Baryon Operators and Baryon Spectroscopy

The issues involved in a determination of the baryon resonance spectrum in lattice QCD are discussed. The variational method is introduced and the need to construct a sufficient basis of interpolating operators is emphasised. The construction of baryon operators using group-theory techniques is outlined. We find that the use both of quark-field smearing and link-field smearing in the operators is essential firstly to reduce the coupling of operators to high-frequency modes and secondly to reduce the gauge-field fluctuations in correlators. We conclude with a status report of our current investigation of baryon spectroscopy.Comment: Invited talk at Workshop on Computational Hadron Physics, Cyprus, Sept. 14-17, 200

Statistical theory of spectra: Statistical moments as descriptors in the theory of molecular similarity

Statistical moments of the intensity distributions are used as molecular descriptors. They are used as a basis for defining similarity distances between two model spectra. Parameters which carry the information derived from the comparison of shapes of the spectra and are related to the number of properties taken into account, are defined.Comment: Poster presented at the 3rd NEXT-Sigma-Phi Conference, Crete, Aug.2005, revtex, 13 pages including 6 figure

My Tortuous Pathway Through Mathematical Chemistry and QSAR Research With Memories of Some Personal Interactions and Collaborations With Professors Milan Randić and Mircea Diudea

This article describes my more than four decades of not so straightforward journey through mathematical chemistry and QSAR research with descriptions of some valuable personal interactions and collaborations with Professors Milan Randić and Mircea Diudea. This work is licensed under a Creative Commons Attribution 4.0 International License

A new study of shower age distribution in near vertical showers by EAS air shower array

The air shower array has been developed since it started operation in 1931. The array covering an area of 900 sq m now incorporates 21 particle density sampling detectors around two muon magnetic spectrographs. The air showers are detected in the size range 10 to the 4th power to 10 to the 6th power particles. A total of 11000 showers has so far been detected. Average values of shower age have been obtained in various shower size ranges to study the dependence of shower age on shower size. The core distance dependence of shower age parameter has also been analyzed for presentation

Superradiant scattering from a hydrodynamic vortex

We show that sound waves scattered from a hydrodynamic vortex may be amplified. Such superradiant scattering follows from the physical analogy between spinning black holes and hydrodynamic vortices. However a sonic horizon analogous to the black hole event horizon does not exist unless the vortex possesses a central drain, which is challenging to produce experimentally. In the astrophysical domain, superradiance can occur even in the absence of an event horizon: we show that in the hydrodynamic analogue, a drain is not required and a vortex scatters sound superradiantly. Possible experimental realization in dilute gas Bose-Einstein condensates is discussed.Comment: 10 pages, 1 figur

A new configuration of dual stator induction generator employing series and shunt capacitors

Doubly-fed induction generators are suitable for systems having limited speed range as the overall control can be carried out by fractionally-rated converters. However, brushes and slip-rings used in these generators reduce system reliability and demand greater maintenance. Dual stator winding induction generator(DSWIG), being brushless, removes this limitation. Two distributed windings are embedded in the stator and the rotor is squirrel-cage. One of the windings is interfaced to an uncontrolled rectifier and the other to a fractionally rated PWM converter. Uncontrolled rectifier degrades the power quality within the generation system. At the same time, reactive power demand in induction generators increases with loading. This work deals with design and control of a standalone dc system based on DSWIG where a combination of passive tuned filter and series capacitor is utilised to address the voltage regulation and power quality issue. Simulation results using MATLAB/Simulink and experimental results (obtained from a laboratory prototype) have been presented, compared and discussed to demonstrate the effectiveness of the proposed alternative

Occurrence of Streptomyces aurantiacus in Mangroves of Bhitarkanika

Thirteen strains of Streptomyces were isolated from phyllosphere of nine mangrove tree species found in Bhitarkanika mangrove ecosystem of Orissa. According to physiological, biochemical data, all 13 of the isolates were taxonomically identified to the genus Streptomyces as aurantiacus species. All strains are grayish, spirals and forming amorphous colony. Almost all utilized araginose, produced H2S, resistant towards rifampicin and penicillin, urea except few strains. However, they exhibited different extracellular activity like phosphate solubilization, lipase and L asparaginase production. This is a unique report from this mangrove ecosystem as far as Streptomyces occurrence is concerned