Related papers: Gluon Fragmentation to Gluonium
The geometric clustering of partons in the transverse plane of nuclear collisions leads for increasing A or sqrt(s) to percolation. In the resulting condensate, the partons are deconfined but not yet in thermal equilibrium. We discuss…
A future Electron-Ion Collider will enable the gluon contributions to the gravitational form factors of the proton to be constrained experimentally for the first time. Here, the first calculation of these form factors from lattice Quantum…
This study presents new insights into gluon transverse momentum distributions through nonextensive statistical mechanics, addressing their implications for QCD phenomenology. The saturation physics and scaling laws present in high energy…
QCD suggests that gluons in the nucleon play an important role in {\it so-called} ``the proton spin problem''. In this talk, the behavior of the polarized gluon distribution in the nucleon is discussed by using the positivity condition of…
We report on recent calculations of the medium-induced gluon radiation off hard partons. The employed path-integral formalism reduces in limiting cases to the main ``jet quenching'' results of the existing literature. Moreover, it describes…
We discuss the impact of recent high-statistics RHIC data on the determination of the gluon polarization in the proton in the context of a global QCD analysis of polarized parton distributions. We find clear evidence for a non-vanishing…
The momentum spectrum and the polarization of charginos and neutralinos in squark decays are affected by gluon radiation in the decay process \tilde{q} \to q \tilde{\chi} (g). We determine these corrections and study their impact on the…
The analyses of large transverse momentum charmonium production at the Tevatron have shown that fragmentation of gluons is an important production mechanism. We study large-$p_T$ charmonium production in $pp$ collisions at the LHC, and find…
We study the polarization and dispersion properties of gluons moving within a weakly magnetized background at one-loop order. To this end, we show two alternative derivations of the charged fermion propagator in the weak field expansion and…
There is considerable freedom in setting boundary conditions to perturbation theory at $t=\pm\infty$. The standard PQED and PQCD expansions are based on the (empty) perturbative vacuum. Since the true QCD ground state is expected to have a…
The early idea that a non-perturbative gluon condensate affects the spectrum of heavy quarks is revisited in the light of modern simulation techniques. We evaluate the low lying spectrum of bound states of two heavy quarks for large…
We describe a new approach to heavy-quark fragmentation which is based on a resummed perturbative calculation and parametrization of power corrections, concentrating on the z -> 1 limit, where the heavy meson carries a large fraction of the…
We investigate the dissociation of a heavy meson in the medium composed of light quarks and gluons. In the quark-gluon plasma, the dissociation length of the heavy meson becomes short as the temperature or quark chemical potential…
The phase between three-gluon and one-photon amplitudes in psi(2S) and psi(3770) decays is analyzed.
The radiative energy loss of fast partons traveling through the quark-gluon plasma (QGP) is commonly studied within perturbative QCD (pQCD). Nonperturbative (NP) effects, which are expected to become important near the critical temperature,…
We discuss diffractive dissociation of gluons into heavy quark pairs. The particular mechanism is similar to the diffractive dissociation of virtual photons into quarks, which drives diffractive deep inelastic production of charm in the…
We compute gluon and quark propagators in 2-colour QCD at large baryon chemical potential mu. The gluon propagator is found to be antiscreened in the superfluid, confined phase and screened in the large-mu, deconfined phase. We present the…
The gluon distribution of a nucleon propagating through a nucleus can change depending on how far the penetration depth is. It is a nonperturbative process that we describe by an evolution equation. The kernel of the integral equation is to…
The short-distance coefficients for the color-octet 3S1 term in the fragmentation function for a gluon to split into heavy quarkonium states is calculated to order alpha_s^2. The gauge-invariant definition of the fragmentation function by…
Searches for new physics using muons are reviewed. Particular attention is paid to muon number non-conserving processes, like the decay muon-->e+gamma and muon-electron conversion in muonic atoms. Also, experimental determinations and…