1 / 41

neutrino mass

neutrino mass. a long wait for a little weight. Stuart Freedman memorial symposium Berkeley, Jan 11, 2014. Hamish Robertson, University of Washington. Neutrinos oscillate, have mass. SNO. KamLAND. Super- Kamiokande. What is the neutrino mass scale?.

ziven
Download Presentation

neutrino mass

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. neutrino mass a long wait for a little weight Stuart Freedman memorial symposium Berkeley, Jan 11, 2014 Hamish Robertson, University of Washington

  2. Neutrinos oscillate, have mass SNO KamLAND Super-Kamiokande

  3. What is the neutrino mass scale? Particle Physics Cosmology

  4. Neutrino mass from Beta Spectra With flavor mixing: mixing neutrino masses from oscillations mass scale

  5. Mass limits from tritium

  6. Hamish Robertson, Stuart Freedman, Tom Bowles, Carol Bowles, Karl-Erik Bergkvist. Erice 1980. (from Tom)

  7. Tom Bowles, Carol Bowles, Stuart Freedman, Hamish Robertson, Erice 1980. (from Tom)

  8. Magnetic spectrometers showed no kink. But they had shape correction factors. "Contrary to intuition, a null result is not inherently more reliable than a positive one.” J.J. Simpson Grabowski spectrometer

  9. Current status: Mainz: solid T2, MAC-E filter C. Kraus et al., Eur. Phys. J. C40, 447 (2005) Troitsk: gaseous T2, MAC-E filter V. Aseev et al., PRD 84 (2011) 112003 Together:… mv < 1.8 eV (95% CL)

  10. Mass and mixing parameters Oscillation Kinematic Marginalized 1-D 1- uncertainties. *C. Kraus et al., Eur. Phys. J. C40, 447 (2005); V. Aseev et al. PRD 84 (2011) 112003. Other refs, see Fogli et al. 1205.5254

  11. AtKarlsruhe Institute of Technology uniquefacilityforclosed T2cycle: Tritium Laboratory Karlsruhe KATRIN A direct, model-independent, kinematic method, based on β decay of tritium. TLK ~ 75 m longwith 40 s.c. solenoids

  12. First measurement, UIE = 700V, electron gun source. July 12, 2013. ~0.4 eV

  13. Measuring something and getting it wrong?

  14. A window to work in Molecular excitations Energy loss

  15. KATRIN’s uncertainty budget σ(mv2) 0 0.01 eV2 Statistical Final-state spectrum T- ions in T2 gas Unfolding energy loss Column density Background slope HV variation Potential variation in source B-field variation in source Elastic scattering in T2 gas σ(mv2)total= 0.025 eV2 mv< 0.2 eV(90 % CL)

  16. What is the branching ratio for T2 → 3HeT+? Need a test of the final-state theory for KATRIN and Project 8 Tritium Recoil-Ion Mass Spectrometer (TRIMS)

  17. starting 2016 KATRIN Present Lab Limit 1.8 eV Mass Range Accessible

  18. K. Abazajian, CF5 Summary

  19. LEPTONS QUARKS TeV t b τ c GeV μ s d MeV u e keV eV νh νm νl meV ??

  20. starting 2016 KATRIN Present Lab Limit 1.8 eV Mass Range Accessible

  21. The Last Order of Magnitude If the mass is below 0.2 eV, how can we measure it? KATRIN may be the largest such experiment possible. σ(mv)2 ~ 0.38 eV2 Size of experiment now: Diameter 10 m. Source T2 column density near max Rovibrational states of THe+, HHe+ molecule Next diameter: 300 m!

  22. Cyclotron radiation from tritium beta decay (B. Monreal and J. Formaggio, PRD 80:051301, 2009) Radiated power ~ 1 fW 25.5-GHz waveguide cell Working on the UW prototype

  23. Signal is a rising “chirp” in frequency

  24. Project 8: a phased approach

  25. Project 8 sensitivity

  26. Neutrino Mass Limits from Beta decay

  27. Neutrino mass: some milestones Construction Running 2013 2014 2015 2016 2017 2018 2019 KATRIN: Project 8: Proof concept Prototype Phase I Planck: Analysis 2

  28. Stuart Freedman, Steve Elliott, Hamish Robertson. Spanish coast 1992. Photo by John Wilkerson.

  29. Capture of relic Neutrinos PTOLEMY project

  30. Capture of relic Neutrinos PTOLEMY project

  31. PTOLEMY Experimental Layout Low Field Region Cryogenic Calorimeter (~0.1eV) Tritium Source Disk (Surface Deposition) Long High Uniformity Solenoid (~2T) ~50-150eV below Endpoint High Field Solenoid 0-1keV (~150eV) E0+30kV E0-18.4keV E0 RF Tracking (38-46 GHz) e- Time-of-Flight (De-accelerating Potential) MAC-E filter (De-accelerating Potential) Accelerating Potential Accelerating Potential

  32. PTOlemy summary • 100 g of tritium (1 MCi) on 12-m diameter disk. • Relic capture rate ~ 10/year without local clustering. • Also presumably able to measure mass, active and sterile. • Transition-edge sensor array to provide basic 0.1-eV resolution. • Tagging with RF cyclotron radiation a la Project 8. • Necessary to understand quantum effects of binding of T2 on surface.

  33. Inputs • Present laboratory limit 1.8 eV (90% CL) from Mainz and Troitsk experiments on tritium • KATRIN experiment under construction. • Project 8 in proof-of-concept phase. • Cosmological inputs driven by Planck, SPT, ACT, Sloan …

  34. First Planck analysis (March 2013) Planck XVI WP = WMAP Polarization data AL = weak lensing parameter τ = optical depth at recombination “…Planck lensing likelihood favours largerΣm than the temperature power spectrum.”

  35. Cyclotron radiation from tritium beta decay (B. Monreal and J. Formaggio, PRD 80:051301, 2009) 25.5-GHz waveguide cell

  36. Neutrinoless Double Beta Decay Depends on mv but not a `direct’ measurement 1 sigma W. Rodejohann, 1206.2560

  37. Electron Capture Holmium Expt (ECHO) 187 J.F. Wilkerson

  38. Electron Capture Holmium Expt (ECHO) 187 J.F. Wilkerson

  39. Neutrino mass Physics Impact

  40. summary • Direct mass measurements are largely model independent: • Majorana or Dirac • No nuclear matrix elements • No complex phases • No cosmological degrees of freedom • One experiment in construction (KATRIN); 2015 start. • Three experiments in R&D (Project 8, ECHo, PTOLEMY)

More Related