- ID:
- ivo://CDS.VizieR/J/A+A/649/A42
- Title:
- BCG up to z=1.80 physical properties
- Short Name:
- J/A+A/649/A42
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- Brightest cluster galaxies (BCGs) have grown by accreting numerous smaller galaxies and can be used as tracers of cluster formation and evolution in the cosmic web. However, there is still a controversy on the main epoch of formation of BCGs, since some authors believe they have already formed before redshift z=2, while others still find them to evolve at more recent epochs. We aim to analyse the physical properties of a large sample of BCGs covering a wide redshift range up to z=1.8 and analysed in a homogeneous way, to see if their characteristics vary with redshift. As a first step, we also present a new tool to define for each cluster which galaxy is the BCG. For a sample of 137 clusters with HST images in the optical and/or infrared, we analyse the BCG properties by applying GALFIT with one or two Sersic components. For each BCG, we compute the Sersic index, effective radius, major axis position angle, surface brightness. We then search for correlations of these quantities with redshift. We find that BCGs follow the Kormendy relation (between the effective radius and the mean surface brightness), with a slope that remains constant with redshift, but with a variation with redshift of the ordinate at the origin. Although the trends are faint, we find that both the absolute magnitudes and effective radii tend to become respectively brighter and bigger with decreasing redshift. On the other hand, we find no significant correlation of the mean surface brightnesses or Sersic indices with redshift. The major axes of the cluster elongations and of the BCGs agree within 30 degrees for 73% of our clusters at redshift z<=0.9. Our results agree with the BCGs being mainly formed before redshift z=2. The alignment of the major axes of BCGs with their clusters agree with the general idea that BCGs form at the same time as clusters by accreting matter along the filaments of the cosmic web.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/148/75
- Title:
- Bent-tailed radio galaxies Chandra Deep Field South
- Short Name:
- J/AJ/148/75
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using the 1.4GHz Australia Telescope Large Area Survey, supplemented by the 1.4GHz Very Large Array images, we undertook a search for bent-tailed (BT) radio galaxies in the Chandra Deep Field South. Here we present a catalog of 56 detections, which include 45 BT sources, 4 diffuse low-surface-brightness objects (1 relic, 2 halos, and 1 unclassified object), and a further 7 complex, multi-component sources. We report BT sources with rest-frame powers in the range 10^22^<=P_1.4 GHz_<=10^26^W/Hz, with redshifts up to 2 and linear extents from tens of kiloparsecs up to about 1Mpc. This is the first systematic study of such sources down to such low powers and high redshifts and demonstrates the complementary nature of searches in deep, limited area surveys as compared to shallower, large surveys. Of the sources presented here, one is the most distant BT source yet detected at a redshift of 2.1688. Two of the sources are found to be associated with known clusters: a wide-angle tail source in A3141 and a putative radio relic which appears at the infall region between the galaxy group MZ 00108 and the galaxy cluster AMPCC 40. Further observations are required to confirm the relic detection, which, if successful, would demonstrate this to be the least powerful relic yet seen with P_1.4GHz_=9x10^22^W/Hz. Using these data, we predict future 1.4GHz all-sky surveys with a resolution of ~10 arcsec and a sensitivity of 10{mu}Jy will detect of the order of 560,000 extended low-surface-brightness radio sources of which 440,000 will have a BT morphology.
- ID:
- ivo://archive.stsci.edu/befs
- Title:
- Berkeley Extreme and Far-UV Spectrometer
- Short Name:
- BEFS
- Date:
- 22 Jul 2020 21:27:59
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The Berkeley Extreme and Far-UV Spectrometer (BEFS), flew on the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph (ORFEUS)-SPAS I and II space shuttle missions in 1993 and 1996, returning high-resolution (/3000) FUV spectra (900-1200 Å) of 75 astrophysical objects from the first flight and more than 100 from the second. EUV spectra (400-900 Å) were obtained for a subset of these targets.
- ID:
- ivo://mast.stsci/ssap/befs
- Title:
- Berkeley Extreme and Far-UV Spectrometer
- Short Name:
- BEFS
- Date:
- 03 Feb 2021 15:45:57
- Publisher:
- Space Telescope Science Institute Archive
- Description:
- The Berkeley Extreme and Far-UV Spectrometer (BEFS), flew on the Orbiting and Retrievable Far and Extreme Ultraviolet Spectrograph (ORFEUS)-SPAS I and II space shuttle missions in 1993 and 1996, returning high-resolution (/3000) FUV spectra (900-1200 Å) of 75 astrophysical objects from the first flight and more than 100 from the second. EUV spectra (400-900 Å) were obtained for a subset of these targets.
- 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.
- 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.
307. 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.
