The LHCb experiment has recently presented new results on Lepton Universality Violation (LUV) in $$B \rightarrow K^{(*)} \ell ^+ \ell ^-$$ decays involving $$K_S$$ in the final state, which strengthen the recent evidence of LUV obtained in $$B^+ \rightarrow K^{+} \ell ^+ \ell ^-$$ decays and the previous measurements of $$B \rightarrow K^{*0} \ell ^+ \ell ^-$$ . While LUV observables in the Standard Model are theoretically clean, their predictions in New Physics scenarios are sensitive to the details of the hadronic dynamics, and in particular of the charming penguin contribution. In this work, we show how a conservative treatment of hadronic uncertainties is crucial not only to assess the significance of deviations from the Standard Model but also to obtain a conservative picture of the New Physics responsible for LUV. Adopting a very general parameterization of charming penguins, we find that: (i) current data hint at a sizable $$q^2$$ and helicity dependence of charm loop amplitudes; (ii) conservative NP solutions to B anomalies favour a left-handed or an axial lepton coupling rather than a vector one.
{ "_oai": { "updated": "2023-03-10T21:35:09Z", "id": "oai:repo.scoap3.org:75230", "sets": [ "EPJC" ] }, "authors": [ { "affiliations": [ { "country": "Italy", "value": "INFN Sezione di Roma Tre, Via della Vasca Navale 84, Rome, 00146, Italy", "organization": "INFN Sezione di Roma Tre" } ], "surname": "Ciuchini", "email": "marco.ciuchini@roma3.infn.it", "full_name": "Ciuchini, Marco", "given_names": "Marco" }, { "affiliations": [ { "country": "Germany", "value": "Institut f\u00fcr Theoretische Teilchenphysik, Karlsruhe Institute of Technology, Karlsruhe, 76131, Germany", "organization": "Karlsruhe Institute of Technology" } ], "surname": "Fedele", "email": "marco.fedele@kit.edu", "full_name": "Fedele, Marco", "given_names": "Marco" }, { "affiliations": [ { "country": "Italy", "value": "INFN Sezione di Roma, Piazzale Aldo Moro 2, Rome, 00185, Italy", "organization": "INFN Sezione di Roma" } ], "surname": "Franco", "email": "enrico.franco@roma1.infn.it", "full_name": "Franco, Enrico", "given_names": "Enrico" }, { "affiliations": [ { "country": "Germany", "value": "Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany", "organization": "Deutsches Elektronen-Synchrotron DESY" }, { "country": "Germany", "value": "Institut f\u00fcr Physik, Humboldt-Universit\u00e4t zu Berlin, Berlin, 12489, Germany", "organization": "Humboldt-Universit\u00e4t zu Berlin" } ], "surname": "Paul", "email": "ayan.paul@desy.de", "full_name": "Paul, Ayan", "given_names": "Ayan" }, { "affiliations": [ { "country": "Italy", "value": "INFN Sezione di Roma, Piazzale Aldo Moro 2, Rome, 00185, Italy", "organization": "INFN Sezione di Roma" } ], "surname": "Silvestrini", "email": "luca.silvestrini@roma1.infn.it", "full_name": "Silvestrini, Luca", "given_names": "Luca" }, { "affiliations": [ { "country": "USA", "value": "C.N. Yang Institute for Theoretical Physics, Stony Brook University, Stony Brook, NY, 11794, USA", "organization": "Stony Brook University" } ], "surname": "Valli", "email": "mauro.valli@stonybrook.edu", "full_name": "Valli, Mauro", "given_names": "Mauro" } ], "titles": [ { "source": "Springer", "title": "Charming penguins and lepton universality violation in $$\\varvec{b \\rightarrow s \\ell ^+ \\ell ^-}$$ <math> <mrow> <mi>b</mi> <mo>\u2192</mo> <mi>s</mi> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>-</mo> </msup> </mrow> </math> decays" } ], "dois": [ { "value": "10.1140/epjc/s10052-023-11191-w" } ], "publication_info": [ { "page_end": "15", "journal_title": "European Physical Journal C", "material": "article", "journal_volume": "83", "artid": "s10052-023-11191-w", "year": 2023, "page_start": "1", "journal_issue": "1" } ], "$schema": "http://repo.scoap3.org/schemas/hep.json", "acquisition_source": { "date": "2023-03-10T21:32:20.422663", "source": "Springer", "method": "Springer", "submission_number": "b6222fd2bf8a11eda920065bd8dc6b20" }, "page_nr": [ 15 ], "license": [ { "url": "https://creativecommons.org/licenses//by/4.0", "license": "CC-BY-4.0" } ], "copyright": [ { "holder": "The Author(s)", "year": "2023" } ], "control_number": "75230", "record_creation_date": "2023-01-24T09:30:08.986961", "_files": [ { "checksum": "md5:02aa093c6862246ff667f5210b691282", "filetype": "xml", "bucket": "6a89c3ba-c9ec-4a4f-aedd-fafcc2e844a8", "version_id": "7ad0ea5a-fb7c-4d6a-bcb1-e10331aa8f39", "key": "10.1140/epjc/s10052-023-11191-w.xml", "size": 22628 }, { "checksum": "md5:dedc1a7e44b71dc17fd7cec0c1ebef1c", "filetype": "pdf/a", "bucket": "6a89c3ba-c9ec-4a4f-aedd-fafcc2e844a8", "version_id": "1c9bbe90-7234-4617-95d0-99b3a7ccf293", "key": "10.1140/epjc/s10052-023-11191-w_a.pdf", "size": 1597039 } ], "collections": [ { "primary": "European Physical Journal C" } ], "abstracts": [ { "source": "Springer", "value": "The LHCb experiment has recently presented new results on Lepton Universality Violation (LUV) in $$B \\rightarrow K^{(*)} \\ell ^+ \\ell ^-$$ <math> <mrow> <mi>B</mi> <mo>\u2192</mo> <msup> <mi>K</mi> <mrow> <mo>(</mo> <mrow></mrow> <mo>\u2217</mo> <mo>)</mo> </mrow> </msup> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>-</mo> </msup> </mrow> </math> decays involving $$K_S$$ <math> <msub> <mi>K</mi> <mi>S</mi> </msub> </math> in the final state, which strengthen the recent evidence of LUV obtained in $$B^+ \\rightarrow K^{+} \\ell ^+ \\ell ^-$$ <math> <mrow> <msup> <mi>B</mi> <mo>+</mo> </msup> <mo>\u2192</mo> <msup> <mi>K</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>-</mo> </msup> </mrow> </math> decays and the previous measurements of $$B \\rightarrow K^{*0} \\ell ^+ \\ell ^-$$ <math> <mrow> <mi>B</mi> <mo>\u2192</mo> <msup> <mi>K</mi> <mrow> <mrow></mrow> <mo>\u2217</mo> <mn>0</mn> </mrow> </msup> <msup> <mi>\u2113</mi> <mo>+</mo> </msup> <msup> <mi>\u2113</mi> <mo>-</mo> </msup> </mrow> </math> . While LUV observables in the Standard Model are theoretically clean, their predictions in New Physics scenarios are sensitive to the details of the hadronic dynamics, and in particular of the charming penguin contribution. In this work, we show how a conservative treatment of hadronic uncertainties is crucial not only to assess the significance of deviations from the Standard Model but also to obtain a conservative picture of the New Physics responsible for LUV. Adopting a very general parameterization of charming penguins, we find that: (i) current data hint at a sizable $$q^2$$ <math> <msup> <mi>q</mi> <mn>2</mn> </msup> </math> and helicity dependence of charm loop amplitudes; (ii) conservative NP solutions to B anomalies favour a left-handed or an axial lepton coupling rather than a vector one." } ], "imprints": [ { "date": "2023-01-24", "publisher": "Springer" } ] }