${\Lambda }_b\to p$ transition form factors in perturbative QCD

Abstract

We reanalyze the ${\Lambda }_b\to p$ transition form factors in the perturbative QCD (PQCD) approach by including higher-twist light-cone distribution amplitudes (LCDAs) of a ${\Lambda }_b$ baryon and a proton. The previous PQCD evaluation performed decades ago with only the leading-twist ${\Lambda }_b$ baryon and proton LCDAs gave the form factors, which are two orders of magnitude smaller than indicated by experimental data. We find that the twist-4 ${\Lambda }_b$ baryon LCDAs and the twist-4 and -5 proton LCDAs contribute dominantly, and the enhanced form factors become consistent with those from lattice QCD and other nonperturbative methods. The estimated branching ratios of the semileptonic decays ${\Lambda }_b\to p\ell {\bar{\nu }}_{\ell }$ and the hadronic decay ${\Lambda }_b\to p\pi$ are also close to the data. It implies that the $b$ quark mass is not really heavy enough, and higher-power contributions play a crucial role, similar to the observation made in analyses of $B$ meson transition form factors. With the formalism established in this work, we are ready to study various exclusive heavy baryon decays systematically in the PQCD approach.

arXiv comment37 pages, 7 figures, version to be published in Eur.Phys.J.C

References in corpus (62)

• An effective field theory for collinear and soft gluons: heavy to light decays
• Soft-Collinear Factorization in Effective Field Theory
• QCD Factorization for $B\to \pi \pi$ Decays: Strong Phases and CP Violation in the Heavy Quark Limit
• QCD factorization for exclusive, non-leptonic B meson decays: General arguments and the case of heavy-light final states
• QCD factorization for B->PP and B->PV decays
• QCD Factorization in B -> pi K, pi pi Decays and Extraction of Wolfenstein Parameters
• Penguin Enhancement and $B\to K\pi$ decays in perturbative QCD
• Fat penguins and imaginary penguins in perturbative QCD
• Branching Ratio and CP Violation of B to pi pi Decays in Perturbative QCD Approach
• Final State Interactions in Hadronic B Decays
• Leading-power contributions to $B\to \pi ,\rho$ transition form factors
• ${\Lambda }_b\to p{\ell }^{-}{\bar{\nu }}_{\ell }$ and ${\Lambda }_b\to {\Lambda }_c{\ell }^{-}{\bar{\nu }}_{\ell }$ form factors from lattice QCD with relativistic heavy quarks
• Extraction of $V_{ub}$ from the Decay $B\to \pi l\nu$
• Branching ratios and direct CP asymmetries in $D\to PP$ decays
• Determination of the quark coupling strength $|V_{ub}|$ using baryonic decays
• B to light meson transition form factors calculated in perturbative QCD approach
• Higher Twist Distribution Amplitudes of the Nucleon in QCD
• Perturbative QCD Analysis of $B$ Meson Decays
• Threshold resummation for exclusive B meson decays
• Discovery Potentials of Doubly Charmed Baryons
• Two-body hadronic charmed meson decays
• Weak Decays of Doubly Heavy Baryons: the $1/2\to 1/2$ case
• Form Factors and Strong Couplings of Heavy Baryons from QCD Light-Cone Sum Rules
• Light-Cone Distribution Amplitudes for Heavy-Quark Hadrons
• Measurement of matter-antimatter differences in beauty baryon decays
• Next-to-leading-order corrections to $B\to \pi$ form factors in $k_T$ factorization
• Perturbative Corrections to ${\Lambda }_b\to \Lambda$ Form Factors from QCD Light-Cone Sum Rules
• Updating B --> PP, VP decays in the framework of flavor symmetry
• ${\Lambda }_b\to {\Lambda }_c\tau {\bar{\nu }}_{\tau }$ Decay in the Standard Model and with New Physics
• Anatomy of the pQCD Approach to the Baryonic Decays ${\Lambda }_b\to p\pi ,pK$
• Predictions for nonleptonic Lambda_b and Theta_b decays
• Semileptonic decays of ${\Lambda }_b$ baryons in the relativistic quark model
• ${\Lambda }_b\to p,\Lambda$ transition form factors from QCD light-cone sum rules
• ${\Lambda }_b\to ({\Lambda }_c,p)\tau \nu$ decays within standard model and beyond
• Distribution Amplitudes of the Lambda_b Baryon in QCD
• QCD Sum Rules for Heavy Baryons at Next-to-Leading Order in alpha_s
• Direct CP violation in ${\Lambda }_b$ decays
• A Critical Analysis of the Proton Form Factor with Sudakov Suppression and Intrinsic Transverse Momentum
• PQCD Calculation for ${\Lambda }_b\to \Lambda \gamma$ in the Standard Model
• Λ_b \to ΛJ/ψdecay in perturbative QCD
• Factorization of Heavy-to-Light Baryonic Transitions in SCET
• Light-cone QCD sum rules for the semileptonic decay Lambda_b --> p lepton anti-neutrino
• Flavor SU(3) Topological Diagram and Irreducible Representation Amplitudes for Heavy Meson Charmless Hadronic Decays: Mismatch and Equivalence
• First Lattice QCD determination of semileptonic decays of charmed-strange baryons ${\Xi }_c$
• Resummation of rapidity logarithms in $B$ meson wave functions
• Revisiting semileptonic decays of ${\Lambda }_{b(c)}$ supported by baryon spectroscopy
• An Analysis of Diagonal and Non-diagonal QCD Sum Rules for Heavy Baryons at Next-to-Leading Order in α_S
• Rescattering mechanism of weak decays of double-charm baryons
• Decay ${\Lambda }_b\to pl\bar{\nu }$ in QCD sum rules
• Applicability of perturbative QCD to ${\Lambda }_b\to {\Lambda }_c$ decays
• Diquarks and the Semi-Leptonic Decay of ${\Lambda }_b$ in the Hybrid Scheme
• Endpoint Relations for Baryons
• Charmless two-body anti-triplet $b$-baryon decays
• The ${\Lambda }_b\to pl\bar{\nu }$ decay in perturbative QCD
• Charmless two body hadronic decays of ${\Lambda }_b$ baryon
• The perturbative proton form factor reexamined
• Next-to-leading-logarithm $k_T$ resummation for $B_c\to J/\psi$ decays
• The decay of ${\Lambda }_b\to p{K}^{-}$ in QCD factorization approach
• Non-leptonic two-body decays of ${\Lambda }_b^0$ in light-front quark model
• Predictions of Angular Observables for ${\bar{B}}_s\to K^{\ast }\ell \ell$ and $\bar{B}\to \rho \ell \ell$ in Standard Model
• Study of the ${\Lambda }_b\to N^{\ast }{\ell }^{+}{\ell }^{-}$ decay in light cone sum rules
• Next-to-Leading-logarithm threshold resummation for exclusive $B$ meson decays

Cited by in corpus (14)

• Light-cone distribution amplitudes of a light baryon in large-momentum effective theory
• Lightcone and quasi distribution amplitudes for light octet and decuplet baryons
• CP Violation of Baryon Decays with $N\pi$ Scatterings
• Estimates of exchange topological contributions and $CP$-violating observables in ${\Lambda }_b\to \Lambda \varphi$ decay
• Baryons in the light-front approach: The three-quark picture
• Observation of $D^{+}\to K_S^0{a}_0(980{)}^{+}$ in the amplitude analysis of $D^{+}\to K_S^0{\pi }^{+}\eta$
• Light Cone Distribution Amplitude for the $\Lambda$ Baryon from Lattice QCD
• Charmonium decays of beauty baryons in the perturbative QCD approach
• Higher twist corrections to doubly-charmed baryonic $B$ decays
• Final-state rescattering mechanism in bottom-baryon decays
• Mixing effects of $\eta -{\eta }^{\prime }$ in ${\Lambda }_b\to \Lambda {\eta }^{{(}^{\prime })}$ decays
• Form factors of ${\Lambda }_b^0\to {\Lambda }_c(2595{)}^{+}$ within light-cone QCD sum rules
• Estimates of the isospin-violating ${\Lambda }_b\to {\Sigma }^0\varphi ,{\Sigma }^{0}J/\psi$ decays and the $\Sigma -\Lambda$ mixing
• $U$-spin sum rules for two-body decays of bottom baryons