31 research outputs found
LeMMINGs - IV. The X-ray properties of a statistically complete sample of the nuclei in active and inactive galaxies from the Palomar sample
All 280 of the statistically complete Palomar sample of nearby ( 20 degrees have been observed at 1.5 GHz as part of the LeMMINGs e-MERLIN legacy survey. IIere, 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 degrees <delta < 65 degrees. 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 survey is 1.65 x 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 less than or similar to 10(39) erg s(-1). We construct an X-ray Luminosity function (XI,F) 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 less than or similar to 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
Ultramassive black holes in the most massive galaxies: versus
[Abridged] We investigate the nature of the relations between black hole (BH)
mass () and the central velocity dispersion () and, for
core-S\'ersic galaxies, the size of the depleted core (). Our sample
of 144 galaxies with dynamically determined encompasses 24
core-S\'ersic galaxies, thought to be products of gas-poor mergers, and
reliably identified based on high-resolution HST imaging. For core-S\'ersic
galaxies -- i.e., combining normal-core ( kpc) and large-core
galaxies ( kpc), we find that correlates
remarkably well with such that (rms scatter in log of
dex), confirming previous works on the same galaxies except three new ones.
Separating the sample into S\'ersic, normal-core and large-core galaxies, we
find that S\'ersic and normal-core galaxies jointly define a single log-linear
relation with
dex, however, at the high-mass end large-core
galaxies (four with measured ) are offset upward from this relation
by (, explaining the previously reported
steepening of the relation for massive galaxies. Large-core
spheroids have magnitudes mag, half-light radii Re 10
kpc and are extremely massive . Furthermore, these
spheroids tend to host ultramassive BHs ()
tightly connected with their rather than . The less popular
relation exhibits 62% less scatter in log than the relations.Comment: 11 pages, 4 figures, accepted (2020, November 27) for publication in
Ap
The (black hole mass)-(color) relations for early- and late-type galaxies: red and blue sequences
[Abridged] Tight correlations between supermassive black hole (SMBH) mass
() and the properties of the host galaxy have useful implications
for our understanding of the growth of SMBHs and evolution of galaxies. Here,
we present newly observed correlations between and the host galaxy
total UV [3.6] color (, Pearson's r = )
for a sample of 67 galaxies (20 early-type galaxies and 47 late-type galaxies)
with directly measured in the GALEX/SG survey. The colors
are carefully measured in a homogeneous manner using the galaxies' FUV, NUV and
3.6 \micron magnitudes and their multi-component structural decompositions in
the literature. We find that more massive SMBHs are hosted by (early- and
late-type) galaxies with redder colors, but the relations for the two morphological types have slopes that differ at
level. Early-type galaxies define a red sequence in the diagrams, while late-type galaxies trace a blue
sequence. Within the assumption that the specific star formation rate of a
galaxy (sSFR) is well traced by , it follows that the
SMBH masses for late-type galaxies exhibit a steeper dependence on sSFR than
those for early-type galaxies. The and
relations for the sample galaxies reveal a
comparable level of vertical scatter in the log direction, roughly
more than the vertical scatter of the relation.
Our relations suggest different channels
of SMBH growth for early- and late-type galaxies, consistent with their
distinct formation and evolution scenarios.Comment: 27 pages, 8 figures, 6 tables, accepted for publication in Ap
Spatially resolved analysis of neutralwWinds, stars, and ionized gas kinematics with MEGARA/GTC: new insights on the nearby galaxy UGC 10205
We present a comprehensive analysis of the multiphase structure of the interstellar medium (ISM) and the stellar kinematics in the edge-on nearby galaxy UGC 10205 using integral field spectroscopy (IFS) data taken with MultiEspectrógrafo en GTC de Alta Resolución para Astronomía (MEGARA) at the GTC. We explore both the neutral and the ionized gas phases using the interstellar Na I D doublet absorption (LR−V setup, R ∼ 6000) and the Hα emission line (HR−R setup, R ∼ 18000), respectively. The high-resolution data show the complexity of the Hα emission-line profile revealing the detection of up to three kinematically distinct gaseous components. Despite of this fact, a thin-disk model is able to reproduce the bulk of the ionized gas motions in the central regions of UGC 10205. The use of asymmetric drift corrections is needed to reconciliate the ionized and the stellar velocity rotation curves. We also report the detection of outflowing neutral gas material blueshifted by ∼ 87 km s^(−1) . The main physical properties that describe the observed outflow are a total mass M_(out) = (4.55 ± 0.06) × 10^(7) Mʘ and a coldgas mass outflow rate M_(out) = 0.78 0.03 Mʘ yr^(−1) . This work points out the necessity of exploiting highresolution IFS data to understand the multiphase components of the ISM and the multiple kinematical components in the central regions of nearby galaxies
MEGARA, the R=6000-20000 IFU and MOS of GTC
MEGARA is the new generation IFU and MOS optical spectrograph built for the 10.4m Gran Telescopio CANARIAS (GTC). The project was developed by a consortium led by UCM (Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain) and UPM (Spain). The instrument arrived to GTC on March 28th 2017 and was successfully integrated and commissioned at the telescope from May to August 2017. During the on-sky commissioning we demonstrated that MEGARA is a powerful and robust instrument that provides on-sky intermediate-to-high spectral resolutions R_(FWHM) ~ 6,000, 12,000 and 20,000 at an unprecedented efficiency for these resolving powers in both its IFU and MOS modes. The IFU covers 12.5 x 11.3 arcsec2 while the MOS mode allows observing up to 92 objects in a region of 3.5 x 3.5 arcmin^(2) . In this paper we describe the instrument main subsystems, including the Folded-Cassegrain unit, the fiber link, the spectrograph, the cryostat, the detector and the control subsystems, and its performance numbers obtained during commissioning where the fulfillment of the instrument requirements is demonstrated