0000000000468620
AUTHOR
A. Vairo
Momentum anisotropy effects for quarkonium in a weakly coupled quark-gluon plasma below the melting temperature
In the early stages of heavy-ion collisions, the hot QCD matter expands more longitudinally than transversely. This imbalance causes the system to become rapidly colder in the longitudinal direction, and a local momentum anisotropy appears. In this paper, we study the heavy-quarkonium spectrum in the presence of a small plasma anisotropy. We work in the framework of potential nonrelativistic QCD at finite temperature. We inspect arrangements of nonrelativistic and thermal scales complementary to those considered in the literature. In particular, we consider temperatures larger and Debye masses smaller than the binding energy, which is a temperature range relevant for presently running LHC e…
The strong coupling constant: State of the art and the decade ahead
This document provides a comprehensive summary of the state-of-the-art, challenges, and prospects in the experimental and theoretical study of the strong coupling $\alpha_s$. The current status of the seven methods presently used to determine $\alpha_s$ based on: (i) lattice QCD, (ii) hadronic $\tau$ decays, (iii) deep-inelastic scattering and parton distribution functions fits, (iv) electroweak boson decays, hadronic final-states in (v) e+e-, (vi) e-p, and (vii) p-p collisions, and (viii) quarkonia decays and masses, are reviewed. Novel $\alpha_s$ determinations are discussed, as well as the averaging method used to obtain the PDG world-average value at the reference Z boson mass scale, $\…
QCD and Strongly Coupled Gauge Theories: Challenges and Perspectives
We dedicate this document to the memory of Mikhail Polikarpov, who passed away in July 2013. Misha worked with us for decades as a convener of the “Confinement” section of the Quark Confinement and Hadron Spectrum Series. He guided and expanded the scientific discussion of that topic, inspiring and under taking new research avenues. From its initial conception, he supported the enterprise of this document and organized Sect. 8, writing the part on confinement himself. He attracted the XIth Conference on Quark Confinement and the Hadron Spectrum to St. Petersburg (September 8-12, 2014; see http://phys.spbu.ru/confxi.html). His warm and kind personality, his high sense of humor, his ideas in …