- ID:
- ivo://CDS.VizieR/J/ApJS/217/2
- Title:
- Refined associations of Fermi/LAT sources
- Short Name:
- J/ApJS/217/2
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Fermi-Large Area Telescope (LAT) First Source Catalog (1FGL) was released in 2010 February and the Fermi-LAT 2-Year Source Catalog (2FGL) appeared in 2012 April, based on data from 24 months of operation. Since they were released, many follow up observations of unidentified {gamma}-ray sources have been performed and new procedures for associating {gamma}-ray sources with potential counterparts at other wavelengths have been developed. Here we review and characterize all of the associations as published in the 1FGL and 2FGL catalogs on the basis of multifrequency archival observations. In particular, we located 177 spectra for the low-energy counterparts that were not listed in the previous Fermi catalogs, and in addition we present new spectroscopic observations of eight {gamma}-ray blazar candidates. Based on our investigations, we introduce a new counterpart category of "candidate associations" and propose a refined classification for the candidate low-energy counterparts of the Fermi sources. We compare the 1FGL-assigned counterparts with those listed in 2FGL to determine which unassociated sources became associated in later releases of the Fermi catalogs. We also search for potential counterparts to all of the remaining unassociated Fermi sources. Finally, we prepare a refined and merged list of all of the associations of 1FGL plus 2FGL that includes 2219 unique Fermi objects. This is the most comprehensive and systematic study of all the associations collected for the {gamma}-ray sources available to date. We conclude that 80% of the Fermi sources have at least one known plausible {gamma}-ray emitter within their positional uncertainty regions.
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- ID:
- ivo://CDS.VizieR/J/A+A/499/357
- Title:
- REFLEX galaxies redshifts
- Short Name:
- J/A+A/499/357
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final data from the spectroscopic survey of the ROSAT-ESO Flux-Limited X-ray (REFLEX) catalogue of galaxy clusters. The REFLEX survey covers 4.24 steradians (34% of the entire sky) below a declination +2.50{deg} and at high galactic latitude (|b|<20{deg}). The full survey includes 447 galaxy clusters with a median redshift of 0.08 and is better than 90% complete to a limiting flux of f_X_=3x10^-12^ergs/s/cm^2^ (3fW/m^2^, 0.1 to 2.4keV), representing the largest statistically homogeneous sample of clusters to date drawn from the ROSAT All-Sky Survey (RASS). Here we describe the details of the spectroscopic observations carried out at the ESO 1.5m, 2.2m and 3.6m telescopes, the data reduction and redshift measurements techniques. The spectra typically cover the wavelength range 3600-7500{AA} at a two-pixel resolution of ~14{AA} . From calibrations and external checks the redshifts are accurate to a typical rms error of +/-100km/s.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A30
- Title:
- REFLEX II. Properties of the survey
- Short Name:
- J/A+A/555/A30
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Galaxy clusters provide unique laboratories to study astrophysical processes on large scales and are important probes for cosmology. X-ray observations are currently the best means of detecting and characterizing galaxy clusters. Therefore X-ray surveys for galaxy clusters are one of the best ways to obtain a statistical census of the galaxy cluster population. In this paper we describe the construction of the REFLEX II galaxy cluster survey based on the southern part of the ROSAT All-Sky Survey. REFLEX II extends the REFLEX I survey by a factor of about two down to a flux limit of 1.8x10^-12^erg/s/cm^2^ (0.1-2.4keV). We describe the determination of the X-ray parameters, the process of X-ray source identification, and the construction of the survey selection function. The REFLEX II cluster sample comprises currently 915 objects. A standard selection function is derived for a lower source count limit of 20 photons in addition to the flux limit. The median redshift of the sample is z=0.102. Internal consistency checks and the comparison to several other galaxy cluster surveys imply that REFLEX II is better than 90% complete with a contamination less than 10%. With this publication we give a comprehensive statistical description of the REFLEX II survey and provide all the complementary information necessary for a proper modelling of the survey for astrophysical and cosmological applications.
- ID:
- ivo://CDS.VizieR/J/ApJ/848/56
- Title:
- Relationships between SNe Ia and the host galaxies
- Short Name:
- J/ApJ/848/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a sample of 1338 spectroscopically confirmed and photometrically classified Type Ia supernovae (SNe Ia) sourced from Carnegie Supernova Project, Center for Astrophysics Supernova Survey, Sloan Digital Sky Survey-II, and SuperNova Legacy Survey SN samples to examine the relationships between SNe Ia and the galaxies that host them. Our results provide confirmation with improved statistical significance that SNe Ia, after standardization, are on average more luminous in massive hosts (significance >5{sigma}), and decline more rapidly in massive hosts (significance >9{sigma}) and in hosts with low specific star formation rates (significance >8{sigma}). We study the variation of these relationships with redshift and detect no evolution. We split SNe Ia into pairs of subsets that are based on the properties of the hosts and fit cosmological models to each subset. Including both systematic and statistical uncertainties, we do not find any significant shift in the best-fit cosmological parameters between the subsets. Among different SN Ia subsets, we find that SNe Ia in hosts with high specific star formation rates have the least intrinsic scatter ({sigma}_int_=0.08+/-0.01) in luminosity after standardization.
- ID:
- ivo://CDS.VizieR/J/ApJ/884/85
- Title:
- RELICS: Reionization Lensing Cluster Survey
- Short Name:
- J/ApJ/884/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Large surveys of galaxy clusters with the Hubble Space Telescope (HST) and Spitzer, including the Cluster Lensing And Supernova survey with Hubble and the Frontier Fields, have demonstrated the power of strong gravitational lensing to efficiently deliver large samples of high-redshift galaxies. We extend this strategy through a wider, shallower survey named RELICS, the Reionization Lensing Cluster Survey, described here. Our 188-orbit Hubble Treasury Program observed 41 clusters at 0.182<=z<=0.972 with Advanced Camera for Surveys (ACS) and WFC3/IR imaging spanning 0.4-1.7{mu}m. We selected 21 of the most massive clusters known based on Planck PSZ2 estimates and 20 additional clusters based on observed or inferred lensing strength. RELICS observed 46 WFC3/IR pointings (~200arcmin^2^) each with two orbits divided among four filters (F105W, F125W, F140W, and F160W) and ACS imaging as needed to achieve single-orbit depth in each of three filters (F435W, F606W, and F814W). As previously reported by Salmon+ (2020ApJ...889..189S), we discovered over 300 z~6-10 candidates, including the brightest z~6 candidates known, and the most distant spatially resolved lensed arc known at z~10. Spitzer IRAC imaging (945hr awarded, plus 100 archival, spanning 3.0-5.0{mu}m) has crucially enabled us to distinguish z~10 candidates from z~2 interlopers. For each cluster, two HST observing epochs were staggered by about a month, enabling us to discover 11 supernovae, including 3 lensed supernovae, which we followed up with 20 orbits from our program.
- ID:
- ivo://CDS.VizieR/J/ApJ/887/196
- Title:
- REQUIEM survey. I. Ly{alpha} halos around QSOs
- Short Name:
- J/ApJ/887/196
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The discovery of quasars a few hundred megayears after the Big Bang represents a major challenge to our understanding of black holes as well as galaxy formation and evolution. Quasars' luminosity is produced by extreme gas accretion onto black holes, which have already reached masses of M_BH_>10^9^M_{sun}_ by z~6. Simultaneously, their host galaxies form hundreds of stars per year, using up gas in the process. To understand which environments are able to sustain the rapid formation of these extreme sources, we started a Very Large Telescope/Multi-Unit Spectroscopic Explorer (MUSE) effort aimed at characterizing the surroundings of a sample of 5.7<z<6.6 quasars, which we have dubbed the Reionization Epoch QUasar InvEstigation with MUSE (REQUIEM) survey. We here present results of our searches for extended Ly{alpha} halos around the first 31 targets observed as part of this program. Reaching 5{sigma} surface brightness limits of 0.1-1.1x10^-17^erg/s/cm^2^/arcsec^2^ over a 1arcsec^2^ aperture, we were able to unveil the presence of 12 Ly{alpha} nebulae, eight of which are newly discovered. The detected nebulae show a variety of emission properties and morphologies with luminosities ranging from 8x10^42^ to 2x10^44^erg/s, FWHMs between 300 and 1700km/s, sizes <30pkpc, and redshifts consistent with those of the quasar host galaxies. As the first statistical and homogeneous investigation of the circumgalactic medium of massive galaxies at the end of the reionization epoch, the REQUIEM survey enables the study of the evolution of the cool gas surrounding quasars in the first 3Gyr of the universe. A comparison with the extended Ly{alpha} emission observed around bright (M_1450_<~-25mag) quasars at intermediate redshift indicates little variations on the properties of the cool gas from z~6 to z~3, followed by a decline in the average surface brightness down to z~2.
- ID:
- ivo://CDS.VizieR/J/ApJ/810/166
- Title:
- RESOLVE survey photometry catalog
- Short Name:
- J/ApJ/810/166
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present custom-processed ultraviolet, optical, and near-infrared photometry for the REsolved Spectroscopy of a Local VolumE (RESOLVE) survey, a volume-limited census of stellar, gas, and dynamical mass within two subvolumes of the nearby universe (RESOLVE-A and RESOLVE-B). RESOLVE is complete down to baryonic mass ~10^9.1-9.3^M_{sun}_, probing the upper end of the dwarf galaxy regime. In contrast to standard pipeline photometry (e.g., SDSS), our photometry uses optimal background subtraction, avoids suppressing color gradients, and employs multiple flux extrapolation routines to estimate systematic errors. With these improvements, we measure brighter magnitudes, larger radii, bluer colors, and a real increase in scatter around the red sequence. Combining stellar mass estimates based on our optimized photometry with the nearly complete HI mass census for RESOLVE-A, we create new z=0 volume-limited calibrations of the photometric gas fractions (PGF) technique, which predicts gas-to-stellar mass ratios (G/S) from galaxy colors and optional additional parameters. We analyze G/S-color residuals versus potential third parameters, finding that axial ratio is the best independent and physically meaningful third parameter. We define a "modified color" from planar fits to G/S as a function of both color and axial ratio. In the complete galaxy population, upper limits on G/S bias linear and planar fits. We therefore model the entire PGF probability density field, enabling iterative statistical modeling of upper limits and prediction of full G/S probability distributions for individual galaxies. These distributions have two-component structure in the red color regime. Finally, we use the RESOLVE-B 21cm census to test several PGF calibrations, finding that most systematically under- or overestimate gas masses, but the full probability density method performs well.
- ID:
- ivo://CDS.VizieR/J/A+A/437/789
- Title:
- Restframe I-band light curves of SN Ia
- Short Name:
- J/A+A/437/789
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a novel technique for fitting restframe I-band light curves on a data set of 42 type Ia supernovae (SNe Ia). Using the result of the fit, we construct a Hubble diagram with 26 SNe from the subset at 0.01<z<0.1. Adding two SNe at z~0.5 yields results consistent with a flat Lambda-dominated "concordance universe'' (Omega_M_,Omega_Lambda_)=(0.25, 0.75). For one of these, SN 2000fr, new near infrared data are presented. The high redshift supernova NIR data are also used to test for systematic effects in the use of SNe Ia as distance estimators. A flat, Lambda=0, universe where the faintness of supernovae at z~0.5 is due to grey dust homogeneously distributed in the intergalactic medium is disfavoured based on the high-z Hubble diagram using this small data-set. However, the uncertainties are large and no firm conclusion may be drawn. We explore the possibility of setting limits on intergalactic dust based on B-I and B-V colour measurements, and conclude that about 20 well measured SNe are needed to give statistically significant results. We also show that the high redshift restframe I-band data points are better fit by light curve templates that show a prominent second peak, suggesting that they are not intrinsically underluminous.
- ID:
- ivo://CDS.VizieR/J/ApJ/806/109
- Title:
- Rest-frame optical spectra of 3<z<6 QSOs
- Short Name:
- J/ApJ/806/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the rest-frame optical spectral properties of 155 luminous quasars at 3.3<z<6.4 taken with the AKARI space telescope, including the first detection of the H{alpha} emission line as far out as z~6. We extend the scaling relation between the rest-frame optical continuum and the line luminosity of active galactic nuclei (AGNs) to the high-luminosity, high-redshift regime that has rarely been probed before. Remarkably, we find that a single log-linear relation can be applied to the 5100{AA} and H{alpha} AGN luminosities over a wide range of luminosity (10^42^<L_5100_<10^47^ergs/s) or redshift (0<z<6), suggesting that the physical mechanism governing this relation is unchanged from z=0 to 6, over five decades in luminosity. Similar scaling relations are found between the optical and the UV continuum luminosities or line widths. Applying the scaling relations to the H{beta} black hole (BH) mass (M_BH_) estimator of local AGNs, we derive the M_BH_ estimators based on the H{alpha}, MgII, and CIV lines, finding that the UV-line-based masses are overall consistent with the Balmer-line-based, but with a large intrinsic scatter of 0.40dex for the CIV estimates. Our 43 M_BH_ estimates from H{alpha} confirm the existence of BHs as massive as ~10^10^M_{sun}_ out to z~5 and provide a secure footing for previous results from MgII-line-based studies that a rapid M_BH_ growth has occurred in the early universe.
- ID:
- ivo://CDS.VizieR/J/ApJ/755/60
- Title:
- Reverberation mapping for five Seyfert 1 galaxies
- Short Name:
- J/ApJ/755/60
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results from a detailed analysis of photometric and spectrophotometric data on five Seyfert 1 galaxies observed as a part of a recent reverberation mapping program. The data were collected at several observatories over a 140 day span beginning in 2010 August and ending in 2011 January. We obtained high sampling-rate light curves for Mrk 335, Mrk 1501, 3C 120, Mrk 6, and PG 2130+099, from which we have measured the time lag between variations in the 5100 {AA} continuum and the H{beta} broad emission line. We then used these measurements to calculate the mass of the supermassive black hole at the center of each of these galaxies. Our new measurements substantially improve previous measurements of M_BH_ and the size of the broad line-emitting region for four sources and add a measurement for one new object. Our new measurements are consistent with photoionization physics regulating the location of the broad line region in active galactic nuclei.