Journal of The Korean Astronomical Society (천문학회지)

The Korean Astronomical Society (한국천문학회)
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LOW FREQUENCY OBSERVATIONS OF A RADIO LOUD DWARF GALAXY

  • Park, Songyoun (Department of Physics and Astronomy, Seoul National University) ;
  • Sengupta, Chandreyee (Yonsei University Observatory, Yonsei University) ;
  • Sohn, Bong Won (Korea Astronomy and Space Science Institute) ;
  • Paudel, Sanjaya (Department of Astronomy & Center for Galaxy Evolution Research, Yonsei University)
  • Received : 2017.05.10
  • Accepted : 2014.09.22
  • Published : 2017.10.31
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Abstract

We investigate the radio properties of the dwarf galaxy SDSS J133245.62+263449.3 which shows optical signatures of black hole activity. Dwarf galaxies are known to host intermediate mass black holes (IMBHs) with masses $M_{BH}{\sim}10^{4-6}M_{\odot}$, some of them being radio loud. Recently, Reines et al. (2013) found dwarf galaxy candidates which show signatures of being black hole hosts based on optical spectral lines. SDSS J133245.62+263449.3 is one of them; it shows a flux density of ~ 20 mJy at 1.4 GHz, which corresponds to $L_{1.4GHz}{\sim}10^{23}W\;Hz^{-1}$. This is much brighter than other black hole host dwarf galaxies. However, star formation activity can contribute to radio continuum emission as well. To understand the nature of the radio emission from SDSS J133245.62+263449.3, we imaged this radio loud dwarf galaxy at low frequencies (325 MHz and 610 MHz) using the Giant Metrewave Radio Telescope (GMRT). We present here the high resolution images from our GMRT observations. While we detect no obvious extended emission from radio jets from the central AGN, we do find the emission to be moderately extended and unlikely to be dominated by disk star formation. VLBI observations using the Korean VLBI Network (KVN) are now being planned to understand the emission morphology and radiation mechanism.

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References

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