Upgraded conventional neutrino beams: Neutrino superbeams

The capabilities of greatly upgraded conventional neutrino beams and the comparison with neutrino factories is under study. This page collects together some useful working information-- and at the bottom you can find links to studies that have already been done!
  • GROUP REPORT: Oscillation Measurements with Upgraded Conventional Neutrino Beams
    V. Barger et al., hep-ex/0103052 (FERMILAB-FN-703), Addendum to Report FN-692 to the Fermilab Directorate, March 5, 2001.
  • MI upgrade limitations Conf-97-199, W. Chou

  • NUMI low energy beam with L = 732 km uoscillation signals for point IA1 (LMA scenario) but with sin**2 2theta(13) = 0.01, from Steve Geer.

  • NUMI medium energy beam with L = 2800 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.04, from Steve Geer.
  • NUMI medium energy beam with L = 2800 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.01, from Steve Geer.
  • NUMI medium energy beam with L = 2800 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.001, from Steve Geer.
  • NUMI medium energy beam with L = 2800 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.001, and negative delta m**2, from Steve Geer.

  • NUMI medium energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.04, from Steve Geer.
  • NUMI medium energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.01, from Steve Geer.
  • NUMI medium energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.001, from Steve Geer.
  • NUMI medium energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.001, negative dm**2, from Steve Geer.

  • NUMI high energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.01, from Steve Geer.
  • NUMI high energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.001, from Steve Geer.
  • NUMI high energy beam with L = 7300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.001, and negative dm**2, from Steve Geer.

  • NUMI high energy beam with L = 9300 km oscillation signals for point IA1 (LMA scenario) with sin**2 2theta(13) = 0.01, from Steve Geer.

  • Event Energy Spectra for L = 2800,7300 km and different angles This file shows the charged current event energy spectra for different components of the NUMI Medium Energy beam AND the neutral current energy spectra, and on the last page compares the NC visible energy spectra with the nu_mu to nu_e and nu_e to nu_e charged current energy spectra. These plots were made with the group 4 background ntuples and Steve Geer's flux histograms shown in the other links from this page. Finally, the energies shown are for a perfect detector, perfect acceptance, and NO neutral current rejection factor. Also, because of limitations in the background ntuples and the signal histograms, respectively, these plots have NO ENTRIES in them from neutrinos with energies below 1GeV, or above 20GeV, but the latter will be remedied soon. This is simply meant to be a first pass look at what the neutral currents look like. From Debbie Harris.

  • Event Energy Spectra for L =7300 km , MINOS High energy beam neutrino running
  • Event Energy Spectra for L =7300 km , MINOS High energy beam antineutrino running
    WAY PRELIMINARY: These two files compare 3 different scenarios: sin^22theta_13 = .001 with two different signs for delta m^2, and sin^2theta_13=.01 with one sign of delta m^2. There is an assumed hadron energy resolution of 15%/sqrt(e_had) and electron energy resolution of 5%/sqrt(e_electron), which I think is near what a liquid argon calorimeter would achieve. The effect of such a good energy resolution is tiny, and switching the sign of delta m^2 is a huge effect. Basically for one sign of delta m^2 the signal is much much smaller than the nu-e contamination, and for the other sign of delta m^2 the signal is about the same size, but with a different energy spectrum. For sin^22theta_13=.01, the signal is at least much bigger than the intrinsic nue background, and you just have to worry about getting rid of the nc background. For these plots there are no neutrinos below 1GeV or above 50GeV, but this effect is probably very small. Also, in nubar running the nu_e contamination is about 50% as large as the nubar_e contamination and so it should also be included...(and will be soon). From Debbie Harris starting with Steve Geer's flux files shown above.
  • 7/19/2000 Background Plots: Include intrinsic nu_e and tau->e backgrounds at sin^22theta_13=.01 for Low Medium and High Energy beams, at 732,2800, and 7300km. These plots show backgrounds from tau decays to electrons in charged current events. The assumptions made on cross section ratios and tau to electron energy spectra are shown on the first page, and comparisons on the later pages. From Debbie Harris starting with Steve Geer's flux files shown above.

  • Comparison of neutrino vs antineutrino running for Horn Beam WAY PRELIMINARY: This file shows the cross-section weighted fluxes (at 732km) for two possible conventional beam: the solid lines are the minos high energy beam with the polarity of the horns set to focus positive pions making neutrino beams, and the dashed lines are the same thing but with the opposite polarity in the horns, to make a nubar beam. Note that there are about 34% as many nubar events as nu events: so the beamline is only 68% as efficient at creating and focusing negative pions vs positive pions. The nue/nubare event rate is about 50% in nubar running, compared to a <10% rate of nubare/nue in neutrino running. From Debbie Harris and the GEANT-based NUMI beam monte carlo.

  • Event rates table NUMI beam x 4 with L = 3000 km and 7200 km, from Heidi Schellman.

  • Ray Stefanski's talk from July 5, 2000 meeting This document describes some of the low energy neutrino physics that is of interest, as well as the salient features of the PRISM project in Japan.

    References about Superbeams:

    CP and T violation in long baseline experiments with low energy neutrino by Joe Sato, hep-ph/0006127 , June 13, 2000.
    A Comparison of the Physics Potential of Future Long Baseline Neutrino Oscillation Experiments by K. Dick, M. Freund, P.Huber, M. Lindner, hep-ph/0008016 ,August 2, 2000.
    Masses and Mixings from Neutrino Beams pointing to Neutrino Telescopes by K. Dick, M. Freund, P.Huber, M. Lindner hep-ph/0006090 , June 9, 2000.
    Neutrino Experiments at the Japan Hadron Facility You can find at this website slides from talks given about the facility, as well as the letter of intent--which describes the sensitivities for both wide and narrow band conventional neutrino beams with average energies ranging from 1 to 3 GeV (aimed at the SuperKamiokande detector).
    2nd International Workshop on Neutrino Beams and Instrumentation This is the welcoming web page for a workshop that took place at Fermilab on September 6-9, 2000. There will eventually be a link to the scanned in transparencies that were shown at this workshop-- including things like cost estimates for the CNGS beamline, as well as how far the "diggable" rock extends under CERN. Also there was a good talk given here about the JHF neutrino beam--both talks mentioned here were in the overview session.


    Last updated July 6, 2000
    Suggestions ? Contact sgeer@fnal.gov