Related papers: [O II] line ratios
We present results from near-infrared spectroscopy of 26 emission-line galaxies at z ~ 2 obtained with the FIRE spectrometer on the Magellan Baade telescope. The sample was selected from the WISP survey, which uses the near-infrared grism…
Using a thermal-chemical model for the generic T-Tauri disk of D'Alessio et al. (1999), we estimate the strength of the fine-structure emission lines of NeII and NeIII at 12.81 and 15.55 microns that arise from the warm atmosphere of the…
We present spatially- and velocity-resolved echelle spectroscopy for NGC 7009 obtained with the UVES spectrograph at the European Southern Observatory's Very Large Telescope. Our objective is to analyze the kinematics of emission lines…
We study the hypothesis of high metallicity clumps being responsible for the abundance discrepancy found in planetary nebulae between the values obtained from recombination and collisionaly excited lines. We generate grids of…
We have detected the [S IV] 10.5 micron and [Ne II] 12.8 micron fine-structure lines in the halo population planetary nebula (PN) DdDm 1, and set upper limits on their intensities in the halo PN H 4-1. We also present new measurements of…
We present our parameterizations of the log([NeIII]3869/[OII]3727) (Ne3O2) and log([OIII]5007/[OII]3727) ratios as comparable and effective diagnostics of ionization parameter in star-forming galaxies. Our calibrations are based on the most…
We present results on the properties of neon emission in $z\sim2$ star-forming galaxies drawn from the MOSFIRE Deep Evolution Field (MOSDEF) survey. Doubly-ionized neon ([NeIII]3869) is detected at $\geq3\sigma$ in 61 galaxies, representing…
We present results from integral field spectroscopy with PMAS. The observed field contains: five protoplanetary discs (also known as proplyds), the high-velocity jet HH 514 and a bowshock. Spatial distribution maps are obtained for…
We present measurements of the OII(3727) emission line width for a complete sample of 24 blue field galaxies (21.25<B<22, B-R<1.2) at <z>=0.25, obtained with the AUTOFIB fibre spectrograph on the Anglo-Australian Telescope. Most emission…
We present moderate and high-dispersion 1-2.5 micron spectra of the 10 arcsec nebula around P Cygni, dominated by bright emission lines of [Fe II]. Observed [Fe II] line ratios disagree with theoretical transition rates in the literature,…
We present deep high-resolution (R~15,000) and high-quality UVES optical spectrophotometry of nine planetary nebulae with dual-dust chemistry. We compute physical conditions from several diagnostics. Ionic abundances for a large number of…
Late-time spectra of stripped-envelope CC-SNe are dominated by strong [O {\sc i}] $\lambda\lambda$6300,6363 emission, caused by thermal electron excitation of forbidden [O {\sc i}] transitions. The permitted O {\sc i} 7774 \AA\ line is also…
This work reports radiative transition rates and electron impact excitation rate coefficients for levels of the n= 3, 4, 5, 6, 7, 8 configurations of Ca II. The radiative data were computed using the Thomas-Fermi-Dirac central potential…
We study the impact of deviations from the Kennicutt-Schmidt relation (quantified by the `burstiness' parameter $\kappa_s$), gas metallicity ($Z$), and density ($n$) on the observed [OIII]88$\mu$m/[CII]158$\mu$m surface brightness ratios…
In an earlier paper we modeled the far-infrared emission from a star-forming galaxy using the photoionisation code CLOUDY and presented metallicity sensitive diagnostics based on far-infrared fine structure line ratios. Here, we focus on…
The current report presents the work to investigate the recombination lines of CII in the spectra of planetary nebulae. Two CIII targets were prepared and used to generate theoretical data required in the investigation of recombination…
We present a spectrum of the planetary nebula M 2-36 obtained using the Ultra Violet and Visual Echelle Spectrograph (UVES) at the Very Large Telescope (VLT). 446 emission lines are detected. We perform an analysis of the chemical…
We investigate the systematic variation of the [OII]3727/Halpha flux line ratio as a function of various galaxy properties, i.e., luminosity, metallicity, reddening, and excitation state, for a sample of 1124 emission-line galaxies, with a…
We have used extensive libraries of model and empirical galaxy spectra (assembled respectively from the population synthesis code of Bruzual and Charlot and the fourth data release of the Sloan Digital Sky Survey) to interpret some puzzling…
We derive new self-consistent theoretical UV, optical, and IR diagnostics for the ISM pressure and electron density in the ionized nebulae of star-forming galaxies. Our UV diagnostics utilize the inter-combination, forbidden and resonance…