Citation for published item:intongeD em¡ elie nd gtinellD frr nd oniD vind tF nd uu'mnnD quinevere nd qenzelD einhrd nd gorteseD vu nd hv¡ eD omeel nd pletherD homs tF nd qri¡ EgrpioD tvier nd urmerD grsten nd rekmnD imothy wF nd tnowiekiD teven nd vutzD uthrin nd osrioD hvid nd himinovihD hvid nd husterD url nd ngD ting nd uytsD tijn nd forthkurD nhyeet nd vmpertiD ssell nd oertsEforsniD quido F @PHIUA 9xgyvh qe X the omplete sew QH m legy survey of moleulr gs for glxy evolution studiesF9D estrophysil journl supplement seriesFD PQQ @PAF pF PPF Further information on publisher's website: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. AbstractWe introduce xCOLD GASS, a legacy survey providing a census of molecular gas in the local universe. Building on the original COLD GASS survey, we present here the full sample of 532 galaxies with CO (1-0) measurements from the IRAM 30 m telescope. The sample is mass-selected in the redshift interval z 0.01 0.05 < < from the Sloan Digital Sky Survey (SDSS) and therefore representative of the local galaxy population with M M 10 9 * >  . The CO (1-0) flux measurements are complemented by observations of the CO (2-1) line with both the IRAM 30 m and APEX telescopes, H I observations from Arecibo, and photometry from SDSS, WISE, and GALEX. Combining the IRAM and APEX data, we find that the ratio of CO (2-1) to CO (1-0) luminosity for integrated measurements is r 0.79 0.03 21 =  , with no systematic variations across the sample. The CO (1-0) luminosity function is constructed and best fit with a Schechter function with parameters L 7.77 2.11 10 K km s pc 9 M  , we are able to extend our study of gas scaling relations and confirm that both molecular gas fractions ( f H 2 ) and depletion timescale (t H dep 2 ( )) vary with specific star formation rate (or offset from the star formation main sequence) much more strongly than they depend on stellar mass. Comparing the xCOLD GASS results with outputs from hydrodynamic and semianalytic models, we highlight the constraining power of cold gas scaling relations on models of galaxy formation.

Hard X-ray (10 keV) observations of active galactic nuclei (AGNs) can shed light on some of the most obscured episodes of accretion onto supermassive black holes. The 70-month Swift/BAT all-sky survey, which probes the 14-195 keV energy range, has currently detected 838 AGNs. We report here on the broadband X-ray (0.3-150 keV) characteristics of these AGNs, obtained by combining XMM-Newton, Swift/XRT, ASCA, Chandra, and Suzaku observations in the soft X-ray band ( 10  keV) with 70-month averaged Swift/BAT data. The nonblazar AGNs of our sample are almost equally divided into unobscured (N 10 cm H 22 2 < -) and obscured (N 10 cm H 22 2  -) AGNs, and their Swift/BAT continuum is systematically steeper than the 0.3-10 keV emission, which suggests that the presence of a high-energy cutoff is almost ubiquitous. We discuss the main X-ray spectral parameters obtained, such as the photon index, the reflection parameter, the energy of the cutoff, neutral and ionized absorbers, and the soft excess for both obscured and unobscured AGNs.

The large majority of the accreting supermassive black holes in the Universe are obscured by large columns of gas and dust [1][2][3] . The location and evolution of this obscuring material have been the subject of intense research in the past decades 4,5 , and are still highly debated. A decrease in the covering factor of the circumnuclear material with increasing accretion rates has been found by studies carried out across the electromagnetic spectrum 1,[6][7][8] . The origin of this trend has been suggested to be driven either by the increase in the inner radius of the obscuring material with incident luminosity due to the sublimation of dust 9 ; by the gravitational potential of the black hole 10 ; by radiative feedback [11][12][13][14] ; or by the interplay between outflows and inflows 15 . However, the lack of a large, unbiased and complete sample of accreting black holes, with reliable information on gas column density, luminosity and mass, has left the main physical mechanism regulating obscuration unclear. Using a systematic multi-wavelength survey of hard X-ray-selected black holes, here we show that radiation pressure on dusty gas is indeed the main physical mechanism regulating the distribution of the circumnuclear material. Our results imply that the bulk of the obscuring dust and gas in these objects is located within the sphere of influence of the black hole (i.e., a few to tens of parsecs), and that it can be swept away even at low radiative output rates. The main physical driver of the differences between obscured and unobscured accreting black holes is therefore their mass-normalized accretion rate.Our group has carried out a large multi-wavelength study of the 836 accreting supermassive black holes (i.e., active galactic nuclei or AGN) detected by the all-sky hard X-ray (14-195 keV) Swift Burst Alert Telescope survey 16, 17 (see §1 of the Methods). The energy range covered by Swift/BAT makes it ideal for studying the characteristics and evolu- Figure 1: Relation between the fraction of obscured AGN and the Eddington ratio. The fraction of obscured Compton-thin [10 22 ≤ (NH/cm −2 ) < 10 24 ] sources shown as a function of the Eddington ratio λ Edd (i.e. the AGN luminosity normalized by the maximum value for solar-metalicity, fully-ionized, dust-free gas in a spherical geometry) for our hard X-ray selected sample in the 10 −5.6 ≤ λ Edd < 1 range. The values are normalized to unity in the 10 20 ≤ (NH/cm −2 ) < 10 24 interval. The shaded area represents the 16th and 84th quantiles of a binomial distribution 20 . The vertical red dashed line represents the effective Eddington limit for a dusty gas 14 with NH = 10 22 cm −2 (see §2). The figure shows that the covering factor of the obscuring material with 10 22 ≤ (NH/cm −2 ) < 10 24 decreases sharply around the Eddington limit for dusty gas, highlighting the fact that radiation pressure strongly affects obscuration in AGN.tion of the absorbing material surrounding the AGN, being unaffected by obscuration up to column densities NH ≃ 10 24 cm −2 . More...

We present the first catalog and data release of the Swift-BAT AGN Spectroscopic Survey. We analyze optical spectra of the majority of the detected AGNs (77%, 642/836)based on their 14-195 keV emission in the 70-month Swift-BATall-sky catalog. This includes redshift determination, absorption and emission-line measurements, and black hole mass and accretion rate estimates for the majority of obscured and unobscured AGNs (74%, 473/642), with 340 measured for the first time. With ∼90% of sources at < z 0.2, the survey represents a significant advance in the census of hard X-ray-selected AGNs in the local universe. In this first catalog paper, we describe the spectroscopic observations and data sets, and our initial spectral analysis. The FWHMs of the emission lines show broad agreement with the X-ray obscuration (∼94%), such that Sy 1-1.8 have < N 10 H 21.9 cm −2 , and Seyfert 2 have > N 10 H 21.9 cm −2 . Seyfert 1.9, however, show a range of column densities. Compared to narrow-line AGNs in the SDSS, the X-ray-selected AGNs have a larger fraction of dusty host galaxies ( a b > H H 5), suggesting that these types of AGN are missed in optical surveys. Using the [O III] λ5007/Hβ and [N II] λ6583/Hα emission-line diagnostic, about half of the sources are classified as Seyferts; ∼15% reside in dusty galaxies that lack an Hβ detection, but for which the upper limits on line emission imply either a Seyfert or LINER,~15% are in galaxies with weak or no emission lines despite high-quality spectra, and a few percent each are LINERS, composite galaxies, H II regions, or in known beamed AGNs.

We present a new metric that uses the spectral curvature (SC) above 10 keV to identify Compton-thick AGN in low-quality Swift/BAT X-ray data. Using NuSTAR, we observe nine high SC-selected AGN. We find that high-sensitivity spectra show the majority are Compton-thick (78% or 7/9) and the remaining two are nearly Compton-thick (N H 5 − 8 × 10 23 cm −2 ). We find the SC BAT and SC NuSTAR measurements are consistent, suggesting this technique can be applied to future telescopes. We tested the SC method on wellknown Compton-thick AGN and find it is much more effective than broad band ratios (e.g. 100% using SC vs. 20% using 8-24/3-8 keV). Our results suggest that using the > 10 keV emission may be the only way to identify this population since only two sources show Compton-thick levels of excess in the Balmer decrement corrected [O III] to observed X-ray emission ratio (F [O III] /F obs 2−10 keV > 1) and WISE colors do not identify most of them as AGN. Based on this small sample, we find that a higher fraction of these AGN are in the final merger stage (<10 kpc) than typical BAT AGN. Additionally, these nine obscured AGN have, on average, ≈ 4× higher accretion rates than other BAT-detected AGN ( λ Edd = 0.068 ± 0.023 compared to λ Edd = 0.016 ± 0.004). The robustness of SC at identifying Compton-thick AGN implies a higher fraction of nearby AGN may be Compton-thick (≈ 22%) and the sum of black hole growth in Compton-thick AGN (Eddington ratio times population percentage), is nearly as large as mildly obscured and unobscured AGN.