Angular Analysis of \boldmath ${\Lambda }_b\to {\Lambda }_c(\to \Lambda \pi )\ell \bar{\nu }$

Abstract

We revisit the decay ${\Lambda }_b^0\to {\Lambda }_c^{+}{\ell }^{-}\bar{\nu }$ ($\ell =e,\mu ,\tau$) with a subsequent two-body decay ${\Lambda }_c^{+}\to {\Lambda }^0{\pi }^{+}$ in the Standard Model and in generic New Physics models. The decay's joint four-differential angular distribution can be expressed in terms of ten angular observables, assuming negligible polarization of the initial ${\Lambda }_b$ state. We present compact analytical results for all angular observables, which enables us to discuss their possible New Physics reach. We find that the decay at hand probes more and complementary independent combinations of Wilson coefficients compared to its mesonic counter parts $\bar{B}\to D^{(\ast )}{\ell }^{-}\bar{\nu }$. Our result for the angular distribution is at variance with some of the results on scalar-vector interference terms in the literature. We provide numerical estimates for all angular observables based on lattice-QCD results for the ${\Lambda }_b\to {\Lambda }_c$ form factors and account for a recent measurement of the parity-violating parameter in ${\Lambda }_c^{+}\to {\Lambda }^0{\pi }^{+}$ decays by BESIII. A numerical implementation of our results is made publicly available as part of the EOS software.

arXiv comment15 pages, 1 table, 1 figure

References in corpus (28)

• On the B to D* tau nu Sensitivity to New Physics
• $B\to Dl\nu$ Form Factors at Non-Zero Recoil and Extraction of $|V_{cb}|$
• Revisiting $B\to D\ell \nu$
• $R(D^{\ast })$, $|V_{cb}|$, and the Heavy Quark Symmetry relations between 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
• $B\to P$ and $B\to V$ Form Factors from $B$-Meson Light-Cone Sum Rules beyond Leading Twist
• Determination of the quark coupling strength $|V_{ub}|$ using baryonic decays
• A fresh look at the determination of |V_cb| from B-> D^* l nu
• The $V_{cb}$ puzzle: an update
• Global fit to $b\to c\tau \nu$ transitions
• Impact of polarization observables and $B_c\to \tau \nu$ on new physics explanations of the $b\to c\tau \nu$ anomaly
• Phenomenology of ${\Lambda }_b\to {\Lambda }_c\tau {\bar{\nu }}_{\tau }$ using lattice QCD calculations
• $B\to D^{(\ast )}$ Form Factors from QCD Light-Cone Sum Rules
• ${\Lambda }_c\to \Lambda {\ell }^{+}{\nu }_{\ell }$ form factors and decay rates from lattice QCD with physical quark masses
• Angular Analysis of the Decay ${\Lambda }_b\to \Lambda (\to N\pi ){\ell }^{+}{\ell }^{-}$
• Perturbative corrections to $B\to D$ form factors in QCD
• Precise predictions for ${\Lambda }_b\to {\Lambda }_c$ semileptonic decays
• The CKM parameters in the SMEFT
• QCD Sum Rule Analysis of the Subleading Isgur-Wise Form Factor ${\chi }_2(v\cdot v^{\prime })$
• The Subleading Isgur-Wise Form Factor ${\xi }_3(v\cdot v^{\prime })$ and its Implications for the Decays $\bar{B}\to D^{(\ast )}\ell \bar{\nu }$
• Semileptonic $B_{(s)}$ decays to excited charmed mesons with $e,\mu ,\tau$ and searching for new physics with $R(D^{\ast \ast })$
• The Subleading Isgur-Wise Form Factor ${\chi }_3(v\cdot v^{\prime })$ to Order ${\alpha }_s$ in QCD Sum Rules
• Model independent analysis of semileptonic $B$ decays to $D^{\ast \ast }$ for arbitrary new physics
• Model independent New Physics analysis in ${\Lambda }_b\to \Lambda {\mu }^{+}{\mu }^{-}$ decay
• On the angular distribution of ${\Lambda }_b\to \Lambda (\to N\pi ){\tau }^{+}{\tau }^{-}$ decay
• Testing lepton flavour universality in semileptonic ${\Lambda }_b\to {\Lambda }_c^{\ast }$ decays
• Reconstruction of semileptonically decaying beauty hadrons produced in high energy pp collisions
• Impact of leptonic $\tau$ decays on the distribution of $B\to P\mu \bar{\nu }$ decays

Cited by in corpus (18)

• On the single leptoquark solutions to the $B$-physics anomalies
• EOS -- A Software for Flavor Physics Phenomenology
• ${\Lambda }_b\to {\Lambda }_c^{\ast }(2595,2625){\ell }^{-}\bar{\nu }$ form factors from lattice QCD
• The measurable angular distribution of ${\Lambda }_b^0\to {\Lambda }_c^{+}(\to {\Lambda }^0{\pi }^{+}){\tau }^{-}(\to {\pi }^{-}{\nu }_{\tau }){\bar{\nu }}_{\tau }$ decay
• Hadron and lepton tensors in semileptonic decays including new physics
• The role of right-handed neutrinos in $b\to c\tau (\pi {\nu }_{\tau },\rho {\nu }_{\tau },\mu {\bar{\nu }}_{\mu }{\nu }_{\tau }){\bar{\nu }}_{\tau }$ from visible final-state kinematics
• New physics and the tau polarization vector in $b\to c\tau {\bar{\nu }}_{\tau }$ decays
• Charm-baryon semileptonic decays and the strange ${\Lambda }^{\ast }$ resonances: New insights from lattice QCD
• Constraining $|V_{cs}|$ and physics beyond the Standard Model from exclusive (semi)leptonic charm decays
• Time-reversal asymmetries in ${\Lambda }_b$ semileptonic decays
• New physics effects on ${\Lambda }_b\to {\Lambda }_c^{\ast }\tau {\bar{\nu }}_{\tau }$ decays
• Sizable Time-reversal violating effects in bottom baryon decays
• Extracting maximum information from polarised baryon decays via amplitude analysis: the ${\Lambda }_c^{+}\to p{K}^{-}{\pi }^{+}$ case
• New physics in the angular distribution of $B_c^{-}\to J/\psi (\to {\mu }^{+}{\mu }^{-}){\tau }^{-}(\to {\pi }^{-}{\nu }_{\tau }){\bar{\nu }}_{\tau }$ decay
• $B_c^{-}\to J/\psi (\to {\mu }^{+}{\mu }^{-}){\tau }^{-}(\to {\pi }^{-}{\nu }_{\tau },{\rho }^{-}{\nu }_{\tau },{\ell }^{-}{\bar{\nu }}_{\ell }{\nu }_{\tau }){\bar{\nu }}_{\tau }$ decays with visible final-state kinematics
• An Imperative study of the angular observables in ${\Lambda }_b\to {\Lambda }_c^{+}(\to \Lambda {\pi }^{+}){\ell }^{-}{\bar{\nu }}_{\ell }$ decay and probing the footprint of new physics
• Relations between $b\to c\tau \nu$ Decay Modes in Scalar Models
• Semileptonic neutral current decays of ${\Xi }_b$ with dileptons or dineutrinos in the final state