- ID:
- ivo://CDS.VizieR/J/A+A/448/893
- Title:
- Photometry and lines of (z~0.2-1.0) galaxies
- Short Name:
- J/A+A/448/893
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the spectrophotometric properties of a sample of 141 emission-line galaxies at redshifts in the range 0.2<z<1.0 with a peak around 0.2<=z<=0.4. The analysis is based on medium resolution (Rs=500-600), optical spectra obtained at VLT and Keck. The targets are mostly "Canada-France Redshift Survey" (<VII/225>) emission-line galaxies, with the addition of field galaxies randomly selected behind lensing clusters. We complement this sample with galaxy spectra from the "Gemini Deep Deep Survey" (<J/AJ/127/2455>) public data release. We have computed absolute magnitudes of the galaxies and measured the line fluxes and equivalent widths of the main emission/absorption lines. The last two have been measured after careful subtraction of the fitted stellar continuum using the platefit software originally developed for the SDSS and adapted to our data. We present a careful comparison of this software with the results of manual measurements.
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Search Results
- ID:
- ivo://CDS.VizieR/J/AJ/159/17
- Title:
- Physical properties of SFRs in NGC 3395/NGC 3396
- Short Name:
- J/AJ/159/17
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report long-slit spectroscopy of the early major merger galaxies NGC 3395/NGC 3396. The spectra are consistent with those for star-forming galaxies, but there is some indication of LINER-like active galactic nucleus activity in the center of NGC 3396. The total star formation rate in the regions observed is 2.83 M_{sun}_/yr, consistent with estimates for the entire galaxies. The highest abundances are in the centers of the galaxies, with the abundances decreasing with distance. There is a correlation between high abundance and high ionization parameter, both of which can be attributed to the presence of massive stars. Modeling with SB 99 indicates the star-forming regions are younger than 10 Myr. There are 1000-2000 WNL stars in the system, along with several thousand O stars, consistent with the ages of the star-forming regions. The highest electron densities are found in young regions with high star formation rates. The electron temperatures are higher than results for non-interacting galaxies, which is probably due to shock waves produced by the galaxy-galaxy interaction, the outflow of gas from massive stars, and/or collisions between gas clouds in the galaxies. There is star formation in the bridge of material between the galaxies. These regions are among the youngest in the system and have low abundances, suggesting the gas was pulled from the outer parts of the galaxies. X-ray point sources, probably high-mass X-ray binaries, are associated with several star-forming regions.
- ID:
- ivo://CDS.VizieR/J/ApJ/852/81
- Title:
- 17 PS1 superluminous SNe LCs + classif. spectra
- Short Name:
- J/ApJ/852/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present light curves and classification spectra of 17 hydrogen-poor superluminous supernovae (SLSNe) from the Pan-STARRS1 Medium Deep Survey (PS1 MDS). Our sample contains all objects from the PS1 MDS sample with spectroscopic classification that are similar to either of the prototypes SN 2005ap or SN 2007bi, without an explicit limit on luminosity. With a redshift range 0.3<z<1.6, PS1 MDS is the first SLSN sample primarily probing the high-redshift population; our multifilter PS1 light curves probe the rest- frame UV emission, and hence the peak of the spectral energy distribution. We measure the temperature evolution and construct bolometric light curves, and find peak luminosities of (0.5-5)x10^44^erg/s and lower limits on the total radiated energies of (0.3-2)x10^51^erg. The light curve shapes are diverse, with both rise and decline times spanning a factor of ~5 and several examples of double-peaked light curves. When correcting for the flux-limited nature of our survey, we find a median peak luminosity at 4000{AA} of M_4000_=-21.1mag and a spread of {sigma}=0.7mag.
- ID:
- ivo://CDS.VizieR/J/ApJS/227/11
- Title:
- PS1 z>5.6 quasars follow-up
- Short Name:
- J/ApJS/227/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Luminous quasars at z>5.6 can be studied in detail with the current generation of telescopes and provide us with unique information on the first gigayear of the universe. Thus far, these studies have been statistically limited by the number of quasars known at these redshifts. Such quasars are rare, and therefore, wide-field surveys are required to identify them, and multiwavelength data are required to separate them efficiently from their main contaminants, the far more numerous cool dwarfs. In this paper, we update and extend the selection for the z~6 quasars presented in Banados+ (2014AJ....148...14B) using the Pan-STARRS1 (PS1) survey. We present the PS1 distant quasar sample, which currently consists of 124 quasars in the redshift range 5.6<~z<~6.7 that satisfy our selection criteria. Of these quasars, 77 have been discovered with PS1, and 63 of them are newly identified in this paper. We present the composite spectra of the PS1 distant quasar sample. This sample spans a factor of ~20 in luminosity and shows a variety of emission line properties. The number of quasars at z>5.6 presented in this work almost doubles the previously known quasars at these redshifts, marking a transition phase from studies of individual sources to statistical studies of the high-redshift quasar population, which was impossible with earlier, smaller samples.
- ID:
- ivo://CDS.VizieR/J/AJ/135/2470
- Title:
- Radio observations of the HDFS region. IV.
- Short Name:
- J/AJ/135/2470
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Australia Telescope Hubble Deep Field-South (ATHDF-S) survey of the Hubble Deep Field-South (HDF-S) reaches sensitivities of ~10uJy at 1.4, 2.5, 5.2, and 8.7GHz, making the ATHDF-S one of the deepest surveys ever performed with the Australia Telescope Compact Array (ATCA). Here, we present the optical identifications of the ATHDF-S radio sources using data from the literature. We find that ~66% of the radio sources have optical counterparts to I=23.5mag. Deep Hubble Space Telescope (HST) imaging of the area identifies a further 12% of radio sources. We present new spectroscopic observations for 98 of the radio sources and supplement these spectroscopic redshifts with photometric ones calculated from five-band optical imaging.
- ID:
- ivo://CDS.VizieR/J/ApJ/657/738
- Title:
- SDF galaxies multi-photometry
- Short Name:
- J/ApJ/657/738
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- SDF (Subaru Deep Field) line-emitting galaxies in four narrow-band filters at low and intermediate redshifts are presented. Broadband colors, follow-up optical spectroscopy, and multiple NB filters are used to distinguish H{alpha}, [OII], and [OIII] emitters at z=0.07-1.47 to construct their LFs. These LFs are derived down to faint magnitudes, allowing for an accurate determination of the faint-end slope. With a large (N~200) sample for each redshift interval, a Schechter profile is fitted to each LF.
- ID:
- ivo://CDS.VizieR/J/AJ/143/119
- Title:
- SDSS Quasar Lens Search. V. Final catalog
- Short Name:
- J/AJ/143/119
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final statistical sample of lensed quasars from the Sloan Digital Sky Survey (SDSS) Quasar Lens Search (SQLS). The well-defined statistical lens sample consists of 26 lensed quasars brighter than i=19.1 and in the redshift range of 0.6<z<2.2 selected from 50826 spectroscopically confirmed quasars in the SDSS Data Release 7 (DR7), where we restrict the image separation range to 1"<{theta}<20" and the i-band magnitude differences in two images to be smaller than 1.25mag. The SDSS-DR7 quasar catalog also contains 36 additional lenses identified with various techniques. In addition to these lensed quasars, we have identified 81 pairs of quasars from follow-up spectroscopy, 26 of which are physically associated binary quasars. The statistical lens sample covers a wide range of image separations, redshifts, and magnitudes, and therefore is suitable for systematic studies of cosmological parameters and surveys of the structure and evolution of galaxies and quasars.
- ID:
- ivo://CDS.VizieR/J/ApJ/887/38
- Title:
- SDSS RM Project: CIV lags & LCs from 4yrs of data
- Short Name:
- J/ApJ/887/38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present reverberation-mapping (RM) lags and black hole mass measurements using the CIV{lambda}1549 broad emission line from a sample of 348 quasars monitored as a part of the Sloan Digital Sky Survey RM Project. Our data span four years of spectroscopic and photometric monitoring for a total baseline of 1300 days, allowing us to measure lags up to ~750days in the observed frame (this corresponds to a rest-frame lag of ~300days in a quasar at z=1.5 and ~190days at z=3). We report significant time delays between the continuum and the CIV{lambda}1549 emission line in 48 quasars, with an estimated false-positive detection rate of 10%. Our analysis of marginal lag measurements indicates that there are on the order of ~100 additional lags that should be recoverable by adding more years of data from the program. We use our measurements to calculate black hole masses and fit an updated CIV radius-luminosity relationship. Our results significantly increase the sample of quasars with CIV RM results, with the quasars spanning two orders of magnitude in luminosity toward the high-luminosity end of the CIV radius-luminosity relation. In addition, these quasars are located at some of the highest redshifts (z~1.4-2.8) of quasars with black hole masses measured with RM.
- ID:
- ivo://CDS.VizieR/J/ApJ/825/126
- Title:
- SEAMBHs. V. The third year
- Short Name:
- J/ApJ/825/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- This paper reports results of the third-year campaign of monitoring super-Eddington accreting massive black holes (SEAMBHs) in active galactic nuclei (AGNs) between 2014 and 2015. Ten new targets were selected from the quasar sample of the Sloan Digital Sky Survey (SDSS), which have generally been more luminous than the SEAMBH candidates in the last two years. H{beta} lags ({tau}_H{beta}_) in five of the 10 quasars have been successfully measured in this monitoring season. We find that the lags are generally shorter, by large factors, than those of objects with same optical luminosity, in light of the well-known R_H{beta}_-L_5100_ relation. The five quasars have dimensionless accretion rates of dM/dt=10-10^3^. Combining these with measurements of the previous SEAMBHs, we find that the reduction of H{beta} lags depends tightly on accretion rates, {tau}_H{beta}_/{tau}_R-L_{propto}(dM/dt)^-0.42^, where {tau}_R-L_ is the H{beta} lag from the normal R_H{beta}_-L_5100_ relation. Fitting 63 mapped AGNs, we present a new scaling relation for the broad-line region: R_H{beta}_={alpha}_1_l_44_^{beta}1^min [1,(dM/dt)/(dM/dt)_c_)^-{gamma}1^], where l_44_=L_5100_/10^44^erg/s is the 5100{AA} continuum luminosity, and the coefficients are {alpha}_1_=29.6_-2.8_^+2.7^ lt-day, {beta}1=0.56_-0.03_^+0.03^, {gamma}1=0.52_-0.16_^+0.33^, and (dM/dt)_c_=11.19_-6.22_^+2.29^. This relation is applicable to AGNs over a wide range of accretion rates, from 10^-3^ to 10^3^. Implications of this new relation are briefly discussed.
- ID:
- ivo://CDS.VizieR/J/ApJS/219/8
- Title:
- SFR for WISE + SDSS spectroscopic galaxies
- Short Name:
- J/ApJS/219/8
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine Sloan Digitital Sky Survey (SDSS) and WISE photometry for the full SDSS spectroscopic galaxy sample, creating spectral energy distributions (SEDs) that cover {lambda}=0.4-22{mu}m for an unprecedentedly large and comprehensive sample of 858365 present-epoch galaxies. Using MAGPHYS (da Cunha+ 2008MNRAS.388.1595D), we then simultaneously and consistently model both the attenuated stellar SED and the dust emission at 12 and 22{mu}m, producing robust new calibrations for monochromatic mid-IR star formation rate (SFR) proxies. These modeling results provide the first mid-IR-based view of the bimodality in star formation activity among galaxies, exhibiting the sequence of star-forming galaxies ("main sequence") with a slope of dlogSFR/dlogM_*_=0.80 and a scatter of 0.39dex. We find that these new SFRs along the SF main sequence are systematically lower by a factor of 1.4 than those derived from optical spectroscopy. We show that for most present-day galaxies, the 0.4-22{mu}m SED fits can exquisitely predict the fluxes measured by Herschel at much longer wavelengths. Our analysis also illustrates that the majority of stars in the present-day universe are formed in luminous galaxies (~L*) in and around the "green valley" of the color-luminosity plane. We make publicly available the matched photometry catalog and SED modeling results.