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2751. Phoenix Deep Survey spectroscopic catalog
ID:
ivo://CDS.VizieR/J/ApJ/624/135
Title:
Phoenix Deep Survey spectroscopic catalog
Short Name:
J/ApJ/624/135
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Phoenix Deep Survey is a multiwavelength survey based on deep 1.4GHz radio imaging, reaching well into the sub-100uJy level. One of the aims of this survey is to characterize the submillijansky radio population, exploring its nature and evolution. In this paper we present the catalog and results of the spectroscopic observations aimed at characterizing the optically "bright" (R<~21.5mag) counterparts of faint radio sources. Of 371 sources with redshift determination, 21% have absorption lines only, 11% show active galactic nucleus signatures, 32% are star-forming galaxies, 34% show narrow emission lines that do not allow detailed spectral classification (owing to poor signal-to-noise ratio and/or lack of diagnostic emission lines), and the remaining 2% are identified with stars.
2752. Phoenix dwarf galaxy RV and [Fe/H] catalog
ID:
ivo://CDS.VizieR/J/MNRAS/466/2006
Title:
Phoenix dwarf galaxy RV and [Fe/H] catalog
Short Name:
J/MNRAS/466/2006
Date:
21 Oct 2021
Publisher:
CDS
Description:
Transition type dwarf galaxies are thought to be systems undergoing the process of transformation from a star-forming into a passively evolving dwarf, which makes them particularly suitable to study evolutionary processes driving the existence of different dwarf morphological types. Here we present results from a spectroscopic survey of ~200 individual red giant branch stars in the Phoenix dwarf, the closest transition type with a comparable luminosity to 'classical' dwarf galaxies. We measure a systemic heliocentric velocity Vhelio=-21.2+/-1.0km/s. Our survey reveals the clear presence of prolate rotation that is aligned with the peculiar spatial distribution of the youngest stars in Phoenix. We speculate that both features might have arisen from the same event, possibly an accretion of a smaller system. The evolved stellar population of Phoenix is relatively metal-poor (<[Fe/H]>=-1.49+/-0.04dex) and shows a large metallicity spread (sigma_[Fe/H]_=0.51+/-0.04dex), with a pronounced metallicity gradient of -0.13+/-0.01dex/arcmin similar to luminous, passive dwarf galaxies. We also report a discovery of an extremely metal-poor star candidate in Phoenix and discuss the importance of correcting for spatial sampling when interpreting the chemical properties of galaxies with metallicity gradients. This study presents a major leap forward in our knowledge of the internal kinematics of the Phoenix transition type dwarf galaxy and the first wide area spectroscopic survey of its metallicity properties.
2753. Photodissociation regions in M33
ID:
ivo://CDS.VizieR/J/MNRAS/416/2
Title:
Photodissociation regions in M33
Short Name:
J/MNRAS/416/2
Date:
21 Oct 2021
Publisher:
CDS
Description:
We derive total (atomic + molecular) hydrogen densities in giant molecular clouds (GMCs) in the nearby spiral galaxy M33 using a method that views the atomic hydrogen near regions of recent star formation as the product of photodissociation. Far-ultraviolet (FUV) photons emanating from a nearby OB association produce a layer of atomic hydrogen on the surfaces of nearby GMCs. Our approach provides an estimate of the total hydrogen density in these GMCs from observations of the excess FUV emission that reaches the GMC from the OB association and of the excess 21-cm radio HI emission produced after these FUV photons convert H2 into HI on the GMC surface. The method provides an alternative approach to the use of CO emission as a tracer of H2 in GMCs and is especially sensitive to a range of densities well below the critical density for CO(1-0) emission.
2754. Photodissociation with mechanical heating
ID:
ivo://CDS.VizieR/J/A+A/574/A127
Title:
Photodissociation with mechanical heating
Short Name:
J/A+A/574/A127
Date:
21 Oct 2021
Publisher:
CDS
Description:
CO observations in active galactic nuclei and starbursts reveal high kinetic temperatures. Those environments are thought to be very turbulent due to dynamic phenomena, such as outflows and high supernova rates. We investigate the effect of mechanical heating on atomic fine-structure and molecular lines and on their ratios. We try to use those ratios as a diagnostic to constrain the amount of mechanical heating in an object and also study its significance on estimating the H_2_ mass. Equilibrium photodissociation models (PDRs hereafter) were used to compute the thermal and chemical balance for the clouds. The equilibria were solved for numerically using the optimized version of the Leiden PDR-XDR code. Large velocity-gradient calculations were done as post-processing on the output of the PDR models using RADEX. High-J CO line ratios are very sensitive to mechanical heating ({GAMMA}mech hereafter). Emission becomes at least one order of magnitude brighter in clouds with n~10^5^cm^-3^ and a star formation rate of 1M_{sun}/yr (corresponding to {GAMMA}mech=2x10^-19^erg/cm^3^/s). The Emission of low-J CO lines is not as sensitive to {GAMMA}mech, but they do become brighter in response to {GAMMA}mech. Generally, for all of the lines we considered, {GAMMA}mech increases excitation temperatures and decreases the optical depth at the line centre. Hence line ratios are also effected, strongly in some cases. Ratios involving HCN are a good diagnostic for {GAMMA}mech , where the HCN(1-0)/CO(1-0) increases from 0.06 to 0.25, and the HCN(1-0)/HCO^+^ (1-0) increase from 0.15 to 0.5 for amounts of {GAMMA}mech that are equivalent to 5% of the surface heating rate. Both ratios increase to more than 1 for higher {GAMMA}mech , as opposed to being much less than unity in pure PDRs. The first major conclusion is that low-J to high-J intensity ratios will yield a good estimate of the mechanical heating rate (as opposed to only low-J ratios). The second one is that the mechanical heating rate should be taken into account when determining AV or, equivalently, NH, and consequently the cloud mass. Ignoring {GAMMA}mech will also lead to large errors in density and radiation field estimates.
2755. Photoelectric types of bright galaxies
ID:
ivo://CDS.VizieR/J/AJ/109/517
Title:
Photoelectric types of bright galaxies
Short Name:
J/AJ/109/517
Date:
21 Oct 2021
Publisher:
CDS
Description:
The photoelectric total magnitudes and color indices published in the Third Reference Catalogue of Bright Galaxies (RC3, Cat. <VII/155>) are based on an analysis of ~26000 B, 25000 B-V, and 17000 U-B multiaperture measurements available up to mid 1987 from nearly 350 sources. This paper provides the full details of the analysis and estimates of internal and external errors in the parameters. The derivation of the parameters is based on techniques described by de Vaucouleurs & Corwin (1977ApJS...33..219D) whereby photoelectric multiaperture data are fitted by mean Hubble-type-dependent curves which describe the integral of the B-band flux and the typical B-V and U-B integrated color gradients. A sophisticated analysis of the residuals of these measurements from the curves was made to allow for the random and systematic errors that affect such data. The result is a homogeneous set of total magnitudes B^A^_T_, total colors (B-V)_T_ and (U-B)_T_, and effective colors (B-V)_e_ and (U-B)_e_ for more than 3000 bright galaxies in RC3.
2756. Photographic study of A2197 and A2199
ID:
ivo://CDS.VizieR/J/MNRAS/239/459
Title:
Photographic study of A2197 and A2199
Short Name:
J/MNRAS/239/459
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radii, b26 magnitudes, (b-r) colors, position angles, and ellipticities have been measured on the plates of Palomar 48-inch Schmidt telescope taken in May 1976, for 6925 galaxies in a 5-sq deg field enclosing the close pair of rich clusters A2197 and A2199.
2757. Photometric and redshift catalog of 581 galaxies
ID:
ivo://CDS.VizieR/J/MNRAS/325/1002
Title:
Photometric and redshift catalog of 581 galaxies
Short Name:
J/MNRAS/325/1002
Date:
21 Oct 2021
Publisher:
CDS
Description:
File table1 contains names, positions, b_jori_ magnitudes, magnitude errors, redshifts, redshift errors, [OII]3727 emission-line fluxes (where detected) and identification codes for 485 early-type galaxies displaying consistent data quality suitable for statistical analyses. File table2 contains names, positions, b_jori_ magnitudes, magnitude errors, redshifts and redshift errors for 96 early-type galaxies displaying inconsistent data quality, unsuitable for statistical analyses.
2758. Photometric Catalog of Northern Bright Galaxies
ID:
ivo://CDS.VizieR/VII/147
Title:
Photometric Catalog of Northern Bright Galaxies
Short Name:
VII/147
Date:
21 Oct 2021
Publisher:
CDS
Description:
Galaxies are the most massive, luminous astronomical objects bound by self gravity and comprise the major fraction of luminous mass in the universe. Recent investigations of galaxies often require statistical analysis of a large body of observational data. High degree of homogeneity of the data is the key point to the success of such investigations. This catalog presents homogeneous photometric parameters of 791 northern bright galaxies on the basis of modern photographic surface photometry. Sample galaxies are taken from the Revised Shapley-Ames Catalog of Bright Galaxies (Sandage and Tammann 1981) and most of them are members of the Local Super-cluster. Observations were made with the 105cm Schmidt telescope at the Kiso Observatory, Institute of Astronomy, University of Tokyo, in the photographic V band (Kodak IIa-D emulsion combined with a Schott GG 495 filter) mostly during 1984-1988. Sample galaxies photographed on a total of 280 Schmidt plates were scanned with the PDS 2020 GMS microdensitometer at the Kiso Observatory during April-August 1988. Data reduction for standard surface photometry was carried out using a software library SPIRAL (Ichikawa et al. 1987; Okamura 1988) during July-September 1988. The intensive plate measurement and data reduction secure high homogeneity of the present data. This catalog is the first machine-readable version (Ver.1) of Part II (The Catalog) of the 'Photometric Atlas of Northern Bright Galaxies' (Kodaira et al. 1990), which also includes in Part III illustrative information such as images, isophotal maps, luminosity profiles, and ellipses fitted to the isophotes. Image data of sample galaxies can be obtained in FITS format magnetic tapes upon request, and it is planned to distribute them on CD-ROMs. We request that those errors in this catalog that are found by the user be transmitted to S. Ichikawa, National Astronomical Observatory, Mitaka, Tokyo 181 Japan (e-mail : richika@c1.mtk.nao.ac.jp) so that they can be corrected in future versions.
2759. Photometric catalogs for ECDF-S and CDF-N
ID:
ivo://CDS.VizieR/J/ApJ/742/3
Title:
Photometric catalogs for ECDF-S and CDF-N
Short Name:
J/ApJ/742/3
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an analysis of deep multiwavelength data for z~0.3-3 starburst galaxies selected by their 70um emission in the Extended-Chandra Deep Field-South and Extended Groth Strip. We identify active galactic nuclei (AGNs) in these infrared sources through their X-ray emission and quantify the fraction that host an AGN. Lastly, we investigate the ratio between the supermassive black hole accretion rate (inferred from the AGN X-ray luminosity) and the bulge growth rate of the host galaxy (approximated as the SFR) and find that, for sources with detected AGNs and star formation (and neglecting systems with low star formation rates to which our data are insensitive), this ratio in distant starbursts agrees well with that expected from the local scaling relation assuming the black holes and bulges grew at the same epoch. These results imply that black holes and bulges grow together during periods of vigorous star formation and AGN activity.
2760. Photometric characterization of the CIG sample
ID:
ivo://CDS.VizieR/J/MNRAS/390/881
Title:
Photometric characterization of the CIG sample
Short Name:
J/MNRAS/390/881
Date:
21 Oct 2021
Publisher:
CDS
Description:
We perform a detailed photometric analysis (bulge-disc-bar decomposition and Concentration-Asymmetry-Clumpiness (CAS) parametrization) for a well-defined sample of isolated galaxies, extracted from the Catalog of Isolated Galaxies and reevaluated morphologically in the context of the Analysis of the interstellar Medium of Isolated GAlaxies project. We focus on Sb-Sc morphological types, as they are the most representative population among the isolated spiral galaxies. Our analysis yields a large number of important galactic parameters and various correlation plots are used to seek relationships that might shed light on the processes involved in determining those parameters. Assuming that the bulge Sersic index and/or bulge/total luminosity ratios are reasonable diagnostics for pseudo- versus classical bulges, we conclude that the majority of late-type isolated disc galaxies likely host pseudo-bulges rather than classical bulges.