Saturation Physics and Deuteron--Gold Collisions at RHIC

We present a review of parton saturation/Color Glass Condensate physics in the context of deuteron-gold ($d+Au$) collisions at RHIC. Color Glass Condensate physics is a universal description of all high energy hadronic and nuclear interactions. It comprises classical (McLerran-Venugopalan model and Glauber-Mueller rescatterings) and quantum evolution (JIMWLK and BK equations) effects both in small-$x$ hadronic and nuclear wave functions and in the high energy scattering processes. Proton-nucleus (or $d+A$) collisions present a unique opportunity to study Color Glass Condensate predictions, since many relevant observables in proton-nucleus collisions are reasonably well-understood theoretically in the Color Glass Condensate approach. In this article we review the basics of saturation/Color Glass Condensate physics and reproduce derivations of many important observables in proton (deuteron)--nucleus collisions. We compare the predictions of Color Glass physics to the data generated by $d+Au$ experiments at RHIC and observe an agreement between the data and the theory, indicating that Color Glass Condensate has probably been discovered at RHIC. We point out further experimental measurements which need to be carried out to test the discovery.Comment: 113 pages, 65 figures, minor changes, version accepted for publication in Progress in Particle and Nuclear Physic

Vector potential versus colour charge density in low-x evolution

We reconsider the evolution equations for multigluon correlators derived in hep-ph/9709432. We show how to derive these equations directly in terms of vector potentials (or colour field strength) avoiding the introduction of the concept of colour charge density in the intermediate steps. The two step procedure of deriving the evolution of the charge density correlators followed by the solution of classical equations for the vector potentials is shown to be consistent with direct derivation of evolution for vector potentials. In the process we correct some computational errors of hep-ph/9709432 and present the corrected evolution equations which have a somewhat simpler appearance.Comment: 15 pages, 1 figure, changes made referee report, to be published in Phys. Rev

Computationally-efficient stochastic cluster dynamics method for modeling damage accumulation in irradiated materials

An improved version of a recently developed stochastic cluster dynamics (SCD) method {[}Marian, J. and Bulatov, V. V., {\it J. Nucl. Mater.} \textbf{415} (2014) 84-95{]} is introduced as an alternative to rate theory (RT) methods for solving coupled ordinary differential equation (ODE) systems for irradiation damage simulations. SCD circumvents by design the curse of dimensionality of the variable space that renders traditional ODE-based RT approaches inefficient when handling complex defect population comprised of multiple (more than two) defect species. Several improvements introduced here enable efficient and accurate simulations of irradiated materials up to realistic (high) damage doses characteristic of next-generation nuclear systems. The first improvement is a procedure for efficiently updating the defect reaction-network and event selection in the context of a dynamically expanding reaction-network. Next is a novel implementation of the $\tau$-leaping method that speeds up SCD simulations by advancing the state of the reaction network in large time increments when appropriate. Lastly, a volume rescaling procedure is introduced to control the computational complexity of the expanding reaction-network through occasional reductions of the defect population while maintaining accurate statistics. The enhanced SCD method is then applied to model defect cluster accumulation in iron thin films subjected to triple ion-beam ($\text{Fe}^{3+}$, $\text{He}^{+}$ and $$\text{H\ensuremath{{}^{+}}}$$) irradiations, for which standard RT or spatially-resolved kinetic Monte Carlo simulations are prohibitively expensive

Symplectic approach to lightcone QCD

We develop a symplectic method of quantization of lightcone QCD. We find that boundary gauge fields are crucial for a consistent and complete quantization. By applying the symplectic Faddeev-Jackiw method, we very carefully remove unphysical degrees of freedom and obtain the true phase space and the complete Hamiltonian. The result is important for the high energy QCD evolution and for a further extension of the JIMWLK equation, for which we find the second-order correction. Finally, we make an important note about a peculiarity of four space-time dimensions. In additional, our method sheds new light on the lightcone quantization of a scalar field.Comment: 24 pages, new title; final versio

Hezekiah Niles and the British, 1811-1815

Hezekiah Niles was born in 1777 in Chester County, Pennsylvania, where his parents had fled for safety before the Battle of Brandywine. After the period of danger passed, the Niles family once more took up their residence in Wilmington, Delaware. Niles spent his boyhood days here and apparently received most of his education in the Friends School. The fact that his father had been disowned by the Quaker congregation casts some doubt upon the place of the youth\u27s education. His course of study was typical of the best in that time -- a thorough knowledge of the three R\u27s and the classics

A study of participation in the Eastern Massachusetts Chapter of National Association of Social Workers

Thesis (M.S.)--Boston Universit

Forward Quark Jets from Protons Shattering the Colored Glass

We consider the single-inclusive minijet cross section in pA at forward rapidity within the Color Glass Condensate model of high energy collisions. We show that the nucleus appears black to the incident quarks except for very large impact parameters. A markedly flatter p_t distribution as compared to QCD in the dilute perturbative limit is predicted for transverse momenta about the saturation scale, which could be as large as Q_s^2 ~ 10 GeV^2 for a gold nucleus boosted to rapidity ~10 (as at the BNL-RHIC).Comment: 9 pages, no figure