- ID:
- ivo://CDS.VizieR/J/AJ/150/153
- Title:
- Team Keck Redshift Survey 2 (TKRS2)
- Short Name:
- J/AJ/150/153
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Team Keck Redshift Survey 2 (TKRS2), a near-infrared spectral observing program targeting selected galaxies within the CANDELS subsection of the GOODS-North Field. The TKRS2 program exploits the unique capabilities of the Multi-Object Spectrometer For Infra-Red Exploration (MOSFIRE), which entered service on the Keck I telescope in 2012 and contributes substantially to the study of galaxy spectral features at redshifts inaccessible to optical spectrographs. The TKRS2 project targets 97 galaxies drawn from samples that include z~2 emission-line galaxies with features observable in the JHK bands as well as lower-redshift targets with features in the Y band. We present a detailed measurement of MOSFIRE's sensitivity as a function of wavelength, including the effects of telluric features across the YJHK filters. The largest utility of our survey is in providing rest-frame-optical emission lines for z>1 galaxies, and we demonstrate that the ratios of strong, optical emission lines of z~2 galaxies suggest the presence of either higher N/O abundances than are found in z~0 galaxies or low-metallicity gas ionized by an active galactic nucleus. We have released all TKRS2 data products into the public domain to allow researchers access to representative raw and reduced MOSFIRE spectra.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJ/626/L15
- Title:
- Templates for photometric redshifts of submm sources
- Short Name:
- J/ApJ/626/L15
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- There is growing evidence that some star-forming galaxies at z>1 are characterized by high efficiencies and specific star formation rates. In the local universe, these traits are shared by "active" blue compact dwarf galaxies (BCDs) with compact and dense star-forming regions. The spectral energy distributions (SEDs) of these BCDs are dominated by young massive star clusters, embedded in a cocoon of dust. In this Letter, we incorporate these BCD SEDs as templates for two samples of high-redshift galaxy populations selected at submillimeter wavelengths.
- ID:
- ivo://CDS.VizieR/J/ApJ/899/136
- Title:
- TESS light curve of AGN NGC 4395
- Short Name:
- J/ApJ/899/136
- Date:
- 03 Dec 2021 13:06:51
- Publisher:
- CDS
- Description:
- We present optical light curves from the Transiting Exoplanet Survey Satellite (TESS) for the archetypical dwarf active galactic nucleus (AGN) in the nearby galaxy NGC 4395 hosting a ~105M{sun} supermassive black hole (SMBH). Significant variability is detected on timescales from weeks to hours before reaching the background noise level. The ~month-long, 30 minute-cadence, high-precision TESS light curve can be well fit by a simple damped random walk (DRW) model, with the damping timescale {tau}DRW constrained to be 2.3_-0.7_^+1.8^days (1{sigma}). NGC 4395 lies almost exactly on the extrapolation of the {tau }_DRW_-M_BH_ relation measured for AGNs with BH masses that are more than three orders of magnitude larger. The optical variability periodogram can be well fit by a broken power law with the high-frequency slope (-1.88{+/-}0.15) and the characteristic timescale ({tau}_br_=1/(2{pi}f_br_)=1.4_-0.5_^+1.9^days) consistent with the DRW model within 1{sigma}. This work demonstrates the power of TESS light curves in identifying low-mass accreting SMBHs with optical variability, and a potential global {tau}_DRW}_-M_BH_ relation that can be used to estimate SMBH masses with optical variability measurements.
- ID:
- ivo://CDS.VizieR/J/A+A/608/A68
- Title:
- TeV/non-TeV BL Lacs multi-lambda fluxes
- Short Name:
- J/A+A/608/A68
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have collected the most complete multi-wavelength (6.0-6.0E^-18^cm) dataset of very high energy (VHE) gamma-ray emitting (TeV) BL Lacs, which are the most numerous extragalactic VHE sources. Using significant correlations between different bands, we aim to identify the best TeV BL Lac candidates that can be discovered by the current and next generation of imaging air Cherenkovtelescopes. We formed five datasets from lower energy data, i.e. radio, mid-infrared, optical, X-rays, and GeV gamma-ray, and five VHE gamma-ray datasets to perform a correlation study between different bands and to construct the prediction method. The low energy datasets were averaged for individual sources, while the VHE gamma-ray data were divided into subsets according to the flux state of the source. We then looked for significant correlations and determined their best-fit parameters. Using the best-fit parameters we predicted the level of VHE gamma-ray flux for a sample of 182 BL Lacs, which have not been detected at TeV energies. We identified the most promising TeV BL Lac candidates based on the predicted VHE gamma-ray flux for each source. We found 14 significant correlations between radio, mid-infrared, optical, gamma-ray, and VHE gamma-ray bands. The correlation between optical and VHE gamma-ray luminosity is established for the first time. We attribute this to the more complete sample and more accurate handling of host galaxy flux in our work. We found nine BL Lac candidates whose predicted VHE gamma-ray flux is high enough for detection in less than 25 hours with current imaging air Cherenkov telescopes.
- ID:
- ivo://CDS.VizieR/J/MNRAS/357/1231
- Title:
- Texas-Oxford NVSS (TONS) radio galaxies
- Short Name:
- J/MNRAS/357/1231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a clustering analysis of the Texas-Oxford NVSS Structure (TONS) radio galaxy redshift survey. This complete flux-limited survey consists of 268 radio galaxies with spectroscopic redshifts in three separate regions of the sky covering a total of 165{deg}^2^. By going to faint radio flux densities (S_1.4_>=3mJy) but imposing relatively bright optical limits (E~R~19.5), the TONS sample is optimized for looking at the clustering properties of low-luminosity radio galaxies in a region of moderate (0<=z<=0.5) redshifts. Description:
3646. The ACS-GC catalog
- ID:
- ivo://CDS.VizieR/J/ApJS/200/9
- Title:
- The ACS-GC catalog
- Short Name:
- J/ApJS/200/9
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the Advanced Camera for Surveys General Catalog (ACS-GC), a photometric and morphological database using publicly available data obtained with the Advanced Camera for Surveys (ACS) instrument on the Hubble Space Telescope. The goal of the ACS-GC database is to provide a large statistical sample of galaxies with reliable structural and distance measurements to probe the evolution of galaxies over a wide range of look-back times. The ACS-GC includes approximately 470000 astronomical sources (stars + galaxies) derived from the AEGIS, COSMOS, GEMS, and GOODS surveys. Galapagos code (Hausler et al. 2011ASPC..442..155H) was used to construct photometric (SExtractor) and morphological (Galfit) catalogs. The analysis assumes a single Sersic model for each object to derive quantitative structural parameters. We include publicly available redshifts from the DEEP2, COMBO-17, TKRS, PEARS, ACES, CFHTLS, and zCOSMOS surveys to supply redshifts (spectroscopic and photometric) for a considerable fraction (~74%) of the imaging sample. The ACS-GC includes color postage stamps, Galfit residual images, and photometry, structural parameters, and redshifts combined into a single catalog.
- ID:
- ivo://CDS.VizieR/J/AJ/156/191
- Title:
- The ages of M31 star clusters: SED versus CMD
- Short Name:
- J/AJ/156/191
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- It is well-known that fitting Color-Magnitude Diagrams (CMDs) to theoretical isochrones is the main method to determine star cluster ages. However, when CMDs are not available, the Spectral Energy Distribution (SED)-fitting technique is the only other approach, although it suffers the age-metallicity-reddening degeneracy. In this work, we gather the ages, metallicities, and masses of dozens of M31 star clusters from the CMD-fitting with Hubble Space Telescope images from the literature for comparison. We check the reliability of the SED-fitting results with different models, i.e., Bruzual & Charlot (2003MNRAS.344.1000B) model (BC03), Galaxy Evolutionary Synthesis Models (GALEV), and Advanced Stellar Population Synthesis (ASPS) for the simple stellar populations (SSPs) with single stars (ss)-SSP/binary-star (bs)-SSPs models. The photometry bands includes the Galaxy Evolution Explorer GALEX FUV/NUV bands, optical/near-infrared UBVRIJHK bands, as well as the Wide-field Infrared Survey Explorer (WISE) W1/W2 bands. The comparisons show that the SED-fitting ages agree well with the CMD-fitting ages, either with the fixed metallicity or with the free metallicity for both the BC03 and the GALEV model. However, for the ASPS models, it seems that SED-fitting results are systematically older than the CMD ages, especially for the ages log t<9.0 (year). The fitting also shows that the GALEX FUV/NUV-band are more important than the WISE W1/W2 for constraining the ages, which confirms the previous findings. We also derived the masses of our sample star clusters from the BC03 and GALEV models and it is found that the values agree well with those in the literature.
- ID:
- ivo://CDS.VizieR/J/MNRAS/485/1188
- Title:
- The ALMA Calibrator Catalogue
- Short Name:
- J/MNRAS/485/1188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a new catalogue of ALMA observations, the ALMA Calibrator Catalogue (ACC), collecting 3361 bright, compact radio sources, mostly blazars, used as calibrators. These sources were observed between 2011 May and 2018 July, for a total of 47115 pointings in different bands and epochs. A search in the online data bases yielded redshift measurements for 2245 sources.
- ID:
- ivo://CDS.VizieR/J/A+A/411/391
- Title:
- The AMIGA project. Revised positions for CIG galaxies
- Short Name:
- J/A+A/411/391
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present revised positions for the 1051 galaxies belonging to the Karachentseva Catalog of Isolated Galaxies (CIG, Cat. <VII/82>). New positions were calculated by applying SExtractor to the Digitized Sky Survey CIG fields with a spatial resolution of 1.2". We visually checked the results and for 118 galaxies had to recompute the assigned positions due to complex morphologies (e.g. distorted isophotes, undefined nuclei, knotty galaxies) or the presence of bright stars. We found differences between older and newer positions of up to 38" with a mean value of 2.96" relative to SIMBAD and up to 38" and 2.42" respectively relative to UZC (Cat. <J/PASP/111/438>). Based on star positions from the APM catalog (Cat. <I/267>) we determined that the DSS astrometry of five CIG fields has a mean offset in ({alpha},{delta}) of (-0.90", 0.93") with a dispersion of 0.4". These results have been confirmed using the 2MASS All-Sky Catalog of Point Sources (Cat. <II/246>). The intrinsic errors of our method combined with the astrometric ones are of the order of 0.5".
- ID:
- ivo://CDS.VizieR/J/MNRAS/278/1025
- Title:
- The APM Bright Galaxy Catalogue
- Short Name:
- J/MNRAS/278/1025
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The APM Bright Galaxy Catalogue lists positions, magnitudes, shapes and morphological types for 14,681 galaxies brighter than b(J) magnitude 16.44 over a 4,180 square degree area of the southern sky. Galaxy and stellar images have been located from glass copy plates of the United Kingdom Schmidt Telescope (UKST) IIIaJ sky survey using the Automated Photographic Measuring (APM) facility in Cambridge, England. The majority of stellar images are rejected by the regularity of their image surface brightness profiles. Remaining images are inspected by eye on film copies of the survey material and classed as stellar, multiple stellar, galaxy, merger or noise. Galaxies are further classified as elliptical, lenticular, spiral, irregular or uncertain. The 180 survey fields are put onto a uniform photometric system by comparing the magnitudes of galaxies in the overlap regions between neighbouring plates. The magnitude zero-point, photometric uniformity and photographic saturation are checked with CCD photometry. Finally, the completeness and reliability of the catalogue is assessed using various internal tests and by comparing with several independently constructed galaxy catalogues.
