012175   Gogoi D P;Ahmed G A;Mohanta D;Choudhury A; Stanciu G A (Physics Dep, Tezpur Univ, PO. Naapam, Assam-784 028, Email: dpgogoi@gmail.com) : Structural and optical properties of Mn doped ZnS semiconductor nanostructures. Indian J Phys 2010, 84(10), 1361-7.

Manganese doped zinc sulphide nanoparticles were fabricated by adopting an inexpensive solution growth route. Different samples were fabricated by varying Mn concentrations. UV-VIS study reveals blue-shift on the onset of absorption and hence enhancement in the optical band gap upto 0.75 eV, indicating strong quantum confinement. Photoluminescene study for all the samples display characteristic band edge peak at <126>410 nm. The broad peak <126>560-580 nm is described to Mn incorporation. Further, structural investigations were carried out by using X-Ray diffraction and transmission electron microscopy (TEM).

7 illus, 1 table, 14 ref

012174   Gedam R K;Kulkarni D K;Dhoke N V (Physics Dep, Institute of Science, Nagpur, Email: dkknag@rediffmail.com) : Structural and physical studies of naturally occurring chalcoprite in central India. Ultra Scient phys Sci 2009, 21(1), 179-84.

The study focus on the structural and physical studies of chalcopyrite (CuFeS₂.) samples in Laboratory. The sample has been characterized by X-ray diffraction technique and revealed that the sample is possesses tetragonal crystal structure with chalcopyrite structure and preferred orientation along (112) plane with the space group I 4 2d and point group 4 2m. The value of lattice parameter a and c for the sample is found to be 5.293 °A and 10.423 °A respectively. The d.c. electrical resistivity measurement have been carried out over temperature range of 300° to 800°K. The temperature dependence of electrical resistivity exhibited two activation energies. The magnetic susceptibility value is found to be 41.75 x 10^-8m³kg^-1 (S.I.unit). These values are compared with the standard data and showed that the sample is having tetragonal system structure, semiconductor behavior and paramagnetic which become ferromagnetic after applied external field.

4 illus, 2 tables, 19 ref

012173   Gaur K;Singh S (Physics Dep, K.N. Govt. P.G. College, Gyanpur, Bhadohi) : Electrical transport in V₂ZrO₅ and Mn₂ZrO₅. Ultra Scient phys Sci 2009, 21(3), 613-8.

This paper reports results of electrical conductivity (s) and Seebeck coefficient (S) measurements on the pressed pellets of V₂Z_rO₅ and Mn₂Z_rO₅ in the temperature range 500 - 1200 K. It has been found that these compounds are almost insulators. In general log σT vs T^-1 as well as S vs T^-1 plots yield two linear temperature regions. The sign of S indicates the charge carriers are electrons in the studied temperature range. The studied zirconates undergo a phase transition at 810 K and 785 K respectively. The conduction mechanism in these solids in intrinsic band type with O^2-: 2p and M³⁺ : 4s bands as valence and conduction band. Energy band gap and mobility of the charge carriers have also been evaluated.

2 tables, 11 ref

012172   Gaur K;Singh S (Physics Dep, K.N. Govt. P.G. College, Gyanpur, Bhadohi) : Electrical conduction in trivalent nickel and chromum zirconates. Ultra Scient phys Sci 2009, 21(3), 505-8.

The electrical conductivity (σ) and Seebeck coefficient (S) of trivalent Nickel and Chromium zirconates are measured in the temperature range 500-1200K. It has been concluded that chromium zirconate undergoes a phase transition at 790 and nickel zirconate at 750K. In - certain temperature ranges log σ and S depend linearly on T^-1. It is shown that conduction mechanism in these solids is essentially band type with O^2-: 2p and M³⁺: 4s (transition metal 4s) bands as valence and conduction band. Energy band gap and mobility of the charge carriers have also been evaluated.

2 tables, 9 ref

012171   Ganeswar Nath;Paikaray R (Engg. Physics Dep, Dhanewsar Rath Institute of Engg. and Management Studies (DRIEMS), Tangi, Cuttack-754 022) : Role of frequency in studying intermolecular interactions in a binary mixutre of industrial importance liquid. Ultra Scient phys Sci 2009, 21(1), 99-104.

The acoustical parameters for binary mixture of two industrial importance liquid namely di-isopropyl ether (DIPE) and xylene (mixed isomer) has been studied at three different frequencies ( 1 MHz, 3MHz and 5MHz) and at constant temperature 303K. The measured data of density (ρ) and ultrasonic velocity (C) in binary mixture of DIPE and xylene are used to compute isentropic compressibility (β), intermolecular free length (Lf) and acoustic impendence (Z) and their excess values from view point of the importance and applicability in asserting the interactions. In this binary system, the interaction parameter values have been found to be positive and their excess values are negative over entire composition range of DIPE which indicates the specific interactions between unlike molecule. With increase of frequency the extent of interaction becomes weak due to the thermal relaxation of the component molecules.

7 illus, 20 ref

012170   Enterria D;Engel R;McCauley T;Pierog T (NO, CERN, PH, CH+1211 Geneva 23, Switzerland, Email: dde@cern.ch) : Cosmic-ray Monte Carlo predictions for forward particle production in p-p, p-pb and Pb-Pb collisions at the LHC. Indian J Phys 2010, 84(12), 1837-42.

Presents and compares the predictions of various cosmic-ray Monte Carlo models for the energy (dE/dη) and particle (dN/dη) flows in p-p, p-Pb and Pb-Pb collisions at √S_NN = 14,8.8, and 5.5 TeV respectively, in the range covered by forward LHC detectors like CASTOR or TOTEM (5.2 <60> | η| <60> 6.6) and ZDC or LHCf (|η|)≥ 8.1 for neutrals).

5 illus, 27 ref

012169   Dutta Gupta N;Sahu K R;Das I;De A;De U (Variable Energy Cyclotron Cetnre, Bidhanngar, Kolkata-700 064, Email: ude@veccal.ernet.in) : Synthesis and study of electroactive nanoparticles and their polymer composites for noval applications. Indian J Phys 2010, 84(10), 1413-9.

Polymer ceramic composites using a polymer binder, nanosized BaTiO₃ and metal particles were developed for radiation shielding in the microwave region. From X-ray Diffraction (XRD) the crystallinity and nanosize of BaTiO₃ was confirmed in the composite. Interesting changes in Differential Scanning Calorimetry (DSC) were observed before and after ball milling of BaTiO₃. Shielding Efficiency (SE) of microwave radiation has been measured from transmitted fraction (TF) of electromagnetic waves (EM) at different frequencies. The changes in TF were assigned to reflection and absorption of EM waves in different composites.

5 illus, 6 ref

012168   Devlani N;Rai A K (Applied physics Dep, S.V. National Institute of Technology, Surat-395 007, Email: nayneshdev@gmail.com) : S-wave masses and decay properties of D and Ds mesons. Prajna 2010, 18(1-4), 145-7.

Mass spectra and decay properties of D and D_s mesons are investigated in the frame work of a relativistic phenomenological quark model with a confinement potential of the type v (r) = -α_c/r + Ar^v, with v varying from 0.5 to 2.5. Apart the mass spectra, the decay constants ( f_g/v) and the leptonic branching fractions are calculated in this paper with different choices of v in the range 0.5 to 2.5. The predictions are compared with other theoretical models and experimental results.

5 tables, 22 ref

012167   Deshpande M P;Chaki S;Pandya N N;Shah S C (Physics Dep, Sardar Patel Univ, Vallabh Vidyanagar, Gujarat-388 120) : Electrical transport properties of some mixed transition metal dichalcogenides Mox W1-xSe2(x=0.3, 0.4. 0.85, & 0.9. Prajna 2010, 18(1-4), 132-5.

The mixed transition metal dichalcogenide single crystals, Mo_xW_1-xSe₂ series, taking x = 0.3, 0.4, 0.85 and 0.9 were successfully grown by direct vapor transport (DVT) techniques. The variation of resistivity with temperature was studied along perpendicular and parallel to c-axis using four probes and two probe techniques respectively. The Hall measurements at ambient temperature determined the conductivity type and carrier concentration of the as-grown crystals. The Seebeck coefficient variation with temperature was carried out. The obtained results are discussed in details.

4 illus, 4 tables, 21 ref

012166   Denia C;Gerceklioglu M (Physics Dep, Ege Science Faculty Univ, Bamova - Izmir 35100, Turkey, Email: cdeniz@adu.edu.tr) : Analysis of the exactly solvable linear differential equations by the modified airy function (MAF) method. Indian J Phys 2011, 85(2), 339-57.

Appropriate second order Linear Differential Equations(LDEs) which can be solved exactly by the Modified Airy Function (MAF) method, which normally gives approximate solutions in terms of Airy functions for Schrodinger-like LDEs, have been studied in three possible cases according to the MAF theory. The results of the exactly solvable LDEs have been classified in terms of two different family of LDEs with turning point and/or singular point parameter, one of which being a new class other than the known Time Independent Schrodinger's Equation (T1SE) with a linear potential.

8 illus, 21 ref

012165   Deka M;Nath A K;Kuamr A (Physis Dep, Tezpur Univ, Napaam, Tezpur, Assam-784 028, Email: ask@tezu.ernet.in) : Ionic conduction and phase sparation studies in PEO-P(VdF-HFP)-LiCIO₄-dedoped polyaniline nanofiber composite polmer electrolytes-I. Indian J Phys 2010, 84(10), 1299-1305.

In the work, dispersion of dedoped polyaniline nanofibers into PEO-LiCIO₄ blended with P(VdF-HFP) has been discussed. Polyaniline nanofibres have been synthesized by a gentle interfacial polymerization route. The nanofibers are dedoped with base NaOH and films of PEO-P(VdF-HFP)-LiCIO₄-dedoped polyaniline nanofibres are prepared by solution casting method with varying concentration of dedoped (insulating) nanofibers (from 5 wt.% to 25 wt.%). The synthesized polymer electrolyte films have been characterized by ac impedance analysis, XRD and SEM. The ionic conductivity of PEO-P(VdF-HFP)-LiCIO₄ electrolyte system increases with increase in concentration of dedoped polyaniline nanofibers. The high aspect ratio (<62> 50) nanofibres prevent PEO-P(VdF-HFP)-LiClO₄ electrolyte matrix from reorganization resulting in increase in amorphicity that leads to enhancement in ionic conductivity. However, the XRD results show that at higher concentration (<62> 15 wt.%) the nanofibres get phase separated out from the polymer electrolyte phase and start forming insulating clusters which impedes the ion motion. SEM studies confirm the formation of domain like structure of nanofibres at higher concentration, which act as physical barrier for the conduction of Li⁺ ions.

5 illus, 26 ref

012164   De Marco N (NO, INFN-Sezione di Torino, 1, Giuria, I-10125 Torino, Italy, Email: demarco@toinfn.it) : Reaction plane determination by means of the ALICE zero degree calorimeters. Indian J Phys 2010, 84(12), 1831-5.

A possible way to estimate the reaction plane of the ion-ion collision is to measure the sideward deflection of the spectator neutrons. In the ALICE experiment this kind of measurement can be performed by means of the two neutron zero degree calorimeters (ZN), which are located at opposite sides with respect to the beam intersection point (IP). In fact the ZN calorimeters, thanks to their segmentation in four towers, are position sensitive devices. Concerning their localizing capability, a spatial resolution of ~3 mm has been measured for a 100 GeV/c hadron beam. This performance will be used to reconstruct, event by event, the centroid coordinate of the spectator neutron spot on the ZN front-face, which is sensitive to the directed flow ("bounce off") of spectator neutrons. The measurement of the centroid will therefore allow to reconstruct the 1 st-order event plane azimuth. A simulation is performed in order to estimate the dependence of the event plane resolution on the magnitude of the directed flow v₁ of the spectator neutrons and on the neutron multiplicity (event centrality). In particular, it will be shown that the event plane resolution is not dominated by the smearing on the centroid measurement, but by the smearing due to the transverse lead beam divergence at the IP. Finally a possible tool to select events with small lead beam divergence at IP is discussed, using the information coming from both the ZN calorimeters.

3 illus, 7 ref

012163   Dash P;Mallick P;Rath H;Dash B N;Tripathi A; Jai Prakash;Avashi D K;Satyam P V;Mishra N C (Physics Dep, Utkal Univ, Bhubaneswar-751 004, Email: pdash16@yahoo.com) : Surface modifications of ultra-thin gold films by swift heavy ion irradiation. Indian J Phys 2010, 84(10), 1391-7.

Gold films of thickness 10 and 20 nm grown on float glass substrate by thermal evaporation technique were irradiated with 107 MeV Ag⁺⁸ and 58 MeV Ni⁵⁺ ions at different fluences and characterized by Grazing Incidence X-ray Diffraction (GIXRD) and Atomic Force Microscopy (AFM). The pristine films were continuous and no island structures were found even at these small thicknesses. The surface roughness estimated from AFM data did not show either monotonic increase or decrease with ion fluences. Instead, it increased at low fluences and decreased at high fluences for 20 nm thick film. In the 10 nm film roughness first increased with ion fluence, then decreased and again increased at higher fluences. The pattern of variation, however, was identical for Ni and Ag beams. Both the beams led to the formation of cracks on the film surface at intermediate fluences. The observed ion-irradiation induced thickness dependent topographic modification is explained by the spatial confinement of the energy deposited by ions in the reduced dimension of the films.

5 illus, 22 ref

012162   Dash B N;Dash P;Rath H;Mallick P;Biswal R; Kulriya P K;Mishra N C (Physics Dep, Salipur College, Salipur-754 202, Email: bichidash@yahoo.co.in) : Swift heavy ion irradiation induced modification of BiFeO₃ thin films prepared by sol-gel method. Indian J Phys 2010, 84(10), 1315-20.

Reports the preparation of multiferroic BiFeO₃ thin films on ITO coated glass substrates through sol-gel spin coating method followed by thermal annealing and their modification by swift heavy ion (SHI) irradiation. X-ray diffraction and Raman spectroscopy studies revealed amorphous nature of the as deposited films. Rhombohedral crystalline phase of BiFeO₃ evolved on annealing the films at 550°C. Both XRD and Raman studies indicated that SHI irradiation by 200 MeV Au ions result in fragmentation of particles and progressive amorphization with increasing irradiation fluence. The average crystallite size estimated from the XRD line width decreased from 38 nm in pristine sample annealed at 550°C to 29 nm on irradiating these films by 200 MeVAu ions at 1 x 10¹¹ ions cm^-2. Complete amorphization of the rhombohedral BiFeO₃ phase occurs at a fluence of 1 x 10¹² ions. cm^-2. Irradiation by another ion (200 MeV Ag) had the similar effect. For both the ions, the electronic energy loss exceeds the threshold electronic energy loss for creation of amorphized latent tracks in BiFeO₃.

4 illus, 16 ref

012161   Daoyong L;Yu O;Li C;Weiran C;Shaohua S (Laboratory for Nano-Functinal Materials, Lin Yi Normal Univ, 276005, China, Email: lidaoyong@lytu.edu.cn) : SERS spectra of pyridine adsorbed on nickel film prepared by magnetron sputtering. Indian J Phys 2011, 85(2), 293-9.

As a repeating well and cheaper enhancement substrate, the nickel film was fabricated with magnetron sputtering coating instrument. Surface enhanced Raman spectra (SERS) of pyridine adsorbed on this nickel film are compared with the experimental values of gaseous pyridine, the theoretical value of pyridine solution listed in other literatures and our method is better than electro-chemical etching electrode method for large scale preparation. The enhancement factor of the nickel film is calculated and the result indicates that magnetron sputtering coating technology is feasible for obtaining good SERS active surface.

3 illus, 1 table, 22 ref

012160   Danish Azmi M (Physics Dep, Aligarh Muslim Univ, Aligarh-202 002, Email: tinku.sinha@saha.ac.in) : High voltage characteristic of large area cathode pad chambers for muon spectrometer of ALICE. Indian J Phys 2010, 84(12), 1683-7.

Large area Cathode Pad Chambers (CPC) with inner and outer radii of 23.7 cm and 117 cm respectively have been fabricated and tested for 2nd Tracking station of Muon Spectrometer of ALICE. The active area of this detector has a radiation length of less than 2% and the frames are fabricated with Peek GF-30. The anode wire plane consists of 474 anode wires of which 53% have lengths greater than 1 meter. The separation between the wire plane and the grounded cathode plane is 2.5 mm. The high voltage behaviour of the chamber have been tested under two situations. With no support below the wires to reduce sagging of long wires. With a G10 strip-support whose dimension is 950 mm x 2 mm x 2.4 mm. The High Voltage (HV) tests show that a better stability is achieved when the strip support is implemented. Therefore this solution has been adopted for operation in ALICE.

4 illus, 3 ref

012159   Dalsgaard H H (Niels Bohr Institute, Copenhangen Univ, 2100 Copenhagen, Denmark, Email: hansdalsgaard@gmail.com ) : Stopping in √S_NN = 62.4 GeV Au+Au collisions. Indian J Phys 2010, 84(12), 1825-9.

Stopping in heavy ion collisions has been measured at several energies from AGS to RHIC (spanning √S_NN = 5 GeV to √S_NN = 200 GeV). The systematics of stopping hint the onset of a collision regime that might include LHC energies. Stopping in √S_NND = 62.4 GeV Au+Au collisions contribute to the understanding of different collision systems.

4 illus, 8 ref

012158   Cunqueiro L;Dias de Deus J;Ferreiro E G; Pajares C (De Fisica de Particulas Dep, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain, Email: elena@fpaxp1.usc.es) : Fluctuations and transverse momentum distributions in the color clustering approach. Indian J Phys 2010, 84(12), 1819-23.

Presents the results on transverse momentum fluctuations, multiplicity fluctuations and transverse momentum distributions for baryons and mesons in the framework of the clustering of color sources. We determine under what conditions the initial state configurations can lead to color connection, and more specifically, if variations of the initial state can lead to a transition from disconnected to connected color clusters, modifying the number of effective sources. We find that beyond a critical point, one has a condensate, containing interacting and hence color-connected sources. This point thus specifies the onset of color deconfinement. We show that the transverse momentum and multiplicity distributions are related to each other in a defined way. We obtain a non-monotonic dependence of the p_T and multiplicity fluctuations with the number of participants. We present our results for the fluctuations and the transverse momentum distributions at RHIC energies compared to the existing experimental data and our predictions for LHC energies.

4 illus, 5 ref

012157   Cosentino M R (NO, Instituto de Fisica da Universidade de Sao Paulo, Sao Paulo, Brazil, Email: mcosent@dfn.if.usp.br ) : J/ψ production in PP collisions at √S = 200GeV in the STAR experiment. Indian J Phys 2010, 84(12), 1813-18.

Presents the J/Ψ measurement in p+p collisions within the STAR collaboration Quarkonium program. This measurements aim to be the baseline measurement of a more comprehensive systematic study of quarkonium states production in order to understand their in medium modification. Here we report the total cross section and p_T distribution, and find them to be consistent with pQCD CEM predictions as well as to previous measurements at the same center-of-mass energy.

2 illus, 9 ref

012156   Choudhury D K;Islam S (Physics Dep, Gauhati Univ, Guwahati-781 014, Email: dkc_phys@yahoo.co.in) : Analysis of non-singlet structure function in next-to-next-to-leading order at small-x. Indian J Phys 2011, 85(2), 319-28.

A more general form of non-singlet structure function in Next-to-Next-to-leading order (NNLO) by solving Dokshitzer, Gribov, Lipatoy, Altarelli, Parisi (DGLAP) equation at small-x is obtained. Results are compared with Fermi Lab Experiment E665 data.

1 illus, 36 ref

012155   Chetluru V;Barannikova O (NO, Illionis at Chicago Univ, 845 W. Taylor St. M/C 273, Chicago IL 60607-7059, Email: vchetl1@uic.edu) : Jet studies for 5.5 TeV Pb+Pb collisions Via di-hadron correlations. Indian J Phys 2010, 84(12), 1807-11.

Understanding the energy loss mechanisms in hot and dense QCD matter is an important aspect of phase diagram exploration at the Relativistic Heavy Ion Collider (RHIC). A wide variety of experimental studies are devoted to this subject. With the start of the experimental program at the Large Hadron Collider (LHC) such studies will be taken to a new energy domain lending to crucial new insights on the properties of the new state of matter. Investigates the possibility of utilizing di-hadron correlation techniques for probing the medium created in heavy ion collisions at the 5.5 TeV with a generic hadron detector. Discusses characterization of the jet yields, fragmentation functions, and energy estimates on near- and away- sides in triggered di-hadron correlations.

3 illus, 13 ref

012154   Chen J (Institution of Particle Physics, Huazhong Normal Univ, (CCNU), Wuhan 430079, People's Republic of China, Email: chenjy@iopp.ccnu.deu.cn) : Directed flow of identified particles form Au+ Au collisions at RHIC. Indian J Phys 2010, 84(12), 1801-5.

Presents the measurement of directed flow (v<1) for the identified particles, namely, Λ, Λ and K⁰_s, as a function of rapidity and centrality in Au+Au collisions at √S_NN = 200 GeV and 62.4 GeV. The measurement is based on the run IV data obtained by the STAR experiment at RHIC. In order to enhance event plane resolution, use tracks reconstructed from the Forward Time Projection Chambers (FTPCs), together with the sideward deflection of spectator neutrons measured by the STAR'S Shower Maximum Detector at Zero Degree Calorimeters (ZDC-SMDs). We find that for 200 GeV, proton and antiproton v₁ is less than 1%, the K⁰_s, Λ, Λ v₁ is less than 2% ; for 62 GeV, proton v₁ is less than 1% and antiproton is less than 2%, v₁ for K⁰_s Λ, Λ is less than 2% in Au+Au collisions at 200 GeV.

4 illus, 11 ref

012153   Chatterjee R;Srivastava D K;Heinz U;Gale C (NO, Variable Energy Cyclotron Centre, 1/AF, Bidhan Nagar, Kolkata-700 064) : Exploring evolution of anisotropy with electromagnetic radiation. Indian J Phys 2010, 84(12), 1795-9.

Authors have shown that elliptic flow (v₂) of thermal electromagnetic radiation reflects anisotropy of the partonic phase at high values of transverse momentum as well as invariant mass, which is quite different in nature compared to the ideal hydrodynamics predicted V₂ of hadrons. Spatial eccentricity scaled v₂ values remain unchanged with change in impact parameter. Different temporal contours of spectra and v₂ explain relative contributions from different phases to the overall v₂, its nature and its gradual build-up very well.

2 illus, 7 ref

012152   Chandra V;Ravindra Kumar;Ravishankar V (Physics Dep, Indian Institute of Technology Kanpur, Kanpur-208 126, Email: vinodc@iitk.ac.in) : Hot QCD equations of state and RHIC. Indian J Phys 2010, 84(12), 1789-93.

Showed how hot QCD equations of states can be adapted to make definite predictions for quark-gluon plasma at RHIC. Considers equations of state up to O(g⁵) and O[g⁶(In(1/g) + δ)]. The method involves the extraction of equilibrium distribution functions for gluons and quarks from these equations of state by capturing the interaction effects entirely in the effective chemical potentials. Further utilize these distribution functions to study the screening length in hot QCD and dissociation phenomenon of heavy quarkonia states by combining this understanding with the semi-classical transport theory.

1 illus, 1 tables, 11 ref

012151   Cerci S;Enterria D (NO, Cukurova Univ, Adana, Turkey, Email: salim.cerci@cern.ch) : Low-xQCD studies with forward jets in p-p at 14 TeV. Indian J Phys 2010, 84(12), 1783-8.

The Large Hadron Collider will provide hadronic collisions at energies in the multi-TeV range, never explored before. The parton fractional momenta probed at such energies can be as low as X ≈ 2p_T/√se^-y ≈ 10^-5 at large rapidities y, opening up attractive opportunities for low-x QCD studies. The combination of the CMS HF (3 <60> | η | <60> 5) and CASTOR (5.1 <60> |η| <60> 6.6) calorimeters allows one, in particular, to reconstruct very forward jets. We present generator-level studies of the CMS capabilities to measure the single inclusive forward jet spectrum and forward-backward (Mueller-Navelet) dijets in p-p collisions at 14 TeV. Both observables are sensitive to low-x gluon densities and non-linear QCD evolution.

4 illus, 20 ref

012150   Burau G;Bleidel J;Fuchs C (Institut of Theoretische Physik, Johann Wolfgang Goethe-Universitat, Max-von-Laue-str. 1, D-60438 Framlfirt am main, Germany, Email: burau@th.physik.uni-frankfurt.de) : Parton rearrangement and fast thermalization in heavy-ion collisions at RHIC and LHC energies. Indian J Phys 2010, 84(12), 1777-81.

The implications of parton rearrangement processes on the dynamics of ultra-relativistic heavy-ion collisions have been investigated. A microscopic transport approach, namely the quark gluon string model (QGSM) which has been extended for a locally density-dependent partonic rearrangement and fusion procedure served as the tool for this investigations. The model emulates effectively the dynamics of a strongly coupled quark plasma and final hadronic interactions. Main QGSM results on anisotropic flow components v₁ and v₂ at top RHIC energy are compiled. Predictions for the pseudorapidity dependence of directed and elliptic flow in Pb+Pb collisions under LHC conditions are presented.

3 illus, 34 ref

012149   Braidot E (Utrecht Univ, Princetonplein 5, 3584 CC, Utrecht, The Netherlands, Email: braidot@rcf.fhic.bnl.gov) : Searching for the color glass condensate with the star forward meson spectrometer. Indian J Phys 2010, 84(12), 1771-5.

Early results from the Solenoidal Tracker At RHIC (STAR) using prototype forward calorimeters (FPD/FPD++) have shown that in d+Au collisions at √S_NN = 200 GeV a stronger suppression of forward π⁰ yield is observed than would be expected from shadowing effects. Exploratory measurements and observations can be qualitatively interpreted using the Color Glass Condensate (CGC) model to describe the colliding nucleus. A new detector, the Forward Meson Spectrometer (FMS), has been built to measure forward pion and photon production to quantify gluon suppression at low x in heavy nuclei over a large range in x and p_T.

2 illus, 11 ref

012148   Bluhm M;Kampfer B (Forsechungszentrum Dresden-Rossendorf, Institut fur Strehlenphysik, PF 540119, 01314, Dresden, Germany, Email: m.bluhm@fzd.de) : Quasiparticle model for the quark-gluon plasma: equation of state near T_c. Indian J Phys 2010, 84(12), 1765-9.

Authors test the quark mass dependence implemented in the quasiparticle dispersion relations of our quasiparticle model for the QCD equation of state by comparing with recently available lattice QCD data employing almost physical quark masses. In addition, we emphasize the capability of our model to successfully describe lattice QCD results for imaginary chemical potential and to analytically continue the latter to real chemical potential.

2 illus, 22 ref

012147   Bishoyi K S;Mohapatra S P;Rout G C (PG Dep of Physics, Fakir Mohan College, Balasore-756 001, Email: bishoyi@iopb.res.in) : Interplay of superconductivity and magnetism in presence of inter sub-lattice effect in cuprates. Indian J Phys 2010, 84(10), 1327-32.

Reports a model Hamiltonian to study the interplay between the two long range orders of anti-ferromagnetism (AFM) and superconductivity (SC) in cuprate superconductors in presence of the intersite pairing effect. The BCS type but non-phonon pairing mechanism is considered among the electrons of two equivalent 'Cu' sites. The pairing among the electrons of two nearest neighbour non-equivalent 'Cu' sites is included in the Hamiltonian and its effect on the interplay of SC and AFM is investigated. The Hamiltonian is solved by the Green's function method and the corresponding gap equations are calculated and solved self-consistently. The influence of model parameters like AFM coupling (λ₀), SC couling (λ₁) and the coupling (λ₂) for intersite superconducting interactions on the gaps (SC and AFM) are studied numerically and the results are reported.

3 illus, 7 ref

012146   Bhutadia H;Korot K;Antony B;Vinodkumar M (NO, V. P. & R. P. T. P. Science College, Vallabh Vidyanagar-388 120) : Screening -corrected electron impact total and ionization cross sections for N(CH₃)_n and P (CH₃)₃. Prajna 2010, 18(1-4), 140-4.

Reports a modified calculation for total elastic, total ionization and total (complete) cross sections for Trimethylamine N(CH₃)₃ and Trirriethylphosphine, P(CH₃)₃ upon electron impact at energies from circa threshold to 2000 eV. We have proposed a model which allows screening correction resulting due to the overlapping of atoms as seen by incident electrons in a complex molecule. Author have employed well known Spherical Complex Optical Potential (SCOP) formalism to evaluate total elastic and total inelastic cross sections and hence, total (complete) cross sections. The ionization cross sections were derived using the Complex Optical Potential - ionization contribution (CSP-ic) method. Present results are compared with available experimental and other theoretical data wherever available and overall good agreement is observed. Present screening-corrected model shows improvement over the previous method especially at low energies.

4 illus, 1 table, 18 ref

012145   Bhushan S;Shrivastava A (Physics Dep, Pt. Ravishankar Shukla Univ, Raipur-492 010, Email: bhushan_312006@rediffmail.com) : Photoconductivity and photoluminescence in chemically deposited films of (Cd_0.95-Pb_0.05)S: CdCe₂, Ce. Indian J Phys 2010, 84(11), 1517-26.

The results of photoconductivity (PC), photoluminescence (PL), optical absorption spectra, XRD and SEM studies are presented for (Cd_0.95-Pb_0.05)S : CdCl₂,Ce films prepared by chemical bath deposition technique. PC gains -10⁷ are found in doped films. PL emission spectrum is found in red region which is related to 5 d to 4f transition in Ce. Films prepared at 60°C show better PC while those prepared at room temperature (RT) show better PL. Optical absorption studies show reduction in band gap due to addition of PbS. A peak due to Ce is also observed in absorption spectrum. XRD studies show the presence of both CdS and PbS. SEM studies show presence of microcrystals, cluster of grains along with some rod type structures.

6 illus, 1 tables, 22 ref

012144   Bhattacharyya A;Ghosh S K;Mallick R;Raha S (Physics Dep, Calcutta Univ, 92, A. P. C. Road, Kolkata-700 009) : Explaining GRB in the light of energy deposition rate for v+v→e<. Indian J Phys 2010, 84(12), 1759-63.

Authors have studied the v + v → e⁺ + e^- energy deposition rate near a rotating compact star which is important for the study of gamma ray bursts (GRB). The General relativistic (GR) and rotational effects increase the efficiency of the process immensely. The rotational effect also brings about an asymmetry in the deposition rate of the star.

2 illus, 11 ref

012143   Bhattacharya L;Roy P K (High Energy Physics Div, Saha Institute of Nuclear Physics, 1/AF, Bidhannagar, Kolkata-700 064, Email: iusaka.bhattacharya@saha.ac.in) : Photons from jet-plasma interaction in collisional energy loss scenario. Indian J Phys 2010, 84(12), 1751-7.

Calculates photons from jet plasma interaction in a collisional energy loss scenario. It is shown that the Phenix photon data is well reproduced when photons from initial hard collisions are taken into account.

2 illus, 16 ref

012142   Bhatt N K;Jain A R (Physics Dep, Sardar Patel Univ, Vallabh Vidyanagar-388 120) : Anharmonic properties and sp-d hybridization in barium at high temperatures. Prajna 2010, 18(1-4), 148-50.

Heavy alkaline metals are characterized by close proximity of empty d-bands to the Fermi energy E_F. Effect of closeness of E_F to d-bands on different physical properties is highest in barium with substantial sp-d hybridization, which is further influenced by the application of pressure and temperature. While the evanescent form of pseudopotential is sufficient to deduce physical properties at ambient condition, it is combined to mean-field potential (MFP) approach to estimate some anharmonic physical properties of Ba at finite temperatures. Ion-motional free energy (F_ion), temperature variations of bulk modulus and anhannonic contribution to specific heat at constant volume are obtained. Most pronounced anharmonic property, the volume-thermal expansion is also obtained, but results overestimate the experimental data. Discrepancy in thermal expansion is discussed and rectified by including sp-d hybridization into the description but without considering the d-band filling effect. Good accordance of thermal expansion with the experimental findings reveals promising applicability of the present potential to investigate several other physical properties at high-T and high-P regime.

4 illus, 14 ref

012141   Bhatt H;Chandwani K;Nandi B K;Shah N K; Schandmand S;Varma R (NO, Nuclear Physics Institute, Julich Forschungszentrum-400 076, Germany, Email: s.schadmand@fz-juelich.de) : Physics with the new WASA-at-COSY facility. Indian J Phys 2010, 84(12), 1745-50.

The Wide Angle Shower Apparatus (WASA), previously operated at Uppsala, Sweden, is now installed at the COSY accelerator at Julich Forschungszentrum, Germany. The main goal of the WASA-at-COSY collaboration is to study symmetry violations in hadronic reactions focusing on η and η' decays. The Nuclear Physics Institute at Julich Forschungszentrum and Department of Physics at 1IT Bombay are collaborating to understand QCD at intermediate distance scales using the proton beam from the COSY accelerator with proton and deuteron targets. In this paper, we present the preliminary analysis on three different channels being investigated jointly by the two groups.

2 illus, 2 tables, 10 ref

012140   Bhasin A (School of Physics and Astronomy, The Birmingham Univ, Edgbaston, Birminghum, UK) : Resonance production at ALICE: ρ and φ. Indian J Phys 2010, 84(12), 1739-43.

Resonances in heavy ion experiments provide information about the medium produced in the collisions, in particular about the later stages in the evolution of the fireball. The motivation for the study of resonances at ALICE, specifically the ρ and φ mesons, is discussed. The findings of Monte Carlo studies for ρ produced in Pb-Pb collisions are outlined, and a fit to the π*π^- spectrum, including other contributions, is presented. The ρ shape, which shows some distortion, is discussed. The φ meson has a narrow width, making it more easily visible, so its significance without Particle IDentification, or PID, has been investigated. Recent work on the φ meson in simulated pp collisions is described, including a fit to the K⁺ K^- spectrum with no PID.

3 illus, 1 table, 18 ref

012139   Bhasin A (School of Physics and Astronomy, Birmingham Univ, Birmingham, United Kingdom, Email: sparsh.navin@cern.ch) : Minimum bias trigger for pp physics with ALICE. Indian J Phys 2010, 84(12), 1733-8.

ALICE will measure the properties of strongly interacting matter created in heavy-ion collisions. In addition, taking advantage of the low p_t acceptance in the central barrel, ALICE will play an important role in understanding pp collisions with minimum bias triggers at LHC energies. The proposed minimum bias trigger is sensitive to about 90% of the total inelastic cross section and 99% of the non-diffractive cross section. A procedure to calculate the trigger efficiency and an estimate of the systematic uncertainty due to the limited acceptance of the detector are presented.

1 illus, 1 table, 10 ref

012138   Bhadra J;Sarkar D (Physics Dep, Gauthati Univ, Guwahati-781 014, Email: sarkardeepali@gmail.com) : Polypyrrole nanocomposite made by polypyrrole dispersion in poly (vinyl alcohol) matrix. Indian J Phys 2010, 84(10), 1321-5.

Polypyrrole-polyvinyl alcohol (PPy-PVA) nanocomposite is synthesized by dispersing interface polymerized polypyrrole in PVA matrix. The composite films are characterized by FTIR, XRD and SEM. FTIR spectra indicates crosslinking in the composite film. XRD pictures show more crystallinity for higher polymerization temperature, whereas SEM pictures clearly indicate PPy rod formation for the same film. The electrical conductivity of the films is in the range of 10^-1 S/cm, whereas the current-voltage (I-V) characteristics shows power law behaviour.

3 illus, 21 ref

012137   Begun V V;Gorenstein M I (NO, Bogolyubov Institute for Theoretical Physics, Kiev, Ukaine, Email: viktor.begun@gmail.com) : Fluctuational signals for pion Bose Einstein condensation. Indian J Phys 2010, 84(12), 1727-32.

Consideres the Bose Einstein condensation (BEC) in a relativistic pion gas. At high collision energy, in the samples of events with a fixed number of all pions, N, the pion system may approach the conditions of the BEC. An anomalous increase of the scaled variances of neutral and charged pion number fluctuations then appears. The size of this increase is restricted by the finite size of the pion system which should increase with the collision energy.

1 illus, 8 ref

012136   Battacharya R;Nag A;Guha R;Bhoumick A;De S; Bhattacharya A B (Environmental Science Dep, Kalyani Univ, Kalyani-741 235, Email: rinaenv@yahoo.com) : Solar eclipse effects of 22 july, 2009 on the propagation of radio signals. Indian J Phys 2010, 84(11), 1587-95.

The results of investigation of the variation of radio signal strengths during the solar eclipse on July 22, 2009 are reported in this paper. Observations of the radio signals transmitted from different radio stations at different frequencies and received at a particular observing site indicate a distinct change in signal strength around the time the eclipse umbra passes the propagation paths. The three types of variations in the eclipse day and particularly during its peak period are different from propagation under normal condition. The phenomena of signal variations, the noted "Inverted U-shape" at one of the frequencies before the occurrence of the eclipse and 13 to 15 minutes time difference between the enhancement of the signal strength and the onset of eclipse are some interesting characteristics. The results are interpreted by ionospheric D-layer behavior at such times.

7 illus, 10 ref

012135   Basegmez S;Enterria D;Gouskos L;Katkov I; Katsas p;Khein L (Physics Dep, Dukurova Univ, 01330, Adana, Turkey, Email: suzan.basegmez@cern.ch) : Performance studies for the prototype III of Castor-forward calorimeter at the CMS experiment. Indian J Phys 2010, 84(12), 1689-93.

Presents preliminary results of the performance of prototype III of the CASTOR quartz-tungsten sampling calorimeter, to be installed in the very forward region of the CMS experiment at the LHC. The energy linearity and resolution, as well as the spatial resolution of the prototype to electromagnetic and hadronic showers are studied with E= 10-200 GeV electrons, E= 20-350 GeV pions, and E= 50, 150 GeV muons in beam tests carried out at CERN/SPS in 2007.

7 illus, 4 ref

012134   Barnafoldi G G;Fai G;Levai P;Cole B A;Papp G (Center for Nuclear Research, Kent State Univ, Kent, OH 44242, USA) : Cold nuclear modifications at RHIC and LHC. Indian J Phys 2010, 84(12), 1721-5.

Authors use recent nuclear parton distributions, among them the Hirai - Kumano - Nagai (HKN) and Eskola - Paukkunen - Salgado (EPS08) parameterizations, in the pQCD-improved parton model to calculate the nuclear modification factor, R_AA, (p_T), at RHIC and at the LHC. At RHIC, the deuteron-gold nuclear modification factor for pions, measured at p_T ≥ 10 GeV/c in central collisions, appears to deviate more from unity than the model results. The slopes of the calculated R_dAu(p_T) are similar to the slopes of the PHENIX pion and photon data. At LHC, without final-state effects we see a small enhancement of R_dPb(p_T) in the transverse momentum range 10 GeV/c ≥ PT ≥ 100 GeV/c for most parameterizations. The inclusion of final-state energy loss will reduce the R_dPb(P_T) values.

2 illus, 15 ref

012133   Baria J K;Jani A R (NO, V P & R P T P Science College, Vallabh Vidyanagar-388 120, Email: jay_baria@yahoo.com) : Effect of temperature on elastic constants and bulk modulus. Indian J Phys 2010, 84(11), 1509-16.

A model pseudopotential depending on an effective core radius is proposed to study the elastic constants C₁₁, C₁₂, C₄₄ and bulk modulus B of Cu, Ag, Au, Ni, Pt and Rh at various temperatures (300-1500 K). The contribution of d-like electron is taken into account by introducing repulsive short-range Born-Mayer term. An excellent agreement between theoretical investigation and experimental findings has confirmed our formalism.

3 tables, 22 ref

012132   Bannur V M (Physics Dep, Calicut Univ, Kerala-673 635) : Self-consistent quasi-particle model. Indian J Phys 2010, 84(12), 1715-19.

Reviews the recently developed self-consistent quasi-particle model of QGP and apply it to fit the lattice QCD data on (2+1) flavor QGP.

1 illus, 12 ref

012131   Baker M D;Jia J;Steinberg P (Physics Dep, Brookhaven National Laboratory, Upton, New York 11973-5000, USA) : Direct photons in ATLAS@LHC. Indian J Phys 2010, 84(12), 1709-13.

The ATLAS detector at the LHC is capable of efficiently separating photons and neutral hadrons based on their shower shapes over a wide range in η, φ, and E_T, either in addition to or instead of isolation cuts. This provides ATLAS with a unique strength for direct photon and μ-jet physics ("tomography") as well as access to the unique capability to measure non-isolated photons from fragmentation or from the medium. We present a first look at the ATLAS direct photon measurement capabilities in p+p and Pb+Pb collisions at LHC energies over the region |η| <60> 2.4.

4 illus, 2 ref

012130   Baishya R;Sarma J K (Physics Dep, J.N. College, Boko-781 123, Email: rjitboko@yahoo.co.in) : DGLAP evolution equation in NNLO at small-x and method of characteristics: non-singlet case. Indian J Phys 2010, 84(12), 1701-7.

The non-singlet structure functions have been obtained by solving Dokshitzer-Gribov-Lipatov-Altarelli-Parisi (DGLAP) evolution equations in next-next-to-leading order (NNLO) at the small-x limit. Here a Taylor series expansion has been used and then applied the method of characteristics to solve the evolution equations. Results are compared with the Fermi Lab experiment E665 data and New Muon Collaboration (NMC) data.

2 illus, 19 ref

012129   Bailhache R;Andronic A;Braun Munzinger P (NO, Gesellschaft fuer Schwerionenforschung mbH, Darmstadt, Germany) : Z<. Indian J Phys 2010, 84(12), 1695-1700.

The possibility to detect the Z⁰ in the ALICE central barrel is studied via the electronic decay channel Z⁰ → e⁺e^-. The signal and the background are simulated with the leading order event generator PYTHIA 6. The total cross-sections are taken from NLO calculations. Based on test beam data, the electron identification performance of the Transition Radiation Detector is extrapolated to high momenta. The expected yields for minimum-bias pp collisions at 14TeV are presented. An isolation cut on the single electron, together with a minimum transverse momentum cut, allows to obtain a clear signal. The expected background is of the order of 1% with the main contribution coming from misidentified pions from jets.

3 illus, 1 table, 11 ref

012128   Ayaz Ahmad M;Ahmad S;Zafar M (Physics Dep, Aligarh Muslim Univ, Aligarh-202 002, Email: sahmad2004amu@yahoo.co.in) : Intermittent and scaling behaviour of shower particles produced in the collsions of <. Indian J Phys 2010, 84(12), 1675-81.

An attempt has been made to study the intermittent and scaling behaviour of particles produced in the interactions of ²⁸Si-Em at 14.6A GeV. For this purpose, the method of normalized scaled factorial moments, F_q, has been utilized. We have also studied some interesting features regarding the occurence of non-thermal phase transition and scaling nature of F_q-moments.

3 illus, 1 table, 14 ref

012127   Aramaki Y (NO, Tokyo Univ, Tokyo, Japan, Email: aramaki@cns.s.u-tokyo.ac.jp) : Neutral pion production with respect to reaction plane in Au+Au collisions at RHIC-PHENIX. Indian J Phys 2010, 84(12), 1669-73.

Authors have measured azimuthal anisotropy of neutral pion in √s_NN = 200 GeVAu+Au collisions at Relativistic Heavy Ion Collider (RHIC). In 2007, we have installed a new detector to measure reaction plane of collisions more precisely. This new detector is called reaction plane detector (RxNP). We report the results for azimuthal anisotropy of neutral pion for each 3 centrality steps. The determination of reaction plane achieved twice better resolution than Year-2004 run.

5 illus, 3 ref

012126   Antipin K (NO, Institut fur Kermphysik, Frankfurt Univ, Germany) : Systematic study of the optimization potential for di-electron measurements in the CBM experiment. Indian J Phys 2010, 84(12), 1663-7.

Presents a systematic investigation of an optimization of the di-electron setup of the CBM experiment for the measurement of low-mass vector mesons, and establish a limit on pion misidentifi cation.

4 illus, 2 ref