Dalitz plot analysis of the \(D^{+}\rightarrow K^{-}K^{+}K^{+}\) decay with the Multi-meson model
Sebastián Ordoñez-Soto
Universidad Nacional de Colombia
Supervisors: Alberto C. dos Reis and Diego Milanés
March 30th, 2022
Charm WG Meeting
Outline
- Introduction
- State of the Art
- Results from Run 1
- Analysis strategy
- Outlook
Introduction
- Decays of \(D\) mesons into three pseudoscalars are excellent laboratories to study light-meson spectroscopy.
- No tools for a description from first principles.
Motivation
Problem
- In a \(D\rightarrow K^{-}K^{+}K^{+}\) decay, the \(K\bar{K}\) scattering amplitudes can be determined.
- Need phenomenological models.
- The challenge:
- Dynamics: Heavy-quark weak transitions, hadron formation and final-state interactions (FSI)
- Strong part: effects of coupled channels, three-body interactions and isospin.
S. Ordoñez (UNAL-COL)
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
March 30, 2022
- Model based on chiral effective Lagrangians.
The Multi-meson model
- Model parameters have transparent physical meaning.
- The Triple-M has been developed to describe the \(D^{+}\rightarrow K^{-}K^{+}K^{+}\) decay.
- It has been already used in a Dalitz plot fit with data from the Run 1.
- It allows to obtain the \(K\bar{K}\) scattering amplitudes.
Introduction
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
March 30, 2022
S. Ordoñez (UNAL-COL)
State of the Art
[1]. [2018] First version of the model.
[2]. [2018] (PAPER-2018-039) Dalitz plot fit using the Multi-meson model decay amplitude.
[3]. [2020] Improved version of the Multi-meson model.
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
March 30, 2022
S. Ordoñez (UNAL-COL)
Results from Run 1
Figures taken from Ref. [2] (PAPER-2018-039)
Invariant-mass spectrum of the \(K^{-}K^{+}K^{+}\) candidates.
- 111 thousand candidates, of which \(90.45 \pm 0.07 \%\) correspond to signal
(left) Dalitz plot of the selected sample, including background. (right) Dalitz plot projections for candidates from regions I (blue) and II (red), above and below \(s_{K^{-}K^{+}}= 1.5\) GeV \(^{2}\).
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
March 30, 2022
S. Ordoñez (UNAL-COL)
Figure and table taken from Ref. [2] (PAPER-2018-039)
Results from Run 1
Relative fractions (%) of the various components of the Triple-M amplitude. The uncertainties correspond to the combined statistical and systematic uncertainties.
Projections of the Dalitz plot with the fit result with the Triple-M amplitude superimposed.
March 30, 2022
March 30, 2022
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
S. Ordoñez (UNAL-COL)
Figure taken from Ref. [2] (PAPER-2018-039)
Results from Run 1
(top) Phase-shifts \(\delta_{K^{+}K^{-}}^{0I}\) and (bottom) inelasticities \(\eta^{0I}\) as a function of the \(K^{+}K^{-}\) invariant mass, for both isospin states.
March 30, 2022
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
S. Ordoñez (UNAL-COL)
Analysis strategy
Perform a Dalitz plot analysis of the \(D^{+}\rightarrow K^{-}K^{+}K^{+}\) decay channel using the much larger data set of Run 2 and the improved version of the Multi-meson model.
Methodology
- GooFit
- Code the new version of the Triple-M amplitude
- Perform test with toys
- Simulations
- Large MC samples available
- Need to match data and MC distributions \(\rightarrow\) GB-Reweighting
- Data
- Sample used for the CPV search in \(D^{+}\rightarrow K^{-}K^{+}K^{+}\) has low purity: not adequate for DP analysis.
- New selection to be made
- Sample used for the CPV search in \(D^{+}\rightarrow K^{-}K^{+}K^{+}\) has low purity: not adequate for DP analysis.
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
March 30, 2022
S. Ordoñez (UNAL-COL)
Outlook
- GooFit
- Use existing GooFit classes to perform a DP fit of the \(D^{+}\rightarrow K^{-}K^{+}K^{+}\) decay.
- Next: Create a GooFit class corresponding to the first version of the Triple-M.
- Data
- Perform first tests with a small sample (2016)
- MVA selection
- Fits
- Significance and purity study
- Next: Pre-selection
- Perform first tests with a small sample (2016)
- Simulations
- Next: weights and GB-reweighting
\(D^{+}\rightarrow K^{-}K^{+}K^{+}\) Triple-M
March 30, 2022
S. Ordoñez (UNAL-COL)
Thank you!
Triple M - LHCb presentation
By Sebastian Ordoñez
