- ID:
- ivo://CDS.VizieR/J/A+A/653/A74
- Title:
- Bootes field X-ray/non-X-ray sources
- Short Name:
- J/A+A/653/A74
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- We use X-ray active galactic nuclei (AGN) observed by the Chandra X-ray Observatory within the 9.3deg^2^ Bootes field of the NDWFS to study whether there is a correlation between X-ray luminosity (LX) and star formation rate (SFR) of the host galaxy, at 0.5<z<2.0, with respect to the position of the galaxy to the main sequence (SFRnorm). About half of the sources in the X-ray sample have spectroscopic redshifts. We also construct a reference galaxy catalogue. For both datasets we use photometric data from the optical to the far-infrared compiled by the HELP project, and apply spectral energy distribution (SED) fitting, using the X-CIGALE code. We exclude quiescent sources from both the X-ray and the reference samples. We also account for the mass completeness of our dataset, in different redshifts bins. Our analysis highlights the importance of studying the SFR-LX relation in a uniform manner, taking into account systematics and selection effects. Our results suggest, in less massive galaxies (log[M*(M_{sun}_)]~11), that an AGN enhances the SFR of the host galaxy by 50% compared to non-AGN systems. A flat relation is observed for the most massive galaxies. The SFRnorm does not evolve with redshift. The results, although tentative, are consistent with a scenario where, in less massive systems, both AGN and star formation are fed by cold gas supplied by a merger event. In more massive galaxies the flat relation could be explained by a different supermasssive black hole (SMBH) fuelling mechanism that is decoupled from the star formation of the host galaxy (e.g. hot diffuse gas). Finally, we compare the host galaxy properties of X-ray absorbed and unabsorbed sources. Our results show no difference, which suggests that X-ray absorption is not linked with the properties of the galaxy.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/471/629
- Title:
- Bootes-HiZELS. Em-line galaxies at z=0.4-4.7
- Short Name:
- J/MNRAS/471/629
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a sample of ~1000 emission-line galaxies at z=0.4-4.7 from the ~0.7deg^2^ High-z Emission-Line Survey in the Bootes field identified with a suite of six narrow-band filters at ~=0.4-2.1{mu}m. These galaxies have been selected on their Ly{alpha} (73), [OII] (285), H{beta}/[OIII] (387) or H{alpha} (362) emission line, and have been classified with optical to near-infrared colours. A subsample of 98 sources have reliable redshifts from multiple narrow-band (e.g. [OII]-H{alpha}) detections and/or spectroscopy. In this survey paper, we present the observations, selection and catalogues of emitters. We measure number densities of Ly{alpha}, [OII], H{beta}/[OIII] and H{alpha} and confirm strong luminosity evolution in star-forming galaxies from z~0.4 to ~5, in agreement with previous results. To demonstrate the usefulness of dual-line emitters, we use the sample of dual [OII]-H{alpha} emitters to measure the observed [OII]/H{alpha} ratio at z=1.47. The observed [OII]/H{alpha} ratio increases significantly from 0.40+/-0.01 at z=0.1 to 0.52+/-0.05 at z=1.47, which we attribute to either decreasing dust attenuation with redshift, or due to a bias in the (typically) fibre measurements in the local Universe that only measure the central kpc regions. At the bright end, we find that both the H{alpha} and Ly{alpha} number densities at z~=2.2 deviate significantly from a Schechter form, following a power law. We show that this is driven entirely by an increasing X-ray/active galactic nucleus fraction with line luminosity, which reaches ~=100 per cent at line luminosities L>=3x10^44^erg/s.
2023. Boo Void survey
- ID:
- ivo://CDS.VizieR/J/ApJ/314/493
- Title:
- Boo Void survey
- Short Name:
- J/ApJ/314/493
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In an earlier paper we inferred, from the distribution of galaxy redshifts in three small fields ~30{deg} apart, the existence of a 10^6^Mpc^3^ void in the distribution of galaxies in the constellation of Bootes. In this paper, we describe a redshift survey undertaken to test that hypothesis. Galaxies were selected by eye from 283 small fields distributed between the three original fields, and redshifts were measured for 239 of them. We confirm the existence of a large, roughly spherical void, of radius 62Mpc, centered at {alpha}=14h50, {delta}=+46{deg}, v=15500km/s. The low density of this region is of high statistical significance and does not appear easily reconcilable with any of the popular models for the growth of structure in the universe. This void does contain some unusual galaxies characterized by strong, high-excitation emission spectra, but not in sufficient numbers to compensate for the absence of more usual objects.
- ID:
- ivo://CDS.VizieR/I/228
- Title:
- Bordeaux AC Zone Data Reduced to ACRS
- Short Name:
- I/228
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The U.S. Naval Observatory is in the process of making new reductions of the Astrographic Catalogue (AC) using a modern reference system, the ACRS, which represents the system of the FK5. The data from the Bordeaux Zone, whose plates are centered between declinations +11 and +17 degrees (eq. 1900), have been analyzed for scale, rotation, tilt, coma, magnitude equation, radial distortion and distortions introduced by the use of reseaux in the Carte du Ciel program. The result is a positional catalog of over 223,000 stars on eq. J2000.0, epoch of observation. Additionally, all stars have been matched with the Tycho Input Catalog (revised); those numbers have been added for additional identification purposes.
- ID:
- ivo://CDS.VizieR/J/A+A/559/A100
- Title:
- Boron isoelectronic sequence data
- Short Name:
- J/A+A/559/A100
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Relativistic configuration interaction (RCI) calculations are performed for 291 states belonging to the configurations 1s^2^2s^2^2p, 1s^2^2s2p^2^, 1s^2^2p^3^, 1s^2^2s^2^3l, 1s^2^2s2p3l, 1s^2^2p^2^3l, 1s^2^2s^2^4l', 1s^2^2s2p4l', and 1s^2^2p^2^4l' (l=0, 1, 2 and l'=0, 1, 2, 3) in boronlike ions Si X and Ti XVIII to Cu XXV. Electron correlation effects are represented in the wave functions by large configuration state function (CSF) expansions. States are transformed from j j-coupling to LS -coupling, and the LS -percentage compositions are used for labeling the levels. Radiative electric dipole transition rates are given for all ions, leading to massive data sets. Calculated energy levels are compared with other theoretical predictions and crosschecked against the Chianti database, NIST recommended values, and other observations. The accuracy of the calculations are high enough to facilitate the identification of observed spectral lines.
- ID:
- ivo://CDS.VizieR/J/A+A/455/1157
- Title:
- Boron-like Fe XXII transition probabilities
- Short Name:
- J/A+A/455/1157
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Energy levels and the corresponding transition probabilities as well as oscillator strengths and line strengths for allowed (E1) and forbidden (E2, M1) transitions among the lowest 407 levels of boron-like Fe XXII are presented. Calculations were performed using the multiconfigurational Dirac-Fock GRASP code.
- ID:
- ivo://CDS.VizieR/J/MNRAS/463/1929
- Title:
- BOSS galaxies in X-ray clusters
- Short Name:
- J/MNRAS/463/1929
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a direct measurement of the mean halo occupation distribution (HOD) of galaxies taken from the eleventh data release (DR11) of the Sloan Digital Sky Survey-III Baryon Oscillation Spectroscopic Survey (BOSS). The HOD of BOSS low-redshift (LOWZ: 0.2<z<0.4) and Constant-Mass (CMASS: 0.43<z<0.7) galaxies is inferred via their association with the dark-matter halos of 174 X-ray-selected galaxy clusters drawn from the XMM Cluster Survey (XCS). Halo masses are determined for each galaxy cluster based on X-ray temperature measurements, and range between log_10_(M_180_/M_{sun}_)=13-15. Our directly measured HODs are consistent with the HOD-model fits inferred via the galaxy-clustering analyses of Parejko et al. for the BOSS LOWZ sample and White et al. for the BOSS CMASS sample. Under the simplifying assumption that the other parameters that describe the HOD hold the values measured by these authors, we have determined a best-fit alpha-index of 0.91+/-0.08 and 1.27^+0.03^_-0.04_ for the CMASS and LOWZ HOD, respectively. These alpha-index values are consistent with those measured by White et al. and Parejko et al. In summary, our study provides independent support for the HOD models assumed during the development of the BOSS mock-galaxy catalogues that have subsequently been used to derive BOSS cosmological constraints.
- ID:
- ivo://CDS.VizieR/J/MNRAS/418/1055
- Title:
- BOSS morphology of galaxies
- Short Name:
- J/MNRAS/418/1055
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the morphology and size of the luminous and massive galaxies at 0.3<z<0.7 targeted in the Baryon Oscillation Spectroscopic Survey (BOSS) using publicly available Hubble Space Telescope (HST) imaging, and catalogues, from the COSMic Origins Survey (COSMOS). Our sample (240 objects) provides a unique opportunity to check the visual morphology of these galaxies which were targeted based solely on stellar population modelling.
- ID:
- ivo://CDS.VizieR/J/MNRAS/462/2980
- Title:
- BOSS narrow CIV absorption lines. III.
- Short Name:
- J/MNRAS/462/2980
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we extend our work of IV {lambda}{lambda}1548,1551 narrow absorption lines (NALs) with z_abs_<<z_em_ on quasar spectra of the Baryon Oscillation Spectroscopic Survey (BOSS) to collect CIV NALs with z_abs_<=z_em_ from blue to red wings of CIV {lambda}1549 emission lines. Together with IV NALs with 1.4544<=z_abs_<=4.9224 in surveyed spectral region redward of Ly{alpha} until red wing of CIV {lambda}1549 emission line. We find that the stronger CIV NALs tend to be the more saturated absorptions, and associated systems (z_abs_~=z_em_) seem to have larger absorption strengths when compared to intervening ones (z_abs_<<z_em_). The redshift density evolution behaviour of absorbers (the number of absorbers per redshift path) is similar to the history of the cosmic star formation. When compared to the quasar-frame velocity ({beta}) distribution of MgII absorbers, the {beta} distribution of CIV absorbers is broader at {beta}~=0, shows longer extended tail, and exhibits a larger dispersion for environmental absorptions. In addition, for associated CIV absorbers, we find that low-luminosity quasars seem to exhibit smaller {beta} and stronger absorptions when compared to high-luminosity quasars.
- ID:
- ivo://CDS.VizieR/J/ApJS/215/12
- Title:
- BOSS narrow CIV absorption lines. II. zem>2.4
- Short Name:
- J/ApJS/215/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As the second work in a series of papers aiming to detect absorption systems in the quasar spectra of the Baryon Oscillation Spectroscopic Survey, we continue the analysis of Paper I (Chen+, 2014, J/ApJS/210/7; 2014ApJS..212...17C) by expanding the quasar sample to those quasars with z_em_>2.4. This yields a sample of 21963 appropriate quasars to search for narrow CIV{lambda}{lambda}1548,1551 absorptions with W_r_>=0.2{AA} for both lines. There are 9708 quasars with at least one appropriate absorption system imprinted on their spectra. From these spectra, we detect 13919 narrow C IV absorption systems whose absorption redshifts cover a range of z_abs_=1.8784-4.3704. In this paper and Paper I, we have selected 37241 appropriate quasars with median S/N>=4 and 1.54<~z_em_<~5.16 to visually analyze narrow CIV{lambda}{lambda}1548,1551 absorption doublets one by one. A total of 15999 quasars are found to have at least one appropriate absorption system imprinted on their spectra. From these 15999 quasar spectra, we have detected 23336 appropriate CIV{lambda}{lambda}1548,1551 absorption systems with W_r_>=0.2{AA} whose absorption redshifts cover a range of z_abs_=1.4544-4.3704. The largest values of W_r_ are 3.19{AA} for the {lambda}1548 absorption line and 2.93{AA} for the {lambda}1551 absorption line, respectively. We find that only a few absorbers show large values of W_r_. About 1.1% of the total absorbers have W_r_{lambda}1548>=2.0{AA}.
