Related papers: Two Lectures on Small x Physics and High Gluon Den…
This is a talk, given at Diffraction'2000, Sept. 2 - 7, Centraro, Italy. In this talk, we present the arguments, that a new QCD regime - gluon saturation, has been reached at HERA.
We present a general, model independent argument demonstrating that gluons produced in high energy hadronic collision are necessarily correlated in rapidity and also in the emission angle. The strength of the correlation depends on the…
We investigate the gluon distribution in a proton at very low $x$, both integrated and transverse momentum dependent, using the Laplace transform technique. By accounting for leading and main next-to-leading contributions, we derive compact…
Two complementary approaches to DIS at low $x$ and low $Q^2$ are presented. In the first case we apply a model containig two Pomeron trajectories. In the second case we determine the gluon density in the semiclassical treatment at…
Relativistic heavy ion physics studies the phenomena that occur when a very large (in units of QCD scale $\Lambda_{\rm QCD}$) amount of energy is deposited into a large (in units of $\Lambda^{-3}_{\rm QCD}$) volume, creating an extended in…
An overview of DIS 2003 is given with a focus on small-x physics and the interrelationship between deep inelastic scattering and heavy ion physics which furnishes much of the basic information for understanding high-density QCD matter. In…
We study quantum fluctuations of the nucleon's parton densities by combining QCD factorization for hard processes with the notion of cross section fluctuations in soft diffraction. The fluctuations of the small-x gluon density are related…
The properties of the quark-gluon medium observed in high energy nucleus-nucleus collisions are discussed. The main experimental facts about these collisions are briefly described and compared with data about proton-proton collisions. Both…
We show estimates for shadowing of gluons at small values of $x$, appropriate to RHIC and LHC experiments using a new evolution equation which takes into account the effects of gluon recombination to all orders in gluon density. We show…
Results on collisions of $^{16}$O nuclei performed at the Relativistic Heavy Ion Collider (RHIC) have been presented for the first time at Quark Matter 2023 by the STAR collaboration. $^{16}$O+$^{16}$O collisions are also expected to take…
Deep-inelastic scattering at small x is a new field of QCD phenomenology which HERA experiments started to explore. The data show the feature expected by the perturbative Regge asymptotics. We describe the parton picture of structure…
Decoding the internal structure of the proton is a fundamental challenge in physics. Historically, any new discovery about the proton has fuelled advances in several scientific fields. We have reported that gluons inside the proton…
The phenomenology of gluon saturation at small parton momentum fraction, Bjorken-x, in the proton and in the nucleus is introduced. The experimentally-accessible kinematic domains at the nucleus-nucleus colliders RHIC and LHC are discussed.…
With the advent of very powerful particle accelerators, such as RHIC and the LHC, it becomes possible to study QCD in high energy collisions, in which the gluon content of the proton or nucleus is probed and its density becomes often large…
Partons are defined as the quanta in a Fock space description of a hadron. Gluon saturation is described in the Weizs\"{a}cker-Williams approximation for a large nucleus. The elements of DGLAP and BFKL evolution are given with the BFKL…
These lectures describe some of the latest data on particle production in high-energy collisions and compare them with theoretical calculations and models based on QCD. The main topics covered are: fragmentation functions and factorization,…
Quark-gluon dynamics within protons and high-energy radiation phenomena in the universe are typically regarded as two entirely distinct fields. This paper aims to demonstrate that gluon condensation (GC) may serve as a direct bridge between…
In this proceeding, I review what we have learned, and what we will be able to learn, about low-$x$ physics from proton-nucleus ($pA$) collisions at RHIC and the LHC, and how this complements future Electron-Ion Collider (EIC) measurements.…
We present experimental evidences for the existence of a semi-hard scale in light hadrons. This includes the suppression of gluon radiation that is seen in high mass hadron diffraction; the weak energy dependence of hadronic total cross…
A brief historical review is made of the hadron-hadron (hh) total cross section and hadron-nucleus absorption cross section measurements, made mainly at high energy proton synchrotrons. Then I shall discuss low p_tprocesses, including…