LeMMINGs - IV. The X-ray properties of a statistically complete sample of the nuclei in active and inactive galaxies from the Palomar sample
Journal article, 2022
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 le gac y surv e y. Here, we present Chandr a 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 H II galaxies and absorption line galaxies (ALG). The X-ray flux limit of our surv e y is 1.65 ×10 -14 erg s -1 cm -2 (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 H II galaxies, but cannot completely rule out contamination from non-AGN processes in sources with nuclear luminosities ≲ 10 39 erg s -1 . 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 H II galaxies, which are mostly detected with Eddington ratios ≲ 10 -3 . Using [ O III ] line measurements and black hole masses from the literature, we show that LINERs, H II galaxies and ALGs follow similar correlations to low luminosities, suggesting that some 'inactive' galaxies may harbour AGN.
X-rays: Galaxies
Galaxies: Active
Author
D. R.A. Williams
University of Southampton
University of Manchester
University of Oxford
M. Pahari
University of Southampton
IIT Hyderabad
R. D. Baldi
Istituto di Radioastronomia
University of Southampton
I. M. McHardy
University of Southampton
S. Mathur
Ohio State University
Eureka Scientific
R. J. Beswick
University of Manchester
A. Beri
University of Southampton
Indian Institute of Science
P. Boorman
Czech Academy of Sciences
Susanne Aalto
Chalmers, Space, Earth and Environment, Astronomy and Plasmaphysics
Antxon Alberdi
Institute of Astrophysics of Andalusia (IAA)
M. K. Argo
University of Central Lancashire
B. T. Dullo
Complutense University
D. M. Fenech
University of Cambridge
D. A. Green
University of Cambridge
J. H. Knapen
University of La Laguna
Instituto de Astrofísica de Canarias
Ivan Marti-Vidal
Universitat de Valencia
J. Moldon
Institute of Astrophysics of Andalusia (IAA)
University of Manchester
C. G. Mundell
University of Bath
T. Muxlow
University of Manchester
F. Panessa
Istituto nazionale di astrofisica (INAF)
M.A. Pérez-Torres
Institute of Astrophysics of Andalusia (IAA)
P. Saikia
New York University Abu Dhabi
F. Shankar
University of Southampton
I. R. Stevens
University of Birmingham
P. Uttley
Anton Pannekoek Institute for Astronomy
Monthly Notices of the Royal Astronomical Society
0035-8711 (ISSN) 1365-2966 (eISSN)
Vol. 510 4 4909-4928Subject Categories
Subatomic Physics
Astronomy, Astrophysics and Cosmology
Atom and Molecular Physics and Optics
DOI
10.1093/mnras/stab3310