- ID:
- ivo://CDS.VizieR/J/MNRAS/492/3073
- Title:
- CALIFA galaxies hosting an AGN
- Short Name:
- J/MNRAS/492/3073
- Date:
- 02 Feb 2022 07:33:25
- Publisher:
- CDS
- Description:
- We study the presence of optically-selected Active Galactic Nuclei (AGNs) within a sample of 867 galaxies extracted from the extended Calar-Alto Legacy Integral Field spectroscopy Area (eCALIFA) spanning all morphological classes. We identify 10 Type-I and 24 Type-II AGNs, amounting to ~4 per cent of our sample, similar to the fraction reported by previous explorations in the same redshift range. We compare the integrated properties of the ionized and molecular gas, and stellar population of AGN hosts and their non-active counterparts, combining them with morphological information. The AGN hosts are found in transitory parts (i.e. green-valley) in almost all analysed properties which present bimodal distributions (i.e. a region where reside star-forming galaxies and another with quiescent/retired ones). Regarding morphology, we find AGN hosts among the most massive galaxies, with enhanced central stellar-mass surface density in comparison to the average population at each morphological type. Moreover, their distribution peaks at the Sab-Sb classes and none are found among very late-type galaxies (>Scd). Finally, we inspect how the AGN could act in heir hosts regarding the quenching of star-formation. The main role of the AGN in the quenching process appears to be the removal (or heating) of molecular gas, rather than an additional suppression of the already observed decrease of the star-formation efficiency from late-to-early type galaxies.
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- ID:
- ivo://CDS.VizieR/J/A+A/604/A4
- Title:
- CALIFA galaxies observational hints
- Short Name:
- J/A+A/604/A4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- According to numerical simulations, stars are not always kept at their birth galactocentric distances but migrate. The importance of this radial migration in shaping galactic light distributions is still unclear. However, if it is indeed important, galaxies with different surface brightness (SB) profiles must display differences in their stellar population properties. We investigate the role of radial migration on the light distribution and the radial stellar content by comparing the inner colour, age and metallicity gradients for galaxies with different SB profiles. We define these inner parts avoiding the bulge and bar regions and up to around three disc scale lengths (type I, pure exponential) or the break radius (type II, downbending; type III, upbending). We analyse 214 spiral galaxies from the CALIFA survey covering different SB profiles. We make use of GASP2D and SDSS data to characterise their light distribution and obtain colour profiles. The stellar age and metallicity profiles are computed using a methodology based on full-spectrum fitting techniques (pPXF, GANDALF, and STECKMAP) to the IFS CALIFA data. The distributions of the colour, stellar age and stellar metallicity gradients in the inner parts for galaxies displaying different SB profiles are unalike as suggested by Kolmogorov-Smirnov and Anderson-Darling tests. We find a trend in which type II galaxies show the steepest profiles of all and type III the shallowest, with type I galaxies displaying an intermediate behaviour. These results are consistent with a scenario in which radial migration is more efficient for type III galaxies than for type I systems with type II galaxies presenting the lowest radial migration efficiency. In such scenario, radial migration mixes the stellar content flattening the radial stellar properties and shaping different SB profiles. However, in sight of these results we cannot further quantify its importance in shaping spiral galaxies, and other processes such as recent star formation or satellite accretion might play a role.
- ID:
- ivo://CDS.VizieR/J/A+A/584/A87
- Title:
- CALIFA sample SFR calibration
- Short Name:
- J/A+A/584/A87
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The star formation rate (SFR) is one of the main parameters used to analyze the evolution of galaxies through time. The need for recovering the light reprocessed by dust commonly requires the use of low spatial resolution far-infrared data. Recombination line luminosities provide an alternative, although uncertain dust-extinction corrections based on narrowband imaging or long-slit spectroscopy have traditionally posed a limit to their applicability. Integral field spectroscopy (IFS) is clearly the way to overcome this kind of limitation. We obtain integrated H{alpha}, ultraviolet (UV) and infrared (IR)-based SFR measurements for 272 galaxies from the CALIFA survey at 0.005<z<0.03 using single-band and hybrid tracers. We aim to determine whether the extinction-corrected H{alpha} luminosities provide a good measure of the SFR and to shed light on the origin of the discrepancies between tracers. Updated calibrations referred to H{alpha} are provided. The well-defined selection criteria and large statistics allow us to carry out this analysis globally and split by properties, including stellar mass and morphological type. We derive integrated, extinction-corrected H{alpha} fluxes from CALIFA, UV surface and asymptotic photometry from GALEX and integrated WISE 22{mu}m and IRAS fluxes. We find that the extinction-corrected H{alpha} luminosity agrees with the hybrid updated SFR estimators based on either UV or H{alpha} plus IR luminosity over the full range of SFRs (0.03-20M_{sun}_/yr). The coefficient that weights the amount of energy produced by newly-born stars that is reprocessed by dust on the hybrid tracers, a_IR_, shows a large dispersion. However, this coefficient does not became increasingly small at high attenuations, as expected if significant highly-obscured H{alpha} emission were missed, i.e., after a Balmer decrement-based attenuation correction is applied. Lenticulars, early-type spirals, and type-2 AGN host galaxies show smaller coefficients because of the contribution of optical photons and AGN to dust heating. In the local Universe, the H{alpha} luminosity derived from IFS observations can be used to measure SFR, at least in statistically-significant, optically-selected galaxy samples, once stellar continuum absorption and dust attenuation effects are accounted for. The analysis of the SFR calibrations by galaxies properties could potentially be used by other works to study the impact of different selection criteria in the SFR values derived, and to disentangle selection effects from other physically motivated differences, such as environmental or evolutionary effects.
- ID:
- ivo://CDS.VizieR/J/AJ/156/264
- Title:
- California-Kepler Survey. VII. Planet radius gap
- Short Name:
- J/AJ/156/264
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The distribution of planet sizes encodes details of planet formation and evolution. We present the most precise planet size distribution to date based on Gaia parallaxes, Kepler photometry, and spectroscopic temperatures from the California-Kepler Survey. Previously, we measured stellar radii to 11% precision using high-resolution spectroscopy; by adding Gaia astrometry, the errors are now 3%. Planet radius measurements are, in turn, improved to 5% precision. With a catalog of ~1000 planets with precise properties, we probed in fine detail the gap in the planet size distribution that separates two classes of small planets, rocky super-Earths and gas-dominated sub-Neptunes. Our previous study and others suggested that the gap may be observationally under-resolved and inherently flat-bottomed, with a band of forbidden planet sizes. Analysis based on our new catalog refutes this; the gap is partially filled in. Two other important factors that sculpt the distribution are a planet's orbital distance and its host-star mass, both of which are related to a planet's X-ray/UV irradiation history. For lower-mass stars, the bimodal planet distribution shifts to smaller sizes, consistent with smaller stars producing smaller planet cores. Details of the size distribution including the extent of the "sub-Neptune desert" and the width and slope of the gap support the view that photoevaporation of low-density atmospheres is the dominant evolutionary determinant of the planet size distribution.
935. CALYMHA survey. I.
- ID:
- ivo://CDS.VizieR/J/MNRAS/466/1242
- Title:
- CALYMHA survey. I.
- Short Name:
- J/MNRAS/466/1242
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the CAlibrating LYMan-{alpha} with H{alpha} (CALYMHA) pilot survey and new results on Lyman {alpha} (Ly{alpha}) selected galaxies at z~2. We use a custom-built Ly{alpha} narrow-band filter at the Isaac Newton Telescope, designed to provide a matched volume coverage to the z=2.23H{alpha} HiZELS survey. Here, we present the first results for the COSMOS and UDS fields. Our survey currently reaches a 3{sigma} line flux limit of ~4x10^-17^erg/s/cm^2^, and a Ly{alpha} luminosity limit of ~10^42.3^erg/s. We find 188 Ly{alpha} emitters over 7.3x10^5^Mpc^3^, but also find significant numbers of other line-emitting sources corresponding to HeII, CIII] and CIV emission lines. These sources are important contaminants, and we carefully remove them, unlike most previous studies. We find that the Ly{alpha} luminosity function at z=2.23 is very well described by a Schechter function up to L_Ly{alpha}_~=10^43^erg/s^ with L*=10^42.59(10^42.75^-10^42.01^)erg/s, {phi}*=10^-3.09^(10^-3.43^-10^2.95)Mpc^-3^ and {alpha}=-1.75+/-0.25. Above L_Ly{alpha}_~=10^43^erg/s, the Ly{alpha} luminosity function becomes power-law like, driven by X-ray AGN. We find that Ly{alpha}-selected emitters have a high escape fraction of 37+/-7 per cent, anticorrelated with Ly{alpha} luminosity and correlated with Ly{alpha} equivalent width. Ly{alpha} emitters have ubiquitous large (~=40kpc) Ly{alpha} haloes, ~2 times larger than their H{alpha} extents. By directly comparing our Ly{alpha} and H{alpha} luminosity functions, we find that the global/overall escape fraction of Ly{alpha} photons (within a 13kpc radius) from the full population of star-forming galaxies is 5.1+/-0.2 per cent at the peak of the star formation history. An extra 3.3+/-0.3 per cent of Ly{alpha} photons likely still escape, but at larger radii.
- ID:
- ivo://CDS.VizieR/J/BaltA/16/327
- Title:
- Camelopardalis dust and molecular clouds
- Short Name:
- J/BaltA/16/327
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using infrared photometric data extracted from the 2MASS, IRAS and MSX databases, 142 suspected young stellar objects (YSOs) are selected from about 2 million stars in the Camelopardalis segment of the Milky Way limited by Galactic coordinates, b=132-158{deg},+/-12{deg}.
- ID:
- ivo://CDS.VizieR/J/ApJS/206/10
- Title:
- CANDELS multiwavelength catalog
- Short Name:
- J/ApJS/206/10
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the multiwavelength ultraviolet to mid-infrared catalog of the UKIRT Infrared Deep Sky Survey (UKIDSS) Ultra-Deep Survey field observed as part of the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS). Based on publicly available data, the catalog includes the CANDELS data from the Hubble Space Telescope (near-infrared WFC3 F125W and F160W data and visible ACS F606W and F814W data); u-band data from CFHT/Megacam; B, V, Rc, i', and z' band data from Subaru/Suprime-Cam; Y and Ks band data from VLT/HAWK-I; J, H, and K band data from UKIDSS (Data Release 8); and Spitzer/IRAC data (3.6, 4.5um from SEDS; 5.8 and 8.0um from SpUDS). The present catalog is F160W-selected and contains 35932 sources over an area of 201.7arcmin^2^ and includes radio- and X-ray-detected sources and spectroscopic redshifts available for 210 sources.
- ID:
- ivo://CDS.VizieR/J/ApJS/229/32
- Title:
- CANDELS: multiwavelength catalogs in the EGS
- Short Name:
- J/ApJS/229/32
- Date:
- 03 Nov 2021 09:14:43
- Publisher:
- CDS
- Description:
- We present a 0.4-8{mu}m multi-wavelength photometric catalog in the Extended Groth Strip (EGS) field. This catalog is built on the Hubble Space Telescope (HST) WFC3 and ACS data from the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS), and it incorporates the existing HST data from the All-wavelength Extended Groth strip International Survey (AEGIS) and the 3D-HST program. The catalog is based on detections in the F160W band reaching a depth of F160W=26.62 AB (90% completeness, point sources). It includes the photometry for 41457 objects over an area of ~206arcmin^2^ in the following bands: HST/ACS F606W and F814W; HST WFC3 F125W, F140W, and F160W; Canada-France-Hawaii Telescope (CFHT)/Megacam u*, g' , r', i' and z'; CFHT/WIRCAM J, H, and K_S_; Mayall/NEWFIRM J1, J2, J3, H1, H2, and K; Spitzer IRAC 3.6, 4.5, 5.8, and 8.0{mu}m. We are also releasing value-added catalogs that provide robust photometric redshifts and stellar mass measurements.
- ID:
- ivo://CDS.VizieR/J/ApJS/221/11
- Title:
- CANDELS visual classifications for GOODS-S
- Short Name:
- J/ApJS/221/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have undertaken an ambitious program to visually classify all galaxies in the five CANDELS fields down to H<24.5 involving the dedicated efforts of over 65 individual classifiers. Once completed, we expect to have detailed morphological classifications for over 50000 galaxies spanning 0<z<4 over all the fields, with classifications from 3 to 5 independent classifiers for each galaxy. Here, we present our detailed visual classification scheme, which was designed to cover a wide range of CANDELS science goals. This scheme includes the basic Hubble sequence types, but also includes a detailed look at mergers and interactions, the clumpiness of galaxies, k-corrections, and a variety of other structural properties. In this paper, we focus on the first field to be completed --GOODS-S, which has been classified at various depths. The wide area coverage spanning the full field (wide+deep+ERS) includes 7634 galaxies that have been classified by at least three different people. In the deep area of the field, 2534 galaxies have been classified by at least five different people at three different depths. With this paper, we release to the public all of the visual classifications in GOODS-S along with the Perl/Tk GUI that we developed to classify galaxies. We present our initial results here, including an analysis of our internal consistency and comparisons among multiple classifiers as well as a comparison to the Sersic index. We find that the level of agreement among classifiers is quite good (>70% across the full magnitude range) and depends on both the galaxy magnitude and the galaxy type, with disks showing the highest level of agreement (>50%) and irregulars the lowest (<10%). A comparison of our classifications with the Sersic index and rest-frame colors shows a clear separation between disk and spheroid populations. Finally, we explore morphological k-corrections between the V-band and H-band observations and find that a small fraction (84 galaxies in total) are classified as being very different between these two bands. These galaxies typically have very clumpy and extended morphology or are very faint in the V-band.
- ID:
- ivo://CDS.VizieR/J/ApJ/793/101
- Title:
- CANDELS z~2 galaxy properties
- Short Name:
- J/ApJ/793/101
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use CANDELS imaging, 3D-HST spectroscopy, and Chandra X-ray data to investigate if active galactic nuclei (AGNs) are preferentially fueled by violent disk instabilities funneling gas into galaxy centers at 1.3<z<2.4. We select galaxies undergoing gravitational instabilities using the number of clumps and degree of patchiness as proxies. The CANDELS visual classification system is used to identify 44 clumpy disk galaxies, along with mass-matched comparison samples of smooth and intermediate morphology galaxies. We note that despite being mass-matched and having similar star formation rates, the smoother galaxies tend to be smaller disks with more prominent bulges compared to the clumpy galaxies. The lack of smooth extended disks is probably a general feature of the z~2 galaxy population, and means we cannot directly compare with the clumpy and smooth extended disks observed at lower redshift. We find that z~2 clumpy galaxies have slightly enhanced AGN fractions selected by integrated line ratios (in the mass-excitation method), but the spatially resolved line ratios indicate this is likely due to extended phenomena rather than nuclear AGNs. Meanwhile, the X-ray data show that clumpy, smooth, and intermediate galaxies have nearly indistinguishable AGN fractions derived from both individual detections and stacked non-detections. The data demonstrate that AGN fueling modes at z~1.85 - whether violent disk instabilities or secular processes - are as efficient in smooth galaxies as they are in clumpy galaxies.
