The Crystallography of Strange Quark Matter

Cold three-flavor quark matter at large (but not asymptotically large) densities may exist as a crystalline color superconductor. We explore this possibility by calculating the gap parameter Delta and free energy Omega(Delta) for possible crystal structures within a Ginzburg-Landau approximation, evaluating Omega(Delta) to order Delta^6. We develop a qualitative understanding of what makes a crystal structure stable, and find two structures with particularly large values of Delta and the condensation energy, within a factor of two of those for the CFL phase known to characterize QCD at asymptotically large densities. The robustness of these phases results in their being favored over wide ranges of density and though it also implies that the Ginzburg-Landau approximation is not quantitatively reliable, previous work suggests that it can be trusted for qualitative comparisons between crystal structures. We close with a look ahead at the calculations that remain to be done in order to make contact with observed pulsar glitches and neutron star cooling.Comment: 6 pages, 3 figures. Contribution to the proceedings of Strangeness in Quark Matter 2006, UCLA. Talk given by Rishi Sharm

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

Reply on `comment on our paper `Single two-level ion in an anharmonic-oscillator trap: Time evolution of the Q function and population inversion ''

We show here that the model Hamiltonian used in our paper for ion vibrating in a q-analog harmonic oscillator trap and interacting with a classical single-mode light field is indeed obtained by replacing the usual bosonic creation and annihilation operators of the harmonic trap model by their q-deformed counterparts. The approximations made in our paper amount to using for the ion-laser interaction in a q-analog harmonic oscillator trap, the operator F_{q}=exp{-(|\epsilon|^2}/2)}exp{i\epsilon A^{\dagger}}exp{i\epsilon A}, which is analogous to the corresponding operator for ion in a harmonic oscillator trap that is $F=exp{-(|\epsilon|^2 /2)}exp{i\epsilon a^{\dagger }}exp{i\epsilon a}$. In our article we do not claim to have diagonalized the operator, $F_q = exp{i \epsilon (A^{\dagger}+A)}$, for which the basis states |g,m> and |e,m> are not analytic vectors.Comment: Revtex, 4pages. To be Published in Physical Review A59, NO.4(April 99

Three-dimensional turbopump flowfield analysis

A program was conducted to develop a flow prediction method applicable to rocket turbopumps. The complex nature of a flowfield in turbopumps is described and examples of flowfields are discussed to illustrate that physics based models and analytical calculation procedures based on computational fluid dynamics (CFD) are needed to develop reliable design procedures for turbopumps. A CFD code developed at NASA ARC was used as the base code. The turbulence model and boundary conditions in the base code were modified, respectively, to: (1) compute transitional flows and account for extra rates of strain, e.g., rotation; and (2) compute surface heat transfer coefficients and allow computation through multistage turbomachines. Benchmark quality data from two and three-dimensional cascades were used to verify the code. The predictive capabilities of the present CFD code were demonstrated by computing the flow through a radial impeller and a multistage axial flow turbine. Results of the program indicate that the present code operated in a two-dimensional mode is a cost effective alternative to full three-dimensional calculations, and that it permits realistic predictions of unsteady loadings and losses for multistage machines

AGRO-PESTICIDES AND ANDROLOGY

The extensive use of pesticides in agricultural practices has resulted in contamination of food and food resources. A number of animal species including humans have accumulated traces of pesticides through food chain. These toxic chemicals influence the physiology of numerous non-target species including man. The effects of many pesticides have been analyzed using in vivo and in vitro techniques and degenerative changes induced by the toxic chemicals have been reported even at nanomolar concentrations. The adverse effects on the male reproductive system include direct damage of the cells or disruption of the developmental pathways directly or through endocrine modifications. Toxic pesticides are known to cause Germ cells disintegration, loss of Leydig cells, atresia in Sertoli cell, degeneration of seminiferous tubules, alternation in spermatogenesis, depletion in semen quality, teratospermia and endocrine disruption. For ensuring pesticide free food and food supplements it is recommended that biological alternative should be explored to safeguard good health of plants, animals and humans

Analysis of Genetic Divergence in Tomato (Lycopersicon esculentum Mill.)

Non-hierarchical analysis conducted on 60 genotypes of tomato (Lycopersicon esculentum Mill.) grouped the genotypes into 10 clusters. Maximum divergence within a cluster was exhibited by the cluster VIH (1.531), closely followed by cluster III (1.528) and cluster V (1.460), whereas, cluster VIII and cluster II were the most divergent from each other followed by cluster VII and cluster VIII. Promising genotypes selected were FT-5, LBR-10-2, THS-1-1, THS-2-2, T-99-1-2 and T-99-2-3 for yield per plant, fruit size index, pericarp thickness and plant height, whereas, W 55, Campbell and EC-123018 were found to be the best for average fruit weight. However, genotypes EC-170785 and Red cherry may be used to improve the number of fruits per plant and earliness

Nuclear reaction studies of unstable nuclei using relativistic mean field formalisms in conjunction with Glauber model

We study nuclear reaction cross-sections for stable and unstable projectiles and targets within Glauber model, using densities obtained from various relativistic mean field formalisms. The calculated cross-sections are compared with the experimental data in some specific cases. We also evaluate the differential scattering cross-sections at several incident energies, and observe that the results found from various densities are similar at smaller scattering angles, whereas a systematic deviation is noticed at large angles. In general, these results agree fairly well with the experimental data.Comment: 9 pages, 7 figures, submitted to PR