Applying the method of light-cone sum rules with photon distribution amplitudes, we compute the subleading-power correction to the radiative leptonic B → γℓν decay from the twist-two hadronic photon contribution at next-to-leading order in QCD; and further evaluate the higher-twist “resolved photon” corrections at leading order in α s , up to twist-four accuracy. QCD factorization for the vacuum-to-photon correlation function with an interpolating current for the B-meson is established explicitly at leading power in Λ/m b employing the evanescent operator approach. Resummation of the parametrically large logarithms of m b 2/Λ2 entering the hard function of the leading-twist factorization formula is achieved by solving the QCD evolution equation for the light-ray tensor operator at two loops. The leading-twist hadronic photon effect turns out to preserve the symmetry relation between the two B → γ form factors due to the helicity conservation, however, the higher-twist hadronic photon corrections can yield symmetry-breaking effect already at tree level in QCD. Using the conformal expansion of photon distribution amplitudes with the non-perturbative parameters estimated from QCD sum rules, the twist-two hadronic photon contribution can give rise to approximately 30% correction to the leading-power “direct photon” effect computed from the perturbative QCD factorization approach. In contrast, the subleading-power corrections from the higher-twist two-particle and three-particle photon distribution amplitudes are estimated to be of $$ \mathcal{O}\left(3\sim 5\%\right) $$ with the light-cone sum rule approach. We further predict the partial branching fractions of B → γℓν with a photon-energy cut E γ ≥ E cut, which are of interest for determining the inverse moment of the leading-twist B-meson distribution amplitude thanks to the forthcoming high-luminosity Belle II experiment at KEK.
{ "license": [ { "url": "https://creativecommons.org/licenses/by/3.0", "license": "CC-BY-3.0" } ], "copyright": [ { "material": "Article", "holder": "The Author(s)", "year": "2018" } ], "control_number": "40473", "_oai": { "updated": "2018-11-20T10:14:40Z", "id": "oai:repo.scoap3.org:40473", "sets": [ "JHEP" ] }, "authors": [ { "affiliations": [ { "country": "China", "value": "School of Physics, Nankai University, Weijin Road 94, Tianjin, 300071, China", "organization": "Nankai University" }, { "country": "Austria", "value": "Fakult\u00e4t f\u00fcr Physik, Universit\u00e4t Wien, Boltzmanngasse 5, Vienna, 1090, Austria", "organization": "Universit\u00e4t Wien" } ], "surname": "Wang", "email": "wangyuming@nankai.edu.cn", "full_name": "Wang, Yu-Ming", "given_names": "Yu-Ming" }, { "affiliations": [ { "country": "China", "value": "College of Information Science and Engineering, Ocean University of China, Songling Road 238, Qingdao, Shandong, 266100, P.R. China", "organization": "Ocean University of China" } ], "surname": "Shen", "email": "shenylmeteor@ouc.edu.cn", "full_name": "Shen, Yue-Long", "given_names": "Yue-Long" } ], "_files": [ { "checksum": "md5:45b863daf5852fd081a8c9539cb6b7f9", "filetype": "xml", "bucket": "5b593aa4-3f13-4e78-805a-8767a73c273d", "version_id": "b9b5de7e-2cf3-4615-ab21-17cc172fc871", "key": "10.1007/JHEP05(2018)184.xml", "size": 13235 }, { "checksum": "md5:bf9771dbc1c56e907810828d983d3167", "filetype": "pdf/a", "bucket": "5b593aa4-3f13-4e78-805a-8767a73c273d", "version_id": "9112ccff-0e28-470b-a439-e8db5eb00c4b", "key": "10.1007/JHEP05(2018)184_a.pdf", "size": 889563 } ], "record_creation_date": "2018-05-30T08:22:06.741999", "titles": [ { "source": "Springer", "title": "Subleading-power corrections to the radiative leptonic B \u2192 \u03b3\u2113\u03bd decay in QCD" } ], "collections": [ { "primary": "Journal of High Energy Physics" } ], "dois": [ { "value": "10.1007/JHEP05(2018)184" } ], "publication_info": [ { "page_end": "36", "journal_title": "Journal of High Energy Physics", "material": "article", "journal_volume": "2018", "year": 2018, "page_start": "1", "journal_issue": "5" } ], "$schema": "http://repo.scoap3.org/schemas/hep.json", "abstracts": [ { "source": "Springer", "value": "Applying the method of light-cone sum rules with photon distribution amplitudes, we compute the subleading-power correction to the radiative leptonic B \u2192 \u03b3\u2113\u03bd decay from the twist-two hadronic photon contribution at next-to-leading order in QCD; and further evaluate the higher-twist \u201cresolved photon\u201d corrections at leading order in \u03b1 s , up to twist-four accuracy. QCD factorization for the vacuum-to-photon correlation function with an interpolating current for the B-meson is established explicitly at leading power in \u039b/m b employing the evanescent operator approach. Resummation of the parametrically large logarithms of m b 2/\u039b2 entering the hard function of the leading-twist factorization formula is achieved by solving the QCD evolution equation for the light-ray tensor operator at two loops. The leading-twist hadronic photon effect turns out to preserve the symmetry relation between the two B \u2192 \u03b3 form factors due to the helicity conservation, however, the higher-twist hadronic photon corrections can yield symmetry-breaking effect already at tree level in QCD. Using the conformal expansion of photon distribution amplitudes with the non-perturbative parameters estimated from QCD sum rules, the twist-two hadronic photon contribution can give rise to approximately 30% correction to the leading-power \u201cdirect photon\u201d effect computed from the perturbative QCD factorization approach. In contrast, the subleading-power corrections from the higher-twist two-particle and three-particle photon distribution amplitudes are estimated to be of <math><mi>O</mi><mfenced><mrow><mn>3</mn><mo>\u223c</mo><mn>5</mn><mo>%</mo></mrow></mfenced></math> $$ \\mathcal{O}\\left(3\\sim 5\\%\\right) $$ with the light-cone sum rule approach. We further predict the partial branching fractions of B \u2192 \u03b3\u2113\u03bd with a photon-energy cut E \u03b3 \u2265 E cut, which are of interest for determining the inverse moment of the leading-twist B-meson distribution amplitude thanks to the forthcoming high-luminosity Belle II experiment at KEK." } ], "imprints": [ { "date": "2018-05-29", "publisher": "Springer" } ], "acquisition_source": { "date": "2018-11-20T10:15:11.764392", "source": "Springer", "method": "Springer", "submission_number": "9e1fd546eca411e89d1402163e01809a" } }