The 2004 UTfit Collaboration Report on the Status of the Unitarity Triangle in the Standard Model

Using the latest determinations of several theoretical and experimental parameters, we update the Unitarity Triangle analysis in the Standard Model. The basic experimental constraints come from the measurements of |V_ub/V_cb|, Delta M_d, the lower limit on Delta M_s, epsilon_k, and the measurement of the phase of the B_d - anti B_d mixing amplitude through the time-dependent CP asymmetry in B^0 to J/psi K^0 decays. In addition, we consider the direct determination of alpha, gamma, 2 beta + gamma and cos(2 beta) from the measurements of new CP-violating quantities, recently performed at the B factories. We also discuss the opportunities offered by improving the precision of the various physical quantities entering in the determination of the Unitarity Triangle parameters. The results and the plots presented in this paper can also be found at http://www.utfit.org, where they are continuously updated with the newest experimental and theoretical results.Comment: 32 pages, 17 figures. High resolution figures and updates can be found at http://www.utfit.org v2: misprints correcte

Phenomenological Constraints on Extended Quark Sectors

We study the flavor physics in two extensions of the quark sector of the Standard Model (SM): a four generation model and a model with a single vector--like down--type quark (VDQ). In our analysis we take into account the experimental constraints from tree--level charged current processes, rare Kaon decay processes, rare B decay processes, the $Z\to b \bar{b}$ decay, $K$, $B$ and $D$ mass differences, and the CP violating parameters \frac \epsilon^\prime}{\epsilon}, $\epsilon_K$ and $a_{\psi K}$. All the constraints are taken at two sigma. We find bounds on parameters which can be used to represent the New Physics contributions in these models ($\lambda_{t^ \prime}^{bd}$, $\lambda_{t^ \prime}^{bs}$ and $\lambda_{t^ \prime}^{sd}$ in the four--generation model, and $U_{bd}$, $U_{bs}$ and $U_{sd}$ in the VDQ model) due to all the above constraints. In both models the predicted ranges for $a_{SL}$ (the CP asymmetry in semi-leptonic decays), $\Delta M_D$, $B(K^+\to\pi^+ \nu \bar{\nu})$, $B(K_L\to\pi^0 \nu \bar{\nu})$ and $B(K_L\to \mu \bar{\mu})_{SD}$ can be significantly higher than the predictions of the SM, while the allowed ranges for $a_{\psi K}$ and for $\Delta m_{B_S}$ are consistent with the SM prediction.Comment: 22 pages, 5 figures (v3: added a reference, updated a reference, added missing units

B_{s,d} -> l^+ l^- and K_L -> l^+ l^- in SUSY models with non-minimal sources of flavour mixing

We present a general analysis of B_{s,d}-> l^+ l^- and K_L -> l^+ l^- decays in supersymmetric models with non-minimal sources of flavour mixing. In spite of the existing constraints on off-diagonal squark mass terms, these modes could still receive sizeable corrections, mainly because of Higgs-mediated FCNCs arising at large tan(beta). The severe limits on scenarios with large tan(beta) and non-negligible {tilde d}^i_{R(L)}-{d-tilde}^j_{R(L)} mixing imposed by the present experimental bounds on these modes and Delta B=2 observables are discussed in detail. In particular, we show that scalar-current contributions to K_L -> l^+ l^- and B-{bar B} mixing set non-trivial constraints on the possibility that B_s -> l^+ l^- and B_d -> l^+ l^- receive large corrections.Comment: 18 pages, 4 figures (v2: minor changes, published version

Fully-parallel quantum turbo decoder

Quantum Turbo Codes (QTCs) are known to operate close to the achievable Hashing bound. However, the sequential nature of the conventional quantum turbo decoding algorithm imposes a high decoding latency, which increases linearly with the frame length. This posses a potential threat to quantum systems having short coherence times. In this context, we conceive a Fully- Parallel Quantum Turbo Decoder (FPQTD), which eliminates the inherent time dependencies of the conventional decoder by executing all the associated processes concurrently. Due to its parallel nature, the proposed FPQTD reduces the decoding times by several orders of magnitude, while maintaining the same performance. We have also demonstrated the significance of employing an odd-even interleaver design in conjunction with the proposed FPQTD. More specifically, it is shown that an odd-even interleaver reduces the computational complexity by 50%, without compromising the achievable performance

Direct CP Violation, Branching Ratios and Form Factors B→πB \to \pi, B→KB \to K in BB Decays

The $B \to \pi$ and $B \to K$ transitions involved in hadronic B decays are investigated in a phenomenological way through the framework of QCD factorization. By comparing our results with experimental branching ratios from the BELLE, BABAR and CLEO Collaborations for all the B decays including either a pion or a kaon, we propose boundaries for the transition form factors $B \to \pi$ and $B \to K$ depending on the CKM matrix element parameters $\rho$ and $\eta$. From this analysis, the form factors required to reproduce the experimental data for branching ratios are $F^{B \to \pi}= 0.31 \pm 0.12$ and $F^{B \to K}= 0.37\pm 0.13$. We calculate the direct CP violating asymmetry parameter, $a_{CP}$, for $B \to \pi^{+} \pi^{-} \pi$ and $B \to \pi^{+} \pi^{-} K$ decays, in the case where $\rho-\omega$ mixing effects are taken into account. Based on these results, we find that the direct CP asymmetry for $B^{-} \to \pi^{+} \pi^{-} \pi^{-}$, $\bar{B}^{0} \to \pi^{+} \pi^{-} \pi^{0}$, $B^{-} \to \pi^{+} \pi^{-} K^{-}$, and $\bar{B}^{0} \to \pi^{+} \pi^{-} \bar{K}^{0}$, reaches its maximum when the invariant mass $\pi^{+} \pi^{-}$ is in the vicinity of the $\omega$ meson mass. The inclusion of $\rho-\omega$ mixing provides an opportunity to erase, without ambiguity, the phase uncertainty mod$(\pi)$ in the determination of the CKM angles $\alpha$ in case of $b\to u$ and $\gamma$ in case of $b \to s$.Comment: 74 pages, 15 figures, 8 tables. A few misprints corrected, two references adde

BB-to-Glueball form factor and Glueball production in BB decays

We investigate transition form factors of $B$ meson decays into a scalar glueball in the light-cone formalism. Compared with form factors of $B$ to ordinary scalar mesons, the $B$-to-glueball form factors have the same power in the expansion of $1/m_B$. Taking into account the leading twist light-cone distribution amplitude, we find that they are numerically smaller than those form factors of $B$ to ordinary scalar mesons. Semileptonic $B\to Gl\bar\nu$, $B\to Gl^+l^-$ and $B_s\to Gl^+l^-$ decays are subsequently investigated. We also analyze the production rates of scalar mesons in semileptonic $B$ decays in the presence of mixing between scalar $\bar qq$ and glueball states. The glueball production in $B_c$ meson decays is also investigated and the LHCb experiment may discover this channel. The sizable branching fraction in $B_c\to (\pi^+\pi^-)l^-\bar\nu$, $B_c\to (K^+K^-)l^-\bar\nu$ or $B_c\to (\pi^+\pi^-\pi^+\pi^-)l^-\bar\nu$ could be a clear signal for a scalar glueball state.Comment: 17 pages, 3 figure, revtex

Charged-Lepton Flavour Physics

This writeup of a talk at the 2011 Lepton-Photon symposium in Mumbai, India, summarises recent results in the charged-lepton flavour sector. I review searches for charged-lepton flavour violation, lepton electric dipole moments and flavour-conserving CP violation. I also discuss recent progress in tau-lepton physics and in the Standard Model prediction of the muon anomalous magnetic moment.Comment: Presented at Lepton-Photon 2011, Mumbai, India; 23 pages, 14 figure

Present and Future CP Measurements

We review theoretical and experimental results on CP violation summarizing the discussions in the working group on CP violation at the UK phenomenology workshop 2000 in Durham.Comment: 104 pages, Latex, to appear in Journal of Physics

B \to K(K^*) missing energy in Unparticle physics

In the present work we study the effects of an unparticle \unpart as the possible source of missing energy in the decay $B \to K (K^*) + {\rm missing energy}$. We find that the dependence of the differential branching ratio on the $K$($K^*$)-meson's energy in the presence of the vector unparticle operators is very distinctive from that of the SM. Moreover, in using the existing upper bound on $B \to K (K^*) + {\rm missing energy}$ decays, we have been able to put more stringent constraints on the parameters of unparticle stuff.Comment: 13 pages, 5 figure

Study of pure annihilation type decays B→Ds∗KB \to D_s^{*} K

In this work, we calculate the rare decays $B^0 \to D_s^{*-} K^+$ and $B^+ \to D_s^{*+} \bar{K}^0$ in perturbative QCD approach with Sudakov resummation. We give the branching ratio of $10^{-5}$ for $B^0 \to D_s^{*-}K^+$, which will be tested soon in $B$ factories. The decay $B^+ \to D_s^{*+} \bar{K}^0$ has a very small branching ratio at ${\cal O}(10^{-8})$, due to the suppression from CKM matrix elements $|V_{ub}^* V_{cd}|$. It may be sensitive to new physics contributions.Comment: 14 pages, 1 figur