- ID:
- ivo://CDS.VizieR/J/MNRAS/404/1639
- Title:
- MILES base models & new line index system
- Short Name:
- J/MNRAS/404/1639
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present synthetic spectral energy distributions (SEDs) for single-age, single-metallicity stellar populations (SSPs) covering the full optical spectral range at moderately high resolution [full width at half-maximum (FWHM)=2.3{AA}]. These SEDs constitute our base models, as they combine scaled-solar isochrones with an empirical stellar spectral library [Medium resolution INT Library of Empirical Spectra (MILES)], which follows the chemical evolution pattern of the solar neighbourhood. The models rely as much as possible on empirical ingredients, not just on the stellar spectra, but also on extensive photometric libraries, which are used to determine the transformations from the theoretical parameters of the isochrones to observational quantities. The unprecedented stellar parameter coverage of the MILES stellar library allowed us to safely extend our optical SSP SED predictions from intermediate- to very-old-age regimes and the metallicity coverage of the SSPs from super-solar to [M/H]=-2.3. SSPs with such low metallicities are particularly useful for globular cluster studies. We have computed SSP SEDs for a suite of initial mass function shapes and slopes. We provide a quantitative analysis of the dependence of the synthesized SSP SEDs on the (in)complete coverage of the stellar parameter space in the input library that not only shows that our models are of higher quality than those of other works, but also in which range of SSP parameters our models are reliable.
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- ID:
- ivo://CDS.VizieR/J/ApJ/885/87
- Title:
- Milky Way mass model and rotation curve
- Short Name:
- J/ApJ/885/87
- Date:
- 15 Mar 2022 08:00:47
- Publisher:
- CDS
- Description:
- We discuss a model for the Milky Way obtained by fitting the observed terminal velocities with the radial acceleration relation. The resulting stellar surface density profile departs from a smooth exponential disk, having bumps and wiggles that correspond to massive spiral arms. These features are used to estimate the term for the logarithmic density gradient in the Jeans equation, which turn out to have exactly the right location and amplitude to reconcile the apparent discrepancy between the stellar rotation curve and that of the interstellar gas. This model also predicts a gradually declining rotation curve outside the solar circle with slope -1.7km/s/kpc, as subsequently observed.
- ID:
- ivo://CDS.VizieR/VII/240
- Title:
- Millennium Galaxy Catalogue
- Short Name:
- VII/240
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Millennium Galaxy Catalogue (MGC) is a 37.5deg^2^, medium-deep, B-band imaging survey along the celestial equator, taken with the Wide Field Camera on the Isaac Newton Telescope. The survey region is contained within the regions of both the Two Degree Field Galaxy Redshift Survey (2dFGRS) and the Sloan Digital Sky Survey Early Data Release (SDSS-EDR). The survey has a uniform isophotal detection limit of 26mag.arcsec^-2^ and it provides a robust, well-defined catalogue of stars and galaxies in the range 16<=B_MGC_<24 mag. Here we describe the survey strategy, the photometric and astrometric calibration, source detection and analysis, and present the galaxy number counts that connect the bright and faint galaxy populations within a single survey. We argue that these counts represent the state of the art and use them to constrain the normalizations ({phi}*) of a number of recent estimates of the local galaxy luminosity function. We find that the 2dFGRS, SDSS Commissioning Data (CD), ESO Slice Project, Century Survey, Durham/UKST, Mt Stromlo/APM, SSRS2 and NOG luminosity functions require a revision of their published {phi}* values by factors of 1.05+/-0.05, 0.76+/-0.10, 1.02+/-0.22, 1.02+/-0.16, 1.16+/-0.28, 1.75+/-0.37, 1.40+/-0.26 and 1.01+/-0.39, respectively. After renormalizing the galaxy luminosity functions we find a mean local b_J_ luminosity density of 1.986+/-0.031x10^8^h L_{sun}_.Mpc^-3^
- ID:
- ivo://CDS.VizieR/J/A+AS/102/611
- Title:
- Millimeter continuum of extragal. sources III.
- Short Name:
- J/A+AS/102/611
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/VII/200
- Title:
- Minislice at the North Galactic Pole. II.
- Short Name:
- VII/200
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalogue of 328 positions, redshifts, bJ magnitudes and bJ-rF colours of galaxies down to bJ=20.5 in 4x0.67 degrees slice close to the North Galactic Pole is presented. Two additional tables containing positions, magnitudes, colours and radial velocities for stars and galaxies not in the main catalogue are also included. The photometry errors are about 0.2 for magnitudes and 0.3 for the colours. The radial velocity errors are estimated as being about 70 km/s. The redshift completeness level of the sample is of the order of ~35% at bj=20.
- ID:
- ivo://CDS.VizieR/J/A+A/416/507
- Title:
- Minor-axis velocity gradients in disk galaxies
- Short Name:
- J/A+A/416/507
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the ionized-gas kinematics and photometry of a sample of 4 spiral galaxies which are characterized by a zero-velocity plateau along the major axis and a velocity gradient along the minor axis, respectively. By combining these new kinematical data with those available in the literature for the ionized-gas component of the S0s and spirals listed in the Revised Shapley-Ames Catalog of Bright Galaxies we realized that about 50% of unbarred galaxies show a remarkable gas velocity gradient along the optical minor axis. This fraction rises to about 60% if we include unbarred galaxies with an irregular velocity profile along the minor axis. This phenomenon is observed all along the Hubble sequence of disk galaxies, and it is particularly frequent in early-type spirals. Since minor-axis velocity gradients are unexpected if the gas is moving onto circular orbits in a disk coplanar to the stellar one, we conclude that non-circular and off-plane gas motions are not rare in the inner regions of disk galaxies.
- ID:
- ivo://CDS.VizieR/J/MNRAS/423/197
- Title:
- MIPS photometry for Herschel SAG2 Programs
- Short Name:
- J/MNRAS/423/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide an overview of ancillary 24, 70, and 160 micron data from the Multiband Imaging Photometer for Spitzer (MIPS) that are intended to complement the 70-500 micron Herschel Space Observatory photometry data for nearby galaxies obtained by the Herschel-SPIRE Local Galaxies Guaranteed Time Programs and the Herschel Virgo Cluster Survey. The MIPS data can be used to extend the photometry to wave bands that are not observed in these Herschel surveys and to check the photometry in cases where Herschel performs observations at the same wavelengths. Additionally, we measured globally-integrated 24-160 micron flux densities for the galaxies in the sample that can be used for the construction of spectral energy distributions. Using MIPS photometry published by other references, we have confirmed that we are obtaining accurate photometry for these galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/191/212
- Title:
- MIPS sources near the South Ecliptic Pole
- Short Name:
- J/ApJS/191/212
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have imaged an 11.5deg^2^ region of sky toward the South Ecliptic Pole (SEP; J0443-5340) at 24 and 70um with MIPS, the Multiband Imaging Photometer for Spitzer. This region is coincident with a field mapped at longer wavelengths by AKARI and BLAST. We discuss our data reduction and source extraction procedures. The median 1{sigma} depths of the maps are 47uJy/beam at 24um and 4.3mJy/beam at 70um. At 24um, we identify 93098 point sources with signal-to-noise ratio (S/N)>=5 and an additional 63 resolved galaxies; at 70um we identify 891 point sources with S/N>=6. From simulations, we determine a false detection rate of 1.8% (1.1%) for the 24um (70um) catalog. The 24 and 70um point-source catalogs are 80% complete at 230uJy and 11mJy, respectively.
- ID:
- ivo://CDS.VizieR/J/ApJ/723/1110
- Title:
- MIPS 24um observations of the HDFS
- Short Name:
- J/ApJ/723/1110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present MIPS 24um observations of the Hubble Deep Field South taken with the Spitzer Space Telescope. The resulting image is 254arcmin^2^ in size and has a sensitivity ranging between ~12 and ~30uJy rms, with a median sensitivity of ~20uJy rms. A total of 495 sources have been catalogued with a signal-to-noise ratio greater than 5{sigma}. The source catalog is presented as well as source counts which have been corrected for completeness and flux boosting. The IR sources are then combined with MUSYC optical/NIR and ATHDFS radio observations to obtain redshifts and radio flux densities of the sample. We use the IR/radio flux density ratio (q_24_) to explore the IR-radio correlation for this IR sample and find q_24_=0.71+/-0.31 for sources detected in both IR and radio. The results are extended by stacking IR sources not detected in the radio observations and we derive an average q_24_ for redshift bins between 0<z<2.5. We find that the high-redshift (z>1) sources have an average q_24_ ratio which is better fit by local LIRG SEDs rather than local ULIRG SEDs, indicating that high-redshift ULIRGs differ in their IR/radio properties. So, ULIRGs at high-redshift have SEDs different from those found locally. Infrared-faint radio sources are examined, and while nine radio sources do not have an MIPS detection and are therefore radio-loud active galactic nuclei (AGNs), only one radio source has an extreme IRAC 3.6um to radio flux density ratio indicating it is a radio-loud AGN at z>1.
- ID:
- ivo://CDS.VizieR/J/MNRAS/459/1403
- Title:
- M31 IRAC 3.6/4.5um extended survey
- Short Name:
- J/MNRAS/459/1403
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the first results from an extended survey of the Andromeda galaxy (M31) using 41.1h of observations by Spitzer-IRAC at 3.6 and 4.5{mu}m. This survey extends previous observations to the outer disc and halo, covering total lengths of 44 and 66 along the minor and major axes, respectively. We have produced surface brightness profiles by combining the integrated light from background-corrected maps with stellar counts from a new catalogue of point sources. Using auxiliary catalogues, we have carried out a statistical analysis in colour-magnitude space to discriminate M31 objects from foreground Milky Way stars and background galaxies. The catalogue includes 426 529 sources, of which 66 per cent have been assigned probability values to identify M31 objects with magnitude depths of [3.6]=19.0+/-0.2, [4.5]=18.7+/-0.2. We discuss applications of our data for constraining the stellar mass and characterizing point sources in the outer radii.