Anomalous Raman scattering from phonons and electrons of superconducting FeSe0.82_{0.82}

We report interesting anomalies in the temperature dependent Raman spectra of FeSe$_{0.82}$ measured from 3K to 300K in the spectral range from 60 to 1800 cm$^{-1}$ and determine their origin using complementary first-principles density functional calculations. A phonon mode near 100 cm$^{-1}$ exhibits a sharp increase by $\sim$ 5% in frequency below a temperature T$_s$ ($\sim$ 100 K) attributed to strong spin-phonon coupling and onset of short-range antiferromagnetic order. In addition, two high frequency modes are observed at 1350 cm$^{-1}$ and 1600 cm$^{-1}$, attributed to electronic Raman scattering from ($x^2-y^2$)to $xz$ / $yz$ $d$-orbitals of Fe.Comment: 19 pages, 4 figures, 1 tabl

Evidence of early multi-strange hadron freeze-out in high energy nuclear collisions

Recently reported transverse momentum distributions of strange hadrons produced in Pb(158AGeV) on Pb collisions and corresponding results from the relativistic quantum molecular dynamics (RQMD) approach are examined. We argue that the experimental observations favor a scenario in which multi-strange hadrons are formed and decouple from the system rather early at large energy densities (around 1 GeV/fm$^3$). The systematics of the strange and non-strange particle spectra indicate that the observed transverse flow develops mainly in the late hadronic stages of these reactions.Comment: 4 pages, 4 figure

Time Dependence of Chemical Freeze-out in Relativistic Heavy Ion Collisions

We investigate chemical and thermal freeze-out time dependencies for strange particle production for CERN SPS heavy ion collisions in the framework of a dynamical hadronic transport code. We show that the Lambda yield changes considerably after hadronization in the case of Pb+Pb collisions, whereas for smaller system sizes (e.g. S+S) the direct particle production dominates over production from inelastic rescattering. Chemical freeze-out times for strange baryons in Pb+Pb are smaller than for non-strange baryons, but they are still sufficiently long for hadronic rescattering to contribute significantly to the final Lambda yield. Based on inelastic and elastic cross section estimates we expect the trend of shorter freeze-out times (chemical and kinetic), and thus less particle production after hadronization, to continue for multi-strange baryons.Comment: 10 pages, 7 postscript figure

Effect of Three-body Interaction on Phase Transition of Hot Asymmetric Nuclear Matter

The properties and the isospin dependence of the liquid-gas phase transition in hot asymmetric nuclear matter have been investigated within the framework of the finite temperature Brueckner-Hartree-Fock approach extended to include the contribution of a microscopic three-body force. A typical Van der Waals structure has been observed in the calculated isotherms (of pressure) for symmetric nuclear matter implying the presence of the liquid-gas phase transition. The critical temperature of the phase transition is calculated and its dependence on the proton-to-neutron ratio is discussed. It is shown that the three-body force gives a repulsive contribution to the nuclear equation of state and reduces appreciably the critical temperature and the mechanical instable region. At fixed temperature and density the pressure of asymmetric nuclear matter increases monotonically as a function of isospin asymmetry. In addition, it turns out that the domain of mechanical instability for hot asymmetric nuclear matter gradually shrinks with increasing asymmetry and temperature. We have compared our results with the predictions of other theoretical models especially the Dirac Brueckner approach. A possible explanation for the discrepancy between the values of the critical temperature predicted by the present non-relativistic Brueckner calculations including the three-body force and the relativistic Dirac-Brueckner method is given.Comment: 16 pages, 5 figure

A COMMUNITY BASED CROSS-SECTIONAL STUDY: INCREASING PREVALENCE OF TYPE 2 DIABETES AMONG RURAL ADULT POPULATION OF KARNATAKA, INDIA

A community based cross-sectional study in the age group 25 years and above conducted at the field area of primary health centre Chakenahalli, Hassan district, Karnataka, India. The population was similar in characteristics regarding occupation, socio-economic status and food habits. Total of 626 subjects were included by multi-stage sampling. Information collected by the interviewers through face to face interview, after informed consent. The individuals were assessed on anthropometric parameters and screening was done by Random Blood Glucose (RBG) with a standardized technique; diagnosis of type 2 diabetes done by WHO criteria. Prevalence of diabetes was found in 11.3% males and 15% females, altogether the total prevalence was 13.09% with 8.79% self reported cases of diabetes . Hypertension was associated with 25.6% diabetic subjects. It was also observed that 28.1% of study population had BMI ≥ 25

A tapered multi-gap multi-aperture pseudospark-sourced electron gun based X-band slow wave oscillator

The experimental study of a tapered, multi-gap, multi-aperture pseudospark-sourced electron gun based X-band plasma assisted slow wave oscillator is presented. The designed electron gun is based on the pseudospark discharge concept and has been used to generate a high current density and high energy electron beam simultaneously. The distribution of apertures has been arranged such that the field penetration potency inside the backspace of the hollow-cathode is different while passing through the tapered gap region. This leads to non-concurrent ignition of the discharge through all the channels which is, in general, quite challenging in the case of multi-aperture plasma cathode electron gun geometries. Multiple and successive hollow cathode phases are reported from this electron gun geometry, which have been confirmed using simulations. This geometry also has led to the achievement of ∼71% fill factor inside the slow wave oscillator for an electron beam of energy of 20 keV and a beam current density in the range of 115-190 A/cm2 at a working argon gas pressure of 18 Pa. The oscillator has generated broadband microwave output in the frequency range of 10-11.7 GHz with a peak power of ∼10 kW for ∼50 ns

Cooling of Neutron Stars: Two Types of Triplet Neutron Pairing

We consider cooling of neutron stars (NSs) with superfluid cores composed of neutrons, protons, and electrons (assuming singlet-state pairing of protons, and triplet-state pairing of neutrons). We mainly focus on (nonstandard) triplet-state pairing of neutrons with the $|m_J| = 2$ projection of the total angular momentum of Cooper pairs onto quantization axis. The specific feature of this pairing is that it leads to a power-law (nonexponential) reduction of the emissivity of the main neutrino processes by neutron superfluidity. For a wide range of neutron critical temperatures $T_{cn}$, the cooling of NSs with the $|m_J| = 2$ superfluidity is either the same as the cooling with the $m_J = 0$ superfluidity, considered in the majority of papers, or much faster. The cooling of NSs with density dependent critical temperatures $T_{cn}(\rho)$ and $T_{cp}(\rho)$ can be imitated by the cooling of the NSs with some effective critical temperatures $T_{cn}$ and $T_{cp}$ constant over NS cores. The hypothesis of strong neutron superfluidity with $|m_J| = 2$ is inconsistent with current observations of thermal emission from NSs, but the hypothesis of weak neutron superfluidity of any type does not contradict to observations.Comment: 10 pages, 6 figure

Evolution of Baryon-Free Matter Produced in Relativistic Heavy-Ion Collisions

A 3-fluid hydrodynamic model is introduced for simulating heavy-ion collisions at incident energies between few and about 200 AGeV. In addition to the two baryon-rich fluids of 2-fluid models, the new model incorporates a third, baryon-free (i.e. with zero net baryonic charge) fluid which is created in the mid-rapidity region. Its evolution is delayed due to a formation time $\tau$, during which the baryon-free fluid neither thermalizes nor interacts with the baryon-rich fluids. After formation it thermalizes and starts to interact with the baryon-rich fluids. It is found that for $\tau$=0 the interaction strongly affects the baryon-free fluid. However, at reasonable finite formation time, $\tau$=1 fm/c, the effect of this interaction turns out to be substantially reduced although still noticeable. Baryonic observables are only slightly affected by the interaction with the baryon-free fluid.Comment: 17 pages, 3 figures, submitted to the issue of Phys. of Atomic Nuclei dedicated to S.T. Belyaev on the occasion of his 80th birthday, typos correcte