Competition between polarizations in a gas laser with a weak phase anisotropy of the resonator

Abstract

PACS. 03.65B -Foundations, theory of measurement, miscellaneous theories. PACS. 05.30 -Quantum statistical mechanics. PACS. 05.45 -Theory and models of chaotic systems.Abstract. -A simple model for the coupling of a quantum system to a macroscopic measuring device is proposed, which allows to describe continuous measurements with finite time resolution. It is used to derive a quantum map, generating the dynamics of the quantum kicked rotor under the influence of continuous measurements. Numerical experiments with this quantum map show that the incoherent back-action of the measuring device always destroys dynamical localization on a sufficiently long time scale, and renders the measured dynamics diffusive. EUROPHYSICS LETTERS

Hadronic final state predictions from CCFM: the hadron-level Monte Carlo generator Cascade

“…These terms are entirely missing from standard LL BFKL, while in CCFM they are present, but with half the correct coefficient. 2 The second consequence of the manner in which initial state radiation has been moved into the final state, is that the LDC has slightly different small-x leading logs compared to BFKL (ω ≃ 3.23ᾱ s + . .…”

QCD factorization for deep-inelastic scattering at large Bjorken xB∼1−O(ΛQCD/Q)<

“…The resulting exponential evolution can be regarded as the evolution of the jet function from scale Q 2 to µ 2 I . The parton distribution q N (µ I ) runs from µ 2 I to a certain factorization scale µ 2 F using the DGLAP evolution [15]. This running generates the logarithms from initial-state parton radiations.…”

Soft-gluon resummation for heavy quark production in charged-current Deep Inelastic Scattering

“…However, such measurements are foreseen in the current improved-luminosity run (HERA II) and at the possible future generation of HERA III experiments [5], which should also be able to investigate the proton structure functions at low Q 2 values. Structure functions are given by convolutions of short-distance, partonic coefficient functions, C(x, µ 2 F ), usually given in the MS factorization scheme, with long-distance parton distribution functions f (x, µ 2 F ), whose dependence on the factorization scale µ F is ruled by the Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations [6,7]. The next-to-leading order (NLO) MS coefficient functions for charm production in CC DIS present terms which get arbitrarily large once the incoming quark energy fraction z in qW * → c(g) approaches unity.…”