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5742. RZ Dra BVR light curves
- ID:
- ivo://CDS.VizieR/J/AJ/140/1687
- Title:
- RZ Dra BVR light curves
- Short Name:
- J/AJ/140/1687
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new multicolor photometry for RZ Draconis, observed in 2009 at the Xinglong Station of the National Astronomical Observatories of China. By using the updated version of the Wilson-Devinney Code, the photometric-spectroscopic elements were deduced from new photometric observations and published radial velocity data.
- ID:
- ivo://CDS.VizieR/J/A+A/513/A38
- Title:
- RZJHK photometry for stellar sources in Serpens
- Short Name:
- J/A+A/513/A38
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a deep optical/near-infrared imaging survey of the Serpens molecular cloud. This survey constitutes the complementary optical data to the Spitzer "Core To Disk" (c2d) Legacy survey in this cloud. The survey was conducted using the Wide Field Camera at the Isaac Newton Telescope. About 0.96 square degrees were imaged in the R and Z filters, covering the entire region where most of the young stellar objects identified by the c2d survey are located. 26524 point-like sources were detected in both R and Z bands down to R=24.5mag and Z=23mag with a signal-to-noise ratio better than 3. The 95% completeness limit of our catalog corresponds to 0.04 solar masses for members of the Serpens star forming region (age 2Myr and distance 260pc) in the absence of extinction. Adopting the typical extinction of the observed area (Av=7mag), we estimate a 95% completeness level down to 0.1 solar masses. The astrometric accuracy of our catalog is 0.4-arcsec with respect to the 2MASS catalog. Our final catalog contains J2000 celestial coordinates, magnitudes in the R and Z bands calibrated to the SDSS photometric system and, where possible, JHK magnitudes from 2MASS for sources in 0.96 square degrees in the direction of Serpens. This data product has been already used within the frame of the c2d Spitzer Legacy Project analysis in Serpens to study the star/disk formation and evolution in this cloud; here we use it to obtain new indications of the disk-less population in Serpens.
5744. RZ Tau UBVR photometry
- ID:
- ivo://CDS.VizieR/J/A+A/343/894
- Title:
- RZ Tau UBVR photometry
- Short Name:
- J/A+A/343/894
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/ApJ/787/110
- Title:
- SAGA: Stromgren survey of seismic KIC stars
- Short Name:
- J/ApJ/787/110
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Asteroseismology has the capability of precisely determining stellar properties that would otherwise be inaccessible, such as radii, masses, and thus ages of stars. When coupling this information with classical determinations of stellar parameters, such as metallicities, effective temperatures, and angular diameters, powerful new diagnostics for Galactic studies can be obtained. The ongoing Stromgren survey for Asteroseismology and Galactic Archaeology (SAGA) has the goal of transforming the Kepler field into a new benchmark for Galactic studies, similar to the solar neighborhood. Here we present the first results from a stripe centered at a Galactic longitude of 74{deg} and covering latitude from about 8{deg} to 20{deg}, which includes almost 1000 K giants with seismic information and the benchmark open cluster NGC 6819. We describe the coupling of classical and seismic parameters, the accuracy as well as the caveats of the derived effective temperatures, metallicities, distances, surface gravities, masses, and radii. Confidence in the achieved precision is corroborated by the detection of the first and secondary clumps in a population of field stars with a ratio of 2 to 1 and by the negligible scatter in the seismic distances among NGC 6819 member stars. An assessment of the reliability of stellar parameters in the Kepler Input Catalog is also performed, and the impact of our results for population studies in the Milky Way is discussed, along with the importance of an all-sky Stromgren survey.
- ID:
- ivo://CDS.VizieR/J/A+A/572/A42
- Title:
- SagDIG carbon and oxygen stars
- Short Name:
- J/A+A/572/A42
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Sagittarius dwarf irregular (also known as SagDIG or UKS 1927-177) is a gas-rich, low-metallicity and star-forming galaxy, at the outskirts (D~1.1Mpc) of the Local Group. Projected relatively close to the Galactic center [(l,b)=(21.06,-16.29)] the resolved stellar populations of this galaxy reflects a strong Galactic foreground contamination, attributed to the thin and thick disk and the halo. This has so far hampered the reconstruction of its star formation and chemical enrichment history, and studies of individual stars. We have analyzed two ACS@HST data-sets (GO-9820 and GO-10472) that were collected in August 2003 and June 2005, having a ~1.85 years epoch separation. The data has allowed the derivation of the relative proper-motion for the SagDIG stellar population and reduction of the heavy foreground contamination. This provides a much clearer view of the red stellar populations (young RSG and intermediate-age AGB as well as the old RGB and AGB). The ACS/WFC data was collected in the F475W, F606W and F814W HST filters, and the published table provides a photometric calibration of the ACS/WFC filters that follows Bedin et al. (2003AJ....126..247B). This is based on the Vega spectrum and follows the recipes given by Holtzmann et al. (1995PASP..107..156H) for WFPC2, using the most updated in-flight characterization of the camera (Sirianni et al. 2005PASP..117.1049S). Besides the reported magnitudes and their relative errors, we also provide the pixel-based offset between the two F814W epochs, which is used to separate the SagDIG stellar population from the Galactic foreground (see Sec.3 of the paper for details).
5747. SAGE AGB candidates
- ID:
- ivo://CDS.VizieR/J/ApJ/723/1195
- Title:
- SAGE AGB candidates
- Short Name:
- J/ApJ/723/1195
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We combine variability information from the MAssive Compact Halo Objects survey of the Large Magellanic Cloud with infrared photometry from the Spitzer Space Telescope Surveying the Agents of a Galaxy's Evolution survey to create a data set of ~30000 variable red sources. We photometrically classify these sources as being on the first ascent of the red giant branch, or as being in one of three stages along the asymptotic giant branch (AGB): oxygen-rich, carbon-rich, or highly reddened with indeterminate chemistry ("extreme" AGB candidates). We present linear period-luminosity (P-L) relationships for these sources using eight separate infrared bands (J, H, Ks, 3.6, 4.5, 5.8, 8.0, and 24um) as proxies for the luminosity. We find that the wavelength dependence of the slope of the P-L relationship is different for different photometrically determined classes of AGB stars. Stars photometrically classified as O-rich show the least variation of slope with wavelength, while dust enshrouded extreme AGB stars show a pronounced trend toward steeper slopes with increasing wavelength. We find that O-rich AGB stars pulsating in the fundamental mode obey a period-magnitude relation with a slope of -3.41+/-0.04 when magnitude is measured in the 3.6um band, in contrast to C-rich AGB stars, which obey a relation of slope -3.77+/-0.05.
5748. SAGE calibration stars
- ID:
- ivo://CDS.VizieR/J/AJ/132/2268
- Title:
- SAGE calibration stars
- Short Name:
- J/AJ/132/2268
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We are performing a uniform and unbiased imaging survey of the Large Magellanic Cloud (LMC; ~7{deg}x7{deg}) using the IRAC (3.6, 4.5, 5.8, and 8um) and MIPS (24, 70, and 160um) instruments on board the Spitzer Space Telescope in the Surveying the Agents of a Galaxy's Evolution (SAGE) survey, these agents being the interstellar medium (ISM) and stars in the LMC. This paper provides an overview of the SAGE Legacy project, including observing strategy, data processing, and initial results. The observing strategy includes two epochs in 2005, separated by 3 months, that both mitigate instrumental artifacts and constrain source variability. The SAGE data are nonproprietary. The data processing includes IRAC and MIPS pipelines and a database for mining the point-source catalogs, which will be released to the community in support of Spitzer proposal cycles 4 and 5. We present initial results on the epoch 1 data for a region near N79 and N83. The MIPS 70 and 160um images of the diffuse dust emission of the N79/N83 region reveal a similar distribution to the gas emissions, especially the HI 21cm emission.
- ID:
- ivo://CDS.VizieR/II/305
- Title:
- SAGE LMC and SMC IRAC Source Catalog
- Short Name:
- II/305
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The SAGE project is a Cycle 2 legacy program on the Spitzer Space Telescope, entitled, "Spitzer Survey of the Large Magellanic Cloud: Surveying the Agents of a Galaxy's Evolution (SAGE)", with Margaret Meixner (STScI) as the PI. The project overview and initial results are described in a paper by Meixner et al. (2006AJ....132.2268M). The Catalog is a highly reliable list of 6.4 million sources. Faint limits for SAGE are 18.1, 17.5, 15.3, and 14.2 for IRAC 3.6, 4.5, 5.8, 8.0 um, respectively. The SAGE-SMC project is a Cycle 4 legacy program on the Spitzer Space Telescope, entitled, "SAGE-SMC: Surveying the Agents of Galaxy Evolution in the Tidally-Disrupted, Low-Metallicity Small Magellanic Cloud", with Karl Gordon (STScI) as the PI. The project overview and initial results are described in a paper by Gordon et al. (2011AJ....142..102G). The Catalog is a highly reliable list of 2.0 million sources. Faint limits for SAGE-SMC are 18.3, 17.7, 15.7, and 14.5 for IRAC 3.6, 4.5, 5.8, 8.0 um, respectively. The archive tables are more complete but less reliable than the catalogs. IRAC Single Frame + Mosaic Photometry Catalog: a combination of mosaic photometry source list extracted from the combined Epoch 1 and Epoch 2 12 second frametime mosaics with all-epochs single frame source list, bandmerged with 2MASS or 2MASS6X. Detailed documentations are available from http://irsa.ipac.caltech.edu/data/SPITZER/SAGE/doc/ as SAGEDataProductsDescription_Sep09.pdf and from http://irsa.ipac.caltech.edu/data/SPITZER/SAGE-SMC/docs/ as sage-smc_delivery_apr11.pdf
- ID:
- ivo://CDS.VizieR/J/MNRAS/470/3250
- Title:
- SAGE LMC point-sources classification
- Short Name:
- J/MNRAS/470/3250
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Infrared Spectrograph (IRS) on the Spitzer Space Telescope observed nearly 800 point sources in the Large Magellanic Cloud (LMC), taking over 1000 spectra. 197 of these targets were observed as part of the SAGE-Spec Spitzer Legacy program; the remainder are from a variety of different calibration, guaranteed time and open time projects. We classify these point sources into types according to their infrared spectral features, continuum and spectral energy distribution shape, bolometric luminosity, cluster membership and variability information, using a decision-tree classification method. We then refine the classification using supplementary information from the astrophysical literature. We find that our IRS sample is comprised substantially of YSO and HII regions, post-main-sequence low-mass stars: (post-)asymptotic giant branch stars and planetary nebulae and massive stars including several rare evolutionary types. Two supernova remnants, a nova and several background galaxies were also observed. We use these classifications to improve our understanding of the stellar populations in the LMC, study the composition and characteristics of dust species in a variety of LMC objects, and to verify the photometric classification methods used by mid-IR surveys. We discover that some widely used catalogues of objects contain considerable contamination and others are missing sources in our sample.
