- ID:
- ivo://CDS.VizieR/J/MNRAS/425/1789
- Title:
- Berkeley supernova Ia program. I.
- Short Name:
- J/MNRAS/425/1789
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this first paper in a series, we present 1298 low-redshift (z<~0.2) optical spectra of 582 Type Ia supernovae (SNe Ia) observed from 1989 to 2008 as part of the Berkeley Supernova Ia Program (BSNIP). 584 spectra of 199 SNe Ia have well-calibrated light curves with measured distance moduli, and many of the spectra have been corrected for host-galaxy contamination. Most of the data were obtained using the Kast double spectrograph mounted on the Shane 3m telescope at Lick Observatory and have a typical wavelength range of 3300-10400{AA}, roughly twice as wide as spectra from most previously published data sets. We present our observing and reduction procedures, and we describe the resulting SN Database, which will be an online, public, searchable data base containing all of our fully reduced spectra and companion photometry. In addition, we discuss our spectral classification scheme (using the SuperNova IDentification code, SNID; Blondin & Tonry, 2007ApJ...666.1024B), utilizing our newly constructed set of SNID spectral templates.
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Search Results
- ID:
- ivo://CDS.VizieR/J/MNRAS/357/1267
- Title:
- b_j_ur photometry and redshifts of QSOs
- Short Name:
- J/MNRAS/357/1267
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The quasar sample selected by cross-correlating the Faint Images of the Radio Sky at Twenty cm (FIRST, <VIII/71>) survey and the 2-degree Field Quasar Redshift Survey (2QZ, <VII/223>) allows us to explore, for the first time, the faint end of the radio and optical luminosity functions up to z=~2.2. We find indications (~3{sigma}) of a negative evolution for these faint sources at z>~1.8, both in radio and optical bands. This corresponds to a decrement in the space density of faint quasars of approximately a factor 2 at z=2.2 and confirms the presence of a differential evolution for the population of radio-active quasars. The faint end of both luminosity functions flattens and the comparison with the (optical) number density of the whole quasar population supports a dependence of the fraction of radio-detected quasars on the optical luminosity. A progressive decrease in the fraction of quasars in the whole radio source population can be consistently accounted for within the receding torus scenario. The population of low-luminosity quasars, which the FIRST-2dF detects, appears to depart from the classical scheme for radio-loud quasars.
- ID:
- ivo://CDS.VizieR/J/PASJ/55/947
- Title:
- Blazars and Seyfert galaxies accretion rates
- Short Name:
- J/PASJ/55/947
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Accretion rates and their correlation with cosmological redshifts for a sample of blazars and Seyfert galaxies are presented. The sample includes 77 blazars (28 FSRQs, 26 LBLs, and 23 HBLs) and 60 Seyfert galaxies, of which the extended spectral energy distribution information and redshifts are available. Within the framework of accreting black holes, the accretion rates for these sources were estimated based on their bolometric luminosities.
- ID:
- ivo://CDS.VizieR/J/MNRAS/438/557
- Title:
- BLR-less AGNs in Stripe82
- Short Name:
- J/MNRAS/438/557
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is the first paper in a dedicated series to study the properties of the optically-selected broad-line-region-less (BLR-less) active galactic nuclei (AGNs; with no-hidden central broad emission line regions). We carried out a systematic search for the BLR-less AGNs through the Sloan Digital Sky Survey Legacy Survey (SDSS Stripe82 Database). Based on the spectral decomposition results for all the 136 676 spectroscopic objects (galaxies and quasars) with redshift less than 0.35 covered by the SDSS Stripe82 region, our spectroscopic sample for the BLR-less AGNs includes 22 693 pure narrow line objects without broad emission lines but with apparent AGN continuum emission R_AGN_>0.3 and apparent stellar lights R_ssp_>0.3. Then, using the properties of the photometry magnitude RMS (RMS) and Pearson's coefficients (R_1,2_) between two different SDSS band light curves: RMS_k_>3xRMS_Mk_ and R_1,2_>~0.8, the final 281 pure narrow line objects with true photometry variabilities are our selected reliable candidates for the BLR-less AGNs. The selected candidates with higher confidence levels not only have the expected spectral features of the BLR-less AGNs, but also show significant true photometry variabilities. The reported sample enlarges at least four times the current sample of the BLR-less AGNs, and will provide more reliable information to explain the lack of the BLRs of AGNs in our following studies.
- ID:
- ivo://CDS.VizieR/J/other/Ap/52.369
- Title:
- Blue stellar objects in strip DE=47{deg}
- Short Name:
- J/other/Ap/52.36
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This is a list of 111 blue stellar objects and individual active galaxies with excess ultraviolet continuum lying within 08h-17h in {alpha} and +45{deg} +49{deg} in {delta} (1950.0). The surveyed objects are classified in terms of activity type.
- 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.
- 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/MNRAS/204/151
- Title:
- Bright radio sources at 178 MHz (3CRR)
- Short Name:
- J/MNRAS/204/151
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A revised sample of bright radio sources at 178MHz is defined in order to correct the biases introduced into the 3CR catalog by confusion and partial resolution. The sample is shown to be 96 percent complete to a flux-density limit of 10Jy for sources smaller than 10arcmin. The bias of the 3CR catalog against objects of larger angular size is also reduced. Optical identifications are presented for 96 percent of the sources, 71 percent with galaxies and 25 percent with quasars. The radio-galaxy population is found to show strong space-density evolution for luminosities in excess of approximately 10^26.5^W/Hz/sr at 178MHz (redshifts greater than or approximately equal to 0.2), while the evolutionary properties of galaxies and quasars of the same luminosity and redshift are very similar.
- ID:
- ivo://CDS.VizieR/J/A+AS/118/65
- Title:
- BRI & redshifts in Cl0939+472 & Cl0016+161
- Short Name:
- J/A+AS/118/65
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a study of the galaxy population of Cl 0939+472 (z=0.41) and Cl 0016+161 (z=0.54). We have used narrow-band filters (FWHM=~90-200A) and broad band B, R, I filters covering the range from 3800A to 9200A obtain low resolution spectra for all galaxies brighter than R=22.5mag in a 5'x5' (Cl 0939+472) and a 3.5'x5' (Cl 0016+161) field. Template spectra for classical Hubble type and E+A galaxies were fitted to the low-resolution spectral energy distribution in order to determine the galaxies' redshift and the morphological type. We detected 160 cluster members in Cl 0939+472 and 100 in Cl 0016+161, with a success rate of about 80% in the determination of redshifts and corresponding classification of morphological types from spectral energy distributions. These results constitute a statistical improvement of at least a factor of 4 over the most complete study to date of these clusters. In particular, we provide a large sample of elliptical galaxies with secure membership, well suited for a study of evolutionary effects. The same E+A templates developed for the analysis of Cl 0939+472 were successful in recognizing almost all of the spectroscopically already known E+A galaxies in Cl 0016+161 and in identifying 10 new ones. Our results show that in this cluster, too, the fraction of E+A galaxies represents about 20% of the total galaxy population. This outlines the importance of taking into account galaxies with signs of recent star formation for a correct evaluation of the Butcher-Oemler effect in distant galaxy clusters.
- ID:
- ivo://CDS.VizieR/J/A+AS/124/283
- Title:
- BR magnitude and redshift of A1300
- Short Name:
- J/A+AS/124/283
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results of an optical follow-up of X-ray bright clusters of galaxies located between 0.15<=z<=0.31: B and R photometry as well as medium resolution spectroscopy of the galaxies. The cluster studied here - A1300 - is found to have a redshift of 0.3072 and a velocity dispersion of 1210km/s, based on 52 cluster members. Structures are observed in the galaxy number counts but the velocity histogram shows no significant departure from a Gaussian distribution.
