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Related papers: Prospects for PIONEER

200 papers

Hadronic matrix elements of proton decay are essential ingredients to bridge the grand unification theory to low energy observables like proton lifetime. In this paper we non-perturbatively calculate the matrix elements, relevant for the…

High Energy Physics - Lattice · Physics 2014-01-22 Y. Aoki , E. Shintani , A. Soni

We report new experimental limits on the \pi^0 -> \gamma X decay of the neutral pion into a photon and a light boson X followed by the decay X -> e+e-. If this process exist, one would expect a flux of high energy X's produced from \pi^0's…

High Energy Physics - Phenomenology · Physics 2012-03-30 S. N. Gninenko

We have searched for the pion decay pi^+ --> mu^+ X, where X is a neutral particle of mass 33.905 MeV. This process was suggested by the KARMEN Collaboration to explain an anomaly in their observed time distribution of neutrino induced…

High Energy Physics - Experiment · Physics 2008-11-26 M. Daum , M. Janousch , P-R. Kettle , J. Koglin , D. Pocanic , J. Schotmueller , C. Wigger , Z. G. Zhao

We develop the perturbative QCD formalism including Sudakov effects for semi-leptonic $B$ meson decays. We evaluate the differential decay rate of $B\to \pi l \nu$, and find that the perturbative calculation is reliable for the energy…

High Energy Physics - Phenomenology · Physics 2010-11-01 Hsiang-nan Li , Hoi-Lai Yu

Strong pionic decays of baryons are studied in a non-relativistic quark model framework via a convergent (p/E) expansion of the transition operator. Results are compared to the ones obtained within a more conventional (p/m) expansion.

Nuclear Theory · Physics 2009-10-30 F. Cano , P. Gonzalez , B. Desplanques , S. Noguera

The vector form factor of the decay $\pi^{+} \rightarrow \gamma + e^{+} + \nu_e$ is calculated by the method for the pseudovector pion-nucleon system. The non-perturbative term is taken into account by using the parameter for the…

High Energy Physics - Phenomenology · Physics 2025-06-04 Susumu Kinpara

We review the physics of purely leptonic decays of $\pi^\pm$, $K^\pm$, $D^{\pm}$, $D_s^\pm$, and $B^\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of…

High Energy Physics - Experiment · Physics 2013-09-13 Jonathan L. Rosner , Sheldon Stone

We review the physics of purely leptonic decays of $\pi^\pm$, $K^\pm$, $D^{\pm}$, $D_s^\pm$, and $B^\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of…

High Energy Physics - Phenomenology · Physics 2016-03-10 Jonathan L. Rosner , Sheldon Stone , Ruth S. Van de Water

The three body pion decays ${\pi}^+{\rightarrow}l^+{\nu}X~(l=e,{\mu})$, where $X$ is a weakly interacting neutral boson, were searched for using the full data set from the PIENU experiment. An improved limit on…

Independent of assumptions about the form of the quark-antiquark scattering kernel we derive the explicit relation between the pion Bethe-Salpeter amplitude, Gamma_pi, and the quark propagator in the chiral limit; Gamma_pi necessarily…

Nuclear Theory · Physics 2010-03-04 P. Maris , C. D. Roberts , P. C. Tandy

We review the physics of purely leptonic decays of $\pi^\pm$, $K^\pm$, $D^{\pm}$, $D_s^\pm$, and $B^\pm$ pseudoscalar mesons. The measured decay rates are related to the product of the relevant weak-interaction-based CKM matrix element of…

High Energy Physics - Experiment · Physics 2010-04-22 Jonathan L. Rosner , Sheldon Stone

We study the radiative $\phi$ decay into $\pi^0 \pi^0 \gamma$ and $\pi^0 \eta \gamma $ taking into account mechanisms in which there are two sequential vector-vector-pseudoscalar or axial-vector--vector--pseudoscalar steps followed by the…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. E. Palomar , L. Roca , E. Oset , M. J. Vicente Vacas

It is well known that neutrinoless double decay is going to play a crucial role in settling the neutrino properties, which cannot be extracted from the neutrino oscillation data. It is, in particular, expected to settle the absolute scale…

High Energy Physics - Phenomenology · Physics 2010-04-06 J. D. Vergados , Amand Faessler , H. Toki

We give an overview of direct determinations of the angles of the unitarity triangle of the CKM matrix, using CP-violating effects in B-meson decays. After a discussion of B --> pi K modes, which can be described efficiently through allowed…

High Energy Physics - Phenomenology · Physics 2010-11-23 Robert Fleischer

We calculate the decays of baryon resonances to the pion + Roper resonance channel in the frame of the flux-tube breaking model. The baryon and meson wavefunctions we use are obtained from a linear confinement semi-relativistic constituent…

Nuclear Theory · Physics 2007-05-23 Pierre Stassart

Heavy neutrinos were sought in pion decays $\pi^+ \rightarrow \mu^+ \nu$ by examining the observed muon energy spectrum for extra peaks in addition to the expected peak for a massless neutrino. No evidence for heavy neutrinos was observed.…

The arguments are put forward that the many pion decays omega ->2 pi^+ 2 pi^- pi^0 and pi^+ pi^- 3 pi^0 provide an ideal test site for testing the predictions of chiral models of the vector meson decays into many pions. Using the approach…

High Energy Physics - Phenomenology · Physics 2009-10-31 N. N. Achasov , A. A. Kozhevnikov

Precision studies of $0^{+} \rightarrow 0^{+}$ superallowed $\beta$ decays provide the necessary data to test stringently the CVC hypothesis. They will also provide a value for the weak vector coupling constant and the $V_{ud}$ quark mixing…

Nuclear Experiment · Physics 2007-05-23 E. Hagberg , J. C. Hardy , V. T. Koslowsky , G. Savard , I. S. Towner

Asymmetric e^+e^- colliders running on the \Upsilon(4S) (B factories) will much more readily measure CP-violating asymmetries in the decays of B_d^0 and B^\pm mesons than in the decays of B_s^0 mesons. As such, they will seemingly not be…

High Energy Physics - Phenomenology · Physics 2010-11-23 David London , Amarjit Soni

We study the decays $\pi^{+}\to l^{+}\nu_{l}$ in the presence of a background electromagnetic plane wave with circular polarization. We find that, in the presence of this background, the number of hadronic form factors required to describe…

High Energy Physics - Phenomenology · Physics 2025-09-25 D. Gomez Dumm , S. Noguera , N. N. Scoccola