Part of the D - dimensional Spiked harmonic oscillator spectra

The pseudoperturbative shifted - l expansion technique PSLET [5,20] is generalized for states with arbitrary number of nodal zeros. Interdimensional degeneracies, emerging from the isomorphism between angular momentum and dimensionality of the central force Schrodinger equation, are used to construct part of the D - dimensional spiked harmonic oscillator bound - states. PSLET results are found to compare excellenly with those from direct numerical integration and generalized variational methods [1,2].Comment: Latex file, 20 pages, to appear in J. Phys. A: Math. & Ge

Surface Tension at Finite Tempearture in the MIT Bag Model

At $T = 0$ the surface tension $\sigma ^{1/3}$ in the MIT bag model for a single hadron is known to be negligible as compared to the bag pressure $B^{1/4}$. We show that at finite temperature it has a substantial value of 50 - 70 MeV which also differ from hadron to hadron. We also find that the dynamics of the Quark-Gluon Plasma is such that the creation of hybrids $(s\bar{s}g)$ with massive quarks will predominate over the creation of $(s\bar{s})$ mesons.Comment: Substantial changes in the revised version and a new author included, 13 pages in Latex and one figur

Can Van Hove singularities be observed in relativistic heavy-ion collisions ?

Based on general arguments the in-medium quark propagator in a quark-gluon plasma leads to a quark dispersion relation consisting of two branches, of which one exhibits a minimum at some finite momentum. This results in a vanishing group velocity for collective quark modes. Important quantities such as the production rate of low mass lepton pairs and mesonic correlators depend inversely on this group velocity. Therefore these quantities, which follow from self energy diagrams containing a quark loop, are strongly affected by Van Hove singularities (peaks and gaps). If these sharp structures could be observed in relativistic heavy-ion collisions it would reveal the physical picture of the QGP as a gas of quasiparticles.Comment: 12 pages including nine figures and style files, invited talk given at the ICPAQGP-2001, November 26-30, 2001, Jaipur, Indi

Bound - states for truncated Coulomb potentials

The pseudoperturbative shifted - $l$ expansion technique PSLET is generalized for states with arbitrary number of nodal zeros. Bound- states energy eigenvalues for two truncated coulombic potentials are calculated using PSLET. In contrast with shifted large-N expansion technique, PSLET results compare excellently with those from direct numerical integration.Comment: TEX file, 22 pages. To appear in J. Phys. A: Math. & Ge

Gyromagnetic ratio of rapidly rotating compact stars in general relativity

We numerically calculate equilibrium configurations of uniformly rotating and charged neutron stars, in the case of insulating material and neglecting the electromagnetic forces acting on the equilibrium of the fluid. This allows us to study the behaviour of the gyromagnetic ratio for those objects, when varying rotation rate and equation of state for the matter. Under the assumption of low charge and incompressible fluid, we find that the gyromagnetic ratio is directly proportional to the compaction parameter M/R of the star, and very little dependent on its angular velocity. Nevertheless, it seems impossible to have g=2 for these models with low charge-to-mass ratio, where matter consists of a perfect fluid and where the collapse limit is never reached.Comment: 11 pages, 6 figures, accepted for publication in Classical and Quantum Gravit

Analisis Perbandingan Geokimia Granit dan Sedimen Dasar Laut di Pulau Singkep Bagian Timur, Provinsi Kepulauan Riau

Hasil analisis kimia secara umum menunjukkan kesamaan antara granit dan sedimen permukaan dasar laut. Perbedaan hanya pada dua unsur, yaitu Al2O3 dan Fe2O3; kandungan Al2O3 pada granit antara 12,63 - 15,58% dan Fe2O3 antara 1,26 - 1,78%, sedangkan sedimen permukaan dasar laut Al2O3 berkisar antara 2,10 - 3,29% dan Fe2O3 antara 7,57 - 12,88%. Hasil analisis pada Diagram Harker menunjukkan penyebaran granit dan sedimen dasar laut membentuk pola searah, mengiindikasikan pola ko-magmatik. Selanjutnya, untuk menentukan tipe granit di P. Singkep dalam kaitannya dengan kandungan timah, dua diagram SiO2 vs FeOtot/MgO dan ACF telah digunakan. Hasilnya menunjukkan bahwa granit Singkep termasuk daerah transisi antara tipe A dan tipe I&S dan tipe S yang kaya ilmenit dan berassosiasi dengan konsentrat timah. Kata kunci: granit, sedimen dasar laut, kimia, tipe I&S, tipe S, timah, Pulau Singkep Results of chemical analyses generally show the similarities between the granites and the seafloor sediments. The difference is only in the two elements, namely Al2O3 and Fe2O3; Al2O3 contents. In the granite ranges between 12.63 to 15.58% and the Fe2O3 ranges between 1.26 to 1.78%; while the seafloor sediment shows Al2O3 between 2.10 to 3, 29% and Fe2O3 between 7.57 to 12.88%. Results of the analysis on the Harker Diagram shows the distribution of the granites and the seafloors sediments form the unidirectional pattern, indicates the co-magmatic pattern. Furthermore, to determine the type of granite in Singkep Island in relation with the tin content two diagram of SiO2 vs FeOtot/MgO and ACF are used. The result shows that the Singkep granite belong to the the transition area between the A and I&S and the S type which rich of ilmenite and associated with tin concentrate. Keywords: granite, sea floor sediments, chemicals, I&S type, S type, tin, Singkep Islan

Government Fiscal Policy Impact Analysis in Infrastructure Sector and Education Sector to Improve Public Welfare

This study aimed to conduct a study and analysis of government fiscal policies related to the components of revenue (taxes) and some components of spending (education/human resources and infrastructure sectors). Issues regarding the effectiveness of the allocation of government budgets, particularly for human resources and infrastructure sectors, is an important issue that is very interesting to discuss. Especially if associated with their impact on improving people\u27s welfare. With a limited income, the government must make a choice to prioritize the education/human resources sector or infrastructure sector