Rafel Escribano
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
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Rafel Escribano has a total of 170 co-authors. Here are the top co-authors by number of shared publications:
- Emilio Royo
Grup de Física Teòrica Departament de Física Universitat Autònoma de Barcelona E-08193 Bellaterra (Barcelona Spain
15 shared publications - Pablo Sanchez-Puertas
Departamento de Física Atómica, Molecular y Nuclear, Universidad de Granada, Granada, Spain
10 shared publications - Pere Masjuan
Universitat Autónoma de Barcelona
10 shared publications - Matthias Jamin
Faculty of Physics University of Vienna Boltzmanngasse 5 A-1090 Wien Austria
8 shared publications A. Bramon
Grup de Física Teórica, Universitat Autónoma de Barcelona, Bellaterra, Spain
7 shared publications- Sergi Gonzàlez-Solís
Departament de Física Quàntica i Astrofísica (FQA) Universitat de Barcelona (UB) c.Martí i Franquès 1 08028 Barcelona Spain
7 shared publications
Latest Publications
- Open Access
- 3 December 2025
- Published by American Physical Society (APS) in Physical Review D
- Vol. 112 (11)
Assessment of the a 2 ( 1320 ) tensor-meson contribution to η / η ′ → π 0 γ γ decays
In light of the recent measurement of the η → π 0 γ γ decay by the KLOE-2 Collaboration, a previous analysis including vector- and scalar-meson exchange contributions using the vector meson dominance and linear sigma model frameworks, respectively, is extended in the present study to incorporate the effects of the a 2 ( 1320 ) tensor meson within a chiral context. Although the individual contribution of the a 2 is negligible, its destructive interference with the vector-meson resonances is found to be significant, representing approximately 18% of the total signal and substantially affecting the diphoton invariant-mass distribution, especially at low m γ γ 2 values. The total decay rate is calculated to be Γ ( η → π 0 γ γ ) = 0.154 ( 22 ) eV , which corresponds to a branching ratio of BR ( η → π 0 γ γ ) = 1.17 ( 17 ) × 10 − 4 . This result is approximately 5 σ below the reported value of the particle data group, 2.55 ( 22 ) × 10 − 4 , while it is in very good agreement with the KLOE-2 measurement, 0.98 ( 1 1 stat ) ( 1 4 syst ) × 10 − 4 . In contrast, the total contribution of the a 2 is found to be negligible in η ′ → π 0 γ γ , as this process is completely dominated by the exchange of an on-shell ω vector resonance.
- 3 December 2025
- Published by American Physical Society (APS) in Physical Review D
- Vol. 112 (11)
Open AccessAssessment of the a 2 ( 1320 ) tensor-meson contribution to η / η ′ → π 0 γ γ decays
In light of the recent measurement of the η → π 0 γ γ decay by the KLOE-2 Collaboration, a previous analysis including vector- and scalar-meson exchange contributions using the vector meson dominance and linear sigma model frameworks, respectively, is extended in the present study to incorporate the effects of the a 2 ( 1320 ) tensor meson within a chiral context. Although the individual contribution of the a 2 is negligible, its destructive interference with the vector-meson resonances is found to be significant, representing approximately 18% of the total signal and substantially affecting the diphoton invariant-mass distribution, especially at low m γ γ 2 values. The total decay rate is calculated to be Γ ( η → π 0 γ γ ) = 0.154 ( 22 ) eV , which corresponds to a branching ratio of BR ( η → π 0 γ γ ) = 1.17 ( 17 ) × 10 − 4 . This result is approximately 5 σ below the reported value of the particle data group, 2.55 ( 22 ) × 10 − 4 , while it is in very good agreement with the KLOE-2 measurement, 0.98 ( 1 1 stat ) ( 1 4 syst ) × 10 − 4 . In contrast, the total contribution of the a 2 is found to be negligible in η ′ → π 0 γ γ , as this process is completely dominated by the exchange of an on-shell ω vector resonance.
- Open AccessAssessment of the $a_{2}(1320)$ tensor-meson contribution to $η/η^{\prime}\toπ^{0}γγ$ decaysIn light of the recent measurement of the $η\toπ^{0}γγ$ decay by the KLOE-2 Collaboration, a previous analysis including vector- and scalar-meson exchange contributions using the VMD and L$σ$M frameworks, respectively, is extended in the present study to incorporate the effects of the $a_{2}(1320)$ tensor meson within a chiral context. Although the individual contribution of the $a_{2}$ is negligible, its destructive interference with the vector-meson resonances is found to be significant, representing approximately $18\%$ of the total signal and substantially affecting the diphoton invariant-mass distribution, especially at low $m_{γγ}^{2}$ values. The total decay rate is calculated to be $Γ(η\toπ^{0}γγ)=0.154(22)$ eV, which corresponds to a branching ratio of ${\rm BR}(η\toπ^{0}γγ)=1.17(17)\times10^{-4}$. This result is approximately $5σ$ below the reported value of the PDG, $2.55(22)\times10^{-4}$, while it is in very good agreement with the KLOE-2 measurement, $0.98(11_{\rm stat})(14_{\rm syst})\times10^{-4}$. In contrast, the total contribution of the $a_{2}$ is found to be negligible in $η^{\prime}\toπ^{0}γγ$, as this process is completely dominated by the exchange of an on-shell $ω$ vector resonance.Open AccessAssessment of the $a_{2}(1320)$ tensor-meson contribution to $η/η^{\prime}\toπ^{0}γγ$ decaysIn light of the recent measurement of the $η\toπ^{0}γγ$ decay by the KLOE-2 Collaboration, a previous analysis including vector- and scalar-meson exchange contributions using the VMD and L$σ$M frameworks, respectively, is extended in the present study to incorporate the effects of the $a_{2}(1320)$ tensor meson within a chiral context. Although the individual contribution of the $a_{2}$ is negligible, its destructive interference with the vector-meson resonances is found to be significant, representing approximately $18\%$ of the total signal and substantially affecting the diphoton invariant-mass distribution, especially at low $m_{γγ}^{2}$ values. The total decay rate is calculated to be $Γ(η\toπ^{0}γγ)=0.154(22)$ eV, which corresponds to a branching ratio of ${\rm BR}(η\toπ^{0}γγ)=1.17(17)\times10^{-4}$. This result is approximately $5σ$ below the reported value of the PDG, $2.55(22)\times10^{-4}$, while it is in very good agreement with the KLOE-2 measurement, $0.98(11_{\rm stat})(14_{\rm syst})\times10^{-4}$. In contrast, the total contribution of the $a_{2}$ is found to be negligible in $η^{\prime}\toπ^{0}γγ$, as this process is completely dominated by the exchange of an on-shell $ω$ vector resonance.
- Open Access
- 11 March 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 109 (5) , 053003
Radiative corrections to the () decaysThe radiative corrections to the (, ) decays are calculated for the first time including the structure-dependent real photon corrections, which are obtained using resonance chiral theory. Our results, whose uncertainty is dominated by the model dependence of the resummation of the radiative corrections and the missing virtual structure-dependent contributions, allow for precise tests of Cabibbo-Kobayashi-Maskawa unitarity, lepton flavor universality, and nonstandard interactions.- 11 March 2024
- Published by American Physical Society (APS) in Physical Review D
- Vol. 109 (5) , 053003
Open AccessRadiative corrections to the () decaysThe radiative corrections to the (, ) decays are calculated for the first time including the structure-dependent real photon corrections, which are obtained using resonance chiral theory. Our results, whose uncertainty is dominated by the model dependence of the resummation of the radiative corrections and the missing virtual structure-dependent contributions, allow for precise tests of Cabibbo-Kobayashi-Maskawa unitarity, lepton flavor universality, and nonstandard interactions. - Open AccessRadiative corrections to the $τ^-\to (P_1P_2)^-ν_τ$ ($P_{1,2}=π, K$) decaysThe radiative corrections to the $τ^-\to (P_1P_2)^-ν_τ$ ($P_{1,2}=π, K$) decays are calculated for the first time including the structure-dependent real photon corrections, which are obtained using Resonance Chiral Theory. Our results, whose uncertainty is dominated by the model-dependence of the resummation of the radiative corrections and the missing virtual structure-dependent contributions, allow for precise tests of CKM unitarity, lepton flavour universality and non-standard interactions.Open AccessRadiative corrections to the $τ^-\to (P_1P_2)^-ν_τ$ ($P_{1,2}=π, K$) decaysThe radiative corrections to the $τ^-\to (P_1P_2)^-ν_τ$ ($P_{1,2}=π, K$) decays are calculated for the first time including the structure-dependent real photon corrections, which are obtained using Resonance Chiral Theory. Our results, whose uncertainty is dominated by the model-dependence of the resummation of the radiative corrections and the missing virtual structure-dependent contributions, allow for precise tests of CKM unitarity, lepton flavour universality and non-standard interactions.
- Open Access
- 6 February 2024
- Published by Sissa Medialab Srl
- Vol. 413, 024
Theoretical analysis of $\eta^{(\prime)}\to\pi^0l^+l^-$ and $\eta^{\prime}\to\eta l^+l^-$ decays, and new-physics signatures via $CP$ violationA complete theoretical analysis of the $C$-conserving semileptonic decays $\eta^{(\prime)}\to\pi^0l^+l^-$ and $\eta^\prime\to\eta l^+l^-$ ($l=e$ or $\mu$) is carried out within the framework of the Vector Meson Dominance (VMD) model. An existing phenomenological model is used to parametrise the VMD coupling constants and the associated numerical values are obtained from an optimisation fit to $V\to P\gamma$ and $P\to V\gamma$ radiative decays ($V=\rho^0$, $\omega$, $\phi$ and $P=\pi^0$, $\eta$, $\eta^{\prime}$). Theoretical predictions for the six decay widths and associated dilepton energy spectra are calculated and presented. In addition, we investigate the prospect of observing new-physics signatures via $CP$ violation in $\eta^{(\prime)}\to\pi^0\mu^+\mu^-$ and $\eta^\prime\to\eta\mu^+\mu^-$ decays at the REDTOP experiment. We make use of the SMEFT to parametrise the new-physics $CP$-violating effects and find that the projected REDTOP statistics are not competitive with respect to nEDM experiments for these particular processes.- 6 February 2024
- Published by Sissa Medialab Srl
- Vol. 413, 024
Open AccessTheoretical analysis of $\eta^{(\prime)}\to\pi^0l^+l^-$ and $\eta^{\prime}\to\eta l^+l^-$ decays, and new-physics signatures via $CP$ violationA complete theoretical analysis of the $C$-conserving semileptonic decays $\eta^{(\prime)}\to\pi^0l^+l^-$ and $\eta^\prime\to\eta l^+l^-$ ($l=e$ or $\mu$) is carried out within the framework of the Vector Meson Dominance (VMD) model. An existing phenomenological model is used to parametrise the VMD coupling constants and the associated numerical values are obtained from an optimisation fit to $V\to P\gamma$ and $P\to V\gamma$ radiative decays ($V=\rho^0$, $\omega$, $\phi$ and $P=\pi^0$, $\eta$, $\eta^{\prime}$). Theoretical predictions for the six decay widths and associated dilepton energy spectra are calculated and presented. In addition, we investigate the prospect of observing new-physics signatures via $CP$ violation in $\eta^{(\prime)}\to\pi^0\mu^+\mu^-$ and $\eta^\prime\to\eta\mu^+\mu^-$ decays at the REDTOP experiment. We make use of the SMEFT to parametrise the new-physics $CP$-violating effects and find that the projected REDTOP statistics are not competitive with respect to nEDM experiments for these particular processes. - Open Access
- 6 February 2024
- Published by Sissa Medialab Srl
- Vol. 413, 027
A primer analysis of $\pi^0$-$\eta$-$\eta^{\prime}$ mixing from $V\!\rightarrow\!P\gamma$ and $P\!\rightarrow\!V\gamma$ decaysA primer analysis of $\pi^0$-$\eta$-$\eta^{\prime}$ mixing from $V\!\rightarrow\!P\gamma$ and $P\!\rightarrow\!V\gamma$ ($V=\rho$, $K^*$, $\omega$, $\phi$ and $P=\pi$, $K$, $\eta$, $\eta^{\prime}$) decays is performed using an enhanced phenomenological model that includes isospin-symmetry breaking. When the model is contrasted with the most recent experimental data for these radiative transitions, estimations for the mixing angles amongst the three pseudoscalar states with vanishing third-component of isospin are obtained. The current experimental uncertainties allow for isospin-symmetry violations with a confidence level of approximately $2.5\sigma$.- 6 February 2024
- Published by Sissa Medialab Srl
- Vol. 413, 027
Open AccessA primer analysis of $\pi^0$-$\eta$-$\eta^{\prime}$ mixing from $V\!\rightarrow\!P\gamma$ and $P\!\rightarrow\!V\gamma$ decaysA primer analysis of $\pi^0$-$\eta$-$\eta^{\prime}$ mixing from $V\!\rightarrow\!P\gamma$ and $P\!\rightarrow\!V\gamma$ ($V=\rho$, $K^*$, $\omega$, $\phi$ and $P=\pi$, $K$, $\eta$, $\eta^{\prime}$) decays is performed using an enhanced phenomenological model that includes isospin-symmetry breaking. When the model is contrasted with the most recent experimental data for these radiative transitions, estimations for the mixing angles amongst the three pseudoscalar states with vanishing third-component of isospin are obtained. The current experimental uncertainties allow for isospin-symmetry violations with a confidence level of approximately $2.5\sigma$. - Open Access
- 6 November 2023
- Published by American Physical Society (APS) in Physical Review D
- Vol. 108 (9) , 094006
Combined study of hadronic and decays by means of the analysis of semileptonic decaysWe perform a combined study of the two hadronic decays and using a detailed analysis of the semileptonic decays (, ) thanks to the high-statistics dataset provided by the BESIII Collaboration. We propose simple and suitable amplitude parametrizations of the studied reactions that shall be of interest to experimentalists for upcoming analyses. These new parametrizations are based on the naïve-factorization hypothesis and the description of the resulting matrix elements in terms of well-known hadronic form factors, with special emphasis on the scalar and vector cases. Such form factors account for two-body final-state interactions which fulfill analyticity, unitarity, and chiral symmetry constraints. As a result of our study, we find that the -wave contribution fits nicely within the naïve-factorization approach, whereas the -wave contribution requires complex Wilson coefficients that hint for possibly genuine three-body nonfactorizable effects. Our hypothesis is further supported by the examination of decays, where we achieve a description in overall good agreement with data.- 6 November 2023
- Published by American Physical Society (APS) in Physical Review D
- Vol. 108 (9) , 094006
Open AccessCombined study of hadronic and decays by means of the analysis of semileptonic decaysWe perform a combined study of the two hadronic decays and using a detailed analysis of the semileptonic decays (, ) thanks to the high-statistics dataset provided by the BESIII Collaboration. We propose simple and suitable amplitude parametrizations of the studied reactions that shall be of interest to experimentalists for upcoming analyses. These new parametrizations are based on the naïve-factorization hypothesis and the description of the resulting matrix elements in terms of well-known hadronic form factors, with special emphasis on the scalar and vector cases. Such form factors account for two-body final-state interactions which fulfill analyticity, unitarity, and chiral symmetry constraints. As a result of our study, we find that the -wave contribution fits nicely within the naïve-factorization approach, whereas the -wave contribution requires complex Wilson coefficients that hint for possibly genuine three-body nonfactorizable effects. Our hypothesis is further supported by the examination of decays, where we achieve a description in overall good agreement with data. - Open AccessA combined study of hadronic $D^+\to K^-π^+π^+$ and $D_s^+\to K^+K^+π^-$ decays by means of the analysis of semileptonic $D^+\to K^-π^+ \ell^+ν_\ell$ decaysWe perform a combined study of the two hadronic decays $D^+\to K^-π^+π^+$ and $D_s^+\to K^+K^+π^-$ using a detailed analysis of the semileptonic decays $D^+\to K^-π^+ \ell^+ν_\ell$ ($\ell=e, μ$) thanks to the high-statistics dataset provided by the BESIII Collaboration. We propose simple and suitable amplitude parametrizations of the studied reactions that shall be of interest to experimentalists for upcoming analyses. These new parametrizations are based on the naïve factorization hypothesis and the description of the resulting matrix elements in terms of well-known hadronic form factors, with special emphasis on the $Kπ$ scalar and vector cases. Such form factors account for two-body final state interactions which fulfill analyticity, unitarity and chiral symmetry constraints. As a result of our study, we find that the $P$-wave contribution fits nicely within the naïve-factorization approach, whereas the $S$-wave contribution requires complex Wilson coefficients that hint for possibly genuine three-body non-factorizable effects. Our hypothesis is further supported by the examination of $D_s^+\to K^+K^+π^-$ decays, where we achieve a description in overall good agreement with data.Open AccessA combined study of hadronic $D^+\to K^-π^+π^+$ and $D_s^+\to K^+K^+π^-$ decays by means of the analysis of semileptonic $D^+\to K^-π^+ \ell^+ν_\ell$ decaysWe perform a combined study of the two hadronic decays $D^+\to K^-π^+π^+$ and $D_s^+\to K^+K^+π^-$ using a detailed analysis of the semileptonic decays $D^+\to K^-π^+ \ell^+ν_\ell$ ($\ell=e, μ$) thanks to the high-statistics dataset provided by the BESIII Collaboration. We propose simple and suitable amplitude parametrizations of the studied reactions that shall be of interest to experimentalists for upcoming analyses. These new parametrizations are based on the naïve factorization hypothesis and the description of the resulting matrix elements in terms of well-known hadronic form factors, with special emphasis on the $Kπ$ scalar and vector cases. Such form factors account for two-body final state interactions which fulfill analyticity, unitarity and chiral symmetry constraints. As a result of our study, we find that the $P$-wave contribution fits nicely within the naïve-factorization approach, whereas the $S$-wave contribution requires complex Wilson coefficients that hint for possibly genuine three-body non-factorizable effects. Our hypothesis is further supported by the examination of $D_s^+\to K^+K^+π^-$ decays, where we achieve a description in overall good agreement with data.
- Open Access
- 22 December 2022
- Published by EDP Sciences in EPJ Web of Conferences
- Vol. 274, 06002
Searching for a leptophobicBboson throughη→π0γγandηʹ→π0γγdecays
The sensitivity of the decaysη→π0γγandηʹ→π0γγto a leptophobicBboson in the sub-GeV mass range is summarised in this work. By adding an explicitB-boson resonance exchange to the dominant Standard Model contribution from vector meson exchanges, and employing experimental measurements of the associated branching ratios, the current constraints on theB-boson massmBand coupling to Standard Model particlesαBare significantly improved. From these constraints and the analysis of the available experimentalγγinvariant mass distribution ofη→π0γγ, we conclude that a B-boson signature in the resonant mass rangemπ0≲mB≲mηis strongly suppressed and would be very difficult to experimentally identified. Theη΄→π0γγdecay is not as powerful as theη→π0γγat constrainingB-boson parameters belowmηbut allow exploring largerB-boson masses. Yet, the task of identifying aB-boson withmB∼mωwould be very challenging.
- 22 December 2022
- Published by EDP Sciences in EPJ Web of Conferences
- Vol. 274, 06002
Open AccessSearching for a leptophobicBboson throughη→π0γγandηʹ→π0γγdecays
The sensitivity of the decaysη→π0γγandηʹ→π0γγto a leptophobicBboson in the sub-GeV mass range is summarised in this work. By adding an explicitB-boson resonance exchange to the dominant Standard Model contribution from vector meson exchanges, and employing experimental measurements of the associated branching ratios, the current constraints on theB-boson massmBand coupling to Standard Model particlesαBare significantly improved. From these constraints and the analysis of the available experimentalγγinvariant mass distribution ofη→π0γγ, we conclude that a B-boson signature in the resonant mass rangemπ0≲mB≲mηis strongly suppressed and would be very difficult to experimentally identified. Theη΄→π0γγdecay is not as powerful as theη→π0γγat constrainingB-boson parameters belowmηbut allow exploring largerB-boson masses. Yet, the task of identifying aB-boson withmB∼mωwould be very challenging.
- Open AccessSensitivity of the $η^{(\prime)}\toπ^{0}γγ$ and $η^{\prime}\toηγγ$ decays to a sub-GeV leptophobic $U(1)_{B}$ bosonThe sensitivity of the rare decays $\eta^{(\prime)}\to\pi^{0}\gamma\gamma$ and $\eta^{\prime}\to\eta\gamma\gamma$ to signatures of a leptophobic $B$ boson in the MeV-GeV mass range is analyzed in this work. By adding an explicit $B$-boson resonance exchange, $\eta\to B\gamma\to\pi^{0}\gamma\gamma$, to the Standard Model contributions from vector and scalar meson exchanges, and employing experimental data for the associated branching ratios, it allows us to improve the current constraints on the $B$-boson mass $m_{B}$ and coupling to Standard Model particles $\alpha_{B}$. From these constraints and the analysis of the available experimental $\gamma\gamma$ invariant mass distribution, we show that a $B$-boson signature in the resonant mass range $m_{\pi^{0}}\lesssim m_{B}\lesssim m_{\eta}$ is strongly suppressed and would be very difficult to experimentally identify, assuming that the leptophobic $B$ boson only decays to Standard Model particles. In contrast, the limits outside this mass window are less stringent and the corresponding $t$- and $u$-channel signatures may still be observable in the data, as it occurs with the nonresonant Standard Model $\rho$, $\omega$ and $\phi$ meson exchanges. In addition, we make use of experimental data from the $\eta^{\prime}\to\pi^{0}\gamma\gamma$ and $\eta^{\prime}\to\eta\gamma\gamma$ decays to explore larger $B$-boson masses. Our results are relevant for the $B$-boson search programs at existing and forthcoming light-meson facilities, such as KLOE(-II) and Jefferson Lab Eta Factory experiments.Open AccessSensitivity of the $η^{(\prime)}\toπ^{0}γγ$ and $η^{\prime}\toηγγ$ decays to a sub-GeV leptophobic $U(1)_{B}$ bosonThe sensitivity of the rare decays $\eta^{(\prime)}\to\pi^{0}\gamma\gamma$ and $\eta^{\prime}\to\eta\gamma\gamma$ to signatures of a leptophobic $B$ boson in the MeV-GeV mass range is analyzed in this work. By adding an explicit $B$-boson resonance exchange, $\eta\to B\gamma\to\pi^{0}\gamma\gamma$, to the Standard Model contributions from vector and scalar meson exchanges, and employing experimental data for the associated branching ratios, it allows us to improve the current constraints on the $B$-boson mass $m_{B}$ and coupling to Standard Model particles $\alpha_{B}$. From these constraints and the analysis of the available experimental $\gamma\gamma$ invariant mass distribution, we show that a $B$-boson signature in the resonant mass range $m_{\pi^{0}}\lesssim m_{B}\lesssim m_{\eta}$ is strongly suppressed and would be very difficult to experimentally identify, assuming that the leptophobic $B$ boson only decays to Standard Model particles. In contrast, the limits outside this mass window are less stringent and the corresponding $t$- and $u$-channel signatures may still be observable in the data, as it occurs with the nonresonant Standard Model $\rho$, $\omega$ and $\phi$ meson exchanges. In addition, we make use of experimental data from the $\eta^{\prime}\to\pi^{0}\gamma\gamma$ and $\eta^{\prime}\to\eta\gamma\gamma$ decays to explore larger $B$-boson masses. Our results are relevant for the $B$-boson search programs at existing and forthcoming light-meson facilities, such as KLOE(-II) and Jefferson Lab Eta Factory experiments.