- ID:
- ivo://CDS.VizieR/J/ApJS/98/477
- Title:
- Optical spectral atlas of Seyfert nuclei
- Short Name:
- J/ApJS/98/477
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical spectral atlas of the nuclear region (generally 2"x4", or r=<200pc) of a magnitude-limited survey of 486 nearby galaxies having B_T_=<12.5mag and {delta}>0deg. The double spectrograph on the Hale 5m telescope yielded simultaneous spectral coverage of ~4230-5110A and ~6210-6860A, with a spectral resolution of ~4A in the blue half and ~2.5A in the red half. This large, statistically significant survey contains uniformly observed and calibrated moderate-dispersion spectra of exceptionally high quality. The data presented in this paper will be used for various systematic studies of the physical properties of the nuclei of nearby galaxies, with special emphasis on searching for low-luminosity active galactic nuclei, or "dwarf" Seyferts. Our survey led to the discovery of four relatively obvious but previously uncataloged Seyfert galaxies (NGC 3735, 4395, 4639, and 6951), and many more galactic nuclei showing subtle evidence for Seyfert activity. We have also identified numerous low-ionization nuclear emission-line regions (LINERs), some of which may be powered by nonstellar processes. Of the many "starburst" nuclei in our sample, several exhibit the spectral features of Wolf-Rayet stars.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/680/939
- Title:
- Optical spectra of 24um galaxies in COSMOS. I.
- Short Name:
- J/ApJ/680/939
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study zCOSMOS-bright optical spectra for 609 Spitzer MIPS 24um-selected galaxies with S_24um_>0.30mJy and I<22.5 (AB mag) over 1.5deg^2^ of the COSMOS field.
- ID:
- ivo://CDS.VizieR/J/other/RMxAA/48.9
- Title:
- Optical spectroscopic atlas of MOJAVE AGNs
- Short Name:
- J/other/RMxAA/48
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical spectroscopic atlas for 123 core-dominated radio-loud active galactic nuclei with relativistic jets, drawn from the MOJAVE/2cm (Monitoring of Jets in AGN with VLBA Experiments) sample at 15GHz. It is the first time that spectroscopic and photometric parameters for a large sample of such type of AGN are presented.
- ID:
- ivo://CDS.VizieR/J/AJ/109/14
- Title:
- Optical spectroscopy of Abell clusters. I.
- Short Name:
- J/AJ/109/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present results of a program of optical spectroscopy of radio galaxies in rich clusters. Redshifts are reported for 268 radio galaxies or close companions in Abell clusters and 36 objects which turned out to be foreground or background objects. Absolute line strengths are also reported for the 3727{AA} [OII] line and the [NII]/H{alpha} complex. We find no evidence that the radio activity in our sample of mostly FR I radio galaxies is associated with emission-line luminosities above those found in "normal" galaxies of the same absolute magnitude and optical type. We also find that the radial velocity differences between radio galaxies and the cluster mean seem mainly to be a function of galaxy absolute magnitude rather than radio properties.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/124
- Title:
- Optical spectroscopy of ECDF-S X-ray sources
- Short Name:
- J/ApJS/191/124
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a program to acquire high-quality optical spectra of X-ray sources detected in the Extended-Chandra Deep Field-South (E-CDF-S) and its central 2Ms area. New spectroscopic redshifts, up to z=4, are measured for 283 counterparts to Chandra sources with deep exposures (t~2-9hr per pointing) using multi-slit facilities on both VLT (VIMOS) and Keck (DEIMOS), thus bringing the total number of spectroscopically identified X-ray sources to over 500 in this survey field. Since our new spectroscopic identifications are mainly associated with X-ray sources in the shallower 250ks coverage, we provide a comprehensive catalog of X-ray sources detected in the E-CDF-S including the optical and near-infrared counterparts, determined by a likelihood routine, and redshifts (both spectroscopic and photometric), that incorporate published spectroscopic catalogs, thus resulting in a final sample with a high fraction (80%) of X-ray sources having secure identifications. Our redshift catalog includes 17 type-2 QSOs at 1<~z<~3.5. Based on our deepest (9 hr) VLT/VIMOS observation, we identify "elusive" optically faint galaxies (Rmag~25) at z~2-3 based upon the detection of interstellar absorption lines (e.g., OII+SiIV, CII], CIV).
- ID:
- ivo://CDS.VizieR/J/AJ/133/186
- Title:
- Optical spectroscopy of 77 luminous AGNs and QSOs
- Short Name:
- J/AJ/133/186
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present optical spectroscopy of a sample of 77 luminous active galactic nuclei (AGNs) and quasars selected on the basis of their mid-infrared colors. Our objects are selected from the Spitzer Extragalactic First Look Survey and the SWIRE XMM-Newton Large-Scale Structure Survey (XMM-LSS) fields, with a typical 24um flux density of 5mJy. The median redshift is 0.6, with a range of ~0.05-4. Only 33% (25 out of 77) of these objects are normal type 1 quasars, with no obscuration. Forty-four percent (34 out of 77) are type 2 objects, with high-ionization, narrow emission lines, and 14% (11 out of 77) are dust-reddened type 1 quasars, showing broad lines but a dust-reddened or unusually weak quasar continuum.
- ID:
- ivo://CDS.VizieR/J/A+A/561/A89
- Title:
- Optical spectroscopy of 24 Ly-alpha emitters
- Short Name:
- J/A+A/561/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Among the different observational techniques used to select high-redshift galaxies, the hydrogen recombination line Lyman-alpha (Ly{alpha}) is of particular interest because it gives access to the measurement of cosmological quantities such as the star formation rate (SFR) of distant galaxy populations. However, interpreting this line and calibrating such observables are still subject to serious uncertainties. In this context, it important to understand the mechanisms responsible for the attenuation of Ly{alpha} emission, and under what conditions the Ly{alpha} emission line can be used as a reliable star formation diagnostic tool. We used a sample of 24 Ly{alpha} emitters at z~0.3 with an optical spectroscopic follow-up to calculate the Ly{alpha} escape fraction and its dependence upon different physical properties. We also examined the reliability of Ly{alpha} as a SFR indicator. We combined these observations with a compilation of Ly{alpha} emitters selected at z=0-0.3 from the literature to assemble a larger sample.
- ID:
- ivo://CDS.VizieR/J/ApJ/663/218
- Title:
- Optical Spectroscopy of WIYN Hydra FLS sources
- Short Name:
- J/ApJ/663/218
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an optical spectroscopic survey of 24um and 1.4GHz sources, detected in the Spitzer extragalactic First Look Survey (FLS), using the multifiber spectrograph, Hydra, on the WIYN telescope. We have obtained spectra for 772 sources, with flux densities above 0.15mJy in the infrared and 0.09mJy in the radio. The redshifts measured in this survey are mostly in the range 0<z<0.4, with a distribution peaking at z~0.2.
- ID:
- ivo://CDS.VizieR/J/ApJ/895/49
- Title:
- Optical spectrum of ZTF18abvkwla and its host galaxy
- Short Name:
- J/ApJ/895/49
- Date:
- 16 Mar 2022 00:26:26
- Publisher:
- CDS
- Description:
- We present ZTF18abvkwla (the "Koala"), a fast blue optical transient discovered in the Zwicky Transient Facility (ZTF) One-Day Cadence (1DC) Survey. ZTF18abvkwla has a number of features in common with the groundbreaking transient AT2018cow: blue colors at peak (g-r~-0.5mag), a short rise time from half-max of under two days, a decay time to half-max of only three days, a high optical luminosity (M_g.peak_~-20.6mag), a hot (>~40000K) featureless spectrum at peak light, and a luminous radio counterpart. At late times ({Delta}>80days), the radio luminosity of ZTF18abvkwla ({nu}L_{nu}_>~10^40^erg/s at 10GHz, observer-frame) is most similar to that of long-duration gamma-ray bursts (GRBs). The host galaxy is a dwarf starburst galaxy (M~5x10^8^M{odot}, SFR~7M{odot}/yr) that is moderately metal-enriched (log[O/H]~8.5), similar to the hosts of GRBs and superluminous supernovae. As in AT2018cow, the radio and optical emission in ZTF18abvkwla likely arise from two separate components: the radio from fast- moving ejecta ({Gamma}{beta}c>0.38c) and the optical from shock-interaction with confined dense material (<0.07M{sun} in ~10^15^cm). Compiling transients in the literature with t_rise_<5days and M_peak_<-20mag, we find that a significant number are engine-powered, and suggest that the high peak optical luminosity is directly related to the presence of this engine. From 18 months of the 1DC survey, we find that transients in this rise-luminosity phase space are at least two to three orders of magnitude less common than CC SNe. Finally, we discuss strategies for identifying such events with future facilities like the Large Synoptic Survey Telescope, as well as prospects for detecting accompanying X-ray and radio emission.
- ID:
- ivo://CDS.VizieR/J/MNRAS/446/943
- Title:
- Optical supernova remnants in nearby galaxies
- Short Name:
- J/MNRAS/446/943
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper, we present the most up-to-date list of nearby galaxies with optically detected supernova remnants (SNRs). We discuss the contribution of the H{alpha} flux from the SNRs to the total H{alpha} flux and its influence on the derived star formation rate (SFR) for 18 galaxies in our sample. We found that the contribution of SNR flux to the total H{alpha} flux is 5+/-5%. Due to the observational selection effects, the SNR contamination of SFRs derived herein represents only a lower limit.
