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Related papers: $\alpha_s(\mu)$ from $M_{\chi_{0c(0b)}}-M_{\eta_{c…

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Correlations between the QCD coupling \alpha_s, the gluon condensate < \alpha_s G^2 >, and the c,b-quark running masses m_c,b in the MS-scheme are explicitly studied (for the first time) from the (axial-)vector and (pseudo)scalar charmonium…

High Energy Physics - Phenomenology · Physics 2018-12-04 Stephan Narison

I present a more refined analysis of the mass-splittings between the different heavy quarkonia states, using {\it new double ratios} of exponential moments of different two-point functions. Then, I test the validity of the $1/m$-expansion,…

High Energy Physics - Phenomenology · Physics 2016-09-06 Stephan Narison

We report results of our recent works [1,2] where we where the correlations between the c,b-quark running masses{m}_{c,b}, the gluon condensate<\alpha_s G^2> and the QCD coupling \alpha_s in the MS-scheme from an analysis of the charmonium…

High Energy Physics - Phenomenology · Physics 2023-08-08 Stephan Narison

We present a new QCD sum rule with high sensitivity to the continuum regions of charm and bottom quark pair production. Combining this sum rule with existing ones yields very stable results for the MS-bar quark masses, m_c(m_c) and…

High Energy Physics - Phenomenology · Physics 2008-11-26 Jens Erler , Mingxing Luo

Using the recent {\it world average} $\alpha_s(M^2_Z)= 0.118 \pm 0.006$, we give the {\it first direct extraction} from the $\Psi$ and $\Upsilon$ data of the values of the {\it running heavy quark masses} within QCD spectral sum rules to…

High Energy Physics - Phenomenology · Physics 2011-01-27 S. Narison

Measurements of $\alpha_s$, the coupling strength of the Strong Interaction between quarks and gluons, are summarised and an updated value of the world average of $\alpha_s (M_Z)$ is derived. Building up on previous reviews, special…

High Energy Physics - Phenomenology · Physics 2009-12-04 Siegfried Bethke

New double ratios of exponential moments of different two-point functions, which are less sensitive to the heavy quark mass and to the continuum effects than the commonly used ratio of moments, are presented for a more refined analysis of…

High Energy Physics - Phenomenology · Physics 2011-07-19 Stephan Narison

The measurement of the eta_b mass, together with a QCD result for the hyperfine splitting E_{HFS}=M_{Upsilon(1S)}-M_{eta_b}, allows us to determine the strong coupling constant alpha_s at a low energy scale. The result…

High Energy Physics - Phenomenology · Physics 2011-02-25 Pietro Colangelo , Pietro Santorelli , Egidio Scrimieri

We perform an extraction of alpha_s based on sum rules involving isovector hadronic tau decay data. The particular sum rules employed are constructed specifically to suppress contributions associated with poorly known higher dimension…

High Energy Physics - Phenomenology · Physics 2009-06-07 K. Maltman , T. Yavin

Determinations of the strong coupling strength, $\alpha_s$, are summarised and a new world average value of $\alpha_s (M_Z)$ is determined, using a new method of pre-averaging results within classes of measurements like hadronic $\tau$…

High Energy Physics - Experiment · Physics 2015-06-11 Siegfried Bethke

The mass of the bottom quark (both the pole mass $M_b$ and the $\MSb$ mass $m_b$) and the strong coupling constant $\alpha_s$ have been determined from QCD moment sum rules for the $\Upsilon$ system. In the pole-mass scheme large…

High Energy Physics - Phenomenology · Physics 2009-10-30 M. Jamin , A. Pich

The QCD sum rules for moments of production cross section of $b \overline b$ states in $e^+\,e^-$ annihilation are extremely sensitive to the values of $m_b$ and $\alpha_s$ for moments of large order $n$. This enables one to extract from…

High Energy Physics - Phenomenology · Physics 2015-06-25 M. B. Voloshin

We summarize recent results obtained in [1] on the running m_{c,b}(m_{c,b}) in the MS scheme and f_{D_(s), B_(s)} using QCD spectral sum rules (QSSR) known to N2LO PT series, including all dimension-six NP condensate contributions in the…

High Energy Physics - Phenomenology · Physics 2015-06-11 Stephan Narison

The mass of the bottom quark and the strong coupling constant alpha_s are determined from QCD moment sum rules for the Upsilon system. Two analyses are performed using both the pole mass M_b as well as the mass m_b in the $\MSb$ scheme. In…

High Energy Physics - Phenomenology · Physics 2008-11-26 Matthias Jamin , Antonio Pich

The current world-average of the strong coupling at the Z pole mass, $\alpha_s(m^2_{Z}) = 0.1181 \pm 0.0013$, is obtained from a comparison of perturbative QCD calculations computed, at least, at next-to-next-to-leading-order accuracy, to a…

High Energy Physics - Phenomenology · Physics 2016-06-29 David d'Enterria

QCD running coupling constant $\alpha_s(m_c)$ and $\alpha_s(m_b)$ are determined from heavy quarkonia $c\overline{c}$ and $b\overline{b}$ decays. The decay rates of $V\rightarrow 3g$ and $V\rightarrow e^+ e^-$ for $V=J/\psi$ and $\Upsilon$…

High Energy Physics - Phenomenology · Physics 2011-01-27 K. T. Chao , H. W. Huang , Y. Q. Liu

We extend our earlier lattice-QCD analysis of heavy-quark correlators to smaller lattice spacings and larger masses to obtain new values for the c mass and QCD coupling, and, for the first time, values for the b mass:…

High Energy Physics - Lattice · Physics 2014-11-20 C. McNeile , C. T. H. Davies , E. Follana , K. Hornbostel , G. P. Lepage

The current phenomenological determinations of $\alpha_s(M_\tau)$ and $\alpha_s(M_Z)$ are shown to be only marginally consistent with the QCD evolution of the strong coupling constant between $M_Z$ and $M_\tau$. This motivates a revised…

High Energy Physics - Phenomenology · Physics 2007-05-23 T. G. Steele , V. Elias

Threshold-state elementary particle lifetimes exhibit a scaling in powers of alpha = e^2/hslash*c, and a reciprocal electron-based 1/alpha scaling in particle masses that extends over two powers of 1/alpha. The m(e)/alpha coupling generates…

High Energy Physics - Phenomenology · Physics 2007-05-23 Malcolm H. Mac Gregor

We present an evaluation of heavy quarkonium states (bottomium and charmonium) from first principles. We use tree-level QCD (including relativistic corrections) and the full one-loop potential; nonperturbative effects are taken into account…

High Energy Physics - Phenomenology · Physics 2009-10-22 S. Titard , F. F. Yndurain
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