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851. Flux calibrations and WZ Oph photometry
ID:
ivo://CDS.VizieR/J/ApJ/723/1469
Title:
Flux calibrations and WZ Oph photometry
Short Name:
J/ApJ/723/1469
Date:
21 Oct 2021
Publisher:
CDS
Description:
Among several EB distance algorithms, direct comparison of observed and theoretical fluxes is particularly straightforward, although it requires absolute flux calibrations for which only a modest number of publications exist. Here, we measure UBV RI and uvby flux calibrations and calibration ratios from astronomical objects in ways not previously tried, specifically for EBs, single stars within 80pc, and the Sun. All of the single stars are below about 6500K temperature. Interstellar extinction is avoided by a restriction to nearby targets. Some photometric band calibrations in the literature are accurate enough for very good EB distance determinations if star temperatures are accurately known, especially considering that estimated distance has only a square-root dependence on calibration constant, but accurate band-to-band calibration ratios are keys to the combined temperature-distance problem. Band-independent canceling factors (star radii and distances) allow calibration ratio measurement with enhanced accuracy, compared to individual band calibrations. A physical EB model with embedded stellar atmosphere emission optimally matches theory to observations for the binaries. Single star candidates are identified as reliably single if their radial velocity variations are below 100m/s. For the most part, we find good agreement with some of the previous calibrations and the ratios are improved.
852. Fluxes in nearby star-forming galaxies
ID:
ivo://CDS.VizieR/J/ApJ/706/553
Title:
Fluxes in nearby star-forming galaxies
Short Name:
J/ApJ/706/553
Date:
21 Oct 2021
Publisher:
CDS
Description:
Compared to starburst galaxies, normal star-forming galaxies have been shown to display a much larger dispersion of the dust attenuation at fixed reddening through studies of the IRX-{beta} diagram (the IR/UV ratio "IRX" versus the UV color "{beta}"). To investigate the causes of this larger dispersion and attempt to isolate second parameters, we have used GALEX UV, ground-based optical, and Spitzer infrared imaging of eight nearby galaxies, and examined the properties of individual UV and 24um selected star-forming regions. We concentrated on star-forming regions, in order to isolate simpler star formation histories than those that characterize whole galaxies.
853. Fluxes of NGG7793 & NGC4945 with GMOS-S
ID:
ivo://CDS.VizieR/J/ApJ/812/39
Title:
Fluxes of NGG7793 & NGC4945 with GMOS-S
Short Name:
J/ApJ/812/39
Date:
21 Oct 2021
Publisher:
CDS
Description:
Gas-phase abundances in HII regions of two spiral galaxies, NGC7793 and NGC4945, have been studied to determine their radial metallicity gradients. We used the strong-line method to derive oxygen abundances from spectra acquired with GMOS-S, the multi-object spectrograph on the 8m Gemini South telescope. We found that NGC7793 has a well-defined gas-phase radial oxygen gradient of -0.321+/-0.112dexR_25_^-1^ (or -0.054+/-0.019dex/kpc) in the galactocentric range 0.17<R_G_/R_25_<0.82, not dissimilar from gradients calculated with direct abundance methods in galaxies of similar mass and morphology. We also determined a shallow radial oxygen gradient in NGC 4945, -0.253+/-0.149dexR_25_^-1^ (or -0.019+/-0.011dex/kpc) for 0.04<R_G_/R_25_<0.51, where the larger relative uncertainty derives mostly from the larger inclination of this galaxy. NGC 7793 and NGC 4945 have been selected for this study because they are similar, in mass and morphology, to M33 and the Milky Way, respectively. Since at zeroth order we expect the radial metallicity gradients to depend on mass and galaxy type, we compared our galaxies in the framework of radial metallicity models best suited for M33 and the Galaxy. We found a good agreement between M33 and NGC7793, pointing toward similar evolution for the two galaxies. We notice instead differences between NGC 4945 and the radial metallicity gradient model that best fits the Milky Way. We found that these differences are likely related to the presence of an active galactic nucleus combined with a bar in the central regions of NGC 4945, and to its interacting environment.
854. FOCAT-S Catalogue
ID:
ivo://CDS.VizieR/I/195
Title:
FOCAT-S Catalogue
Short Name:
I/195
Date:
21 Oct 2021
Publisher:
CDS
Description:
This is a new reduction of FOCAT-S photographic catalogue of southern stars. This reduction has to replace the preceding one. The differences from previous version are as follows: 1. The new version was sorted according right ascension of stars inside 10-degree declination zone; 2. New proper motions were calculated for all almost stars. New Astrographic Catalogue plate reduction was developed for this aim. The average rms of new FOCAT-S proper motions is 0.002 - 0.003 "/year; 3. The number of the Astrographic Catalogue star positions used for the proper motion calculation is added; 4. The magnitude (mag) and spectral type (Sp) columns were revised significantly: some errors were corrected; stars identified in C.S.I. catalogue have got Mag, Sp from this catalogue as it was in previous version. Other stars have got Mag, Sp from PPM-S catalogue. 5. The list of Durchmusterung star numbers was changed. Now it contains the Cape Photographic Durchmusterung (CPD) numbers for stars in [-90, -23] declination zones; Cordoba Durchmusterung (CoD) star numbers are used only if it was impossible to identify star in BD or CPD. Format of this column was changed also. 6. PPM catalogue star numbers were added.
855. Follow-up of candidate counterparts of S190814bv
ID:
ivo://CDS.VizieR/J/ApJ/890/131
Title:
Follow-up of candidate counterparts of S190814bv
Short Name:
J/ApJ/890/131
Date:
21 Oct 2021
Publisher:
CDS
Description:
On 2019 August 14, the Advanced LIGO and Virgo interferometers detected the high-significance gravitational wave (GW) signal S190814bv. The GW data indicated that the event resulted from a neutron star-black hole (NSBH) merger, or potentially a low-mass binary BH merger. Due to the low false-alarm rate and the precise localization (23deg^2^ at 90%), S190814bv presented the community with the best opportunity yet to directly observe an optical/near-infrared counterpart to an NSBH merger. To search for potential counterparts, the GROWTH Collaboration performed real-time image subtraction on six nights of public Dark Energy Camera images acquired in the 3 weeks following the merger, covering >98% of the localization probability. Using a worldwide network of follow-up facilities, we systematically undertook spectroscopy and imaging of optical counterpart candidates. Combining these data with a photometric redshift catalog, we ruled out each candidate as the counterpart to S190814bv and placed deep, uniform limits on the optical emission associated with S190814bv. For the nearest consistent GW distance, radiative transfer simulations of NSBH mergers constrain the ejecta mass of S190814bv to be M_ej_<0.04M_{sun}_ at polar viewing angles, or M_ej_<0.03M_{sun}_ if the opacity is {kappa}<2cm^2^g^-1^. Assuming a tidal deformability for the NS at the high end of the range compatible with GW170817 results, our limits would constrain the BH spin component aligned with the orbital momentum to be {chi}<0.7 for mass ratios Q<6, with weaker constraints for more compact NSs.
856. Follow-up spectroscopy of SDSS changing-look QSOs
ID:
ivo://CDS.VizieR/J/ApJ/874/8
Title:
Follow-up spectroscopy of SDSS changing-look QSOs
Short Name:
J/ApJ/874/8
Date:
21 Oct 2021
Publisher:
CDS
Description:
Active galactic nuclei (AGNs) that show strong rest-frame optical/UV variability in their blue continuum and broad line emission are classified as changing-look AGN, or at higher luminosities, changing-look quasars (CLQs). These surprisingly large and sometimes rapid transitions challenge accepted models of quasar physics and duty cycles, offer several new avenues for study of quasar host galaxies, and open a wider interpretation of the cause of differences between broad and narrow-line AGN. To better characterize extreme quasar variability, we present follow-up spectroscopy as part of a comprehensive search for CLQs across the full Sloan Digital Sky Survey (SDSS) footprint using spectroscopically confirmed quasars from the SDSS DR7 catalog. Our primary selection requires large-amplitude (|{Delta}g|>1mag, |{Delta}r|>0.5mag) variability over any of the available time baselines probed by the SDSS and Pan-STARRS 1 surveys. We employ photometry from the Catalina Sky Survey to verify variability behavior in CLQ candidates where available, and confirm CLQs using optical spectroscopy from the William Herschel, MMT, Magellan, and Palomar telescopes. For our adopted signal-to-noise ratio threshold on variability of broad H{beta} emission, we find 17 new CLQs, yielding a confirmation rate of >~20%. These candidates are at lower Eddington ratio relative to the overall quasar population, which supports a disk-wind model for the broad line region. Based on our sample, the CLQ fraction increases from 10% to roughly half as the continuum flux ratio between repeat spectra at 3420{AA} increases from 1.5 to 6. We release a catalog of more than 200 highly variable candidates to facilitate future CLQ searches.
857. FON Astrographic Catalogue Southern Part (FONAC-S)
ID:
ivo://CDS.VizieR/I/346
Title:
FON Astrographic Catalogue Southern Part (FONAC-S)
Short Name:
I/346
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalog of positions and B-magnitudes of stars and galaxies of the southern sky (from -20{deg} to +2{deg}) was created as a part of the FON (Russian abbreviation Photographic Sky Survey) project at the Ulugh Beg Astronomical Institute (UBAI) of the Uzbekistan Academy of Sciences. The data accumulated in the Photographic Archive of the UBAI were used. The total number of processed plates is 1963. Astronegatives were digitized with Epson Expression 10000XL scanners in the 1200 dpi scanning mode. The majority of plates have a size of 30x30cm. The catalog contains the data on 13 413 268 stars and galaxies with B<=17.5m at the epoch of 1984.97. The coordinates of stars and galaxies were obtained in the Tycho-2 reference system, and B-magnitudes were determined in the system of photoelectric standards. The mean internal errors of the catalog are {sigma}_RA,DE_=0.23" and {sigma}_B_=0.15mag for all objects or {sigma}_RA,DE_=0.085" and {sigma}_B_=0.054mag for the objects in the B=7-14mag range. The convergence between the catalog and Tycho-2 is characterized by the following values: 0.042" and 0.16m. The mean-square difference in coordinates from the catalog and from UCAC-4 is {sigma}_RA,DE_=0.26" (9 892 697 objects, or 73.75% of stars and galaxies, were identified).
858. FON Astrographic Catalogue, Version 3.0
ID:
ivo://CDS.VizieR/I/342
Title:
FON Astrographic Catalogue, Version 3.0
Short Name:
I/342
Date:
05 Nov 2021
Publisher:
CDS
Description:
The catalog of equatorial coordinates {alpha} and {delta} and B-magnitudes of stars of the northern sky (from -4{deg} to +90{deg}) was created as a part of the FON project at the Main Astronomical Observatory of the National Academy of Sciences of Ukraine. The data accumulated in the Joint Digital Archive of the Ukrainian Virtual Observatory were used. The total number of processed plates is 2260. Astronegatives were digitized with Microtek ScanMaker 9800XL TMA and Epson Expression 10000XL scanners in the 1200 dpi scanning mode. The majority of plates have a size of 30x30cm (13000x13000-pixels). The catalog contains the data on 19451751 stars and galaxies with B<=16.5m at the epoch of 1988.1. The coordinates of stars and galaxies were obtained in the Tycho-2 reference system, and B-magnitudes were determined in the system of photoelectric standards. The mean internal errors of the catalog are {simag}_RA,DE_=0.23" and {sigma}_B_=0.14mag for all objects or {simag}_RA,DE_=0.10" and {sigma}_B_=0.07mag for stars in the B=7-14mag range. The convergence between the catalog and Tycho-2 is characterized by the following values: 0.06" and 0.15m. The mean-square difference in coordinates from the catalog and from UCAC-4 is {simag}_RA,DE_= 0.30" (18 742 932 objects, or 96.36% of stars and galaxies, were cross-identified).
859. Foreground galaxies toward FRB 190608 from SDSS
ID:
ivo://CDS.VizieR/J/ApJ/901/134
Title:
Foreground galaxies toward FRB 190608 from SDSS
Short Name:
J/ApJ/901/134
Date:
21 Feb 2022 09:50:38
Publisher:
CDS
Description:
Fast radio burst (FRB) 190608 was detected by the Australian Square Kilometre Array Pathfinder (ASKAP) and localized to a spiral galaxy at z_host_=0.11778 in the Sloan Digital Sky Survey (SDSS) footprint. The burst has a large dispersion measure (DM_FRB_=339.8pc/cm^3^) compared to the expected cosmic average at its redshift. It also has a large rotation measure (RM_FRB_=353rad/m^2^) and scattering timescale ({tau}=3.3ms at 1.28GHz). Chittidi+ (2021ApJ...922..173C) perform a detailed analysis of the ultraviolet and optical emission of the host galaxy and estimate the host DM contribution to be 110+/-37pc/cm^3^. This work complements theirs and reports the analysis of the optical data of galaxies in the foreground of FRB 190608 in order to explore their contributions to the FRB signal. Together, the two studies delineate an observationally driven, end-to-end study of matter distribution along an FRB sightline, the first study of its kind. Combining our Keck Cosmic Web Imager (KCWI) observations and public SDSS data, we estimate the expected cosmic dispersion measure DM_cosmic along the sightline to FRB 190608. We first estimate the contribution of hot, ionized gas in intervening virialized halos (DM_halos_~7-28pc/cm^3^). Then, using the Monte Carlo Physarum Machine methodology, we produce a 3D map of ionized gas in cosmic web filaments and compute the DM contribution from matter outside halos (DM_IGM_~91-126pc/cm^3^). This implies that a greater fraction of ionized gas along this sightline is extant outside virialized halos. We also investigate whether the intervening halos can account for the large FRB rotation measure and pulse width and conclude that it is implausible. Both the pulse broadening and the large Faraday rotation likely arise from the progenitor environment or the host galaxy.
860. Fornax Deep Survey with VST. V. Isophote fit
ID:
ivo://CDS.VizieR/J/A+A/623/A1
Title:
Fornax Deep Survey with VST. V. Isophote fit
Short Name:
J/A+A/623/A1
Date:
21 Oct 2021
Publisher:
CDS
Description:
This paper is based on the multi-band (ugri) Fornax Deep Survey (FDS) with the VLT Survey Telescope (VST). We study bright early-type galaxies (m_B_<15mag) in the 9 square degrees around the core of the Fornax cluster, which covers the virial radius (R_vir~0.7Mpc). The main goal of the present work is to provide an analysis of the light distribution for all galaxies out to unprecedented limits (in radius and surface brightness) and to release the main products resulting from this analysis in all FDS bands. We give an initial comprehensive view of the galaxy structure and evolution as a function of the cluster environment. From the isophote fit, we derived the azimuthally averaged surface brightness profiles, the position angle, and ellipticity profiles as a function of the semi-major axis. In each band, we derived the total magnitudes, effective radii, integrated colours, and stellar mass-to-light ratios. The long integration times, the arcsec-level angular resolution of OmegaCam@VST, and the large covered area of FDS allow us to map the light and colour distributions out to large galactocentric distances (up to about 10^-15^Re) and surface brightness levels beyond mu_r_=27mag/arcsec^2^ (mu_B_>28mag/arcsec^2^). Therefore, the new FDS data allow us to explore in great detail the morphology and structure of cluster galaxies out to the region of the stellar halo. The analysis presented in this paper allows us to study how the structure of galaxies and the stellar population content vary with the distance from the cluster centre. In addition to the intra-cluster features detected in previous FDS works, we found a new faint filament between FCC 143 and FCC 147, suggesting an ongoing interaction. The observations suggest that the Fornax cluster is not completely relaxed inside the virial radius. The bulk of the gravitational interactions between galaxies happens in the W-NW core region of the cluster, where most of the bright early-type galaxies are located and where the intra-cluster baryons (diffuse light and globular clusters) are found. We suggest that the W-NW sub-clump of galaxies results from an infalling group onto the cluster, which has modified the structure of the galaxy outskirts (making asymmetric stellar halos) and has produced the intra-cluster baryons (ICL and GCs), concentrated in this region of the cluster.