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Related papers: On Unparticles and K+ to pi+ Missing Energy

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Pion-kaon ($\pi K$) pairs occur frequently as final states in heavy-particle decays. A consistent treatment of $\pi K$ scattering and production amplitudes over a wide energy range is therefore mandatory for multiple applications: in…

High Energy Physics - Phenomenology · Physics 2021-05-19 Leon von Detten , Frederic Noël , Christoph Hanhart , Martin Hoferichter , Bastian Kubis

Decays $K^{+} \rightarrow \mu^{+}\nu_{\mu} \nu \bar \nu$ and $K^{+}\rightarrow e^{+}\nu_{e} \nu \bar \nu$ are examined to the leading order in momenta in the framework of Chiral Perturbation Theory. Predictions of the Standard Model for the…

High Energy Physics - Phenomenology · Physics 2016-11-03 D. Gorbunov , A. Mitrofanov

The rare K -> pi nu anti-nu decays play a central role in testing the Standard Model and its extensions. Upcoming experiments plan to measure the decay rates with high accuracy. Yet, unknown higher-order electroweak corrections result in a…

High Energy Physics - Phenomenology · Physics 2011-03-02 Joachim Brod , Martin Gorbahn , Emmanuel Stamou

A sample of 65210 $\mathrm{K^{\pm}} \rightarrow \pi^{0} \pi^{0} \mathrm{e^{\pm}} \nu$ ($\mathrm{K}_{\mathrm{e}4}^{00}$) decay candidates with $1\%$ background contamination has been collected in 2003$-$2004 by the NA48/2 collaboration at…

High Energy Physics - Experiment · Physics 2014-08-29 2 Collaboration

Conceivable explanations of Belle-II measurements of a (surprising) excess of missing-energy decays of the $B$ meson to the $K$ meson not covered by standard-model neutrino-antineutrino pairs might be offered by additional contributions of…

High Energy Physics - Phenomenology · Physics 2025-12-01 Alexander Berezhnoy , Wolfgang Lucha , Dmitri Melikhov

We show a natural form of the interaction between unparticle and supersymmetry. Using the couplings of unparticle to supersymmetry presented, as examples, we calculate the differential decay rates for the processes ${\it {\tilde f}}\to {\it…

High Energy Physics - Phenomenology · Physics 2008-11-26 Hao Zhang , Chong Sheng Li , Zhao Li

The form factors of the $K^+ \to \gamma$ transition are studied in the light-front quark model and chiral perturbation theory of $O(p^6)$. The decay spectrum of $K^+ \to e^+ \nu_{e}\gamma$, dominated by the structure dependent contribution,…

High Energy Physics - Phenomenology · Physics 2008-11-26 C. H. Chen , C. Q. Geng , C. C. Lih

E865 at the Brookhaven National Laboratory AGS collected about 70,000 K+(e3) events to measure the K+(e3) branching ratio relative to the observed K+ -> pi+ pi0, K+ -> pi0 mu+ nu, and K+ -> pi+ pi0 decays. The pi0 in all the decays was…

High Energy Physics - Experiment · Physics 2007-05-23 A. A. Poblaguev

We examine the possible unparticle effects on $R(D^{(*)})$ associated with $B\to D^{(*)}\tau\nu$ decays by minimum-$\chi^2$ fitting. Recent measurements from Belle and LHCb are included in this analysis. While it is true that the new…

High Energy Physics - Phenomenology · Physics 2018-10-08 Jong-Phil Lee

We investigate the possibility of disentangling different new physics contributions to the rare meson decays $K\rightarrow\pi+\displaystyle{\not}E$ and $B\rightarrow K(K^*)+\displaystyle{\not}E$ through kinematic distributions in the…

High Energy Physics - Phenomenology · Physics 2024-10-14 Andrzej J. Buras , Julia Harz , Martin A. Mojahed

We calculate the S-wave decay widths and energy shifts for pi pi and pi K atoms in the framework of QCD+QED. The evaluation - valid at next-to-leading order in isospin symmetry breaking - is performed within a non-relativistic effective…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. Schweizer

We analyze in the four-generation model the first measurement of the branching ratio of rare kaon decay K^+\to\pi^+\nu\bar{\nu}, using the constraints from \Delta m_K, \epsilon_K, B_d-\bar{B_d} mixing, \Gamma (b\to s\gamma), B_s-\bar{B_s}…

High Energy Physics - Phenomenology · Physics 2009-09-25 T. Hattori , T. Hasuike , S. Wakaizumi

We investigate the $D_{s}^{+} \rightarrow K^{+} K^{-} \pi^{+}$ decay theoretically with the final state interactions, which is based on the chiral unitary approach and takes into account the external and internal $W$-emission mechanisms at…

High Energy Physics - Phenomenology · Physics 2022-03-22 Zhong-Yu Wang , Jing-Yu Yi , Zhi-Feng Sun , C. W. Xiao

We examine a dark energy model where a scalar unparticle degree of freedom plays the role of quintessence. In particular, we study a model where the unparticle degree of freedom has a standard kinetic term and a simple mass potential, the…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 De-Chang Dai , Sourish Dutta , Dejan Stojkovic

The rare $K \to \pi \nu \bar{\nu}$ decay modes and the parameter $\epsilon_K$ that measures CP violation in Kaon mixing are sensitive probes of physics beyond the standard model. In this article we provide the updated standard-model…

High Energy Physics - Phenomenology · Physics 2021-05-07 Joachim Brod , Martin Gorbahn , Emmanuel Stamou

The amplitudes for the rare decay modes $K^\pm\to\pi^\pm\ell^+\ell^-$ and $K_S\to\pi^0\ell^+\ell^-$ are studied with the aim of obtaining predictions for them, such as to enable the possibility to search for violations of lepton-flavour…

High Energy Physics - Phenomenology · Physics 2019-07-02 Giancarlo D'Ambrosio , David Greynat , Marc Knecht

We present a model independent analysis of new-physics contributions to the decays K^+ \to \pi^+ \nu \bar \nu and K_L \to \pi^0 \nu \bar \nu. We parameterize the effects of new physics in these decays by two parameters: r_K and \theta_K,…

High Energy Physics - Phenomenology · Physics 2009-10-30 A. J. Buras , A. Romanino , L. Silvestrini

We have performed a search for the angular-momentum forbidden decay K+ -> pi+ gamma with the E787 detector at BNL. No events were observed in the pi+ kinematic region around 227 MeV/c. An upper limit on the branching ratio for the decay is…

High Energy Physics - Experiment · Physics 2012-08-27 E787 Collaboration

We have examined the decay $K^0_L \to \pi^0 \mu^+ \mu^-$ in which the branching ratio, the muon energy asymmetry and the muon decay asymmetry could be measured. In particular, we find that within the Standard Model the longitudinal…

High Energy Physics - Phenomenology · Physics 2009-11-07 Milind V. Diwan , Hong Ma , T. L. Trueman