A theory of product selection (a model of a NIC)

The objective of this work is to theoretically evaluate an important aspect of a Newly Industrializing Country (NICs): Korea. Namely, the behaviour of firms in Korea competing with firms in an industrialized country after all Government intervention of the former is withdrawn. This aspect is considered in the main part while a descriptive introductory part introduces the Korean economy as a NIC. We construct a simple asymmetric duopoly model where firms conjectures play an important role in deriving the Perfect Equilibrium for a two stage game. Different costs of production and first mover advantage form the basis of the asymmetry. We find that under Cournot conjectures assumption for the marketing stage and certain cost conditions, it is profitable for the incumbent firm to stay a leader and the follower to remain a follower. For some cost conditions and a credible threat at the disposal of the follower, the incumbent firm may be forced to stay a leader even though it is more profitable to became a follower. We examine possible licensing rules the leader may propose to the follower. The dominant strategy, we find, is a licence fee that is a function of the quality difference between the top quality of the market leader and the level of quality it is selling to the follower. There will be a cost to the leader in terms of a lower licence fee to prevent possible leap forgging. Once we allow for free copying, we find that the follower will copy closely the new product of the leadership. Under Bertrand conjectures assumption, we find that unless the firm with higher production cost remains the leader offering a higher quality product, it will be driven out of the market, i. e., either it has to innovate or-die

The widths of quarkonia in quark gluon plasma

Recent lattice calculations showed that the quarkonia will survive beyond the phase transition temperature, and will dissolve at different temperatures depending on the type of the quarkonium. In this work, we calculate the thermal width of the quarkonium at finite temperature before it dissolves into open heavy quarks. The input of the calculation are the parton quarkonium dissociation cross section to NLO in QCD, the quarkonium wave function in a temperature-dependent potential from lattice QCD, and a thermal distribution of partons with thermal masses. We find that for the J/psi, the total thermal width above 1.4 Tc becomes larger than 100 to 250 MeV, depending on the effective thermal masses of the quark and gluon, which we take between 400 to 600 MeV. Such a width corresponds to an effective dissociation cross section by gluons between 1.5 to 3.5 mb and by quarks 1 to 2 mb at 1.4 Tc. However, at similar temperatures, we find a much smaller thermal width and effective cross section for the upsilon.Comment: 7 pages, 13 figures, 2 tables, version to be published in Phys. Rev.

J/psi hadron interaction in vacuum and in QGP

Motivated by the recent lattice data that $J/\psi$ will survive up to 1.6$T_c$, we calculate the thermal width of $J/\psi$ at finite temperature in perturbative QCD. The inputs of the calculation are the parton quarkonium dissociation cross sections at the NLO in QCD, which were previously obtained by Song and Lee, and a gaussian charmonium wave function, whose size were fitted to an estimate by Wong by solving the schrodinger equation for charmonium in a potential extracted from the lattice at finite temperature. We find that the total thermal width above 1.4$T_c$ becomes larger than 100 to 200 MeV, depending on the effective thermal masses of the quark and gluon, which we take it to vary from 600 to 400 MeV.Comment: 4 pages, Talk at Quark Matter 200