Studies on gluon evolution and geometrical scaling in kinematic constrained unitarized BFKL equation: application to high-precision HERA DIS data

We suggest a modified form of a unitarized BFKL equation imposing the so-called kinematic constraint on the gluon evolution in multi-Regge kinematics. The underlying nonlinear effects on the gluon evolution are investigated by solving the unitarized BFKL equation analytically. We obtain an equation of the critical boundary between dilute and dense partonic system, following a new differential geometric approach and sketch a phenomenological insight on geometrical scaling. Later we illustrate the phenomenological implication of our solution for unintegrated gluon distribution $f(x,k_T^2)$ towards exploring high precision HERA DIS data by theoretical prediction of proton structure functions ($F_2$ and $F_L$) as well as double differential reduced cross section $(\sigma_r)$. The validity of our theory in the low $Q^2$ transition region is established by studying virtual photon-proton cross section in light of HERA data

Parallel magnetic field induced giant magnetoresistance in low density {\it quasi}-two dimensional layers

We provide a possible theoretical explanation for the recently observed giant positive magnetoresistance in high mobility low density {\it quasi}-two dimensional electron and hole systems. Our explanation is based on the strong coupling of the parallel field to the {\it orbital} motion arising from the {\it finite} layer thickness and the large Fermi wavelength of the {\it quasi}-two dimensional system at low carrier densities.Comment: 4 pages with 4 figures. Accepted for Publication in Physical Review Letter

Enhancing Tight Gas Recovery Through Hydraulic Fracture Treatment Design Optimization

Tight and deep unconventional gas reservoirs are becoming targets for development but the conventional approach to develop them is not feasible. In most cases, they cannot be produced economically without hydraulic fracturing. There have been much progress in the overall hydraulic fracturing procedures to stimulate tight formation, but there is still a lack in treatment-design optimization. Some of the currently available commercial software do not take into consideration several key parameters and associated realistic constraints.An integrated model to optimize hydraulic fracture treatment has been developed to enhance gas production and net present value with minimum treatment cost. This model couples with the industry experience with hydraulic fracture mechanics. Unlike commercial software, important design parameters are included. The free design variables are randomly varied during optimization. The overall hydraulic fracturing design problem is viewed as a multi-objective and multivariate system design problem, which recognizes complex interactions between a hydraulically coupled fracture geometry model, a hydrocarbon production model and an investment-return cash flow model. The integrated model has been successfully applied to a hypothetical deeper tight gas formation to demonstrate its merits. The optimum treatment design indicates a 300% increment in production over 10 years at a lower cost compared to production from non-fractured tight gas sand. This optimization scheme presents a decision support system, which provides a goal-oriented optimum design in a conflicting environment.Key words: Stimulation; Enhanced recovery; Fracture optimization; Tight gas; Treatment desig