Searcharxiv⌕ Search

arXiv subjects

L. McLerran

Publications and source records attributed to L. McLerran.

28 records · Page 2Linked to original sources
arXiv2001

Higher Twist Corrections and Maxima for DIS on a Proton in the High Density QCD Region

We show that the ratio of different structure functions have a maximum which depends on energy. We argue, using Golec-Biernat and Wusthoff model, that these maxima are the certain functions of the saturation scale. The analysis of leading and higher twist contributions for different observables is given with the aim of determining the kinematic region where high parton density effects could be seen experimentally.

hep-ph↗
arXiv2001

The Renormalization Group Equation for the Color Glass Condensate

We present an explicit and simple form of the renormalization group equation which governs the quantum evolution of the effective theory for the Color Glass Condensate (CGC). This is a functional Fokker-Planck equation for the probability density of the color field which describes the CGC in the covariant gauge. It is equivalent to the Euclidean time evolution equation for a second quantized current-current Hamiltonian in two spatial dimensions. The quantum corrections are included in the leading log approximation, but the equation is fully non-linear with respect to the generally strong background field. In the weak field limit, it reduces to the BFKL equation, while in the general non-linear case it generates the evolution equations for Wilson-line operators previously derived by Balitsky and Kovchegov within perturbative QCD.

hep-ph↗
arXiv2000

Higher twists and maxima for DIS on nuclei in high density QCD region

We show that the ratio of different structure functions have a maximum which depends on $x_B$ and $A$. We argue that these maxima are proportional to the saturation scale. The analysis of leading and higher twist contributions for different observables is given with the aim of determining the kinematic region where high parton density effects could be seen experimentally.

hep-ph↗
arXiv1999

Two Lectures on Small x Physics and High Gluon Density

In these lectures, I shall discuss small x physics and the consequences of the high gluon density which arises as x decreases. I argue that an understanding of this problem would lead to knowledge of the high energy asymptotics of hadronic processes. The high gluon density should allow a first principles computation of these asymptotics from QCD. This physics might be experimentally probed in heavy ion colliders or in high energy electron-nuclear collisions

nucl-th↗
arXiv1997

Small x Physics and Why It's Interesting

I discuss small x physics and its implications at very high energies. At very high energy the density of partons becomes so large that much of the physics can be described using weak coupling methods in QCD. This may allow for a solution to problems such as the asymptotic nature of deep inelastic scattering at fixed momentum transfer, unitarization, and multiparticle production.

hep-ph↗
arXiv1995

The Return of The Prodigal Goldstone Boson

We propose that the mass of the $η^\prime$ meson is a particularly sensitive probe of the properties of finite energy density hadronic matter and quark gluon plasma. We argue that the mass of the $η^\prime$ excitation in hot and dense matter should be small, and therefore that the $η^\prime$ production cross section should be much increased relative to that for pp collisions. This may have observable consequences in dilepton and diphoton experiments.

hep-ph↗
arXiv1995

Non-perturbative Quarkonium Dissociation in Hadronic Matter

We calculate the dissociation rates of quarkonium ground states by tunnelling and direct thermal activation to the continuum. For hadronic matter at temperatures $T \leq 0.2$ GeV, neither of these mechanisms leads to a sufficiently large dissociation to explain the experimentally observed suppression of charmonium. Dissociation by sequential excitation to excited energy levels, although OZI-forbidden, requires further analysis.

hep-ph↗
arXiv1993

B + L Non-Conservation as a Semi-Classical Process

I discuss the problem of computing B + L violation at high energies as that of solving classical differential equations. These equations involve boundary conditions at initial and a final times which are anti-Feynman, and involve solving non-linear differential equations which are complex, even if the original Hamiltonian was real.

hep-ph↗
arXiv1992

Hydrodynamic Stability Analysis of Burning Bubbles in Electroweak Theory and in QCD

Assuming that the electroweak and QCD phase transitions are first order, upon supercooling, bubbles of the new phase appear. These bubbles grow to macroscopic sizes compared to the natural scales associated with the Compton wavelengths of particle excitations. They propagate by burning the old phase into the new phase at the surface of the bubble. We study the hydrodynamic stability of the burning and find that for the velocities of interest for cosmology in the electroweak phase transition, the shape of the bubble wall is stable under hydrodynamic perturbations. Bubbles formed in the cosmological QCD phase transition are found to be a borderline case between stability and instability.

hep-ph↗