Amplitude analysis of the B + → D + D − K + decay

Elastic scattering amplitudes for I = 0 DK and I = 0, 1 $$ D\overline{K} $$ D K ¯ are computed in S, P and D partial waves using lattice QCD with light-quark masses corresponding to mπ = 239 MeV and mπ = 391 MeV. The S-waves contain interesting features including a near-threshold JP = 0+ bound state in I = 0 DK, corresponding to the $$ {D}_{s0}^{\ast } $$ D s 0 ∗ (2317), with an effect that is clearly visible above threshold, and suggestions of a 0+ virtual bound state in I = 0 $$ D\overline{K} $$ D K ¯ . The S-wave I = 1 $$ D\overline{K} $$ D K ¯ amplitude is found to be weakly repulsive. The computed finite-volume spectra also contain a deeply-bound D* vector resonance, but negligibly small P -wave DK interactions are observed in the energy region considered; the P and D-wave $$ D\overline{K} $$ D K ¯ amplitudes are also small. There is some evidence of 1+ and 2+ resonances in I = 0 DK at higher energies.

Section: Dk Scattering In I =mentioning

confidence: 94%

“…An axial-vector state, D s1 (2460), was also discovered [4] and similarly does not fit easily into expectations based on a quark model. While this article was being finalised, LHCb announced the observation of a structure in the exotic-flavour D − K + (csdu) channel at an energy ∼ 2.9 GeV [5][6][7].…”

Section: Jhep02(2021)100mentioning

confidence: 99%

DK I = 0, $$ D\overline{K} $$ I = 0, 1 scattering and the $$ {D}_{s0}^{\ast } $$(2317) from lattice QCD

Cheung

Thomas

Wilson

et al. 2021

“…In the energy region around 3.9 GeV, above the threshold, one expects a corresponding excited state. So far, three hadrons have been observed with the possible assignment of J P C = 0 ++ : the X(3860), a broad resonance detected by Belle [1,2], and two narrow resonances just below the D sDs threshold -the χ c0 (3930) discovered in the DD channel by LHCb [3,4] and the X(3915) observed through it's decay into J/ψω [5][6][7][8] (with the assignment of J P C = 0 ++ or 2 ++ ). While the latter two resonances could be the same state, their narrowness may indicate exotic content, where X(3915) has been interpreted as ccss meson in ref.…”

Section: Introductionmentioning

confidence: 99%

Charmonium-like resonances with JPC = 0++, 2++ in coupled $$ \mathrm{D}\overline{\mathrm{D}} $$, $$ {\mathrm{D}}_{\mathrm{s}}{\overline{\mathrm{D}}}_{\mathrm{s}} $$ scattering on the lattice

Prelovšek

Collins

Mohler

et al. 2021

We present the first lattice investigation of coupled-channel $$ D\overline{D} $$ D D ¯ and $$ {D}_s{\overline{D}}_s $$ D s D ¯ s scattering in the JPC = 0++ and 2++ channels. The scattering matrix for partial waves l = 0, 2 and isospin zero is determined using multiple volumes and inertial frames via Lüscher’s formalism. Lattice QCD ensembles from the CLS consortium with mπ ≃ 280 MeV, a ≃ 0.09 fm and L/a = 24, 32 are utilized. The resulting scattering matrix suggests the existence of three charmonium-like states with JPC = 0++ in the energy region ranging from slightly below 2mD up to 4.13 GeV. We find a so far unobserved $$ D\overline{D} $$ D D ¯ bound state just below threshold and a $$ D\overline{D} $$ D D ¯ resonance likely related to χc0(3860), which is believed to be χc0(2P). In addition, there is an indication for a narrow 0++ resonance just below the $$ {D}_s{\overline{D}}_s $$ D s D ¯ s threshold with a large coupling to $$ {D}_s{\overline{D}}_s $$ D s D ¯ s and a very small coupling to $$ D\overline{D} $$ D D ¯ . This resonance is possibly related to the narrow X(3915)/χc0(3930) observed in experiment also just below $$ {D}_s{\overline{D}}_s $$ D s D ¯ s . The partial wave l = 2 features a resonance likely related to χc2(3930). We work with several assumptions, such as the omission of J/ψω, ηcη and three-particle channels. Only statistical uncertainties are quantified, while the extrapolations to the physical quark-masses and the continuum limit are challenges for the future.

“…The systematic uncertainty obtained through this procedure arises from the kernel shape used in the estimation of the probability density distributions. An alternative combined response is estimated using an alternative kernel estimation with a changed shape and the efficiency models are regenerated [42,43]. The difference between the two estimates for the efficiency ratios is taken as the systematic uncertainty related to hadron identification and is found to be 0.3% in the ratio R π/K .…”

Section: Jhep05(2021)095mentioning

confidence: 99%

Observation of the decay $$ {\Lambda}_{\mathrm{b}}^0 $$ → χc1pπ−

Aaij¹,

Beteta²,

Ackernley³

et al. 2021

Self Cite

The Cabibbo-suppressed decay $$ {\Lambda}_{\mathrm{b}}^0 $$ Λ b 0 → χc1pπ− is observed for the first time using data from proton-proton collisions corresponding to an integrated luminosity of 6 fb−1, collected with the LHCb detector at a centre-of-mass energy of 13 TeV. Evidence for the $$ {\Lambda}_{\mathrm{b}}^0 $$ Λ b 0 → χc2pπ− decay is also found. Using the $$ {\Lambda}_{\mathrm{b}}^0 $$ Λ b 0 → χc1pK− decay as normalisation channel, the ratios of branching fractions are measured to be$$ {\displaystyle \begin{array}{c}\frac{\mathcal{B}\left({\Lambda}_{\mathrm{b}}^0\to {\upchi}_{\mathrm{c}1}{\mathrm{p}\uppi}^{-}\right)}{\mathcal{B}\left({\Lambda}_{\mathrm{b}}^0\to {\upchi}_{\mathrm{c}1}{\mathrm{p}\mathrm{K}}^{-}\right)}=\left(6.59\pm 1.01\pm 0.22\right)\times {10}^{-2},\\ {}\frac{\mathcal{B}\left({\Lambda}_{\mathrm{b}}^0\to {\upchi}_{\mathrm{c}2}{\mathrm{p}\uppi}^{-}\right)}{\mathcal{B}\left({\Lambda}_{\mathrm{b}}^0\to {\upchi}_{\mathrm{c}1}{\mathrm{p}\uppi}^{-}\right)}=0.95\pm 0.30\pm 0.04\pm 0.04,\\ {}\frac{\mathcal{B}\left({\Lambda}_{\mathrm{b}}^0\to {\upchi}_{\mathrm{c}2}{\mathrm{p}\mathrm{K}}^{-}\right)}{\mathcal{B}\left({\Lambda}_{\mathrm{b}}^0\to {\upchi}_{\mathrm{c}1}{\mathrm{p}\mathrm{K}}^{-}\right)}=1.06\pm 0.05\pm 0.04\pm 0.04,\end{array}} $$ B Λ b 0 → χ c 1 pπ − B Λ b 0 → χ c 1 pK − = 6.59 ± 1.01 ± 0.22 × 10 − 2 , B Λ b 0 → χ c 2 pπ − B Λ b 0 → χ c 1 pπ − = 0.95 ± 0.30 ± 0.04 ± 0.04 , B Λ b 0 → χ c 2 pK − B Λ b 0 → χ c 1 pK − = 1.06 ± 0.05 ± 0.04 ± 0.04 , where the first uncertainty is statistical, the second is systematic and the third is due to the uncertainties in the branching fractions of χc1,2→ J/ψγ decays.