012144   Khordad R;Mirhosseini B (Physics Dep, College of Sciences, Yasouj Univ, Yasouj 75914-353, Iran, Email: rezakh2025@yahoo.com) : Application of tietz potential to study optical properties of spherical quantum dots. Pramana J Phys 2015, 85(4), 723-37.

In this work, we study the optical properties of spherical quantum dots by using Tietz potential. In this regard, we have applied Nikiforov-Uvarov (NU) technique and numerically solved the Schrodinger equation to obtain energy levels and wave functions. Then, by using the density matrix method, we have derived expressions for the changes in linear and third-order nonlinear absorption coefficients and refractive index. According to the results obtained from this work, it is deduced that: (i) the total refractive index and the absorption coefficients increase and shift towards higher energies as u₀ increases; (ii) the total absorption coefficient and refractive index decrease and also shift towards lower energies as r₀ increases.

7 illus, 56 ref

012143   Kabakci S;Usta B K;Ozdemir L (Physics Dep, Sakarya Univ, 54187 Sakarya, Turkey, Email: lozdemir@sakarya.edu.tr) : M1 and E2 transitions in the ground-state configuration of atomic manganese. Pramana J Phys 2015, 85(4), 691-9.

Using the multiconfiguration Hartree-Fock approximation within the framework of the Breit-Pauli Hamiltonian (MCHF+BP) and the relativistic Hartree-Fock (HFR) approximation, we have calculated the forbidden transition (M1 and E2) parameters such as transition energies, logarithmic weighted oscillator strengths and transition probabilities between the fine-structure levels in the ground-state configuration of 3d^{54s2 for atomic manganese (Mn I, Z =25). A discussion of these calculations for manganese using MCHF+BP and HFR methods is given here.}

2 tables, 18 ref

012142   Jiang Z N;Zhang F P;Zhang X;Zhang X;Lu Q M; Zhang J X (Physics ans Electronic Engneering Dep, Guangxi Normal Univ for Nationalities, 532200, Chongzo, Guangxi, People's Republic of China) : Preparation and thermoelectric properties of the rare earths doped Ca_0.95RE_0.05MnO₃ (RE=Pr, EU and Tb) oxide materials. Indian J pure appl Phys 2015, 53(8), 530-6.

The rare earths doped Ca_0.95RE_0.05MnO₃ (RE=Pr, Eu, Tb) oxide bulk materials are fabricated and the effects of rare earths doping within low content on the thermoelectric transport properties of the CaMnO₃ oxide have been investigated. The results show that all doped oxide bulk materials are single phase with consolidated microstructure. The electrical resistivity is remarkably reduced on account of electron carrier density and mobility enhancement. The Seebeck coefficient is simultaneously reduced and the total thermal conductivity is decreased due to phonon thermal conduction confinement. The thermoelectric figure of merit ZT is improved with peak values of 0.12, 0.12 and 0.09 at 973 K for the Pr, Eu and Tb doped CaMnO₃ oxide materials, respectively, which are very much higher than that of the undoped oxide material.

5 illus, 1 table, 29 ref

012141   Jegan Antony Marcilin L (Master of Technology, Sathyabama Univ, Chennai, Tamil Nadu, Email: jegan25@hotmail.com) : Analysis of nano capacitor using scattering parameters equivalent series resistance and quality factor. Biosci Biotechnol Res Asia 2015, 12(2), 1873-82.

S Parameters or scattering parameters used in various engineering and communication systems to describe the electrical behaviour of linear networks. Basically matched loads are used instead of open or short circuit conditions to characterize linear networks. The quantities were measured in terms of power. Several electrical properties of a scattering parameters like gain, return loss, VSWR, reflection co-efficient and stability were expressed by using S-parameters. To analyse the scattering parameters the smith chart is one of the best tool for high frequency applications. This chart provides a clear and clever way to work out the complex (Real & imaginary) functions. In this paper the standard poly-propylene(PP) capacitor s-parameters are compared with the new Recycled Polyethyleneterephtalate (R-pet) nano composite capacitors. The Return loss [S11] and the insertion loss[S21],ESR, Quality factor can be analysed for the above given samples.

11 illus, 13 ref

012140   Jamil U;Abir R;De S;Mustafa M G;Srivastava D K (NO, Debraj Roy College, Golaghat, Assam-785 621, Email: ummejamil@gmail.com) : Nuclear suppression of muons at forward rapidity at relativistic heavy ion collisions. Proc Indian Natn Sci Acad 2015, 81(1), 22-7.

quarks produced in the initial stage of heavy ion collisions would traverse the quark gluon plasma, colliding with quarks and gluons and radiating gluons. In the process of collision with the quarks and gluons and also by radiation of gluons they lose energy. After their production, they may get fragmented into heavy mesons by picking up light quarks/antiquarks and in turn may decay through leptonic channels. These leptons would carry information of the initial stage of heavy ion collisions and

4 illus, 12 ref

012139   Jaiswal A (NO, Tata Institute of Fundamental Research, Mumbai-400 005, Email: amaresh.tifr@gmail.com) : Relativstic Third-order viscos hydrodynamics. Proc Indian Natn Sci Acad 2015, 81(1), 62-9.

Employing the iterative solution of Boltzmann equation in relaxation time approximation, we derive a third-order evolution equation for shear stress tensor from its kinetic definition. To this end we first obtain the non-equilibrium phase-space distribution function, f(x, p), up to second-order in gradients. The expression for df(x, p) thus obtained does not lead to the violation of the experimentally observed 1/√mT scaling of the longitudinal femtoscopic radii, as is the case with the widely used Grad's approximation, and hence is better suited for hydrodynamic modelling of relativistic heavy-ion collisions. Subsequently, we quantify the significance of this new derivation within one-dimensional scaling expansion and demonstrate that the results obtained using third-order viscous equations are in excellent agreement with the exact solution of Boltzmann equation as well as transport results.

1 illus, 28 ref

012138   Jain A;Sangeeta;Suneel Kumar (Applied Science Dep, Ludhiana College of Engineering and Technology, Katani Kalan (Ludhiana), Email: sangeeta.ar003@gmail.com) : Influence of isospin dependence of radius on fragmentation. Proc Indian Natn Sci Acad 2015, 81(1), 70-4.

Based on the Isospin dependent Quantum Molecular Dymanics (IQMD) model, we study the influence of isospin dependence of nuclear charge radii on fragmentation for the reaction of 120/50 Sn +120/50 Sn at an incident energy between 50 and 400 MeV/nucleon. Simulations have been carried out for isospin independent nuclear charge radii (proposed in liquid drop model) and isospin dependent nuclear charge radii (proposed by Royer and Rousseau) parameterizations. Our study reveals that fragmentation is influenced by the isospin dependence of nuclear charge radii and the influence varies with the mass of the fragment.

2 illus, 10 ref

012137   Jaantakun A;Jaikla W (Electronics and Telecommunication Engineering Dep, Faculty of Engineering Rajamangala Univ of Technology Isan, Khonkaen Campus, Khonkaen 40000, Thailand, Email: mr.adirek@hotmail.com) : Active-only current-mode first-order allpass filter and its application in quadrature oscillator. Indian J pure appl Phys 2015, 53(8), 557-63.

Current-mode first-order allpass filter (APF) using only the active elements has been studied in the present paper. The proposed circuit comprises two operational transconductance amplifiers (OTAs) and one operational amplifier (OA) which is suitable to future development into an integrated circuit. The pole frequency and phase response can be electronically adjusted with changing the dc bias currents of OTAs. The APF has high output impedance, which is easy to cascade in high-order filter or drive load without using a buffering device. The current-mode quadrature oscillator is included to show the usability of the proposed filter. The results of PSPICE simulation are accordant with the theoretical analysis.

14 illus, 1 table, 28 ref

012136   Hu B;Huang K;Zhang P;Zeng X A;Han Z;Yu S (College of Light Industry and Food Science, South China Univ of Technology, No. 381 Wushan Road, Guangzhou 510640, Guangdong, China, Email: shujuanyu8@gmail.com) : Pulsed electric field effects on sucrose nucleation at low supersaturation. Sugar Tech 2015, 17(1), 77-84.

Nucleation of sucrose at high supersaturation is difficult to control and the nuclei easily form aggregates, whereas at low supersaturation it is difficult to achieve nucleation using traditional methods. In order to explore a feasible method to enhance sucrose nucleation at low supersaturation, the effect of pulsed electric field (PEF) treatment on sucrose solutions at supersaturation of 1.05-1.20 was investigated. The experiments were conducted using electric field strengths of 10-30 kV cm^{-1 and flow rates of 15-50 mL min-1 in a volume of 3.0 mL. The results revealed that PEF treatment has a profound influence on sucrose nucleation at supersaturation of 1.05-1.20. Nucleation occurred at all degrees of supersaturation tested, with more nuclei formed in the more supersaturated solutions. The regression model indicated that the total nuclei number induced by PEF was proportional to supersaturation and field strength, but varied inversely with flow rate. The microstructure of the PEF-induced nuclei and a non-PEF-treated sample had a similar XRD pattern, and the PEF-induced nuclei had larger interplanar spacings, higher intensities, and greater crystallinity. PEF technology is revealed to be a promising method for sucrose nucleation at low supersaturation.}

4 illus, 2 tables, 30 ref

012135   Haque N (Theory Div, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata-700 064, Email: najmul.haque@saha.ac.in) : QCD Thermodynamics at finite temperature and finite chemical potential. Proc Indian Natn Sci Acad 2015, 81(1), 86-94.

Authors calculate thermodynamic functions viz. pressure, change in pressure due to chemical potential, quark number density of hot and dense nuclear matter at finite temperature and chemical potential using threeloop Hard Thermal Loop perturbation theory.

4 illus, 26 ref

012134   Guptaroy P (Physics Dep, Raghunathpur College, P.O. Raghunathpur-723 133, Email: gpradeepta@rediffmail.com) : On direct photon production at RHIC and LHC-energies: a theoretical approach. Proc Indian Natn Sci Acad 2015, 81(1), 28-35.

Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) have recently studied different collisions at extremely high energies and produced a sizable amount of high-precision data. In the present work, we deal with the direct photon production phenomena in p + p, d + Au Au + Au collisions at RHIC energy v √sNN = 200 GeV and in P b + P b-collisions at LHC energy v √sNN = 2.76 TeV on the basis of Sequential Chain Model (SCM). Comparisons of the model-based results with the measured data on some observables are generally found to be modestly satisfactory.

5 illus, 12 ref

012133   Greco V;Scardina F;Das S K;Plumari S (Physics and Astronomy Dep, Catania Univ, Via S. Sofia 64,95125 Catania, Italy, Email: greco@ins.infn.it) : Heavy Quark Dynamics in QGP: Boltzmann vs Langevin. Proc Indian Natn Sci Acad 2015, 81(1), 186-98.

In this manuscript we review the basic concepts related to the study of the dynamics of the heavy quarks in quark-gluon plasma created in ultra-relativistic heavy-ion collisions. We discuss the relevant physical scale as well as the difficulties of the present theoretical approach with an aim to have a self-consistent description of the experimental data at both RHIC and LHC. In the second part we challenge the assumption of brownian motion for charm quarks and compare the dynamical evolution of charm and bottom quarks in the Fokker-Planck approach with the Boltzmann Transport calculationone. We show that while for bottom the motion appears quite close to a Brownian one, this does note seems to be the case for charms quarks. In particular the solution of the full two-body collision integral shows that the anisotropic flows are large with respect to those predicted by a Langevin dynamics. We show that using isotropic cross section one may describe the suppression R_AA and elliptic flow v₂ simultaneously.

6 illus, 47 ref

012132   Ghosh S K (Centre for Condensed Matter Theory, Physics Dep, Indian Institute of Science, Bangalore-560 012, Email: sudeep@physics.iisc.ernet.in) : Spectral intensity distribution of trapped fermions. Pramana J Phys 2015, 85(4), 605-16.

To calculate static response properties of a many-body system, local density approximation (LDA) can be safely applied. But, to obtain dynamical response functions, the applicability of LDA is limited bacause dynamics of the system needs to be considered as well. To examine this in the context of cold atoms, we consider a system of non-interacting spin-1/2 fermions confined by a harmonic trapping potential. We have calculated a very important response function, the spectral intensity distribution function (SIDF), both exactly and using LDA at zero temperature and compared with each other for different dimensions, trap frequencies and momenta. The behaviour of the SIDF at a particular momentum can be explained by noting the behaviour of the density of states (DoS) of the free system (without trap) in that particular dimension. The agreement between exact and LDA SIDFs becomes better with increase in dimensions and number of particles.

4 illus, 29 ref

012131   Ghosh N C (NO, , E. K. T. P. Phase-IV, No. C-34/4 Kolkata-700 107, Email: ghosnarayan@gmail.com) : Some aspects of turbulent flow study. Indian J Theor Phys 2014, 62(1-2), 61-102.

Turbulence is seen as one of the last outstanding solved problems in classical physics. In the last century, great minds viz, Heisenberg, von Weizs "acker, Kolmogorov, Prandtl and G. I. Taylor had worked on it. Einstein put his last postdoc Bob Kraichnan on the subject of Turbulence. Rapid development of experimental and numerical techniques in this area and the growth of computing power created a lot of activities on turbulence research. Citeing turbulent associated real life phenomena here author has elaborated methodologies of turbulent study.

2 illus, 99 ref

012130   Devee M;Sarma J K (HEP Laboratory, Physics Dep, Tezpur Univ, Tezpur-784 028, Email: deveemayuri@gmail.com) : Analytical approach for the solution of the nonlinear GLR-MQ equation. Proc Indian Natn Sci Acad 2015, 81(1), 16-21.

Present paper reports the effect of nonlinear corrections to the behaviour of gluon distribution in the Gribov-Levin-Ryskin-Mueller-Qiu (GLR-MQ) approach. Here the nonlinear GLR-MQ evolution equation is solved analytically in order to determine the x and Q^{2 dependence of gluon distribution function. We observe that, the gluon distribution increases with increasing Q2 and decreasing x, which is in agreement with the perturbative QCD fits at small-x, however this particular behaviour of the gluon distribution function is tamed by the shadowing effects of gluon recombination. The obtained results of the nonlinear gluon distribution at the hot spot are compared with different global parton analysis as well as with those obtained from the solution of the modified-DGLAP (MD-DGLAP) equation and are found to be quite compatible.}

2 illus, 21 ref

012129   De S;Fries R J;Srivastava D K (NO, Bose Institute Indo-Fair Coordination Centre, Kolkata, Email: somvecc@gmail.com ) : QCD back-scattering photons in relativistic heavy ion collisions. Proc Indian Natn Sci Acad 2015, 81(1), 217-22.

High energy photons created from back-scattering of jets in quark gluon plasma are considered a valuable probe of the temperature of the plasma, and of the energy loss mechanism of quarks in the plasma. An unambiguous identification of this source through the measurement of single inclusive photon spectra and photon azimuthal anisotropies has not been conclusive so far. We proposed a method to identify this source by using the correlation with away-side trigger jet at large momentum. We estimate the spectra and nuclear modification factor of back-scattering photons in coincidence with trigger jets for the heavy ion collisions at the Large Hadron Collider (LHC) energy. We find the back-scattering photons cause a promising peak in nuclear modification factor which smears out by including trigger jet energy loss. Thus separating back-scattering photons from other photon sources using trigger jets depends crucially on our ability to estimate the initial trigger jet energy in experiment.

2 illus, 9 ref

012128   Chushnyakova M V;Gontchar I I (Physics Dep, Omsk State Technical Univ, Omsk, Russia, Email: maria.chushnyakova@gmail.com) : Oscillations of the fusion cross-sections in the <. Pramana J Phys 2015, 85(4), 653-65.

Evolution of the fusion cross-section in the ^{16O+16O reaction has been analysed. It is shown, both analytically and numerically, that in this excitation function some oscillations can be observed. These oscillations are related to the quantum character of the orbital angular momentum increase as well as to the distinct features of the 16O+16O reaction. In order to perform the numerical calculations, the fluctuation-dissipation model and the single barrier penetration model are used. It turns out that the experimental data available in the literature do not have any definite proof about the presence or absence of the oscillations. We stress, that the question still remains unanswered for more than three decades whereas during this time lapse the experimental errors for other reactions are reduced to 1-2%.}

9 illus, 26 ref

012127   Chebil W;Fouzri A;Azeza B;Sakly N;Mghaieth R; Lusson A;Sallet V (Laboratoire Physico-chimie des Materiaux; Unite de Service Commun de R, Universite de Monastir, Faculte des Sciences de Monastir, Avenue de l', 5019 Monastir, Tunisia) : Comparison of ZnO thin films on different substrates obtained by sol-gel process and deposited by spin-coating technique. Indian J pure appl Phys 2015, 53(8), 521-9.

In the present paper, zinc oxide thin films obtained by sol gel process and deposited on glass, sapphire, Si (100), Si (111) and ZnO substrates by spin-coating technique have been studied. Effects of using different substrates on the structural, morphological and optical properties have been investigated. The structural properties have been analyzed using X-ray diffraction (XRD) and the recorded patterns indicated that all the deposited films are polycrystalline with a hexagonal Wurtzite structure and exhibit preferentially oriented along the c-axis direction. The surface morphology has been examined by Scanning Electron Microscopy which revealed that the microstructure of the films strongly affected by the nature and orientation of substrate namely grain shape and size. Optical absorbance measurements have been taken using UV-Vis spectrophotometer and the calculated values of the direct band gap energy are around 3, 3.08 and 3.19 eV, for the ZnO films deposited on ZnO, sapphire c and glass substrates, respectively. Photoluminescence measurements taken at 4 K exhibit a near band edge composed by two principal's peaks situated at 3.36 and 3.31 eV and attributed to the neutral donor bound exciton (D°X) and to the deep acceptor (A°X), their intensity varied with the nature of substrate.

6 illus, 2 tables, 42 ref

012126   Chattopadhyay S;Choudhury S;Sarkar D (NO, Variable Energy Cyclotron Centre, Kolkata, Email: sub@vecc.gov.in) : Present and future QGP research in high energy heavy ion collision experiments. Proc Indian Natn Sci Acad 2015, 81(1), 321-35.

As a part of the programme to explore the matter under extreme conditions in high energy heavy ion collisions, experiments at LHC have collected data in Pb-Pb collisions at √sNN = 2.76 TeV. Results from p-p and p-Pb collisions at LHC at different centre of mass energies have been used as references to the results from Pb-Pb collisions. These results are further compared with detailed and elaborate measurements performed with Au-Au collisions at √sNN = 200 GeV at RHIC. The basic properties of the matter created at LHC have been found to be similar to that at RHIC, e.g., the matter in Pb-Pb collisions at LHC also behaves like a strongly coupled partonic liquid as inferred for the Au-Au collisions at top RHIC energy. However, with higher collision energy at LHC, a new set of probes in heavy ion collisions like jets and higher states of quarkonia open up new avenues in detailed understanding of the properties of the matter. Recent findings of the collective behaviour at p-Pb collisions at LHC however questions the existing theoretical understanding of the medium formation in p-Pb and Pb-Pb collisions. RHIC and LHC explore the high temperature and nearly zero net-baryon density region of the phase diagram, another extremes are being explored at the beam energy scan (BES) programme at RHIC and the upcoming CBM experiment at FAIR. The BES-I results demonstrate that at lower √sNN, several findings that were interpreted as the signatures of the formation of de-confined partonic matter at top RHIC energy were found to be absent. The interpretation of these results require thorough understanding of the role of baryons in the matter created at lower √sNN. The CBM experiment at FAIR aims to explore the matter created at low collision energy by the use of bulk and rare probes.

1 table, 61 ref

012125   Chattopadhyay A K;Kulkarni S V;Srinivasan R; Aditya Team (NO, Institute for Plasma Research, Bhat, Gandhinagar-382 428, Email: asim@ipr.res.in) : Second-harmonic ion cyclotron resonance heating scenarios of Aditya tokamak plasma. Pramana J Phys 2015, 85(4), 713-21.

Plasma heating with the fast magnetosonic waves in the ion cyclotron range of frequencies (ICRF) is one of the auxiliary heating schemes of Aditya tokamak. Numerical simulation of second-harmonic resonance heating scenarios in low-temperature, low-density Aditya plasma has been carried out for fast magnetosonic wave absorption in ICRF range, using full-wave ion cyclotron heating code TORIC combined with Fokker-Planck quasilinear solver SSFPQL and the results are explained. In such low-temperature, low-density plasma, ion absorption for second-harmonic resonance heating is less but significant amount of direct electron heating is observed.

6 illus, 9 ref

012124   Chatterjee S (School of Physical Science, National Institute of Science Education and Research, Bhubaneshwar-751 005, Email: chatterjee.sandeep@niser.ac.in) : Multiple freezeout. Proc Indian Natn Sci Acad 2015, 81(1), 100-6.

Effect of hadrochemistry has largely been ignored while constructing the chemical freezeout stage of the fireball evolution in heavy ion collisions. Thus, almost all models of hadron production use a single chemical freezeout surface where the yields of all hadrons get fixed together. We argue from the viewpoint of hadrochemistry that such a scheme of chemical freezeout should be replaced by a multiple freezeout scheme where mainly hadrons with zero and non-zero strangeness content freezeout separately. This is shown to improve the fits to measured hadron yields in the entire range of v √sNN from 6.27 - 2700 GeV. We also point out possible influence of the QCD critical point and crossover transition on the extracted thermal parameters.

2 illus, 1 table, 18 ref

012123   Biswas S;Roy P (NO, Rishi Bankim Chandra College, Naihati, North 24-Parganas, West Bengal, Email: anjansubhra@gmail.com) : Contribution of π-η mixing to the difference between pp and nn scattering lengths. Proc Indian Natn Sci Acad 2015, 81(1), 169-73.

Authors revisit the problem of charge symmetry violation (CSV) in nucleon-nucleon interactions due to π-η mixing driven by the neutron-proton mass difference. We construct the CSV potential and estimate the contribution to the difference between pp and nn scattering lengths.

1 illus, 16 ref

012122   Bhattacharyya R;Dey S;Ghosh S K;Maulik A;Raha S;Syam D (Center for Astroparticle Physics and Space Science, Bise Institute, Kolkata-700 091, Email: rupamoy@jcbose.ac.in) : Strangelet search at Mountain Altitude. Proc Indian Natn Sci Acad 2015, 81(1), 165-8.

Detection of strangelet is an important goal in the field of cosmic rays. It is also important for our understanding of the physics and astrophysics of strongly interacting matter. In our present work, we have used Solid State Nuclear Track Detectors (SSNTDs), which, being passive detectors, offer an alternative low cost detector option, to look for such rare events in cosmic rays. We have placed CR-39 along with Polyethylene Terephthalate (PET) to study the background radiation at mountain altitudes and variations in detector response with different environmental conditions. Observations for the present work have been made at different mountain altitudes. Some preliminary results of the study are presented here.

4 illus, 5 ref

012121   Bhattacharyya A;Das S;Ghosh S K;Raha S;Ray R; Saha K;Upadhaya S (Physics Dep, Calcutta Univ, 92, APC Road, Kolkatta-700 009, Email: saha.k09@gmail.com) : D-Measure from Polyakov-Nambu-Jona-Lasinio model. Proc Indian Natn Sci Acad 2015, 81(1), 152-7.

Authors present the first case study of the net charge fluctuations in terms of D - measure within the framework of an effective model viz. Polyakov Nambu-Jona-Lasinio model. The net charge fluctuation is obtained from the charge susceptibility computed in this model. A parameterization of the freeze-out curve in heavy-ion experiments has been used to obtain D as a function of the collision energy.

4 illus, 22 ref

012120   Bhattacharyya A;Das S;Ghosh S K;Raha S;Ray R; Saha K;Upadhaya S (Physics Dep, Calcutta Univ, 92, APC Road, Kolkata-700 009, Email: sudipa@jcbose.ac.in) : Fluctuations from Polyakov-Nambu-Jona-Lasinio model. Proc Indian Natn Sci Acad 2015, 81(1), 56-61.

We compute various orders of fluctuations of conserved charges like baryon number and charge, which are of utmost importance in the quest for the dynamical properties of the exotic matter produced in high energy heavy ion collision experiments, viz. Quark-Gluon Plasma (QGP). Alongside analysis of their behavior with temperature and chemical potentials, the study is realized under the spectrum of contrasting experimental conditions as well.

3 illus, 17 ref

012119   Bhattacharya T;Mazumder S;Abir R (NO, Variable Energy Cyclotron Centre, Kolkata, Email: trambak.bhattacharya@gmail.com) : Gluon radiation off heavy flavour jets. Proc Indian Natn Sci Acad 2015, 81(1), 228-32.

It is known that gluon bremsstrahlung emission off heavy flavor jet is suppressed in the forward direction compared to that of light quark due to the mass effect ('dead cone effect'). Most of the models that address jet quenching generally assume that a jet always travels in straight eikonal path. However, once the eikonal approximation of propagation is called off and jet is allowed to bend, additional gluons popup within the so called 'depopulated' region deluging the dead cone. This color synchrotron by color charge, once wound in an ambiance of color field, seems to be more physical for better understanding of jet quenching in hot and dense deconfined quark-gluon medium.

5 illus, 8 ref

012118   Bhattacharya A;Das S;Ghosh S K;Ray R;Samanta S (Physics Dep, Calcutta Univ, Kolkata-700 009, Email: samanta@jcbose.ac.in) : Fluctuations in excluded volume hadron resonance gas model. Proc Indian Natn Sci Acad 2015, 81(1), 51-5.

Authors present temperature (T) dependence of higher order fluctuations of conserved baryon number in Excluded Volume Hadron Resonance Gas (EVHRG) model. Products of moments, such as ratio of variance to mean (σ^{2/M), product of skewness and standard deviation (Sσ), product of kurtosis and variance (kσ2), for net-proton has been evaluated on the phenomenologically determined freeze-out curve and has been compared with the experimental data measured by STAR experiment.}

2 illus, 9 ref

012117   Atreya A;Bagchi P;Srivastava A M (Institute of Physics, Sachivalaya Marg, Bhubaneswar-751 005, Email: partha@iopb.res.in) : Novel mechanism for j/ψ disintegration in relativistic heavy ion collisions. Proc Indian Natn Sci Acad 2015, 81(1), 207-12.

In this paper we discuss the possibility of J/ψ disintegration due to the Z(3) domain walls that are expected to form in QGP medium. These domain walls give rise to localised color electric field which disintegrates J/ψ, on interaction, by changing the color composition and simultaneously exciting it to higher states of c system.

1 illus, 17 ref

012116   Ananda D B;Bhattacharya S;Das T K (NO, Indian Institute of Science Education and Research, Pune-411 008, Email: tapas@hri.res.in) : On the Realizability of relativistic acoustic geometry under a generalized perturbation scheme for axisymmetric matter flow onto black holes. Proc Indian Natn Sci Acad 2015, 81(1), 244-50.

Authors propose a novel linear perturbation scheme to study the stability properties of the stationary transonic integral solutions for axisymmetric matter flow around astrophysical black holes for the Schwarzschild as well as for rotating Rindler spacetime. We discuss the emergence of the relativistic acoustic geometry as a consequence of such stability analysis. Our work thus makes a crucial connection between two apparently non-overlapping fields of research - the accretion astrophysics and the analogue gravity phenomena.

7 ref

012115   Alhaz Uddin M;Eabad Ali M;Wali Ullah M; Bipasha R S (Mathematics Dep, Khulna Univ of Engineering and Technology, Khulna-9203, Bangladesh, Email: alhazuddin@yahoo.com) : Analytical approximate solution of fourth-order weakly non-linear differential systems based on unified KBM method with strong damping and slowly varying co-efficients. Indian J Theor Phys 2014, 62(1-2), 103-26.

An approximate analytic technique is presented for obtaining the solution of fourth-order weakly non-linear differential systems with strong damping and slowly varying co-efficients based on unified Krylov-Bogoliubov-Mitropolskii (KBM) method. The first-order approximate solutions for different initial conditions show good agreement with those of numerical solutions obtained by the fourth-order Runge-Kutta method and these are compared graphically. Also some limitations of the KBM method are discussed. An example is given for justifying the method.

4 illus, 16 ref

012114   Adak R P;Chattopadhyan S;Das S;Dubey A K; Ganti M S;Saini J;Singaraju R (Centre for Astro-particle Physics and Space Sciences, Bose Institute, Kolkata-700 091, Email: rpadak@jcbose.ac.in) : Testing of track point resolution of gas electron multiplier with pion beam at CERN SPS. Proc Indian Natn Sci Acad 2015, 81(1), 36-9.

Muon detection system using segmented and instrumented absorber has been designed for high-energy heavy-ion collision experiments to be held at GSI, Darmstadt, Germany. The muon detector system is mounted downstream of a Silicon Tracking System. The reconstructed tracks from the STS are to be matched to the hits in the GEM detector. For reconstructing track in the GEM Detector, track point resolution is an important issue. We report her first time the track point resolution of the GEM detector.

5 illus, 4 ref

011010   Uma Maheswari C;Sahadevan R (Ramanujan Institute for Advanced Study in Mathematics, Madras Univ, Chennai-600 005, Email: ramajayamsaha@yahoo.co.in) : Analytic methods to generate integrable mappings. Pramana J Phys 2015, 85(5), 807-21.

Systematic analytic methods of deriving integrable mappings from integrable nonlinear ordinary differential, differential-difference and lattice equations are presented. More specifically, we explain how to derive integrable mappings through four different techniques namely, (1) dis-cretization technique, (ii) Lax pair approach, (iii) periodic reduction of integrable nonlinear partial difference equations and (iv) construction of sufficient number of integrals of motion. The applicability of methods have been illustrated through Ricatti equation, a scalar second-order nonlinear ordinary differential equation with cubic nonlinearity, 2- and 3-coupled second-order nonlinear ordinary differential equations with cubic nonlinearity, lattice equations of Korteweg-de Vries, modified Korteweg-deVries and sine-Gordon types.

36 ref

011009   Tiwari A K;Durga Devi A;Gladwin Pradeep R; Chandrasekar V K (Centre for Nonlinear Dynamics, School of Physics, Bharathidasan Univ, Tiruchirapalli-620 024, Email: chandru25nd@gmail.com) : Isocchronous lienard-type nonlinear oscillators of arbitrary dimensions. Pramana J Phys 2015, 85(5), 789-805.

In this paper, we briefly present an overview of the recent developments made in identifying/generating systems of Lienard-type nonlinear oscillators exhibiting isochronous properties, including linear, quadratic and mixed cases and their higher-order generalizations. There exists several procedures/methods in the literature to identify/generate isochronous systems. The application of local as well as nonlocal transformations and Ω-modified Hamiltonian method in identifying and generating systems exhibiting isochronous properties of arbitrary dimensions is also discussed in detail. The identified oscillators include singular and nonsingular Hamiltonian systems and PT-symmetric systems.

48 ref

011008   Tehrani F S (Physics Dep, Semnan Univ, 35195 363 Semnan, Iran, Email: shariatmadartehrani@yahoo.com) : Transformation from amorphous to nano crystalline SiC thin films prepared by HWCVD technique without hydrogen dilution. Bull Mater Sci 2015, 38(5), 1333-8.

Silicon carbide (SiC) thin films were deposited on Si(111) by the hot wire chemical vapour deposition (HWCVD) technique using silane (SiH₄) and methane (CH₄) gases without hydrogen dilution. The effects of SiH₄ to CH₄ gas flow ratio (R) on the structural properties, chemical composition and photoluminescence (PL) properties of the films deposited at the different gas flow ratios were investigated and compared. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectra revealed a structural transition from amorphous SiC to cubic nano-crystalline SiC films with the increase in the gas flow ratio. Raman scattering confirmed the multi-phased nature of the films. Auger electron spectroscopy showed that the carbon incorporation in the film structure was strongly dependent on the gas flow ratio. A similar broad visible room-temperature PL with two peaks was observed for all SiC films. The main PL emission was correlated to the band to band transition in uniform a-SiC phase and the other lower energy emission was related to the confined a-Si : H clusters in a-SiC matrix. SiC nano-crystallites exhibit no significant contribution to the radiative recombination.

7 illus, 41 ref

011007   Tamizhmani K M (Mathematics Dep, Pondicherry Univ, Kalapet, Puducherry-605 014, Email: kmtmani54@gmail.com ) : Integrability detectors. Pramana J Phys 2015, 85(5), 823-47.

In this short review, we present some applications and historical facts about the integrability detectors: Painleve analysis, singularity confinement and algebraic entropy.

134 ref

011006   Subhashini P;munirathinam B;Krishnaiah M; Venkatesh R;Venkateshwarlu D;Ganesan V (Physics Dep, Sri Venkateswara Univ, Tirupati-517 502, Email: subhashinisvu@gmail.com) : Electronics transport and magnetoresistivity of La_0.4B0.1B0.5-xSr_{xMnO3>D(x=0.1 and 0.2).} Bull Mater Sci 2015, 38(5), 1449-55.

Electrical resistivity and magnetoresistive behaviour of bismuth-substituted lanthanum manganites La_0.4Bi_0.1Ca_0.5-xSr_xMnO₃ (x = 0.1 and 0.2) were systematically studied by varying the temperature from 2 to 300 K and the magnetic field up to 12 T. The samples were found to crystallize in rhombohedral structure and their morphology shows near-spherical nanosize crystallites. Charge ordering was observed in both the samples under zero field conditions and corresponding transition temperature T <60> CO was found to decrease with the increase of x. Resistivity measurements with magnetic field also showed suppression of magnetoresistivity (MR) with the increase of x and the maximum MR was found to be 98 and 93% for x = 0.1 and 0.2, respectively, at 10 T. In the high-temperature domain, the electronic transport was observed to be dominated by the variable range hopping mechanism for both the samples, whereas in the low-temperature domain the electrical conduction of x = 0.1 sample was observed to be contributed by various other electron scattering mechanisms.

7 illus, 3 tables, 40 ref

011005   Senthilvelan M;Chandrasekar V K;Mohanasubha R (Centre for Nonlinear Dynamics, School of Physics, Bharathidasan Univ, Tiruchirappalli-620 024, Email: velan@cnld.bdu.ac.in) : Symmetries of nonlinear ordinary differential equations the modified emden equation as a case study. Pramana J Phys 2015, 85(5), 755-87.

Lie symmetry analysis is one of the powerful tools to analyse nonlinear ordinary differential equations. We review the effectiveness of this method in terms of various symmetries. We present the method of deriving Lie point symmetries, contact symmetries, hidden symmetries, nonlocal symmetries, λ-symmetries, adjoint symmetries and telescopic vector fields of a secondorder ordinary differential equation. We also illustrate the algorithm involved in each method by considering a nonlinear oscillator equation as an example. The connections between (i) symmetries and integrating factors and (ii) symmetries and integrals are also discussed and illustrated through the same example. The interconnections between some of the above symmetries, i.e., (i) Lie point symmetries and λ-symmetries and (ii) exponential nonlocal symmetries and λ-symmetries are also discussed. The order reduction procedure is invoked to derive the general solution of the second-order equation.

1 table, 67 ref

011004   Sangeetha K;Babu R R;Ramaurthi K (Crystal Growth and Thin Film Laboratory, Physics Dep, Bharathidasan Univ, Tiruchirappalli-620 024, Email: rampap2k@yahoo.co.in) : Effect of PH on the morphology, mechanical and optical properties of L-arginine monohydrobromide monohydrate (LAHBr) single crystals. Bull Mater Sci 2015, 38(5), 1419-22.

L-arginine monohydrobromide monohydrate (LAHBr) single crystals were grown from two molar mixtures of L-arginine and HBr acid in 1 : 2 and 1 : 3 ratios. The solution pH of the above molar ratios was measured to be 7.2 and 1.8, respectively. This drastic change in pH has modified the morphology of LAHBr single crystal and influenced the mechanical stability, optical transparency, refractive index, birefringence and laser damage threshold. The decrease in pH from 7.2 to 1.8 has enhanced the optical transparency and laser damage threshold of LAHBr crystal.

3 illus, 2 table, 19 ref

011003   Rathod S G;Bhajantri R F;Ravindrachary V; Pujari P K;Nagaraja G K;Naik J;Hebbar V A;Chandrappa H (Physics Dep, Mangalore Univ, Mangalagangotri-574 199, Email: rfbhajantri@gmail.com) : Temperature dependent ionic conductivity conductivity and transport properties of LiClO₄ doped PVA modifed cellulose composites. Bull Mater Sci 2015, 38(5), 1213-21.

This paper presents the investigation on physicochemical properties and ionic conductivity of LiClO₄-doped poly(vinyl alcohol) (PVA)/modified cellulose composites. The percolative behaviour of LiClO₄ with dc conductivity (σ_dc) for different LiClO₄ weight fractions (p) related to transport dimensionality was also focused. The highest ionic conductivity of 9.79 x 10^{-6 S cm-1 was observed for 20 wt% LiClO₄ doping level at room temperature. The activation energies (E_g) were estimated using temperature-dependent conductivity, which follows the Arrhenius and Vogel-Tammann-Fulcher (VTF) relation. The dynamic fragility (f) and activation energy (E_g) vs. T_g of polymer composites using equivalence of the both Williams-Landel-Ferry (WLF) and VTF equations were also correlated. Transport properties such as travel time of ions between sites (τ_o), mobility (μ), diffusion coefficient (D) and number of transitions per unit time P(E) for normal cationic (Li+) hopping process of LiClO₄-doped PVA/mCellulose composites have been investigated using the Rice and Roth model.}

7 illus, 2 table, 31 ref

011002   Pushpa N;Kokila M K;Nagabhushana H B M;Reddy A J (Physics Dep, Bangalore Univ, Bangalore-560 056, Email: drmkkokila@gmail.com) : Red luminescence from ZnO: Cr<. Bull Mater Sci 2015, 38(5), 1359-65.

ZnO : Cr^{3+ (1 mol%) nanophosphor is synthesized by the wet chemical solution combustion method at the temperature of 400°C. Powder X-ray diffraction results confirmed that Cr3+-doped and undoped ZnO nanophosphors exhibit hexagonal wurtzite structure. The average crystallite size calculated from Scherrer's method is 25 nm for undoped and 14 nm for Cr3+-doped ZnO. The UV-visible absorption spectra shows red shift in Cr3+-doped ZnO. Photoluminescence studies of undoped ZnO show violet emission peak at 400 nm and blue emission peak at 447 nm. Cr3+-doped ZnO shows red emission peaks at 642, 694 and 746 nm, which are mainly attributed to spin forbidden transitions of 2E_g →4A_2g of Cr3+ ion in ZnO : Cr3+ nanophosphor. Thermoluminescence (TL) studies recorded at a heating rate of 6°C s-1-1 show two well-resolved glow peaks at 124 and 284°C. It is found that the TL intensity increases with the gamma irradiation dose (500 Gy-10 kGy).}

13 illus, 1 table, 32 ref

011001   Porsezian K;Vasantha Jayakantha Raja R (Physics Dep, Pondicherry Univ, Puducherry-605 014, Email: ponzsol@yahoo.com) : Soliton fission and supercontinuum generation in photonic crystal fibre for optical coherence tomography application. Pramana J Phys 2015, 85(5), 993-1007.

Authors present a practical design of novel photonic crystal fibre (PCF) to investigate the nonlinear propagation of femtosecond pulses for the application of optical coherence tomography (OCT) based on supercontinuum generation (SCG) process. In addition, this paper contains a brief introduction of the physical phenomena of soliton and SCG. Typically, here we discuss how the ultrabroadband radiation in PCF can be generated by SCG through various nonlinear effects of the fibre. To accomplish the proposed aim, we put forth liquid core PCF (LCPCF) structure filled with chloroform for OCT measurements of the eye. From the proposed design, we observe that proposed LCPCFs with liquid material exhibit significant broadened wavelength spectrum with low input pulse energy over small propagation distances for the OCT application.

11 illus, 39 ref

011000   Nakamura K;Kanna T;Sakkaravarthi K (Faculty of Physics, National Univ of Uzbekistan, Vuzgorodok, Tashkent 100174, Uzbekistan, Email: kanna_phy@bhc.edu.in) : Protocol of networks using energy sharing collisions of bright solitons. Pramana J Phys 2015, 85(5), 1009-21.

It is well known that solitons in integrable systems recover their original profiles after their mutual collisions. This is not true in the case of optical fibre arrays, governed by a set of integrable coupled nonlinear Schrodinger (CNLS) equations. We consider the Manakov- and mixed-type `two-component' CNLS systems. The most important characteristics of these systems are: (i) The polarizations of the two-component solitons are changed through their mutual collisions (Manakov system) and (ii) the energy (intensity) switching occurs through the head-on collision (mixed system). By placing the above solitons on the primary star graph (PSG), we see that soliton collisions give rise to interesting phase changes in PSG: (a) The transition in PSG from its depolarized state to polarized one; (b) a state with selectively amplified bond is generated on PSG from its homogeneous state. These results will be applicable to network protocols using optical fibre arrays.

9 illus, 23 ref

010999   Miah M I (Physics Dep, Chittagong Univ, Chittagong-4331, Bangaladesh, Email: m.miah@griffith.edu.au) : Observation of the nano effect on the SHG in moderately Cu-doped CdI_{2 thin nanocrystals.} Bull Mater Sci 2015, 38(5), 1329-32.

Nanocrystals take into account the nano-sized quantum-confined effect, where k-space bulk-like dispersion disappears and discrete excitonic-like nanolevels occur within the forbidden energy gap of the material processes. Nanocrystals of cadmium iodide both un-doped and doped with copper, synthesized and grown by the standard Bridgman method, were analysed by scanning electron microscopy for the investigation of the nano-confined effect on the optical nonlinearity. The second harmonic generation (SHG) of the crystals was measured and studied. The second-order optical susceptibilities in dependences of the size of the nanocrystals and of their copper contents within low levels were calculated. The results showed a clear increase in the SHG with the decrease in the thickness of the nanocrystals. The observed size dependence, however, demonstrates the nano-confined effect or nano-effect on the SHG, where the quantum confinement dominates the material's optical properties. A significant change in the second-order optical response with copper content of the nanocrystals was also observed. The observed results are discussed by exploring the photo-induced electron-phonon anharmonic interaction for the noncentrosymmetry of the nanocrystallite's process.

5 illus, 23 ref

010998   Majhi M;Choudhary R B;Maji P (Applied Physics Dep, Indian Schools of Mines, Dhanbad-826 004, Email: rbchec@yahoo.co.in) : CoCl₂ reinforced polymeric nanocomposites of conjugated polymer (Polyaniline) and its conductive properties. Bull Mater Sci 2015, 38(5), 1195-1203.

Polyaniline (PANI) was synthesized by chemical oxidative polymerization of aniline using ammonium persulphate as an oxidant in acidic aqueous medium. Cobalt chloride hexahydrate (CoCl₂.6H₂O)-doped PANI composite was synthesized by in-situ oxidative polymerization process by using various concentrations of CoCl₂. Its chemical, structural and morphological properties were examined by X-ray diffraction, energydispersive X-ray spectroscopy, Fourier transform infrared spectroscopy and field-emission scanning electron microscopy techniques. These results confirmed the successful formation of PANI and CoCl₂-doped PANI nanocomposites. The morphology of CoCl₂-doped PANI nanocomposite was found to be spherical in nature. The dielectric properties were examined using LCR-HITESTER in the frequency range 50 Hz-5 MHz. The optical properties were examined by UV-visible spectroscopic techniques in the wavelength range of 200-800 nm. The high dielectric properties and alternating current conductivity of the composite was studied in the temperature range 313-373 K. It was found that the synthesized polymeric nanocomposite owned fairly suitable dielectric and optical properties for its application in actuators, conductive paints and for many other purposes.

8 illus, 2 table, 35 ref

010997   Kundu A (Theory Div, Saha Institute of Nuclear Physics, Kolkata-700 064, Email: anjan.kundu@saha.ac.in) : Construction of classical and quantum integrable field models unravelling hidden possibilities. Pramana J Phys 2015, 85(5), 899-913.

Reviewing briefly the concept of classical and quantum integrable systems, we propose an alternative Lax operator approach, leading to quasi-higher-dimensional integrable model, unravelling some hidden dimensions in integrable systems. As an example, we construct a novel integrable quasi-two-dimensional NLS equation at the classical and the quantum levels with intriguing application in rogue wave modelling.

5 illus, 12 ref

010996   Konar S;Trofimov V A (Physics Dep, Birla Institute of Technology, Mesra, Ranchi-835 215, Email: skonar@bitmesra.ac.in) : Some aspects of optical spatial solitons in photorefractive media and their important applications. Pramana J Phys 2015, 85(5), 975-92.

Some important properties of photorefractive spatial solitons and their applications have been reviewed in the present paper. Using band transport model, the governing principle of photorefractive nonlinearity has been addressed and nonlinear dynamical equations of spatial solitons owing to this nonlinearity have been discussed. Mechanisms of formation of screening and photovoltaic solitons of three different configurations, i.e., bright, dark and grey varieties have been examined. Incoherently coupled vector solitons due to single and two-photon photorefractive phenomena have been highlighted. Modulation instability of a broad quasicontinuous optical beam has also been discussed. Finally possible applications have been highlighted.

3 illus, 88 ref

010995   Khare A (NO, Indian Institute of Science Education and Research (IISER), Homi Bhabha Road, Pashan, Pune-411 008, Email: khare@physics.unipune.ac.in) : PT -symmetric dimer of coupled nonlinear oscillators. Pramana J Phys 2015, 85(5), 915-28.

Authors provide a systematic analysis of a prototypical nonlinear oscillator system respecting PT-symmetry, i.e., one of them has gain and the other an equal and opposite amount of loss. We first discuss various symmetries of the model. We show that both the linear system as well as a special case of the nonlinear system can be derived from a Hamiltonian, whose structure is similar to the Pais-Uhlenbeck Hamiltonian. Exact solutions are obtained in a few special cases. We show that the system is a superintegrable system within the rotating wave approximation (RWA). We also obtain several exact solutions of these RWA equations. Further, we point out a novel superposition in the context of periodic solutions in terms of Jacobi elliptic functions that we obtain in this problem. Finally, we briefly mention numerical results about the stability of some of the solutions.

16 ref

010994   Keshavamurthy K;Eraiah B (Physics Dep, Bangalore Univ, Bangalore-560 056, Email: eraiah@rediffmail.com) : Influence of europium Eu<. Bull Mater Sci 2015, 38(5), 1381-4.

The influence of europium (Eu^{3+) ions on the optical properties of silver lead borate glasses of the _xEu₂O₃-(1 - x)Ag₂O-29PbO-70B₂O₃ (x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol%) glass system prepared by the conventional melt quenching technique and their physical and optical properties were investigated. The UV absorption spectra were recorded at room temperature in the wavelength range of 200-600 nm. From the absorption edge data, it is found that both the direct and indirect transitions and their values are ranging from 3.19 to 3.54 and 2.50 to 3.07 eV, respectively. The Urbach energy values for these glasses were found to be in the range of 0.39-0.52 eV. The refractive indices have also been evaluated with respect to different molar concentrations of Eu₂O₃ and their calculated values are ranging from 1.598 to 1.654.}

7 illus, 22 ref

010993   Kanna T;Sakkaravarthi K;Vijayajayanthi M (Physics Post Graduate and Research Dep, Bishop Heber College, Tiruchirappalli-620 017, Email: kanna_phy@bhc.edu.in) : Novel energy sharing collisions of multicomponent solitons. Pramana J Phys 2015, 85(5), 881-97.

In this paper, we discuss the fascinating energy sharing collisions of multicomponent solitons in certain incoherently coupled and coherently coupled nonlinear Schrodinger-type equations arising in the context of nonlinear optics.

7 illus, 29 ref

010992   Javed A;Sundaram I A;Chakraborty D (NO, , Defence Research and Development Loboratory, Hyderbad, Email: debasis_cfd@drdl.drdo.in) : Internal Ballistic Code for solid rocket motors using minimum distance function for grain burnback. Def Sci J 2015, 65(3), 181-8.

Computer code has been developed for internal ballistic performance evaluation of solid rocket motors, using minimum distance function (MDF) approach for prediction of geometry evolution. This method can handle any complex geometry without the need to define different geometrical shapes and their evolution as used in several existing analytical geometry evolution-based methodologies. The code is validated with both experimental results published in literature, as well as for solid rocket motors of tactical and strategic missiles and a very good match is obtained with static test results. The output of the code gives p-t (pressure-time) curve as well as the detailed parameters of the flow along the axial direction, and geometries in the form of mesh file, which can be further used as input to codes for CFD analysis.

9 illus, 2 table, 18 ref