Precise determination of as from relativistic quarkonium sum rules. BOITO, Diogo Rodrigues; MATEU, Vicent.
Abstract: We determine the strong coupling as(mZ) from dimensionless ratios of roots of moments of the charm- and bottom-quark vector and charm pseudo-scalar correlators, dubbed R(X,n)q=(M(X,n)q)1/n/(M(X,n+1)q)1/n+1, with X=V,P, as well as from the 0-th moment of the charm pseudo-scalar correlator, M(P,0)c. In the quantities we use, the mass dependence is very weak, entering only logarithmically, starting at O??(a(2)s). We carefully study all sources of uncertainties, paying special attention to truncation errors, and making sure that order-by-order convergence is maintained by our choice of renormalization scale variation. In the computation of the experimental uncertainty for the moment ratios, the correlations among individual moments are properly taken into account. Additionally, in the perturbative contributions to experimental vector-current moments, as(mZ) is kept as a free parameter such that our extraction of the strong coupling is unbiased and based only on experimental data. The most precise extraction of as from vector correlators comes from the ratio of the charm-quark moments R(V,2)c and reads as(mZ) = 0.1168±0.0019, as we have recently discussed in a companion letter. From bottom moments, using the ratio R(V,2)c, we find as (mZ) = 0.1186±0.0048. Our results from the lattice pseudo-scalar charm correlator agree with the central values of previous determinations, but have larger uncertainties due to our more conservative study of the perturbative error. Averaging the results obtained from various lattice inputs for the n = 0 moment we find as(mZ) = 0.1177±0.0020. Combining experimental and lattice information on charm correlators into a single fit we obtain as(mZ) = 0.1170±0.0014, which is the main result of this article.
Journal of High Energy Physics
v. 2020, n. 3, p. 094-1-094-35 - Ano: 2020
Fator de Impacto: 5,833
@article={002993726,author = {BOITO, Diogo Rodrigues; MATEU, Vicent.},title={Precise determination of as from relativistic quarkonium sum rules},journal={Journal of High Energy Physics},note={v. 2020, n. 3, p. 094-1-094-35},year={2020}}
Utilizamos cookies neste site para melhor experiência de navegação. Ao acessar o site, você concorda com a nossa política de uso de cookies. Mais informações sobre nossa Política de Privacidade.
This website uses cookies to improve your experience while you navigate through the website. Out of these, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. We also use third-party cookies that help us analyze and understand how you use this website. These cookies will be stored in your browser only with your consent. You also have the option to opt-out of these cookies. But opting out of some of these cookies may affect your browsing experience.
Necessary cookies are absolutely essential for the website to function properly. These cookies ensure basic functionalities and security features of the website, anonymously.
Cookie
Duração
Descrição
cookielawinfo-checkbox-analytics
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Analytics".
cookielawinfo-checkbox-functional
11 months
The cookie is set by GDPR cookie consent to record the user consent for the cookies in the category "Functional".
cookielawinfo-checkbox-necessary
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookies is used to store the user consent for the cookies in the category "Necessary".
cookielawinfo-checkbox-others
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Other.
cookielawinfo-checkbox-performance
11 months
This cookie is set by GDPR Cookie Consent plugin. The cookie is used to store the user consent for the cookies in the category "Performance".
viewed_cookie_policy
11 months
The cookie is set by the GDPR Cookie Consent plugin and is used to store whether or not user has consented to the use of cookies. It does not store any personal data.
Functional cookies help to perform certain functionalities like sharing the content of the website on social media platforms, collect feedbacks, and other third-party features.
Performance cookies are used to understand and analyze the key performance indexes of the website which helps in delivering a better user experience for the visitors.
Analytical cookies are used to understand how visitors interact with the website. These cookies help provide information on metrics the number of visitors, bounce rate, traffic source, etc.
Advertisement cookies are used to provide visitors with relevant ads and marketing campaigns. These cookies track visitors across websites and collect information to provide customized ads.
Abstract: We determine the strong coupling as(mZ) from dimensionless ratios of roots of moments of the charm- and bottom-quark vector and charm pseudo-scalar correlators, dubbed R(X,n)q=(M(X,n)q)1/n/(M(X,n+1)q)1/n+1, with X=V,P, as well as from the 0-th moment of the charm pseudo-scalar correlator, M(P,0)c. In the quantities we use, the mass dependence is very weak, entering only logarithmically, starting at O??(a(2)s). We carefully study all sources of uncertainties, paying special attention to truncation errors, and making sure that order-by-order convergence is maintained by our choice of renormalization scale variation. In the computation of the experimental uncertainty for the moment ratios, the correlations among individual moments are properly taken into account. Additionally, in the perturbative contributions to experimental vector-current moments, as(mZ) is kept as a free parameter such that our extraction of the strong coupling is unbiased and based only on experimental data. The most precise extraction of as from vector correlators comes from the ratio of the charm-quark moments R(V,2)c and reads as(mZ) = 0.1168±0.0019, as we have recently discussed in a companion letter. From bottom moments, using the ratio R(V,2)c, we find as (mZ) = 0.1186±0.0048. Our results from the lattice pseudo-scalar charm correlator agree with the central values of previous determinations, but have larger uncertainties due to our more conservative study of the perturbative error. Averaging the results obtained from various lattice inputs for the n = 0 moment we find as(mZ) = 0.1177±0.0020. Combining experimental and lattice information on charm correlators into a single fit we obtain as(mZ) = 0.1170±0.0014, which is the main result of this article.
@article={002993726,author = {BOITO, Diogo Rodrigues; MATEU, Vicent.},title={Precise determination of as from relativistic quarkonium sum rules},journal={Journal of High Energy Physics},note={v. 2020, n. 3, p. 094-1-094-35},year={2020}}