47,216 research outputs found

    Source of CP Violation for the Baryon Asymmetry of the Universe

    Full text link
    We give a description of why the existence of a fourth generation is likely to provide enough CP violation for baryogenesis, and trace how this observation came about. We survey the current experimental and theoretical pursuits and outline a research agenda, touching upon unitarity violation and very heavy chiral quarks, and comment on how the electroweak phase transition picture might be altered.Comment: Invited talk presented at 2nd International Workshop on Dark Matter, Dark Energy and Matter-antimatter Asymmetry, Hsinchu, Taiwan, November 5-6, 201

    Heavy QQ(bar) "Fireball" Annihilation to Multiple Vector Bosons

    Full text link
    Drawing analogy of replacing the nucleon by heavy chiral quark QQ, the pion by Goldstone boson GG, and πNN\pi NN coupling by GQQGQQ coupling, we construct a statistical model for QQˉ→nGQ\bar Q \to nG annihilation, i.e. into nn longitudinal weak bosons. This analogy is becoming prescient since the LHC direct bound mQ>611m_Q > 611 GeV implies strong Yukawa coupling. Taking mQ∈(1,2)m_Q \in (1, 2) TeV, the mean number ranges from 6 to over 10, with negligible two or three boson production. With individual t′t' or b′b' decays suppressed either by phase space or quark mixing, and given the strong Yukawa coupling, QQˉ→nVLQ\bar Q\to nV_L is the likely outcome for very heavy QQˉQ\bar Q production at the LHC.Comment: 4 pages, 1 figur

    Fourth Generation -- Towards Effect of Large Yukawa Coupling

    Get PDF
    In this talk we cover two threads regarding the 4th generation: on CP violation, from Earth up to the Heavens, i.e. from accelerator-based experimental studies, towards baryon asymmetry of the Universe; and on direct search bounds on mt′m_{t'} and mb′m_{b'}, towards the possibility of electroweak symmetry breaking through large Yukawa couplings. Prospects and discussions are presented.Comment: Plenary talk presented at TOP2010, May 31 - June 4, 2010, Bruges, Belgiu

    What Can We Learn from Charmless Rare B Decays - the Past/Next 3 Years

    Get PDF
    A personal perspective is given on physics of charmless rare B decays: 1997 -- 2003.Comment: 6 pages, 2 eps figures included. Invited talk presented at joint session of the 8th Asia Pacific Physics Conference (APPC 2000) and 3rd ACFA Workshop on Physics/Detector at the Linear Collider (ACFA-LC3), Taipei, Taiwan, August 200

    Indications for Large Rescattering in Rare B Decays

    Full text link
    The sign of ACP(K−π+)<0A_{\rm CP}(K^-\pi^+) < 0, the evidence for Bˉ0→π0π0\bar B^0 \to \pi^0\pi^0, and the possibly sizable AππA_{\pi\pi} and SππS_{\pi\pi} in Bˉ0→π+π−\bar B^0 \to \pi^+\pi^- all suggest that final state rescattering may be needed in Bˉ→PP\bar B\to PP decay, which is echoed by large color suppressed Bˉ0→D0h0\bar B^0\to D^0h^0 modes. An SU(3) formalism of 8⊗8→8⊗8{\bf 8}\otimes {\bf 8} \to {\bf 8}\otimes {\bf 8} rescattering in PPPP final states leads to interesting predictions, in particular allowing for small Bˉ0→K−K+\bar B^0 \to K^-K^+.Comment: 3 pages, 3 figures. Talk presented at EPS2003 Conference, Aachen, Germany, July 200
    • …
    corecore