Spectroscopic Study of Blue Compact Galaxies II. Spectral Analysis and Correlations

Abstract

This is the second paper in a series studying the star formation rates, stellar components, metallicities, and star formation histories and evolution of a sample of blue compact galaxies. We analyzed spectral properties of 97 blue compact galaxies, obtained with the Beijing Astronomical Observatory (China) 2.16 m telescope, with spectral range 3580Å-- 7400Å. We classify the spectra according to their emission lines: 13 of the total 97 BCGs sample are non-emission line galaxies (non-ELGs); 10 have AGN-like emission (AGNs), and 74 of them are star-forming galaxies (SFGs). Emission line fluxes and equivalent widths, continuum fluxes, the 4000 ÅBalmer break index and equivalent widths of absorption lines are measured from the spectra. We investigate the emission line trends in the integrated spectra of the star-forming galaxies in our sample, and find that: 1) The equivalent widths of emission lines are correlated with the galaxy absolute blue magnitude $M_B$; lower luminosity systems tend to have larger equivalent widths. 2) The equivalent width ratio [NII]6583/H$\alpha$ is anti-correlated with equivalent width H$\alpha$; a relationship is given that can be used to remove the [NII] contribution from blended H$\alpha$ + [NII]6548, 6583. 3) The [OII], H$\beta$, H$\gamma$ and H$\alpha$ fluxes are correlated; those can be used as star formation tracers in the blue. 4) The metallicity indices show trends with galaxy absolute magnitude and attenuation by dust; faint, low-mass BCGs have lower metallicity and color excess.

25 pages, 9 color ps-figures, accepted for publication in Astronomy and Astrophysics

References in corpus (7)

• Nebular Emission from Star-Forming Galaxies
• Dynamics of blue compact galaxies, as revealed by their H$\alpha$ velocity fields II. Mass models and the starburst triggering mechanism
• Star Formation in a Complete Spectroscopic Survey of Galaxies
• A probabilistic formulation for Empirical Population Synthesis: Sampling methods and tests
• The He abundance in the metal-deficient blue compact dwarf galaxies Tol 1214-277 and Tol 65
• Global Emission Line Trends in Spiral Galaxies: The Reddening and Metallicity Sequences
• Spectroscopic study of blue compact galaxies: I. The spectra

Cited by in corpus (38)

• A new population of ultra-long duration gamma-ray bursts
• The Abundance Properties of Nearby Late-Type Galaxies.I. The Data
• Theoretical Modeling of Star-Forming Galaxies I. Emission Line Diagnostic Grids for Local and Low-Metallicity Galaxies
• Revealing the cold dust in low-metallicity environments: I - Photometry analysis of the Dwarf Galaxy Survey with Herschel
• The Xinglong 2.16-m Telescope: Current Instruments and Scientific Projects
• The Host Galaxies of Gamma-Ray Bursts I: ISM Properties of Ten Nearby Long-Duration GRB Hosts
• Spectroscopic study of blue compact galaxies V. oxygen abundance and the metallicity-luminosity relation
• An XMM-Newton spectral survey of 12 micron selected galaxies. II. Implications for AGN selection and unification
• Massive star formation in Wolf-Rayet galaxies. III: Analysis of the O and WR populations
• Massive star formation in Wolf-Rayet galaxies: II. Optical spectroscopy results
• SDSS 0809+1729: Connections Between Extremely Metal Poor Galaxies and Gamma Ray Burst Hosts
• Kinematics and excitation of the ram pressure stripped ionized gas filaments in the Coma cluster of galaxies
• The [OII]/Halpha ratio of emission line galaxies in the 2dF redshift survey
• SN 2007uy - metamorphosis of an aspheric Type Ib explosion
• The Origin of the 4.5 micron Excess from Dwarf Galaxies
• Spectroscopic study of blue compact galaxies III. Empirical population synthesis
• Spectroscopic study of blue compact galaxies IV. Star formation rates and gas depletion timescales
• Comparison of Theoretical Starburst Photoionisation Models for Optical Diagnostics
• Elemental Abundances of Blue Compact Dwarfs from mid-IR Spectroscopy with Spitzer
• Mapping the properties of blue compact dwarf galaxies: integral field spectroscopy with PMAS
• Wolf-Rayet Galaxies in the Sloan Digital Sky Survey: the metallicity dependence of the initial mass function
• Multi-Wavelength Studies of Spectacular Ram Pressure Stripping of a Galaxy. II. Star Formation in the Tail
• The environment of AGN dwarf galaxies at z$\sim$0.7 from the VIPERS survey
• High resolution spectroscopy of the BCD galaxy Haro 15:I. Internal kinematics
• The metallicities of luminous, massive field galaxies at intermediate redshifts
• Enhanced Abundances in Spiral Galaxies of the Pegasus I Cluster
• Study of star formation in NGC 1084
• Star formation rates and chemical abundances of emission line galaxies in intermediate-redshift clusters
• The OTELO survey: Faint end of the luminosity function of [OII] emitters at <z>= 1.43
• Star formation in Blue compact dwarf galaxies: Mkn 104 & I Zw 97
• The dependence of the IR-radio correlation on the metallicity
• Ionizing Radiation Escape from Low-Redshift Galaxies and Its Connection to Cosmic Reionization
• Ultraviolet ISM Diagnostics for Star-Forming Galaxies I. Tracers of Metallicity and Extinction
• Star Formation in Satellite Galaxies
• Ionization Source of a Minor-axis Cloud in the Outer Halo of M82
• The COSMOS Wall at z$\sim$0.73: star-forming galaxies and their evolution in different environments
• Obscured and unobscured X-ray AGNs I: Host galaxy properties
• Empirical Population Synthesis for 74 Blue Compact Galaxies