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Muon electron scattering experiments such as the proposed MUonE experiment, offer an opportunity for an improved measurement of the Leading Order hadronic running of $\alpha$, denoted $\Delta \alpha_{\rm{had}}$. Such a measurement could be…

High Energy Physics - Phenomenology · Physics 2019-09-04 Ulrich Schubert , Ciaran Williams

We compute corrections of order $\alpha_s^3$ to the decay $b \to c \ell \bar\nu$ taking into account massive charm quarks. In the on-shell scheme large three-loop corrections are found. However, in the kinetic scheme the three-loop…

High Energy Physics - Phenomenology · Physics 2021-07-16 Matteo Fael , Kay Schönwald , Matthias Steinhauser

We exploit theoretical results on the meson spectrum within the framework of a Bethe-Salpeter (BS) formalism adjusted for QCD, in order to extract an ``experimental'' coupling \alpha_s^{exp}(Q^2) below 1 GeV by comparison with the data. Our…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. Baldicchi , A. V. Nesterenko , G. M. Prosperi , D. V. Shirkov , C. Simolo

Bottom-up holographic models of QCD, inspired by the AdS/CFT correspondence, have shown a remarkable degree of phenomenological success. However, they rely on a number of bold assumptions. We investigate the reliability of one of the key…

High Energy Physics - Phenomenology · Physics 2010-03-16 Aleksey Cherman , Thomas D. Cohen , Elizabeth S. Werbos

We study the decuplet baryon magnetic moments in a QCD-based quark model beyond quenched approximation. Our approach for unquenching the theory is based on the heavy baryon perturbation theory in which the axial couplings for baryon - meson…

High Energy Physics - Phenomenology · Physics 2009-10-31 Phuoc Ha

Perturbative QCD results in the MSbar scheme can be dramatically improved by switching to a scheme that accounts for the dominant power law dependence on the factorization scale in the operator product expansion. We introduce the ``MSR…

High Energy Physics - Phenomenology · Physics 2014-11-20 Andre H. Hoang , Ambar Jain , Ignazio Scimemi , Iain W. Stewart

We computed the static potential and Wilson loops to $O(\alpha^2)$ in perturbation theory for different lattice quark and gluon actions. In general, we find short distance lattice data to be well described by ``boosted perturbation…

High Energy Physics - Lattice · Physics 2015-06-25 G. S. Bali , P. Boyle , C. T. H. Davies

We re-evaluate the prompt atmospheric neutrino flux, using the measured charm cross sections at RHIC and the Large Hadron Collider to constrain perturbative QCD parameters such as the factorization and renormalization scales, as well as…

High Energy Physics - Phenomenology · Physics 2015-06-23 Atri Bhattacharya , Rikard Enberg , Mary Hall Reno , Ina Sarcevic , Anna Stasto

We study the conformal window of QCD using perturbation theory, starting from the perturbative upper edge and going down as much as we can towards the strongly coupled regime. We do so by exploiting the available five-loop computation of…

High Energy Physics - Theory · Physics 2024-12-25 Lorenzo Di Pietro , Marco Serone

The study of mesons and baryons which contain at least one charm quark is referred to as open charm physics. It offers the possibility to study up-type quark transitions. Since the $c$ quark can not be treated in any mass limit, theoretical…

High Energy Physics - Experiment · Physics 2017-06-06 Peter Weidenkaff

We study the generalized charm susceptibilities in 2+1 flavor QCD on the lattice at several lattice spacings. We show that, below the chiral crossover, these susceptibilities are well described by the hadron resonance gas (HRG) model if…

High Energy Physics - Lattice · Physics 2025-09-03 Olaf Kaczmarek , Frithjof Karsch , Peter Petreczky , Christian Schmidt , Sipaz Sharma

Measurements by the Belle Collaboration of the exclusive production of two charmonia in e^+ e^- annihilation differ substantially from theoretical predictions. Till now, no conclusive explanation for this remarkable discrepancy has been…

High Energy Physics - Phenomenology · Physics 2009-11-10 Daekyoung Kang , Jong-Wan Lee , Jungil Lee , Taewon Kim , Pyungwon Ko

In contrast to perturbative QCD, the analytic QCD models have running coupling whose analytic properties correctly mirror those of spacelike observables. The discontinuity (spectral) function of such running coupling is expected to agree…

High Energy Physics - Phenomenology · Physics 2012-07-04 César Ayala , Carlos Contreras , Gorazd Cvetič

We predict the charm and bottom quark nuclear modification factors using weakly coupled pQCD and strongly coupled AdS/CFT drag methods. The log(pT/M_Q)/pT dependence of pQCD loss and the momentum independence of drag loss lead to different…

Nuclear Theory · Physics 2008-11-26 W. A. Horowitz

Physical quantities in QCD do not depend upon $\alpha_s(Q)$. There is no way to measure $\alpha_s(Q)$ experimentally. If those statements sound shocking, please read on. They are actually well-known facts, though ones that are constantly…

High Energy Physics - Phenomenology · Physics 2024-09-04 P. M. Stevenson

Baryon chiral perturbation theory (BChPT), as an effective field theory of low-energy quantum chromodynamics (QCD), has played and is still playing an important role in our understanding of non-perturbative strong interaction phenomena. In…

Nuclear Theory · Physics 2013-06-11 Lisheng Geng

After a short status report on chiral perturbation theory, I review recent progress in determining some of the low-energy couplings by matching the effective theory to QCD. Consequences for K_{l3} decays and for the extraction of the CKM…

High Energy Physics - Phenomenology · Physics 2009-11-11 G. Ecker

The successive perturbative estimates of the pressure of QCD at high temperature T show no sign of convergence, unless the coupling constant g is unrealistically small. Exploiting known results of an effective field theory which separates…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. -P. Blaizot , E. Iancu , A. Rebhan

We make a systematic investigation on the double charm decays of $B_c$ meson, by employing the perturbative QCD approach based on $k_T$ factorization. It is found that the non-factorizable emission diagrams are not negligible in these…

High Energy Physics - Phenomenology · Physics 2013-05-30 Zhou Rui , Zou Zhitian , Cai-Dian Lu

Precise extractions of $\alpha_s$ from $\tau\to {\rm (hadrons)}+\nu_\tau$ and from $e^+e^-\to {\rm (hadrons)}$ below the charm threshold rely on finite energy sum rules (FESRs) where the experimental side is given by integrated spectral…

High Energy Physics - Phenomenology · Physics 2020-04-15 D. Boito , F. Oliani
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