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Item Detailed characterisation of LINERs and retired galaxies in the local universe(Cambridge University Press, 2021) Mazengo, Daudi T.; Pović, Mirjana; Jiwaji, Noorali T.; Sunzu, Jefta M.We present a detailed characterisation of physical properties of low-ionization nuclear emission-line regions (LINERs) and retired galaxies (RGs) in the local universe for redshift range 0 < z < 0.4 and two subranges z < 0.4 and 0.1 < z < 0.4. Furthermore, we test the effectiveness of WHAN diagnostic diagram in separating the two populations. We used photometric data, public spectroscopic data and morphological classification from SDSS-DR8, MPA-JHU SDSS-DR8 catalogue and Galaxy Zoo survey, respectively. We studied the distribution of LINERs, RGs and AGN-LINERs in relation to luminosity, stellar mass, star formation rate (SFR), colour, and their location on the SFR-stellar mass and colour-stellar mass diagrams. We then studied the morphologies of both populations. Results have shown that for higher redshift range, AGN-LINERs have higher apparent g magnitude, SFRs and dominate on/above the main sequence (MS) of star formation compared to RGs. However, both populations have similar stellar mass and luminosity distributions at all redshift ranges hence suggesting a significant difference in terms of star formation of RGs and AGN-LINERs with redshift. However, larger and more complete samples of LINERs are needed from the future surveys (e.g., LSST) and missions (e.g., JWST) to study in more details the properties of RGs and AGN-LINERs and find alternative methods of separating the two populations, since using simply WHAN diagram from our study we do not find it to be effective for separating the two populations.Item Physical, optical absorption and EPR studies on fluoro-bismuthate glasses(IOP Publishing, 2015) Srinivasua, Ch.; Samee, M.A.; Edukondalu, A.; kanth, C. Laxmi; Rahman, SyedGlasses of the xLiF-(50-x)Li2O-20SrO-30Bi2O3 system, with 0 ≤ x ≤ 20 mole % were studied by EPR and Optical measurements. The changes in both density and molar volume indicate structural modifications occur due to addition of LiF. The glass transition temperatures are observed to decrease with an increase in LiF content in the compositions. The local structure around Cu2+ ions has been examined by means of electron paramagnetic resonance and optical absorption measurements. It is observed that the spin-Hamiltonian parameters calculated from the EPR spectra are influenced by the glass composition. The Cu2+ ions are in well-defined axial sites but subjected to small distortion leading to the broadening of the spectra. The spin-Hamiltonian parameter values indicate that the ground state of Cu2+ is and the site symmetry around Cu2+ ions is tetragonally distorted octahedral. The optical absorption spectra exhibited a broad band corresponding to the d-d transition bands of Cu2+ ion. By correlating EPR and optical absorption data, the bond parameters are evaluated.