Neutrinos

Part of Experimental Particle Physics

The neutrino group at Pittsburgh includes Dytman, Naples, and Paolone. Paolone started the neutrino effort here at Pittsburgh as co-spokesman of DONUT (FNAL 872) in which he received support through the DOE OJI program and observed the charged current interaction of the nt for the first time. After Naples came to the department, both Paolone and Naples (also a recipient of an OJI while still at KSU) joined the MINOS collaboration which has begun its data collecting phase. Naples’ work on the neutrino program began with NuTeV. She has worked on this project since it was in the proposal stage. Her main contribution to NuTeV was the design, construction, and operation of the precision calibration and spectrometer, crucial to improving electroweak and QCD measurements in NuTeV. Recently Naples and Paolone have joined the MINERA collaboration which will place a fine-grained neutrino detector in the NUMI beamline. The results of MINERA will reduce the systematic errors on fundamental neutrino parameters, such as Dm2.

MINOS is a neutrino oscillation experiment that will make precision measurements of both the mass differences between two of the neutrino mass eigenstates and the level of mixing of these eigenstates in the muon and tau neutrinos. This study will be done using the Fermilab Main Injector (MI) accelerator, which will produce an almost pure muon neutrino beam of mean energy of a few GeV. The properties of the beam will be measured using a detector on the Fermilab site called the "Near Detector/ND". A similar but much larger detector will be located at the Soudan mine in Minnesota, 730 km away ("Far Detector/FD"). The differences in the beam properties between the ND and FD will allow us to extract the neutrino mass eigenstate properties. On MINOS Naples designed the Pad Ionization Chamber (PIC) detectors as the basic element for the muon and hadron beam monitoring systems in MINOS. This was important to the smooth and successful commissioning phase of the NUMI beam. MINOS data-taking is now underway. The Pittsburgh group will be continuing its role in the Near Detector deep inelastic scattering cross section measurement and hopes to have a preliminary result by late summer. This result will be important in validation of the Near Detector spectrum and to tune cross section models for the oscillation measurement. Hadron rescattering is an important part of the neutrino nucleus event generator. Dytman is rewriting the relevant code to better reflect the large body of existing data and provide a clean way to determine the systematic error contribution to oscillation parameters.

Upcoming neutrino oscillation experiments in the United States (such as MINOS and NOA), Europe and Japan are driving the construction of new, very intense neutrino beam-lines required to achieve reasonable event rates at detectors located hundreds of kilometers away. These new beam-lines will allow one to initiate a vigorous research program at a detector, located close to the production target, where event rates are much higher than at the previous generation of neutrino beam facilities. In addition, it is neutrino oscillation experiments, with their low-energy neutrinos and massive nuclear targets, which highlight the need for much improved knowledge of low-energy neutrino–Nucleus interactions. At Fermilab, the new neutrino facility NuMI designed for MINOS is based on the MI accelerator. The neutrino beams from the MI yield several orders of magnitude more events per kg of detector per year of exposure than has ever been achieved before. To take advantage of these major improvements in experimental neutrino physics possible with the NuMI beam and facility, a collaboration of elementary particle and nuclear physics groups and institutions named "MINERA" (Main INjector ExpeRiment: A) has been formed, with the University of Pittsburgh group being one of the founding members and having responsibility for the readout electronics. The Minera experiment, a precision neutrino scattering experiment in the energy regime of interest for current and future neutrino oscillation experiments, has been approved and is in the final design stages. Our group contributed to understanding the physics sensitivity of the experiment and to the detector optimization studies. The Pitt group is responsible for the front-end electronics system, HV bases and light injection system. Naples, Paolone, and Fermilab colleague Rubinov are completing the design and testing of prototype front-end boards and HV bases. Dytman, along with colleages at Tufts University, will design and build the light injection system.
See Links:
• https://www-numi.fnal.gov/
• http://minerva.fnal.gov/
• http://www-minos.phyast.pitt.edu/