POFPA 17/3/06 A. Ceccucci K & B: Theory vs. Experiments LFV: further motivation to study rare kaon decays Report from my visit to Japan
K & B: Theory vs Experiment SM Observable Theoretical error Experimental error B(K0Lp0 n n) ~3% ?? B(K+p+ n n) ~6% ~75% AFB(B Xsl+l-) ~8% B(B Xsg) ~10% ~9% B(B Xsl+l-) ~13% ~20% AFB(B K(*)l+l-) ~15% ~30% B(B (K(*),r,w)g) ~25% ~40% B(Bs m+m-) < 2 x 10-7 B(B K*l+l-) ~35% Adapted from U. Haisch @ Flavour in the LHC era, 6-8 Feb 06, CERN
hep-ph/0511289
: Physics Motivation [1] Helicity suppressed decay [2] Decay Form of : left-handed (in SM) : spin 0 p0 copiously collected from K+ p+p0 [1] Helicity suppressed decay (A) Neutrino mass : implies . (B) Neutrino type : Majorana neutrino x2 larger branching ratio. [2] Decay Form of (B) Decay into different neutrino flavors : (A) Sensitive to any hypothetical weakly-interacting neutrals. [3] Cosmological Interests Neutron star cooling model through pion pole mechanism :
Branching Ratio New upper limit (E949) : 2/3 sample Saturation at 3.5x106 1/3 sample Conservative upper limit # signal < 113 (90%CL) subtracting the non-Kp2 bkgnds; New upper limit (E949) : A factor of 3 improvement from the previous best result.
Ceccucci visit to Japan CERN, March 16, 2006 Workshop poster Summary of Ceccucci visit to Japan CERN, March 16, 2006
“Mass Origin and Supersymmetry Physics” Grant in Aid for Scientific Research in Priority Areas Research period: April 2001 ～ March 2006 Purpose of this Research Program Pursue the answers to the following questions: Why does the matter have its mass ? What kind of physics law gives the mass of the matter ? 〇 Search for the Higgs particle, the mass origin. Proton Antiproton collision experiment at highest energy （ CDF experiment） 〇 Search for deviation from the Standard Model prediction, New Physics such as SUSY. Precise measurement with factory accelerators （ top, B, tau, K factories） 〇 Research and development for next-generation accelerator experiments. （ LHC, ILC，J-PARC，SuperB) 〇 Theoretical studies closely related to these experimental studies.
E391a Collaboration High Energy Accelerator Research Organization, KEK, Japan Joint Institute for Nuclear Research (Dubna), Russia Department of Physics, Kyoto University, Japan National Defense Academy of Japan, Japan Department of Physics, National Taiwan University, Taiwan Department of Physics, Osaka University, Japan Department of Physics, Pusan National University, Korea Research Center for Nuclear Physics, Osaka University, Japan Faculty of Science and Engineering, Saga University, Japan Department of Physics, University of Chicago, USA Department of Physics, Yamagata University, Japan
E391a method to detect KL ponn (along the beam axis)
E391a result at the KAON2005
Direct comparison Run-I and Run-II 5evts 1evts 0evts 4evts With the same data processing and cuts
Expected sensitivity Single Event Sensitivity G-N Limit KTeV Limit (Current Exp. Limit) Single Event Sensitivity G-N Limit 1-day 1-week Run-I Run-II Run-III
Summary Our Japanese Kaon Colleagues are using a step-by-step approach E391a hopes to reach the Grossman-Nir bound with the accumulated data (still two orders of magnitude from SM) E391a made some progress w.r.t. KAON2005 Neutron background must be handled In the longer term: Aim to measure ~100 SM K0L p0 nn at J-PARC Phase II by 2015 if Phase I is successful Proposal for J-PARC Phase I due by end of April 2006 No firm plans for K+ E949 detector may be used for penta-quark searches) They are looking for collaborators (as P-326 do!)