C. Parrinello
University of Liverpool
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by C. Parrinello.
Physical Review D | 1998
Derek B. Leinweber; Jon-Ivar Skullerud; Anthony G. Williams; C. Parrinello
The gluon propagator is calculated in quenched QCD for two different lattice sizes (
Physical Review D | 1999
Jeffrey R. Forshaw; Joannis Papavassiliou; C. Parrinello
{16}^{3}\ifmmode\times\else\texttimes\fi{}48
Physics Letters B | 1996
L. Conti; C. Parrinello; S. Petrarca; A. Vladikas
and
arXiv: High Energy Physics - Phenomenology | 1999
G. Burgio; F. Di Renzo; C. Parrinello; C. Pittori
{32}^{3}\ifmmode\times\else\texttimes\fi{}64
arXiv: High Energy Physics - Lattice | 1999
Derek B. Leinweber; C. Parrinello; Jon-Ivar Skullerud; Anthony G. Williams
) at
arXiv: High Energy Physics - Lattice | 1999
Derek B. Leinweber; C. Parrinello; Jon-Ivar Skullerud; Anthony G. Williams
\ensuremath{\beta}=6.0.
arXiv: High Energy Physics - Lattice | 1998
C. Parrinello; D.G. Richards; B. Alles; H. Panagopoulos; C. Pittori
The volume dependence of the propagator in the Landau gauge is studied. The smaller lattice is instrumental in revealing finite volume and anisotropic lattice artifacts. Methods for minimizing these artifacts are developed and applied to the larger lattice data. New structure seen in the infrared region survives these conservative cuts to the lattice data. This structure serves to rule out a number of models that have appeared in the literature. A fit to a simple analytical form capturing the momentum dependence of the nonperturbative gluon propagator is also reported.
arXiv: High Energy Physics - Lattice | 1999
G. Burgio; F. Di Renzo; C. Parrinello; C. Pittori
We argue that the massive Yang-Mills model of Kunimasa and Goto, Slavnov, and Cornwall, in which massive gauge vector bosons are introduced in a gauge-invariant way without resorting to the Higgs mechanism, may be useful for studying diffractive scattering of strongly interacting particles. We perform in this model explicit calculations of S-matrix elements between quark states, at tree level, one loop, and two loops, and discuss issues of renormalisability and unitarity. In particular, it is shown that the S-matrix element for quark scattering is renormalisable at one-loop order and is only logarithmically non-renormalisable at two loops. The discrepancies in the ultraviolet regime between the one-loop predictions of this model and those of massless QCD are discussed in detail. Also, some of the similarities and differences between the massive Yang-Mills model and theories with a Higgs mechanism are analysed at the level of the S-matrix. Finally, we briefly discuss the high-energy behaviour of the leading-order amplitude for quark-quark elastic scattering in the diffractive region. The above analysis sets up the stage for carrying out a systematic computation of the higher order corrections to the two-gluon exchange model of the Pomeron using massive gluons inside quantum loops.
arXiv: High Energy Physics - Lattice | 1997
C. Parrinello
Abstract We investigate the viability of the quasi-temporal gauge on the lattice. This is a complete gauge fixing condition that can be implemented on the lattice at a very low computational cost. As a test case, using the Clover action, we have evaluated the (gauge invariant) renormalisation constant of the non-singlet axial current, using Ward identities extracted from quark states. Our result is in reasonable but not complete agreement with previous values obtained from Ward identities both on hadronic states and on quark states in the Landau gauge. We observe large fluctuations due to lattice Gribov copies. The influence of finite volume effects is expected to be non-negligible in the case we are considering.
Physical Review D | 1999
Derek B. Leinweber; Jon-Ivar Skullerud; Anthony G. Williams; C. Parrinello
Abstract We study deviations from the perturbative asymptotic behaviour in the running QCD coupling by analysing non-perturbative measurements of αs(p) at low momenta (p ≈ GEV) as obtained from the lattice three-gluon vertex. Our exploratory study provides some evidence for power corrections to the perturbative running proportional to 1 p 2 .