Quark Number Susceptibilities & The Wroblewski Parameter

The Wroblewski parameter is a convenient indicator of strangeness production and can be employed to monitor a signal of quark-gluon plasma production : enhancement of strangeness production. It has been shown to be about a factor two higher in heavy ion collisions than in hadronic collisions. Using a method proposed by us earlier, we obtained lattice QCD results for the Wroblewski parameter from our simulations of QCD with two light quarks both below and above the chiral transition. Our first principles based and parameter free result compare well with the A-A data from SPS and RHIC.Comment: 5 pages, Plenary talk by R.V.G. at Hard Probes 2004, Ericeira, Portugal, Nov.4-10, 2004; Reference adde

The Wroblewski Parameter from Lattice QCD

Enhancement of strangeness production has since long been proposed as a promising signal of quark-gluon plasma production. A convenient indicator for it is the Wroblewski parameter which has been shown to be about a factor two higher in heavy ion collisions. Using a method proposed by us earlier, we obtained lattice QCD results for the Wroblewski parameter from our simulations of QCD with two light quarks both below and above the chiral transition. Our first principles based and parameter free result compare well with the A-A data.Comment: 5 pages, 5 figures, To appear in the proceedings of the seventeenth international conference on Ultra-Relativistic Nucleus-Nucleus Collisions (Quark Matter 2004), Oakland, US

The speed of sound and specific heat in the QCD plasma: hydrodynamics, fluctuations and conformal symmetry

We report the continuum limits of the speed of sound, c_s, and the specific heat at constant volume, c_v, in quenched QCD at temperatures of 2Tc and 3Tc. At these temperatures, c_s is within 2-sigma of the ideal gas value, whereas c_v differs significantly from the ideal gas. However, both are compatible with results expected in a theory with conformal symmetry. We investigate effective measures of conformal symmetry in the high temperature phase of QCD.Comment: Table II has been changed to show the contrubutions of the terms containing covariances clearly. Typos correcte

The scalar does not decay at finite temperatures

We investigate medium effects on mesonic screening lengths for QCD with 2-flavours of dynamical staggered quarks on lattices with cutoff a=1/6T. Denoting the cross-over temperature by $T_c$, we vary the temperature T from 0.89$T_c$ to 1.92$T_c$, spanning both the hadronic and quark gluon plasma phases. While chiral symmetry restoration in the vector channel appears to take place near $T_c$, it is seen in the scalar channel only above 1.33 $T_c$. Varying spatial lattice sizes, we find very little volume dependence in our results at 0.94 $T_c$. We discuss the stability of the scalar meson at these temperatures.Comment: Talk presented at The XXVIII International Symposium on Lattice Field Theory, Lattice2010, June 14-19, 2010, Villasimius, Ital

Taylor expansions in chemical potential

Properties of QCD at finite chemical potential are extracted using Taylor series expansions. The continuum limits of lattice results are presented. The result of expanding the free energy density, ie, the pressure, to 6th order in the expansion is shown. The Taylor coefficients of the chiral condensate are also shown. Relations between various Taylor coefficients are demonstrated. All this information is utilised to remove various lattice artifacts from the determination of the Wroblewski parameter in strangeness production.Comment: for proceedings of "Finite Density QCD at Nara

Towards A Competitive Manufacturing Sector

The Indian manufacturing sector has grown at an impressive average rate of 9.5 per cent annually since 2003-04. Its sustained growth is crucial for generating employment opportunities needed to absorb the rapidly expanding workforce. In this context, this paper reviews the current state of the sector and focuses on determinants of its competitiveness. The paper finds that Indian manufacturing sector exhibits a great deal of regional variation and a marked dualism between the organized and the unorganized segments in terms of both productivity and wage levels. The level of labour absorption in the organized manufacturing sector has been weak as reflected in the declining labour intensity in this sector. This does not augur well for achieving inclusive growth. We also find that although there have been significant changes in the composition of exports in the last 20 years; India is still a very small player at the global level, especially in knowledge intensive and advanced technology products. Finally, the paper explores Indias potential for transforming itself into a hub of mass manufacturing. We find that the main constraints in doing so have been the low level of R&D, relative lack of skilled personnel and relatively low FDI levels.manufacturing, competitiveness, mass manufacturing

Susceptibilities and screening masses in two flavor QCD

We studied QCD with two flavors of dynamical staggered quarks at finite temperature, with a bare sea quark mass of about 17 MeV. We report investigations of baryon, isospin, charge and strangeness susceptibilities, as well as screening masses obtained from correlators of local and one-link separated meson operators. These were studied as functions of valence quark mass at several temperatures. Our results for susceptibilities deviate significantly from ideal gas values, and even more from the weak coupling series. We also report the first measurement of off-diagonal quark number susceptibilities below the transition temperature, Tc, where they are the main contribution to charge fluctuations. We present evidence for a close connection between the susceptibilities and the screening masses.Comment: 15 pp, 4 fig