Chun-Khiang Chua

Chung Yuan Christian University

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Chung Yuan Christian University

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High Energy Physics

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Chun-Khiang Chua has a total of 31 co-authors. Here are the top co-authors by number of shared publications:

Hai-Yang Cheng
Institute of Physics, Academia Sinica, Taipei, Taiwan 115, Republic of China
28 shared publications
Wei-Shu Hou
Department of Physics, National Taiwan University, Taipei 10617, Taiwan, Republic of China, National Center for Theoretical Sciences, National Taiwan University, Taipei 10617, Taiwan, Republic of China
19 shared publications
Shang-Yuu Tsai
Institute of Physics, Academia Sinica Taipei, Taiwan 115, Republic of China
9 shared publications
Amarjit Soni
Physics Department, Brookhaven National Laboratory, Upton, New York 11973, USA
4 shared publications
Kwei-Chou Yang
4 shared publications
Gwo-Guang Wong
Department of Physics and Chung Yuan Center for High Energy Physics, Chung Yuan Christian University, Taoyuan, Taiwan 32023, Republic of China
3 shared publications

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Cited by 1
- 25 June 2026
- Published by American Physical Society (APS) in Physical Review D
Two-body charmed-anticharmed baryonic B decays
by Chun-Khiang Chua
We study the rates of two-body charmed-anticharmed baryonic B ¯ → B c B ¯ c decays using the topological amplitude approach. All amplitudes of B ¯ → B c ( 3 ¯ f ) B ¯ c ( 3 f ) , B c ( 6 f ) B ¯ c ( 3 f ) , B c ( 3 ¯ f ) B ¯ c ( 6 ¯ f ) , and B c ( 6 f ) B ¯ c ( 6 ¯ f ) decays are decomposed topologically. SU(3) breaking effects on these amplitudes, depending on the position of the s -quark line, are modeled. Using existing data as input, we obtained the following results: (i) In the low-lying B ¯ → B c ( 3 ¯ f ) B ¯ c ( 3 f ) decays, we find that the exchange diagram is sizable. Furthermore, there is a large cancellation between internal W -tree and exchange- W -tree amplitudes. The SU(3) breaking is sizable, 35% SU(3) breaking effects are needed, and they work differently in different amplitudes. Namely, the internal W -tree amplitude is enlarged, while the exchange- W -tree amplitude is reduced. The rates of B ¯ → B c ( 3 ¯ f ) B ¯ c ( 3 f ) decays with excited B c ( 3 ¯ f ) , such as Λ c ( 2595 ) + , Ξ c ( 2790 ) + , 0 , are also studied. (ii) The B ¯ → B c ( 6 f ) B ¯ c ( 3 f ) decays, with low-lying B ¯ c ( 3 f ) and low-lying and excited B c ( 6 f ) baryons, such as Σ c ( 2520 ) + , 0 , Ξ c ( 2645 ) + , 0 , Ω c ( 2770 ) 0 , are studied with some predictions on rates obtained. Furthermore, as the excited states are spin- 3 / 2 states, some of their rates are highly suppressed by the kinematic factor. (iii) The B ¯ → B c ( 3 ¯ f ) B ¯ c ( 6 ¯ f ) decays with low-lying charmed-anticharmed baryons are studied with some predictions on rates obtained. (iv) Uncertainties in most predicted rates are large, reflecting our current poor understanding of the related SU(3) breaking effects. Measuring these rates can provide very useful information about these effects.
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- 25 June 2026
- Published by American Physical Society (APS) in Physical Review D
Open Access
Two-body charmed-anticharmed baryonic B decays
by Chun-Khiang Chua
We study the rates of two-body charmed-anticharmed baryonic B ¯ → B c B ¯ c decays using the topological amplitude approach. All amplitudes of B ¯ → B c ( 3 ¯ f ) B ¯ c ( 3 f ) , B c ( 6 f ) B ¯ c ( 3 f ) , B c ( 3 ¯ f ) B ¯ c ( 6 ¯ f ) , and B c ( 6 f ) B ¯ c ( 6 ¯ f ) decays are decomposed topologically. SU(3) breaking effects on these amplitudes, depending on the position of the s -quark line, are modeled. Using existing data as input, we obtained the following results: (i) In the low-lying B ¯ → B c ( 3 ¯ f ) B ¯ c ( 3 f ) decays, we find that the exchange diagram is sizable. Furthermore, there is a large cancellation between internal W -tree and exchange- W -tree amplitudes. The SU(3) breaking is sizable, 35% SU(3) breaking effects are needed, and they work differently in different amplitudes. Namely, the internal W -tree amplitude is enlarged, while the exchange- W -tree amplitude is reduced. The rates of B ¯ → B c ( 3 ¯ f ) B ¯ c ( 3 f ) decays with excited B c ( 3 ¯ f ) , such as Λ c ( 2595 ) + , Ξ c ( 2790 ) + , 0 , are also studied. (ii) The B ¯ → B c ( 6 f ) B ¯ c ( 3 f ) decays, with low-lying B ¯ c ( 3 f ) and low-lying and excited B c ( 6 f ) baryons, such as Σ c ( 2520 ) + , 0 , Ξ c ( 2645 ) + , 0 , Ω c ( 2770 ) 0 , are studied with some predictions on rates obtained. Furthermore, as the excited states are spin- 3 / 2 states, some of their rates are highly suppressed by the kinematic factor. (iii) The B ¯ → B c ( 3 ¯ f ) B ¯ c ( 6 ¯ f ) decays with low-lying charmed-anticharmed baryons are studied with some predictions on rates obtained. (iv) Uncertainties in most predicted rates are large, reflecting our current poor understanding of the related SU(3) breaking effects. Measuring these rates can provide very useful information about these effects.
Cited by 1
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Cited by 1
- 8 October 2025
- Published by American Physical Society (APS) in Physical Review D
Heavy mesons to open-charmed tetraquark decays
by Chun-Khiang Chua
Motivated by the recent observations of T c s 0 * ( 2870 ) 0 , T c s ¯ 0 * ( 2900 ) 0 , and T c s ¯ 0 * ( 2900 ) + + open-charmed tetraquark states by LHCb, we study the decays of heavy mesons to these open-charmed tetraquark states ( T ) using a topological amplitude approach. We first obtain the T → D P and D S strong decay amplitudes by decomposing them into several topological amplitudes, where P is a light pseudoscalar particle and S is a low-lying scalar particle. Subsequently, weak decay amplitudes of B ¯ → D T ¯ , D ¯ T , B ¯ → T P , and T S decays are decomposed topologically. In addition, B c − → T T ¯ decays are also discussed. Using these results, modes with an unambiguous exotic interpretation in flavor are highlighted.
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- 8 October 2025
- Published by American Physical Society (APS) in Physical Review D
Open Access
Heavy mesons to open-charmed tetraquark decays
by Chun-Khiang Chua
Motivated by the recent observations of T c s 0 * ( 2870 ) 0 , T c s ¯ 0 * ( 2900 ) 0 , and T c s ¯ 0 * ( 2900 ) + + open-charmed tetraquark states by LHCb, we study the decays of heavy mesons to these open-charmed tetraquark states ( T ) using a topological amplitude approach. We first obtain the T → D P and D S strong decay amplitudes by decomposing them into several topological amplitudes, where P is a light pseudoscalar particle and S is a low-lying scalar particle. Subsequently, weak decay amplitudes of B ¯ → D T ¯ , D ¯ T , B ¯ → T P , and T S decays are decomposed topologically. In addition, B c − → T T ¯ decays are also discussed. Using these results, modes with an unambiguous exotic interpretation in flavor are highlighted.
Cited by 1
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Cited by 2
- 1 September 2023
- Published by American Physical Society (APS) in Physical Review D
Charmless semileptonic baryonic $B_{u, d, s}$ decays
by Chun-Khiang Chua
We study ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ and ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ decays with all low lying octet ( $B$ ) and decuplet ( $D$ ) baryons using a topological amplitude approach. In tree-induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ decay modes, we need two tree amplitudes and one annihilation amplitude in ${\bar{B}}_{q} \to B {\bar{B}}^{'} l \bar{ν}$ decays, one tree amplitude in ${\bar{B}}_{q} \to B \bar{D} l \bar{ν}$ decays, one tree amplitude in ${\bar{B}}_{q} \to D \bar{B} l \bar{ν}$ decays and one tree amplitude and one annihilation amplitude in ${\bar{B}}_{q} \to D {\bar{D}}^{'} l \bar{ν}$ decays. In loop induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ decay modes, similar numbers of penguin-box and penguin-box-annihilation amplitudes are needed. As the numbers of independent topological amplitudes are highly limited, there are plenty of relations on these semileptonic baryonic $B_{q}$ decay amplitudes. Furthermore, the loop topological amplitudes and tree topological amplitudes have simple relations, as their ratios are fixed by known Cabibbo-Kobayashi-Maskawa (CKM) factors and loop functions. It is observed that the $B^{-} \to p \bar{p} μ^{-} \bar{ν}$ differential rate exhibits threshold enhancement, which is expected to hold in all other semileptonic baryonic modes. The threshold enhancement effectively squeezes the phase space toward the threshold region and leads to very large SU(3) breaking effects in the decay rates. They are estimated using the measured $B^{-} \to p \bar{p} μ^{-} \bar{ν}$ differential rate and model calculations. From the model calculations, we find that branching ratios of nonannihilation ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ modes are of the orders of $10^{- 9} - 10^{- 6}$ , while branching ratios of nonpenguin-box-annihilation ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ modes are of the orders of $10^{- 12} - 10^{- 8}$ . Modes with relatively unsuppressed rates and good detectability are identified. These modes can be searched experimentally in near future and the rate estimations can be improved when more modes are discovered. Ratios of rates of some loop induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ decays and tree induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ decays are predicted and can be checked experimentally. They can be tests of the SM. Some implications on ${\bar{B}}_{q} \to B {\bar{B}}^{'} l^{+} l^{-}$ decays are also discussed.
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- 1 September 2023
- Published by American Physical Society (APS) in Physical Review D
Open Access
Charmless semileptonic baryonic $B_{u, d, s}$ decays
by Chun-Khiang Chua
We study ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ and ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ decays with all low lying octet ( $B$ ) and decuplet ( $D$ ) baryons using a topological amplitude approach. In tree-induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ decay modes, we need two tree amplitudes and one annihilation amplitude in ${\bar{B}}_{q} \to B {\bar{B}}^{'} l \bar{ν}$ decays, one tree amplitude in ${\bar{B}}_{q} \to B \bar{D} l \bar{ν}$ decays, one tree amplitude in ${\bar{B}}_{q} \to D \bar{B} l \bar{ν}$ decays and one tree amplitude and one annihilation amplitude in ${\bar{B}}_{q} \to D {\bar{D}}^{'} l \bar{ν}$ decays. In loop induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ decay modes, similar numbers of penguin-box and penguin-box-annihilation amplitudes are needed. As the numbers of independent topological amplitudes are highly limited, there are plenty of relations on these semileptonic baryonic $B_{q}$ decay amplitudes. Furthermore, the loop topological amplitudes and tree topological amplitudes have simple relations, as their ratios are fixed by known Cabibbo-Kobayashi-Maskawa (CKM) factors and loop functions. It is observed that the $B^{-} \to p \bar{p} μ^{-} \bar{ν}$ differential rate exhibits threshold enhancement, which is expected to hold in all other semileptonic baryonic modes. The threshold enhancement effectively squeezes the phase space toward the threshold region and leads to very large SU(3) breaking effects in the decay rates. They are estimated using the measured $B^{-} \to p \bar{p} μ^{-} \bar{ν}$ differential rate and model calculations. From the model calculations, we find that branching ratios of nonannihilation ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ modes are of the orders of $10^{- 9} - 10^{- 6}$ , while branching ratios of nonpenguin-box-annihilation ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ modes are of the orders of $10^{- 12} - 10^{- 8}$ . Modes with relatively unsuppressed rates and good detectability are identified. These modes can be searched experimentally in near future and the rate estimations can be improved when more modes are discovered. Ratios of rates of some loop induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} ν \bar{ν}$ decays and tree induced ${\bar{B}}_{q} \to {B \bar{B}}^{'} l \bar{ν}$ decays are predicted and can be checked experimentally. They can be tests of the SM. Some implications on ${\bar{B}}_{q} \to B {\bar{B}}^{'} l^{+} l^{-}$ decays are also discussed.
Cited by 2
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Cited by 9
- 16 August 2022
- Published by American Physical Society (APS) in Physical Review D
Two-body baryonic $B_{u, d, s}$ and $B_{c}$ to charmless final state decays
by Chun-Khiang Chua
We study the rates and direct $C P$ violations of two-body baryonic ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ and $B_{c}^{-} \to {B \bar{B}}^{'}$ decays, where the final state baryons include low-lying octet and decuplet baryons. We incorporate topological amplitude formalism and the factorization approach. Asymptotic relations at large $m_{b}$ are used to simplify decay amplitudes. Using the most up-to-date data on ${\bar{B}}^{0} \to p \bar{p}$ and $B^{-} \to Λ \bar{p}$ decay rates as inputs, rates and direct $C P$ violations of ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ decays are revised and predicted. It is interesting that the results on rates satisfy all existing experimental bounds and some are close to the bounds. Factorization diagrams contribute to penguin-exchange, exchange, annihilation, and penguin-annihilation amplitudes. Although the resulting penguin-exchange factorization amplitudes are sizable, the rest suffer from severe chiral suppression and are sensitive to nonfactorizable contributions. As the ${\bar{B}}_{s} \to p \bar{p}$ decay is governed by exchange and penguin annihilation amplitudes, the rate predicted in factorization calculation is very rare, but it can be enhanced by including nonfactorizable contributions. The case where the rate is enhanced to saturate the present experimental bound through the enhancement on exchange or penguin-annihilation amplitudes is discussed. As annihilation modes $B_{c}^{-} \to {B \bar{B}}^{'}$ decays from factorization calculation are found to be very rare, but they can be enhanced by including nonfactorizable contributions as well. Small direct $C P$ violations of pure penguin modes in $Δ S = - 1$ ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ decays are robust predictions of the SM, while vanishing direct $C P$ violations of exchange modes in ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ decays and in all $B_{c}^{-} \to {B \bar{B}}^{'}$ decay modes are null tests of the SM.
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- 16 August 2022
- Published by American Physical Society (APS) in Physical Review D
Open Access
Two-body baryonic $B_{u, d, s}$ and $B_{c}$ to charmless final state decays
by Chun-Khiang Chua
We study the rates and direct $C P$ violations of two-body baryonic ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ and $B_{c}^{-} \to {B \bar{B}}^{'}$ decays, where the final state baryons include low-lying octet and decuplet baryons. We incorporate topological amplitude formalism and the factorization approach. Asymptotic relations at large $m_{b}$ are used to simplify decay amplitudes. Using the most up-to-date data on ${\bar{B}}^{0} \to p \bar{p}$ and $B^{-} \to Λ \bar{p}$ decay rates as inputs, rates and direct $C P$ violations of ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ decays are revised and predicted. It is interesting that the results on rates satisfy all existing experimental bounds and some are close to the bounds. Factorization diagrams contribute to penguin-exchange, exchange, annihilation, and penguin-annihilation amplitudes. Although the resulting penguin-exchange factorization amplitudes are sizable, the rest suffer from severe chiral suppression and are sensitive to nonfactorizable contributions. As the ${\bar{B}}_{s} \to p \bar{p}$ decay is governed by exchange and penguin annihilation amplitudes, the rate predicted in factorization calculation is very rare, but it can be enhanced by including nonfactorizable contributions. The case where the rate is enhanced to saturate the present experimental bound through the enhancement on exchange or penguin-annihilation amplitudes is discussed. As annihilation modes $B_{c}^{-} \to {B \bar{B}}^{'}$ decays from factorization calculation are found to be very rare, but they can be enhanced by including nonfactorizable contributions as well. Small direct $C P$ violations of pure penguin modes in $Δ S = - 1$ ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ decays are robust predictions of the SM, while vanishing direct $C P$ violations of exchange modes in ${\bar{B}}_{u, d, s} \to {B \bar{B}}^{'}$ decays and in all $B_{c}^{-} \to {B \bar{B}}^{'}$ decay modes are null tests of the SM.
Cited by 9
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Cited by 43
- 26 February 2021
- Published by American Physical Society (APS) in Physical Review D
Finite-width effects in three-body $B$ decays
by Hai-Yang Cheng, Cheng-Wei Chiang, Chun-Khiang Chua
It is customary to apply the so-called narrow width approximation $Γ (B \to R P_{3} \to P_{1} P_{2} P_{3}) = Γ (B \to R P_{3}) B (R \to P_{1} P_{2})$ to extract the branching fraction of the quasi-two-body decay $B \to R P_{3}$ , with $R$ and $P_{3}$ being an intermediate resonant state and a pseudoscalar meson, respectively. However, the above factorization is valid only in the zero width limit. We consider a correction parameter $η_{R}$ from finite-width effects. Our main results are as follows: (i) We present a general framework for computing $η_{R}$ and show that it can be expressed in terms of the normalized differential rate and determined by its value at the resonance. (ii) We introduce a form factor $F (s_{12}, m_{R})$ for the strong coupling involved in the $R (m_{12}) \to P_{1} P_{2}$ decay when $m_{12}$ is away from $m_{R}$ . We find that off-shell effects are small in vector meson productions, but prominent in the $K_{2}^{*} (1430)$ , $σ / f_{0} (500)$ , and $K_{0}^{*} (1430)$ resonances. (iii) We evaluate $η_{R}$ in the theoretical framework of QCD factorization (QCDF) and in the experimental parametrization (EXPP) for three-body decay amplitudes. In general, $η_{R}^{QCDF}$ and $η_{R}^{EXPP}$ are similar for vector mesons, but different for tensor and scalar resonances. A study of the differential rates enables us to understand the origin of their differences. (iv) Finite-width corrections to $B (B^{-} \to R P)_{NWA}$ obtained in the narrow width approximation are generally small, less than 10%, but they are prominent in $B^{-} \to σ / f_{0} (500) π^{-}$ and $B^{-} \to {\bar{K}}_{0}^{* 0} (1430) π^{-}$ decays. The EXPP of the normalized differential rates should be contrasted with the theoretical predictions from QCDF calculation as the latter properly takes into account the energy dependence in weak decay amplitudes. (v) It is common to use the Gounaris-Sakurai model to describe the line shape of the broad $ρ (770)$ resonance. After including finite-width effects, the PDG value of $B (B^{-} \to ρ π^{-}) = (8.3 \pm 1.2) \times 10^{- 6}$ should be corrected to $(7.9 \pm 1.1) \times 10^{- 6}$ in EXPP and $(7.7 \pm 1.1) \times 10^{- 6}$ in QCDF. (vi) For the very broad $σ / f_{0} (500)$ scalar resonance, we use a simple pole model to describe its line shape and find a very large width effect: $η_{σ}^{QCDF} \sim 2.15$ and $η_{σ}^{EXPP} \sim 1.64$ . Consequently, $B^{-} \to σ π^{-}$ has a large branching fraction of order $10^{- 5}$ . (vii) We employ the Breit-Wigner line shape to describe the production of $K_{0}^{*} (1430)$ in three-body $B$ decays and find large off-shell effects. The smallness of $η_{K_{0}^{*}}^{QCDF}$ relative to $η_{K_{0}^{*}}^{EXPP}$ is ascribed to the differences in the normalized differential rates off the resonance. (viii) In the approach of QCDF, the calculated $C P$ asymmetries of $B^{-} \to f_{2} (1270) π^{-}, σ / f_{0} (500) π^{-}, K^{-} ρ^{0}$ decays agree with the experimental observations. The nonobservation of $C P$ asymmetry in $B^{-} \to ρ (770) π^{-}$ can also be accommodated in QCDF.
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- 26 February 2021
- Published by American Physical Society (APS) in Physical Review D
Open Access
Finite-width effects in three-body $B$ decays
by Hai-Yang Cheng, Cheng-Wei Chiang, Chun-Khiang Chua
It is customary to apply the so-called narrow width approximation $Γ (B \to R P_{3} \to P_{1} P_{2} P_{3}) = Γ (B \to R P_{3}) B (R \to P_{1} P_{2})$ to extract the branching fraction of the quasi-two-body decay $B \to R P_{3}$ , with $R$ and $P_{3}$ being an intermediate resonant state and a pseudoscalar meson, respectively. However, the above factorization is valid only in the zero width limit. We consider a correction parameter $η_{R}$ from finite-width effects. Our main results are as follows: (i) We present a general framework for computing $η_{R}$ and show that it can be expressed in terms of the normalized differential rate and determined by its value at the resonance. (ii) We introduce a form factor $F (s_{12}, m_{R})$ for the strong coupling involved in the $R (m_{12}) \to P_{1} P_{2}$ decay when $m_{12}$ is away from $m_{R}$ . We find that off-shell effects are small in vector meson productions, but prominent in the $K_{2}^{*} (1430)$ , $σ / f_{0} (500)$ , and $K_{0}^{*} (1430)$ resonances. (iii) We evaluate $η_{R}$ in the theoretical framework of QCD factorization (QCDF) and in the experimental parametrization (EXPP) for three-body decay amplitudes. In general, $η_{R}^{QCDF}$ and $η_{R}^{EXPP}$ are similar for vector mesons, but different for tensor and scalar resonances. A study of the differential rates enables us to understand the origin of their differences. (iv) Finite-width corrections to $B (B^{-} \to R P)_{NWA}$ obtained in the narrow width approximation are generally small, less than 10%, but they are prominent in $B^{-} \to σ / f_{0} (500) π^{-}$ and $B^{-} \to {\bar{K}}_{0}^{* 0} (1430) π^{-}$ decays. The EXPP of the normalized differential rates should be contrasted with the theoretical predictions from QCDF calculation as the latter properly takes into account the energy dependence in weak decay amplitudes. (v) It is common to use the Gounaris-Sakurai model to describe the line shape of the broad $ρ (770)$ resonance. After including finite-width effects, the PDG value of $B (B^{-} \to ρ π^{-}) = (8.3 \pm 1.2) \times 10^{- 6}$ should be corrected to $(7.9 \pm 1.1) \times 10^{- 6}$ in EXPP and $(7.7 \pm 1.1) \times 10^{- 6}$ in QCDF. (vi) For the very broad $σ / f_{0} (500)$ scalar resonance, we use a simple pole model to describe its line shape and find a very large width effect: $η_{σ}^{QCDF} \sim 2.15$ and $η_{σ}^{EXPP} \sim 1.64$ . Consequently, $B^{-} \to σ π^{-}$ has a large branching fraction of order $10^{- 5}$ . (vii) We employ the Breit-Wigner line shape to describe the production of $K_{0}^{*} (1430)$ in three-body $B$ decays and find large off-shell effects. The smallness of $η_{K_{0}^{*}}^{QCDF}$ relative to $η_{K_{0}^{*}}^{EXPP}$ is ascribed to the differences in the normalized differential rates off the resonance. (viii) In the approach of QCDF, the calculated $C P$ asymmetries of $B^{-} \to f_{2} (1270) π^{-}, σ / f_{0} (500) π^{-}, K^{-} ρ^{0}$ decays agree with the experimental observations. The nonobservation of $C P$ asymmetry in $B^{-} \to ρ (770) π^{-}$ can also be accommodated in QCDF.
Cited by 43
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- 28 December 2020
- Published by arXiv in arXiv
Width effects in resonant three-body decays: $B$ decay as an example
by Hai-Yang Cheng, Cheng-Wei Chiang, Chun-Khiang Chua
For three-body hadron decays mediated by intermediate resonances with large widths, we show how to properly extract the quasi-two-body decay rates for a meaningful comparison with the corresponding theoretical estimates, using several $B$ decays as explicit examples. We compute the correction factor from finite width effects in the QCD factorization approach, and make a comparison with that using the experimental parameterization in which the momentum dependence in the weak dynamics is absent. Although the difference is generally less than $10\%$ for tensor and vector resonances, it can be as large as $(25-40)\%$ for scalar resonances. Our finding can in fact be applied to general quasi-two-body decays.
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- 28 December 2020
- Published by arXiv in arXiv
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Width effects in resonant three-body decays: $B$ decay as an example
by Hai-Yang Cheng, Cheng-Wei Chiang, Chun-Khiang Chua
For three-body hadron decays mediated by intermediate resonances with large widths, we show how to properly extract the quasi-two-body decay rates for a meaningful comparison with the corresponding theoretical estimates, using several $B$ decays as explicit examples. We compute the correction factor from finite width effects in the QCD factorization approach, and make a comparison with that using the experimental parameterization in which the momentum dependence in the weak dynamics is absent. Although the difference is generally less than $10\%$ for tensor and vector resonances, it can be as large as $(25-40)\%$ for scalar resonances. Our finding can in fact be applied to general quasi-two-body decays.
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Cited by 22
- 30 September 2020
- Published by American Physical Society (APS) in Physical Review D
Data-driven study of the implications of anomalous magnetic moments and lepton flavor violating processes of $e$ , $μ$ , and $τ$
by Chun-Khiang Chua
We study anomalous magnetic moments and flavor violating processes of $e$ , $μ$ , and $τ$ leptons. We use a data driven approach to investigate the implications of the present data on the parameters of a class of models, which has spin-0 scalar and spin- $1 / 2$ fermion fields. We compare two different cases, which has or does not have a built-in cancelation mechanism. Our findings are as following. Chiral interactions are unable to generate large enough $Δ a_{e}$ and $Δ a_{μ}$ to accommodate the experimental results. Although sizable $Δ a_{e}$ and $Δ a_{μ}$ can be generated from nonchiral interactions, they are not contributed from the same source. Presently, the upper limit of $μ \to e γ$ decay gives the most severe constraints on photonic penguin contributions in $μ \to e$ transitions, but the situation may change in considering future experimental sensitivities. The $Z$ -penguin diagrams can constrain chiral interaction better than photonic penguin diagrams in $μ \to e$ transitions. In most of the parameter space, box contributions to $μ \to 3 e$ decay are subleading. The present bounds on $Δ a_{τ}$ and $d_{τ}$ are unable to give useful constraints on parameters. In $τ \to e$ ( $μ$ ) transitions, the present $τ \to e γ (μ γ)$ upper limit constrains the photonic penguin contribution better than the $τ \to 3 e$ $(3 μ)$ upper limit, and $Z$ -penguin amplitudes constrain chiral interaction better than photonic penguin amplitudes. Box contributions to $τ \to 3 e$ and $τ \to 3 μ$ decays can sometime be comparable to $Z$ -penguin contributions. The $τ^{-} \to e^{-} μ^{+} e^{-}$ and $τ^{-} \to μ^{-} e^{+} μ^{-}$ rates are highly constrained by $τ \to e γ$ , $μ \to e γ$ and $τ \to μ γ$ , $μ \to e γ$ upper limits, respectively. We compare the current experimental upper limits, future sensitivities and bounds from consistency on various muon and tau LFV processes.
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- 30 September 2020
- Published by American Physical Society (APS) in Physical Review D
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Data-driven study of the implications of anomalous magnetic moments and lepton flavor violating processes of $e$ , $μ$ , and $τ$
by Chun-Khiang Chua
We study anomalous magnetic moments and flavor violating processes of $e$ , $μ$ , and $τ$ leptons. We use a data driven approach to investigate the implications of the present data on the parameters of a class of models, which has spin-0 scalar and spin- $1 / 2$ fermion fields. We compare two different cases, which has or does not have a built-in cancelation mechanism. Our findings are as following. Chiral interactions are unable to generate large enough $Δ a_{e}$ and $Δ a_{μ}$ to accommodate the experimental results. Although sizable $Δ a_{e}$ and $Δ a_{μ}$ can be generated from nonchiral interactions, they are not contributed from the same source. Presently, the upper limit of $μ \to e γ$ decay gives the most severe constraints on photonic penguin contributions in $μ \to e$ transitions, but the situation may change in considering future experimental sensitivities. The $Z$ -penguin diagrams can constrain chiral interaction better than photonic penguin diagrams in $μ \to e$ transitions. In most of the parameter space, box contributions to $μ \to 3 e$ decay are subleading. The present bounds on $Δ a_{τ}$ and $d_{τ}$ are unable to give useful constraints on parameters. In $τ \to e$ ( $μ$ ) transitions, the present $τ \to e γ (μ γ)$ upper limit constrains the photonic penguin contribution better than the $τ \to 3 e$ $(3 μ)$ upper limit, and $Z$ -penguin amplitudes constrain chiral interaction better than photonic penguin amplitudes. Box contributions to $τ \to 3 e$ and $τ \to 3 μ$ decays can sometime be comparable to $Z$ -penguin contributions. The $τ^{-} \to e^{-} μ^{+} e^{-}$ and $τ^{-} \to μ^{-} e^{+} μ^{-}$ rates are highly constrained by $τ \to e γ$ , $μ \to e γ$ and $τ \to μ γ$ , $μ \to e γ$ upper limits, respectively. We compare the current experimental upper limits, future sensitivities and bounds from consistency on various muon and tau LFV processes.
Cited by 22
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Cited by 36
- 15 September 2020
- Published by American Physical Society (APS) in Physical Review D
Branching fractions and $C P$ violation in $B^{-} \to K^{+} K^{-} π^{-}$ and $B^{-} \to π^{+} π^{-} π^{-}$ decays
by Hai-Yang Cheng, Chun-Khiang Chua
We present in this work a study of tree-dominated charmless three-body decays of $B$ mesons, $B^{-} \to K^{+} K^{-} π^{-}$ and $B^{-} \to π^{+} π^{-} π^{-}$ , within the factorization approach. The main results are: (i) There are two distinct sources of nonresonant contributions: one arises from the $b \to u$ tree transition and the other from the nonresonant matrix element of scalar densities $⟨ M_{1} M_{2} | {\bar{q}}_{1} q_{2} | 0 ⟩^{NR}$ . It turns out that even for tree-dominated three-body decays, dominant nonresonant contributions originate from the penguin diagram rather than from the $b \to u$ tree process, as implied by the large nonresonant component observed recently in the $π^{-} K^{+}$ system which accounts for one third of the $B^{-} \to K^{+} K^{-} π^{-}$ rate. (ii) The calculated branching fraction of $B^{-} \to f_{2} (1270) π^{-} \to K^{+} K^{-} π^{-}$ is smaller than the LHCb by a factor of $\sim 7$ in its central value, but the predicted $B (B^{-} \to f_{2} (1270) π^{-} \to π^{+} π^{-} π^{-})$ is consistent with the data. Branching fractions of $B^{-} \to f_{2} (1270) π^{-}$ extracted from the LHCb measurements of these two processes also differ by a factor of seven! Therefore, it is likely that the $f_{2} (1270)$ contribution to $B^{-} \to K^{+} K^{-} π^{-}$ is largely overestimated experimentally. Including $1 / m_{b}$ power corrections from penguin annihilation inferred from QCD factorization (QCDF), a sizable $C P$ asymmetry of 25% in the $f_{2} (1270)$ component agrees with experiment. (iii) A fraction of 5% for the $ρ (1450)$ component in $B^{-} \to π^{+} π^{-} π^{-}$ is in accordance with the theoretical expectation. However, a large fraction of 30% in $B^{-} \to K^{+} K^{-} π^{-}$ is entirely unexpected. This issue needs to be clarified in the future. (iv) We study final-state $π π \leftrightarrow K \bar{K}$ rescattering and find that the rescattering contributions to both $B^{-} \to K^{+} K^{-} π^{-}$ and $B^{-} \to π^{+} π^{-} π^{-}$ seem to be overestimated experimentally by a factor 4. (v) Using the QCDF expression for the $B^{-} \to σ / f_{0} (500) π^{-}$ amplitude to study the decay $B^{-} \to σ π^{-} \to π^{+} π^{-} π^{-}$ , the resultant branching fraction and $C P$ violation of 15% agree with experiment. (vi) $C P$ asymmetry for the dominant quasi-two-body decay mode $B^{-} \to ρ^{0} π^{-}$ was found by the LHCb to be consistent with zero in all three $S$ -wave models. In the QCDF approach, $1 / m_{b}$ power corrections, namely, penguin annihilation and hard spectator interactions contribute destructively to $A_{C P} (B^{-} \to ρ^{0} π^{-})$ to render it consistent with zero. (vii) A significant $C P$ asymmetry has been seen in the $ρ^{0} (770)$ region for positive- and negative-helicity angle cosines. Considering the low $π^{+} π^{-}$ invariant mass region of the $B^{+} \to π^{+} π^{+} π^{-}$ Dalitz plot of $C P$ asymmetries divided into four zones, the pattern of $C P$ violation in each zone is well described by the interference between $ρ (770)$ and $σ (500)$ as well as the nonresonant background.
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- 15 September 2020
- Published by American Physical Society (APS) in Physical Review D
Open Access
Branching fractions and $C P$ violation in $B^{-} \to K^{+} K^{-} π^{-}$ and $B^{-} \to π^{+} π^{-} π^{-}$ decays
by Hai-Yang Cheng, Chun-Khiang Chua
We present in this work a study of tree-dominated charmless three-body decays of $B$ mesons, $B^{-} \to K^{+} K^{-} π^{-}$ and $B^{-} \to π^{+} π^{-} π^{-}$ , within the factorization approach. The main results are: (i) There are two distinct sources of nonresonant contributions: one arises from the $b \to u$ tree transition and the other from the nonresonant matrix element of scalar densities $⟨ M_{1} M_{2} | {\bar{q}}_{1} q_{2} | 0 ⟩^{NR}$ . It turns out that even for tree-dominated three-body decays, dominant nonresonant contributions originate from the penguin diagram rather than from the $b \to u$ tree process, as implied by the large nonresonant component observed recently in the $π^{-} K^{+}$ system which accounts for one third of the $B^{-} \to K^{+} K^{-} π^{-}$ rate. (ii) The calculated branching fraction of $B^{-} \to f_{2} (1270) π^{-} \to K^{+} K^{-} π^{-}$ is smaller than the LHCb by a factor of $\sim 7$ in its central value, but the predicted $B (B^{-} \to f_{2} (1270) π^{-} \to π^{+} π^{-} π^{-})$ is consistent with the data. Branching fractions of $B^{-} \to f_{2} (1270) π^{-}$ extracted from the LHCb measurements of these two processes also differ by a factor of seven! Therefore, it is likely that the $f_{2} (1270)$ contribution to $B^{-} \to K^{+} K^{-} π^{-}$ is largely overestimated experimentally. Including $1 / m_{b}$ power corrections from penguin annihilation inferred from QCD factorization (QCDF), a sizable $C P$ asymmetry of 25% in the $f_{2} (1270)$ component agrees with experiment. (iii) A fraction of 5% for the $ρ (1450)$ component in $B^{-} \to π^{+} π^{-} π^{-}$ is in accordance with the theoretical expectation. However, a large fraction of 30% in $B^{-} \to K^{+} K^{-} π^{-}$ is entirely unexpected. This issue needs to be clarified in the future. (iv) We study final-state $π π \leftrightarrow K \bar{K}$ rescattering and find that the rescattering contributions to both $B^{-} \to K^{+} K^{-} π^{-}$ and $B^{-} \to π^{+} π^{-} π^{-}$ seem to be overestimated experimentally by a factor 4. (v) Using the QCDF expression for the $B^{-} \to σ / f_{0} (500) π^{-}$ amplitude to study the decay $B^{-} \to σ π^{-} \to π^{+} π^{-} π^{-}$ , the resultant branching fraction and $C P$ violation of 15% agree with experiment. (vi) $C P$ asymmetry for the dominant quasi-two-body decay mode $B^{-} \to ρ^{0} π^{-}$ was found by the LHCb to be consistent with zero in all three $S$ -wave models. In the QCDF approach, $1 / m_{b}$ power corrections, namely, penguin annihilation and hard spectator interactions contribute destructively to $A_{C P} (B^{-} \to ρ^{0} π^{-})$ to render it consistent with zero. (vii) A significant $C P$ asymmetry has been seen in the $ρ^{0} (770)$ region for positive- and negative-helicity angle cosines. Considering the low $π^{+} π^{-}$ invariant mass region of the $B^{+} \to π^{+} π^{+} π^{-}$ Dalitz plot of $C P$ asymmetries divided into four zones, the pattern of $C P$ violation in each zone is well described by the interference between $ρ (770)$ and $σ (500)$ as well as the nonresonant background.
Cited by 36
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Cited by 3
- 10 June 2020
- Published by Sissa Medialab Srl
Color-allowed Bottom Baryon to $s$-wave and $p$-wave Charmed Baryon non-leptonic Decays
by Chun-Khiang Chua
We study color allowed bottom baryon to $s$-wave and $p$-wave charmed baryon non-leptonic decays in this work. The charmed baryons include spin-1/2 and spin-3/2 states. Explicitly, we consider $\Lambda_b\to \Lambda^{(*,**)}_c M^-$, $\Xi_b\to\Xi_c^{(**)} M^-$ and $\Omega_b\to\Omega^{(*,**)}_c M^-$ decays with $M=\pi, K, \rho, K^*, a_1, D, D_s, D^*, D^*_s$, $\Lambda^{(*,**)}_c$ $=\Lambda_c$, $\Lambda_c(2595)$, $\Lambda_c(2625)$, $\Lambda_c(2765)$, $\Lambda_c(2940)$, $\Xi_c^{(**)}=$ $\Xi_c$, $\Xi_c(2790)$, $\Xi_c(2815)$ and $\Omega^{(*,**)}_c=$ $\Omega_c$, $\Omega_c(2770)$, $\Omega_c(3050)$, $\Omega_c(3090)$, $\Omega_c(3120)$. There are six types of transitions, namely, (i) ${\cal B}_b({\bf \bar 3_f},1/2^+)$ to ${\cal B}_c({\bf \bar 3_f},1/2^+)$, (ii) ${\cal B}_b({\bf 6_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},1/2^+)$, (iii) ${\cal B}_b({\bf 6_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},3/2^+)$, (iv) ${\cal B}_b({\bf 6_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},3/2^-)$, (v) ${\cal B}_b({\bf \bar 3_f},1/2^+)$ to ${\cal B}_c({\bf \bar 3_f},1/2^-)$, and (vi) ${\cal B}_b(\bar {\bf 3_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},3/2^-)$ transitions. Types (i) to (iii) involve spin 1/2 and 3/2 $s$-wave charmed baryons, while types (iv) to (vi) involve spin 1/2 and 3/2 $p$-wave charmed baryons. The light diquarks are spectating in these transitions. The transition form factors are calculated in the light-front quark model approach. All of the form factors in the $1/2\to 1/2$ and $1/2 \to 3/2$ transitions are extracted, and they are found to reasonably satisfy the relations obtained in the heavy quark limit, as we are using heavy but finite $m_b$ and $m_c$. Using na\"{i}ve factorization, decay rates and up-down asymmetries of the above modes are predicted and can be checked experimentally. The study on these decay modes may shed light on the quantum numbers of $\Lambda_c(2765)$, $\Lambda_c(2940)$, $\Omega_c(3050)$, $\Omega_c(3090)$ and $\Omega_c(3120)$.
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- 10 June 2020
- Published by Sissa Medialab Srl
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Color-allowed Bottom Baryon to $s$-wave and $p$-wave Charmed Baryon non-leptonic Decays
by Chun-Khiang Chua
We study color allowed bottom baryon to $s$-wave and $p$-wave charmed baryon non-leptonic decays in this work. The charmed baryons include spin-1/2 and spin-3/2 states. Explicitly, we consider $\Lambda_b\to \Lambda^{(*,**)}_c M^-$, $\Xi_b\to\Xi_c^{(**)} M^-$ and $\Omega_b\to\Omega^{(*,**)}_c M^-$ decays with $M=\pi, K, \rho, K^*, a_1, D, D_s, D^*, D^*_s$, $\Lambda^{(*,**)}_c$ $=\Lambda_c$, $\Lambda_c(2595)$, $\Lambda_c(2625)$, $\Lambda_c(2765)$, $\Lambda_c(2940)$, $\Xi_c^{(**)}=$ $\Xi_c$, $\Xi_c(2790)$, $\Xi_c(2815)$ and $\Omega^{(*,**)}_c=$ $\Omega_c$, $\Omega_c(2770)$, $\Omega_c(3050)$, $\Omega_c(3090)$, $\Omega_c(3120)$. There are six types of transitions, namely, (i) ${\cal B}_b({\bf \bar 3_f},1/2^+)$ to ${\cal B}_c({\bf \bar 3_f},1/2^+)$, (ii) ${\cal B}_b({\bf 6_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},1/2^+)$, (iii) ${\cal B}_b({\bf 6_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},3/2^+)$, (iv) ${\cal B}_b({\bf 6_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},3/2^-)$, (v) ${\cal B}_b({\bf \bar 3_f},1/2^+)$ to ${\cal B}_c({\bf \bar 3_f},1/2^-)$, and (vi) ${\cal B}_b(\bar {\bf 3_f},1/2^+)$ to ${\cal B}_c({\bf 6_f},3/2^-)$ transitions. Types (i) to (iii) involve spin 1/2 and 3/2 $s$-wave charmed baryons, while types (iv) to (vi) involve spin 1/2 and 3/2 $p$-wave charmed baryons. The light diquarks are spectating in these transitions. The transition form factors are calculated in the light-front quark model approach. All of the form factors in the $1/2\to 1/2$ and $1/2 \to 3/2$ transitions are extracted, and they are found to reasonably satisfy the relations obtained in the heavy quark limit, as we are using heavy but finite $m_b$ and $m_c$. Using na\"{i}ve factorization, decay rates and up-down asymmetries of the above modes are predicted and can be checked experimentally. The study on these decay modes may shed light on the quantum numbers of $\Lambda_c(2765)$, $\Lambda_c(2940)$, $\Omega_c(3050)$, $\Omega_c(3090)$ and $\Omega_c(3120)$.
Cited by 3
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Cited by 47
- 26 August 2019
- Published by American Physical Society (APS) in Physical Review D
Color-allowed bottom baryon to $s$ -wave and $p$ -wave charmed baryon nonleptonic decays
by Chun-Khiang Chua
We study color allowed bottom baryon to $s$ -wave and $p$ -wave charmed baryon nonleptonic decays in this work. The charmed baryons include $spin − 1 / 2$ and $spin − 3 / 2$ states. Explicitly, we consider $Λ_{b} \to Λ_{c}^{(*, * *)} M^{-}$ , $Ξ_{b} \to Ξ_{c}^{(* *)} M^{-}$ , and $Ω_{b} \to Ω_{c}^{(*, * *)} M^{-}$ decays with $M = π, K, ρ, K^{*}, a_{1}, D, D_{s}, D^{*}, D_{s}^{*}$ , $Λ_{c}^{(*, * *)} = Λ_{c}, Λ_{c} (2595), Λ_{c} (2625), Λ_{c} (2765), Λ_{c} (2940)$ , $Ξ_{c}^{(* *)} = Ξ_{c}, Ξ_{c} (2790), Ξ_{c} (2815)$ and $Ω_{c}^{(*, * *)} = Ω_{c}, Ω_{c} (2770), Ω_{c} (3050), Ω_{c} (3090), Ω_{c} (3120)$ . There are six types of transitions, namely, (i) $B_{b} ({\bar{3}}_{f}, 1 / 2^{+})$ to $B_{c} ({\bar{3}}_{f}, 1 / 2^{+})$ , (ii) $B_{b} (6_{f}, 1 / 2^{+})$ to $B_{c} (6_{f}, 1 / 2^{+})$ , (iii) $B_{b} (6_{f}, 1 / 2^{+})$ to $B_{c} (6_{f}, 3 / 2^{+})$ , (iv) $B_{b} (6_{f}, 1 / 2^{+})$ to $B_{c} (6_{f}, 3 / 2^{-})$ , (v) $B_{b} ({\bar{3}}_{f}, 1 / 2^{+})$ to $B_{c} ({\bar{3}}_{f}, 1 / 2^{-})$ , and (vi) $B_{b} (\bar{3_{f}}, 1 / 2^{+})$ to $B_{c} ({\bar{3}}_{f}, 3 / 2^{-})$ transitions. Types (i) to (iii) involve spin $1 / 2$ and $3 / 2$ $s$ -wave charmed baryons, while types (iv) to (vi) involve spin $1 / 2$ and $3 / 2$ $p$ -wave charmed baryons. The light diquarks are spectating in these transitions. The transition form factors are calculated in the light-front quark model approach. All of the form factors in the $1 / 2 \to 1 / 2$ and $1 / 2 \to 3 / 2$ transitions are extracted, and they are found to reasonably satisfy the relations obtained in the heavy quark limit, as we are using heavy but finite $m_{b}$ and $m_{c}$ . Using naïve factorization, decay rates and up-down asymmetries of the above modes are predicted and can be checked experimentally. We compare our results to data and other theoretical predictions. The study on these decay modes may shed light on the quantum numbers of $Λ_{c} (2765)$ , $Λ_{c} (2940) Ω_{c} (3050)$ , $Ω_{c} (3090)$ , and $Ω_{c} (3120)$ .
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- 26 August 2019
- Published by American Physical Society (APS) in Physical Review D
Open Access
Color-allowed bottom baryon to $s$ -wave and $p$ -wave charmed baryon nonleptonic decays
by Chun-Khiang Chua
We study color allowed bottom baryon to $s$ -wave and $p$ -wave charmed baryon nonleptonic decays in this work. The charmed baryons include $spin − 1 / 2$ and $spin − 3 / 2$ states. Explicitly, we consider $Λ_{b} \to Λ_{c}^{(*, * *)} M^{-}$ , $Ξ_{b} \to Ξ_{c}^{(* *)} M^{-}$ , and $Ω_{b} \to Ω_{c}^{(*, * *)} M^{-}$ decays with $M = π, K, ρ, K^{*}, a_{1}, D, D_{s}, D^{*}, D_{s}^{*}$ , $Λ_{c}^{(*, * *)} = Λ_{c}, Λ_{c} (2595), Λ_{c} (2625), Λ_{c} (2765), Λ_{c} (2940)$ , $Ξ_{c}^{(* *)} = Ξ_{c}, Ξ_{c} (2790), Ξ_{c} (2815)$ and $Ω_{c}^{(*, * *)} = Ω_{c}, Ω_{c} (2770), Ω_{c} (3050), Ω_{c} (3090), Ω_{c} (3120)$ . There are six types of transitions, namely, (i) $B_{b} ({\bar{3}}_{f}, 1 / 2^{+})$ to $B_{c} ({\bar{3}}_{f}, 1 / 2^{+})$ , (ii) $B_{b} (6_{f}, 1 / 2^{+})$ to $B_{c} (6_{f}, 1 / 2^{+})$ , (iii) $B_{b} (6_{f}, 1 / 2^{+})$ to $B_{c} (6_{f}, 3 / 2^{+})$ , (iv) $B_{b} (6_{f}, 1 / 2^{+})$ to $B_{c} (6_{f}, 3 / 2^{-})$ , (v) $B_{b} ({\bar{3}}_{f}, 1 / 2^{+})$ to $B_{c} ({\bar{3}}_{f}, 1 / 2^{-})$ , and (vi) $B_{b} (\bar{3_{f}}, 1 / 2^{+})$ to $B_{c} ({\bar{3}}_{f}, 3 / 2^{-})$ transitions. Types (i) to (iii) involve spin $1 / 2$ and $3 / 2$ $s$ -wave charmed baryons, while types (iv) to (vi) involve spin $1 / 2$ and $3 / 2$ $p$ -wave charmed baryons. The light diquarks are spectating in these transitions. The transition form factors are calculated in the light-front quark model approach. All of the form factors in the $1 / 2 \to 1 / 2$ and $1 / 2 \to 3 / 2$ transitions are extracted, and they are found to reasonably satisfy the relations obtained in the heavy quark limit, as we are using heavy but finite $m_{b}$ and $m_{c}$ . Using naïve factorization, decay rates and up-down asymmetries of the above modes are predicted and can be checked experimentally. We compare our results to data and other theoretical predictions. The study on these decay modes may shed light on the quantum numbers of $Λ_{c} (2765)$ , $Λ_{c} (2940) Ω_{c} (3050)$ , $Ω_{c} (3090)$ , and $Ω_{c} (3120)$ .
Cited by 47

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