- ID:
- ivo://CDS.VizieR/J/ApJ/885/160
- Title:
- Best-fit emission-line properties in NGC 5775
- Short Name:
- J/ApJ/885/160
- Date:
- 08 Mar 2022
- Publisher:
- CDS
- Description:
- The structure and kinematics of gaseous, disk-halo interfaces are imprinted with the processes that transfer mass, metals, and energy between galactic disks and their environments. We study the extraplanar diffuse ionized gas (eDIG) layer in the interacting, star-forming galaxy NGC5775 to better understand the consequences of star formation feedback on the dynamical state of the thick-disk interstellar medium. Combining emission-line spectroscopy from the Robert Stobie Spectrograph on the Southern African Large Telescope with radio continuum observations from Continuum Halos in Nearby Galaxies-an EVLA Survey, we ask whether thermal, turbulent, magnetic field, and cosmic-ray pressure gradients can stably support the eDIG layer in dynamical equilibrium. This model fails to reproduce the observed exponential electron scale heights of the eDIG thick disk and halo on the northeast (h_z,e_=0.6,7.5kpc) and southwest (h_z,e_=0.8,3.6kpc) sides of the galaxy at R<11kpc. We report the first definitive detection of an increasing eDIG velocity dispersion as a function of height above the disk. Blueshifted gas along the minor axis at large distances from the midplane hints at a disk-halo circulation and/or ram pressure effects caused by the ongoing interaction with NGC5774. This work motivates further integral field unit and/or Fabry-Perot spectroscopy of galaxies with a range of star formation rates to develop a spatially resolved understanding of the role of star formation feedback in shaping the kinematics of the disk-halo interface.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/457/4160
- Title:
- BETA pilot multi-epoch continuum survey
- Short Name:
- J/MNRAS/457/4160
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Boolardy Engineering Test Array is a 6x12m dish interferometer and the prototype of the Australian Square Kilometre Array Pathfinder (ASKAP), equipped with the first generation of ASKAP's phased array feed (PAF) receivers. These facilitate rapid wide-area imaging via the deployment of simultaneous multiple beams within an ~30deg^2^ field of view. By cycling the array through 12 interleaved pointing positions and using nine digitally formed beams, we effectively mimic a traditional 1hx108 pointing survey, covering ~150deg^2^ over 711-1015MHz in 12h of observing time. Three such observations were executed over the course of a week. We verify the full bandwidth continuum imaging performance and stability of the system via self-consistency checks and comparisons to existing radio data. The combined three epoch image has arcminute resolution and a 1{sigma} thermal noise level of 375{mu}Jy/beam, although the effective noise is a factor of ~3 higher due to residual sidelobe confusion. From this we derive a catalogue of 3722 discrete radio components, using the 35 per cent fractional bandwidth to measure in-band spectral indices for 1037 of them. A search for transient events reveals one significantly variable source within the survey area. The survey covers approximately two-thirds of the Spitzer South Pole Telescope Deep Field. This pilot project demonstrates the viability and potential of using PAFs to rapidly and accurately survey the sky at radio wavelengths.
303. B3 0003+387 field
- ID:
- ivo://CDS.VizieR/J/AJ/120/2331
- Title:
- B3 0003+387 field
- Short Name:
- J/AJ/120/2331
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present evidence for a significant overdensity of red galaxies, as much as a factor of 14 over comparable field samples, in the field of the z=1.47 radio galaxy B3 0003+387. The colors and luminosities of the brightest red galaxies are consistent with their being at z>0.8. The radio galaxy and one of the red galaxies are separated by 5" and show some evidence of a possible interaction. However, the red galaxies do not show any strong clustering around the radio galaxy or around any of the brighter red galaxies. The data suggest that we are looking at a wall or sheet of galaxies, possibly associated with the radio galaxy at z=1.47. Spectroscopic redshifts of these red galaxies will be necessary to confirm this large-scale structure.
- ID:
- ivo://CDS.VizieR/J/ApJ/898/83
- Title:
- BH masses and bulge+disk UV-3.6um color relations
- Short Name:
- J/ApJ/898/83
- Date:
- 21 Mar 2022 08:47:28
- Publisher:
- CDS
- Description:
- The tight correlations between supermassive black hole (SMBH) mass (MBH) and the properties of the host galaxy have useful implications for our understanding of the growth of SMBHs and of the evolution of galaxies. Here, we present newly observed correlations between MBH and the host galaxy total UV-[3.6] color (C_UV,tot_, Pearson's r=0.6-0.7) for a sample of 67 galaxies (20 early-type galaxies and 47 late-type galaxies) with directly measured MBH in the Galaxy Evolution Explorer/S4G survey. The colors are carefully measured in a homogeneous manner using the far-UV, near-UV, and 3.6{mu}m magnitudes of the galaxies and their multicomponent structural decompositions in the literature. We find that more massive SMBHs are hosted by (early- and late-type) galaxies with redder colors, but the M_BH_-C_UV,tot_ relations for the two morphological types have slopes that differ at ~2{sigma} level. Early-type galaxies define a red sequence in the M_BH_-C_UV,tot_ 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 L_UV_/L_3.6_, it follows that the SMBH masses for late-type galaxies exhibit a steeper dependence on sSFR than those for early-type galaxies. The M_BH_-C_UV,tot_ and M_BH_-L_3.6,tot_ relations for the sample galaxies reveal a comparable level of vertical scatter in the log MBH direction, approximately 5%-27% more than the vertical scatter of the M_BH_-{sigma} relation. Our M_BH_-C_UV,tot_ relations suggest different channels of SMBH growth for early- and late-type galaxies, consistent with their distinct formation and evolution scenarios. These new relations offer the prospect of estimating SMBH masses reliably using the galaxy color alone. Furthermore, we show that they are capable of estimating intermediate black hole masses in low-mass early- and late-type galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/831/134
- Title:
- BH masses & host galaxy dispersion vel.
- Short Name:
- J/ApJ/831/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- According to the virial theorem, all gravitational systems in equilibrium sit on a plane in the three-dimensional parameter space defined by their mass, size, and second moment of the velocity tensor. While these quantities cannot be directly observed, there are suitable proxies: the luminosity L_k_, half-light radius R_e_, and dispersion {sigma}_e_. These proxies indeed lie on a very tight fundamental plane (FP). How do the black holes (BHs) in the centers of galaxies relate to the FP? Their masses are known to exhibit no strong correlation with total galaxy mass, but they do correlate weakly with bulge mass (when present), and extremely well with the velocity dispersion through the M_{bullet}_{propto}{sigma}_e_^5.4^ relation. These facts together imply that a tight plane must also exist defined by BH mass, total galaxy mass, and size. Here, I show that this is indeed the case using a heterogeneous set of 230 BHs. The sample includes BHs from zero to 10 billion solar masses and host galaxies ranging from low surface brightness dwarfs, through bulgeless disks, to brightest cluster galaxies. The resulting BH-size-luminosity relation M_{bullet}_{propto}(L_k_/R_e_)^3.8^ has the same amount of scatter as the M_*_-{sigma} relation and is aligned with the galaxy FP, such that it is just a reprojection of {sigma}_e_. The inferred BH-size-mass relation is M_{bullet}_{propto}(M_*_/R_e_)^2.9^. These relationships are universal and extend to galaxies without bulges. This implies that the BH is primarily correlated with its global velocity dispersion and not with the properties of the bulge. I show that the classical bulge-mass relation is a projection of the M_*_-{sigma} relation. When the velocity dispersion cannot be measured (at high z or low dispersions), the BH-size-mass relation should be used as a proxy for BH mass in favor of just galaxy or bulge mass.
- ID:
- ivo://CDS.VizieR/VII/39A
- Title:
- Bibliography of Surface Photometry of galaxies
- Short Name:
- VII/39A
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (adapted from the "Documentation for the Machine-Readable Version of the Detailed bibliography of the surface photometry of galaxies by Lee E. Brotzman and Robert S. Hill (ADC), SASC-T-1-5810-5006-84, July 1984) The bibliography supplies coded information about the methods of observation and reduction, types of photometric data, limiting surface brightness, and the general purpose of each paper for about 650 galaxies and 300 references.
- ID:
- ivo://CDS.VizieR/J/MNRAS/455/2163
- Title:
- BI light curves of DDO210 pulsating variables
- Short Name:
- J/MNRAS/455/2163
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have probed the pulsating variable star content of the isolated Local Group dwarf galaxy, DDO210 (Aquarius), using archival Advanced Camera for Surveys/Hubble Space Telescope imaging in the F475W and F814W passbands. We find a total of 32 RR Lyrae stars (24 ab-type; 8 c-type) and 75 Cepheid variables. The mean periods of the ab-type and c-type RR Lyrae stars are calculated to be <Pab>=0.609+/-0.011 and <Pc>=0.359+/-0.025d, respectively. The light-curve properties of the fundamental mode RR Lyrae stars yield a mean metallicity of <[Fe/H]>=-1.63+/-0.11dex for this ancient population, consistent with a recent synthetic colour-magnitude diagram analysis. We find this galaxy to be Oosterhoff-intermediate and lacking in high-amplitude, short-period ab-type RR Lyrae, consistent with behaviour recently observed for many dwarf spheroidals and ultrafaint dwarfs in the Local Group. We find a distance modulus of {mu}=25.07+/-0.12 as determined by the RR Lyrae stars, slightly larger but agreeing with recent distance estimates from the red giant branch tip. We also find a sizable population of Cepheid variables in this galaxy. We provide evidence in favour of most if not all of these stars being short-period classical Cepheids. Assuming all of these stars to be classical Cepheids, we find that most of these Cepheids are ~ 300 Myr old, with the youngest Cepheids being offset from the older Cepheids and the centre of the galaxy. We conclude that this may have resulted from a migration of star formation in DDO210.
- ID:
- ivo://CDS.VizieR/J/ApJ/716/615
- Title:
- Binary compact object coalescence rates
- Short Name:
- J/ApJ/716/615
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we estimate binary compact object merger detection rates for LIGO, including the potentially significant contribution from binaries that are produced in elliptical galaxies near the epoch of peak star formation. Specifically, we convolve hundreds of model realizations of elliptical- and spiral-galaxy population syntheses with a model for elliptical- and spiral-galaxy star formation history as a function of redshift. Our results favor local merger rate densities of 4x10^-3^Mpc^-3^/Myr for binary black holes (BHs), 3x10^-2^Mpc^-3^/Myr for binary neutron stars (NSs), and 10^-2^Mpc^-3^/Myr for BH-NS binaries. Assuming a detection signal-to-noise ratio threshold of 8 for a single detector (in practice as part of a network, to reduce its noise), corresponding to radii Dbns of the effective volume inside of which a single LIGO detector could observe the inspiral of two 1.4M_{sun}_ NSs of 14Mpc and 197Mpc, for initial and advanced LIGO, we find event rates of any merger type of 2.9x10^-2^-0.46 and 25-400yr^-1^ (at 90% confidence level), respectively.
- ID:
- ivo://CDS.VizieR/J/MNRAS/435/1186
- Title:
- BI photometry of bulgeless galaxies
- Short Name:
- J/MNRAS/435/1186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We examine the magnitude and size evolution of bulgeless (discs with no-bulge or pseudo-bulge) galaxies up to z~0.9 in rest-frame B band. Their evolution is compared to that of normal-discs (or discs with classical bulge). The study is done for luminous sources (M_B_<=-20) in two equal-volume redshift bins (0.4<=z<0.77 and 0.77<=z<1.0) and a local range (0.02<=z<0.05). The mean surface-brightness, mu_B_, from z_mean_=0.89 to z_mean_=0.04, shows a dimming of 0.79mag/arcsec2 for bulgeless galaxies and 1.16mag/arcsec2 for normal-discs. The characteristic magnitude, M_B_, shows an increase of 0.55mag for bulgeless galaxies and 0.95mag for normal-discs. Both dimming and faintness observed since z~0.9 is more pronounced for the normal-discs by ~0.4mag. The size distribution is log-normal and both bulgeless and normal-discs show a slight increase in the mean value, <{Delta}log(R_e_)>~0.11, from z_mean_=0.89 to z_mean_=0.04. The proportion of bulgeless galaxies in the full disc sample undergoes a considerable decline with decrease in redshift. This along with the larger dimming and faintness seen for normal-discs suggests that some fraction of the bulgeless sources switch to the normal-disc morphology with time. To ascertain the validity of studying morphology in the optical, the properties of the galaxies observed in both rest-frame B and I band are compared. The common sample is more luminous in the I band but the sizes are larger in the B band for more than 74 percent of the sources. The variation in the Sersic-index values of the galaxies in the two rest-bands is minor enough to have any effect on the morphological classification.
- ID:
- ivo://CDS.VizieR/J/ApJ/826/L32
- Title:
- Black hole masses in megamaser disk galaxies
- Short Name:
- J/ApJ/826/L32
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use new precision measurements of black hole (BH) masses from water megamaser disks to investigate scaling relations between macroscopic galaxy properties and supermassive BH mass. The megamaser-derived BH masses span 10^6^-10^8^M_{sun}_, while all the galaxy properties that we examine (including total stellar mass, central mass density, and central velocity dispersion) lie within a narrower range. Thus, no galaxy property correlates tightly with M_BH_ in ~L* spiral galaxies as traced by megamaser disks. Of them all, stellar velocity dispersion provides the tightest relation, but at fixed {sigma}_*_ the mean megamaser M_BH_ are offset by -0.6+/-0.1dex relative to early-type galaxies. Spiral galaxies with non-maser dynamical BH masses do not appear to show this offset. At low mass, we do not yet know the full distribution of BH mass at fixed galaxy property; the non-maser dynamical measurements may miss the low-mass end of the BH distribution due to an inability to resolve their spheres of influence and/or megamasers may preferentially occur in lower-mass BHs.
