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Title: Long-slit Spectroscopy of Edge-on Low Surface Brightness Galaxies

Abstract

We present long-slit optical spectra of 12 edge-on low surface brightness galaxies (LSBGs) positioned along their major axes. After performing reddening corrections for the emission-line fluxes measured from the extracted integrated spectra, we measured the gas-phase metallicities of our LSBG sample using both the [N ii]/H α and the R {sub 23} diagnostics. Both sets of oxygen abundances show good agreement with each other, giving a median value of 12 + log(O/H) = 8.26 dex. In the luminosity–metallicity plot, our LSBG sample is consistent with the behavior of normal galaxies. In the mass–metallicity diagram, our LSBG sample has lower metallicities for lower stellar mass, similar to normal galaxies. The stellar masses estimated from z -band luminosities are comparable to those of prominent spirals. In a plot of the gas mass fraction versus metallicity, our LSBG sample generally agrees with other samples in the high gas mass fraction space. Additionally, we have studied stellar populations of three LSBGs, which have relatively reliable spectral continua and high signal-to-noise ratios, and qualitatively conclude that they have a potential dearth of stars with ages <1 Gyr instead of being dominated by stellar populations with ages >1 Gyr. Regarding the chemical evolution of our sample,more » the LSBG data appear to allow for up to 30% metal loss, but we cannot completely rule out the closed-box model. Additionally, we find evidence that our galaxies retain up to about three times as much of their metals compared with dwarfs, consistent with metal retention being related to galaxy mass. In conclusion, our data support the view that LSBGs are probably just normal disk galaxies continuously extending to the low end of surface brightness.« less

Authors:
; ;  [1]; ;  [2]
  1. Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, 20A Datun Road, Chaoyang District, Beijing, 100012 (China)
  2. Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States)
Publication Date:
OSTI Identifier:
22661280
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 837; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COMPARATIVE EVALUATIONS; EMISSION; EVOLUTION; GALAXIES; LOSSES; LUMINOSITY; MASS; METALLICITY; METALS; OXYGEN; RETENTION; SIGNAL-TO-NOISE RATIO; SPACE; SPECTRA; SPECTROSCOPY; STARS; SURFACES

Citation Formats

Du, Wei, Wu, Hong, Zhu, Yinan, Zheng, WeiKang, and Filippenko, Alexei V., E-mail: wdu@nao.cas.cn. Long-slit Spectroscopy of Edge-on Low Surface Brightness Galaxies. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA6194.
Du, Wei, Wu, Hong, Zhu, Yinan, Zheng, WeiKang, & Filippenko, Alexei V., E-mail: wdu@nao.cas.cn. Long-slit Spectroscopy of Edge-on Low Surface Brightness Galaxies. United States. doi:10.3847/1538-4357/AA6194.
Du, Wei, Wu, Hong, Zhu, Yinan, Zheng, WeiKang, and Filippenko, Alexei V., E-mail: wdu@nao.cas.cn. Fri . "Long-slit Spectroscopy of Edge-on Low Surface Brightness Galaxies". United States. doi:10.3847/1538-4357/AA6194.
@article{osti_22661280,
title = {Long-slit Spectroscopy of Edge-on Low Surface Brightness Galaxies},
author = {Du, Wei and Wu, Hong and Zhu, Yinan and Zheng, WeiKang and Filippenko, Alexei V., E-mail: wdu@nao.cas.cn},
abstractNote = {We present long-slit optical spectra of 12 edge-on low surface brightness galaxies (LSBGs) positioned along their major axes. After performing reddening corrections for the emission-line fluxes measured from the extracted integrated spectra, we measured the gas-phase metallicities of our LSBG sample using both the [N ii]/H α and the R {sub 23} diagnostics. Both sets of oxygen abundances show good agreement with each other, giving a median value of 12 + log(O/H) = 8.26 dex. In the luminosity–metallicity plot, our LSBG sample is consistent with the behavior of normal galaxies. In the mass–metallicity diagram, our LSBG sample has lower metallicities for lower stellar mass, similar to normal galaxies. The stellar masses estimated from z -band luminosities are comparable to those of prominent spirals. In a plot of the gas mass fraction versus metallicity, our LSBG sample generally agrees with other samples in the high gas mass fraction space. Additionally, we have studied stellar populations of three LSBGs, which have relatively reliable spectral continua and high signal-to-noise ratios, and qualitatively conclude that they have a potential dearth of stars with ages <1 Gyr instead of being dominated by stellar populations with ages >1 Gyr. Regarding the chemical evolution of our sample, the LSBG data appear to allow for up to 30% metal loss, but we cannot completely rule out the closed-box model. Additionally, we find evidence that our galaxies retain up to about three times as much of their metals compared with dwarfs, consistent with metal retention being related to galaxy mass. In conclusion, our data support the view that LSBGs are probably just normal disk galaxies continuously extending to the low end of surface brightness.},
doi = {10.3847/1538-4357/AA6194},
journal = {Astrophysical Journal},
number = 2,
volume = 837,
place = {United States},
year = {Fri Mar 10 00:00:00 EST 2017},
month = {Fri Mar 10 00:00:00 EST 2017}
}
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