Spectroscopy of Low Surface Brightness Galaxies with the Hobby-Eberly Telescope

Abstract

We have obtained low resolution spectra of nineteen red and blue low surface brightness galaxies, using the Marcario Low Resolution Spectrograph on the 9.2m Hobby-Eberly Telescope. These galaxies form a very heterogeneous class, whose spectra qualitatively resemble those of high surface brightness galaxies covering the full range of spectra seen in galaxies of Hubble types from E to Irr. We use a combination of emission line (EW(Halpha), NII/Halpha) and absorption line (Mgb, Hbeta, <Fe>) based diagnostics to investigate the star-formation and chemical enrichment histories of these galaxies. These are diverse, with some galaxies having low metallicity and very young mean stellar ages, and other galaxies showing old, super-solar metallicity stellar populations. In contrast with some previous studies which found a strong trend of decreasing metallicity with decreasing central surface brightness, we find a population of galaxies with low surface brightness and near-solar metallicity. Correlations between several of the gas phase and stellar population age and metallicity indicators are used to place contraints on plausible evolutionary scenarios for LSB galaxies. The redshift range spanned by these galaxies is broad, with radial velocities from 3400 km/s to more than 65000 km/s. A subset of the sample galaxies have published HI redshifts and gas masses based on observations with the Arecibo 305m single-dish radio telescope, which place these galaxies far off of the mean Tully-Fisher relation. Our new optical redshifts do not agree with the published HI redshifts for these galaxies. Most of the discrepancies can be explained by beam confusion in the Arecibo observations, causing erroneous HI detections for some of the galaxies.

arXiv comment31 pages, 12 figures, 7 tables. Uses emulateapj5.sty and onecolfloat5.sty, which are included. Accepted for publication in the Astronomical Journal

References in corpus (32)

• Maps of Dust IR Emission for Use in Estimation of Reddening and CMBR Foregrounds
• Starburst99: Synthesis Models for Galaxies with Active Star Formation
• Theoretical Modeling of Starburst Galaxies
• Using Strong Lines to Estimate Abundances in Extragalactic HII Regions and Starburst Galaxies
• Old Stellar Populations. VI. Absorption-Line Spectra of Galaxy Nuclei and Globular Clusters
• The Stellar Population Histories of Local Early-Type Galaxies. I. Population Parameters
• Spectroscopy of Outlying H II Regions in Spiral Galaxies: Abundances and Radial Gradients
• The Updated Zwicky Catalog (UZC)
• New light on the search for low metallicity galaxies I. The N2 method
• The dark and baryonic matter content of low surface brightness disk galaxies
• On Measuring Chemical Abundances in Distant Galaxies Using Global Emission Line Spectra
• The stellar populations of spiral galaxies
• HI observations of low surface brightness galaxies: Probing low-density galaxies
• High-resolution rotation curves of low surface brightness galaxies: Data
• E and S0 galaxies in the central part of the Coma cluster: Ages, metal abundances and dark matter
• Spectrophotometry of nearby field galaxies: the data
• The Properties of Poor Groups of Galaxies: III. The Galaxy Luminosity Function
• Oxygen Abundances in Low Surface Brightness Disk Galaxies
• On the dependence of spectroscopic indices of early-type galaxies on age, metallicity and velocity dispersion
• The Number Density of Low Surface Brightness Galaxies with 23<mu_0<25 V-mag/sqr-arcsecond
• Strong Balmer lines in old stellar populations: No need for young ages in ellipticals?
• The local space density of Sb-Sdm galaxies as function of their scalesize, surface brightness and luminosity
• Galaxy Selection and the Surface Brightness Distribution
• Stellar populations of cluster E and S0 galaxies
• The star formation histories of low surface brightness galaxies
• Red, Gas Rich Low Surface Brightness Galaxies And Enigmatic Deviations from the Tully-Fisher Relation
• The Bivariate Brightness Function of Galaxies and a Demonstration of the Impact of Surface Brightness Selection Effects on Luminosity Function Estimations
• HIPASS Detection of an Intergalactic Gas Cloud in the NGC 2442 Group
• An Extragalactic HI Cloud with No Optical Counterpart?
• CO Detections of Edge-On Low Surface Brightness Galaxies
• First Detection of CO in a Low Surface Brightness Galaxy
• LSB Galaxies and the Tully-Fisher Relation

Cited by in corpus (11)

• The flat oxygen abundance gradient in the extended disk of M83
• The Star Formation Law at Low Surface Density
• The formation and evolution of bars in low surface brightness galaxies with cold dark matter halos
• Dust Sensitivity of Absorption-Line Indices
• How Does the Surface Density and Size of Disk Galaxies Measured in Hydrodynamic Simulations Correlate with the Halo Spin Parameter?
• A new HI catalog of Low Surface Brightness galaxies out to z=0.1 - Tripling the number of massive LSB galaxies Known
• Abundance gradients in low surface brightness spirals: clues on the origin of common gradients in galactic discs
• Structure and dynamics of galaxies with a low surface-brightness disc - II. Stellar populations of bulges
• Bulge evolution in face-on spirals and low surface brightness galaxies
• The star formation history of the LSB Galaxy UGC 5889
• The HI dominated Low Surface Brightness Galaxy KKR17