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LeMMINGs – IV. The X-ray properties of a statistically complete sample of the nuclei in active and inactive galaxies from the Palomar sample.
- Source :
- Monthly Notices of the Royal Astronomical Society; 3/15/2022, Vol. 510 Issue 4, p4909-4928, 20p
- Publication Year :
- 2022
-
Abstract
- All 280 of the statistically complete Palomar sample of nearby (<120 Mpc) galaxies δ > 20° have been observed at 1.5 GHz as part of the LeMMINGs e -MERLIN legacy survey. Here, we present Chandra X-ray observations of the nuclei of 213 of these galaxies, including a statistically complete sub-set of 113 galaxies in the declination range 40° <δ < 65°. We observed galaxies of all optical spectral types, including 'active' galaxies [e.g. low-ionization nuclear emission line regions (LINERs) and Seyferts] and 'inactive' galaxies like |${\rm H\, \small {II}}$| galaxies and absorption line galaxies (ALG). The X-ray flux limit of our survey is 1.65 × 10<superscript>−14</superscript> erg s<superscript>−1</superscript> cm<superscript>−2</superscript> (0.3−10 keV). We detect X-ray emission coincident within 2 arcsec of the nucleus in 150/213 galaxies, including 13/14 Seyferts, 68/77 LINERs, 13/22 ALGs and 56/100 |${\rm H\, \small {II}}$| galaxies, but cannot completely rule out contamination from non-AGN processes in sources with nuclear luminosities |$\lesssim 10^{39}$|  erg s<superscript>−1</superscript>. We construct an X-ray Luminosity function (XLF) and find that the local galaxy XLF, when including all active galactic nucleus (AGN) types, can be represented as a single power law of slope −0.54 ± 0.06. The Eddington ratio of the Seyferts is usually 2−4 decades higher than that of the LINERs, ALGs, and |${\rm H\, \small {II}}$| galaxies, which are mostly detected with Eddington ratios |$\lesssim 10^{-3}$|. Using [ |${\rm O\, \small {III}}$| ] line measurements and black hole masses from the literature, we show that LINERs, |${\rm H\, \small {II}}$| galaxies and ALGs follow similar correlations to low luminosities, suggesting that some 'inactive' galaxies may harbour AGN. [ABSTRACT FROM AUTHOR]
- Subjects :
- ACTIVE galaxies
ACTIVE galactic nuclei
X-rays
Subjects
Details
- Language :
- English
- ISSN :
- 00358711
- Volume :
- 510
- Issue :
- 4
- Database :
- Complementary Index
- Journal :
- Monthly Notices of the Royal Astronomical Society
- Publication Type :
- Academic Journal
- Accession number :
- 155145668
- Full Text :
- https://doi.org/10.1093/mnras/stab3310