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- ID:
- ivo://CDS.VizieR/J/ApJ/622/772
- Title:
- Redshift survey of submillimeter galaxies
- Short Name:
- J/ApJ/622/772
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have obtained spectroscopic redshifts using the Keck I telescope for a sample of 76 submillimeter galaxies (SMGs), with a median 850{mu}m flux density of 5.7mJy, for which precise positions are available through their faint radio emission.
3023. Red supergiants in M31
- ID:
- ivo://CDS.VizieR/J/ApJ/703/420
- Title:
- Red supergiants in M31
- Short Name:
- J/ApJ/703/420
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Red supergiants (RSGs) are a short-lived stage in the evolution of moderately massive stars (10-25M_{sun}_), and as such their location in the H-R diagram provides an exacting test of stellar evolutionary models. Since massive star evolution is strongly affected by the amount of mass loss a star suffers, and since the mass-loss rates depend upon metallicity, it is highly desirable to study the physical properties of these stars in galaxies of various metallicities. Here we identify a sample of RSGs in M31, the most metal-rich of the Local Group galaxies. We determine the physical properties of these stars using both moderate resolution spectroscopy and broadband V-K photometry. We find that on average the RSGs of our sample are variable in V by 0.5mag, smaller but comparable to the 0.9mag found for Magellanic Cloud (MC) RSGs. No such variability is seen at K, also in accord with what we know of Galactic and MC RSGs.
- ID:
- ivo://CDS.VizieR/J/AJ/161/79
- Title:
- Red supergiant stars in M31 and M33
- Short Name:
- J/AJ/161/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We identify red supergiants (RSGs) in our spiral neighbors M31 and M33 using near-IR (NIR) photometry complete to a luminosity limit of logL/L{odot}=4.0. Our archival survey data cover 5{deg}^2^ of M31, and 3{deg}^2^ for M33, and are likely spatially complete for these massive stars. Gaia is used to remove foreground stars, after which the RSGs can be separated from asymptotic giant branch (AGB) stars in the color-magnitude diagram. The photometry is used to derive effective temperatures and bolometric luminosities via MARCS stellar atmosphere models. The resulting H-R diagrams show superb agreement with the evolutionary tracks of the Geneva evolutionary group. Our census includes 6400 RSGs in M31 and 2850 RSGs in M33 within their Holmberg radii; by contrast, only a few hundred RSGs are known so far in the Milky Way. Our catalog serves as the basis for a study of the RSG binary frequency being published separately, as well as future studies relating to the evolution of massive stars. Here we use the matches between the NIR- selected RSGs and their optical counterparts to show that the apparent similarity in the reddening of OB stars in M31 and M33 is the result of Malmquist bias; the average extinction in M31 is likely higher than that of M33. As expected, the distribution of RSGs follows that of the spiral arms, while the much older AGB population is more uniformly spread across each galaxy's disk.
- ID:
- ivo://CDS.VizieR/J/A+A/551/A95
- Title:
- Reduced co-added LETGS spectrum of Ark 564
- Short Name:
- J/A+A/551/A95
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an analysis of the 100ks X-ray spectrum of the narrow-line Seyfert 1 Galaxy Ark 564, taken with the Low Energy Transmission Grating Spectrometer (LETGS) on board Chandra. Using chisquare statistics, several continuum models of the time-averaged spectrum of this object are compared, obtaining a semi-empirical solution for the description of the intrinsic emission continuum and a physical solution for the intrinsic absorption of the system. We find that the 0.1-10keV spectrum can be well described by a power law plus two thermal components that account for the soft step. We are also able to detect and measure several narrow, unresolved absorption lines arising from highly ionized species of C, N, O, and Fe. The material seems to have a velocity consistent with the systemic velocity of the galaxy. This piece of evidence, in addition to the very low observed column density of Nh~10^20^cm^-2^, is in good agreement with the scenario of a transverse biconical outflow with a gas density of n<3x10^12^cm^-3^ at distances beyond the broad-line region r>10lt-days, but a dust torus origin cannot be ruled out.
- ID:
- ivo://CDS.VizieR/VII/16
- Title:
- Reference Catalogue of Bright Galaxies
- Short Name:
- VII/16
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Reference Catalogue of Bright Galaxies lists for each entry the following information: NGC number, IC number, or A number; A, B, or C designation; B1950.0 positions, position at 100 year precession; galactic and supergalactic positions; revised morphological type and source; type and color class in Yerkes list 1 and 2; Hubble-Sandage type; revised Hubble type according to Holmberg; logarithm of mean major diameter (log D) and ratio of major to minor diameter (log R) and their weights; logarithm of major diameter; sources of the diameters; David Dunlap Observatory type and luminosity class; Harvard photographic apparent magnitude; weight of V, B-V(0), U-B(0); integrated magnitude B(0) and its weight in the B system; mean surface brightness in magnitude per square minute of arc and sources for the B magnitude; mean B surface brightness derived from corrected Harvard magnitude; the integrated color index in the standard B-V system; "intrinsic" color index; sources of B-V and/or U-B; integrated color in the standard U-B system; observed radial velocity in km/sec; radial velocity corrected for solar motion in km/sec; sources of radial velocities; solar motion correction; and direct photographic source. The catalog was created by concatenating four files side by side.
- ID:
- ivo://CDS.VizieR/J/A+A/499/357
- Title:
- REFLEX galaxies redshifts
- Short Name:
- J/A+A/499/357
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the final data from the spectroscopic survey of the ROSAT-ESO Flux-Limited X-ray (REFLEX) catalogue of galaxy clusters. The REFLEX survey covers 4.24 steradians (34% of the entire sky) below a declination +2.50{deg} and at high galactic latitude (|b|<20{deg}). The full survey includes 447 galaxy clusters with a median redshift of 0.08 and is better than 90% complete to a limiting flux of f_X_=3x10^-12^ergs/s/cm^2^ (3fW/m^2^, 0.1 to 2.4keV), representing the largest statistically homogeneous sample of clusters to date drawn from the ROSAT All-Sky Survey (RASS). Here we describe the details of the spectroscopic observations carried out at the ESO 1.5m, 2.2m and 3.6m telescopes, the data reduction and redshift measurements techniques. The spectra typically cover the wavelength range 3600-7500{AA} at a two-pixel resolution of ~14{AA} . From calibrations and external checks the redshifts are accurate to a typical rms error of +/-100km/s.
- ID:
- ivo://CDS.VizieR/J/ApJ/848/56
- Title:
- Relationships between SNe Ia and the host galaxies
- Short Name:
- J/ApJ/848/56
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a sample of 1338 spectroscopically confirmed and photometrically classified Type Ia supernovae (SNe Ia) sourced from Carnegie Supernova Project, Center for Astrophysics Supernova Survey, Sloan Digital Sky Survey-II, and SuperNova Legacy Survey SN samples to examine the relationships between SNe Ia and the galaxies that host them. Our results provide confirmation with improved statistical significance that SNe Ia, after standardization, are on average more luminous in massive hosts (significance >5{sigma}), and decline more rapidly in massive hosts (significance >9{sigma}) and in hosts with low specific star formation rates (significance >8{sigma}). We study the variation of these relationships with redshift and detect no evolution. We split SNe Ia into pairs of subsets that are based on the properties of the hosts and fit cosmological models to each subset. Including both systematic and statistical uncertainties, we do not find any significant shift in the best-fit cosmological parameters between the subsets. Among different SN Ia subsets, we find that SNe Ia in hosts with high specific star formation rates have the least intrinsic scatter ({sigma}_int_=0.08+/-0.01) in luminosity after standardization.
- ID:
- ivo://CDS.VizieR/J/ApJ/832/126
- Title:
- RESOLVE survey: 21cm obs. with GBT & Arecibo
- Short Name:
- J/ApJ/832/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the HI mass inventory for the REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey, a volume-limited, multi-wavelength census of >1500 z=0 galaxies spanning diverse environments and complete in baryonic mass down to dwarfs of ~10^9^M_{sun}_. This first 21cm data release provides robust detections or strong upper limits (1.4M_HI_<5%-10% of stellar mass M*) for ~94% of RESOLVE. We examine global atomic gas-to-stellar mass ratios (G/S) in relation to galaxy environment using several metrics: group dark matter halo mass M_h_, central/satellite designation, relative mass density of the cosmic web, and distance to the nearest massive group. We find that at fixed M*, satellites have decreasing G/S with increasing M_h_ starting clearly at M_h_~10^12^M_{sun}_, suggesting the presence of starvation and/or stripping mechanisms associated with halo gas heating in intermediate-mass groups. The analogous relationship for centrals is uncertain because halo abundance matching builds in relationships between central G/S, stellar mass, and halo mass, which depend on the integrated group property used as a proxy for halo mass (stellar or baryonic mass). On larger scales G/S trends are less sensitive to the abundance matching method. At fixed M_h_<=10^12^M_{sun}_, the fraction of gas-poor centrals increases with large-scale structure density. In overdense regions, we identify a rare population of gas-poor centrals in low-mass (M_h_<10^11.4^M_{sun}_) halos primarily located within ~1.5x the virial radius of more massive (M_h_>10^12^M_{sun}_) halos, suggesting that gas stripping and/or starvation may be induced by interactions with larger halos or the surrounding cosmic web. We find that the detailed relationship between G/S and environment varies when we examine different subvolumes of RESOLVE independently, which we suggest may be a signature of assembly bias.
- ID:
- ivo://CDS.VizieR/J/ApJ/810/166
- Title:
- RESOLVE survey photometry catalog
- Short Name:
- J/ApJ/810/166
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present custom-processed ultraviolet, optical, and near-infrared photometry for the REsolved Spectroscopy of a Local VolumE (RESOLVE) survey, a volume-limited census of stellar, gas, and dynamical mass within two subvolumes of the nearby universe (RESOLVE-A and RESOLVE-B). RESOLVE is complete down to baryonic mass ~10^9.1-9.3^M_{sun}_, probing the upper end of the dwarf galaxy regime. In contrast to standard pipeline photometry (e.g., SDSS), our photometry uses optimal background subtraction, avoids suppressing color gradients, and employs multiple flux extrapolation routines to estimate systematic errors. With these improvements, we measure brighter magnitudes, larger radii, bluer colors, and a real increase in scatter around the red sequence. Combining stellar mass estimates based on our optimized photometry with the nearly complete HI mass census for RESOLVE-A, we create new z=0 volume-limited calibrations of the photometric gas fractions (PGF) technique, which predicts gas-to-stellar mass ratios (G/S) from galaxy colors and optional additional parameters. We analyze G/S-color residuals versus potential third parameters, finding that axial ratio is the best independent and physically meaningful third parameter. We define a "modified color" from planar fits to G/S as a function of both color and axial ratio. In the complete galaxy population, upper limits on G/S bias linear and planar fits. We therefore model the entire PGF probability density field, enabling iterative statistical modeling of upper limits and prediction of full G/S probability distributions for individual galaxies. These distributions have two-component structure in the red color regime. Finally, we use the RESOLVE-B 21cm census to test several PGF calibrations, finding that most systematically under- or overestimate gas masses, but the full probability density method performs well.
