Towards QCD thermodynamics using exact chiral symmetry on lattice

The thermodynamics of massless ideal gas of overlap quarks has been investigated numerically for both zero and nonzero baryon chemical potential $\mu$. While the parameter M has been shown to be irrelevant in the continuum limit, it is shown numerically that the continuum limit can be reached with relatively coarser lattices for certain range of M. Numerical limitation of the existing method of introduction of chemical potential in the overlap formalism is discussed. We have also studied the energy density of free domain wall fermions in the absence of $\mu$ and estimated the extent of lattice in the fifth dimension $L_5$ for which the overlap results are recovered. Interestingly, this value of $L_5$ is also minimum for the same range of M found in the overlap case.Comment: 5 pages, 4 figures, to appear in the proceedings of the 20th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions: Quark Matter 2008 (QM2008

Thermodynamics of free Domain Wall fermions

Studying various thermodynamic quantities for the free domain wall fermions for both finite and infinite fifth dimensional extent N_5, we find that the lattice corrections are minimum for $N_T\geq10$ for both energy density and susceptibility, for its irrelevant parameter M in the range 1.45-1.50. The correction terms are, however, quite large for small lattice sizes of $N_T\leq8$. We propose modifications of the domain wall operator, as well as the overlap operator, to reduce the finite cut-off effects to within 10% of the continuum results of the thermodynamic quantities for the currently used N_T=6-8 lattices. Incorporating chemical potential, we show that \mu^2 divergences are absent for a large class of such domain wall fermion actions although the chiral symmetry is broken for $\mu\neq0$.Comment: 11 pages, 15 figures include

A faster method of computation of lattice quark number susceptibilities

We compute the quark number susceptibilities in two flavor QCD for staggered fermions by adding the chemical potential as a Lagrange multiplier for the point-split number density term. Since lesser number of quark propagators are required at any order, this method leads to faster computations. We propose a subtraction procedure to remove the inherent undesired lattice terms and check that it works well by comparing our results with the existing ones where the elimination of these terms is analytically guaranteed. We also show that the ratios of susceptibilities are robust, opening a door for better estimates of location of the QCD critical point through the computation of the tenth and twelfth order baryon number susceptibilities without significant additional computational overload.Comment: 10 pages, 12 figure

Anomalies at finite density and chiral fermions

Using perturbation theory in the Euclidean (imaginary time) formalism as well as the non-perturbative Fujikawa method, we verify that the chiral anomaly equation remains unaffected in the presence of nonzero chemical potential, $\mu$. We extend our considerations to fermions with exact chiral symmetry on the lattice and discuss the consequences for the recent Bloch-Wettig proposal for the Dirac operator at finite chemical potential. We propose a new simpler method of incorporating $\mu$ and compare it with the Bloch-Wettig idea.Comment: 12 pages, 3 figures,some typos corrected, a better proof for the \mu independence of anomaly is given in section IIB, v4: the published versio

Occultation of compact radio sources by the ion tail of Halley's Comet

Enhancements of scintillations of the compact radio sources PKS 2314+03 and 1827-360 were observed at 103 MHz and 408 MHz during 18-21 December 1985 and on 29 March 1986, respectively, when the plasma tail of Halley's Comet swept across them. At 103 MHz the RMS plasma density variation along the tail was 10 and 3.3/cu cm at 0.12 AU and 0.18 AU, respectively, as measured from the comet's position. At 408 MHz it was 1.9/cu cm at 0.036 AU. Comparison of results of these two sets of observations is presented

Receding the entrainment of concomitant Ultrafines by MGS in Lead Concentrate of Rajpura - Dariba Concentrator

Due to the fine dissemination and complex mineralogy the Rajpu ra-Dariba (RD) lead --inc ore poses special problems in concentration by corrventional froth flotation. In order to achieve the desired metallurgical results 'Multi Gravity Separator, a twin drum system, has recently been installed in the lead circuit of RD concentrator. Open and closed trial tests were conducted, without sacrificing the economic metal tt•ith substantial abatement of ultrafine card fine srliceuus and graphite matter in lead concentrate. The metallurgical alludes achieved are (i) over 85% -400 mesh fines are separated in the form of MGS tails whereas 53% -400 mesh are obtained in MGS concentrate from the feed(lead rougher concentrate) 77% -400 mesh with 52% Pb, I% Gr. C and 2.5% ISM in respective Wt. %distribution i.e., 47.3 and 3, (ii) tails are characterised br- >93% ultrafine of <20 microns particles encompass 21 % Pb, 8% Gr: C and 39% ISM with respective Wt. % distribution i.e., 32. 93, 83% in -400 mesh fr-action, resulting in effective rejection of Gr. C and ISM, (iii)conventional lead concentrate consists of 28% +400 mesh material only with all the assorted fines and ultrafines. Mine ralogically, it is established that composite bigger particles of sulphide gangue and graphite are the main contributor. for silica and graphite in MGS concentrate. Over 39% by vol. fines are alienated as MGS tails, in the form of free sulphide, gangue and graphite minerals. Installation of MGS in lead circuit, confirms the significant reduction of Gr:C and ISM in particular to high GMS_feed rnix in lead concentrate in comparison to lead concentrate by conventional route

Primary Amoebic (Naegleria fowleri) Meningoencephalitis Presenting as Status Epilepticus

Primary amebic meningoencephalitis (PAM) is a rare entity. Usual presenting features are fever, headache and seizures with meningeal signs and this disease carries high mortality rate. We present a case report of PAM presenting as status epilepticus

Groundwater externalities of surface irrigation transfers under National River Linking Project: Polavaram – Vijayawada link

River basin managementRiver basin developmentDevelopment projectsWater transferIrrigation canalsGroundwater irrigationTube well irrigationRiceSurface irrigationCrop managementSoil salinityWaterlogging