- ID:
- ivo://CDS.VizieR/J/MNRAS/398/1165
- Title:
- AGN in nearby galaxies
- Short Name:
- J/MNRAS/398/1165
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using Spitzer-infrared spectrograph (IRS) spectroscopy, we investigate the ubiquity of active galactic nuclei (AGN) in a complete (~94%), volume-limited sample of the most bolometrically luminous galaxies [L_IR,8-1000um_>=(0.3-20)x10^10^L_{sun}_] to D<15Mpc. Our analyses are based on the detection of the high-excitation emission line [NeV]({lambda}14.32{mu}m) (97.1eV) to unambiguously identify AGN activity. We find that 17 of the 64 infrared (IR) bright galaxies in our sample host AGN activity (~27^+8^_6_%), >=50t of which are not identified as AGN using optical spectroscopy.
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- ID:
- ivo://CDS.VizieR/J/MNRAS/444/846
- Title:
- AKARI NEP Survey sources at 18um
- Short Name:
- J/MNRAS/444/846
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first galaxy counts at 18{mu}m using the Japanese AKARI satellite's survey at the North Ecliptic Pole (NEP), produced from the images from the NEP-Deep and NEP-Wide surveys covering 0.6 and 5.8deg^2^, respectively. We describe a procedure using a point source filtering algorithm to remove background structure and a minimum variance method for our source extraction and photometry that delivers the optimum signal to noise for our extracted sources, confirming this by comparison with standard photometry methods. The final source counts are complete and reliable over three orders of magnitude in flux density, resulting in sensitivities (80 per cent completeness) of 0.15 and 0.3mJy for the NEP-Deep and NEP-Wide surveys, respectively, a factor of 1.3 deeper than previous catalogues constructed from this field. The differential source counts exhibit a characteristic upturn from Euclidean expectations at around a milliJansky and a corresponding evolutionary bump between 0.2-0.4mJy consistent with previous mid-infrared surveys with ISO and Spitzer at 15 and 24{mu}m. We compare our results with galaxy evolution models confirming the striking divergence from the non-evolving scenario. The models and observations are in broad agreement implying that the source counts are consistent with a strongly evolving population of luminous infrared galaxies at redshifts higher than unity. Integrating our source counts down to the limit of the NEP survey at the 150{mu}Jy level we calculate that AKARI has resolved approximately 55 per cent of the 18{mu}m cosmic infrared background relative to the predictions of contemporary source count models.
- ID:
- ivo://CDS.VizieR/J/ApJ/882/138
- Title:
- ALMA Spectroscopic Survey in the HUDF (ASPECS)
- Short Name:
- J/ApJ/882/138
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use the results from the ALMA large program ASPECS, the spectroscopic survey in the Hubble Ultra Deep Field (HUDF), to constrain CO luminosity functions of galaxies and the resulting redshift evolution of {rho}(H_2_). The broad frequency range covered enables us to identify CO emission lines of different rotational transitions in the HUDF at z>1. We find strong evidence that the CO luminosity function evolves with redshift, with the knee of the CO luminosity function decreasing in luminosity by an order of magnitude from ~2 to the local universe. Based on Schechter fits, we estimate that our observations recover the majority (up to ~90%, depending on the assumptions on the faint end) of the total cosmic CO luminosity at z=1.0-3.1. After correcting for CO excitation, and adopting a Galactic CO-to-H_2_ conversion factor, we constrain the evolution of the cosmic molecular gas density {rho}(H_2_): this cosmic gas density peaks at z~1.5 and drops by a factor of 6.5_-1.4_^+1.8^ to the value measured locally. The observed evolution in {rho}(H_2_), therefore, closely matches the evolution of the cosmic star formation rate density {rho}SFR. We verify the robustness of our result with respect to assumptions on source inclusion and/or CO excitation. As the cosmic star formation history can be expressed as the product of the star formation efficiency and the cosmic density of molecular gas, the similar evolution of {rho}(H_2_) and {rho}SFR leaves only little room for a significant evolution of the average star formation efficiency in galaxies since z~3 (85% of cosmic history).
- ID:
- ivo://CDS.VizieR/J/A+A/462/507
- Title:
- AMIGA III. IRAS data
- Short Name:
- J/A+A/462/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the mid- (MIR) and far- (FIR) infrared properties of a large (~1000) sample of the most isolated galaxies in the local Universe. This sample is intended as a "nurture-free" zero point against which more environmentally influenced samples can be compared. We reprocess IRAS MIR/FIR survey data using the ADDSCAN/SCANPI utility for 1030 out of 1050 galaxies from the Catalogue of Isolated Galaxies (CIG, Cat. <VII/82>) as part of the AMIGA survey. We focus on diagnostics (FIR luminosity LFIR , R=log(LFIR/LB) and IRAS colours) thought to be sensitive to effects of environment or interaction.
- ID:
- ivo://CDS.VizieR/J/ApJ/900/9
- Title:
- AMIGA: The Circumgalactic Medium of Andromeda
- Short Name:
- J/ApJ/900/9
- Date:
- 14 Mar 2022 07:38:05
- Publisher:
- CDS
- Description:
- Project AMIGA (Absorption Maps In the Gas of Andromeda) is a survey of the circumgalactic medium (CGM) of Andromeda (M31, R_vir_~300kpc) along 43 QSO sightlines at impact parameters 25<~R<~569kpc (25 at R<~R_vir_). We use ultraviolet absorption measurements of SiII, SiIII, SiIV, CII, and CIV from the Hubble Space Telescope/Cosmic Origins Spectrograph and OVI from the Far Ultraviolet Spectroscopic Explorer to provide an unparalleled look at how the physical conditions and metals are distributed in the CGM of M31. We find that SiIII and OVI have a covering factor near unity for R<~1.2R_vir_ and <~1.9R_vir_, respectively, demonstrating that M31 has a very extended ~104-105.5K ionized CGM. The metal and baryon masses of the 104-105.5K CGM gas within R_vir_ are >~108 and >~4x1010 (Z/0.3Z{sun})-1M{sun}, respectively. There is not much azimuthal variation in the column densities or kinematics, but there is with R. The CGM gas at R<~0.5R_vir_ is more dynamic and has more complicated, multiphase structures than at larger radii, perhaps a result of more direct impact of galactic feedback in the inner regions of the CGM. Several absorbers are projected spatially and kinematically close to M31 dwarf satellites, but we show that those are unlikely to give rise to the observed absorption. Cosmological zoom simulations of ~L* galaxies have OVI extending well beyond R_vir_ as observed for M31 but do not reproduce well the radial column density profiles of the lower ions. However, some similar trends are also observed, such as the lower ions showing a larger dispersion in column density and stronger dependence on R than higher ions. Based on our findings, it is likely that the Milky Way has a ~104-105.5K CGM as extended as for M31 and their CGM (especially the warm-hot gas probed by OVI) are overlapping.
- ID:
- ivo://CDS.VizieR/J/A+A/486/73
- Title:
- AMIGA VII. FIR and radio study
- Short Name:
- J/A+A/486/73
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper is part of a series involving the AMIGA project (Analysis of the Interstellar Medium of Isolated GAlaxies). This project provides a statistically-significant sample of the most isolated galaxies in the northern sky. We present a study of the nuclear activity in a well-defined sample of the most isolated galaxies (total sample: n=1050, complete subsample: n=719) in the local Universe traced by their far-infrared (FIR) and radio continuum emission. We use the well-known radio continuum-FIR correlation to select radio-excess galaxies that are candidates to host an active galactic nucleus (AGN), as well as the FIR colours to find obscured AGN-candidates. We also used the existing information on nuclear activity in the Veron-Cetty catalogue and in the NASA Extragalactic Database. A final catalogue of AGN-candidate galaxies has been produced that will provide a baseline for studies on the dependence of activity on the environment. Our sample is mostly radio quiet, consistent with its high content of late-type galaxies. At most ~1.5% of the galaxies show a radio excess with respect to the radio-FIR correlation, and this fraction even goes down to less than 0.8% after rejection of back/foreground sources using FIRST. We find that the fraction of FIR colour selected AGN-candidates is ~28% with a lower limit of ~7%. Our final catalogue contains 89 AGN candidates and is publicly available on the AMIGA web page (http://www.iaa.csic.es/AMIGA.html).
- ID:
- ivo://CDS.VizieR/J/A+A/613/A72
- Title:
- AS1063 and MACS1206-08 datacubes
- Short Name:
- J/A+A/613/A72
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results from the KMOS LENsing Survey (KLENS), which is exploiting gravitational lensing to study the kinematics of 24 star-forming galaxies at 1.4<z<3.5 with a median mass of log(M*/M_{sun}_)=9.6 and a median star formation rate (SFR) of 7.5M_{sun}/yr. We find that 25% of these low mass/low SFR galaxies are rotation-dominated, while the majority of our sample shows no velocity gradient. When combining our data with other surveys, we find that the fraction of rotation-dominated galaxies increases with the stellar mass, and decreases for galaxies with a positive offset from the main sequence (higher specific star formation rate). We also investigate the evolution of the intrinsic velocity dispersion, sigma_0_, as a function of the redshift, z, and stellar mass, M*, assuming galaxies in quasi-equilibrium (Toomre Q parameter equal to 1). From the z-sigma_0_ relation, we find that the redshift evolution of the velocity dispersion is mostly expected for massive galaxies (log(M*/M_{sun}_)>10). We derive a M*-sigma_0_ relation, using the Tully-Fisher relation, which highlights that a different evolution of the velocity dispersion is expected depending on the stellar mass, with lower velocity dispersions for lower masses, and an increase for higher masses, stronger at higher redshift. The observed velocity dispersions from this work and from comparison samples spanning 0<z<3.5 appear to follow this relation, except at higher redshift (z>2), where we observe higher velocity dispersions for low masses (log(M*/M_{sun}_)~9.6) and lower velocity dispersions for high masses (log(M*/M_{sun}_)~10.9) than expected. This discrepancy could, for instance, suggest that galaxies at high redshift do not satisfy the stability criterion, or that the adopted parametrization of the specific star formation rate and molecular properties fail at high redshift.
- ID:
- ivo://CDS.VizieR/J/ApJS/244/24
- Title:
- A z=0 Multiwavelength Galaxy Synthesis (z0MGS). I.
- Short Name:
- J/ApJS/244/24
- Date:
- 14 Mar 2022 07:45:54
- Publisher:
- CDS
- Description:
- We present an atlas of ultraviolet and infrared images of ~15750 local (d<~50Mpc) galaxies, as observed by NASA's Wide-field Infrared Survey Explorer (WISE) and Galaxy Evolution Explorer (GALEX) missions. These maps have matched resolution (FWHM 7.5" and 15"), matched astrometry, and a common procedure for background removal. We demonstrate that they agree well with resolved intensity measurements and integrated photometry from previous surveys. This atlas represents the first part of a program (the z=0 Multiwavelength Galaxy Synthesis) to create a large, uniform database of resolved measurements of gas and dust in nearby galaxies. This atlas allows us estimate local and integrated star formation rates (SFRs) and stellar masses (M_*_) across the local galaxy population in a uniform way. In the appendix, we use the population synthesis fits of Salim+ (2016ApJS..227....2S and 2018ApJ...859...11S) to calibrate integrated M_*_ and SFR estimators based on GALEX and WISE. Because they leverage a Sloan Digital Sky Survey (SDSS)-based training set of >100000 galaxies, these calibrations have high precision and allow us to rigorously compare local galaxies to SDSS results. We provide these SFR and M_*_ estimates for all galaxies in our sample and show that our results yield a "main sequence" of star-forming galaxies comparable to previous work. We also show the distribution of intensities from resolved galaxies in NUV-to-WISE1 versus WISE1-to-WISE3 space, which captures much of the key physics accessed by these bands.
- ID:
- ivo://CDS.VizieR/J/A+A/621/A60
- Title:
- Bright nearby elliptical gal. Xshooter spectra
- Short Name:
- J/A+A/621/A60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A new generation of spectral synthesis models has been developed in the recent years, but there is no matching -- in terms of quality and resolution -- set of template galaxy spectra for testing and refining the new models. Our main goal is to find and calibrate new near-infrared spectral indices along the Hubble sequence of galaxies which will be used to obtain additional constraints to the population analysis based on medium resolution integrated spectra of galaxies. Spectra of previously studied and well understood galaxies with relatively simple stellar populations (e.g., ellipticals or bulge dominated galaxies) are needed to provide a baseline data set for spectral synthesis models. X-Shooter spectra spanning the optical and infrared wavelength (350-2400nm) of bright nearby elliptical galaxies with resolving power R~4000-5400 were obtained. Heliocentric systemic velocity, velocity dispersion and Mg, Fe and H{beta} line-strength indices are presented. We present a library of very high quality spectra of galaxies covering a large range of age, metallicity and morphological type. Such as a dataset of spectra will be crucial to address important questions of the modern investigation concerning galaxy formation and evolution.
- ID:
- ivo://CDS.VizieR/J/A+A/382/60
- Title:
- BVR photometry in Abell 1689
- Short Name:
- J/A+A/382/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- At a redshift of 0.18, Abell 1689 is so far the most distant cluster of galaxies for which substantial mid-infrared (MIR) data have been published. Its mapping with the ISOCAM camera onboard the ISO satellite allowed the detection of 30 cluster members at 6.75{mu}m (LW2 filter) and 16 cluster members at 15{mu}m (LW3 filter) within a clustercentric radius of 0.5Mpc (Fadda et al., 2000A&A...361..827F, Paper I). We present here the follow-up optical photometric and spectroscopic observations which were used to study the individual properties of the galaxy members of A1689. We confirm the high fraction of blue galaxies initially reported in this rich cluster by Butcher & Oemler (1984ApJ...285..426B), that was challenged by some subsequent studies. We discuss the spectral and morphological properties of all cluster members in our spectroscopic sample, and of the MIR-detected galaxies in particular.