Searcharxiv⌕ Search

arXiv subjects

Antonio D. Polosa

Publications and source records attributed to Antonio D. Polosa.

25 records · Page 2Linked to original sources
arXiv2016

$χ^{\vphantom\dagger}_{c0}(3915)$ As the Lightest $c\bar c s \bar s$ State

The state $χ^{\vphantom\dagger}_{c0}(3915)$ has recently been demoted by the Particle Data Group from its previous status as the conventional $c\bar c$ $2 {}^3P_0$ state, largely due to the absence of expected $D\bar D$ decays. We propose that $χ^{\vphantom\dagger}_{c0}(3915)$ is actually the lightest $c\bar c s \bar s$ state, and calculate the spectrum of such states using the diquark model, identifying many of the observed charmoniumlike states that lack open-charm decay modes as $c\bar c s \bar s$. Among other results, we argue that $Y(4140)$ is a $J^{PC} = 1^{++}$ $c\bar c s \bar s$ state that has been not been seen in two-photon fusion largely as a consequence of the Landau-Yang theorem.

hep-ph↗
arXiv2015

A note on the fate of the Landau-Yang theorem in non-Abelian gauge theories

Using elementary considerations of Lorentz invariance, Bose symmetry and BRST invariance, we argue why the decay of a massive color-octet vector state into a pair of on-shell massless gluons is possible in a non-Abelian SU(N) Yang-Mills theory, we constrain the form of the amplitude of the process and offer a simple understanding of these results in terms of effective-action operators.

hep-ph↗
arXiv2014

Four-Quark Hadrons: an Updated Review

The past decade witnessed a remarkable proliferation of exotic charmonium-like resonances discovered at accelerators. In particular, the recently observed charged states are clearly not interpretable as q-qbar mesons. Notwithstanding the considerable advances on the experimental side, conflicting theoretical descriptions do not seem to provide a definitive picture about the nature of the so-called XYZ particles. We present here a comprehensive review about this intriguing topic, discussing both those experimental and theoretical aspects which we consider relevant to make further progress in the field. At this state of progress, XYZ phenomenology speaks in favour of the existence of compact four-quark particles (tetraquarks) and we believe that realizing this instructs us in the quest for a firm theoretical framework.

hep-ph↗
arXiv2006

Jet Shapes in Opaque Media

We present general arguments, based on medium-induced radiative energy loss, which reproduce the non-gaussian shapes of away-side di-jet azimuthal correlations found in nucleus-nucleus collisions at RHIC. A rather simple generalization of the Sudakov form factors to opaque media allowing an effective description of the experimental data is proposed.

hep-ph↗
arXiv2006

Diquark-antidiquark states with hidden or open charm

Some features and predictions of a recently proposed model based on diquark-antidiquark bound states are illustrated. Its ability in accomodating newly discovered charmed resonances around 4 GeV is discussed.

hep-ph↗
arXiv2001

B0bar decays to D(*)0 eta and D(*)0 eta'

We consider the hadronic B decays B0bar -> D0 eta, B0bar -> D*0 eta, B0bar -> D0 eta', B0bar -> D*0 eta' in the framework of a quark-flavour basis and factorization. The formalism allows to compute the decays to the eta meson and to relate them to those of the eta'. Measuring the branching ratios of these processes may shed light on the nature of the eta-eta' mixing. On the experimental side, only upper limits on the branching ratios are known at present.

hep-ph↗
arXiv1996

Finite Size Analysis of the U(1) Background Field Effective Action

We apply the finite size scaling analysis to the derivative of the density of the effective action for the lattice U(1) pure gauge theory in an external constant magnetic field. We found the presence of a continuous phase transition. Moreover, our extimate of of the critical parameters gives values consistent with those extracted from the analysis of the specific heat.

hep-lat↗