arXiv subjects

C. A. Garcia Canal

Publications and source records attributed to C. A. Garcia Canal.

24 records · Page 2Linked to original sources

arXiv1998

LPM effect and dielectric suppression in air showers

An analysis of the influence of the Landau-Migdal-Pomeranchuck (LPM) effect on the development of air showers initiated by astroparticles, is presented. By means of computer simulations using algorithms that emulate Migdal's theory, including also the so-called dielectric suppression, we study the behaviour of the relevant observables in the case of ultra high energy primaries. We find that the LPM effect can significantly modify the development of high energy electromagnetic showers.

astro-ph↗

arXiv1997

On Charge Quantization and Abelian Gauge Horizontal Symmetries

Under the assumption that there exists a local gauge horizontal symmetry $G_H$ wich allows only for a top quark mass at tree level, we look for the constraints that charge quatization and the family structure of the standard model imposes on that symmetry.

hep-ph↗

arXiv1995

Factorization in Semi-Inclusive Polarized Deep Inelastic Scattering

We calculate and analize the ${\cal{O}}(α_s)$ one-particle inclusive cross section in polarized deep inelastic lepton-hadron scattering, using dimensional regularization and the HVBM prescription for $γ_5$. We discuss the factorization of all the collinear singularities related to the process, particularly those which are absorbed in the redefinition of the spin dependent analogue of the recently introduced fracture functions. This is done in the usual $\overline{MS}$ scheme and in another one, called $\overline{MS_p}$, which factorizes soft contributions and guarantees the axial current (non)conservation properties.

hep-ph↗

arXiv1995

Scale Dependence of Polarized DIS Asymmetries

We compare the $Q^{2}$ dependence of the polarized deep inelastic scattering proton asymmetry, driven by the leading order Altarelli Parisi evolution equations, to those arising from fixed order $α_{s}$ and $α_{s}^{2}$ approximations. It is shown that the evolution effects associated with gluons, which are not properly taken into account by the leading order approximation, cannot be neglected in the analysis of the most recent experimental data.

hep-ph↗

arXiv1995

A Method to Determine the Tau Neutrino Helicity Using Polarized Taus

A method is presented to extract the tau neutrino helicity, or equivalently, the chirality parameter $γ_{\mathrm{VA}}$, independent of any tau polarization which may be present. The method is thus well-suited to measurements using taus produced from the $Z^0$ and is complementary to analyses using tau correlations since it provides the sign of the chirality parameter which is otherwise unavailable without recourse to lower energy experiments where taus are unpolarized. Results of Monte Carlo studies and comments regarding the use of the technique in experiments are also included.

hep-ph↗

arXiv1994

Polarised parton distributions

We analyze spin dependent parton distributions consistent with the most recent measurements of the spin dependent deep inelastic scattering structure functions and obtained in the framework of the spin dilution model. Predictions for the doubly polarised proton-proton Drell-Yan asymmetry, for the high $p_{T}$ photon production mechanism and $J/Ψ$ excitation are calculated using these distributions and are shown to be particularly adequate to unveil the polarisation of partons in the proton.

hep-ph↗