-band beam that builds on the success of NuMI.

• broad spectrum of neutrinos (and anti- neutrinos) is peaked at 2.5 GeV

• focusing parameters optimized to maximize sensitivity to CPV (Charge-Particle Violation)

• 1.2 MW, upgradeable to 2.4 MW

DUNE’s physics goals are:

• determine the neutrino mass ordering, observe, and measure CP violation in the (if it

is present) in the neutrino sector over the entire possible parameter space.

• serve as a large underground neutrino observatory with sensitivity to neutrinos from

astrophysical sources (solar, atmospheric, supernova burst) and BSM physics.

Neutrino production

The first step in the production of the NuMI beam is to direct a beam of protons from Fermilab's Main Injector onto a carbon target. Interactions of the proton beam in the target produce mesons, primarily pions and kaons, which are focused on the beam axis by two magnetic horns. The mesons then decay into muons and neutrinos during their flight through a long decay tunnel. A hadron absorber downstream of the decay tunnel removes the remaining protons and mesons from the beam. The muons are absorbed by the subsequent earth shield, while the neutrinos continue through it to the near detectors on-site at Fermilab. The neutrinos then travel through the Earth to the far detector cavern far detector up to 800 miles away at South Dakota., then onwards into space.