Thomas Mannel
Current Organizations / Institutes
The organizations/institutes from the scholar's latest article
Previous Organizations / Institutes
The organizations / institutes from the scholar's other articles in the past ten years
Research Subjects
Research Interests
Thomas Mannel has a total of 57 co-authors. Here are the top co-authors by number of shared publications:
- Alexander Khodjamirian
Universität Siegen
11 shared publications - Kimberley Vos
Universiteit Maastricht
8 shared publications - Danny van Dyk
Durham University
6 shared publications - Ilija S. Milutin
Universität Siegen
6 shared publications - Rusa Mandal
Department of Physics Indian Institute of Technology Gandhinagar 382355 Gujarat India
6 shared publications - Nico Gubernari
Universität Bonn
4 shared publications
Latest Publications
- Open Access
- 9 September 2026
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (9) , 116
Extending the kinetic mass to higher orders in 1/mQ
A bstract: Currently, the kinetic mass is defined in terms of the pole mass and operators at order $$1/{m}_{Q}^{2}$$ , which are known to N 3 LO accuracy in α s . At the same time, the Heavy Quark Expansion (HQE) for inclusive semileptonic decays is known up to and including terms of order $$1/{m}_{Q}^{5}$$ . Therefore, it is desirable to extend the definition of the kinetic mass to higher orders in 1/ m Q . The original kinetic mass is based on the hadron-mass formula in Heavy Quark Effective Theory (HQET). However, the HQE is formulated in terms of matrix elements defined in full QCD to avoid the appearance of non-local matrix elements. To match this, we develop a definition of the kinetic mass rooted in full QCD. Starting from the hadron-mass formula derived from the energy-momentum tensor of full QCD, we define a relation between a general mass and the pole mass. Using a simple cut-off scheme, we compute a generalized kinetic mass at one loop to all powers of 1/ m Q , which reproduces the well-known results for the kinetic mass up to $$1/{m}_{Q}^{2}$$ . Our approach opens the road to a consistent use of the kinetic mass at higher-orders in the heavy quark expansion.- 9 September 2026
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2026 (9) , 116
Open AccessExtending the kinetic mass to higher orders in 1/mQ
A bstract: Currently, the kinetic mass is defined in terms of the pole mass and operators at order $$1/{m}_{Q}^{2}$$ , which are known to N 3 LO accuracy in α s . At the same time, the Heavy Quark Expansion (HQE) for inclusive semileptonic decays is known up to and including terms of order $$1/{m}_{Q}^{5}$$ . Therefore, it is desirable to extend the definition of the kinetic mass to higher orders in 1/ m Q . The original kinetic mass is based on the hadron-mass formula in Heavy Quark Effective Theory (HQET). However, the HQE is formulated in terms of matrix elements defined in full QCD to avoid the appearance of non-local matrix elements. To match this, we develop a definition of the kinetic mass rooted in full QCD. Starting from the hadron-mass formula derived from the energy-momentum tensor of full QCD, we define a relation between a general mass and the pole mass. Using a simple cut-off scheme, we compute a generalized kinetic mass at one loop to all powers of 1/ m Q , which reproduces the well-known results for the kinetic mass up to $$1/{m}_{Q}^{2}$$ . Our approach opens the road to a consistent use of the kinetic mass at higher-orders in the heavy quark expansion. - Open Access
- 1 April 2026
- Published by Jagiellonian University in Acta Physica Polonica B Proceedings Supplement
- Vol. 19 (4)
A Dispersive Approach to the Giant Localized CP Violation in \(B^\pm \to K^\pm \pi ^+\pi ^-\)In this article, we review our recent dispersive analysis of the large localized CP-violating asymmetries observed by LHCb in \(B^{\pm } \to K^{\pm }\pi ^+\pi ^-\) decays. Low-energy \(\pi \pi \) final-state interactions are treated in a model-independent way, and the weak decay is described as a short-distance source. By fitting angular-projected data, we reproduce the Dalitz-plot CP-asymmetry pattern at low \(m_{\pi \pi }\). Our framework highlights the essential role of the non-resonant isospin-\(2\) \(S\) wave, ensures unitarity, and can be extended to other three-body decays. Published by the Jagiellonian University 2026 authors- 1 April 2026
- Published by Jagiellonian University in Acta Physica Polonica B Proceedings Supplement
- Vol. 19 (4)
Open AccessA Dispersive Approach to the Giant Localized CP Violation in \(B^\pm \to K^\pm \pi ^+\pi ^-\)In this article, we review our recent dispersive analysis of the large localized CP-violating asymmetries observed by LHCb in \(B^{\pm } \to K^{\pm }\pi ^+\pi ^-\) decays. Low-energy \(\pi \pi \) final-state interactions are treated in a model-independent way, and the weak decay is described as a short-distance source. By fitting angular-projected data, we reproduce the Dalitz-plot CP-asymmetry pattern at low \(m_{\pi \pi }\). Our framework highlights the essential role of the non-resonant isospin-\(2\) \(S\) wave, ensures unitarity, and can be extended to other three-body decays. Published by the Jagiellonian University 2026 authors - Open Access
- 20 March 2026
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 136 (11) , 111901
Understanding Large Localized C P Violation in B ± → K ± π + π − Using Dispersive Methods
We utilize the universality of pion-pion ( π π ) final-state interactions at small invariant masses to understand the enhanced localized C P violation in B ± → K ± π + π − , using a dispersive approach. From a fit to the integrated C P -asymmetry data, we successfully predict the Dalitz-plot kinematic distribution of the asymmetry in the low-energy π π region, including the large localized C P violation recently observed by LHCb. An essential role is played by the contributions of isospin 2. This formalism, whose parameters have a physical meaning, can be adapted straightforwardly to other systems with C P violation enhanced by final-state interactions.
- 20 March 2026
- Published by American Physical Society (APS) in Physical Review Letters
- Vol. 136 (11) , 111901
Open AccessUnderstanding Large Localized C P Violation in B ± → K ± π + π − Using Dispersive Methods
We utilize the universality of pion-pion ( π π ) final-state interactions at small invariant masses to understand the enhanced localized C P violation in B ± → K ± π + π − , using a dispersive approach. From a fit to the integrated C P -asymmetry data, we successfully predict the Dalitz-plot kinematic distribution of the asymmetry in the low-energy π π region, including the large localized C P violation recently observed by LHCb. An essential role is played by the contributions of isospin 2. This formalism, whose parameters have a physical meaning, can be adapted straightforwardly to other systems with C P violation enhanced by final-state interactions.
- Open Access
- 4 August 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (8) , 1-59
D → Pℓ+ℓ− decays assisted by QCD light-cone sum rules
We suggest a new method to analyse the rare D (s) → Pℓ + ℓ − decays (P = π, K), combining QCD light-cone sum rules (LCSR) with hadronic dispersion relations. As our main study case, we consider the D + → π + ℓ + ℓ − mode which attracts much of interest from the point of view of GIM cancellation and potential new sources of the FCNC c → u transitions. The hadronic amplitude of this decay is dominated by the combination of weak annihilation with the emission of a virtual photon. This D + → π + γ ∗ amplitude is calculated at spacelike photon virtualities, −q 2 ≫ $$ {\Lambda}_{\textrm{QCD}}^2 $$ , using LCSR with pion distribution amplitudes. The LCSR results are then fitted to the hadronic dispersion relation in the variable q 2. The fit allows us to determine relative phases of the ρ-, ω- and ϕ-meson terms and to estimate the contributions of heavier hadronic states. The latter are parameterized in two different ways: first, with a z-expansion and second, using a model with excited vector-meson resonances. The resulting D + → π + ℓ + ℓ − width obtained from the LCSR-assisted dispersion relation is not much smaller than the current upper bound measured by LHCb collaboration. In comparison with our result for the dominant D + → π + γ ∗ transition, the contribution induced by the short distance c → uℓ + ℓ − quark transition generated by the effective O 9 operator in Standard Model turns out to be practically invisible. To detect its effect, one readily needs an enhancement of the coefficient C 9 from non-standard effects by many orders of magnitude. We also establish new U-spin symmetry relations between the amplitudes of D → Pℓ + ℓ − decays and apply our method to the Cabibbo-favoured modes $$ {D}_s^{+}\to {\pi}^{+}{\ell}^{+}{\ell}^{-} $$ and $$ {D}^0\to {\overline{K}}^0{\ell}^{+}{\ell}^{-} $$ which proceed via the same weak annihilation mechanism.- 4 August 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (8) , 1-59
Open AccessD → Pℓ+ℓ− decays assisted by QCD light-cone sum rules
We suggest a new method to analyse the rare D (s) → Pℓ + ℓ − decays (P = π, K), combining QCD light-cone sum rules (LCSR) with hadronic dispersion relations. As our main study case, we consider the D + → π + ℓ + ℓ − mode which attracts much of interest from the point of view of GIM cancellation and potential new sources of the FCNC c → u transitions. The hadronic amplitude of this decay is dominated by the combination of weak annihilation with the emission of a virtual photon. This D + → π + γ ∗ amplitude is calculated at spacelike photon virtualities, −q 2 ≫ $$ {\Lambda}_{\textrm{QCD}}^2 $$ , using LCSR with pion distribution amplitudes. The LCSR results are then fitted to the hadronic dispersion relation in the variable q 2. The fit allows us to determine relative phases of the ρ-, ω- and ϕ-meson terms and to estimate the contributions of heavier hadronic states. The latter are parameterized in two different ways: first, with a z-expansion and second, using a model with excited vector-meson resonances. The resulting D + → π + ℓ + ℓ − width obtained from the LCSR-assisted dispersion relation is not much smaller than the current upper bound measured by LHCb collaboration. In comparison with our result for the dominant D + → π + γ ∗ transition, the contribution induced by the short distance c → uℓ + ℓ − quark transition generated by the effective O 9 operator in Standard Model turns out to be practically invisible. To detect its effect, one readily needs an enhancement of the coefficient C 9 from non-standard effects by many orders of magnitude. We also establish new U-spin symmetry relations between the amplitudes of D → Pℓ + ℓ − decays and apply our method to the Cabibbo-favoured modes $$ {D}_s^{+}\to {\pi}^{+}{\ell}^{+}{\ell}^{-} $$ and $$ {D}^0\to {\overline{K}}^0{\ell}^{+}{\ell}^{-} $$ which proceed via the same weak annihilation mechanism. - Open Access
- 27 May 2025
- Published by American Physical Society (APS) in Physical Review D
- Vol. 111 (9)
QCD corrections for subleading powers in for the nonleptonic transitionWe compute next-to-leading order QCD corrections to the 1 / m b 2 terms of the heavy quark expansion, for the contribution to inclusive nonleptonic bottom hadron decays, induced by the charged-current operators mediating the b → c c ¯ s transition. Their contributions to the lifetimes are Cabibbo favored and have large Wilson coefficients, but they have not been computed before, since the presence of two heavy quarks in the final state makes this calculation technically demanding. This work adds the last missing piece of the full NLO terms at 1 / m b 2 in the heavy quark expansion of B -hadron lifetimes. We obtain analytical results with full dependence on the final-state charm quark mass. Published by the American Physical Society 2025
- 27 May 2025
- Published by American Physical Society (APS) in Physical Review D
- Vol. 111 (9)
Open AccessQCD corrections for subleading powers in for the nonleptonic transitionWe compute next-to-leading order QCD corrections to the 1 / m b 2 terms of the heavy quark expansion, for the contribution to inclusive nonleptonic bottom hadron decays, induced by the charged-current operators mediating the b → c c ¯ s transition. Their contributions to the lifetimes are Cabibbo favored and have large Wilson coefficients, but they have not been computed before, since the presence of two heavy quarks in the final state makes this calculation technically demanding. This work adds the last missing piece of the full NLO terms at 1 / m b 2 in the heavy quark expansion of B -hadron lifetimes. We obtain analytical results with full dependence on the final-state charm quark mass. Published by the American Physical Society 2025
- Open Access
$D\to P \ell^+\ell^-$ decays assisted by QCD light-cone sum rules
We suggest a new method to analyse the rare $D_{(s)}\to P \ell^+\ell^-$ decays ($P=π,K$), combining QCD light-cone sum rules (LCSR) with hadronic dispersion relations. As our main study case, we consider the $D^+\toπ^+\ell^+\ell^-$ mode which attracts much of interest from the point of view of GIM cancellation and potential new sources of the FCNC $c\to u$ transitions. The hadronic amplitude of this decay is dominated by the combination of weak annihilation with the emission of a virtual photon. This $D^+\to π^+γ^*$ amplitude is calculated at spacelike photon virtualities, $-q^2 \gg Λ_{QCD}^2$, using LCSR with pion distribution amplitudes. The LCSR results are then fitted to the hadronic dispersion relation in the variable $q^2$. The fit allows us to determine relative phases of the $ρ$-,$ω$- and $φ$-meson terms and to estimate the contributions of heavier hadronic states. The latter are parameterized in two different ways: first, with a $z$-expansion and second, using a model with excited vector-meson resonances. The resulting $D^+\toπ^+\ell^+\ell^-$ width obtained from the LCSR-assisted dispersion relation is not much smaller than the current upper bound measured by LHCb collaboration. In comparison with our result for the dominant $D^+\to π^+γ^*$ transition, the contribution induced by the short distance $c\to u \ell^+\ell^-$ quark transition generated by the effective $O_9$ operator in Standard Model turns out to be practically invisible. To detect its effect, one readily needs a enhancement of the coefficient $C_9$ from non-standard effects by many orders of magnitude. We also establish new $U$-spin symmetry relations between the amplitudes of $D\to P \ell^+\ell^-$ decays and apply our method to the Cabibbo-favoured modes $D^+_s\toπ^+\ell^+\ell^-$ and $D^0\to\bar{K}^0\ell^+\ell^-$ which proceed via the same weak annihilation mechanism.Open Access$D\to P \ell^+\ell^-$ decays assisted by QCD light-cone sum rules
We suggest a new method to analyse the rare $D_{(s)}\to P \ell^+\ell^-$ decays ($P=π,K$), combining QCD light-cone sum rules (LCSR) with hadronic dispersion relations. As our main study case, we consider the $D^+\toπ^+\ell^+\ell^-$ mode which attracts much of interest from the point of view of GIM cancellation and potential new sources of the FCNC $c\to u$ transitions. The hadronic amplitude of this decay is dominated by the combination of weak annihilation with the emission of a virtual photon. This $D^+\to π^+γ^*$ amplitude is calculated at spacelike photon virtualities, $-q^2 \gg Λ_{QCD}^2$, using LCSR with pion distribution amplitudes. The LCSR results are then fitted to the hadronic dispersion relation in the variable $q^2$. The fit allows us to determine relative phases of the $ρ$-,$ω$- and $φ$-meson terms and to estimate the contributions of heavier hadronic states. The latter are parameterized in two different ways: first, with a $z$-expansion and second, using a model with excited vector-meson resonances. The resulting $D^+\toπ^+\ell^+\ell^-$ width obtained from the LCSR-assisted dispersion relation is not much smaller than the current upper bound measured by LHCb collaboration. In comparison with our result for the dominant $D^+\to π^+γ^*$ transition, the contribution induced by the short distance $c\to u \ell^+\ell^-$ quark transition generated by the effective $O_9$ operator in Standard Model turns out to be practically invisible. To detect its effect, one readily needs a enhancement of the coefficient $C_9$ from non-standard effects by many orders of magnitude. We also establish new $U$-spin symmetry relations between the amplitudes of $D\to P \ell^+\ell^-$ decays and apply our method to the Cabibbo-favoured modes $D^+_s\toπ^+\ell^+\ell^-$ and $D^0\to\bar{K}^0\ell^+\ell^-$ which proceed via the same weak annihilation mechanism. - Open Access
- 25 February 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (2) , 1-2
Erratum to: Inclusive semileptonic $ b\to c\ell \overline{\nu} $ decays to order $ 1/{m}_b^5 $A correction to this paper has been published: https://doi.org/10.1007/JHEP02(2024)226
- 25 February 2025
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2025 (2) , 1-2
Open AccessErratum to: Inclusive semileptonic $ b\to c\ell \overline{\nu} $ decays to order $ 1/{m}_b^5 $A correction to this paper has been published: https://doi.org/10.1007/JHEP02(2024)226
- Open Access
- 17 December 2024
- Published by Sissa Medialab Srl
- Vol. 476, 471
Pushing the Heavy Quark Expansion for $b\to c\ell\bar{\nu}$ to higher order in $1/m_b$The Heavy Quark Expansion (HQE) is the major tool to perform calculations for inclusive semileptonic $B\to X_cl\bar{\nu}$ and, consequently, for precision determinations of the CKM matrix element $V_{cb}$. To further improve precision, we pushed the expansion to $1/m_b^5$ to include even higher order terms in the HQE. Notably, at $1/m_b^5$, ``intrinsic charm'' (IC) contributions proportional to $1/(m_b^3m_c^2)$ occur, which are numerically expected to be sizeable. We will therefore firstly discuss the determination of a reduced set of HQE parameters at $1/m_b^5$, employing Reparametrisation Invariance (RPI) to this end. Consequently, we will show how the IC and ``genuine" $1/m_b^5$ contribute to the different kinematical moments of $B\to X_cl\bar{\nu}$, focusing in this work on the lepton energy $E_l$ moments. Using the ``lowest-lying state saturation ansatz'' (LLSA), we estimate the size of these contributions and observe a partial cancellation between the IC and ``genuine'' $1/m_b^5$ contributions, leading to an overall small contribution.- 17 December 2024
- Published by Sissa Medialab Srl
- Vol. 476, 471
Open AccessPushing the Heavy Quark Expansion for $b\to c\ell\bar{\nu}$ to higher order in $1/m_b$The Heavy Quark Expansion (HQE) is the major tool to perform calculations for inclusive semileptonic $B\to X_cl\bar{\nu}$ and, consequently, for precision determinations of the CKM matrix element $V_{cb}$. To further improve precision, we pushed the expansion to $1/m_b^5$ to include even higher order terms in the HQE. Notably, at $1/m_b^5$, ``intrinsic charm'' (IC) contributions proportional to $1/(m_b^3m_c^2)$ occur, which are numerically expected to be sizeable. We will therefore firstly discuss the determination of a reduced set of HQE parameters at $1/m_b^5$, employing Reparametrisation Invariance (RPI) to this end. Consequently, we will show how the IC and ``genuine" $1/m_b^5$ contribute to the different kinematical moments of $B\to X_cl\bar{\nu}$, focusing in this work on the lepton energy $E_l$ moments. Using the ``lowest-lying state saturation ansatz'' (LLSA), we estimate the size of these contributions and observe a partial cancellation between the IC and ``genuine'' $1/m_b^5$ contributions, leading to an overall small contribution. - Open Access
- 7 November 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 110 (9)
QCD corrections at subleading power for inclusive nonleptonic decaysIn this paper we compute the next-to-leading order (NLO) QCD corrections for the inclusive nonleptonic decay rates of B hadrons at subleading power of the heavy quark expansion. In particular, we discuss the coefficient of the chromomagnetic moment parameter μ G , which has a large uncertainty at leading order due to its dependence on the renormalization scale. We find that the renormalization-scale dependence of this coefficient is significantly reduced, thereby reducing the theoretical uncertainty of the coefficient and, consequently, the rates. The sign of the coefficient becomes stable, and we estimate that the NLO corrections will increase the decay rates by around 2%. Published by the American Physical Society 2024
- 7 November 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 110 (9)
Open AccessQCD corrections at subleading power for inclusive nonleptonic decaysIn this paper we compute the next-to-leading order (NLO) QCD corrections for the inclusive nonleptonic decay rates of B hadrons at subleading power of the heavy quark expansion. In particular, we discuss the coefficient of the chromomagnetic moment parameter μ G , which has a large uncertainty at leading order due to its dependence on the renormalization scale. We find that the renormalization-scale dependence of this coefficient is significantly reduced, thereby reducing the theoretical uncertainty of the coefficient and, consequently, the rates. The sign of the coefficient becomes stable, and we estimate that the NLO corrections will increase the decay rates by around 2%. Published by the American Physical Society 2024
- Open Access
- 23 October 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (10) , 1-24
Quark-hadron duality violations and higher-order 1/mb corrections in inclusive semileptonic B decays
The theoretical description and data for inclusive semileptonic B decays have reached incredible precision. This motivated us to re-animate the discussion of possible Quark-Hadron Duality violations. There seems that there is currently no evidence of a failure of the Heavy Quark Expansion (HQE) used to compute observables for these decays. However, we might arrive at a point where an asymptotic behaviour of the HQE would limit a further increase of precision. We discuss this possibility and suggest a simple model, which can be used to study the effects of higher orders in the 1/m b expansion and possible quark-hadron duality violations. We devise observables sensitive only to such higher-order effects to test the behaviour of the HQE. Using these observables we obtain a first estimate of possible quark-hadron duality violations using the measured q 2 moments.
- 23 October 2024
- Published by Springer Nature in Journal of High Energy Physics
- Vol. 2024 (10) , 1-24
Open AccessQuark-hadron duality violations and higher-order 1/mb corrections in inclusive semileptonic B decays
The theoretical description and data for inclusive semileptonic B decays have reached incredible precision. This motivated us to re-animate the discussion of possible Quark-Hadron Duality violations. There seems that there is currently no evidence of a failure of the Heavy Quark Expansion (HQE) used to compute observables for these decays. However, we might arrive at a point where an asymptotic behaviour of the HQE would limit a further increase of precision. We discuss this possibility and suggest a simple model, which can be used to study the effects of higher orders in the 1/m b expansion and possible quark-hadron duality violations. We devise observables sensitive only to such higher-order effects to test the behaviour of the HQE. Using these observables we obtain a first estimate of possible quark-hadron duality violations using the measured q 2 moments.