1 / 18

Appearance in MINOS

Appearance in MINOS. University of Minnesota A.P. Schreckenberger DPF 2011. Introduction. A new MINOS analysis Complementary to appearance study First-time look at this oscillation mode by MINOS Currently under development – results in not too distant future Brief recap of apperance

kane
Download Presentation

Appearance in MINOS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. Appearance in MINOS University of Minnesota A.P. Schreckenberger DPF 2011

  2. Introduction • A new MINOS analysis • Complementary to appearance study • First-time look at this oscillation mode by MINOS • Currently under development – results in not too distant future • Brief recap of apperance • Motivation for analysis • Dataset & sensitivity estimates

  3. Appearance in MINOS • 8.2e20 protons-on-target analysis • 90% CL below the CHOOZ limit with normal hierarchy • Θ13 = 0 hypothesis disfavored at 89% CL • Less sensitive to inverted mass hierarchy

  4. Why • Greater sensitivity to inverted hierarchy • Δ • δ is CP-violating phase

  5. Why • A, Δ and α flip signs in hierarchy change • A and δ flip signs under charge conjugation Normal Hierarchy Inverted Hierarchy What happens to the three terms?

  6. Why • A, Δ and α flip signs in hierarchy change • A and δ flip signs under charge conjugation Normal Hierarchy Inverted Hierarchy

  7. Why • A, Δ and α flip signs in hierarchy change • A and δ flip signs under charge conjugation Normal Hierarchy Inverted Hierarchy

  8. Why • A, Δ and α flip signs in hierarchy change • A and δ flip signs under charge conjugation Normal Hierarchy Inverted Hierarchy

  9. Why • Appearance Probability as a function of energy • Generated using full probability expression

  10. Why • Is there new physics to be seen? • Are there matter effects specific to ? • Access to energies beyond the scope of reactor experiments • Experimental motivations • MiniBooNE & LSND • MINOS: and observations • Consistent at 2.0% CL withidentical oscillation parameterhypothesis

  11. How do we get • Horns focus off-axis particles of designated charge • Polarity determines which charge is focused Focusing Horns Target 2 m π− νμ νμ π+ 30 m 15 m 675 m

  12. How do we get • event rate suppressed due to decreased cross-section Neutrino Mode vs. Antineutrino Mode spectra νμ: 58.1% ͞νμ: 39.9% ͞νe+νe : 2.0% νμ: 91.7% ͞νμ: 7.0% ͞νe+νe : 1.3%

  13. Dataset Neutrinos ~ 8.2e20 POT Antineutrinos ~ 3.0e20 POT Special Run Periods

  14. RHC Sensitivity Estimate for LEM

  15. Combining & Analyses • Improve limits on θ13 with joint analysis • Similarly sized POT additions have constrained contours in the past • Pursue whether combined analysiswill facilitate more significantdisfavoring of the θ13 = 0 hypothesis

  16. Summary & Conclusion • Set limits on θ13 using an antineutrino beam • Estimated 3.5e20 POT exposure • Access to GeV energy scale neutrinos • Search for new physics • Anomalous matter effects • Antineutrino behavioral differences • Improve measurement of θ13 through a combined analysis

  17. Backup

  18. Appearance PIDs • Have used two particle identification algorithms (PIDs) in the past to select signal events • ANN11 – an artificial neural network • 11 input variables generate a PID output for analysis use • LEM – Library Event Matching • Matches topologies of candidate to library consisting of simulated background and signal events • Also produces a PID for analysis use • Offered increased sensitivity compared to ANN11

More Related