# (A)symmetries of weak decays at and near the kinematic endpoint

@article{Hiller2013AsymmetriesOW,
title={(A)symmetries of weak decays at and near the kinematic endpoint},
author={Gudrun Hiller and Roman Zwicky},
journal={Journal of High Energy Physics},
year={2013},
volume={2014},
pages={1-33}
}
• Published 6 December 2013
• Physics
• Journal of High Energy Physics
A bstractAt the kinematic endpoint of zero recoil physical momenta are parallel which leads to symmetries in the decay distributions. We implement this observation for decays of the type A → (B1B2)C by extending the helicity formalism to include an unphysical timelike polarisation. The symmetries of the helicity amplitudes are worked out for a generic dimension six Hamiltonian for a B → V ℓℓ decay type. We obtain exact predictions for angular observables, e.g., for the fraction of…

### Time dependence in B → V ℓℓ decays

• Physics
• 2015
A bstractWe discuss the theory and phenomenology of Bd,s → V (→ M1M2)ℓℓ decays in the presence of neutral-meson mixing. We derive expressions for the time-dependent angular distributions for decays

### Endpoint symmetries of helicity amplitudes

We investigate helicity amplitudes (HAs) of $A \to B C$-type decays for arbitrary spin towards the kinematic endpoint. We show that they are proportional to product of Clebsch-Gordan coefficients

### Rare radiative and semileptonic B meson decays

Recent results at the LHCb and B-factory experiments have suggested that rare processes in B → V γ and B → V  ̄̀ decays, where V is a vector meson, show some deviation from Standard Model

### B → K ∗ ν ν ¯ decays in the Standard Model and beyond

• Physics
• 2015
The rare decay B → K∗(→ Kπ)μμ is regarded as one of the crucial channels for B physics as the polarization of the K allows a precise angular reconstruction resulting in many observables that offer

### Probing the standard model with rare charm decays

This thesis comprises a study of rare charm decays in the standard model (SM) and beyond. Within an effective theory framework, we calculate the SM Wilson coefficients to (partly) next-to-next-to

### Generalised helicity formalism , higher moments and the B → K J K ( → Kπ ) ̄̀ 1  2 angular distributions

• Physics
• 2018
We generalise the Jacob-Wick helicity formalism, which applies to sequential decays, to effective field theories of rare decays of the type B → KJK (→ Kπ) ̄̀1`2. This is achieved by reinterpreting

### New physics in b → s transitions after LHC run 1

• Physics
• 2015
We present results of global fits of all relevant experimental data on rare b → s decays. We observe significant tensions between the Standard Model predictions and the data. After critically

### in the Standard Model from light-cone sum rules

• Physics
• 2016
We present Bq → ρ, Bq → ω, Bq → K∗, Bs → K∗ and Bs → φ form factors from light-cone sum rules (LCSR) at O(αs) for twist-2 and 3 and O(α0 s) for twist-4 with updated hadronic input parameters. Three

### University of Birmingham Observation of the decay B-0s (2S)K+-LHCb

• Physics
• 2016
The decay B 0 s → ψ( 2 S ) K + π − is observed using a data set corresponding to an integrated luminosity of 3 . 0 fb − 1 collected by the LHCb experiment in pp collisions at centre-of-mass energies

### Helicity Amplitudes and Angular Decay Distributions

I discuss how to obtain angular decay distributions for sequential cascade decays using helicity methods. The angular decay distributions follow from a reasonably simple master formula involving

## References

SHOWING 1-10 OF 106 REFERENCES

### Endpoint symmetries of helicity amplitudes

We investigate helicity amplitudes (HAs) of $A \to B C$-type decays for arbitrary spin towards the kinematic endpoint. We show that they are proportional to product of Clebsch-Gordan coefficients

### Polarization in B → V V Decays

• Physics
• 2004
Factorizable amplitudes in B decays to light vector meson pairs give a longitudinal polarization satisfying 1 − fL = O(1/mb ). This remains formally true when nonfactorizable graphs are included in

### Angular distributions of B̄ → Kl̄l decays

• Physics
• 2007
We model-independently analyze the angular distributions of → Kl decays, l = e,μ, for low dilepton mass using QCD factorization. Besides the decay rate, we study the forward-backward asymmetry AlFB

### The effect of S-wave interference on the B0→ K∗0ℓ+ℓ− angular observables

• Physics
• 2012
A bstractThe rare decay B0→ K∗0ℓ+ℓ− is a flavour changing neutral current decay with a high sensitivity to physics beyond the Standard Model. Nearly all theoretical predictions and all experimental

### A Comparative Study of the Decays B → ( K , K ∗ ) l + l − in Standard Model and Supersymmetric Theories

• Physics
• 1999
Using improved theoretical calculations of the decay form factors in the Light Cone-QCD sum rule approach, we investigate the decay rates, dilepton invariant mass spectra and the forward-backward

### Symmetries and Asymmetries of B -> K* mu+ mu- Decays in the Standard Model and Beyond

• Physics
• 2008
The rare decay B → K*(→ Kπ)μ+μ− is regarded as one of the crucial channels for B physics as the polarization of the K* allows a precise angular reconstruction resulting in many observables that offer

### B! K l + l decays at low recoil

• Physics
• 2010
Using the heavy quark eective theory framework put forward by Grinstein and Pirjol we work out predictions for B! K l + l , l = e; , decays for a softly recoiling K , i.e., for large dilepton masses

### New physics in B→K∗μμ?

• Physics
• 2013
Recent experimental results on angular observables in the rare decay B→K∗μ+μ− show significant deviations from Standard Model predictions. We investigate the possibility that these deviations are due