Squeezed Fermions at Relativistic Heavy Ion Colliders

Large back-to-back correlations of observable fermion -- anti-fermion pairs are predicted to appear, if the mass of the fermions is modified in a thermalized medium. The back-to-back correlations of protons and anti-protons are experimentally observable in ultra-relativistic heavy ion collisions, similarly to the Andreev reflection of electrons off the boundary of a superconductor. While quantum statistics suppresses the probability of observing pairs of fermions with nearby momenta, the fermionic back-to-back correlations are positive and of similar strength to bosonic back-to-back correlations.Comment: LaTeX, ReVTeX 12 pages, uses epsf.sty, 2 eps figures, improved presentatio

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

Group Manifold Reduction of Dual N=1 d=10 Supergravity

We perform a group manifold reduction of the dual version of N=1 d=10 supergravity to four dimensions. The effects of the 3- and 4-form gauge fields in the resulting gauged N=4 d=4 supergravity are studied in particular. The example of the group manifold SU(2)xSU(2) is worked out in detail, and we compare for this case the four-dimensional scalar potential with gauged N=4 supergravity.Comment: 22 pages, revised section 3, typos corrected. Published versio

Back-to-Back Correlations for Finite Expanding Fireballs

Back-to-Back Correlations of particle-antiparticle pairs are related to the in-medium mass-modification and squeezing of the quanta involved. They are predicted to appear when hot and dense hadronic matter is formed in high energy nucleus-nucleus collisions. The survival and magnitude of the Back-to-Back Correlations of boson-antiboson pairs generated by in-medium mass modifications are studied here in the case of a thermalized, finite-sized, spherically symmetric expanding medium. We show that the BBC signal indeed survives the finite-time emission, as well as the expansion and flow effects, with sufficient intensity to be observed at RHIC.Comment: 24 pages, 4 figure

Substituent Effect in the Oxidation of Phenols by Peroxydisulphate Ion in Aqueous Ethanol, t-Butanol, Acetonitrile & Acetone

1070-107

Spectrum sensing methods in cognitive radio network

Cognitive radio is a capable technology, which has provided a different way to increase the efficiency of the electromagnetic spectrum utilization. CR allows unlicensed users or secondary users (SUs) to use the licensed spectrum through dynamic channel assignment strategies or spectrum access when the primary users (PUs) are in a dormant state to improve the spectrum utilization and hence avoid spectrum scarcity. For this we need intelligent spectrum sensing techniques which can detect the presence of spectrum holes and allocate them to the secondary users without interfering with the activities of the primary users. This thesis specifically investigates the Cyclo-stationary detector, the energy detector and their simulation in MATLAB to know the presence of licensed users. Energy detector is a semi blind spectrum sensing technique, which do not need any prior information about the signal to know the presence of primary users. It is simple and easy to implement, but requires high SNR conditions for optimal performance, which is in accordance with our simulation results. The poor performance of ED in low SNR conditions provides option for new spectrum sensing techniques which performs better in LOW SNR conditions. In that Sense the Cyclo-stationary detector overcomes the problem as it gives optimal performance even at low SNR conditions. The wireless microphone signal which is specified in IEEE 802.22 standard (first standard based on cognitive radio) is used as the test signal for the performance evaluation of the energy detector as well as the cyclo-stationary detector

Beneficiation of low grade chromite for preparation of charge-chrome

Low grade chromite samples from rejected dumps and over-burdens were taken for beneficiation study to produce a material suitable for charge-chrome preparation. The chromite samples with about 25% Cr2O3 in average, are ferr-uginous, but non-magnetic and contain 30-40% Fe2O2 SiO2 content is significantly low. low. Limonite, followed by laterite, is the main gangue material. In general, the fraction between 0.5 mm and 0.045 mm size is richer in Cr203 than the both +0.5 mm and —0.045 mm fraction. A process involving (i) crushing to —1 mm size, (ii) desl-iming and rejection of the slime, (iii) sieving at 0.2 mm and (iv) tabling of the — 0.2 mm fraction, has been found to be successful to produce a material with Cr203 content around 44%, raising the Cr203lFe203 ratio from 0.6 to above 2.2. The process is a low cost oriented one and the beneficiated Product satisfies the requirements for chrom-ite used for preparation of charge-chrome